Authors:Vishakha Singh, Amit Khurana, Umashanker Navik, Prince Allawadhi, Kala Kumar Bharani, Ralf Weiskirchen First page: 15 Abstract: Apoptosis is an evolutionarily conserved sequential process of cell death to maintain a homeostatic balance between cell formation and cell death. It is a vital process for normal eukaryotic development as it contributes to the renewal of cells and tissues. Further, it plays a crucial role in the elimination of unnecessary cells through phagocytosis and prevents undesirable immune responses. Apoptosis is regulated by a complex signaling mechanism, which is driven by interactions among several protein families such as caspases, inhibitors of apoptosis proteins, B-cell lymphoma 2 (BCL-2) family proteins, and several other proteases such as perforins and granzyme. The signaling pathway consists of both pro-apoptotic and pro-survival members, which stabilize the selection of cellular survival or death. However, any aberration in this pathway can lead to abnormal cell proliferation, ultimately leading to the development of cancer, autoimmune disorders, etc. This review aims to elaborate on apoptotic signaling pathways and mechanisms, interacting members involved in signaling, and how apoptosis is associated with carcinogenesis, along with insights into targeting apoptosis for disease resolution. Citation: Sci PubDate: 2022-04-06 DOI: 10.3390/sci4020015 Issue No:Vol. 4, No. 2 (2022)
Authors:Tugce Kalkan, Florin F. Nichita, Tahsin Oner, Ibrahim Senturk, Mehmet Terziler First page: 16 Abstract: The current paper explores the potential of the areas between mathematics and poetry. We will first recall some definitions and results that are needed to construct solutions of the Yang–Baxter equation. A new duality principle is presented and Boolean coalgebras are introduced. A section on poetry dedicated to the Yang–Baxter equation is presented, and a discussion on a poem related to a mathematical formula follows. The final section presents our conclusions and further information on these topics. Citation: Sci PubDate: 2022-04-11 DOI: 10.3390/sci4020016 Issue No:Vol. 4, No. 2 (2022)
Authors:Sławomir J. Grabowski First page: 17 Abstract: Complexes linked by various interactions are analysed in this study. They are characterized by the tetrahedral configuration of the Lewis acid centre. Interactions, being a subject of this study, are classified as σ-hole bonds, such as the halogen, chalcogen, pnicogen, and tetrel bonds. In the case of strong interactions, the tetrahedral configuration of the Lewis acid centre changes into the trigonal bipyramid configuration. This change is in line with the Valence-Shell Electron-Pair Repulsion model, VSEPR, and this is supported here by the results of high-level ab initio calculations. The theoretical results concerning the geometries are supported mainly by the Natural Bond Orbital, NBO, method. Citation: Sci PubDate: 2022-04-19 DOI: 10.3390/sci4020017 Issue No:Vol. 4, No. 2 (2022)
Authors:Giuseppe Cantisani, Giulia Del Serrone, Paolo Peluso First page: 18 Abstract: In recent years, innovative progress in information and communication technology (ICT) has introduced new sources for traffic data collection and analysis. On-board sensors like GPS-GPRS boxes, generally installed for insurance purposes, communicate information from circulating vehicles to data centers. Geographic location, date and time, vehicles’ speed and direction, are systematically transmitted and stored as Historical Car Data (HCD) from probe vehicles in the traffic stream. These databases provide a good opportunity to analyze the vehicles’ motion both in the temporal and spatial domains. The aim of this study is to pay attention to the reliability of this kind of data gathering. Since instrumented vehicles account for a small percentage of the entire vehicle fleet, it is important to understand if they can be considered as a sample representative of the whole population. The paper presents a comparison of speed data obtained from HCD with the ones recorded by inductive-loop detectors and microwave radar sensors; the performed analysis required the definition of specific methodologies and procedures. The obtained results show a high correspondence between the two sets of data. Therefore, HCD can be proposed for the detailed monitoring of, and studies on, the operating conditions of mobility along road networks. Citation: Sci PubDate: 2022-04-21 DOI: 10.3390/sci4020018 Issue No:Vol. 4, No. 2 (2022)
