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CHEMISTRY (537 journals)            First | 1 2 3 4 5 6 | Last

Journal of Fuel Chemistry and Technology     Full-text available via subscription   (Followers: 5)
Journal of Great Lakes Research     Hybrid Journal   (Followers: 7)
Journal of Heterocyclic Chemistry     Hybrid Journal   (Followers: 5)
Journal of Immunoassay and Immunochemistry     Hybrid Journal   (Followers: 3)
Journal of Inclusion Phenomena and Macrocyclic Chemistry     Hybrid Journal   (Followers: 2)
Journal of Inorganic Biochemistry     Hybrid Journal   (Followers: 2)
Journal of Labelled Compounds and Radiopharmaceuticals     Hybrid Journal   (Followers: 1)
Journal of Macromolecular Science, Part A: Pure and Applied Chemistry     Hybrid Journal   (Followers: 4)
Journal of Mass Spectrometry     Hybrid Journal   (Followers: 20)
Journal of Materials Chemistry A : Materials for Energy and Sustainability     Full-text available via subscription   (Followers: 23)
Journal of Materials Chemistry B : Materials for Biology and Medicine     Full-text available via subscription   (Followers: 5)
Journal of Materials Chemistry C : Materials for Optical, Magnetic and Electronic Devices     Full-text available via subscription   (Followers: 6)
Journal of Materials Research     Full-text available via subscription   (Followers: 9)
Journal of Mathematical Chemistry     Hybrid Journal   (Followers: 4)
Journal of Medicinal Chemistry     Full-text available via subscription   (Followers: 179)
Journal of Membrane Science     Hybrid Journal   (Followers: 10)
Journal of Modern Chemistry & Chemical Technology     Full-text available via subscription   (Followers: 2)
Journal of Molecular Catalysis A: Chemical     Hybrid Journal   (Followers: 2)
Journal of Molecular Graphics and Modelling     Hybrid Journal   (Followers: 4)
Journal of Molecular Liquids     Hybrid Journal   (Followers: 3)
Journal of Molecular Modeling     Hybrid Journal   (Followers: 3)
Journal of Molecular Recognition     Hybrid Journal   (Followers: 1)
Journal of Molecular Spectroscopy     Hybrid Journal   (Followers: 6)
Journal of Molecular Structure     Hybrid Journal   (Followers: 3)
Journal of Nanoparticles     Open Access  
Journal of Nanostructure in Chemistry     Open Access   (Followers: 5)
Journal of Natural Gas Chemistry     Full-text available via subscription   (Followers: 2)
Journal of Nepal Chemical Society     Open Access  
Journal of Nucleic Acids Investigation     Open Access   (Followers: 2)
Journal of Ocean University of China (English Edition)     Hybrid Journal   (Followers: 2)
Journal of Organometallic Chemistry     Hybrid Journal   (Followers: 12)
Journal of Photochemistry and Photobiology A: Chemistry     Hybrid Journal   (Followers: 4)
Journal of Photochemistry and Photobiology C: Photochemistry Reviews     Full-text available via subscription   (Followers: 4)
Journal of Polymer Science Part A: Polymer Chemistry     Hybrid Journal   (Followers: 172)
Journal of Polymers     Open Access   (Followers: 1)
Journal of Porphyrins and Phthalocyanines     Hybrid Journal   (Followers: 2)
Journal of Pure and Applied Chemistry Research     Open Access   (Followers: 1)
Journal of Raman Spectroscopy     Hybrid Journal   (Followers: 10)
Journal of Saudi Chemical Society     Open Access  
Journal of Solid State Chemistry     Hybrid Journal   (Followers: 13)
Journal of Solution Chemistry     Hybrid Journal  
Journal of Structural Chemistry     Hybrid Journal  
Journal of Sulfur Chemistry     Hybrid Journal   (Followers: 2)
Journal of Superhard Materials     Hybrid Journal   (Followers: 1)
Journal of Surfactants and Detergents     Hybrid Journal   (Followers: 5)
Journal of Systems Chemistry     Open Access   (Followers: 1)
Journal of Taibah University for Science     Open Access  
Journal of the American Chemical Society     Full-text available via subscription   (Followers: 262)
Journal of the American Society for Mass Spectrometry     Hybrid Journal   (Followers: 17)
Journal of the American Society of Brewing Chemists     Full-text available via subscription   (Followers: 1)
Journal of the Bangladesh Chemical Society     Open Access  
Journal of the Chilean Chemical Society     Open Access   (Followers: 2)
Journal of the Iranian Chemical Society     Hybrid Journal   (Followers: 1)
Journal of the Korean Society for Applied Biological Chemistry     Hybrid Journal   (Followers: 1)
Journal of the Mexican Chemical Society     Open Access   (Followers: 1)
Journal of Theoretical and Computational Chemistry     Hybrid Journal   (Followers: 7)
Journal of Theoretical Chemistry     Open Access  
Journal of Wood Chemistry and Technology     Hybrid Journal   (Followers: 7)
JPC - Journal of Planar Chromatography - Modern TLC     Full-text available via subscription   (Followers: 6)
Jurnal Penelitian Sains (JPS)     Open Access  
Jurnal Teknologi Informasi     Open Access   (Followers: 3)
Kinetics and Catalysis     Hybrid Journal   (Followers: 3)
Korea-Australia Rheology Journal     Hybrid Journal  
Langmuir     Full-text available via subscription   (Followers: 35)
Latvian Journal of Chemistry     Open Access   (Followers: 1)
Lebensmittelchemie     Hybrid Journal   (Followers: 1)
Lipid Insights     Open Access   (Followers: 1)
Luminescence     Hybrid Journal   (Followers: 1)
Macromolecular Materials & Engineering     Hybrid Journal   (Followers: 4)
Macromolecular Rapid Communications     Hybrid Journal   (Followers: 4)
Macromolecular Research     Hybrid Journal  
Macromolecular Symposia     Hybrid Journal  
Macromolecular Theory and Simulations     Hybrid Journal  
Macromolecules     Full-text available via subscription   (Followers: 31)
Magnetic Resonance in Chemistry     Hybrid Journal   (Followers: 4)
Main Group Chemistry     Hybrid Journal  
Marine Chemistry     Hybrid Journal   (Followers: 4)
Marine Drugs     Open Access   (Followers: 4)
MATEC Web of Conferences     Open Access  
Materials Characterization     Hybrid Journal   (Followers: 21)
Materials Horizons     Full-text available via subscription  
Materials Research Bulletin     Hybrid Journal   (Followers: 16)
Materials Science Monographs     Full-text available via subscription   (Followers: 1)
Materials Science-Poland     Hybrid Journal  
Materials Sciences and Applications     Open Access   (Followers: 4)
MedChemComm     Full-text available via subscription   (Followers: 4)
Medicinal Chemistry Research     Hybrid Journal   (Followers: 10)
Metallography, Microstructure, and Analysis     Hybrid Journal   (Followers: 1)
Metallomics     Full-text available via subscription  
Micro and Nano Systems Letters     Open Access   (Followers: 1)
Microchimica Acta     Hybrid Journal   (Followers: 2)
Microporous and Mesoporous Materials     Hybrid Journal   (Followers: 3)
Modern Research in Catalysis     Open Access   (Followers: 2)
Molbank     Open Access  
Molecules     Open Access   (Followers: 3)
Molecules and Cells     Hybrid Journal   (Followers: 1)
Monatshefte für Chemie - Chemical Monthly     Hybrid Journal   (Followers: 3)
Mongolian Journal of Chemistry     Open Access  
Moroccan Journal of Chemistry     Open Access  
Moscow University Chemistry Bulletin     Hybrid Journal   (Followers: 2)

  First | 1 2 3 4 5 6 | Last

Journal Cover Photochemistry and Photobiology
   Journal TOC RSS feeds Export to Zotero [3 followers]  Follow    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
     ISSN (Print) 0031-8655 - ISSN (Online) 1751-1097
     Published by John Wiley and Sons Homepage  [1604 journals]   [SJR: 0.709]   [H-I: 86]
  • Analysis of Oxyluciferin Photoluminescence Pathways in Aqueous Solutions
    • Authors: Miyabi Hiyama; Toshimitsu Mochizuki, Hidefumi Akiyama, Nobuaki Koga
      Pages: n/a - n/a
      Abstract: We evaluated the pKa values of oxyluciferin and its conjugate acids and bases theoretically with the help of experimental correction values, from which free energies for the first excited and the ground states of all the species were estimated. On the basis of these results, we calculated pH‐dependent absorption spectra, where the relative absorption intensities of various species strongly depend on photo‐excitation energy, and we further analysed the photoluminescence pathways of oxyluciferin in aqueous solutions with various pH. In the case of 350 nm photo‐excitation, in particular, experiments have shown that dominant emission colour is green and it attenuates with pH decreasing, while blue (3 < pH < 8) and red (pH < 3) emissions appear. Our present results clarify the pathways of these photoluminescence depending on the pH values and thus should be useful in further analyses of photoluminescence pathways for other photo‐excitation wavelength in comparison with experiments. This article is protected by copyright. All rights reserved.
      PubDate: 2014-10-21T07:52:11.713827-05:
      DOI: 10.1111/php.12370
  • Combination of Er:YAG Laser and CO2 Laser treatment on skin tissue
    • Authors: Sana Mohammeb Anayb Baleg; Noriah Bidin, Lau Pik Suan, Muhammad Fakarruddin Sidi Ahmad, Ganesan Krishnan, Asmah Hamid
      Pages: n/a - n/a
      Abstract: The skin is the most important organ in our body, as it protects us from external environmental effects. The study of the ability of the skin to stretch and the histological examinations of irradiated tissues have significant values in scientific and medical applications. Only a few studies have been done to study the correlation between epidermis ablation and the changes that occur at dermal levels when using dual lasers in ablative resurfacing mode. The aim of this work is to determine this correlation and to estimate the effects of multiple pulses on induced collagen remodelling and the strength of skin exposed with dual lasers in an in vivo rat model. All laser exposures led to marked improvements in the skin's strength compared to their own controls. The histological investigation indicated that there was a thickness loss in the epidermis layer with the induction of deep collagen coagulation in the dermis layer as the dual laser pulses increased. Additionally, more collagen fibres were remoulded in the treated samples by dual wavelengths. We conclude that by combining dual lasers with multiple pulses targeted at not only the epidermis layer of the skin, it could also induce some heat diffusion in the dermis layer which causes more coagulation of collagen fibres. The tensile results confirmed by our histological data demonstrates that the strength of irradiated skin with dual wavelengths increased more than using both lasers separately on the skin tissue since more collagen is induced. This article is protected by copyright. All rights reserved.
      PubDate: 2014-10-18T05:22:00.861954-05:
      DOI: 10.1111/php.12369
  • Oxidatively generated damage to cellular DNA by UVB and UVA radiation
    • Authors: Jean Cadet; Thierry Douki, Jean‐Luc Ravanat
      Pages: n/a - n/a
      Abstract: This review article focuses on a critical survey of the main available information on the UVB and UVA oxidative reactions to cellular DNA as the result of direct interactions of UV photons, photosensitized pathways and biochemical responses including inflammation and bystander effect. UVA radiation appears to be much more efficient than UVB in inducing oxidatively generated damage to the bases and 2‐deoxyribose moieties of DNA in isolated cells and skin. The UVA‐induced generation of 8‐oxo‐7,8‐dihydroguanine is mostly rationalized in terms of selective guanine oxidation by singlet oxygen generated through type II photosensitization mechanism. In addition, hydroxyl radical whose formation may be accounted for by metal‐catalyzed Haber‐Weiss reactions subsequent to the initial generation of superoxide anion radical contributes in a minor way to the DNA degradation. This leads to the formation of both oxidized purine and pyrimidine bases together with DNA single strand breaks at the exclusion however of direct double strand breaks. No evidence has been provided so far for the implication of delayed oxidative degradation pathways of cellular DNA. In that respect putative characteristic UVA‐induced DNA damage could include single and more complex lesions arising from one‐electron oxidation of the guanine base together with aldehyde adducts to amino‐substituted nucleobases. This article is protected by copyright. All rights reserved.
      PubDate: 2014-10-18T05:21:59.199749-05:
      DOI: 10.1111/php.12368
  • Photoisomerization of
           cis‐1,2‐di(1‐Methyl‐2‐naphthyl)ethene at 77
           K in Glassy Media
    • Authors: Christopher Redwood; V. K. Ratheesh Kumar, Stuart Hutchinson, Frank B. Mallory, Clelia W. Mallory, Ronald J. Clark, Olga Dmitrenko, Jack Saltiel
      Pages: n/a - n/a
      Abstract: cis‐1,2‐Di(1‐methyl‐2‐naphthyl)ethene, c‐1,1, undergoes photoisomerization in methylcyclohexane, isopentane and diethyl ether/isopentane/ethanol glasses at 77 K. On 313 nm excitation the fluorescence of c‐1,1 is replaced by fluorescence from t‐1,1. Singular value decomposition reveals that the spectral matrices behave as two component systems suggesting conversion of a stable c‐1,1 conformer to a stable t‐1,1 conformer. However, the fluorescence spectra are λexc dependent. Analysis of global spectral matrices shows that c‐1,1 is a mixture of two conformers each of which gives one of four known t‐1,1 conformers. The λexc dependence of the c‐1,1 fluorescence spectrum is barely discernible. Structure assignments to the resolved fluorescence spectra are based on the principle of least motion and on calculated geometries, energy differences and spectra of the conformers. The relative shift of the c‐1,1 conformer spectra is consistent with the shift of the calculated absorption spectra. The calculated structure of the most stable conformer of c‐1,1 agrees well with the X‐ray crystal structure. Due to large deviations of the naphthyl groups from the ethenic plane in the conformers of both c‐ and t‐1,1 isomers, minimal motion of these bulky substituents accomplishes cis → trans interconversion by rotation about the central bond. This article is protected by copyright. All rights reserved.
      PubDate: 2014-10-18T05:21:57.559828-05:
      DOI: 10.1111/php.12367
  • N4‐Methylation of cytosine drastically favors the formation of
           (6–4) photoproducts in a TCG context
    • Authors: Thierry Douki; Jarah A. Meador, Izabel Bérard, Aude Wack
      Pages: n/a - n/a
      Abstract: Methylation of cytosine is a common biological process both in prokaryotic and eukaryotic cells. In addition to 5–methylcytosine (5mC), some bacterial species contain in their genome N4–methylcytosine (N4mC). Methylation at C5 has been shown to enhance the formation of pyrimidine dimeric photoproducts but nothing is known of the effect of N4 methylation on UV‐induced DNA damage. In the present work, we compared the yield and the nature of bipyrimidine photoproducts induced in a series of trinucleotides exhibiting a TXG sequence where X is either T, C, 5mC or N4mC. HPLC associated to tandem mass spectrometry was used to quantify cyclobutane pyrimidine dimers (CPD), (6‐4) photoproducts (64PP) and their Dewar valence isomer. Methylation at position N4 was found to drastically increase the reactivity of C upon exposure to both UVC and UVB and to favor the formation of 64PP. In contrast methylation at C5 increased the yield of CPD at the expense of 64PP. In addition, enhancement of photoreactivity by C5 methylation was much higher in the UVB than in the UVC range. These results show the drastic effect of the methylation site on the photochemistry of cytosine. This article is protected by copyright. All rights reserved.
      PubDate: 2014-10-15T10:42:04.717219-05:
      DOI: 10.1111/php.12365
  • Solar UV Irradiances Modulate Effects of Ocean Acidification on the
           Coccolithophorid Emiliania huxleyi
    • Authors: Kai Xu; Kunshan Gao
      Pages: n/a - n/a
      Abstract: Emiliania huxleyi, the most abundant coccolithophorid in the oceans, is naturally exposed to solar UV radiation (UVR, 280‐400 nm) in addition to photosynthetically active radiation (PAR). We investigated the physiological responses of E. huxleyi to present‐day and elevated CO2 (390 vs 1000 μatm; with pHNBS 8.20 vs 7.86) under indoor constant PAR and fluctuating solar radiation with or without UVR. Enrichment of CO2 stimulated the production rate of particulate organic carbon (POC) under constant PAR, but led to unchanged POC production under incident fluctuating solar radiation. The production rates of particulate inorganic carbon (PIC) as well as PIC/POC ratios were reduced under the elevated CO2, ocean acidification (OA) condition, regardless of PAR levels and the presence of UVR. However, moderate levels of UVR increased PIC production rates and PIC/POC ratios. OA treatment interacted with UVR to influence the alga's physiological performance, leading to reduced specific growth rate in the presence of UVA (315‐400 nm) and decreased quantum yield, along with enhanced non‐photochemical quenching, with addition of UVB (280‐315 nm). The results clearly indicate that UV radiation needs to be invoked as a key stressor when considering the impacts of ocean acidification on E. huxleyi. This article is protected by copyright. All rights reserved.
      PubDate: 2014-10-15T10:41:52.568895-05:
      DOI: 10.1111/php.12363
  • Recent Advances in the Application of Chlorophyll a Fluorescence from
           Photosystem II
    • Authors: Ya Guo; Jinglu Tan
      Pages: n/a - n/a
      Abstract: In the photosynthesis process, part of the absorbed photon energy in photosystem II (PSII) may be re‐emitted as chlorophyll a fluorescence (ChlF). Environmental and plant physiological changes affect the emission of ChlF, which makes ChlF a potentially useful tool to sense these changes. Volumes of research on ChlF are published each year and some published work has been controversial. In order to facilitate the application of ChlF, it is important to have a holistic picture of the field. This review summarizes ChlF applications published in the last 10 years. This article is protected by copyright. All rights reserved.
      PubDate: 2014-10-14T11:59:22.095521-05:
      DOI: 10.1111/php.12362
  • DNA damage checkpoint responses in the S phase of synchronized diploid
           human fibroblasts
    • Authors: Paul D. Chastain; Bruna P. Brylawski, Yingchun C. Zhou, Shangbang Rao, Haitao Chu, Joseph G. Ibrahim, William K. Kaufmann, Marila Cordeiro‐Stone
      Pages: n/a - n/a
      Abstract: We investigated the hypothesis that the strength of the activation of the intra‐S DNA damage checkpoint varies within the S phase. Synchronized diploid human fibroblasts were exposed to either 0 or 2.5 J/m2 UVC in early, mid‐ and late‐S phase. The endpoints measured were the following: (I) radio‐resistant DNA synthesis (RDS), (II) induction of Chk1 phosphorylation, (III) initiation of new replicons, and (IV) length of replication tracks synthesized after irradiation. RDS analysis showed that global DNA synthesis was inhibited by approximately the same extent (30±12%), regardless of when during S phase the fibroblasts were exposed to UVC. Western blot analysis revealed that the UVC‐induced phosphorylation of Chk1 on serine 345 was high in early and mid S but 10‐fold lower in late S. DNA fiber immunostaining studies indicated that the replication fork displacement rate decreased in irradiated cells at the three time points examined; however, replicon initiation was inhibited strongly in early and mid S, but this response was attenuated in late S. These results suggest that the intra‐S checkpoint activated by UVC‐induced DNA damage is not as robust toward the end of S phase in its inhibition of the latest firing origins in human fibroblasts. This article is protected by copyright. All rights reserved.
