Subjects -> MEDICAL SCIENCES (Total: 8359 journals)
    - ALLERGOLOGY AND IMMUNOLOGY (210 journals)
    - ANAESTHESIOLOGY (119 journals)
    - CARDIOVASCULAR DISEASES (329 journals)
    - CHIROPRACTIC, HOMEOPATHY, OSTEOPATHY (21 journals)
    - COMMUNICABLE DISEASES, EPIDEMIOLOGY (228 journals)
    - DENTISTRY (288 journals)
    - DERMATOLOGY AND VENEREOLOGY (162 journals)
    - EMERGENCY AND INTENSIVE CRITICAL CARE (119 journals)
    - ENDOCRINOLOGY (148 journals)
    - FORENSIC SCIENCES (41 journals)
    - GASTROENTEROLOGY AND HEPATOLOGY (182 journals)
    - GERONTOLOGY AND GERIATRICS (132 journals)
    - HEMATOLOGY (153 journals)
    - HYPNOSIS (4 journals)
    - INTERNAL MEDICINE (164 journals)
    - LABORATORY AND EXPERIMENTAL MEDICINE (98 journals)
    - MEDICAL GENETICS (58 journals)
    - MEDICAL SCIENCES (2268 journals)
    - NURSES AND NURSING (356 journals)
    - OBSTETRICS AND GYNECOLOGY (202 journals)
    - ONCOLOGY (377 journals)
    - OPHTHALMOLOGY AND OPTOMETRY (136 journals)
    - ORTHOPEDICS AND TRAUMATOLOGY (164 journals)
    - OTORHINOLARYNGOLOGY (80 journals)
    - PATHOLOGY (96 journals)
    - PEDIATRICS (270 journals)
    - PHYSICAL MEDICINE AND REHABILITATION (152 journals)
    - PSYCHIATRY AND NEUROLOGY (813 journals)
    - RADIOLOGY AND NUCLEAR MEDICINE (190 journals)
    - RESPIRATORY DISEASES (102 journals)
    - RHEUMATOLOGY (76 journals)
    - SPORTS MEDICINE (78 journals)
    - SURGERY (393 journals)
    - UROLOGY, NEPHROLOGY AND ANDROLOGY (150 journals)