Authors:Florin-Felix Nichita First page: 19 Abstract: The Special Issue “Mathematics and Poetry, with a View towards Machine Learning”, started with three guiding questions from the guest editor:What are the similarities (and differences) between mathematical problems and poetic works [...] Citation: Sci PubDate: 2022-05-12 DOI: 10.3390/sci4020019 Issue No:Vol. 4, No. 2 (2022)
Authors:Gregory P. Conners First page: 20 Abstract: Background: Management of the child who has swallowed a foreign body should be guided by the risk of complication. Objective of the Review: This review discusses the patient and foreign body characteristics most likely to be associated with complications. Discussion: Most swallowed foreign bodies will pass through the GI tract without complication. Children with pre-existing GI tract abnormalities of any sort, or those who swallow higher-risk foreign bodies, are at higher risk. Higher-risk foreign bodies include long, sharp, or pointed objects, button batteries, and small magnets. Nearly any child who presents to an Emergency Department or other acute care setting after foreign body ingestion should undergo plain radiography; other forms of imaging may also be appropriate. Primary care providers may opt for an initial observation period when there is lower risk of complication. Esophageal button batteries should be emergently removed; other esophageal objects should be promptly removed or, if low risk, allowed a brief period to pass spontaneously. Most lower GI tract foreign bodies will pass spontaneously. Prevention, while not always possible, is preferable to management of foreign body ingestion. Conclusions: Management strategies for children who have swallowed foreign bodies can be optimized by considering relevant patient and foreign body factors, and how they contribute to the risk of complication. Citation: Sci PubDate: 2022-05-17 DOI: 10.3390/sci4020020 Issue No:Vol. 4, No. 2 (2022)
Authors:Konstantina Tsami, Christina Barda, George Ladopoulos, Nikos Asoutis Didaras, Maria-Eleni Grafakou, Jörg Heilmann, Dimitris Mossialos, Michail Christou Rallis, Helen Skaltsa First page: 21 Abstract: Within the large family of Dioscoreaceae, Dioscorea communis (L.) Caddick & Wilkin (syn. Tamus communis L.) is considered among the four most widespread representatives in Europe, and it is commonly known under the name black bryony or bryonia. To date, reports have revealed several chemical components from the leaves and tubers of this plant. Nevertheless, an extensive phytochemical investigation has not been performed on its berry juice. In the present study, metabolite profiling procedures, using LC-MS, GC-MS, and NMR approaches, were applied to investigate the chemical profile of the D. communis berries. This work reveals the presence of several metabolites belonging to different phytochemical groups, such as fatty acid esters, alkylamides, phenolic derivatives, and organic acids, with lactic acid being predominant. In parallel, based on orally transmitted traditional uses, the initial extract and selected fractions were tested in vitro for their antibacterial effects and exhibited good activity against two bacterial strains related to skin infections: methicillin-resistant Staphylococcus aureus and Cutibacterium acnes. The MIC and MBC values of the extract were determined at 1.56% w/v against both bacteria. The results of this study provide important information on the chemical characterization of the D. communis berry juice, unveiling the presence of 71 metabolites, which might contribute to and further explain its specific antibacterial activity and its occasional toxicity. Citation: Sci PubDate: 2022-05-18 DOI: 10.3390/sci4020021 Issue No:Vol. 4, No. 2 (2022)
Authors:Kiernan Foster, Brooke Hillman, Vahab Rajaei, Kimsorn Seng, Sarah Maurer First page: 22 Abstract: One of the challenges in understanding chemical evolution is the large number of starting organics and environments that were plausible on early Earth. Starting with realistic organic mixtures and using chemical analyses that are not biologically biased, understanding the interplay between organic composition and environment can be approached using statistical analysis. In this work, a mixture of 73 organics was cycled through dehydrating conditions five times, considering environmental parameters of pH, salinity, and rehydration solution. Products were analyzed by HPLC, amide and ester assays, and phosphatase and esterase assays. While all environmental factors were found to influence chemical evolution, salinity was found to play a large role in the evolution of these mixtures, with samples diverging at very high sea salt concentrations. This framework should be expanded and formalized to improve our understanding of abiogenesis. Citation: Sci PubDate: 2022-05-27 DOI: 10.3390/sci4020022 Issue No:Vol. 4, No. 2 (2022)