      PubDate: 2014-10-14T11:43:28.655937-05:
      DOI: 10.1111/php.12361
  • Electronic Interactions of Michler's Ketone with DNA Bases in Synthetic
    • Authors: Almaz S. Jalilov; Ryan M. Young, Samuel W. Eaton, Michael R. Wasielewski, Frederick D. Lewis
      Pages: n/a - n/a
      Abstract: The mechanism and dynamics of photoinduced electron transfer in two families of DNA hairpins possessing Michler's Ketone linkers have been investigated by means of steady state and time‐resolved transient absorption and emission spectroscopies. The excited state behavior of the diol linker employed in hairpin synthesis is similar to that of Michler's ketone in methanol solution. Hairpins possessing only a Michler's ketone linker undergo fast singlet state charge separation and charge recombination with an adjacent purine base, attributed to well‐stacked ground state conformations, and intersystem crossing to the triplet state, attributed to poorly‐stacked ground state conformations. The failure of the triplet to undergo electron transfer reactions on the 7 ns time scale of our measurements is attributed to the low triplet energy and reduction potential of the twisted triplet state. Hairpins possessing both a Michler's ketone linker and a perylenediimide base surrogate separated by four base pairs undergo photoinduced hole transport from the diimide to Michler's ketone upon excitation of the diimide. The efficiency of hole transport is dependent upon the sequence of the intervening purine bases. This article is protected by copyright. All rights reserved.
      PubDate: 2014-10-08T10:41:22.009619-05:
      DOI: 10.1111/php.12360
  • Oculocutaneous Albinism in Sub‐Saharan Africa: Adverse
           Sun‐Associated Health Effects and Photoprotection
    • Authors: Caradee Y. Wright; Mary Norval, Richard W. Hertle
      Pages: n/a - n/a
      Abstract: Oculocutaneous albinism (OCA) is a genetically inherited autosomal recessive condition. Individuals with OCA lack melanin and therefore are susceptible to the harmful effects of solar ultraviolet radiation, including extreme sun sensitivity, photophobia and skin cancer. OCA is a grave public health issue in sub‐Saharan Africa with a prevalence as high as 1 in 1 000 in some tribes. This article considers the characteristics and prevalence of OCA in sub‐Saharan African countries. Sun‐induced adverse health effects in the skin and eyes of OCA individuals are reviewed. Sun exposure behaviour and the use of photoprotection for the skin and eyes are discussed to highlight the major challenges experienced by these at‐risk individuals and how these might be best resolved. This article is protected by copyright. All rights reserved.
      PubDate: 2014-10-08T10:41:07.506343-05:
      DOI: 10.1111/php.12359
  • Interspecific Variation in the Repair of UV Damaged DNA in the Genus
           Xiphophorus as a Factor in the Decline of the Rio Grande Platyfish
    • Authors: David Mitchell; Lakshmi Paniker, Kevin Lin, André Fernandez
      Pages: n/a - n/a
      Abstract: The fish genus Xiphophorus consists of 26 species distributed along the eastern slopes of mountain ranges extending from northern Mexico to Belize and Nicaragua. We analyzed light‐dependent repair of UV‐induced DNA damage in at least two species from each of the four monophyletic Xiphophorus groups. We found that the northern platyfish had significantly reduced photoenzymatic repair compared to the other three groups, including the northern swordtails, southern platyfish and southern swordtails. All of the species of the platyfish, including the Marbled (meyeri), Northern (gordoni) and Monterrey Platyfish (couchianus) are the northernmost species in the genus and are the only three species in the genus that are currently found on the IUCN Red List of Threatened Species. Satellite data from the past 30 years (1979‐2008) correlates greater increases in shorter wavelength UVB with higher latitudes within the Xiphophorus range. We suggest that, combined with other consequences of human population growth, anthropogenic deozonation resulting in a disproportionate increase in UVB in temperate latitudes may be a contributing factor in the decline and extirpation of the northern platyfish. This article is protected by copyright. All rights reserved.
      PubDate: 2014-10-08T10:40:55.879868-05:
      DOI: 10.1111/php.12358
  • Photostability of Cosmetic UV Filters on Mammalian Skin Under UV Exposure
    • Authors: Constanze Stiefel; Wolfgang Schwack, Yen‐Thi Hai Nguyen
      Pages: n/a - n/a
      Abstract: Previous studies showed that the common UV filter substances benzophenone‐3 (BP–3), butyl methoxydibenzoylmethane (BM–DBM), octocrylene (OCR), ethylhexyl methoxycinnamate (EHMC), ethylhexyl salicylate (EHS), and ethylhexyl triazone (EHT) were able to react with amino side chains of different proteins in vitro. To transfer the results to mammalian skin conditions, sunscreen products were applied on both prepared fresh porcine skin and glass plates, followed by UV irradiation and the determination of depletion of the respective UV filters. Significantly lower recoveries of the UV filters extracted from skin samples than from glass plates indicated the additional reaction of the UV filters with skin constituents, when proteins will be the most important reactants. Among the products tested, BP‐3 showed the greatest differences in recoveries between glass and skin samples of about 13% and 24% after 2 and 4 h of irradiation, respectively, followed by EHS > BM‐DBM > OCR > EHMC > EHT. The obtained results raise the question, whether the common in vitro evaluations of sunscreens, using inert substrate materials like roughened quartz or polymethyl methacrylate (PMMA) plates are really suitable to fully replace in vivo methods, since they cannot include skin‐typical reactions. This article is protected by copyright. All rights reserved.
      PubDate: 2014-10-05T06:23:21.603512-05:
      DOI: 10.1111/php.12357
  • Inspection of Feasible Calibration Conditions for UV Radiometer Detectors
           with the KI/KIO3 Actinometer
    • Authors: Zhimin Qiang; Wentao Li, Mengkai Li, James R. Bolton, Jiuhui Qu
      Pages: n/a - n/a
      Abstract: UV radiometers are widely employed for irradiance measurements, but their periodical calibrations not only induce an extra cost but also are time‐consuming. In this study, the KI/KIO3 actinometer was applied to calibrate UV radiometer detectors at 254 nm with a quasi‐collimated beam apparatus equipped with a low‐pressure UV lamp, and feasible calibration conditions were identified. Results indicate that a washer constraining the UV light was indispensable, while the size (10 or 50 mL) of a beaker containing the actinometer solution had little influence when a proper washer was used. The absorption or reflection of UV light by the internal beaker wall led to an underestimation or overestimation of the irradiance determined by the KI/KIO3 actinometer, respectively. The proper range of the washer internal diameter could be obtained via mathematical analysis. A radiometer with a longer service time showed a greater calibration factor. To minimize the interference from the inner wall reflection of the collimating tube, calibrations should be conducted at positions far enough away from the tube bottom. This study demonstrates that after the feasible calibration conditions are identified, the KI/KIO3 actinometer can be applied readily to calibrate UV radiometer detectors at 254 nm. This article is protected by copyright. All rights reserved.
      PubDate: 2014-10-05T06:23:07.803221-05:
      DOI: 10.1111/php.12356
  • Photoactive chitosan: A step towards a green strategy for pollutant
    • Authors: Niluksha Walalawela; Alexander Greer
      Pages: n/a - n/a
      Abstract: This article is a highlight of the paper by Ferrari et al. in this issue of Photochemistry and Photobiology. It describes the innovative use of rose bengal‐conjugated chitosan as a reusable green catalyst that photo‐degrades phenolic compounds in aqueous media, and thereby has decontamination potential of polluted waters. Whether a next‐generation photoactive polymer that produces singlet oxygen is a solution to pollutant degradation can be argued. It is as yet unclear what polymeric sensitizer would be practical on a large scale. Nonetheless pursuing this goal is worthwhile. This article is protected by copyright. All rights reserved.
      PubDate: 2014-10-01T01:37:42.714394-05:
      DOI: 10.1111/php.12355
  • Opsin Expression in Human Epidermal Skin
    • Authors: Kirk Haltaufderhyde; Rana N. Ozdeslik, Nadine L. Wicks, Julia A. Najera, Elena Oancea
      Pages: n/a - n/a
      Abstract: Human skin is constantly exposed to solar light containing visible and ultraviolet radiation (UVR), a powerful skin carcinogen. UVR elicits cellular responses in epidermal cells via several mechanisms: direct absorption of short wavelength UVR photons by DNA, oxidative damage caused by long wavelength UVR, and, as we recently demonstrated, via a retinal‐dependent G protein‐coupled signaling pathway. Because the human epidermis is exposed to a wide range of light wavelengths, we investigated whether opsins, light‐activated receptors that mediate photoreception in the eye, are expressed in epidermal skin to potentially serve as photosensors. Here we show that four opsins — OPN1‐SW, OPN2, OPN3 and OPN5 — are expressed in the two major human epidermal cell types, melanocytes and keratinocytes, and the mRNA expression profile of these opsins does not change in response to physiological UVR doses. We detected two OPN3 splice variants present in similar amounts in both cell types and three OPN5 splice isoforms, two of which encode truncated proteins. Notably, OPN2 and OPN3 mRNA were significantly more abundant than other opsins and encoded full‐length proteins. Our results demonstrate that opsins are expressed in epidermal skin cells and suggest that they might initiate light‐induced signaling pathways, possibly contributing to UVR phototransduction. This article is protected by copyright. All rights reserved.
      PubDate: 2014-09-30T05:57:43.835219-05:
      DOI: 10.1111/php.12354
  • Comparison of Templating Abilities of Urea and Thioruea During
           Photodimerization of Bipyridylethyelene and Stilbazole Crystals
    • Authors: Balakrishna R. Bhogala; Burjor Captain, V. Ramamurthy
      Pages: n/a - n/a
      Abstract: Photodimerization of co‐crystals of four bispyridylethylenes and two stilbazoles with urea as a template in the solid state has been investigated following our success with thiourea. Four investigated olefins photodimerized quantitatively to a single dimer in the crystalline state only. The reactivity of urea‐olefin crystals is understood on the basis of their packing arrangements in the crystalline state. In reactive crystals the adjacent reactive molecules are within 4.2 Å and parallel, while the unreactive ones have their adjacent molecules are farther than 4.6Å and non‐parallel. Thus, with the knowledge of crystal packing the reactivity of urea‐olefin crystals is predictable on the basis of Schmidt's topochemical postulates. The templating property of urea, similar to thiourea, derives from its ability to form hydrogen bonds with itself and the guest olefins. Despite the similarities in molecular structures of urea and thiourea their subtle electronic properties, yet to be fully understood, affect the crystal packing and consequently their reactivity in the crystalline state. Further work is needed to fully exploit the templating properties of urea. This article is protected by copyright. All rights reserved.
      PubDate: 2014-09-28T21:12:25.943849-05:
      DOI: 10.1111/php.12353
  • Highly efficient Photodegradation of Organic Pollutants Assisted by
    • Authors: Anna V. Volkova; Silke Nemeth, Ekaterina V. Skorb, Daria V. Andreeva
      Pages: n/a - n/a
      Abstract: The mechanism of the photodegradation of azo dyes via ultrasonication is studied using a combination of the high‐performance liquid chromatography and UV‐vis spectroscopy with detailed analysis of the process kinetics. Based on the kinetics studies of the sonodegradation process it was proposed that the sonodegradation of azo dyes was a multistage process that involved: i) the direct attack of azo bonds and phenyl rings of dyes by the sonochemically formed reactive oxygen species; ii) the activation of semiconductor particles by the light emitted during cavitation and the triggering of the photocatalytic pathways of dye degradation; iii) increase of the adsorption capacity of the semiconductor particles due to the sono mechanically induced inter particle collisions. The detailed kinetics study can help in following an effective process up‐scaling. It was demonstrated that extremely short pulses of light flashes in a cavitated mixture activated the surface of photocatalysts and significantly enhanced dye degradation processes. This article is protected by copyright. All rights reserved.
      PubDate: 2014-09-26T05:42:46.445568-05:
      DOI: 10.1111/php.12352
  • Interleukin‐17 Mediated Inflammatory Responses Are Required for
           Ultraviolet Radiation Induced Immune Suppression;
    • Authors: Hui Li; Ram Prasad, Santosh K. Katiyar, Nabiha Yusuf, Craig A. Elmets, Hui Xu
      Pages: n/a - n/a
      Abstract: Ultraviolet radiation (UVR) induces immunosuppression and is a major factor for development of skin cancer. Numerous efforts have been made to determine mechanisms for UVR induced immunosuppression and to develop strategies for prevention and treatment of UVR induced cancers. In the current study, we use IL‐17 receptor (IL‐17R) deficient mice to examine whether IL‐17 mediated responses have a role in UVB (290‐320) induced immunosuppression of contact hypersensitivity responses. Results demonstrate that IL‐17 mediated responses are required for UVB induced immunosuppression of contact hypersensitivity responses. The systemic immune suppression and development of regulatory T cells are inhibited in UVB treated IL‐17R deficient mice compared to wild type animals. The deficiency in IL‐17R inhibits the infiltration and development of a tolerogenic myeloid cell population in UVB treated skin, which expresses CD11b and Gr‐1 and produces reactive oxygen species. We speculate that the development of the tolerogenic myeloid cells is dependent on IL‐17 induced chemokines and inflammatory mediators in UVB treated skin. The inhibition of the tolerogenic myeloid cells may be attributed to the suppression of regulatory T cells in UVR treated IL‐17R‐/‐ mice. The findings may be exploited to new strategies for prevention and treatment of UVR induced skin diseases and cancers. This article is protected by copyright. All rights reserved.
      PubDate: 2014-09-23T10:18:18.213881-05:
      DOI: 10.1111/php.12351
  • The employment of a removable chitosan‐derivatized polymeric
           sensitizer in the photooxidation of polyhydroxylated
    • Authors: Gabriela V. Ferrari; María E. Andrada, José Natera, Vanesa A. Muñoz, M. Paulina Montaña, Carolina Gambetta, María L Boiero, Mariana A. Montenegro, Walter A. Massad, Norman A. García
      Pages: n/a - n/a
      Abstract: The known O2(1Δg)‐sensitizer system Chitosan bounded Rose Bengal (CH‐RB), with Rose Bengal (RB) immobilized by irreversible covalent bonding to the polymer Chitosan (CH), soluble in aquous acidic medium, was employed in the photodegradation of three tri‐hydroxy benzene water‐contaminants (THBs). The system sensitizes the O2(1Δg)‐mediated photodegradation of THBs by a process kinetically favored, as compared to that employing free RB dissolved in the same solvent. Additionally the free xanthene dye, degradable by O2(1Δg) through self‐sensitization upon prolonged light‐exposure, is considerably protected when bonded to CH‐polymer. The polymeric sensitizer, totally insoluble in neutral medium, can be removed from the solution after the photodegradative cycle by precipitation through a simple pH change. This fact constitutes an interesting aspect in the context of photoremediation of confined polluted waters. In other words, the sensitizing system could be useful for avoiding to dissolve dyestuffs in the polluted waters, in order to act as conventional sunlight‐absorbing dye‐sensitizers. In parallel the interaction CH ‐ O2(1Δg) in acidic solution was evaluated. The polymer quenches the oxidative species with a rate constant 2.4x108 M−1s−1 being the process mostly attributable to a physical interaction. This fact promotes the photoprotection of the bonded dye in the CH‐RB polymer. This article is protected by copyright. All rights reserved.
      PubDate: 2014-09-20T09:11:29.130189-05:
      DOI: 10.1111/php.12350
  • Sun Exposure and Vitamin D Status as Northeast Asian Migrants Become
           Acculturated to Life in Australia
    • Authors: Shuyu Guo; Peter Gies, Kerryn King, Robyn M Lucas
      Pages: n/a - n/a
      Abstract: Vitamin D deficiency is more common in Northeast‐Asian immigrants to western countries than in the local population; prevalence equalizes as immigrants adopt the host country's culture. In a community‐based study of 100 Northeast‐Asian immigrants in Canberra, Australia, we examined predictors of vitamin D status, its association with indicators of acculturation (English language use; time since migration) and mediators of that association. Participants completed a sun and physical activity diary and wore an electronic ultraviolet radiation (UVR) dosimeter for 7 days. Skin colour was measured by reflectance spectrophotometry. Serum concentrations of 25‐hydroxyvitamin D (25(OH)D) and cardio‐metabolic biomarkers were measured on fasting blood. In a multiple linear regression model, predictors for 25(OH)D concentration were season of blood collection, vitamin D supplementation, UVR exposure, body mass index, physical activity and having private health insurance (R2=0.57). Greater acculturation was associated with lower risk of vitamin D deficiency (de‐seasonalized 25(OH)D level 5.0mmol/L) (AOR: 7.48 (95%CI 1.51‐37.0)). Targeted public health approaches are required to manage the high prevalence of vitamin D deficiency in migrants retaining a traditional lifestyle. This article is protected by copyright. All rights reserved.
      PubDate: 2014-09-20T00:39:58.163801-05:
      DOI: 10.1111/php.12349
  • Skin Responses to Micro Scale Field Size of Solar‐Simulated
           Radiation – Preliminary Evaluation by Reflectance Confocal
           Microscopy in vivo
    • Authors: InSeok Seo; Melissa Chu, Paulo R. Bargo, Nikiforos Kollias
      Pages: n/a - n/a
      Abstract: Erythema and pigment responses of human skin following an acute exposure to ultraviolet radiation (UVR) are frequently used to determine the photosensitivity of the skin. In this study we investigated the responses of the skin to a micro‐scale area of UVR exposure (MiR) and compared the responses to a macro‐scale area of exposure (MaR). Ten human volunteers were tested with solar‐simulated radiation on their upper arm or back using a beam size of 8mm and 0.2mm in diameter. The fluence required to produce a minimally perceptible erythema (MED) using the MiR was found to be higher than that for the MaR. The erythema response extended beyond the exposed area and this became pronounced when the beam size was microscopic. Reflectance confocal microscopy in vivo revealed that MiR induced cellular alterations within a confined area of smaller dimensions than the area of exposure. Pigment responses were confined within the areas of cellular damage. The erythema expression of exposed skin recovered faster for the sites receiving MiR even when the applied fluence was higher than the MED for the MaR. Through the use of MiR we were able to visualize spatially dissimilar skin responses of erythema and pigmentation suggesting different cellular mechanisms. This article is protected by copyright. All rights reserved.
      PubDate: 2014-09-20T00:39:43.036009-05:
      DOI: 10.1111/php.12348
  • Improving Photoprotection Attitudes in the Tropics: Sunburn vs Vitamin D
    • Authors: Abel A. Silva
      Pages: n/a - n/a
      Abstract: The ultraviolet radiation of type B (the UVB) stimulates both the production of vitamin D (VD) and the incorporation of erythema dose (ED). The UVA also contributes to ED. The turning point between the benefit of producing VD and the harm of incorporating ED cannot be determined easily. However, the casual behavior regarding the exposure to the Sun can be changed in order to improve the protoprotection attitudes and create a trend towards benefit. In the case, people living in the low latitudes should exposure themselves to the Sun for a determined time interval within the noon time and avoid the Sun in other periods. This would produce an adequate amount of VD through the VD dose (207‐214 J/m2) against minimum ED (≈ 105 J/m2) for skin type II. For it, unprotected forearms and hands must be exposed to the noon Sun (cloudless) for 11 min (winter) and 5 min (summer). The exposure at other times different from noon can represent increases of up to 24% in ED and up to 12 times in the time interval to be in the Sun in relation to the minimum amounts of both ED and time interval at noon. This article is protected by copyright. All rights reserved.