MEDICAL SCIENCES (2268 journals)            First | 1 2 3 4 5 6 7 8 | Last

Showing 201 - 400 of 3562 Journals sorted alphabetically
Atti della Accademia Peloritana dei Pericolanti - Classe di Scienze Medico-Biologiche     Open Access  
Audiology - Communication Research     Open Access   (Followers: 10)
Auris Nasus Larynx     Full-text available via subscription  
Australasian Journal of Ultrasound in Medicine (AJUM)     Hybrid Journal  
Australian Coeliac     Full-text available via subscription   (Followers: 1)
Australian Family Physician     Full-text available via subscription   (Followers: 3)
Australian Journal of Medical Science     Full-text available via subscription   (Followers: 2)
Autopsy and Case Reports     Open Access  
Avicenna     Open Access   (Followers: 3)
Avicenna Journal of Clinical Medicine     Open Access  
Avicenna Journal of Medicine     Open Access   (Followers: 1)
Bangabandhu Sheikh Mujib Medical University Journal     Open Access   (Followers: 1)
Bangladesh Journal of Anatomy     Open Access   (Followers: 2)
Bangladesh Journal of Bioethics     Open Access  
Bangladesh Journal of Medical Biochemistry     Open Access   (Followers: 4)
Bangladesh Journal of Medical Education     Open Access   (Followers: 2)
Bangladesh Journal of Medical Microbiology     Open Access   (Followers: 4)
Bangladesh Journal of Medical Physics     Open Access   (Followers: 1)
Bangladesh Journal of Medical Science     Open Access  
Bangladesh Journal of Medicine     Open Access   (Followers: 1)
Bangladesh Journal of Physiology and Pharmacology     Open Access  
Bangladesh Journal of Scientific Research     Open Access   (Followers: 1)
Bangladesh Medical Journal     Open Access  
Bangladesh Medical Journal Khulna     Open Access  
Basal Ganglia     Hybrid Journal  
Basic Sciences of Medicine     Open Access   (Followers: 2)
Batı Karadeniz Tıp Dergisi / Medical Journal of Western Black Sea     Open Access  
Baylor University Medical Center Proceedings     Hybrid Journal  
BBA Clinical     Open Access  
BC Medical Journal     Free  
Benha Medical Journal     Open Access  
Beni-Suef University Journal of Basic and Applied Sciences     Open Access   (Followers: 4)
Bijblijven     Hybrid Journal  
Bijzijn     Hybrid Journal   (Followers: 1)
Bijzijn XL     Hybrid Journal  
Bio-Algorithms and Med-Systems     Hybrid Journal   (Followers: 2)
BioDiscovery     Open Access   (Followers: 2)
Bioelectromagnetics     Hybrid Journal   (Followers: 2)
Bioelectronic Medicine     Open Access   (Followers: 1)
Bioengineering & Translational Medicine     Open Access  
Bioethics     Hybrid Journal   (Followers: 17)
Bioethics Research Notes     Full-text available via subscription   (Followers: 14)
Biologics in Therapy     Open Access  
Biology of Sex Differences     Open Access   (Followers: 2)
Biomarker Research     Open Access   (Followers: 3)
Biomarkers in Medicine     Hybrid Journal   (Followers: 2)
BioMed Research International     Open Access   (Followers: 4)
Biomédica     Open Access  
Biomedical & Life Sciences Collection     Full-text available via subscription   (Followers: 3)
Biomedical and Biotechnology Research Journal     Open Access   (Followers: 1)
Biomedical Engineering     Hybrid Journal   (Followers: 17)
Biomedical Engineering and Computational Biology     Open Access   (Followers: 13)
Biomedical Engineering Letters     Hybrid Journal   (Followers: 6)
Biomedical Engineering Research     Open Access   (Followers: 7)
Biomedical Informatics Insights     Open Access   (Followers: 8)
Biomedical Journal     Open Access   (Followers: 3)
Biomedical Materials     Hybrid Journal   (Followers: 7)
Biomedical Microdevices     Hybrid Journal   (Followers: 8)
Biomedical Optics Express     Open Access   (Followers: 6)
Biomedical Photonics     Open Access  
Biomedical Reports     Full-text available via subscription  
Biomedical Research Reports     Full-text available via subscription   (Followers: 2)
Biomedical Safety & Standards     Full-text available via subscription   (Followers: 8)
Biomedical Science and Engineering     Open Access   (Followers: 7)
BioMedicine     Open Access  
Biomedicine Hub     Open Access  
Biomedicines     Open Access   (Followers: 1)
Biomedika     Open Access  
Biomolecular and Health Science Journal     Open Access   (Followers: 1)
Biophysics Reports     Open Access  
BioPsychoSocial Medicine     Open Access   (Followers: 8)
Biosalud     Open Access   (Followers: 1)
Biostatistics & Epidemiology     Hybrid Journal   (Followers: 1)
Birat Journal of Health Sciences     Open Access  
BIRDEM Medical Journal     Open Access   (Followers: 1)
Birth Defects Research     Hybrid Journal  
Birth Defects Research Part A : Clinical and Molecular Teratology     Hybrid Journal   (Followers: 3)
Birth Defects Research Part C : Embryo Today : Reviews     Hybrid Journal  
BJR|Open     Open Access   (Followers: 1)
BJS Open     Open Access   (Followers: 1)
Black Sea Journal of Health Science     Open Access  
BLDE University Journal of Health Sciences     Open Access  
Blickpunkt Medizin     Hybrid Journal  
BMC Biomedical Engineering     Open Access  
BMC Medical Ethics     Open Access   (Followers: 21)
BMC Medical Research Methodology     Open Access   (Followers: 9)
BMC Medicine     Open Access   (Followers: 13)
BMC Obesity     Open Access   (Followers: 8)
BMC Proceedings     Full-text available via subscription   (Followers: 1)
BMC Research Notes     Open Access   (Followers: 4)
BMC Sports Science, Medicine and Rehabilitation     Open Access   (Followers: 34)
BMH Medical Journal     Open Access   (Followers: 2)
BMI Journal : Bariátrica & Metabólica Iberoamericana     Open Access  
BMJ     Hybrid Journal   (Followers: 1750)
BMJ Case Reports     Hybrid Journal   (Followers: 26)
BMJ Evidence-Based Medicine     Hybrid Journal   (Followers: 3)
BMJ Global Health     Open Access   (Followers: 3)
BMJ Innovations     Hybrid Journal   (Followers: 6)
BMJ Leader     Hybrid Journal  
BMJ Open     Open Access   (Followers: 42)
BMJ Open Quality     Open Access   (Followers: 19)
BMJ Open Science     Open Access   (Followers: 1)
BMJ Sexual & Reproductive Health     Hybrid Journal   (Followers: 2)
