factors such as oxidative stress and reduced acetylcholine level have been implicated in alzheimer’s disease (ad) pathology and recently there has been a trend towards natural product research to find potential sources of antioxidants and acetylcholinesterase inhibitors in the plants kingdom. centaurea is a genus with about 500 species world wild, many of them have shown to possess biologic act...

inhibitor development is a lifelong challenge for patients with bleeding disorders who received replacement therapy. most commonly, inhibitor formation was observed in hemophilia a patients but patients with rare bleeding disorders (rbd) especially patients with deficiency of factor xiii (fxiii) and factor v (fv) can develop an inhibitor against exogenous factors. several factors considered as ...

Indoleamine 2,3-dioxygenase (IDO) is an important new therapeutic target for the treatment of cancer. With the aim of discovering novel IDO inhibitors, a virtual screen was undertaken and led to the discovery of the keto-indole derivative 1a endowed with an inhibitory potency in the micromolar range. Detailed kinetics were performed and revealed an uncompetitive inhibition profile. Preliminary ...

We examined the effect of adriamycin on kinetics of DNA synthesis catalyzed by DNA polymerase purified from bacteriophage T4-infected Escherichia coli. Two distinct modes of enzyme inhibition occur: uncompetitive and competitive at “low” and “high” drug:DNA nucleotide molar ratios, respectively. Competitive inhibition is not observed unless an unblocked amino group is present on the sugar (daun...

Pretreatment with an uncompetitive NMDA receptor antagonist, dizocilpine [( + )MK-801; six daily injections of 0.1 or 0.2 mg/kg, i.p.] significantly enhanced subsequent 1.5 g/kg ethanol-induced conditioned taste aversion (CTA). In a control experiment, dizocilpine (0.05-0.2 mg/kg) produced only a marginal CTA. Thus, pre-exposure to low, non-aversive doses of MK-801 may sensitize rats to the ave...

Diabetes mellitus is a multifactorial metabolic disease characterized by post-prandial hyperglycemia (PPHG). α-amylase and α-glucosidase inhibitors aim to explore novel therapeutic agents. Herein we report the promises of Dioscorea bulbifera and its bioactive principle, diosgenin as novel α-amylase and α-glucosidase inhibitor. Among petroleum ether, ethyl acetate, methanol and 70% ethanol (v/v)...

The synthesis and isolation of two derivatives of 2-amino-1,3,4-thialdiazole(aminothiadiazole) are described. The derivatives are a nicotinamide adenine dinucleotide (NAD) analog prepared by an exchange reaction with NAD in the presence of nicotineamide adenine dinucleotide glycohydrolase and a presumed aminothiadiazole mononucleotide prepared by treatment of the NAD analog with nucleotide pyro...

Previous studies in an acid-sulfate-chloride spring in Yellowstone National Park found that microbial arsenite [As(III)] oxidation is absent in regions of the spring outflow channel where H(2)S exceeds approximately 5 microM and served as a backdrop for continued efforts in the present study. Ex situ assays with microbial mat samples demonstrated immediate As(III) oxidation activity when H(2)S ...

Protoporphyrin IX ferrochelatase (EC 4.99.1.1) catalyzes the terminal step in the heme biosynthetic pathway, the insertion of ferrous iron into protoporphyrin IX. Ferrochelatase shows specificity, in vitro, for multiple metal ion substrates and exhibits substrate inhibition in the case of zinc, copper, cobalt, and nickel. Zinc is the most biologically significant of these; when iron is depleted...

Mouse glutathione S-transferase GST YfYf (an orthologue of GST P or 7-7 in the rat and of GST pi in the human) was found to have a subunit Mr of 24,500 and cross-reacted with anti-(rat GST YfYf). N-Terminal analysis showed a close similarity to the rat, human and bovine orthologues. On isoelectric focusing the native enzyme had a pI of 8.3 and a pI of 7.3 in the presence of urea. Initial-rate s...