      PubDate: 2014-09-20T00:39:35.875264-05:
      DOI: 10.1111/php.12347
  • MicroRNAs and Photocarcinogenesis
    • Authors: Deeba N. Syed; Rahul K. Lall, Hasan Mukhtar
      Pages: n/a - n/a
      Abstract: As a new class of sequence‐specific regulators of gene expression, the microRNAs (miRNA) form a regulatory network with growth factors and transcription factors participating in various biological processes. It is now being recognized that the various key processes involved in cancer induction are under the control of these small non‐coding RNAs, which regulate ~30% of all human genes by targeting sequences in their 3′‐untranslated regions. Photocarcinogenesis is a complex interplay of signaling events in the UV exposed human skin including DNA damage and repair, apoptosis, cell survival, mutations and the immune system. In this review, we have scrutinized the role of miRNAs in skin cancer biology focusing on the three most common types of skin cancer namely the basal cell carcinoma, squamous cell carcinoma and cutaneous malignant melanoma. An overview of these studies will be useful in gaining insights into the mechanisms of cancer development in the human skin. A better understanding of the functionality of miRNAs will have enormous implications to risk assessment, and to target interventions against signaling events involved in photocarcinogenesis. This article is protected by copyright. All rights reserved.
      PubDate: 2014-09-16T19:50:11.367591-05:
      DOI: 10.1111/php.12346
  • Forty Years of Research on Xeroderma Pigmentosum at the US National
           Institutes of Health
    • Authors: Kenneth H. Kraemer; John J. DiGiovanna
      Pages: n/a - n/a
      Abstract: In 1968, Dr. James Cleaver reported defective DNA repair in cultured cells from patients with xeroderma pigmentosum. This link between clinical disease and molecular pathophysiology has sparked interest in understanding not only the clinical characteristics of sun sensitivity, damage and cancer that occurred in XP patients but also the mechanisms underlying the damage and repair. While affected patients are rare, their exaggerated UV damage provides a window into the workings of DNA repair. These studies have clarified the importance of a functioning DNA repair system to the maintenance of skin and neurologic health in the general population. Understanding the role of damage in causing cancer, neurologic degeneration, hearing loss and internal cancers provides an opportunity for prevention and treatment. Characterizing complementation groups pointed to the importance of different underlying genes. Studying differences in cancer age of onset and underlying molecular signatures in cancers occurring either in XP patients or the general population has led to insights into differences in carcinogenic mechanisms. The accelerated development of cancers in XP has been used as a model to discover new cancer chemopreventive agents. An astute insight can be a “tipping point” triggering decades of productive inquiry. This article is protected by copyright. All rights reserved.
      PubDate: 2014-09-15T03:16:16.941709-05:
      DOI: 10.1111/php.12345
  • The Effects of NO3‐ Supply on Mazzaella laminarioides (Rhodophyta,
           Gigartinales) from Southern Chile
    • Authors: Nelso P. Navarro; Félix L. Figueroa, Nathalie Korbee, Andrés Mansilla, Betty Matsuhiro, Tamara Barahona, Estela M. Plastino
      Pages: n/a - n/a
      Abstract: The effects of nitrate supply on growth, pigments, mycosporine‐like amino acids (MAAs), C:N ratios, and carrageenan yield were investigated in Mazzaella laminarioides cultivated under solar radiation. This species is economically important in southern Chile where an increase of nitrogen in coastal waters is expected as a consequence of salmon aquaculture activity. Apical segments were cultivated in enriched seawater with five different NO3− concentrations (0, 0.09, 0.18, 0.38, and 0.75 mM) during 18 days. Although phycoerythrin and phycocyanin content, as well as C:N ratios, were reduced in the control treatment (without NO3− supply), when compared to NO3‐ treatments, total MAA concentration, carrageenan yield, and growth rates were similar in all tested conditions. Nevertheless, during the experiment, an important synthesis of mycosporine‐glycine took place in a nitrate concentration‐dependent manner, with accumulation being saturated around 0.18 mM of nitrate. These results indicate that exposure to high NO3− concentration of more than 100 times the values observed in the nature did not impair the photoprotection system, as determined by MAAs, nor did it have a deleterious effect on growth or carrageenan yield of M. laminarioides, a late successional species from Chile. This article is protected by copyright. All rights reserved.
      PubDate: 2014-09-11T11:17:33.355365-05:
      DOI: 10.1111/php.12344
  • Development of refractoriness of HO‐1 induction to a second
           treatment with UVA radiation and the involvement of Nrf2 in human skin
    • Authors: Julia Li Zhong; Chintan M. Raval, Muhammad Farrukh Nisar, ChunXiang Bian, Jin Zhang, Li Yang, Rex M. Tyrrell
      Pages: n/a - n/a
      Abstract: UVA treatment of cultured human skin fibroblasts (FEK4) has been shown previously to reduce transcriptional activation of hemeoxygenase 1 (HO‐1) following a second dose of UVA radiation, a phenomenon known as refractoriness. This study demonstrates that the levels of HO‐1 protein are also reduced after a second dose of UVA radiation as are Nrf2 levels, and there is less accumulation of Nrf2 in the nucleus where as Bach1 does accumulate in the nucleus. Cell viability is further reduced and cell membrane damage increased as compared with a single UVA treatment when an initial UVA treatment was followed by a second dose. Knockdown of Nrf2 by siRNA (siNrf2) targeting caused additional refractoriness of HO‐1 protein induction to a second UVA or heme treatment and this treatment also further enhanced cell damage by a second dose of UVA radiation. However, transfection with Nrf2 caused less refractoriness of HO‐1 to a second dose of UVA and reduced cell damage by a second dose of UVA radiation. These findings are consistent with the proposal that Nrf2 is involved in HO‐1 refractoriness and could serve as a cytoprotective factor against cell damage caused by repeated exposure to moderate doses of UVA radiation. We propose that protection by the Nrf2‐HO‐1 pathway protection may have clinical relevance since human skin is exposed repeatedly to UVA radiation. This article is protected by copyright. All rights reserved.
      PubDate: 2014-09-11T11:17:10.201108-05:
      DOI: 10.1111/php.12343
  • UVA irradiation induced heme oxygenase‐1 (HO‐1): A novel
           phototherapy for morphea
    • Authors: Muhammad Farrukh Nisar; Kimberly Suzanne George Parsons, Chun Xiang Bian, Julia Li Zhong
      Pages: n/a - n/a
      Abstract: Long wave UVA radiation (340‐400 nm) causes detrimental as well as beneficial effects on human skin. Studies of human skin fibroblasts irradiated with UVA demonstrate increased expression of both anti‐fibrotic heme oxygenase‐1 (HO‐1) and matrix metalloproteinase 1 (MMP‐1). The use of UVA ‐induced MMP‐1 is well studied in treating skin fibrotic conditions such as localised scleroderma, now called morphea. However, the role that UVA‐induced HO‐1 plays in phototherapy of morphea has not been characterized. In the present manuscript, we have illustrated and reviewed the biological function of HO‐1 and the use of UVA1 wavebands (340‐400 nm) for phototherapy; the potential use of HO‐1 induction in UVA therapy of morphea is also discussed. This article is protected by copyright. All rights reserved.
      PubDate: 2014-09-10T07:22:05.461981-05:
      DOI: 10.1111/php.12342
  • Photo‐Wolff Rearrangement of
           2‐Diazo‐1,2‐naphthoquinone: Stern–Volmer Analysis
           of the Stepwise Reaction Pathway;
    • Authors: Manfred Ladinig; Markus Ramseier, Jakob Wirz
      Pages: n/a - n/a
      Abstract: 2‐Diazo‐1,2‐naphthoquinone (1) and its derivatives are the photoactive components in Novolak photoresists. A femtosecond infrared study has established that the photoreaction of 1 proceeds largely by a concerted Wolff‐rearrangement yielding the ketene 1H‐inden‐1‐ylidene‐methanone (3) within 300 fs after excitation, but earlier trapping studies gave evidence for a minor reaction path via a carbene intermediate 1‐oxo‐2(1H)‐naphthalenylidene (2) with a lifetime of about 10 ps. Here, we provide a quantitative assessment of the stepwise pathway by Stern–Volmer analysis of the trapping of 2 by methanol to yield 2‐methoxy‐1‐naphthol (4). We conclude that the lifetime of the carbene 2 is at least 200 ps. Moreover, [3+2]cycloaddition of 2 and acetonitrile yielding 2‐methylnaphth[2,1‐d]oxazole (5) was observed. A comparison of the yields of 5 formed upon photolysis and upon thermolysis of 1 in acetonitrile provides evidence that a substantial part of the hot nascent carbene 2 formed photolytically rearranges to the ketene 3 during its vibrational relaxation (hot ground state reaction). This article is protected by copyright. All rights reserved.
      PubDate: 2014-09-05T10:25:51.45167-05:0
      DOI: 10.1111/php.12341
  • Specific Features of the Early Stage of the Wound Healing Process
           Occurring Against the Background of Photodynamic Therapy Using Fotoditazin
           Photosensitizer‐Amphiphilic Polymer Complexes
    • Authors: Tatiana G. Rudenko; Anatoly B. Shekhter, Anna E. Guller, Nadezhda A. Aksenova, Nikolay N. Glagolev, Andrey V. Ivanov, Ruben K. Aboyants, Svetlana L. Kotova, Anna B. Solovieva
      Pages: n/a - n/a
      Abstract: There is a growing demand on the studies of the wound healing potentials of photodynamic therapy. Here we analyze the effects of Fotoditazin, an e6 chlorine derivative, and its complexes with amphiphilic polymers, on the early stage of wound healing in a rat model. A skin excision wound model with prevented contraction was developed in male albino rats divided into 8 groups according to the treatment mode. All animals received injections of one of the studied compositions into their wound beds and underwent low intensity laser irradiation or stayed un‐irradiated. The clinical monitoring and histological examination of the wounds were performed. It has been found that all the Fotoditazin formulations have significant effects on the early stage of wound healing. The superposition of the inflammation and regeneration was the main difference between groups. The aqueous solution of Fotoditazin alone induced a significant capillary haemorrhage, while its combinations with amphiphilic polymers did not. The best clinical and morphological results were obtained for the Fotoditazin‐Pluronic F127 composition. Compositions of Fotoditazin and amphiphilic polymers, especially Pluronic F127, probably, have a great potential for therapy of wounds. Their effects can be attributed to the increased regeneration and suppressed reactions changes at the early stages of repair. This article is protected by copyright. All rights reserved.
      PubDate: 2014-09-03T01:25:53.682715-05:
      DOI: 10.1111/php.12340
  • Photophysical Properties and Singlet Oxygen Generation Efficiencies of
           Water‐Soluble Fullerene Nanoparticles
    • Authors: Alexander S. Stasheuski; Victor A. Galievsky, Alexander P. Stupak, Boris M. Dzhagarov, Mi Jin Choi, Bong Hyun Chung, Jin Young Jeong
      Pages: n/a - n/a
      Abstract: As various fullerene derivatives have been developed, it is necessary to explore their photophysical properties for potential use in photoelectronics and medicine. Here, we address the photophysical properties of newly synthesized water‐soluble fullerene‐based nanoparticles and polyhydroxylated fullerene as a representative water‐soluble fullerene derivative. They show broad emission band arising from a wide‐range of excitation energies. It is attributed to the optical transitions from disorder‐induced states, which decay in the nanosecond time range. We determine the kinetic properties of the singlet oxygen (1O2) luminescence generated by the fullerene nanoparticles and polyhydroxylated fullerene to consider the potential as photodynamic agents. Triplet state decay of the nanoparticles was longer than 1O2 lifetime in water. Singlet oxygen quantum yield of a series of the fullerene nanoparticles is comparably higher ranging from 0.15 to 0.2 than that of polyhydroxylated fullerene, which is about 0.06. Conventional and time‐resolved spectroscopy has been used to investigate polyhydroxylfullerene molecule and five fullerene‐based nanoparticles. Our results demonstrate formation of disorder‐induced states both in the polyhydroxylfullerene and in the nanoparticles.
      PubDate: 2014-08-31T23:51:52.763771-05:
      DOI: 10.1111/php.12294
  • Photocatalytic degradation of glyphosate in water by N–doped
           SnO2/TiO2 thin film coated glass fibers
    • Authors: Peerawas Kongsong; Lek Sikong, Sutham Niyomwas, Vishnu Rachpech
      Pages: n/a - n/a
      Abstract: Photocatalytic degradation of glyphosate contaminated in water was investigated. The N–doped SnO2/TiO2 films were prepared via sol–gel method, and coated on glass fibers by dipping method. The effects of nitrogen doping on coating morphology, physical properties, and glyphosate degradation rates were experimentally determined. Main variable was the concentration of nitrogen doping in range 0–40 mol%. Nitrogen doping results in shifting the absorption wavelengths and narrowing the band gap energy those lead to enhancement of photocatalytic performance. The near optimal 20N/SnO2/TiO2 composite thin film exhibited about 2 and 4 folds of glyphosate degradation rates compared to the undoped SnO2/TiO2 and TiO2 films when photocatalytic treatment were performed under UV and solar irradiations, respectively due to its narrowest band gap energy (optical absorption wavelength shifting to visible light region) and smallest crystallite size influenced by N doping. This article is protected by copyright. All rights reserved.
      PubDate: 2014-08-28T11:07:39.238249-05:
      DOI: 10.1111/php.12338
  • Fisetin inhibits UVB‐induced cutaneous inflammation and activation
           of PI3K/AKT/ NFκB signaling pathways in SKH‐1 hairless mice;
    • Authors: Harish Chandra Pal; Mohammad Athar, Craig A. Elmets, Farrukh Afaq
      Pages: n/a - n/a
      Abstract: Solar ultraviolet B (UVB) radiation has been shown to induce inflammation, DNA damage, p53 mutations, and alterations in signaling pathways eventually leading to skin cancer. In the present study, we investigated whether fisetin reduces inflammatory responses and modulates PI3K/AKT/NFκB cell survival signaling pathways in UVB exposed SKH‐1 hairless mouse skin. Mice were exposed to 180 mJ/cm2 of UVB radiation on alternate days for a total of seven exposures, and fisetin (250 and 500 nmol) was applied topically after 15 min of each UVB exposure. Fisetin treatment to UVB exposed mice resulted in decreased hyperplasia and reduced infiltration of inflammatory cells. Fisetin treatment also reduced inflammatory mediators such as COX‐2, PGE2 as well as its receptors (EP1‐ EP4), and MPO activity. Furthermore, fisetin reduced the level of inflammatory cytokines TNFα, IL‐1β and IL‐6 in UVB exposed skin. Fisetin treatment also reduced cell proliferation markers as well as DNA damage as evidenced by increased expression of p53 and p21 proteins. Further studies revealed that fisetin inhibited UVB‐induced expression of PI3K, phosphorylation of AKT, and activation of the NFκB signaling pathway in UVB exposed mouse skin. Overall, these data suggest that fisetin may be useful against UVB‐induced cutaneous inflammation and DNA damage. This article is protected by copyright. All rights reserved.
      PubDate: 2014-08-28T11:03:29.250842-05:
      DOI: 10.1111/php.12337
  • Simultaneous Irradiation with Different Wavelengths of Ultraviolet Light
           has Synergistic Bactericidal Effect on Vibrio parahaemolyticus
    • Authors: Mutsumi Nakahashi; Kazuaki Mawatari, Akiko Hirata, Miki Maetani, Takaaki Shimohata, Takashi Uebanso, Yasuhiro Hamada, Masatake Akutagawa, Yousuke Kinouchi, Akira Takahashi
      Pages: n/a - n/a
      Abstract: Ultraviolet (UV) irradiation is an increasingly used method of water disinfection. UV rays can be classified by wavelength into UVA (320–400 nm), UVB (280‐320 nm), and UVC (
      PubDate: 2014-08-28T06:58:03.637028-05:
      DOI: 10.1111/php.12309
  • Photocatalysis of chloroform decomposition by tetrachlorocuprate(II) on
           Dowex 2‐X8
    • Authors: Brent M. Harvey; Patrick E. Hoggard
      Pages: n/a - n/a
      Abstract: Heterogenized on a polystyrene anion exchange resin and in the presence of oxygen, CuCl42‐ catalyzes the photodecomposition of chloroform at wavelengths above 345 nm with greater efficiency than an equivalent amount in homogeneous solution. The reaction is proposed to proceed in two stages, the first stage yielding CCl4 and HO2ˉ as products, the second consisting of a chain reaction resulting from the CuCl42‐‐catalyzed photodissociation of CCl4, yielding phosgene with CCl3 radicals as chain carriers. Photodecomposition is retarded by added Clˉ, CH3CN, C6H12, and C2H5OH, which is ascribed to the displacement of CHCl3 molecules from the vicinity of the copper by attraction to the polystyrene matrix or to the alkylammonium cation sites. This article is protected by copyright. All rights reserved.
      PubDate: 2014-08-25T01:48:09.167989-05:
      DOI: 10.1111/php.12336
  • MC1R, Eumelanin and Pheomelanin: their role in determining the
           susceptibility to skin cancer;
    • Authors: Tahseen H. Nasti; Laura Timares
      Pages: n/a - n/a
      Abstract: Skin pigmentation is due to the accumulation of two types of melanin granules in the keratinocytes. Besides being the most potent blocker of ultraviolet radiation (UVR), the role of melanin in photo‐protection is complex. This is because one type of melanin called eumelanin is UV absorbent whereas the other, pheomelanin, is photo‐unstable and may even promote carcinogenesis. Skin hyperpigmentation may be caused by stress or exposure to sunlight, which stimulates the release of α‐melanocyte stimulating hormone (α‐MSH) from damaged keratinocytes. Melanocortin 1 receptor (MC1R) is a key signaling molecule on melanocytes that responds to α‐MSH by inducing expression of enzymes responsible for eumelanin synthesis. Persons with red hair have mutations in the MC1R causing its inactivation; this leads to a paucity of eumelanin production and makes red‐heads more susceptible to skin cancer. Apart from its effects on melanin production, the α‐MSH/MC1R signaling is also a potent anti‐inflammatory pathway and has been shown to promote anti‐melanoma immunity. This review will focus on the role of MC1R in terms of its regulation of melanogenesis and influence on the immune system with respect to skin cancer susceptibility. This article is protected by copyright. All rights reserved.
