Curcumin (Cur) is a striking anticancer agent, but its low aqueous solubility, poor absorption, hasty metabolism, and elimination limit its oral bioavailability and consequently hinder its development as a drug. To redress these limitations, amphiphilic chitosan (CS) conjugate with improved mucoadhesion and solubility over a wider pH range was developed by modification with hydrophobic acryloni...

BACKGROUND Vasopressor agents are commonly used to increase mean arterial pressure (MAP) in order to secure a pressure gradient to perfuse vital organs. The influence of norepinephrine on cerebral oxygenation is not clear. The aim of this study was to evaluate the impact of the infusion of norepinephrine on cerebral oxygenation in healthy subjects. METHODS Three doses of norepinephrine (0.05,...

Pistachio yield are often negatively affected by some physiological problems such as abscission of inflorescence buds and fruits, deformed or blank nuts, and non-split shells. In the present study the effect of exogenous application of arginine (Arg) (a substrate for nitric oxide (NO) synthase) and sodium nitroproside (SNP), as a NO-donor was investigated on yield production, fruit and inflores...

Recent studies indicated that the Arg allele is preferentially mutated and retained in various human cancers arising in Pro/Arg heterozygotes and it may be an important biomarker in colon cancer prognosis. In this study, DNA was isolated from paraffine-embedded colon tumor tissue samples of 35 cases diagnosed as colon carcinoma. We have observed PCR-RFLP genotyping for the codon 72 exon 4 polym...

The objective of this experiment was to investigate the effect dietary supplementation arginine (Arg), tryptophan (Trp), and taurine (Tau) on productive performance, egg quality, liver visual characteristics, antioxidant status, immune response, stress indicator laying hens raised under heat conditions. A total two hundred eighty 47-wk-old Hy-Line Brown were randomly allotted 1 4 treatments wit...

L-Canavanine (CAV), the L-2-amino-4-guanidinooxy structural analogue of L-arginine (ARG), is a potent ARG antagonist which occurs in the jack bean, Canavalia ensiformis. This ARG antimetabolite is active against L1210 murine leukemia and a solid colonic tumor in the rat. Our initial studies using a microtiter assay show that CAV exhibits a 50% inhibitory concentration of approximately 2 mM agai...

It is commonly believed that the activity of NO synthase (NOS) solely controls NO production from its substrates, L-Arg and O(2). The Michaelis-Menten constant (K(m)) of NOS for L-Arg is in the micromolar range; cellular levels of L-Arg are much higher. However, evidence strongly suggests that cellular supply of L-Arg may become limiting and lead to reduced NO and increased superoxide anion (O(...

The exquisite selectivity and catalytic activity of enzymes have been shaped by the effects of positive and negative selection pressure during the course of evolution. In contrast, enzyme variants engineered by using in vitro screening techniques to accept novel substrates typically display a higher degree of catalytic promiscuity and lower total turnover in comparison with their natural counte...

Key enzymes of the urea cycle and (15)N-labeling patterns of arginine (Arg) were measured to elucidate the involvement of Arg in nitrogen translocation by arbuscular mycorrhizal (AM) fungi. Mycorrhiza was established between transformed carrot (Daucus carota) roots and Glomus intraradices in two-compartment petri dishes and three ammonium levels were supplied to the compartment containing the e...