Authors:Ross Greenwood, Anthony Aguirre First page: 23 Abstract: Everlasting inflation has far-reaching implications for cosmology and the standing of self-localizing inferences made by observers, which have been subjects of renewed interest in light of the growing acceptance of theory landscapes and the attendant anthropic arguments. Under what assumptions and to what extent does inflation generically produce an eternal “multiverse,” without fine-tuning with respect to measures over the space of inflationary cosmologies driven by a single minimally coupled scalar field' We address this and related questions with numerical simulations of inflationary dynamics across populations of randomly generated inflation models, instantiating a few particular simply-defined measures. Citation: Sci PubDate: 2022-05-31 DOI: 10.3390/sci4020023 Issue No:Vol. 4, No. 2 (2022)
Authors:Halina Szatylowicz, Paweł A. Wieczorkiewicz, Tadeusz M. Krygowski First page: 24 Abstract: Aromaticity, a very important term in organic chemistry, has never been defined unambiguously. Various ways to describe it come from different phenomena that have been experimentally observed. The most important examples related to some theoretical concepts are presented here. Citation: Sci PubDate: 2022-06-09 DOI: 10.3390/sci4020024 Issue No:Vol. 4, No. 2 (2022)
Authors:Xiaodan Zhang, Jun Chang, Xiaohua Yao, Jingru Wang, Jiatian Zhang, Yang Yang, Shuiping Yang, Kailiang Wang, Huadong Ren First page: 25 Abstract: As woody oil crop, pecan [Carya illinoinensis (Wangenh.) K. Koch] may be a solution to the shortage of edible oil in the future. In this study, fruit traits, kernel nutrition and fatty acid composition of 10 pecan varieties were determined to assess the potential of pecans for exploitation as edible oil, as well as to further screen varieties that could be used as edible oil resources and to understand their development prospects for cultivation in mountainous hills. The study showed that all the fruit trait indicators measured, including green-fruit weight (mean 28.47 g), nut weight (10.33 g), kernel weight (5.25 g), nut percentage (36.83%) and kernel percentage (50.50%), showed highly significant differences among the 10 varieties. Among the main nutritional indicators of the kernels, the crude fat content was stable (mean 70.01%) with non-significant differences, while protein (67.50 mg·g−1), soluble sugar (10.7 mg·g−1) and tannin (6.07 mg·g−1) showed highly significant differences between varieties. The oil percentage of nuts (kernel percentage * crude fat) averaged 35.36%, with highly significant differences between varieties. The fatty acid composition was dominated by unsaturated fatty acids (mean 91.82%), with unsaturated fatty acids being 11.24 times more abundant than saturated fatty acids. Among the monounsaturated fatty acids, oleic acid was the highest (mean 70.02%), with highly significant differences between varieties, followed by cis-11-eicosanoic acid (0.25%), with non-significant differences between varieties; among the polyunsaturated fatty acids, linoleic acid was the highest (19.58%), followed by linolenic acid (0.97%), both of which showed highly significant differences between varieties; monounsaturated fatty acids were 2.42 times more abundant than polyunsaturated fatty acids. Compared to other oilseed crops, pecan has the potential to produce “nutritious, healthy and stable” edible oil, while its wide habitat and good productivity benefits offer broad prospects for development in the hills and mountains of subtropical China. Citation: Sci PubDate: 2022-06-10 DOI: 10.3390/sci4020025 Issue No:Vol. 4, No. 2 (2022)
Authors:Phillippa Zambas-Adams, Kevin C. Honeychurch First page: 1 Abstract: Understanding of the levels of psychoactive drugs in air is important for assessing both occupational and environmental exposure. Intelligence on the usage and manufacture of illegal drugs can also be gained. Environmental analysis and determination of air quality has recently expanded from its traditional focus to new pollutant categories that include illicit and psychoactive drugs. This is attributed to a greater part on the development of new, advanced techniques, such as liquid chromatography/mass spectrometry (LC/MS), allowing for the trace determination of such compounds down to the parts-per-trillion (ng/L) levels generally reported in air. Studies have also investigated the effects of firsthand and secondhand smoking of drugs, such as cocaine, cannabis and opium. Generally, these have shown secondhand smoke effects to be limited, apart from in the case of opium. Some studies have highlighted ill effects resulting through the exposure of vapors and dusts from the storage of drugs, but this has been shown to result from mould and other fungal contaminates. Investigations into the possible occupational exposures resulting from the use of anesthetic drugs in surgery and accident and emergency have focused on nitrous oxide, sevoflurane, methoxyflurane, isoflurane, propofol and fentanyl. This review focuses on developments and applications for the determination of psychoactive drugs in air. Citation: Sci PubDate: 2022-01-01 DOI: 10.3390/sci4010001 Issue No:Vol. 4, No. 1 (2022)
Authors:Jiede Wu, Yikang Sun, Rung-Tai Lin First page: 2 Abstract: A simplified approach was used to determine if “Less is More” is still a trend in comics’ Peking opera characters. There were 225 website volunteers who took part in the study. Via a questionnaire survey and analysis, this study explored the feasibility of “simplification” in comedy. The results indicate that the proposed “simplifying” approach can be applied to the creation of dramatic characters, but the scale of simplification must be adjusted flexibly to suit different subjects. For audiences, there is not much recognition and sympathy for the works that are simplified in the extreme and the current symbolization. The simplification used in this study is merely the first step in testing the usefulness of simplification as an approach. It is used as a means of understanding the cognition of the audience to accept the simple features of Peking opera characters. In subsequent studies, the proposed “simplified” approach is necessary to adapt and improve with a view to practical application. It also requires an in-depth analysis of the cognitive differences of the different participants according to the cognitive and communication theories of artistic creation. Citation: Sci PubDate: 2022-01-07 DOI: 10.3390/sci4010002 Issue No:Vol. 4, No. 1 (2022)
Authors:Steinar Valsson, Ognjen Arandjelović First page: 3 Abstract: With the increase in the availability of annotated X-ray image data, there has been an accompanying and consequent increase in research on machine-learning-based, and ion particular deep-learning-based, X-ray image analysis. A major problem with this body of work lies in how newly proposed algorithms are evaluated. Usually, comparative analysis is reduced to the presentation of a single metric, often the area under the receiver operating characteristic curve (AUROC), which does not provide much clinical value or insight and thus fails to communicate the applicability of proposed models. In the present paper, we address this limitation of previous work by presenting a thorough analysis of a state-of-the-art learning approach and hence illuminate various weaknesses of similar algorithms in the literature, which have not yet been fully acknowledged and appreciated. Our analysis was performed on the ChestX-ray14 dataset, which has 14 lung disease labels and metainfo such as patient age, gender, and the relative X-ray direction. We examined the diagnostic significance of different metrics used in the literature including those proposed by the International Medical Device Regulators Forum, and present the qualitative assessment of the spatial information learned by the model. We show that models that have very similar AUROCs can exhibit widely differing clinical applicability. As a result, our work demonstrates the importance of detailed reporting and analysis of the performance of machine-learning approaches in this field, which is crucial both for progress in the field and the adoption of such models in practice. Citation: Sci PubDate: 2022-01-16 DOI: 10.3390/sci4010003 Issue No:Vol. 4, No. 1 (2022)
Authors:Tímea Mosolygó, Krisztián Laczi, Gabriella Spengler, Katalin Burián First page: 4 Abstract: From gene expression studies to identifying microbes, quantitative polymerase chain reaction (qPCR) is widely used in research and medical diagnostics. In transmittable diseases like the Ebola outbreak in West Africa (2014–2016), or the present SARS-CoV2 pandemic qPCR plays a key role in the detection of infected patients. Although the technique itself is decades old with reliable approaches (e.g., TaqMan assay) in the diagnosis of pathogens many people showed distrust in it during the SARS-CoV2 outbreak. This came mainly from not understanding or misunderstanding the principles of qPCR. This situation motivated us to design a simple laboratory practical class, in which students have opportunities to understand the underlying principles of qPCR and its advantages in microbiological diagnosis. Moreover, during the exercise, students can develop skills such as handling experimental assays, and the ability to solve problems, discuss their observations. Finally, this activity brings them closer to the clinical practice and they can see the impact of the science on real life. The class is addressed to undergraduate students of biological sciences. Citation: Sci PubDate: 2022-01-17 DOI: 10.3390/sci4010004 Issue No:Vol. 4, No. 1 (2022)
Authors:Najlaa Hamdi, Souad Chaouch, Ivan da Silva, Mohamed Ezahri, Mohammed Lachkar, Rama Alhasan, Ahmad Yaman Abdin, Claus Jacob, Brahim El Bali First page: 5 Abstract: A novel hybrid cobalt phosphite, (H2DAB)[Co(H2PO3)4] 2H2O, was synthesized by using a slow evaporation method in the presence of cobalt nitrate, phosphorous acid, and 1,4-diaminobutane (DAB = 1,4-diaminobutane) as a structure-directing agent. Single-crystal X-ray diffraction analysis showed that the compound crystallizes in the triclinic system (space group P-1(n.2)) with the following unit cell parameters (Å, °) a = 5.4814 (3), b = 7.5515 (4), c = 10.8548 (6), α = 88.001 (4), β = 88.707 (5), γ = 85.126 (5), and V = 447.33 (4) Å3. The crystal structure is built up from corner-sharing [CoO6] octahedra, forming chains parallel to [001], which are interconnected by H2PO3− pseudo-tetrahedral units. The diprotonated cations, residing between the parallel chains, interact with the inorganic moiety via hydrogen bonds, thus leading to the formation of the 3D crystal structure. The Fourier transform infrared spectrum showed characteristic bands corresponding to the phosphite group and the organic amine. The thermal behavior of the compound mainly consisted of the loss of its organic moiety and the water molecules. The biological tests exhibited significant activity against Candida albicans and Escherichia coli strains at different concentrations, while less inhibitory activity was pronounced against Staphylococcus epidermidis and Saccharomyces cerevisiae, and in the case of multi-cellular organisms, no activity against the nematode model Steinernema feltiae was detected. Citation: Sci PubDate: 2022-02-08 DOI: 10.3390/sci4010005 Issue No:Vol. 4, No. 1 (2022)
Authors:M. Merced Montero-Campillo, Otilia Mó, Manuel Yáñez First page: 7 Abstract: The stability of malonaldehyde is governed by intramolecular hydrogen bonds (IMHBs) as well as in malonaldehyde-like systems where oxygen is replaced by N or S at any of the basic sites. As beryllium bonds have been shown to strongly cooperate with hydrogen bonds, this work explores at the high level ab initio G4 level of theory the effect of including this non-covalent interaction in the system through its association with BeF2. Although malonaldehyde follows the expected trends, where the formation of a pseudocyclic form is favored also when IMHB and Be bonds are present, the subtle balance between both non-covalent interactions leads to some surprising results when other heteroatoms are involved, to the point that interaction energies can be much larger than expected or even cyclization is not favored. A complete analysis using different computational tools gives an answer to those cases escaping the predictable trends. Citation: Sci PubDate: 2022-02-13 DOI: 10.3390/sci4010007 Issue No:Vol. 4, No. 1 (2022)
Authors:Saïd Abdellati, Jolein Laumen, Natalia Gonzalez, Sheeba S. Manoharan-Basil, Christophe Van Dijck, Irith De Baetselier, Delphine Martiny, Tessa de Block, Chris Kenyon First page: 8 Abstract: Antibiotic-sparing treatments are required to prevent the further emergence of antimicrobial resistance in Neisseria gonorrhoeae. Commensal Neisseria species have previously been found to inhibit the growth of pathogenic Neisseria species. For example, a previous study found that three out of five historical isolates of Neisseria mucosa could inhibit the growth of N. gonorrhoeae. In this study, we used agar overlay assays to assess if 24 circulating and historical isolates of Neisseria mucosa could inhibit the growth of 28 circulating and historical isolates of N. gonorrhoeae. Although pitting around each colony of N. mucosa created an optical illusion of decreased growth of N. gonorrhoeae, we found no evidence of inhibition (n = 24). In contrast, positive controls of Streptococcus pneumoniae and Escherichia coli demonstrated a strong inhibitory effect against the growth of N. gonorrhoeae. Citation: Sci PubDate: 2022-02-23 DOI: 10.3390/sci4010008 Issue No:Vol. 4, No. 1 (2022)