      PubDate: 2014-08-22T10:23:59.452431-05:
      DOI: 10.1111/php.12335
  • What Caused the Formation of the Absorption Maximum at 421 nm in vivo
           Spectra of Rhodopseudomonas palustris
    • Authors: Chungui Zhao; Huiying Yue, Qianru Cheng, Shicheng Chen, Suping Yang
      Pages: n/a - n/a
      Abstract: A spectral peak at ~421 nm appeared in vivo spectrum of Rhodopseudomonas palustris CQV97 cultured in acetate‐glutamate medium (M1) but not in acetate‐ammonium sulfate medium (M2). However, the spectral origin of 421 nm peak was unclear and frequently attributed to carotenoid component(s). In this study, comparative analysis of the extracted components showed that magnesium protoporphyrin IX monomethylester (MPE) was accumulated as one of the predominate components in M1 culture. The amounts of bacteriochlorophyll a in M1 culture were higher than that in M2 while the amounts of carotenoids were nearly identical in both cultures. A simple, rapid and minimum interference with carotenoid and bacteriochlorophyll method to efficiently extract the compounds involving in the formation of 421 nm peak was developed in this study. Assembly of purified MPE with protein components from R. palustris in vitro demonstrated that MPE caused the formation of 421 nm peak. The localization analysis in vivo demonstrated it is MPE associating to protein components and accounting for the peak at ~421 nm. This work clarified the 421 nm peak in vivo mainly originated from MPE accumulation, and will be very helpful to further explore the physiological roles of MPE or its derivatives in photosynthesis. This article is protected by copyright. All rights reserved.
      PubDate: 2014-08-22T10:23:42.936868-05:
      DOI: 10.1111/php.12334
  • Antitumor Effect of Sinoporphyrin sodium mediated Photodynamic Therapy on
           Human Esophageal Cancer Eca‐109 cells
    • Authors: Jianmin Hu; Xiaobing Wang, Quanhong Liu, Kun Zhang, Wenli Xiong, Chuanshan Xu, Pan Wang, Albert Wingnang Leung
      Pages: n/a - n/a
      Abstract: The aim of this study was to evaluate the photodynamic effect of Sinoporphyrin sodium (DVDMS). In this study, Eca‐109 cells were treated with DVDMS (5 μg/ml) and subjected to photodynamic therapy (PDT). The uptake and sub‐cellular localization of DVDMS were monitored by flow cytometry and confocal microscopy. The phototoxicity of DVDMS was studied by MTT assay. The morphological changes were observed by scanning electron microscopy (SEM). DNA damage, reactive oxygen species (ROS) generation and mitochondria membrane potential (MMP) changes were analyzed by flow cytometry. Studies demonstrated maximal uptake of DVDMS occurred within 3 hours, with a mitochondrial sub‐cellular localization. MTT assays displayed that DVDMS could be effectively activated by light and the phototoxicity was much higher than photofrin under the same conditions. In addition, SEM observation indicated that cells were seriously damaged after PDT treatment. Furthermore, activation of DVDMS resulted in significant increases in ROS production. The generated ROS played an important role in the phototoxicity of DVDMS. DVDMS mediated PDT (DVDMS‐PDT) also induced DNA damage and MMP loss. It is demonstrated that DVDMS mediated PDT is an effective approach on cell proliferation inhibition of Eca‐109 cells. This article is protected by copyright. All rights reserved.
      PubDate: 2014-08-20T07:08:45.390043-05:
      DOI: 10.1111/php.12333
  • Therapeutic Effect of Irradiation of Magnetic Infrared Laser on
           Osteoarthritis Rat Model
    • Authors: Chul‐Hwan Moon; Ogon Kwon, Chang‐Hoon Woo, Hee‐Duk Ahn, Young‐Sam Kwon, Soo‐Jin Park, Chang‐Hyun Song, Sae‐Kwang Ku
      Pages: n/a - n/a
      Abstract: Osteoarthritis (OA) is a degenerative joint disease caused by articular cartilage loss. Many complementary and alternative medicines for OA have been reported so far, but the effectiveness is controversial. Previously, we have shown anti‐inflammatory effects of low level laser therapy with static magnetic field, magnetic infrared laser (MIL), in various animal models. Therefore, the beneficial effects were examined in OA rat model. Rats were divided by six groups; no treatment controls of sham and OA model, three MIL treatment groups of OA model at 6.65, 2.66 and 1.33 J cm−2, and Diclofenac group of OA model with 2 mg kg−1 diclofenac sodium. The OA control exhibited typical symptoms of OA, but 4‐week MIL treatment improved the functional movement of knee joint with reduced edematous changes. In addition, cartilage GAGs were detected more in all MIL treatment groups than OA control. It suggests that 4‐week MIL irradiation has dose‐dependent anti‐inflammatory and chondroprotective effects on OA. Histopathological analyses revealed that MIL treatment inhibits the cartilage degradation and enhances chondrocyte proliferation. The fact that MIL has an additional potential for the cartilage formation and no adverse effects can be regarded as great advantages for OA treatment. These suggest that MIL can be useful for OA treatment. Eight rats per group received a surgical operation for osteoarthritis (OA) or sham. Controls for sham (A) and OA (B) had no treatment, and other OA models were treated with either of diclofenac sodium at 2 mg kg−1 (Diclofenac, C) as a reference or magnetic infrared laser (MIL) at 6.65 J cm−2 (D), 2.66 J cm−2 (E) and 1.33 J cm−2 (F) with constant magnetic field. Comparing to OA control, 4‐week MIL treatment improved maximum extension angle of knee joint dose dependently. Histopathological analyses revealed that the MIL treatment inhibits the cartilage degradation. Together with other results, these suggest that MIL can be useful for OA treatment.
      PubDate: 2014-08-19T00:52:22.87705-05:0
      DOI: 10.1111/php.12304
  • Short‐term UV‐B Dose Stimulates Production of Protective
           Metabolites in Matricaria chamomilla Leaves
    • Authors: Veronika Petruľová; Zuzana Dučaiová, Miroslav Repčák
      Pages: n/a - n/a
      Abstract: Physiological response of two cultivars of Matricaria chamomilla plants on UV irradiation was studied. The impact of used short‐time UV dose was evaluated in three time points; 2, 24 and 48 h after irradiation. Used UV irradiation immediately resulted in changes in plant oxidative status monitored as increased concentration of H2O2. Decrease in chlorophyll a and b indicated the impact on photosynthetic apparatus. For phenolic secondary metabolites, an increase in total soluble phenols and AlCl3‐reactive flavonols was observed. The activity of main phenolic enzyme, phenylalanine ammonia‐lyase, increased with time after irradiation. Significant changes, mainly decreasing trends, in the content of free coumarins and their glycosidic precursors were observed. Enhanced accumulation in chlorogenic and 1,5‐dicaffeoylquinic acid and in (Z)‐isoform of dicycloethers was detected. From these results, the redirecting precursors of coumarin biosynthesis to biosynthesis of substances with higher antioxidative potential can be assumed. Different reactions in diploid and tetraploid plants were recorded, too. Short‐term irradiation with UV‐A and UV‐B influenced some physiological processes (photosynthesis, enzyme activity) in 7‐week‐old rosette leaves of chamomile and stimulated protective response. Enhanced accumulation of simple phenylpropanoid derivatives, like chlorogenic and 1,5‐dicaffeoylquinic acid, coumarin glycoside, daphnin and flavonols related to UV‐stimulated PAL activity. Decreased content of free coumarins and their glycosides may indicate redirecting precursors of coumarin biosynthesis to biosynthesis of substances with higher antioxidative potential. Two chamomile cultivars, differed in ploidy level, were irradiated. Tetraploids were more damaged by oxidative stress, but in the course of experiment diploids expressed enhanced accumulation of compounds with higher antioxidative potential.
      PubDate: 2014-08-19T00:12:36.454616-05:
      DOI: 10.1111/php.12300
  • Design of a Gd‐DOTA‐phthalocyanine conjugate combining
           MRI‐contrast imaging and photosensitization properties as a
           potential molecular theranostic
    • Authors: Duygu Aydın Tekdaş; Ruslan Garifullin, Berna Şentürk, Yunus Zorlu, Umut Gundogdu, Ergin Atalar, Ayse B. Tekinay, Alexander A. Chernonosov, Yusuf Yerli, Fabienne Dumoulin, Mustafa O. Guler, Vefa Ahsen, Ayşe Gül Gürek
      Pages: n/a - n/a
      Abstract: The design and synthesis of a phthalocyanine ‐ Gd‐DOTA conjugate is presented to open the way to novel molecular theranostics, combining the properties of MRI contrast imaging with photodynamic therapy. The rational design of the conjugate integrates isomeric purity of the phthalocyanine core substitution, suitable biocompatibility with the use of polyoxo water‐solubilizing substituents, and a convergent synthetic strategy ended by the use of click chemistry to graft the Gd‐DOTA moiety to the phthalocyanine. Photophysical and photochemical properties, contrast imaging experiments and preliminary in vitro investigations proved that such a combination is relevant and lead to a new type of potential theranostic agent. This article is protected by copyright. All rights reserved.
      PubDate: 2014-08-16T01:52:30.89027-05:0
      DOI: 10.1111/php.12332
  • Photodynamic inactivation of bacterial and yeast biofilms with a cationic
    • Authors: Sandra Beirão; Sara Fernandes, Joel Coelho, Maria A. F. Faustino, João P. C. Tomé, Maria G. P. M. S. Neves, Augusto C. Tomé, Adelaide Almeida, Angela Cunha
      Pages: n/a - n/a
      Abstract: The efficiency of 5,10,15,20‐tetrakis(1‐methylpyridinium‐4‐yl)porphyrin tetra‐iodide (Tetra‐Py+‐Me) in the photodynamic inactivation of single‐species biofilms of Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans and mixed biofilms of S. aureus and C. albicans was evaluated. The effect on the extracellular matrix of P. aeruginosa was also assessed. Irradiation with white light up to an energy dose of 64.8 J cm‐2 in the presence of 20 μM of Tetra‐Py+‐Me Tetra‐Py+‐Me caused significant inactivation in all single‐species biofilms (3 ‐ 6 log reductions), although the susceptibility was attenuated in relation to planktonic cells. In mixed biofilms, the inactivation of S. aureus was as efficient as in single‐species biofilms but the susceptibility of C. albicans decreased. In P. aeruginosa biofilms, a reduction of 81% in the polysaccharides content of the matrix was observed after treatment with a 20 μM PS concentration and a total light dose of 64.8 J cm‐2. The results show that the Tetra‐Py+‐Me causes significant inactivation of the microorganisms, either in biofilms or in the planktonic form, and demonstrate that polysaccharides of the biofilm matrix may be a primary target of photodynamic damage. This article is protected by copyright. All rights reserved.
      PubDate: 2014-08-12T00:21:34.055195-05:
      DOI: 10.1111/php.12331
  • Proanthocyanidins from Grape Seeds Inhibit UV Radiation‐Induced
           Immune Suppression in Mice: Detection and Analysis of Molecular and
           Cellular Targets
    • Authors: Santosh K. Katiyar
      Pages: n/a - n/a
      Abstract: Ultraviolet (UV) radiation‐induced immunosuppression has been linked with the risk of skin carcinogenesis. Approximately, two million new cases of skin cancers, including melanoma and non‐melanoma, diagnosed each year in the USA and therefore have a tremendous bad impact on public health. Dietary phytochemicals are promising options for the development of effective strategy for the prevention of photodamaging effects of UV radiation including the risk of skin cancer. Grape seed proanthocyanidins (GSPs) are such phytochemicals. Dietary administration of GSPs with AIN76A control diet significantly inhibits UV‐induced skin tumor development as well as suppression of immune system. UV‐induced suppression of immune system is commonly determined using contact hypersensitivity (CHS) model which is a prototype of T cell‐mediated immune response. We present evidence that inhibition of UV‐induced suppression of immune system by GSPs is mediated through: (i) the alterations in immunoregulatory cytokines, interleukin (IL)‐10 and IL‐12, (ii) DNA repair, (iii) stimulation of effector T cells, and (iv) DNA repair‐dependent functional activation of dendritic cells in mouse model. These information have important implications for the use of GSPs as a dietary supplement in chemoprevention of UV‐induced immunosuppression as well as photocarcinogenesis. This article is protected by copyright. All rights reserved.
      PubDate: 2014-08-12T00:21:21.261632-05:
      DOI: 10.1111/php.12330
  • The effects of UV‐B radiation intensity on biochemical parameters
           and active ingredients in flowers of Qi chrysanthemum and Huai
    • Authors: Xiao‐Qin Yao; Jian‐Zhou Chu, Xue‐Li He, Chao Si
      Pages: n/a - n/a
      Abstract: The paper studied UV‐B‐effects on biochemical parameters and active ingredients in flowers of Qi chrysanthemum and Huai chrysanthemum during the bud stage. The experiment included four UV‐B radiation levels (CK, ambient UV‐B; T1, T2 and T3 indicated a 5%, 10% and 15% increase in ambient UV‐BBE, respectively) to determine the optimal UV‐B radiation intensity in regulating active ingredients level in flowers of two chrysanthemum varieties. Flower dry weight of two cultivars was not affected by UV‐B radiation under experimental conditions reported here. UV‐B treatments significantly increased the rate of superoxide radical production, hydrogen peroxide (H2O2) (except for T1) and malondialdehyde concentration in flowers of Huai chrysanthemum, and H2O2 concentration in flowers of Qi chrysanthemum. T2 and T3 treatments induced a significant increase in penylalanine ammonia lyase enzyme (PAL) activity, anthocyanins, proline, ascorbic acid, chlorogenic acid and flavone content in flowers of two chrysanthemum varieties, and there were no significant differences in PAL activity, ascorbic acid, flavone and chlorogenic acid content between the two treatments. These results indicated that appropriate UV‐B radiation intensity did not result in the decrease in flower yield, and could regulate PAL activity and increase active ingredients content in flowers of two chrysanthemum varieties. This article is protected by copyright. All rights reserved.
      PubDate: 2014-08-11T10:56:51.994649-05:
      DOI: 10.1111/php.12329
  • Directed improvement of Luciferin Regenerating Enzyme (LRE) binding
           properties: Implication of some conserved residues in luciferin binding
    • Authors: Roohullah Hemmati; Reza H. Sajedi, Nuredin Bakhtiari, Saman Hosseinkhani
      Pages: n/a - n/a
      Abstract: Luciferin regenerating enzyme (LRE) contributes to in vitro recycling of D‐luciferin to produce persistent and longer light emission by luciferase. Luciferin binding domains I and II among LREs regarded as potential candidates for luciferin‐binding sites. In this study, for the first time, amino acids T69, G75 and K77 located at luciferin binding domain I of LRE from L. turkestanicus (T‐LRE) substituted by using site‐directed mutagenesis. Single mutant T69R increased luciferase light output more than 2‐fold over a longer time in comparison with a wild‐type and other mutants of T‐LRE. Nevertheless, double mutant (K77E/T69R) increased the amount of bioluminescent signal more than 2‐fold over a short time. In addition, G75E, K77E and G75E/T69R mutants didn't improve luciferin‐luciferase in vitro bioluminescence. Based on our results, addition of K77E/G75E and K77E/G75E/T69R mutants caused intermediate changes in bioluminescence from in vitro luciferin‐luciferase reaction. These findings indicated that the amino acids in question are possible to be located within T‐LRE active site. It may also be suggested that substituted Arg69 (Arg218) plays an important role in luciferin binding and the existence of Gly75 as well as Lys77 is essential for T‐LRE which has already evolved to have different functions in nature. This article is protected by copyright. All rights reserved.
      PubDate: 2014-08-08T01:36:32.477959-05:
      DOI: 10.1111/php.12328
  • A New Series of Fluorescent Indicators for Super Acids
    • Authors: I‐Chih Shih; Yu‐Shan Yeh, I‐Che Wu, You‐Hua Chen, Jiun‐Yi Shen, Yi‐An Chen, Mei‐Lin Ho, Pi‐Tai Chou
      Pages: n/a - n/a
      Abstract: The photophysical properties of fluorescent Hammett acidity indicator derived from 3,4,5,6‐tetrahydrobis(pyrido[3,2‐g]indolo)[2,3‐a:3’,2’‐j]acridine (1a), 6‐bis(pyrido[3,2‐g]indol‐2’‐yl)pyridine (1b) and their analogues have been investigated in sulfuric acid solutions by means of absorption, fluorimetry, relaxation dynamics and computational approach. These new indicators undergo a reversible protonation process in the Hammett acidity range of H0 < 0, accompanied by a drastic increase of the bright blue‐green (1a) or yellow (1b) fluorescence intensity upon increasing the acidity. For 1a in H2SO4, the emission yield increases as large as 200 folds from pH = ‐0.41 to the Hammett acidity range of ‐5.17, the results of which are rationalized by a much increase of the steric hindrance upon third protonation toward the central pyridinic site, together with their accompanied changes of electronic configuration from charge transfer to a delocalized ππ* character in the lowest lying excited state. The combination of 1a and 1b renders a wide and linear range of H0 measurement from ‐1.2 to ‐5.1 detected by highly intensive fluorescence. This article is protected by copyright. All rights reserved.
      PubDate: 2014-08-07T02:09:17.116293-05:
      DOI: 10.1111/php.12326
  • Self‐aggregation of synthetic zinc chlorophyll derivatives
           possessing 31‐hydroxy or methoxy group and 131‐mono‐ or
           dicyanomethylene moiety in non‐polar organic solvents as models of
           chlorosomal bacteriochlorophyll‐d aggregates
    • Authors: Hitoshi Tamiaki; Masaki Kuno, Masaki Ohata
      Pages: n/a - n/a
      Abstract: Methyl 131‐(di)cyanomethylene‐pyropheophorbides were synthesized by Knoevenagel reactions of the corresponding 131‐oxo‐chlorins prepared from modifying chlorophyll‐a with malononitrile or cyanoacetic acid. Alternatively, methyl 131‐cyanomethylene‐pyropheophorbides were produced by Wittig reactions of 131‐oxo‐chlorins with Ph3P=CHCN. Self‐aggregation of zinc complexes of the semi‐synthetic chlorophyll derivatives possessing a hydroxy or methoxy group at the 31‐position was examined in 1%(v/v) tetrahydrofuran or dichloromethane and hexane by electronic absorption and circular dichroism spectroscopy. Although intermolecular hydrogen‐bonding between the 31‐hydroxy and 131‐oxo groups of bacteriochlorophylls‐c/d/e/f was essential for their self‐aggregation in natural light‐harvesting antenna systems (= chlorosomes), zinc 31‐hydroxy‐131‐di/monocyanomethylene‐chlorins self‐aggregated in the less/lesser polar organic solvents to form chlorosome‐like large oligomers in spite of lacking the 131‐oxo moiety as the hydrogen‐bonding acceptor. Zinc 31‐methoxy‐131‐dicyanomethylene‐chlorin gave similar self‐aggregates regardless of lack of both the 31‐hydroxy and 131‐oxo groups. The present self‐aggregation was ascribable to stronger coordination of the 31‐oxygen atom to the central zinc than the conventional systems, where the electron‐withdrawing cyano group(s) increased the coordinative ability of the central zinc through chlorin π‐system. This article is protected by copyright. All rights reserved.
