Chitosan Modification and Pharmaceutical/Biomedical Applications

Chitosan has received much attention as a functional biopolymer for diverse applications, especially in pharmaceutics and medicine. Our recent efforts focused on the chemical and biological modification of chitosan in order to increase its solubility in aqueous solutions and absorbability in the in vivo system, thus for a better use of chitosan. This review summarizes chitosan modification and its pharmaceutical/biomedical applications based on our achievements as well as the domestic and overseas developments: (1) enzymatic preparation of low molecular weight chitosans/chitooligosaccharides with their hypocholesterolemic and immuno-modulating effects; (2) the effects of chitin, chitosan and their derivatives on blood hemostasis; and (3) synthesis of a non-toxic ion ligand—D-Glucosaminic acid from Oxidation of D-Glucosamine for cancer and diabetes therapy

Development of method for evaluating cell hardness and correlation between bacterial spore hardness and durability

<p>Abstract</p> <p>Background</p> <p>Despite the availability of conventional devices for making single-cell manipulations, determining the hardness of a single cell remains difficult. Here, we consider the cell to be a linear elastic body and apply Young’s modulus (modulus of elasticity), which is defined as the ratio of the repulsive force (stress) in response to the applied strain. In this new method, a scanning probe microscope (SPM) is operated with a cantilever in the “contact-and-push” mode, and the cantilever is applied to the cell surface over a set distance (applied strain).</p> <p>Results</p> <p>We determined the hardness of the following bacterial cells: <it>Escherichia coli</it>, <it>Staphylococcus aureus</it>, <it>Pseudomonas aeruginosa</it>, and five <it>Bacillus</it> spp. In log phase, these strains had a similar Young’s modulus, but <it>Bacillus</it> spp. spores were significantly harder than the corresponding vegetative cells. There was a positive, linear correlation between the hardness of bacterial spores and heat or ultraviolet (UV) resistance.</p> <p>Conclusions</p> <p>Using this technique, the hardness of a single vegetative bacterial cell or spore could be determined based on Young’s modulus. As an application of this technique, we demonstrated that the hardness of individual bacterial spores was directly proportional to heat and UV resistance, which are the conventional measures of physical durability. This technique allows the rapid and direct determination of spore durability and provides a valuable and innovative method for the evaluation of physical properties in the field of microbiology.</p

Improvement of permeability of sintering bed by quasi-granulation

35.00; Translated from Japanese (Tetsu To Hagane 1985 v. 71(10) p. A177-A180)Available from British Library Document Supply Centre- DSC:9022.06(BISI-Trans--26715)T / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo