1. Pepsin in solution at 38 degrees C. is most stable at a hydrogen ion concentration of about 10(-5) (pH 5.0). 2. Increasing the hydrogen ion concentration above pH 5.0 causes a slow increase in the rate of destruction of pepsin. 3. Decreasing the hydrogen ion concentration below pH 5.0 causes a very rapid increase in the rate of destruction of the enzyme. 4. Neither the purity of the enzyme s...

S. L. Shapiro and colleagues (2006) have described a testable theory of the mechanisms of mindfulness and how it affects positive change. They describe a model in which mindfulness training leads to a fundamental change in relationship to experience (reperceiving), which leads to changes in self-regulation, values clarification, cognitive and behavioral flexibility, and exposure. These four var...

A new methylated flavonol, 5,7,2',4'-tetrahydroxy-3-methoxyflavone (1), had been isolated from the methanol extract of the wood of Morus australis, along with nine known compounds, kuwanon C (2), morusin (3), morachalcone A (4), oxyresveratrol (5), 4'-(2-methyl-2-buten-4-yl)oxyresveratrol (6), moracins M (7) and C (8), alboctalol (9), and macrourin B (10). The structures of these compounds were...

Current knowledge of horseshoe crabs (HSC) has been derived, in large part, from field studies. Comprehending the biology and conservation of HSC could be facilitated and augmented by understanding and improving their culture methods. Althoughmany researchers and even lay people are capable of getting animals to the early stages of development, very few are successful in getting them to survive...

this study was carried out to evaluate the antimicrobial and antioxidant effectiveness of methanolic extract and different fractions (n-butanol, ethyl acetate, chloroform and n-hexane) of c.intybus seeds. the antimicrobial activity was determined by the disc diffusion method and minimum inhibitory concentration (mic) against a panel of microorganisms (four bacterial strains, i.e. p. multocida, ...

Two new 3-alkylpiperidine alkaloids, tetradehydrohalicyclamine A (2) and 22-hydroxyhalicyclamine A (3), have been isolated from a marine sponge Amphimedon sp. as cytotoxic constituents. Their structures were elucidated by spectroscopic analysis. Compounds 2 and 3 inhibited growth of P388 cells with IC50 values of 2.2 and 0.45 microg/mL, respectively.

Small peptide analogues representing the C-terminal portion of angiotensin I sequence were designed as inhibitors of human renin. Among synthesized compounds, benzyloxycarbonyl (-"Z")-(1-naphthyl)Ala-His-leucinal (ES-188), Z-(1-naphthyl)Ala-His-statine ethyl ester (ES-226), and Z-(1-naphthyl)Ala-His-statine 2-methylbutylamide (ES-254) markedly inhibited human and primate renins (inhibitory conc...

it seems that rapid destruction of gram negative bacteria by antibiotics contributes to the clinical deterioration of some patients with gram negative infections. antibiotics increase the concentration of lipopolysaccharide (lps) in blood and cerebrospinal fluids. released lps can activate blood cells to produce tumor necrosis factor-alpha (tnf-a) and other cytokines. tnf-a appears to be a majo...