103 research outputs found
Keratin/Polyvinyl Alcohol Blend Films Cross-Linked by Dialdehyde Starch and Their Potential Application for Drug Release
Feather keratin (FK) extracted from feathers represents a valuable source of biodegradable and biocompatible polymer. The aim of this study was the development and characterization of blended films based on FK and polyvinyl alcohol (PVA) cross-linked by dialdehyde starch (DAS) for a potential drug release application. The compatibility of FK/PVA was improved when cross-linked by DAS: the relative crystallinity of the PVA/FK film slightly decreased, and the enthalpy value for the melting peak decreased by about 50% for the cross-linked films. The total soluble mass of all blend films in water was below 35% at 37 °C, indicating a good stability of the films in water. The results of the Rhodamine B dye (as a model drug) release tests showed that the release rates decreased with increasing DAS content. DAS-induced cross-linking improves several important properties of the FK/PVA films, such as the compactness, the compatibility, and the stability in water. These improvements offer the potential to expand the application of FK films in the biomaterial field
Synthesis of the polymerizable room temperature ionic liquid AMPS – TEA and superabsorbency for organic liquids of its copolymeric gels with acrylamide
A polymerizable room temperature ionic liquid (RTIL), 2-acrylamido-2-methyl-1-propane sulfonic acid (AMPS) – triethylamine (TEA), was synthesized by neutralization of AMPS with TEA in acetone followed by evaporation of the solvent under a reduced pressure at room temperature. The RTIL was characterized with fourier transform infrared spectroscopy, differential scanning calorimetry (DSC), and 1H NMR. Co-polymeric gels of the RTIL with acrylamide (AAm) were prepared by aqueous solution polymerization using N,N′-methylenebisacrylamide as a crosslinker, and ammonium persulfate as an initiator. Superabsorbency of the gels in aqueous and a series of organic liquids was investigated gravimetrically. DSC data showed that the glass transition temperature of AMPS – TEA was 59.4 °C. Poly (AMPS – TEA-co-AAm) gels exhibited superabsorbency in both water and a series of organic solvents. The mechanism for swelling in aqueous and organic media of the gels was critically discussed
How a Diverse Research Ecosystem Has Generated New Rehabilitation Technologies: Review of NIDILRR’s Rehabilitation Engineering Research Centers
Over 50 million United States citizens (1 in 6 people in the US) have a developmental, acquired, or degenerative disability. The average US citizen can expect to live 20% of his or her life with a disability. Rehabilitation technologies play a major role in improving the quality of life for people with a disability, yet widespread and highly challenging needs remain. Within the US, a major effort aimed at the creation and evaluation of rehabilitation technology has been the Rehabilitation Engineering Research Centers (RERCs) sponsored by the National Institute on Disability, Independent Living, and Rehabilitation Research. As envisioned at their conception by a panel of the National Academy of Science in 1970, these centers were intended to take a “total approach to rehabilitation”, combining medicine, engineering, and related science, to improve the quality of life of individuals with a disability. Here, we review the scope, achievements, and ongoing projects of an unbiased sample of 19 currently active or recently terminated RERCs. Specifically, for each center, we briefly explain the needs it targets, summarize key historical advances, identify emerging innovations, and consider future directions. Our assessment from this review is that the RERC program indeed involves a multidisciplinary approach, with 36 professional fields involved, although 70% of research and development staff are in engineering fields, 23% in clinical fields, and only 7% in basic science fields; significantly, 11% of the professional staff have a disability related to their research. We observe that the RERC program has substantially diversified the scope of its work since the 1970’s, addressing more types of disabilities using more technologies, and, in particular, often now focusing on information technologies. RERC work also now often views users as integrated into an interdependent society through technologies that both people with and without disabilities co-use (such as the internet, wireless communication, and architecture). In addition, RERC research has evolved to view users as able at improving outcomes through learning, exercise, and plasticity (rather than being static), which can be optimally timed. We provide examples of rehabilitation technology innovation produced by the RERCs that illustrate this increasingly diversifying scope and evolving perspective. We conclude by discussing growth opportunities and possible future directions of the RERC program
Leptin induces TNFα-dependent inflammation in acquired generalized lipodystrophy and combined Crohn’s disease
Gene therapy for monogenic liver diseases: clinical successes, current challenges and future prospects
Over the last decade, pioneering liver-directed gene therapy trials for haemophilia B have achieved sustained clinical improvement after a single systemic injection of adeno-associated virus (AAV) derived vectors encoding the human factor IX cDNA. These trials demonstrate the potential of AAV technology to provide long-lasting clinical benefit in the treatment of monogenic liver disorders. Indeed, with more than ten ongoing or planned clinical trials for haemophilia A and B and dozens of trials planned for other inherited genetic/metabolic liver diseases, clinical translation is expanding rapidly. Gene therapy is likely to become an option for routine care of a subset of severe inherited genetic/metabolic liver diseases in the relatively near term. In this review, we aim to summarise the milestones in the development of gene therapy, present the different vector tools and their clinical applications for liver-directed gene therapy. AAV-derived vectors are emerging as the leading candidates for clinical translation of gene delivery to the liver. Therefore, we focus on clinical applications of AAV vectors in providing the most recent update on clinical outcomes of completed and ongoing gene therapy trials and comment on the current challenges that the field is facing for large-scale clinical translation. There is clearly an urgent need for more efficient therapies in many severe monogenic liver disorders, which will require careful risk-benefit analysis for each indication, especially in paediatrics
IBD risk loci are enriched in multigenic regulatory modules encompassing putative causative genes.
GWAS have identified >200 risk loci for Inflammatory Bowel Disease (IBD). The majority of disease associations are known to be driven by regulatory variants. To identify the putative causative genes that are perturbed by these variants, we generate a large transcriptome data set (nine disease-relevant cell types) and identify 23,650 cis-eQTL. We show that these are determined by ∼9720 regulatory modules, of which ∼3000 operate in multiple tissues and ∼970 on multiple genes. We identify regulatory modules that drive the disease association for 63 of the 200 risk loci, and show that these are enriched in multigenic modules. Based on these analyses, we resequence 45 of the corresponding 100 candidate genes in 6600 Crohn disease (CD) cases and 5500 controls, and show with burden tests that they include likely causative genes. Our analyses indicate that ≥10-fold larger sample sizes will be required to demonstrate the causality of individual genes using this approach
Effects of the Structure and Composition of Montmorillonite on the Dimerization of Unsaturated Fatty Acids
Thermal Flow Self-Assembled Anisotropic Chemically Derived Graphene Aerogels and Their Thermal Conductivity Enhancement
In this study, we investigated the directional heating of graphene oxide (GO) dispersion to generate a temperature gradient and form a simulated “ocean current” inside the dispersion so that GO sheets could be aligned in a directional manner and then reduced and self-assembled into anisotropic reduced graphene oxide (rGO) gel. After freeze-drying and varying degrees of vacuum microwave treatment, anisotropic chemically derived graphene aerogels (AGAs) were obtained. Through performance detection and the analysis of the results, it was verified that the AGAs with certain characteristics of “ocean current” were prepared in this experiment, and its axial direction has obvious directional arrangement. After being treated by vacuum microwave for a short time (1 min.), the axial thermal conductivity of the composite materials (AGA-adsorbed paraffin) was observed to be 1.074 W/mK, and the thermal conductivity enhancement efficiency was 995%; as compared with similar thermal conductivity enhancement composites that were found in previous studies, the proposed method in this paper has the advantages of simple processing, high efficiency, and energy conservation
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