Hydrogels for biomedical applications.

EpiXS: A Windows-based program for photon attenuation, dosimetry and shielding based on EPICS2017 (ENDF/B-VIII) and EPDL97 (ENDF/B-VI.8)

An injectable, biodegradable hydrogel composite of oligo(poly(ethylene glycol) fumarate) (OPF) and gelatin microparticles (MPs) has been investigated as a cell and growth factor carrier for cartilage tissue engineering applications. In this study, hydrogel composites with different swelling ratios were prepared by cross-linking OPF macromers with poly(ethylene glycol) (PEG) repeating units of varying molecular weights from 1000 approximately 35000. Rabbit marrow mesenchymal stem cells (MSCs) and MPs loaded with transforming growth factor-beta1 (TGF-beta1) were encapsulated in the hydrogel composites to examine the effect of the swelling ratio of the hydrogel composites on the chondrogenic differentiation of encapsulated rabbit marrow MSCs both in the presence and in the absence of TGF-beta1. The swelling ratio of the hydrogel composites increased as the PEG molecular weight in the OPF macromers increased. Chondrocyte-specific genes were expressed at higher levels in groups containing TGF-beta1-loaded MPs and varied with the swelling ratio of the hydrogel composites. OPF hydrogel composites with PEG repeating units of molecular weight 35000 and 10000 with TGF-beta1-loaded MPs exhibited a 159 +/- 95- and a 89 +/- 31-fold increase in type II collagen gene expression at day 28, respectively, while OPF hydrogel composites with PEG repeating units of molecular weight 3000 and 1000 with TGF-beta1-loaded MPs showed a 27 +/- 10- and a 17 +/- 7-fold increase in type II collagen gene expression, respectively, as compared to the composites with blank MPs at day 0. The results indicate that chondrogenic differentiation of encapsulated rabbit marrow MSCs within OPF hydrogel composites could be affected by their swelling ratio, thus suggesting the potential of OPF composite hydrogels as part of a novel strategy for controlling the differentiation of stem cells.

Effect of swelling ratio of injectable hydrogel composites on chondrogenic differentiation of encapsulated rabbit marrow mesenchymal stem cells in vitro

Expert biochemist N.V. Bhagavan's new work condenses his successful \"Medical Biochemistry\" texts along with numerous case studies, to act as an extensive review and reference guide for both students and experts alike. The research-driven content includes four-color illustrations throughout to develop an understanding of the events and processes that are occurring at both the molecular and macrolecular levels of physiologic regulation, clinical effects, and interactions. Using thorough introductions, end of chapter reviews, fact-filled tables, and related multiple-choice questions, Bhagavan provides the reader with the most condensed yet detailed biochemistry overview available. More than a quick survey, this comprehensive text includes USMLE sample exams from Bhagavan himself, a previous co-author. Clinical focus emphasizing relevant physiologic and pathophysiologic biochemical concepts. Interactive multiple-choice questions to prep for USMLE exams. Clinical case studies for understanding basic science, diagnosis, and treatment of human diseases. Instructional overview figures, flowcharts, and tables to enhance understanding.

Essentials of medical biochemistry: With clinical cases

Thermal stability and gamma ray shielding properties of tungsten borides/epoxy micro-composites

Micro and nano Bi2O3 filled epoxy composites: Thermal, mechanical and γ-ray attenuation properties.

Sodium alginate/bismuth (III) oxide composites for γ‐ray shielding applications

Abstract Use of X-rays and γ-rays have become inevitable in medical sectors like radiology, interventional cardiology and diagnostic imaging, radiation physics laboratories, nuclear reactors and accelerator facilities. As radiation exposures above permitted levels pose potential risk to personnel working in close proximity to these facilities, protective measures aimed at reducing the exposure for safeguarding against harmful effects of ionizing radiations are essential. Traditionally, lead and lead based materials have been used as efficient radiation shielding materials owing to the high atomic number and high density of lead. Presently, use of lead is discouraged due to its heavy weight, toxicity and long-term effects on the environment. Consequently, the last two decades have seen research on light weight and cost-effective polymer composites with appropriate additives, having good workability, high specific strength, thermo-chemical stability and radiation shielding efficacy, gaining momentum. This article gives an overview of the state-of-the-art polymer composites reinforced with different fillers studied for their use as effective radiation shields. Here, we summarize the recent advancement and current trends in polymer composites-based radiation shields highlighting the different approaches adopted, choice of polymer/fillers, shielding effectiveness in terms of either linear and/or mass attenuation coefficients, for those who venture into radiation research and development.

Srilakshmi Prabhu

Papers

Micro and nano Bi2O3 filled epoxy composites: Thermal, mechanical and γ-ray attenuation properties.

Sodium alginate/bismuth (III) oxide composites for γ‐ray shielding applications

X-Ray and γ-Ray Shielding Efficiency of Polymer Composites: Choice of Fillers, Effect of Loading and Filler Size, Photon Energy and Multifunctionality

Effective atomic number and electron density of some biologically important lipids for electron, proton, alpha particle and photon interactions

A simple software for swift computation of photon and charged particle interaction parameters: PAGEX.