Authors:Rubén D. Parra First page: 9 Abstract: Cyclic dimers and trimers of tetra-substituted benzenes, ((HOOC)2-C6H2-(NHI)2), are selected as convenient model systems for investigating NI…O=C halogen bond strength and cooperativity. The four substituents in benzene are chosen so that two of them act as halogen bond acceptors (COOH) and two act as halogen bond donors (NHI), as shown in the graphical abstract below. The potential for metal ion binding by each of the halogen-bonded aggregates is also investigated using the monoatomic sodium ion, Na+. Density functional theory calculations performed using the wB97XD functional and the DGDZVP basis set confirmed the ability of halogen bonding to drive the formation of the cyclic dimers and trimers of the model system chosen for this study. Evidence of halogen bond cooperativity is seen, for example, in a 9% shortening of each NI…O=C halogen bond distance with a corresponding 53% increase in the respective critical point density value, ρNI…O=C. Cooperativity also results in a 36% increase in the magnitude of the complexation energy per halogen-bond of the trimer relative to that of the dimer. The results of this study confirm the potential for binding a single Na+ ion by either the dimer or the trimer through their respective halogen-bond networks. Binding of two metal ions was shown to be possible by the dimer. Likewise, the trimer was also found to bind three metal ions. Lastly, the overall structure of the halogen-bonded dimer or trimer endured after complexation of the Na+ ions. Citation: Sci PubDate: 2022-02-25 DOI: 10.3390/sci4010009 Issue No:Vol. 4, No. 1 (2022)
Authors:Ahmad Yaman Abdin, Claus Jacob First page: 10 Abstract: Sci (ISSN 2413-4155) is an international, open-access journal that covers most fields of scientific research. It has set out to challenge the conventional single- and double-blind peer review processes by adopting a post-publication public peer review (P4R) model. The model faced some difficulties with indexing and archiving services, prolongated the peer review process and its transparency received some opposition. It was therefore necessary to revisit the P4R model and modify it, resulting in the hybrid model (P4R hybrid) which is implemented in Sci today. Sci remains open to the whole scientific community as an inclusive and multidisciplinary scientific journal. In this context, we present you with six valuable contributions to the first Special Issue of Feature Papers Editors Collection 2020. The topics of the contributions address relevant and compelling issues ranging from data protection, material science, COVID-19 to the environment and climate change. Citation: Sci PubDate: 2022-03-07 DOI: 10.3390/sci4010010 Issue No:Vol. 4, No. 1 (2022)
Authors:Marinella Difonzo, Louise Fliedel, Nathalie Mignet, Karine Andrieux, Khair Alhareth First page: 11 Abstract: Pregnancy is a delicate state, during which timely investigation of possible physiological anomalies is essential to reduce the risk of maternal and fetal complications. Medical imaging encompasses different technologies to image the human body for the diagnosis, course of treatment management, and follow-up of diseases. Ultrasound (US) is currently the imaging system of choice for pregnant patients. However, sonographic evaluations can be non-effective or give ambiguous results. Therefore, magnetic resonance imaging (MRI), due to its excellent tissue penetration, the possibility of acquisition of three-dimensional anatomical information, and its high spatial resolution, is considered a valid diagnostical alternative. Nevertheless, currently employed contrast agents to improve the MRI image quality are harmful to the fetus. Because of their ability to cross the placenta, their use on pregnant patients is avoided. This review will firstly recapitulate the most common non-obstetrical, obstetrical, and fetal indications for magnetic resonance imaging on pregnant women. Fetal safety risks, due to the use of strong magnetic fields and exogenous contrast agents, will be presented. Then, possible advantages of nanostructured contrast agents compared to current molecular ones are explored. Nanosystems’ characteristics affecting contrast efficiency, and their potential for improving contrast-enhanced MRI’s safety in pregnant women, are discussed. Lastly, promising examples of nanoparticles as safer alternatives to current MRI contrast agents in pregnancy are discussed. Citation: Sci PubDate: 2022-03-15 DOI: 10.3390/sci4010011 Issue No:Vol. 4, No. 1 (2022)