BMJ Surgery, Interventions, & Health Technologies     Open Access  
Bodine Journal     Open Access  
Boletín del Consejo Académico de Ética en Medicina     Open Access  
Boletín del ECEMC     Open Access  
Boletin Médico de Postgrado     Open Access  
Boletín Médico del Hospital Infantil de México     Open Access  
Bone     Hybrid Journal   (Followers: 18)
Bone and Tissue Regeneration Insights     Open Access   (Followers: 2)
Bone Marrow Research     Open Access   (Followers: 2)
Bone Reports     Open Access  
Bosnian Journal of Basic Medical Sciences     Open Access  
Bozok Tıp Dergisi / Bozok Medical Journal     Open Access  
Brachytherapy     Full-text available via subscription   (Followers: 6)
Brain and Development     Full-text available via subscription   (Followers: 5)
Brain Connectivity     Hybrid Journal   (Followers: 5)
Brain Impairment     Full-text available via subscription   (Followers: 2)
Brazilian Journal of Medical and Biological Research     Open Access  
Brazilian Journal of Medicine and Human Health     Open Access  
Brazilian Journal of Pain (BrJP)     Open Access  
Brazilian Journal of Physical Therapy     Open Access   (Followers: 2)
Breastfeeding Review     Full-text available via subscription   (Followers: 18)
British Journal of Biomedical Science     Full-text available via subscription   (Followers: 7)
British Journal of General Practice     Full-text available via subscription   (Followers: 38)
British Journal of Hospital Medicine     Full-text available via subscription   (Followers: 16)
British Medical Bulletin     Hybrid Journal   (Followers: 6)
Buddhachinaraj Medical Journal     Open Access  
Bulletin Amades     Open Access  
Bulletin de la Société de pathologie exotique     Hybrid Journal   (Followers: 1)
Bulletin of Legal Medicine     Open Access  
Bulletin of Medical Sciences     Open Access  
Bulletin of the History of Medicine     Full-text available via subscription   (Followers: 18)
Bulletin of the Menninger Clinic     Full-text available via subscription  
Bulletin of The Royal College of Surgeons of England     Free  
Bulletin of the Scientific Centre for Expert Evaluation of Medicinal Products     Open Access  
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz     Hybrid Journal   (Followers: 6)
Burapha Journal of Medicine     Open Access  
Burns     Hybrid Journal   (Followers: 10)
Cadernos de Naturologia e Terapias Complementares     Open Access   (Followers: 1)
Calcified Tissue International     Hybrid Journal   (Followers: 2)
Canadian Bulletin of Medical History     Hybrid Journal  
Canadian Family Physician     Partially Free   (Followers: 13)
Canadian Journal of Pain     Open Access   (Followers: 2)
Canadian Journal of Rural Medicine     Full-text available via subscription   (Followers: 1)
Canadian Medical Association Journal     Open Access   (Followers: 17)
Canadian Medical Education Journal     Open Access   (Followers: 10)
Canadian Prosthetics & Orthotics Journal     Open Access  
Cannabis and Cannabinoid Research     Hybrid Journal   (Followers: 1)
Cardiac Electrophysiology Clinics     Full-text available via subscription   (Followers: 1)
Care Management Journals     Hybrid Journal   (Followers: 5)
Case Reports     Open Access  
Case Reports in Acute Medicine     Open Access  
Case Reports in Clinical Medicine     Open Access   (Followers: 1)
Case Reports in Clinical Nutrition     Open Access   (Followers: 1)
Case Reports in Medicine     Open Access   (Followers: 2)
Case Reports in Transplantation     Open Access  
Case Reports in Vascular Medicine     Open Access  
Case Reports in Women's Health     Open Access   (Followers: 4)
Case Study and Case Report     Open Access   (Followers: 5)
CBU International Conference Proceedings     Open Access   (Followers: 3)
Cell & Bioscience     Open Access   (Followers: 6)
Cell Adhesion & Migration     Open Access   (Followers: 9)
Cell and Molecular Response to Stress     Full-text available via subscription   (Followers: 2)
Cell and Tissue Transplantation and Therapy     Open Access   (Followers: 2)
Cell Cycle     Full-text available via subscription   (Followers: 6)
Cell Death and Differentiation     Hybrid Journal   (Followers: 7)
Cell Death Discovery     Open Access   (Followers: 1)
Cell Health and Cytoskeleton     Open Access   (Followers: 1)
Cell Medicine     Open Access   (Followers: 6)
Cell Research     Hybrid Journal   (Followers: 8)
Cell Transplantation     Open Access   (Followers: 4)
CEN Case Reports     Hybrid Journal  
Central African Journal of Medicine     Full-text available via subscription  
Ceylon Journal of Medical Science     Open Access  
Ceylon Medical Journal     Open Access  
Chattagram Maa-O-Shishu Hospital Medical College Journal     Open Access  
Chiang Mai Medical Journal     Open Access  
ChiangRai Medical Journal     Open Access  
Chimerism     Full-text available via subscription  
Chinese Journal of Integrative Medicine     Hybrid Journal   (Followers: 3)
Chinese Journal of Natural Medicines     Full-text available via subscription   (Followers: 1)
Chinese Medical Journal     Open Access   (Followers: 10)
Chinese Medical Record English Edition     Hybrid Journal  
Chinese Medical Sciences Journal     Full-text available via subscription   (Followers: 2)
Chinese Medicine     Open Access   (Followers: 2)
Chinese Medicine     Open Access   (Followers: 4)
Chisholm Health Ethics Bulletin     Full-text available via subscription   (Followers: 1)
CHRISMED Journal of Health and Research     Open Access   (Followers: 2)
Christian Journal for Global Health     Open Access  
Chronic Diseases and Translational Medicine     Open Access  
Chronic Illness     Hybrid Journal   (Followers: 6)
Chronic Wound Care Management and Research     Open Access   (Followers: 4)
Chronobiology International     Hybrid Journal   (Followers: 3)
ChronoPhysiology and Therapy     Open Access  
Chulalongkorn Medical Bulletin     Open Access  
Chulalongkorn Medical Journal     Open Access  
Ciencia e Innovación en Salud     Open Access  
Ciencia e Investigación Medico Estudiantil Latinoamericana     Open Access  