      PubDate: 2014-08-06T10:35:26.842727-05:
      DOI: 10.1111/php.12327
  • Hydroxyl Radical as an unlikely Key Intermediate in the Photodegradation
           of Emerging Pollutants
    • Authors: Gemma M. Rodriguez‐Muñiz; Juan Gomis, Antonio Arques, Ana M. Amat, M. Luisa Marin, Miguel A. Miranda
      Pages: n/a - n/a
      Abstract: In this work a kinetic model, in combination with time‐resolved experiments, is applied to assess the involvement of •OH in the photodegradation of emerging pollutants (EPs) by means of advanced oxidation processes. By contrast with the general assumption, quenching of the short‐lived •OH in the real waters by the (highly diluted) EPs must be very inefficient, so removal of EPs cannot purely rely on the generation and reaction of •OH. This suggests that more complex pathways have to be considered to explain the photodegradation of EPs actually achieved under the employed oxidative conditions, possibly involving other reactive species with longer lifetimes or chain degradation processes. This article is protected by copyright. All rights reserved.
      PubDate: 2014-07-28T03:59:40.0529-05:00
      DOI: 10.1111/php.12325
  • Rapid sonosynthesis of N‐doped nano TiO2 on wool fabric at low
           temperature: Introducing Self‐cleaning, Hydrophilicity,
           Antibacterial/Antifungal Properties with low Alkali Solubility, Yellowness
           and Cytotoxicity
    • Authors: Amir Behzadnia; Majid Montazer, Abousaeid Rashidi, Mahnaz Mahmoudi Rad
      Pages: n/a - n/a
      Abstract: Nano nitrogen‐doped titanium dioxide were rapidly prepared by hydrolysis of titanium isopropoxide at 75‐80 °C using in situ sonochemical synthesis by introducing ammonia. Various concentrations of titanium isopropoxide were examined to deposit nano nitrogen‐doped titanium dioxide through impregnation of the wool fabric in ultrasound bath followed by curing. The antibacterial/antifungal activities of wool samples were assessed against two common pathogenic bacteria including Escherichia coli and Staphylococcus aureus and the diploid fungus Candida albicans. The sonotreated wool fabrics indicated no adverse effects on human dermal fibroblasts. The presence of nano‐particles on the sonotreated wool fabrics were confirmed by FE‐SEM images and EDS patterns and X‐ray mapping and the crystalline size of nano‐particles were estimated through XRD results. The role of both pH and precursor concentration on the various properties of the fabric was investigated and the optimized conditions introduced using response surface methodology. This article is protected by copyright. All rights reserved.
      PubDate: 2014-07-28T03:59:39.080091-05:
      DOI: 10.1111/php.12324
  • Hypericin Damages the Ectatic Capillaries in a Roman Cockscomb Model and
           Inhibits the Growth of Human Endothelial Cells More Potently Than
           Hematoporphyrin Does Through Induction of Apoptosis
    • Authors: Zhuo‐heng Li; De‐sheng Meng, Yuan‐yuan Li, Lai‐chun Lu, Cai‐ping Yu, Qian Zhang, Hai‐yan Guan, Chen‐wen Li, Xue Yang, Ruo‐qiu Fu
      Pages: n/a - n/a
      Abstract: Hypericin (HY) is a promising photosensitizer (PS) for use in photodynamic therapy (PDT). Port‐wine stains (PWSs) are congenital superficial dermal capillary malformations. In this study, we evaluated the photocytotoxic effects of HY for PDT in human vascular endothelial cells and a chicken cockscomb model. HY significantly inhibited the growth of human umbilical vein endothelial cells (HUVECs), as determined by colorimetric assays and morphological observation, and flow cytometry assays indicated induction of apoptosis and collapse of the mitochondrial membrane potential. In addition, HY more effectively inhibited growth of and induced apoptosis in HUVECs compared with hematoporphyrin (HP). Further experiments performed in a Roman chicken cockscomb model also showed a clear photocytotoxic effect on the cockscomb dermal capillary upon intravenous injection of HY. This effect may be due to the role of HY in the induction of apoptosis. Transmission electron microscopical analysis showed mitochondrial morphological changes such as incomplete ridges and swelling, and immunohistochemical assays showed an increase in the release of cytochrome c. In conclusion, HY exhibited a greater photocytotoxic activity than did HP toward the growth of endothelial cells and may thus represent a potent PS for PWS PDT. This article is protected by copyright. All rights reserved.
      PubDate: 2014-07-26T02:42:55.177775-05:
      DOI: 10.1111/php.12323
  • ROS and p53 in Regulation of UVB‐induced HDM2 Alternative Splicing
    • Authors: Lingying Tong; Shiyong Wu
      Pages: n/a - n/a
      Abstract: Alternative splicing plays an important role in proteasome diversity and gene expression regulation in eukaryotic cells. Hdm2, the human homolog of mdm2 (murine double minute oncogene 2), is known to be an oncogene as its role in suppression of p53. Hdm2 alternative splicing, occurs in both tumor and normal tissues, is believed to be a response of cells for cellular stress, and thus modulate p53 activity. Therefore, understanding the regulation of hdm2 splicing is critical in elucidating the mechanisms of tumor development and progression. In this study, we determined the effect of ultraviolet B light (UVB) on alternative splicing of hdm2. Our data indicated that UVB (50 mJ cm−2) alone is not a good inducer of alternative splicing of hdm2. The less effectiveness could be due to the induction of ROS and p53 by UVB because removing ROS by L‐NAC (10 mm) in p53 null cells could lead to alternative splicing of hdm2 upon UVB irradiation. Hdm2, the human homologue of mdm2 (murine double minute oncogene 2), is an oncogene for its role in suppression of p53. Hdm2 alternative splicing, occurs in both tumor and normal tissues, is suggested to be a response of cells for cellular stress, and thus modulate p53 activity. In this study, we demonstrated that UVB is weaker inducer of alternative splicing than UVC is. We also provided evidences that the UV‐induced alternative splicing is promoted by DNA‐damage, but suppressed by ROS formation and p53 activity of the irradiated cells.
      PubDate: 2014-07-26T00:02:01.70935-05:0
      DOI: 10.1111/php.12306
  • UVB Irradiation Enhances TiO2 Nanoparticle‐induced Disruption of
           Calcium Homeostasis in Human Lens Epithelial Cells
    • Authors: Qiuxin Wu; Dadong Guo, Yuxiang Du, Dongmei Liu, Daoguang Wang, Hongsheng Bi
      Pages: n/a - n/a
      Abstract: Currently, titanium dioxide nanoparticles (TiO2 NPs) have been widely used in various applications including cosmetics, food additives and biomedicine. However, there are few reports available using TiO2 NPs to treat ocular diseases. Posterior capsular opacification (PCO) is the most frequent complication after cataract surgery, which is induced by the proliferation and migration of lens epithelial cells. Thus, inhibiting the proliferation of lens epithelial cells will efficiently reduce the occurrence of PCO. In this study, we investigated the effects of TiO2 NPs on HLE B‐3 cells with or without ultraviolet B (UVB) irradiation in vitro. We found that TiO2 NPs can inhibit HLE B‐3 cell growth, cause the elevation of intracellular [Ca2+], produce excessive reactive oxygen species (ROS), further reduce Ca2+‐ATPase activity and decrease the expression of plasma membrane calcium ATPase 1 (PMCA1), finally disrupt the intracellular calcium homeostasis and induce cell damage. Importantly, UVB irradiation can apparently enhance these effects on HLE B‐3 cells in the presence of TiO2 NPs. Taken together, the generation of excessive ROS and the disruption of intracellular calcium homeostasis may be both involved in TiO2 nanoparticle‐induced HLE B‐3 cell damage under UVB irradiation. This article is protected by copyright. All rights reserved.
      PubDate: 2014-07-24T11:09:55.145055-05:
      DOI: 10.1111/php.12322
  • Photooxidation of Tryptophan Leading to 2‐Aminoacetophenone ‐
           A Possible Reason for the Untypical Aging Off‐flavor in Wine
    • Authors: Nora Horlacher; Wolfgang Schwack
      Pages: n/a - n/a
      Abstract: 2‐Aminoacetophenone (AAP) was recognized as the key compound for the so‐called untypical aging off‐flavor (UTA) in Vitis vinifera wines. In this study, it was shown that AAP can be formed by photooxidation of free and protein‐bound tryptophan (TRP) in combination with a subsequent storage in model wine. Solutions of TRP and lysozyme were exposed to artificial sunlight both in the presence and in the absence of the photosensitizer riboflavin. Aliquots of the irradiation batches were stored in model wine solutions containing tartaric acid, sulfite, and ethanol in different combinations. AAP formation could be identified from both free and bound (lysozyme) TRP, while free TRP resulted in higher yields. The presence of riboflavin during irradiation generally favored the AAP formation. AAP formation increased with increasing irradiation times, but AAP was not detectable, if TRP was directly incubated in model wine. Not only the irradiation time but also the storage time of model wines favored the formation of AAP. Concerning the model wine composition, it became evident that the presence of tartaric acid resulted in the highest AAP formation during storage. This article is protected by copyright. All rights reserved.
      PubDate: 2014-07-22T01:48:41.844654-05:
      DOI: 10.1111/php.12321
  • Validation and application of a model of oxygen consumption and diffusion
           during photodynamic therapy in vitro
    • Authors: Mark A. Weston; Michael S. Patterson
      Pages: n/a - n/a
      Abstract: The photophysical parameters for the photosensitizer Pd(II) meso‐Tetra(4‐carboxyphenyl) porphine (PdT790) acquired in a previous study were incorporated into the PDT oxygen diffusion models for cell suspensions and cell monolayers. The time dependent phosphorescence signals generated by the diffusion models are shown to match signals previously measured by Weston and Patterson when reasonable physical and photophysical parameters are used. Simulations were performed to investigate the effects of metabolic and photodynamic oxygen consumption rates on the PDT dose in each of the treatment geometries. It was found that in cell suspensions of less than 1 million cells per mL, PDT should not be inhibited by hypoxia if the photodynamic consumption rate is less than 1 mM s−1. For cell monolayers the optimal photodynamic oxygen consumption rate was found to depend on the metabolic rate of oxygen consumption. If cells remained well oxygenated in the absence of PDT, then maximum PDT dose was delivered with the lowest practical photodynamic oxygen consumption rate. Simulations of PDT treatments for multicell tumor spheroids showed that large anoxic cores develop within the spheroids and, as a consequence, less PDT dose is delivered in comparison to similar treatments in cell suspensions and cell monolayers. This article is protected by copyright. All rights reserved.
      PubDate: 2014-07-21T01:28:08.557303-05:
      DOI: 10.1111/php.12320
  • Enhanced Light‐Harvesting Capacity by Micellar Assembly of Free
           Accessory Chromophores and LH1‐like Antennas
    • Authors: Michelle A. Harris; Tuba Sahin, Jianbing Jiang, Pothiappan Vairaprakash, Pamela S. Parkes‐Loach, Dariusz M. Niedzwiedzki, Christine Kirmaier, Paul A. Loach, David F. Bocian, Dewey Holten, Jonathan S. Lindsey
      Pages: n/a - n/a
      Abstract: Biohybrid light‐harvesting antennas are an emerging platform technology with versatile tailorability for solar‐energy conversion. These systems combine the proven peptide scaffold unit utilized for light harvesting by purple photosynthetic bacteria with attached synthetic chromophores to extend solar coverage beyond that of the natural systems. Herein, synthetic unattached chromophores are employed that partition into the organized milieu (e.g., detergent micelles) that house the LH1‐like biohybrid architectures. The synthetic chromophores include a hydrophobic boron‐dipyrrin dye (A1) and an amphiphilic bacteriochlorin (A2), which transfer energy with reasonable efficiency to the bacteriochlorophyll acceptor array (B875) of the LH1‐like cyclic oligomers. The energy‐transfer efficiencies are markedly increased upon covalent attachment of a bacteriochlorin (B1 or B2) to the peptide scaffold, where the latter likely acts as an energy‐transfer relay site for the (potentially diffusing) free chromophores. The efficiencies are consistent with a Förster (through‐space) mechanism for energy transfer. The overall energy‐transfer efficiency from the free chromophores via the relay to the target site can approach those obtained previously by relay‐assisted energy transfer from chromophores attached at distant sites on the peptides. Thus, the use of free accessory chromophores affords a simple design to enhance the overall light‐harvesting capacity of biohybrid LH1‐like architectures. This article is protected by copyright. All rights reserved.
      PubDate: 2014-07-21T01:28:02.651894-05:
      DOI: 10.1111/php.12319
  • Effect of Immunosuppressants Tacrolimus and Mycophenolate Mofetil on the
           Keratinocyte UVB Response
    • Authors: Mei Ming; Baozhong Zhao, Lei Qiang, Yu‐Ying He
      Pages: n/a - n/a
      Abstract: Non‐melanoma skin cancer, derived from epidermal keratinocytes, is the most common malignancy in organ transplant recipients, causes serious morbidity and mortality, and is strongly associated with solar ultraviolet (UV) exposure. Preventing and treating skin cancer in these individuals has been extraordinarily challenging. Following organ transplantation, the immunosuppressants are used to prevent graft rejection. Until now, immunosuppression has been assumed to be the major factor leading to skin cancer in this setting. However, the mechanism of skin carcinogenesis in organ transplant recipients has not been understood to date; specifically, it remains unknown whether these cancers are immunosuppression‐dependent or ‐independent. In particular, it remains poorly understood what is the mechanistic carcinogenic action of the newer generation of immunosuppressants including tacrolimus and mycophenolate mofetil (MMF). Here we show that tacrolimus and MMF impairs UVB‐induced DNA damage repair and apoptosis in human epidermal keratinocytes. In addition, tacrolimus inhibits UVB‐induced checkpoint signaling. However, MMF had no effect. Our findings have demonstrated that tacrolimus and MMF compromises proper UVB response in keratinocytes, suggesting an immunosuppression‐independent mechanism in the tumor‐promoting action of these immunosuppressants. This article is protected by copyright. All rights reserved.
      PubDate: 2014-07-21T01:27:27.76301-05:0
      DOI: 10.1111/php.12318
  • In Vitro Investigations on the Effect of Dermal Fibroblasts on
           Keratinocyte Responses to Ultraviolet B Radiation
    • Authors: Tara L Fernandez; Derek R Van Lonkhuyzen, Rebecca A Dawson, Michael G Kimlin, Zee Upton
      Pages: n/a - n/a
      Abstract: Exposure to ultraviolet radiation (UVR) is closely linked to the development of skin cancers in humans. The ultraviolet B (UVB) radiation wavelength (280‐320 nm), in particular, causes DNA damage in epidermal keratinocytes, which are linked to the generation of signature pre‐malignant mutations. Interactions between dermal fibroblasts and keratinocytes play a role in epidermal repair and regeneration after UVB‐induced damage. To investigate these processes, established two and three‐dimensional culture models were utilised to study the impact of fibroblast‐keratinocyte crosstalk during the acute UVB response. Using a co‐culture system it was observed that fibroblasts enhanced keratinocyte survival and the repair of cyclobutane pyrimidine dimers (CPDs) after UVB radiation exposure. These findings were also mirrored in irradiated human skin co‐culture models employed in this study. Fibroblast co‐culture was shown to play a role in the expression and activation of members of the apoptotic cascade, including caspase‐3 and Bad. Interestingly, the expression and phosphorylation of p53, a key player in the regulation of keratinocyte cell fate post‐irradiation, was also shown to be influenced by fibroblast‐produced factors. This study highlights the importance of synergistic interactions between fibroblasts and keratinocytes in maintaining a functional epidermis while promoting repair and regeneration following UVB radiation‐induced damage. This article is protected by copyright. All rights reserved.
      PubDate: 2014-07-18T03:00:24.137746-05:
      DOI: 10.1111/php.12317
  • Red‐Light interferes in UVA‐induced Photoaging of Human Skin
           fibroblast Cells
    • Authors: Tianhui Niu; Yan Tian, Qu Ren, Lizhao Wei, Xiaoxin Li, Qing Cai
      Pages: n/a - n/a
      Abstract: The possible regulation mechanism of red light was determined to discover how to retard UVA‐induced skin photoaging. Human skin fibroblasts were cultured and irradiated with different doses of UVA, thus creating a photoaging model. Fibroblasts were also exposed to a sub‐toxic dose of UVA combined with a red light‐emitting diode (LED) for 5 continuous days. Three groups were examined: control, UVA and UVA plus red light. Cumulative exposure doses of UVA were 25 J/cm2, and the total doses of red light were 0.18 J/cm2. Various indicators were measured before and after irradiation, including cell morphology, viability, β‐galactosidase staining, apoptosis, cycle phase, the length of telomeres and the protein levels of photoaging‐related genes. Red light irradiation retarded the cumulative low‐dose UVA irradiation‐induced skin photoaging, decreased the expression of senescence‐associated β‐galactosidase, up‐regulated SIRT1 expression, decreased matrix metalloproteinase MMP‐1 and the acetylation of p53 expression, reduced the horizon of cell apoptosis, and enhanced cell viability. Furthermore, the telomeres in UVA‐treated cells were shortened compared to those of cells in the red light groups. These results suggest that red light plays a key role in the anti‐photoaging of human skin fibroblasts by acting on different signaling transduction pathways. This article is protected by copyright. All rights reserved.
      PubDate: 2014-07-12T06:29:10.737088-05:
      DOI: 10.1111/php.12316
  • The injury and cumulative effects on human skin by UV exposure from
           artificial fluorescence emission
    • Authors: Yan. Tian; Wei. Liu, TianHui. Niu, CaiHong. Dai, Xiaoxin. Li, Caijuan. Cui, Xinyan. Zhao, Yaping. E, Hui. Lu
      Pages: n/a - n/a
      Abstract: The injury and cumulative effects of UV emission from fluorescence lamp were studied. UV intensity from fluorescence lamp was measured, and human skin samples (hips, 10 volunteers) were exposed to low dose UV irradiation (three times per week for 13 consecutive weeks). Three groups were examined: control group without UV radiation; low dose group with a cumulative dose of 50 J/cm2 which was equivalent to irradiation of the face during indoor work for 1.5 years; and high dose group with 1000 J/cm2 cumulative dose equivalent to irradiation of the face during outdoor activities for 1 year. Specific indicators were measured before and after UVA irradiation. The findings showed that extending the low dose UVA exposure decreased the skin moisture content and increased the transepidermal water loss as well as induced skin colour changes (decreased L* value, increased M index). Furthermore, irradiated skin showed an increased thickness of cuticle and epidermis, skin oedema, light colour and unclear staining collagen fibres in the dermis, and elastic fibre fragmentation. In addition, MMP‐1, p53 and SIRT1 expression was also increased. Long‐term exposure of low dose UVA radiation enhanced skin photoageing.The safety of the fluorescent lamp needs our attention. This article is protected by copyright. All rights reserved.
      PubDate: 2014-07-11T01:39:39.948528-05:
      DOI: 10.1111/php.12315
  • Study of the Photodegradation Kinetics and Pathways of Hexaflumuron in
           Liquid Media
    • Authors: Lu Chengying; Xing Yin, Xiaofeng Liu, Minghua Wang
      Pages: n/a - n/a
      Abstract: Hexaflumuron, one of the benzoylphenylurea insect growth regulators, can be leached into surface water and thus having a potential impact on aquatic organisms In this study, the photodegradation processes of hexaflumuron under high‐pressure mercury lamp irradiation were assessed. The photodegradation kinetics were studied, as were the effects of pH,different light sources, organic solvents and environmental substances, including nitrate ions (NO3−), nitrite ions (NO2−), ferrous ions (Fe2+), ferric ions (Fe3+), humic acid, sodium dodecyl sulfate (SDS) and hydrogen peroxide (H2O2). Three photodegradation products in methanol were identified by gas chromatography‐mass spectrometry (GC‐MS). In general, the degradation of hexaflumuron followed first‐order kinetics. In the four media studied, the photodegradation rate order was n‐hexane > methanol > ultrapure water > acetone. Faster degradation was observed under high‐pressure mercury lamp irradiation than under xenon lamp irradiation. The pH had a considerable effect, with the most rapid degradation occurring at pH 5.0. The photodegradation rate of hexaflumuron was promoted in the presence of NO3−, NO2−, Fe2+, humic acid, SDS and H2O2 but inhibited by Fe3+. Moreover, the presumed photodegradation pathway was proposed to be the cleavage of the urea linkage. This article is protected by copyright. All rights reserved.