Authors:Azhagu Raj Ramakrishnan, Krishna Kumar, Palavesam Arunachalam, Muthupandi Sankar, Prathap Selvaraj, Sohan Jheeta First page: 12 Abstract: Ultraviolet (UV) radiation is a part of the spectrum of electromagnetic radiation emitted by the Sun. The present study was conducted to examine the deleterious effects of UV radiation on the stratum corneum of fish—namely, Glossogobius giuris. In this study, healthy living specimens of G. giuris species weighing (1.20 g) and length (4.06 cm) were collected from Thandavarayankulam lake, Srivaikuntam Taluk, Thoothukudi District, Tamil Nadu. They were transported to the laboratory in well-aerated containers. During the experiment, the fish G. giuris (n = 6) was introduced into the UV Chamber (UVA and UVB) for one hour. After that, experimental fishes were collected from the UV Chamber were dissected for histological and biochemical studies using standard methodology. The short-term exposure of UVA and UVB rays on freshwater G. giuris muscle tissue showed marked degeneration of the epithelium, the disappearance of striations, thickened septal wall, broken fibre, and the disappearance of striation, followed by branchial arterial rupture. It was also determined that carbohydrate, protein, and lipid contents of the muscle tissue were significantly reduced. This study confirmed the destructive effects of UV radiation on the stratum corneum of fish G. giuris. The ultrastructural and biochemical changes occur depending largely on the energy of the UV rays; in this case, the UVB radiation, with higher destructive energy (4.4 eV), had a greater detrimental effect on the muscles of G. giuris than UVA, with its energy level of 3.9 eV. Citation: Sci PubDate: 2022-03-15 DOI: 10.3390/sci4010012 Issue No:Vol. 4, No. 1 (2022)
Authors:Shusaku Ikeyama, Hiroyasu Tabe First page: 13 Abstract: The development of methods for converting nitrogen oxides in water into valuable resources such as ammonia and hydrazine has been given some attention. By utilizing the nitrite-reducing catalytic activity of nitrite reductase (NiR), nitrite in water can be converted into ammonium. However, there are few reports in the research that synthesized ammonium from nitrite using nitrite reductase. Therefore, we aimed to investigate the effect of temperature on the nitrite-reducing catalytic activity of NiR from spinach in the presence of one-electron reduced riboflavin by kinetic analysis to find the optimum temperature conditions. The results of this study showed that the reaction temperature does not need to be higher than 296.15 K in order to improve the efficiency of ammonium production from nitrite using NiR. Citation: Sci PubDate: 2022-03-15 DOI: 10.3390/sci4010013 Issue No:Vol. 4, No. 1 (2022)
Authors:Maria-Elena Ignatiadou, Maria Kostaki, Zahia Kabouche, Paschalina Chatzopoulou, Michail Christou Rallis, Anastasia Karioti First page: 14 Abstract: The present study aimed to investigate the chemical profile and the protective activity on fibroblasts of two Matricaria species: M. pubescens, which grows wild in Algeria, and M. recutita, which is cultivated in Greece. A comparative phytochemical investigation using High-Performance Liquid Chromatography, coupled with Photodiode Array Detection and Mass Spectrometry (HPLC–PDA–MS) combined with Nuclear Magnetic Resonance (NMR), was performed for the identification of the main constituents in the flowerheads of these medicinal plants. In M. pubescens more than 25 compounds were identified and/or isolated; among them are quercetagenin-3-O-glucopyranoside, reported for the first time in Matricaria sp., and two polyamines previously reported in other Asteraceae species. In M. recutita, which is the officially recognized species in Europe, 19 constituents were identified. To minimize time analysis, the structure elucidation was based on a multi-analytical approach directly on subfractions. Two representative polar extracts from each species were characterized chemically and further screened for their protective effects on 3T3 fibroblasts. The cells were exposed to a mild toxic dose of UVA light (6 J/cm2), in the presence of different concentrations of the extracts. Both M. recutita and M. pubescens extracts were effective. The methanolic extract was the best protective agent at lower concentrations (0.1 to 10 μg/mL), and hydromethanolic was best at higher ones (100–200 μg/mL). M. recutita exhibited the most enhanced cell viability in relation to those not exposed to UV control; it ranged from of 28 to 49% higher viability, depending on the dose, leading to the conclusion that the latter seems to exhibit potent cytoprotective activity and significant regeneration activity. Citation: Sci PubDate: 2022-03-18 DOI: 10.3390/sci4010014 Issue No:Vol. 4, No. 1 (2022)