  First | 1 2 3 4 5 6 7 8 | Last

Similar Journals
Journal Cover
Biomedical Microdevices
Journal Prestige (SJR): 0.538
Citation Impact (citeScore): 2
Number of Followers: 8  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 1572-8781 - ISSN (Online) 1387-2176
Published by Springer-Verlag Homepage  [2570 journals]
  • Research Progress of nucleic acid delivery vectors for gene therapy
    • Abstract: Abstract Gene therapy has broad prospects as an effective treatment for some cancers and hereditary diseases. However, DNA and siRNA are easily degraded in vivo because of their biological activities as macromolecules, and they need the effective transmembrane delivery carrier Selecting the appropriate carrier for delivery will allow nucleic acid molecules to reach their site of action and enhance delivery efficiency. Currently used nucleic acid delivery vectors can be divided into two major categories: viral and non-viral vectors. Viral carrier transport efficiency is high, but there are safety issues. Non-viral vectors have attracted attention because of their advantages such as low immunogenicity, easy production, and non-tumorigenicity. The construction of safe, effective, and controllable vectors is the focus of current gene therapy research. This review presents the current types of nucleic acid delivery vehicles, which focuses on comparing their respective advantages and limitations, and proposes a novel delivery system, RNTs, a novel nanomolecular material, introducing the characteristics and nucleic acid delivery process of RNTs and their latest applications.
      PubDate: 2020-01-27
       
  • Analysis of the capacitance of minimally insulated parallel wires
           implanted in biological tissue
    • Abstract: Abstract State of the art bioelectronic implants are using thin cables for therapeutic electrical stimulation. If cable insulation is thin, biological tissue surrounding cables can be unintentionally stimulated. The capacitance of the cable must be much less than the stimulating electrodes to ensure stimulating currents are delivered to the electrode-tissue interface. This work derives and experimentally validates a model to determine the capacitance of parallel cables implanted in biological tissue. Biological tissue has a high relative permittivity, so the capacitance of cabling implanted in the human body depends on cable insulation thickness. Simulations and measurements demonstrate that insulation thickness influences the capacitance of implanted parallel cables across almost two orders of magnitude: from 20 pF/m to 700 pF/m. The results are verified using four different methods: solving the Laplacian numerically from first principles, using a commercially available electrostatic solver, and measuring twelve different parallel pairs of wires using two different potentiostats. Cable capacitance simulations and measurements are performed in air, a porcine blood pool and porcine muscle tissue. The results do not differ by more than 30% for a given cable across simulation and measurement methodologies. The modelling in this work can be used to design cabling for minimally-invasive biomedical implants.
      PubDate: 2020-01-21
       
  • Enhancing droplet transition capabilities using sloped microfluidic
           channel geometry for stable droplet operation
    • Abstract: Abstract Droplet-based microfluidics technology allows for the generation and control of droplets that function as independent chemical and biological reactors, enabling broad ranges of high-throughput assays. As more complex multi-step assays are being realized in droplet format, maintaining droplet stability throughout the assay becomes a critical requirement. Unfortunately, as droplets go through multiple manipulation steps, droplet breakage is commonly seen, especially where droplets have to go through sharp transitions in direction and shape. Standard microfabrication techniques typically result in inherent sharp geometry in Z-direction due to their two-dimensional fabrication nature. Recent advancement in micro- and nano- fabrication technology using two-photon polymerization (2PP) is enabling complex 3D microstructures with sub-micrometer resolution to be readily fabricated. Here, utilizing this microfabrication technique, we present a simple solution to the droplet stability challenge by utilizing sloped-geometry microfluidic channels to enable microdroplets to smoothly transition between microfluidic channels having two different heights without breakage. The technique and innovation demonstrated here have the potential to replace conventional droplet microfluidic device fabrication approaches and enable droplet microfluidic platforms to achieve significantly higher level of efficiency, accuracy, and stability never realized before.
      PubDate: 2020-01-21
       
  • On-chip simultaneous rotation of large-scale cells by acoustically
           oscillating bubble array
    • Abstract: Abstract Bubbles locating in microfluidic chamber can produce acoustic streaming vortices by applying travelling surface acoustic wave oscillation in an ultrasonic range, which can be used to drive bio-samples to move within the flow field. In this paper, a strategy of bubble array configured in a large number of regularly arranged horseshoe structures is proposed to capture and rotate cells simultaneously. By modifying the geometric parameters of the horseshoe structure and microfluidic setting, high bubble homogeneity and cell trapping percentage was achieved. The simulation and experimental results of the bubble-induced streaming vortices were confirmed to be consistent. Through experiments, we achieved both in-plane and out-of-plane rotation of arrayed HeLa cells trapped by the bubbles. Out-of-plane rotation was used to reconstruct the 3D (three-dimensional) cell morphology, which was demonstrated to be useful in calculating cell geometry related parameters. We believe that this bubble array based cell rotation method is expected to be a promising tool for the investigation of bioengineering, biophysics, medicine, and cell biology.
      PubDate: 2020-01-18
       