      PubDate: 2014-07-11T01:39:36.74197-05:0
      DOI: 10.1111/php.12314
  • Observation of in vivo morphologic changes after carbon dioxide ablative
           fractional laser in a mouse model using non‐invasive imaging
           modalities and comparison with histologic examination
    • Authors: Kwang Ho Yoo; Tae Rin Kwon, So Young Kim, Yi Seop Song, Young Sook Cheon, Yu Mi Kim, In Kwon Yeo, Eun Jung Ko, Kapsok Li, Myeung Nam Kim, Beom Joon Kim
      Pages: n/a - n/a
      Abstract: Ablative fractional carbon dioxide (CO2) lasers have been widely used for several types of cosmetic dermatosis. A number of previous studies have evaluated this technique in animals or human beings by observing morphologic changes using an invasive modality such as skin biopsy. In this study, we assessed in vivo skin changes after CO2 ablative fractional laser treatment in a mouse model using non‐invasive imaging modalities (Folliscope® and Visioscan 98®), and each results was compared with data from histologic examination. An ablative fractional CO2 laser was applied with different pulse energy between 7 to 35 mJ/microspot. As results of above methods, we also confirmed that the CO2 ablative fractional laser generated injuries with increasing width and depth with increasing pulse energy. Although numerous papers have described application of this laser in vivo skin specimens, our study evaluated the feasibility of using relative non‐invasive imaging modalities for assessing the outcome of laser ablation. Based on our data, we suggest that these technologies may be useful alternative modalities for assessing laser ablation that are easier to perform and less invasive than skin biopsy. This article is protected by copyright. All rights reserved.
      PubDate: 2014-07-11T01:39:34.393127-05:
      DOI: 10.1111/php.12313
  • Sun‐protection Provided by Regulation School Uniforms in Australian
           Schools: An Opportunity to Improve Personal Sun‐protection During
    • Authors: Denise Turner; Simone Lee Harrison
      Pages: n/a - n/a
      Abstract: Childhood sun‐exposure is linked to excessive pigmented mole development and melanoma risk. Clothing provides a physical barrier, protecting skin from ultraviolet radiation (UVR). Extending sleeves to elbow‐length and shorts to knee‐length has been shown to significantly reduce mole acquisition in pre‐schoolers from tropical Queensland. We used publicly‐available uniform images and guidelines from primary schools in Townsville (latitude 19.25°S, n=43 schools), Cairns (16.87°S, n=46), and the Atherton Tablelands (17.26°S, n=23) in tropical Australia to objectively determine the body surface proportion covered by regulation school uniforms. Uniforms of non‐government, large (≥800 students), urban, educationally‐advantaged schools with comprehensive sun‐protection policies covered more skin than those of government schools (63.2% Vs 62.0%; p
      PubDate: 2014-07-09T11:57:44.861834-05:
      DOI: 10.1111/php.12312
  • Chemical and Biological Mechanisms of Pathogen Reduction Technologies
    • Authors: Janna M. Mundt; Lindsay Rouse, Jeroen den Bossche, Raymond P. Goodrich
      Pages: n/a - n/a
      Abstract: Within the last decade new technologies have been developed and implemented which employ light, often in the presence of a photosensitizer, to inactivate pathogens that reside in human blood products for the purpose of transfusion. These pathogen reduction technologies attempt to find the proper balance between pathogen kill and cell quality. Each system utilizes various chemistries that not only impact which pathogens they can inactivate and how, but also how the treatments affect the plasma and cellular proteins and to what degree. This paper aims to present the various chemical mechanisms for pathogen reduction in transfusion medicine that are currently practiced or in development. This article is protected by copyright. All rights reserved.
      PubDate: 2014-07-06T23:55:02.76603-05:0
      DOI: 10.1111/php.12311
  • Cellular Changes Associated with the Acclimation of the Intertidal Sea
           Anemone Actinia tenebrosa to Ultraviolet Radiation.
    • Authors: Victor Mauricio Cubillos; Miles D. Lamare, Barrie M. Peake, David J. Burritt
      Pages: n/a - n/a
      Abstract: To assess the relative importance of long‐ and short‐term cellular defence mechanisms in seasonally UV‐R acclimated Actinia tenebrosa (Anthozoa, Actiniidae), individuals were exposed to summer doses of PAR, UV‐A, UV‐B and enhanced UV‐B (20%) for a period of 4 days. Mycosporine‐like amino acids (MAAs) and cyclobutane pyrimidine dimer (CPD) concentrations were quantified, while oxidative damage to lipids and proteins, and the activities/levels of the antioxidant enzymes SOD, CAT, GR, GPOX and total glutathione were determined. Our results show that summer UV‐R acclimated individuals had a higher UV‐R tolerance, with no significant increases in CPDs levels, than winter acclimated sea anemones possibly due to higher MAA concentrations. Summer acclimated individuals showed increased lipid and protein oxidation and GPOX activity only when they were exposed to UV‐B at 20% above ambient UV‐R levels. In contrast, winter acclimated sea anemones showed elevated levels of oxidative damage, GPOX and SOD activities after exposure to UV‐A or UV‐B at ambient and elevated levels. Thus, this study indicates that long‐term UV‐R acclimation mechanisms such as the accumulation of MAAs could be more important than short term increases in antioxidant defences with respect to reducing indirect UV‐R damage in intertidal sea anemones. This article is protected by copyright. All rights reserved.
      PubDate: 2014-07-05T10:29:03.403438-05:
      DOI: 10.1111/php.12310
  • Disinfection Of Escherichia Coli Gram Negative Bacteria Using Surface
           Modified TiO2: Optimization Of Ag Metallization And Depiction Of Charge
           Transfer Mechanism
    • Authors: L. Gomathi Devi; Nagaraj B
      Pages: n/a - n/a
      Abstract: The antibacterial activity of silver deposited TiO2 (Ag‐TiO2) against Gram negative Escherichia coli bacteria was investigated by varying the Ag metal content from 0.10% ‐ 0.50% on the surface of TiO2. Ag depositions by photoreduction method were found to be stable. Surface silver metallization was confirmed by EDAX and XPS studies. Photoluminescence studies shows that charge carrier recombination is less for 0.1% Ag‐TiO2 and this catalyst shows superior bactericidal activity under solar light irradiation compared to Sol gel TiO2 (SG‐TiO2) due to the surface plasmon effect. The energy levels of deposited Ag are dependent on the Ag content and it varies from ‐4.64 eV to ‐1.30 eV with respect to vacuum energy level based on atomic silver to bulk silver deposits. The ability of electron transfer from Ag deposit to O2 depends on the position of the energy levels. 0.25% and 0.50% Ag depositions showed detrimental effect on bactericidal activity due to the mismatch of energy levels. The effect of the EROS (External generation of the Reactive Oxygen Species by 0.1% Ag‐TiO2) and IROS (Interior generation of Reactive Oxygen Species within the bacteria) on the bactericidal inactivation is discussed in detail. This article is protected by copyright. All rights reserved.
      PubDate: 2014-07-03T09:48:25.04107-05:0
      DOI: 10.1111/php.12308
  • Photoactive hybrid materials of lanthanide (Eu3+, Tb3+, Sm3+)
           beta‐diketonates and polymer resin through ionic liquid bridge
    • Authors: Ying Mei; Bing Yan
      Pages: n/a - n/a
      Abstract: A special multifunctional ionic liquid compound (1‐methyl‐3‐(2‐(thiocarboxyoxy)‐ethyl)‐2H‐imidazole‐1,3‐diium bromide (SHIL)) is used as the chemical bridge to link lanthanide beta‐diketonates and polymer resin, which are designated as Ln(L)4‐SHIL‐WR/MR (Ln = Eu, Tb, Sm; L= thenoyltrifluoroacetonate (TTA), acetylacetonate (AA), dibenzoylmethane (DBM); WR = Wang resin, MR = Merrifield resin). Among SHIL and polymer resin are assembled to form covalently bonded system through condensation reaction. Then tetrakis lanthanide beta‐diketonates are linked to SHIL through ion exchange reaction. Physical characterization and especially the photoluminescent performance of the multi‐component hybrids are studied. The hybrid materials possess good stability and excellent luminescent property. The results provide useful path to obtain luminescent hybrids for further practical application. This article is protected by copyright. All rights reserved.
      PubDate: 2014-07-02T00:20:22.559681-05:
      DOI: 10.1111/php.12307
  • Retarded Photooxidation of Cyamemazine in Biomimetic Microenvironments
    • Authors: Daniel Limones-Herrero; Raúl Pérez-Ruiz, M. Consuelo Jiménez, Miguel A. Miranda
      Pages: n/a - n/a
      Abstract: Cyamemazine (CMZ) is a neuroleptic drug that mediates cutaneous phototoxicity in humans. Here, the photobehavior of CMZ has been examined within α1-acid glycoproteins, β- and γ-cyclodextrins and SDS micelles. In all these microenvironments, CMZ emission was enhanced and blue-shifted, and its lifetime was longer. Irradiation of the entrapped drug at 355 nm, under air; led to the N,S-dioxide. Within glycoproteins or SDS micelles the reaction was clearly slower than in phosphate buffered solution (PBS); protection by cyclodextrins was less marked. Transient absorption spectroscopy in PBS revealed formation of the triplet state (3CMZ*) and the radical cation (CMZ+•). Upon addition of glycoprotein, the contribution of CMZ+• became negligible, whereas 3CMZ* dominated the spectra; in addition, the triplet lifetime became considerably longer. In cyclodextrins, this occurred to a lower extent. In all microheterogeneous systems, quenching by oxygen was slower than in solution; this was most remarkable inside glycoproteins. The highest protection from photooxidation was achieved inside SDS micelles. The results are consistent with photooxidation of CMZ through photoionization and subsequent trapping of the resulting radical cation by oxygen. This reaction is extremely sensitive to the medium and constitutes an appropriate probe for localization of the drug within a variety of biological compartments. This article is protected by copyright. All rights reserved.
      PubDate: 2014-06-20T22:47:16.822253-05:
      DOI: 10.1111/php.12303
  • Xeroderma Pigmentosum in the United Kingdom;
    • Authors: Alan R Lehmann
      Abstract: The seminal discovery by James Cleaver of defective DNA repair in xeroderma pigmentosum (XP) opened up an ever‐expanding field of DNA repair‐related disorders. In addition it put XP on the map and has led to improved diagnosis, care and management of affected patients. In the UK, we recently established a multi‐disciplinary specialist clinic for XP patients. All XP patients in the UK are able to visit the clinic where they are examined and advised by a team of specialists with detailed knowledge of the different aspects of XP. This article is protected by copyright. All rights reserved.
      PubDate: 2014-06-19T01:55:47.802274-05:
      DOI: 10.1111/php.12301
  • The Photolytic Activity of Poly‐Arginine Cell Penetrating Peptides
           Conjugated to Carboxy‐tetramethylrhodamine is Modulated by Arginine
           Residue Content and Fluorophore Conjugation Site
    • Authors: Nandhini Muthukrishnan; Stephen Donovan, Jean‐Philippe Pellois
      Pages: n/a - n/a
      Abstract: Upon light irradiation, Fluorophore–cell‐penetrating peptide (Fl‐CPP) conjugates can disrupt the integrity of biological membranes. This activity can in turn be used to photoinduce the disruption of endocytic organelles and promote the delivery of entrapped macromolecules such as proteins or RNAs into live cells. Recent mechanistic studies have shown that ROS production by the fluorophore and a latent lytic ability of CPPs act in synergy to elicit photolysis. However, how the structure of fluorophore‐CPP conjugates impacts this synergistic activity remains unclear. Herein, using red blood cells (RBCs) as a model of biological membranes, we show that the number of arginine residues in a CPP as well as the position of fluorophore with respect to the CPP dramatically affect the photolytic activity of a fluorophore‐CPP conjugate. These factors should therefore be considered for the development of effective photoinducible delivery agents. Fluorophore–cell‐penetrating peptide (Fl‐CPP) conjugates can disrupt membranes of endocytic organelles upon light irradiation and promote the delivery of entrapped macromolecules such as proteins or nucleic acids into a cells’ cytosol. ROS production by the fluorophore and a latent lytic ability of CPPs act in synergy to elicit photolysis. In this report, using red blood cells as a model of biological membranes, we show that the number of arginine residues in a CPP as well as the position of fluorophore with respect to the CPP dramatically affect the photolytic activity of a fluorophore–CPP conjugate. These factors should therefore be considered for the development of effective photoinducible delivery agents.
      PubDate: 2014-06-03T02:28:50.442713-05:
      DOI: 10.1111/php.12288
  • Combination of Oral Vitamin D3 with Photodynamic Therapy Enhances Tumor
           Cell Death in a Murine Model of Cutaneous Squamous Cell Carcinoma
    • Authors: Sanjay Anand; Kishore R. Rollakanti, Ronald L. Horst, Tayyaba Hasan, Edward V. Maytin
      Pages: n/a - n/a
      Abstract: Photodynamic therapy (PDT), in which 5‐ALA (a precursor for protoporphyrin IX, PpIX) is administered prior to exposure to light, is a nonscarring treatment for skin cancers. However, for deep tumors, ALA‐PDT is not always effective due to inadequate production of PpIX. We previously developed and reported a combination approach in which the active form of vitamin D3 (calcitriol) is given systemically prior to PDT to improve PpIX accumulation and to enhance PDT‐induced tumor cell death; calcitriol, however, poses a risk of hypercalcemia. Here, we tested a possible strategy to circumvent the problem of hypercalcemia by substituting natural dietary vitamin D3 (cholecalciferol; D3) for calcitriol. Oral D3 supplementation (10 days of a 10‐fold elevated D3 diet) enhanced PpIX levels 3‐ to 4‐fold, and PDT‐mediated cell death 20‐fold, in subcutaneous A431 tumors. PpIX levels and cell viability in normal tissues were not affected. Hydroxylated metabolic forms of D3 were only modestly elevated in serum, indicating minimal hypercalcemic risk. These results show that brief oral administration of cholecalciferol can serve as a safe neoadjuvant to ALA‐PDT. We suggest a clinical study, using oral vitamin D3 prior to PDT, should be considered to evaluate this promising new approach to treating human skin cancer. We report the results of a preclinical study in mice, showing that a combination of oral vitamin D (vit D3) and PDT can improve therapeutic killing of subcutaneous SCC tumors without the risk of hypercalcemia usually associated with calcitriol, the active hormonal form of vit D3. Dietary supplementation with vit D3 (10 days) enhanced PpIX levels, promoted tumor differentiation and proliferation and resulted in enhanced tumor cell death following PDT. These data suggest that a clinical study using oral vit D3 prior to PDT could establish a promising new approach for effective therapy of nonmelanoma skin cancer.
      PubDate: 2014-05-25T23:46:50.697173-05:
      DOI: 10.1111/php.12286
  • Risk of Ocular Exposure to Biologically Effective UV Radiation in
           Different Geographical Directions
    • Authors: Fang Wang; Liwen Hu, Qian Gao, Yanyan Gao, Guangcong Liu, Yang Zheng, Yang Liu
      Pages: n/a - n/a
      Abstract: To quantify ocular exposure to solar ultraviolet radiation (UVR) and to assess the risk of eye damage in different geographical directions due to UVR exposure, we used a spectrometer and a manikin to measure horizontal ambient and ocular exposure UVR in different geographical directions at four different locations at the Northern Hemisphere. Describing the relationship of exposure to risk of eye damage requires the availability of UV hazard weighting function. So, we used the UV hazard weighting function (ICNIRP) proposed by International Commission on Non‐Ionizing Radiation Protection to determine the biologically effective UV irradiance (UVBEeye) and then cumulative effective radiant exposure (Heye) to shown the risk of eye. We found that in different geographical directions, distributions of ocular exposure to UVR were markedly different from those of horizontal ambient UVR. When the midday maximum SEA > 50°, eye received more UVR from the east and west directions during the morning and evening hours, respectively. However, when the midday maximum SEA 
      PubDate: 2014-05-23T02:26:28.883417-05:
      DOI: 10.1111/php.12287
  • Photooxidation of Tetrahydrobiopterin under UV Irradiation: Possible
           Pathways and Mechanisms
    • Authors: Andrey A. Buglak; Taisiya A. Telegina, Tamara A. Lyudnikova, Yulia L. Vechtomova, Mikhail S. Kritsky
      Pages: n/a - n/a
      Abstract: Tetrahydrobiopterin (H4Bip) is a cofactor for several key enzymes, including NO synthases and aromatic amino acid hydroxylases (AAHs). Normal functioning of the H4Bip regeneration cycle is extremely important for the work of AAHs. Oxidized pterins may accumulate if the H4Bip regeneration cycle is disrupted or if H4Bip autoxidation occurs. These oxidized pterins can photosensitize the production of singlet molecular oxygen 1O2 and thus cause oxidative stress. In this context, we studied the photooxidation of H4Bip in phosphate buffer at pH 7.2. We found that UV irradiation of H4Bip affected its oxidation rate (quantum yield Φ300 = (2.7 ± 0.4) × 10−3). The effect of UV irradiation at λ = 350 nm on H4Bip oxidation was stronger, especially in the presence of biopterin (Bip) (Φ350 = (9.7 ± 1.5) × 10−3). We showed that the rate of H4Bip oxidation linearly depends on Bip concentration. Experiments with KI, a selective quencher of triplet pterins at micromolar concentrations, demonstrated that the oxidation is sensitized by the triplet state biopterin 3Bip. Apparently, electron transfer sensitization (Type‐I mechanism) is dominant. Energy transfer (Type‐II mechanism) and singlet oxygen generation play only a secondary role. The mechanisms of H4Bip photooxidation and their biological meaning are discussed. The photochemistry of tetrahydrobiopterin (H4Bip) has never been studied, probably because it is pretty unstable. This cofactor is essential for higher organisms as it participates in several important biocatalytic reactions. We studied the photooxidation of H4Bip using HPLC and absorption spectroscopy. The process of H4Bip oxidation is induced by triplet state biopterin 3Bip. Apparently, electron transfer sensitization (Type‐I mechanism) is dominant. Energy transfer (Type‐II mechanism) and singlet oxygen generation play only a secondary role. The mechanisms of H4Bip photooxidation and their biological application are discussed in the context of vitiligo etiology.
