Biomedical activity

Recently, research on the biomedical activity of pu-erh tea has focused on its antibacterial, antioxidative, lipid-lowering, and antiobesity effects. Many in vitro studies have shown that pn-erh tea has antioxidative activity. Lin et al. reported that the water extract of pn-erh tea (100 pg/ml) can protect the plasmid DNA from strand breakage indnced by the Fenton reaction as well as the control, regardless of total catechin content. Dnh et al reported that pn-erh tea water extract with less cat-echins (8.01 mg/ml), compared to green tea water extract with more catechins (79.1 mg/ml), could still chelate metal ions, scavenge DPPH radicals, and decrease nitric oxide production in lipopolysaccharide-activated RAW 264.7 macrophages. 

Kumirska, J., Weinhold, M.X., Thoming, J. and Stepnowski, P. (2011) Biomedical activity of chitin/ chitosan based materials - influence of physicochemical properties apart from molecular weight and degree of N-acetylation. Polymers, 3, 1875-1901. 

Rybolt et al. studied the adsorption of a biomedically active aromatic compound acetaminophen, which is the active constituent of Tylenol, and an aUphalic compound N-acetylcysteine, which is an antidote for acetaminophen overdose on an activated carbon from aqueons solutions at gastric pH 1.2 and intestinal pH 7.0. The adsorption data fitted the Langmuir isotherm equation for both the adsorbates. 

J. Kumirska, M.X. Weinhold, M. Czerwicka, Z. Kaczynski, A. Bychowska, K. Brzozowski, J. Thoming, P. Stepnowski, Influence of the chemical structure and physicochemical properties of chitin- and chitosan-based materials on their biomedical activity in A.N. Laskovski, ed.. Biomedical Engineering Trends in Materials Science-, InTech Rijeka, Croatia, pp. 25-64,2011. F. Gandia-Herrero, J. Cabanes, J. Escribano, F. Garda-Carmona,M. JimenezAtienzar, Encapsulation of the most potent antioxidant betalains in edible matrixes as powders of different colors, /. Agr. Food Chem., 61,4294-4302, 2013.. 

Alkenylsuccinic anhydrides made from several linear alpha olefins are used in paper sizing, detergents, and other uses. Sulfosuccinic acid esters serve as surface active agents. Alkyd resins (qv) are used as surface coatings. Chlorendric anhydride [115-27-5] is used as a flame resistant component (see Flame retardants). Tetrahydrophthalic acid [88-98-2] and hexahydrophthalic anhydride [85-42-7] have specialty resin appHcations. Gas barrier films made by grafting maleic anhydride to polypropylene [25085-53-4] film are used in food packaging (qv). Poly(maleic anhydride) [24937-72-2] is used as a scale preventer and corrosion inhibitor (see Corrosion and corrosion control). Maleic anhydride forms copolymers with ethylene glycol methyl vinyl ethers which are partially esterified for biomedical and pharmaceutical uses (189) (see Pharmaceuticals). 

Other biomedical and biological appHcations of mictocapsules continue to be developed. For example, the encapsulation of enzymes continues to attract interest even though loss of enzyme activity due to harshness of the encapsulation protocols used has been a persistent problem (59). The use of mictocapsules in antibody hormone immunoassays has been reviewed (60). The encapsulation of hemoglobin as a ted blood substitute has received much attention because of AIDS and blood transfusions (61). 

Biomedical Uses. The molybdate ion is added to total parenteral nutrition protocols and appears to alleviate toxicity of some of the amino acid components in these preparations (see Mineral NUTRIENTS) (97). Molybdenum supplements have been shown to reduce iiitrosarnine-induced mammary carcinomas in rats (50). A number of studies have shown that certain heteropolymolybdates (98) and organometaUic molybdenum compounds (99) have antiviral, including anti-AIDS, and antitumor activity (see Antiviral agents Chemotherapeutics, anticancer). 

Radiation grafting for various biomedical applications remains an extremely active field of development. The grafted side chains can contain functional groups to which bioactive materials can be attached. These include amine, carboxylic, and hydroxyl groups, which can be considered as a center for further modifications. 

Biomedical materials include ceramics such as the biologically active hydroxylapatite and tricalcium phosphate, and high-strength metals such as titanium alloys.These materials are not produced by CVD as this time, except on an experimental basis. CVD, however, is the major process used in the production of another very important biomedical material, i.e., isotropic... 

Wyn Jones, R.G., Storey, R., Leigh, R.A., Ahamad, N. Pollard, A. (1977). A hypothesis of cytoplasmic osmoregulation. In Regulation of Cell Membrane Activities in Plants, ed. E. Marre and O. Ciferri, pp. 121-36. Amsterdam Elsevier/North Holland Biomedical Press. 

Materials. I-EGF was either made by iodinating mouse EGF (Biomedical Technologies Inc.) by the chloramine T method, to a specific activity of approximately 1-2 Ci/ xmol, using Na- I (Amersham) or purchased from New England Nuclear. Phorbol diterpene esters were purchased from Sigma. Palytoxin was isolated from Palythoa tuberculosa as previously described (1). 

Magee, P.N. in de Serres, F.J., Fouts, J.R., Bend, J.R. and Philpot, R.M. (eds), In Vitro Metabolic Activation in Mutagenesis Testing , Elsevier/North Holland Biomedical Press, Amsterdam, 1976 pp. 213-216. 

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