  • Fabrication of separable microneedles with phase change coating for
           NIR-triggered transdermal delivery of metformin on diabetic rats
    • Abstract: Abstract To enhance the compliance of drug delivery for patients, the novel near-infrared (NIR) light-triggered and separable microneedles (MNs) have been developed in this work. Firstly, prussian blue nanoparticles (PB NPs) as the photo-thermal conversion factor and metformin as the hypoglycemic drug were embedded into the separable arrowheads, which consisted by poly (vinyl alcohol) and sucrose (PVA/Suc). The arrowheads of MNs were located on soluble solids supporting substrates that produced by poly(vinyl pyrrolidone) (PVP). Lauric acid (LA) as the phase transition coating covered on the surface of the MNs due to its lower phase transition temperature (~44 °C). Then, the separable arrowheads could be left into the skin because of the absorbing the interstitial fluid (IF) by the solid supporting substrates. With the irradiation of NIR light, LA could be melted due to the role of PB NPs in photo-thermal conversion, thus releasing the metformin from arrowheads. Compared with the traditional subcutaneous injections, the hypoglycemic effect was evaluated by the drug-release behaviors induced by NIR in vivo. The results showed that metformin could be allowed to on-demand release under the NIR irradiation. And the as-obtained MNs exhibited a good hypoglycemic effect, hypotoxicity and low inflammation reaction compared with those of traditional subcutaneous injections. The results indicate that the fabricated MNs have the potential treatment for diabetes due to their safety, convenience and painlessness.
      PubDate: 2020-01-07
       
  • Development of a new and simple method for the detection of
           histidine-tagged proteins based on thionine-chitosan/gold
           nanoparticles/horseradish peroxidase
    • Abstract: Abstract In the current study, an electrochemical biosensing signal amplification system was utilized with thionine-chitosan-gold nanoparticles (Chit-GNPs) that absorbed horseradish peroxidase (HRP) and anti-His tagged protein monoclonal antibody derived from Balb/c mice. In addition, transmission electron microscopy (TEM) was used to characterize the nanogold solution and atomic force microscopy (AFM) was used to characterize the sensor assembly. To evaluate the quality of the immunosensor, the amperometric I-t curve method was applied to determine His-IL23 in PBS. The results indicated that the response current exhibited an optimal linear correlation with the His-IL23 concentration that ranged from 0.01 to 103 ng/ml. The lowest detection limit was noted at 3.3 pg/ml (S/N = 3). The linear equation was deduced as follows: △I = 0.02lgC + 0.037 (R2 = 0.9628). Moreover, it was validated with high sensitivity, reproducibility and rapid response. Apparently, the immunosensor may be a very useful tool for the detection and quantification of His-tagged proteins. In addition, the signal amplification system can be used for the preparation of other immunosensors and to assist in bioassays.
      PubDate: 2020-01-02
       
  • Bioprinting a 3D vascular construct for engineering a vessel-on-a-chip
    • Abstract: Abstract The organ-on-a-chip model mimics the structural and functional features of human tissues or organs and has great importance in translational research. For vessel-on-a-chip model, conventional fabrication techniques are unable to efficiently imitate the intimal-medial unit of the vessel wall. Bioprinting technology, which can precisely control the organization of cells, biomolecules, and the extracellular matrix, has the potential to fabricate three-dimensional (3D) tissue constructs with spatial heterogeneity. In this study, we applied the gelatin-methacryloyl-based bioprinting technology to print 3D construct containing endothelial cells (ECs) and smooth muscle cells (SMCs) on a microfluidic chip. Compared with traditional culture system, EC-SMC coculturing chip model upregulated αSMA and SM22 protein expression of the SMC to a greater degree and maintains the contractile phenotype of the SMC, which mimics the natural vascular microenvironment. This strategy enabled us to establish an in vitro vascular model for studies of the physiologic and pathologic process in vascular wall.
      PubDate: 2019-12-26
       
  • Microfluidic vascular-bed devices for vascularized 3D tissue engineering:
           tissue engineering on a chip
    • Abstract: Abstract In this report, we describe a microfluidic vascular-bed (micro-VB) device providing a platform for 3D tissue engineering with vascular network formation. The micro-VB device allows functional connections between endothelial capillaries of heterogeneous sections (5–100 μm in diameter) and artificial plastic tubes or reservoirs (1–10 mm in diameter). Moreover, the micro-VB device can be installed in a standard 100 mm-diameter Petri dish. Endothelial networks in 3D engineered tissues were obtained by cellular self-assembly on the device, after co-culturing of human umbilical vein endothelial cells (HUVECs) and normal human dermal fibroblasts (NHDFs) in fibrin gel. Endothelial capillary connection between vascularized tissues and microfluidic channels, mimicking arteries and veins, was confirmed by perfusion of fluorescent microspheres. The micro-VB devices were compatible with the use of commercially available culture dishes and did not require the involvement of additional equipment. Thus, these micro-VB devices are expected to substantially improve the routine application of 3D tissue engineering to regenerative medicine.
      PubDate: 2019-12-20
       
  • Paper based point of care immunosensor for the impedimetric detection of
           cardiac troponin I biomarker
    • Abstract: Abstract Advancements in health care monitoring demand a rapid, accurate and reliable early diagnosis of “Heart Attack” (acute myocardial infarction) with an objective to develop a cost-effective, rapid and label-free point of care diagnostic test kit for the detection of cardiac troponin I (cTnI) on paper-based multi-frequency impedimetric transducers. Paper based sensing platforms were developed by integrating carboxyl group functionalized multi-walled carbon nanotubes (MWCNT) with antibodies of cardiac troponin I (anti-cTnI) biomarker and was characterized using Electrochemical Impedance Spectroscopy (EIS). Various concentrations of cTnI with anti cTnI were studied as a function of impedance change. The suitability of the proposed immunosensor is demonstrated by spiking cTnI in blood serum samples. The limit of detection (LoD) and sensitivity of the proposed sensor was determined to be 0.05 ng/mL and 1.85 mΩ/ng/mL respectively, with a response time of ~1 min. The shelf life of the fabricated sensor was nearly 30 days. The rapid response, very low detection limit, and cost effectiveness offer a portable platform to detect cTnI in blood serum samples. The proposed immunosensor, therefore, offers an affordable healthcare diagnostic platform in resource limited areas.
      PubDate: 2019-12-16
       
  • Coated microneedles for transdermal delivery of a potent pharmaceutical
           peptide
    • Abstract: Minimally invasive delivery of peptide and protein molecules represents a significant opportunity for product differentiation and value creation versus standard injectable routes of administration. One such technology utilizes microneedle (MN) patches and it has made considerable clinical advances in systemic delivery of potent macromolecules and vaccines. A sub-class of this technology has focused on preparation of solid dense MN arrays followed by precision formulation coating on the tips of the MN. The objective of this study was to develop a drug product using the MN technology that has similar bioperformance when compared to subcutaneous route of delivery and can provide improved stability under storage. Therapeutic peptide (Peptide A, Merck & Co., Inc., Kenilworth, NJ, USA) is being developed as a subcutaneous injection for chronic dosing with a submilligram estimated therapeutic dose. Peptide A has chemical and physical stability challenges in solution and this led to exploration of a viable drug product which could provide therapeutic dosages while overcoming the stability issues seen with the compound. This work focused on developing a coated solid microstructure transdermal system (sMTS) for Peptide A followed by detailed in vitro and preclinical evaluation for two different coating formulations. Based on initial assessment, ~250 μg of Peptide A could be coated with precision on a 1.27cm2 patch which contained 316 MN’s. The delivery from these systems was achieved with absolute bioavailability being similar to the subcutaneous delivery (88% and 74% for coated sMTS 1 & 2 and 75% for subcutaneous delivery). Stability of Peptide A was also found to be significantly improved when coated on the sMTS system with minimal degradation recorded at room temperature storage as compared to the subcutaneous liquid formulation. Additionally, skin irritation (on pig skin) was also measured in this study and it was found to be minimal and self-resolving. This evaluation provided a viable option for developing a drug product with improved stability and successful delivery of the investigated molecule. Graphical abstract Schematic showing uncoated sMTS, resulting product with coated peptide, successful skin penetration with high delivery efficiency and bioavailability.
      PubDate: 2019-12-16
       
  • Bio-inspired microneedle design for efficient drug/vaccine coating
    • Abstract: Abstract Biomimetics is the interdisciplinary scientific field focused on the study and imitation of biological systems, with the aim of solving complex technological problems. In this paper, we present a new bio-inspired design for microneedles (MNs) and MN arrays, intended for rapidly coating the MNs with drug/vaccine. The biomimetic approach consists in ornamenting the lateral sides of pyramidal MNs with structures inspired by the external scent efferent systems of some European true bugs, which facilitate a directional liquid transport. To realize these MNs, two-photon polymerization (TPP) technique was used. Liquid coating capabilities of structured and non-structured MNs were compared. Moreover, both in-vivo and ex-vivo skin tests were performed to prove that MNs pierce the skin. We show that the arrays of MNs can be accurately replicated using a micro-moulding technique. We believe this design will be beneficial for the process of drug/vaccine loading onto the needles’ surfaces, by making it more efficient and by reducing the drug/vaccine wastage during MN coating process.
      PubDate: 2019-12-16
       
  • Design and fabrication of portable continuous flow PCR microfluidic chip
           for DNA replication
    • Abstract: Abstract The reasons for restricting continuous flow polymerase chain reaction (CF-PCR) microfluidic chip from lab to application are that it is not portable and requires costly external precision pumps for sample injection. Herein, we employed water as the substitute for PCR solution, and investigated the effect of the cross-section, width-to-depth ratio, and the length ratio for three temperature zones of the micro channel on the thermal and flow distribution of fluid in micro tube by finite element analysis. Results show that the central velocity is uniform and stable velocity occupies the most if the cross-section is rectangular. The deviation between predefined temperature and theoretical temperature is slight and the fluid flux is the most if width-to-depth ratio is 1:1. It is suitable for the short DNA replication if the high temperature zone Wh is larger than the low temperature zone Wl, and vice versa. Then a portable CF-PCR microfluidic chip was fabricated and an automatic sample injection system was developed. As an application, we have successfully amplified the DNA of Treponema denticola in the chip within 8 min. Such a study may offer new insight into the design of CF-PCR microfluidic chip and promote it from lab-scale research to full-scale application.
      PubDate: 2019-12-10
       