      PubDate: 2014-05-20T01:28:08.047429-05:
      DOI: 10.1111/php.12285
  • Therapeutic Effects of Full Spectrum Light on the Development of Atopic
           Dermatitis‐like Lesions in NC/Nga Mice
    • Authors: Tae‐Rin Kwon; Seog Kyun Mun, Chang Taek Oh, Hyuckki Hong, Yeon Shik Choi, Bong‐Jun Kim, Beom Joon Kim
      Pages: n/a - n/a
      Abstract: Full spectrum light (FSL) includes UVA, visible light and infrared light. Many studies have investigated the application of FSL in severe cases of atopic dermatitis (AD) in humans; however, FSL has not yet been studied in an animal model. The purpose of this study was to evaluate the therapeutic effects of FSL on AD‐like skin lesions using NC/Nga mice, with the aim of mitigating itching and attenuating the expression of adhesion molecules. We examined the effects of FSL on mite allergen‐treated NC/Nga mice by assessing skin symptom severity, ear thickness, serum IgE levels, and the cytokine expression. We examined the histology of lesions using hematoxylin–eosin, toluidine blue and immunohistochemical staining. Our findings suggest that FSL phototherapy exerts positive therapeutic effects on Dermatophagoides farinae (Df)‐induced AD‐like skin lesions in NC/Nga mice by reducing IgE levels, thus promoting recovery of the skin barrier. The mechanisms by which FSL phototherapy exerts its effects may also involve the inhibition of scratching behavior, reduction of IL‐6 levels and reductions in adhesion molecule expression. The present study indicates that FSL phototherapy inhibits the development of AD in NC/Nga mice by suppressing cytokine, chemokine and adhesion molecule expression, and thus, could potentially be useful in treating AD. Full spectrum light includes UVA, visible light and infrared light. FSL phototherapy exerts positive therapeutic effects on Df‐induced AD‐like skin lesions in NC/Nga mice by reducing IgE levels, thus promoting recovery of the skin barrier. The mechanisms by which FSL phototherapy exerts its effects may involve the inhibition of scratching behavior, reduction of IL‐6 levels and reductions in the levels of expression of adhesion molecules. The present study indicates that FSL phototherapy inhibits the development of AD in NC/Nga mice by suppressing the expression of cytokines, chemokines and adhesion molecules, and thus could potentially be useful in treating AD.
      PubDate: 2014-05-19T04:05:44.278613-05:
      DOI: 10.1111/php.12284
  • Reversible Effects of Photodamage Directed Toward Mitochondria
    • Authors: David Kessel
      Pages: n/a - n/a
      Abstract: When the initial effect of photodynamic therapy (PDT) involves mitochondrial photodamage, an early effect is loss of the mitochondrial membrane potential (ΔΨm). Using murine hepatoma 1c1c7 cells and a photosensitizing agent known to target mitochondria, we examined loss of ΔΨm, initiation of apoptosis and loss of viability as a function of time and light dose. There was a correlation between loss of viability and the rapid disappearance of ΔΨm, as detected by the potential‐sensitive probe Mitotracker Orange (MTO). Loss of ΔΨm was, however, reversible even with a substantial loss of viability. Unless there was a supralethal level of photodamage, 1c1c7 cells recovered their mitochondrial membrane potential, even if the cell population was on the pathway to apoptosis and cell death. These results indicate that when mitochondria are the initial PDT target, a qualitative estimate of photokilling can be provided by assessing the initial loss of ΔΨm. Loss of mitochondrial membrane potential (Δψm) directly after mitochondrial photodamage predicts for the subsequent loss of viability as determined by a clonogenic assay. MitoTracker Orange was used as the fluorescent probe for Δψm.
      PubDate: 2014-05-14T01:41:55.27826-05:0
      DOI: 10.1111/php.12283
  • Activation of Sperm EGFR by Light Irradiation is Mediated by Reactive
           Oxygen Species
    • Authors: Shiran Shahar; Pnina Hillman, Rachel Lubart, Debby Ickowicz, Haim Breitbart
      Pages: n/a - n/a
      Abstract: To acquire fertilization competence, spermatozoa must undergo several biochemical and motility changes in the female reproductive tract, collectively called capacitation. Actin polymerization and the development of hyperactivated motility (HAM) are part of the capacitation process. In a recent study, we showed that irradiation of human sperm with visible light stimulates HAM through a mechanism involving reactive‐oxygen‐species (ROS), Ca2+ influx, protein kinases A (PKA), and sarcoma protein kinase (Src). Here, we showed that this effect of light on HAM is mediated by ROS‐dependent activation of the epidermal growth factor receptor (EGFR). Interestingly, ROS‐mediated HAM even when the EGFR was activated by EGF, the physiological ligand of EGFR. Light irradiation stimulated ROS‐dependent actin polymerization, and this effect was abrogated by PBP10, a peptide which activates the actin‐severing protein, gelsolin, and causes actin‐depolymerization in human sperm. Light‐stimulated tyrosine phosphorylation of Src‐dependent gelsolin, resulting in enhanced HAM. Thus, light irradiation stimulates HAM through a mechanism involving Src‐mediated actin polymerization. Light‐stimulated HAM and in vitro‐fertilization (IVF) rate in mouse sperm, and these effects were mediated by ROS and EGFR. In conclusion, we show here that irradiation of sperm with visible light, enhances their fertilization capacity via a mechanism requiring ROS, EGFR and HAM. We previously showed that light irradiation of human sperm induces ROS production in the mitochondria. In turn, ROS activate voltage–dependent‐Ca2+ channels causing elevation of intracellular Ca2+ which activates soluble adenylyl cyclase (sAC) resulting in cAMP production and PKA activation. We also show that PKA activates Src, which phosphorylates EGFR and gelsolin, resulting in increased actin polymerization and hyperactivation. Here, we show that visible‐light irradiation of human spermatozoa, enhances ROS‐dependent‐EGFR phosphorylation/activation and actin polymerization leading to stimulation of hyperactivated motility. Moreover, light irradiation of mouse sperm enhances fertilization capacity mediated by ROS, EGFR and hyperactivated motility.
      PubDate: 2014-05-02T04:12:21.43452-05:0
      DOI: 10.1111/php.12281
  • Photoactive Titania Float for Disinfection of Water; Evaluation of Cell
           Damage by Bioanalytical Techniques
    • Authors: R. Shwetharani; M. S. Jyothi, P. D. Laveena, R. Geetha Balakrishna
      Pages: n/a - n/a
      Abstract: A photoactive float was fabricated with the modified titania to cause a feasible disinfection of water, contaminated with E. coli. The commercially available titania was doped with neodymium by pulverization technique to enhance its activity in sunlight and a multiapproach technique was used to evaluate the extended efficiency of the doped sample. X‐ray diffraction patterns depicted the retention of anatase phase on doping and the existence of neodymium was confirmed by the energy dispersive atomic X‐ray analysis and the X‐ray photoelectron spectroscopy. Transmission electron microscopy and Bruner–Emmett–Teller analysis depicted a marginal increase in the particle size and a decrease in the surface area, respectively. Doping induces semiconductor behavior with lower band energy that could respond to visible light and exhibit better disinfection activity. The “f” and “d” transitions of the lanthanide in doped sample caused new electronic behavior of trapping/detrapping effect together with bandgap narrowing. The amount of malondialdehyde, protein, DNA and RNA released on destruction of E. coli was observed to be 0.915 × 10−3 μg mL−1, 859.912 μg mL−1, 20.173 μg mL−1 and 1146.073 μg mL−1, respectively. The above analytical methods along with standard plate count method substantiated the enhanced disinfection efficiency of the doped sample in sunlight. The titania‐coated polymeric float effectively disintegrates the bacteria by adsorption and diffusion to cause complete disintegration of cell membrane and thus disinfects water.
      PubDate: 2014-04-25T02:24:21.840183-05:
      DOI: 10.1111/php.12277
  • Preliminary Ultrasonication Affects the Rate of the Bacteriorhodopsin
           Bleaching and the Effectiveness of the Reconstitution Process in
    • Authors: Anna B. Druzhko; Sergey K. Pirutin
      Pages: n/a - n/a
      Abstract: The formation process of polymer films based on bacteriorhodopsin (BR) analogs requests a high amount of BR samples one time only. The common technique for apomembrane formation (preparation of bacterioopsin, BO) is not designed to be operated with high concentrations and high volumes of BR, so the use of this technique results in a low rate of BR bleaching. To accelerate the process of BR bleaching preliminary sonication was used. It was used just as preliminary sonication before bleaching of BR samples, so also sonication was used before reconstitution of resulted BO samples. These modifications of the common technique lead to an acceleration of BR bleaching and an increase in effectiveness of reconstitution of BO in comparison with the nonmodified technique. The quantitative results of sonication's effect on the bleaching acceleration and the effectiveness of reconstitution are different depending on the BR strains. A high‐concentrated BR suspension is bleached in a PHA reaction at a very low rate. To accelerate this reaction the preliminary ultrasonication (kGz range) has been used. This is largely responsible for increasing the rate of this reaction and high quality of resulted apomembrane. A further process of apomembrane reconstitution with retinal relies upon preliminary ultrasonication (kGz range) of a high‐concentrated apomembrane either. After ultrasonication the effectiveness of reconstitution has been increased. The quantitative characteristics of two processes depend upon types of BR strains. So, we offer a simple way to enhance the PM bleaching and AM reconstitution.
      PubDate: 2014-04-21T00:56:14.708601-05:
      DOI: 10.1111/php.12275
  • Sun exposure and Protection Behavior of Danish Farm Children: Parental
           Influence on Their Children
    • Authors: Mette Bodekær Larsen; Bibi Petersen, Peter Alshede Philipsen, Antony Young, Elisabeth Thieden, Hans Christian Wulf
      Pages: n/a - n/a
      Abstract: Healthy sun habits acquired in childhood could reduce skin cancer incidence. We examined the sun exposure and protection behavior of an expected high‐exposure group of children, and the association to their parents. Open, prospective cohort study. One hundred and thirty nine participants (40 families) kept daily sun behavior diaries (sun exposure, sunscreen use, sunburns) over a 4‐month summer period (15 985 diary days). The Pigment Protection Factor (PPF), an objective measure of sun exposure, was measured at two body sites, before and after summer. All participants presented data from the same 115 days. Risk behavior (sun exposure of upper body) took place on 9.5 days (boys) and 15.6 days (girls). Sunburn and sunscreen use were infrequent. Boys’ sun exposure resulted in an increased photo protection over the study period of 1.7 SED (upper arm) and 0.8 SED (shoulder) to elicit erythema. Corresponding values for girls were as follows: 0.9 SED (upper arm) and 0.5 SED (shoulder). Boys’ sunscreen use correlated to their mothers’ (r = 0.523, P = 0.02). Girls’ number of risk days (r = 0.552, P = 0.005) and sun exposure (upper arm: r = 0.621, P 
      PubDate: 2014-04-21T00:56:11.670107-05:
      DOI: 10.1111/php.12280
  • “Pointsource” Delivery of a Photosensitizer Drug and Singlet
           Oxygen: Eradication of Glioma Cells In Vitro
    • Authors: Ashwini A. Ghogare; Imran Rizvi, Tayyaba Hasan, Alexander Greer
      Pages: n/a - n/a
      Abstract: We describe a pointsource sensitizer‐tipped microoptic device for the eradication of glioma U87 cells. The device has a mesoporous fluorinated silica tip which emits singlet oxygen molecules and small quantities of pheophorbide sensitizer for additional production of singlet oxygen in the immediate vicinity. The results show that the device surges in sensitizer release and photokilling with higher rates about midway through the reaction. This was attributed to a self‐amplified autocatalytic reaction where released sensitizer in the extracellular matrix provides positive feedback to assist in the release of additional sensitizer. The photokilling of the glioma cells was analyzed by global toxicity and live/dead assays, where a killing radius around the tip with ~0.3 mm precision was achieved. The implication of these results for a new PDT tool of hard‐to‐resect tumors, e.g. in the brain, is discussed. A sensitizer‐tipped microoptic device for the eradication of glioma U87 cells is described. The device has a porous silica tip that emits 1O2 molecules and small quantities of pheophorbide sensitizer for additional production of 1O2 in the immediate vicinity. The implication of these results for a new PDT tool of hard‐to‐resect tumors, e.g. in the brain, is discussed.
      PubDate: 2014-04-21T00:54:44.205021-05:
      DOI: 10.1111/php.12274
  • Excited State Photoreaction between the Indole Side Chain of Tryptophan
           and Halocompounds Generates New Fluorophores and Unique Modifications
    • Authors: Carol L. Ladner; Khai Tran, Mary Le, Raymond J. Turner, Robert A. Edwards
      Pages: n/a - n/a
      Abstract: Photoreaction of indole containing compounds with chloroform and other trichlorocompounds generates products with redshifted fluorescence. In proteins, this reaction can be used for the fluorescent detection of proteins. Little characterization of products generated through the photochemical reaction of indoles with halocompounds has been done, yet is fundamental for the development of other fluorophores, protein labeling agents, and bioactive indole derivatives. Here, we have characterized which isomers form in the photoreaction between tryptophan and chloroform using 1H‐NMR of tryptophan and methylated derivatives to reveal that the two major products that are formed result from modification at the 4‐ and 6‐carbon positions of the indole ring. Reaction at position 6 generates 6‐formyl tryptophan and the reaction at position 4 generates an imine because the formyl derivative that is initially formed reacts further with the tryptophan amine group. The spectroscopic properties and product molecular weights of photoproducts formed from photoreaction of tryptophan with other trihalo and monohalocompounds are also determined. The indole ring of tryptophan can be modified with various additions from halocompounds, including the addition of labels to the indole ring via methylene groups. This opens possibilities for generating novel tryptophan based fluorophores and protein labeling strategies using this photochemistry. Several fluorophores were produced by photoreactions between the amino acid tryptophan and halocompounds. The reaction with trihalocompounds in aqueous solution yielded products with carbonyl groups conjugated to the aromatic system at the 4 and 6 positions of the indole fluorophore and led to emission near 500 nm. This photoreaction also proceeded with monohalocompounds, but resulted in additions to the indole fluorophore without enlarging the conjugated systems so that the fluorescence properties of the indole in tryptophan did not change significantly.
      PubDate: 2014-04-17T05:54:23.005685-05:
      DOI: 10.1111/php.12279
  • Observation of Magnetic Field Effects on Transient Fluorescence Spectra of
           Cryptochrome 1 From Homing Pigeons
    • Authors: Xian‐li Du; Jing Wang, Wei‐song Pan, Qi‐jun Liu, Xiao‐jie Wang, Wen‐jian Wu
      Pages: n/a - n/a
      Abstract: Cryptochromes are suggested to be involved in the bird magnetoreception based on the radical pair mechanism (RPM), a well established theory of weak magnetic field effects on chemical reactions. Two members of cryptochrome/photolyase family were found to respond to magnetic field, however, no direct responses of bird cryptochrome to magnetic field as weak as the Earth's magnetic field have been obtained so far. In this study, we used transient fluorescence spectroscopy to characterize the weak magnetic field effects of bird cryptochromes. To do this, we cloned the cryptochrome 1 gene (clCRY1) from the retina of homing pigeons (Columba livia), expressed it in insect Sf9 cells and analyzed the transient fluorescence of purified clCRY1 by application of 45–300 μT magnetic fields. The flavin adenine dinucleotide (FADox) and glucose oxidase (GOD) in PBS buffer were set as controls which could be excited by light to generate radicals, but would not be sensitive to magnetic field. We observed that the transient fluorescence spectra of clCRY1 were sensitive to the applied magnetic field at room temperature. Our result provides a new proof of the cryptochrome‐based model of avian magnetoreception in vitro. Cryptochrome is suggested to be the most probable candidate magnetoreceptor in bird magnetoreception. Two members of cryptochrome/photolyase family have been found to be sensitive to the magnetic field and the magnetic sensitivity was proposed to be the general feature of this protein family. In this study, we constructed a magnetic field by Helmholtz coils and tested the magnetic field effects on the transient fluorescence of cryptochrome from homing pigeons at room temperature. Our results showed that, comparing to other flavin controls, the transient fluorescence of clCRY1 protein is sensitive to microtesla level magnetic field.
      PubDate: 2014-04-17T05:54:05.966108-05:
      DOI: 10.1111/php.12276
  • Chlorin e6 Derivative Radachlorin Mainly Accumulates in Mitochondria,
           Lysosome and Endoplasmic Reticulum and Shows High Affinity toward Tumors
           in Nude Mice in Photodynamic Therapy
    • Authors: Raktim Biswas; Jeong Hwan Moon, Jin‐Chul Ahn
      Pages: n/a - n/a
      Abstract: The efficacy of photodynamic therapy (PDT) depends upon the amount of photosensitizer accumulated in the malignant tissues. Radachlorin is a popular photosensitizer used in photodynamic therapy to treat various types of cancer. In this study, we have studied the main organelles responsible for the accumulation of radachlorin in human anaplastic thyroid cancer in vitro and in vivo. The optimal time window for uptake and clearance of radachlorin also was studied. Confocal microscopic images confirmed that the radachlorin is mainly acquired by mitochondria and partially by lysosome and endoplasmic reticulum. Studies also showed that the maximum amount of radachlorin was accumulated within 3–6 h after the treatment. Radachlorin also showed a higher affinity toward malignant tumors compared to the other organs in mice xenograft model. Uptake of radachlorin reached an optimum amount within 6 h and most of the radachlorins were also cleared from the body in next 48 h. Therefore, detailed information regarding exact accumulation sites and a time window in which maximum amount of drug is accumulated and cleared were obtained by this study. Hence, not only the efficacy of the treatment can be increased but the phototoxicity after the treatment also can be controlled. Cellular uptake and tumor affinity of chlorin e6 photosensitizer, radachlorin were studied in anaplastic thyroid cancer cells and xenograft nude mice model. Results showed radachlorin mainly accumulated in mitochondria and partially in lysosome and endoplasmic reticulum. It showed a higher accumulation in tumor site within 3–6 h and was further cleared from the tumor in next 24–48 h. Radachlorin also showed a higher efficacy in photodynamic therapy after 6 h of drug injection. Therefore, the knowledge of possible sites and time of photosensitizers accumulation in tumor cells may help in optimizing the efficacy of PDT.
      PubDate: 2014-04-17T05:54:04.254351-05:
      DOI: 10.1111/php.12273
  • A Tandem Mass Spectrometric Method for Singlet Oxygen Measurement
    • Authors: Maarit Karonen; Heta Mattila, Ping Huang, Fikret Mamedov, Stenbjörn Styring, Esa Tyystjärvi
      First page: 965
      Abstract: Singlet oxygen, a harmful reactive oxygen species, can be quantified with the substance 2,2,6,6‐tetramethylpiperidine (TEMP) that reacts with singlet oxygen, forming a stable nitroxyl radical (TEMPO). TEMPO has earlier been quantified with electron paramagnetic resonance (EPR) spectroscopy. In the present study, we designed an ultra‐high‐performance liquid chromatographic – tandem mass spectrometric (UHPLC‐ESI‐MS/MS) quantification method for TEMPO and showed that the method based on multiple reaction monitoring (MRM) can be used for the measurements of singlet oxygen from both non‐biological and biological samples. Results obtained with both UHPLC‐ESI‐MS/MS and EPR methods suggest that plant thylakoid membranes produce 3.7 x 10‐7 molecules of singlet oxygen per chlorophyll molecule in a second when illuminated with the photosynthetic photon flux density of 2000 μmol m‐2s‐1. This article is protected by copyright. All rights reserved.