  • Development of rolled scaffold for high-density adherent cell culture
    • Abstract: Abstract Bioreactors for large-scale culture of mammalian cells are playing vital roles in biotechnology and bioengineering. Various bioreactors have been developed, but their capacity and efficiency are often limited by insufficient mass transfer rate and high shear stress. A rolled scaffold (RS) is a fully defined scaffold for high-density adherent culture of mammalian cells. The RS is a polymer film with spacers, that is rolled into a cylinder with a pre-determined gap between each turn. Cells are cultured on its inner surfaces, while media flows through the gap. The RS exhibits high surface-area-to-volume ratio over 100 cm2/mL and can transport nutrients and gases with significantly reduced shear stress via convection in a unidirectional laminar flow, rather than diffusion and random turbulent flow as in stirred-tank bioreactors. In this paper, we expanded Chinese Hamster Ovary cells with RS bioreactors and demonstrated cell culture density over 60 million cells/mL with a growth rate higher than conventional suspension culture. Besides, murine embryonic stem cells were successfully expanded without losing their pluripotency. The RS will provide an affordable, scalable, and reliable platform for large-scale culture of recombinant cells in biopharmaceutical industries and shear-sensitive stem cells for tissue engineering.
      PubDate: 2019-12-07
       
  • Estimation of pO 2 histogram from a composite EPR Spectrum of multiple
           random implants
    • Abstract: Abstract Electron paramagnetic resonance (EPR) spectroscopy using oxygen-sensing implants can provide reliable and repeated measurements of the partial pressure of oxygen (pO2) over a period of months or longer; however, it does not provide accurate information about the distribution of tissue oxygenation. While EPR imaging has the capability to provide spatially resolved oxygen data, it is time-consuming and not optimized for discrete number of implants. Previous reports suggest multi-site algorithms, which would require either the implants to be aligned in a certain way so as to deconvolve them using a linear magnetic field gradient or sparse imaging of the implants from a small number of 3D projections. In this paper, we present a simpler and much faster method to estimate the pO2 histogram from a composite, single-scan EPR spectrum measured without applying field gradients to separate the EPR signals from multiple randomly placed oxygen-sensing implants. The method is optimized for a discrete number of implants, validated using simulations, experimental phantoms and in animal models. The results established the composite spectral fitting algorithm as a reliable and robust tool for multi-site oximetry.
      PubDate: 2019-12-03
       
  • An overview on the exponential growth of non-invasive diagnosis of
           diabetes mellitus from exhaled breath by nanostructured metal oxide
           Chemi-resistive gas sensors and μ-preconcentrator
    • Abstract: The characterization of acetone in exhaled breath reflects the internal metabolism of glucose in bloodstream and airways. This phenomenon provides a great potential for non-invasive diagnosis of diabetes mellitus and has inspired medical sodalities as an alternative diagnostic tool. This review discusses about the origination of acetone in breath, its correlation with blood glucose level along with the ways to collect breath sample. Furthermore, we also discuss the detection of acetone by chemical sensors with emphasis on the use of pre-concentrators on a single lab-on-chip for the diagnosis of diabetes mellitus. Finally, this review outlines the future directions for the detection of acetone from exhaled breath. The first part of the review introduces the biochemistry and prevalence of diabetes in India along with the existing techniques to estimate the concentration of acetone. The second part focuses on the semiconducting metal oxide and polymer gas sensors which discusses about tailoring the dynamic sensitivity range and selectivity towards acetone in breath. The third part elaborates on the ways to pre-concentrate the target biomarkers along with future perspectives for non-invasive diabetes diagnosis. Finally we also provide the perspectives on future challenges to make it to clinical practice. Graphical abstract .
      PubDate: 2019-12-03
       
  • One-step microchip for DNA fluorescent labeling
    • Abstract: Abstract In this study, we propose a microchip that is sequentially capable of fluorescently staining and washing DNAs. The main advantage of this microchip is that it allows for one-step preparation of small amounts of solution without degrading microscopic bio-objects such as the DNAs, cells, and biomolecules to be stained. The microchip consists of two inlets, the main channel, staining zone, washing zone, and one outlet, and was processed using a femtosecond laser system. High molecular transport of rhodamine B to deionized water was observed in the performance test of the microchip. Results revealed that the one-step procedure of on-chip DNA staining and washing was excellent compared to the conventional staining method. The one-step preparation of stained and washed DNAs through the microchip will be useful for preparing small volumes of experimental samples.
      PubDate: 2019-11-28
       
  • Soft dry electroophthalmogram electrodes for human machine interaction
    • Abstract: Abstract Current soft surface electrodes have attracted more and more attentions owing to their potential applications in biological signal monitoring, human-machine interaction (HMI) and Internet of Things (IoT). The paper presents that soft dry electrode based on polydimethylsiloxane-carbon black (PDMS-CB) conductive polymer is designed and fabricated to continuous, long-term, stable electroophthalmogram (EOG) signal recordings for HMI applications. The features corresponding to the different eye motions are extracted from the EOG data via the soft dry electrodes. Linear discriminant analysis (LDA) recognition algorithms are proposed to recognize eye motion behaviors for controlling the motion of the mobile robots. Experiment results have been demonstrated that LDA recognition algorithm achieves a relatively high recognition accuracy of 90.63% for recognizing four eye movements (‘Up’, ‘Down’, ‘Right’, and ‘Left’). The control commands are generated with different eye motions and transmitted to the mobile robot through WiFi communication unit, which the mobile robot is successfully controlled. The soft dry electrodes have the potential in a comfortable, simple, wearable and wireless control of rehabilitation devices.
      PubDate: 2019-11-27
       
  • Fabrication and characterization of hyaluronic acid microneedles to
           enhance delivery of magnesium ascorbyl phosphate into skin
    • Abstract: Abstract This study investigated the in vitro transdermal delivery of magnesium ascorbyl phosphate (MAP) through porcine ear skin treated with hyaluronic acid (HA) microneedles (MNs). In this study, the micro-molding method was used to fabricate HA MNs. HA solution (10% w/v) containing 3% of MAP was placed onto a poly(dimethyl siloxane) mold to fill the microchannels under vacuum followed by drying in a desiccator. Scanning electron microscopy was performed to record the dimensions of the MNs. Skin microporation was demonstrated by dye binding. Histological skin sections revealed the shape of microchannels under hematoxylin-eosin staining. The actual depth of the microchannels and drug distribution pathways were studied by confocal microscopy. In vitro permeation on Franz diffusion cells were performed to determine the rate and extent of drug delivery into and across the skin. SEM captured individual MNs from the array, and the length of each MN was found to be ~400 μm. The 10 × 10 MN array prepared, resulted in the formation of 95 to 100 microchannels after 2 mins of treatment. In addition, the histological evaluations showed the formation of microchannels in the skin, complementary in shape to the MNs. The depths of the formed microchannels amounted to ~125 μm as determined by confocal microscopy. The application of the current MN technology enhanced the delivery of MAP into skin (96.8 ± 3.9 μg/cm2) compared to the passive delivery strategy of MAP (44.9 ± 16.3 μg/cm2). HA MNs markedly enhanced the in vitro transdermal delivery of MAP into and across skin.
      PubDate: 2019-11-27
       
  • A theoretical study on real time monitoring of single cell mitosis with
           micro electrical impedance tomography
    • Abstract: Abstract Real time monitoring of cell division, mitosis, at the single cell level, has value for many biomedical applications; such as developing optimal cancer treatments that target the cell division process. The goal of this theoretical study is to explore the feasibility of using Micro Electrical Impedance Tomography (MEIT) for real time monitoring of mitosis in a single cell, through imaging. MEIT employs a micro (single cell) scale electrode cage with electrodes placed around the cell. The electrodes deliver subsensory current and the consequential voltages on the electrodes are measured. An inverse image reconstruction algorithm uses the electric data from the electrodes to generate a map of electrical conductivity distribution in the chamber, which is the image. EIT is a well-known medical imaging technology that is simple to use but lacks good resolution. Therefore, it is not a-priori obvious that EIT has sufficient resolution to monitor single cell mitosis. To accomplish the goal of this study we have developed a mathematical model of MEIT of single cell mitosis, in which an in silico experiment provided the data for the MEIT image reconstruction. This theoretical study shows that MEIT can detect the outlines of the dividing cell during the various stages of mitosis (metaphase, anaphase and telophase) and, therefore, has potential as a technology for real time monitoring of single cell mitosis.
      PubDate: 2019-11-25
       
  • Characterizing the invasion of different breast cancer cell lines with
           distinct E-cadherin status in 3D using a microfluidic system
    • Abstract: Abstract E-cadherin is a cell-cell adhesion protein that plays a prominent role in cancer invasion. Inactivation of E-cadherin in breast cancer can arise from gene promoter hypermethylation or genetic mutation. Depending on their E-cadherin status, breast cancer cells adopt different morphologies with distinct invasion modes. The tumor microenvironment (TME) can also affect the cell morphology and invasion mode. In this paper, we used a previously developed microfluidic system to quantify the three-dimensional invasion of breast cancer cells with different E-cadherin status, namely MCF-7, CAMA-1 and MDA-MB-231 with wild type, mutated and promoter hypermethylated E-cadherin, respectively. The cells migrated into a stable and reproducible microfibrous polycaprolactone mesh in the chip under a programmed stable chemotactic gradient. We observed that the MDA-MB-231 cells invaded the most, as single cells. MCF-7 cells collectively invaded into the matrix more than CAMA-1 cells, maintaining their E-cadherin expression. The CAMA-1 cells exhibited multicellular multifocal infiltration into the matrix. These results are consistent with what is seen in vivo in the cancer biology literature. In addition, comparison between complete serum and serum gradient conditions showed that the MDA-MB-231 cells invaded more under the serum gradient after one day, however this behavior was inverted after 3 days. The results showcase that the microfluidic system can be used to quantitatively assess the invasion behavior of cancer cells with different E-cadherin expression, for a longer period than conventional invasion models. In the future, it can be used to quantitatively investigate effects of matrix structure and cell treatments on cancer invasion.
      PubDate: 2019-11-23
       
 
JournalTOCs
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Email: journaltocs@hw.ac.uk
Tel: +00 44 (0)131 4513762
 


Your IP address: 3.229.142.175
 
Home (Search)
API
About JournalTOCs
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-