      PubDate: 2014-06-20T03:00:43.170111-05:
      DOI: 10.1111/php.12291
  • Photophysics, Excited‐state Double‐Proton Transfer and
           Hydrogen‐bonding Properties of 5‐Deazaalloxazines
    • Authors: Dorota Prukala; Igor Khmelinskii, Jacek Koput, Mateusz Gierszewski, Tomasz Pędziński, Marek Sikorski
      First page: 972
      Abstract: The photophysical properties of 5‐deazaalloxazine and 1,3‐dimethyl‐5‐deazaalloxazine were studied in different solvents. These compounds have higher values of fluorescence quantum yields and longer fluorescence lifetimes, compared to those obtained for their alloxazine analogs. Electronic structure and S0–Si transitions were investigated using the ab initio methods [MP2, CIS(D), EOM‐CCSD] with the correlation‐consistent basis sets. Also the time‐dependent density functional theory (TD‐DFT) has been employed. The lowest singlet excited states of 5‐deazaalloxazine and 1,3‐dimethyl‐5‐deazaalloxazine are predicted to have the π, π* character, whereas similar alloxazines have two close‐lying π, π* and n, π* transitions. Experimental steady‐state and time‐resolved spectral studies indicate formation of an isoalloxazinic excited state via excited‐state double‐proton transfer (ESDPT) catalyzed by an acetic acid molecule that forms a hydrogen bond complex with the 5‐deazaalloxazine molecule. Solvatochromism of both 5‐deazaalloxazine and its 1,3‐dimethyl substituted derivative was analyzed using the Kamlet–Taft scale and four‐parameter Catalán solvent scale. The most significant result of our studies is that the both scales show a strong influence of solvent acidity (hydrogen bond donating ability) on the emission properties of these compounds, indicating the importance of intermolecular solute–solvent hydrogen‐bonding interactions in their excited state. Photophysics of 5‐deazaalloxazine and its 1,3‐methyl substituted derivatives in different solvents indicate strong influence of solvent acidity on their emission properties. The experimental results are compared to the theoretical calculations on different level of theory. Excited‐state double‐proton transfer of 5‐deazaalloxazine in methylene chloride in the presence of acetic acid has been detected and studied.
      PubDate: 2014-06-05T06:04:23.508009-05:
      DOI: 10.1111/php.12289
  • Influence of Dye Content on the Conduction Band Edge of Titania in the
           Steam‐Treated Dye‐Dispersing Titania Electrodes
    • Authors: Rudi Agus Setiawan; Hiromasa Nishikiori, Nobuaki Tanaka, Tsuneo Fujii
      First page: 1004
      Abstract: The titania and dye‐dispersing titania electrodes were prepared by a nitric acid‐catalyzed sol‐gel process. The dye‐dispersing titania contains the dye molecules dispersed on the surface of the individual nanosized titania particles. The photo‐cyclic voltammetry (Photo‐CV) and photoelectric measurements of the dye‐dispersing titania electrodes were conducted in order to clarify the factors changing the conduction band edge of the titania and the open‐circuit voltage (Voc) of the electrodes. The remaining nitrate ions caused a negative shift of conduction band edge of the titania of the dye‐dispersing titania. The conduction band edge of the titania was shifted in a negative direction in the electrode containing a greater amount of the dye. These results are due to the adsorption of nitrate ions and the dye‐titania complex formation on the titania particle surface. The effect of the dye‐titania complex formation on the shift in the titania conduction band edge was greater than that of the adsorption of nitrate ions due to strong interaction between the dye and titania through the carboxylate and quinone‐like groups of the dye. The shift in the titania conduction band edge corresponded to the change in the Voc value. This article is protected by copyright. All rights reserved.
      PubDate: 2014-06-04T01:30:24.296136-05:
      DOI: 10.1111/php.12297
  • Possible Involvement of a Tetrahydrobiopterin in Photoreception for
           UV‐B‐induced Anthocyanin Synthesis in Carrot
    • Authors: Junko Takeda; Rieko Nakata, Hiroshi Ueno, Akio Murakami, Mineo Iseki, Masakatsu Watanabe
      First page: 1043
      Abstract: Our previous studies of action spectra for UV‐B‐induced anthocyanin accumulation in cultured carrot cells indicated that a reduced form of pterin, possibly tetrahydrobiopterin, contributes to UV‐B photoreception. In this report, we provide additional evidence for the involvement of pterin in UV‐B light sensing. UV‐B‐induced phenylalanine ammonia‐lyase (PAL) activity was considerably suppressed by N‐acetylserotonin (an inhibitor of tetrahydrobiopterin biosynthesis), and this suppression was partially recovered by adding biopterin or tetrahydrobiobiopterin. In addition, protein(s) specifically bound to biopterin were detected by radiolabeling experiments in N‐acetylserotonin‐treated cells. Furthermore, diphenyleneiodonium, a potent inhibitor of electron transfer, completely suppressed UV‐B‐induced PAL activity. These results suggest the occurrence of an unidentified UV‐B photoreceptor (other than UVR8, the tryptophan‐based UV‐B sensor originally identified in Arabidopsis) with reduced pterin in carrot cells. After re‐examining published action spectra, we suggest that anthocyanin synthesis is coordinately regulated by these two UV‐B sensors. This article is protected by copyright. All rights reserved.
      PubDate: 2014-06-19T01:55:46.857696-05:
      DOI: 10.1111/php.12302
  • Effects of Ultraviolet Radiation (UVA+UVB) on Young Gametophytes of
           Gelidium floridanum: Growth rate, Photosynthetic Pigments, Carotenoids,
           Photosynthetic Performance and Ultrastructure
    • Authors: Carmen Simioni; Éder C. Schmidt, Marthiellen R. de L. Felix, Luz Karime Polo, Ticiane Rover, Marianne Kreusch, Debora T. Pereira, Fungyi Chow, Fernanda Ramlov, Marcelo Maraschin, Zenilda L. Bouzon
      First page: 1050
      Abstract: This study investigated the effects of radiation (PAR+UVA+UVB) on the development and growth rates of young gametophytes of Gelidium floridanum. In addition, photosynthetic pigments were quantified, carotenoids identified, and photosynthetic performance assessed. Over a period of 3 days, young gametophytes were cultivated under laboratory conditions and exposed to photosynthetically active radiation (PAR) at 80 μmol photons m−2 s−1 and PAR+UVA (0.70 W m−2) +UVB (0.35 W m−2) for 3 h per day. The samples were processed for light and electron microscopy to analyze the ultrastructure features, as well as carry out metabolic studies of growth rates, quantify the content of photosynthetic pigments, identify carotenoids and assess photosynthetic performance. PAR+UVA+UVB promoted increase of cell wall thickness, accumulation of floridean starch grains in the cytoplasm and disruption of chloroplast internal organization. Algae exposed to PAR+UVA+UVB also showed a reduction in growth rate of 97%. Photosynthetic pigments, in particular, phycoerythrin and allophycocyanin contents, decreased significantly from UV radiation exposure. This result agrees with the decrease of photosynthetic performance observed after exposure to UVR, as measured by a decrease in the electron transport rate (ETR), where values of ETRmax declined approximately 44.71%. It can be concluded that radiation is a factor that affects the young gametophytes of G. floridanum at this stage of development. This article is protected by copyright. All rights reserved.
      PubDate: 2014-06-23T05:16:45.736292-05:
      DOI: 10.1111/php.12296
  • The Light Induced FOS Response in Melanopsin Expressing HEK‐293
           Cells Is Correlated to Melanopsin Quantity And Dependent on Light Duration
           And Irradiance
    • Authors: Birgitte Georg; Lene Rask, Jens Hannibal, Jan Fahrenkrug
      First page: 1069
      Abstract: We established a cell line (HEK‐hMel) expressing melanopsin in a tetracycline dependent manner to elucidate new aspects of melanopsin's light response. Different light stimuli were evaluated using FOS expression as response parameter. Immunoblotting was used to evaluate expression of melanopsin and FOS and qPCR to quantify FOS mRNA responses. The magnitude of the FOS response was found to correlate with the amount of melanopsin expressed by the cells, and a transient FOS mRNA induction followed by FOS protein still elevated after 24 h of illumination was revealed. Exposing the cells to darkness after light resulted in reduction of the response compared to exposure to light solely showing dependency on continuous light. Increasing irradiances of blue light (480 nm) up to 1011 quanta x cm−2 x s−1 elicited steep increases in FOS mRNA, while increases between 1012 and 5 x 1013 quanta x cm−2 x s−1 resulted in equally high FOS expression. The HEK‐hMel cells were used to characterize facets of melanopsin's light induced FOS response not approachable in vivo. Novel information such as dependency of the FOS response on both melanopsin amount and light intensity in addition to a detailed time‐course of both FOS mRNA and protein were revealed. This article is protected by copyright. All rights reserved.
      PubDate: 2014-06-09T05:05:51.846635-05:
      DOI: 10.1111/php.12298
  • Comparative Antibacterial Efficacy of Photodynamic Therapy and Ultrasonic
           Irrigation Against Enterococcus faecalis In Vitro
    • Authors: Yanhuang Wang; Xiaojing Huang
      First page: 1084
      Abstract: Enterococcus faecalis poses a challenge to the efficacy of traditional root canal disinfection methods. This study was aimed to establish a synergistic root canal disinfection strategy combining ultrasonic irrigation with photodynamic therapy (PDT) together and to test its antibacterial efficacy against E. faecalis. Twenty‐seven bovine root canals infected with E. faecalis were randomly divided into three groups and treated with different disinfection methods as follows: ultrasonic irrigation with 2.5% NaOCl, methylene blue (MB)‐mediated PDT, or combined ultrasonic irrigation and PDT as described above. Quantification of E. faecalis was performed on the root canals before and immediately after the disinfection treatment. Residual bacteria were determined by counting colony‐forming units. Samples were randomly selected from the three groups, and the morphology of residual bacteria inside the dentinal tubules was studied by scanning electron microscopy. The number of surviving E. faecalis in the group treated with the combination method was significantly lower (P 
      PubDate: 2014-06-18T06:53:02.055236-05:
      DOI: 10.1111/php.12293
  • Neurotransmitter transporter family including SLC6A6 and SLC6A13
           contributes to the 5‐aminolevulinic acid (ALA)‐induced
           accumulation of protoporphyrin IX and photo‐damage, through uptake
           of ALA by cancerous cells
    • Authors: Tai Tien Tran; Anfeng Mu, Yuka Adachi, Yasushi Adachi, Shigeru Taketani
      First page: 1136
      Abstract: δ‐Aminolevulinic acid (ALA)‐induced protoporphyrin accumulation is widely used in the treatment of cancer, as photodynamic therapy (PDT). To clarify the mechanisms of ALA uptake by tumor cells, we have examined the ALA‐induced accumulation of protoporphyrin by the treatment of colon cancer DLD‐1 and epithelial cancer HeLa cells with γ‐aminobutyric acid (GABA)‐related compounds. When the cells were treated with GABA, taurine and β‐alanine, the level of protoporphyrin was decreased, suggesting that plasma membrane transporters involved in the transport of neurotransmitters contribute to the uptake of ALA. By transfection with neurotransmitter transporters SLC6A6, SLC6A8 and SLC6A13 cDNA, the ALA‐ and ALA methylester‐dependent accumulation of protoporphyrin markedly increased in HEK293T cells, dependent on an increase in the uptake of ALA. When ALA‐treated cells were exposed to white light, the extent of photo‐damage increased in SLC6A6‐ and SLC6A13‐expressing cells. Conversely, knockdown of SLC6A6 or SLC6A13 with siRNAs in DLD‐1 and HeLa cells decreased the ALA‐induced accumulation. The expression of SLC6A6 and SLC6A13 was found in some cancer cell lines. Immunohistochemical studies revealed that the presence of these transporters was elevated in colon cancerous cells. These results indicated that neurotransmitter transporters including SLC6A6 and SLC6A13 mediate the uptake of ALA and can play roles in the enhancement of ALA‐induced accumulation of protoporphyrin in cancerous cells. This article is protected by copyright. All rights reserved.
      PubDate: 2014-06-23T05:15:17.916808-05:
      DOI: 10.1111/php.12290
  • 5‐aminolaevulinicacid (ALA)‐loaded fullerene nanoparticles for
           in vitro and in vivo photodynamic therapy
    • Authors: Zhi Li; Li-li Pan, Fei-long Zhang, Xia-li Zhu, Yang Liu, Zhen-zhong Zhang
      First page: 1144
      Abstract: This report explores some properties of 80‐200 nm nanoparticles containing 5‐aminolevulinic acid (ALA) and fullerene (C60) for photodynamic therapy. Compared with ALA, the nanoparticles yielded more protoporphytin (PpIX) formation in cells and tissues and to a significant improvement in antitumor efficacy in tumor‐bearing mice. Maximum levels of PpIX were obtained 4 h after administration and selective PpIX formation in tumor was observed. These nanoparticles appear to be a useful vehicle for drug delivery purposes. In this paper, a procedure for preparing fullerene nanoparticles containing ALA was developed. The product alone exhibited no detectable toxicity in the dark and was superior to ALA alone in promoting PpIX biosynthesis and PDT efficacy both in culture and in a murine tumor model. These results suggest that this procedure could be the basis for an improved PDT protocol for cancer control. This article is protected by copyright. All rights reserved.
      PubDate: 2014-06-10T00:34:33.439093-05:
      DOI: 10.1111/php.12299
  • UVER dose received by golfers in winter, in Valencia
    • Authors: Gonzalo Gurrea Ysasi; Juan Carlos Moreno, Mª Antonia Serrano
      First page: 1170
      Abstract: This paper analyses UVER (Ultraviolet Erythematic Radiation) dose received by several golf players in winter in Valencia. Playing golf involves spending several hours outdoors because of the length of golf matches and training. Moreover, in Valencia there are many golf players coming from northern Europe, with a phototype very sensitive (I‐II). For that reason these people have an increasing risk while playing. This paper shows that harmful effects coming from UVER radiation may occur not only in summer time but also in winter, especially at these latitudes. VioSpor dosimeters have been used in order to develop this analysis over several golf players on January 2013 between 10:00h and 15:00h, local time. This article is protected by copyright. All rights reserved.
      PubDate: 2014-06-04T01:30:21.225555-05:
      DOI: 10.1111/php.12295
  • On the Role of Exponential Smoothing in Circadian Dosimetry
    • Authors: Luke L. A. Price
      First page: 1184
      Abstract: The effects lighting has on health through modulation of circadian rhythms are becoming increasingly well documented. Data are still needed to show how light exposures are influenced by architecture and lighting design and circadian dosimetry analyses should provide duration, phase and amplitude measures of 24-hour exposure profiles. Exponential smoothing is used to derive suitable metrics from 24-hour light measurements collected from private dwellings. A further application of these modified exposure time series as physiological models of the light drive is discussed. Unlike previous light drive models, the dose rate persists into periods of darkness following exposures. Comparisons to long duration exposure studies suggest this type of persistent light drive model could be incorporated into contemporary physiological models of the human circadian oscillator. This article is protected by copyright. All rights reserved.
      PubDate: 2014-06-24T08:30:20.944453-05:
      DOI: 10.1111/php.12282
  • New Advances in Protection Against Solar Ultraviolet Radiation in Textiles
           for Summer Clothing
    • Authors: José Aguilera; María Victoria Gálvez, Cristina Sánchez-Roldán, Enrique Herrera-Ceballos
      First page: 1199
      Abstract: Clothing is considered one of the most important tools for photoprotection against harmful solar ultraviolet radiation (UVR). The standard for sun‐protective clothing is based on erythema despite other biological effects of UVR on the skin. We analyzed the potential protection against UVR in fabrics destined for summer clothing based on several action spectra. We examined 50 garments classified by type of fabric composition, structure of the fiber yarn and color. The ultraviolet protection factor was calculated based on fabric ultraviolet transmittance corrected for erythema according to the EU standard E‐13758 as well as the UVA transmittance of fabrics. UVR protection was also analyzed in base of different action spectra as for previtamin D3, nonmelanoma skin cancer, photoimmunosuppression and photoaging. Most knitted fabrics used for sports T‐shirts offered excellent ratings for ultraviolet protection while normal shirts showed very low ratings, particularly against photoaging. The cover is the most influential variable in fabric photoprotection, having an exponential relationship with the UPF. The relation between cover and UVA protection was linearly negative. Information about ultraviolet protection in textiles used for summer clothing should be included in labeling as some types of fabrics, especially those used for shirts, offer very low UVR protection. Microscopic analysis of different types of fabrics used in traditional summer clothing shows differences in structure, yarn and composition. Five different types of fabric were classified as follows: linen shirts (A), polyester shirts (B), T‐shirts (C), polo T‐shirts (D) and the latest generation of sport textiles (E), which leads to different abilities of light transmission, namely cover. Ultraviolet protection factor, based on the potential of protection against the erythematic fraction of UV radiation increases exponentially as the fabric cover does.
      PubDate: 2014-06-18T06:53:00.341326-05:
      DOI: 10.1111/php.12292
  • Biochemical Composition and Antioxidant Properties of Lavandula
           angustifolia Miller Essential Oil are Shielded by Propolis Against UV
    • Authors: Angelo Gismondi; Lorena Canuti, Marta Grispo, Antonella Canini
      Pages: 1214 - 1214
      PubDate: 2014-09-05T14:14:19.642582-05:
      DOI: 10.1111/php.12339
  • Effect of Light on Expression of Clock Genes in Xenopus laevis
    • Authors: Maria Nathália Moraes; Maristela Poletini, Bruno Cesar Ribeiro Ramos, Leonardo Henrique Ribeiro Graciani Lima, Ana Maria Castrucci
      Pages: n/a - n/a
      Abstract: Light‐dark cycles are considered important cues to entrain biological clocks. A feedback loop of clock gene transcription and translation is the molecular basis underlying the mechanism of both central and peripheral clocks. Xenopus laevis embryonic melanophores respond to light with melanin granule dispersion, response possibly mediated by the photopigment melanopsin. In order to test whether light modulates clock gene expression in Xenopus melanophores, we used qPCR to evaluate the relative mRNA levels of Per1, Per2, Clock and Bmal1 in cultured melanophores exposed to light‐dark (LD) cycle or constant darkness (DD). LD cycles elicited temporal changes in the expression of Per1, Per2 and Bmal1. A 10‐min pulse of blue light was able to increase the expression of Per1 and Per2. Red light had no effect on the expression of these clock genes. These data suggest the participation of a blue‐wavelength sensitive pigment in the light‐dark cycle‐mediated oscillation of the endogenous clock. Our results add an important contribution to the emerging field of peripheral clocks, which in non‐mammalian vertebrates have been mostly studied in Drosophila and Danio rerio. Within this context, we show that Xenopus laevis melanophores, which have already led to melanopsin discovery, represent an ideal model to understanding circadian rhythms. This article is protected by copyright. All rights reserved.
      PubDate: 2013-12-26T07:09:26.462616-05:
      DOI: 10.1111/j.1751-1097.2013.12230.x
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