Bioaccumulation of Polychlorinated Biphenyls (PCBs) in Atlantic Sea Bream (Archosargus rhomboidalis) from Kingston Harbour, Jamaica.

Multiple sizes of Sea bream were collected from Kingston Harbour, Jamaica, to assess steady state bioaccumulation of polychlorinated biphenyls (PCBs) in a tropical fish. Sea beam fork lengths ranged from 7.3 to 21.

The effects of S-nitrosoglutathione and S-nitroso-N-acetyl-D, L-penicillamine in a rat model of pre-eclampsia.

Background: Pre-eclampsia (PE) complicates approximately 5-7% of all pregnancies. This study investigates the effects of S-nitroso-N-acetylpenicillamine (SNAP) and S-nitrosoglutathione (GSNO) on the classical features of PE.

Materials And Methods: On day 14 of gestation, female Sprague-Dawley rats were separated into five groups and treated intravenously for 7 days as follows: (i) 0.

Acrylamide in Caribbean foods - residual levels and their relation to reducing sugar and asparagine content.

The acrylamide levels in commercial and homemade Caribbean foods were determined by pre-derivatisation of acrylamide to 2-bromopropenamide and analysed by gas chromatography with mass spectrometric (GC/MS) detection. Over 100 Caribbean food samples were analysed for the presence of acrylamide. These samples include: biscuits, breakfast cereals, banana chips and home-prepared foods: breadfruit; Artocarpus altilis, banana fritters, and dumplings.

The effect of nitric oxide inhibitors and Snitroso-Nacetylpenicillamine on glucose concentration in an animal model.

Background: Nitric oxide (NO) is becoming an increasingly important signaling molecule implicated in a growing number of physiological and pathophysiological processes. Research on the effect of NO donors on glucose metabolism in peripheral tissues have grown rapidly in the last decade. This study examined the effects of N(G)methyl-L-arginine acetate (L-NMMA) and N(G)methyl-L-arginine ester (L-NAME) on fasting and postprandial blood glucose concentrations.

Dynamic studies of transnitrosation of thiols of biological importance by the nitrosated 4,4',4'',4'''-tetrasulfophthalocyaninecobaltate(III) anion in aqueous solution.

The kinetics of interaction of Co(III)TSPcNO (TSPc = 4,4',4'',4'''-tetrasulfophthalocyanine) with various thiols of biological relevance, e.g., reduced glutathione (GSH), captopril (CapSH), N-acetyl-L-cysteine (NALC), and L-cysteine ethyl ester (LCEE) have been investigated spectrophotometrically.

Transfer of nitric oxide from nitrovasodilators to free thiols--evidence of two distinct stages.

Two distinct stages, which can be monitored spectrophotometrically, have been observed for the first time in multiple reactions between thiol, such as l-cysteine and some well-known nitrovasodilators, namely S-nitroso-N-acetyl-d,l-penicillamine (SNAP), S-nitrosoglutathione (GSNO), and S-nitrosocaptopril (SNOCap) in aqueous solution (in the presence of EDTA). The first part of the reaction occurs at stopped-flow time scale ( approximately 10(-2)s(-1)) in one single step and has been found to be transnitrosation; followed by a slow decomposition of the products of the transnitrosation reaction with the formation of a variety of nitrogen products. Reactivity with regard to the first stage occurs in the order GSNO>SNAP>SNOCap.

The reaction of S-nitroso-N-acetyl-D,L-penicillamine (SNAP) with the angiotensin converting enzyme inhibitor, captopril--mechanism of transnitrosation.

Kinetic studies involving the use of both stopped-flow and diode array spectrophotometers, show that the reaction between SNAP and captopril in the presence of the metal ion sequestering agent, EDTA, occurs in two well-defined stages. The first stage is a fast reaction while the second stage is slow. The first stage has been postulated to be transnitrosation, and the second stage involves the decay of the newly formed RSNO to effect nitric oxide (NO) release.

The effect of nitric oxide on glucose metabolism.

Nitric oxide (NO) is an important bioactive signaling molecule that mediates a variety of normal physiological functions, which, if altered, could contribute to the genesis of many pathological conditions, including diabetes. In this study, we examined the possible diabetogenicity of NO by noting differences in the cellular binding of insulin in dogs treated with the NO donor, S-nitrosoglutathione (GSNO) compared to captopril-treated controls. GSNO administration resulted in an abnormality in glucose metabolism which was attributed to decreased binding of insulin to its receptor on the cell membrane of mononuclear leucocytes, 11.

The effect of nitric oxide on glucose metabolism.

Nitric oxide (NO) is an important bioactive signaling molecule that mediates a variety of normal physiological functions, which, if altered, could contribute to the genesis of many pathological conditions, including diabetes. In this study, we examined the possible diabetogenicity of NO by noting differences in the cellular binding of insulin in dogs treated with the NO donor, S-nitrosoglutathione (GSNO) compared to captopril-treated controls. GSNO administration resulted in an abnormality in glucose metabolism which was attributed to decreased binding of insulin to its receptor on the cell membrane of mononuclear leucocytes, 11.

Dynamics of interaction of vitamin C with some potent nitrovasodilators, S-nitroso-N-acetyl-d,l-penicillamine (SNAP) and S-nitrosocaptopril (SNOCap), in aqueous solution.

The reductive decomposition of both SNAP and SNOCap by ascorbate in aqueous solution (in the presence of EDTA) was thoroughly investigated. Nitric oxide (NO) release from the reaction occurs in an ascorbate concentration and pH dependent manner. Rates and hence NO release increased drastically with increasing pH, signifying that the most highly ionized form of ascorbate is the more reactive species.

The enhancement of the hyperglycemic effect of S-nitrosoglutathione and S-nitroso-N-acetylpenicillamine by vitamin C in an animal model.

Background: S-nitrosoglutathione (GSNO) and S-nitroso-N-acetlypenicillamine (SNAP) are two of the most common sources of nitric oxide (NO) in the biomedical field. Vitamin C has been known to accelerate the decomposition of GSNO and SNAP increasing the release and availability of NO which is cytotoxic at non-physiological concentrations. The study investigates any potential detrimental effect of vitamin C and GSNO, vitamin C and SNAP on glucose metabolism in normotensive and normoglycemic dogs.

Decreased insulin binding to mononuclear leucocytes and erythrocytes from dogs after S-nitroso-N-acetypenicillamine administration.

Background: Nitric oxide (NO) and oxygen free-radicals play an important part in the destruction of beta-cells in auto- immune diabetes although the precise mechanism of interaction is still not known. This study was designed to examine any possible diabetogenic effect of NO by investigating any differences in cellular binding of insulin to its receptor on the cell membranes of erythrocytes and mononuclear leucocytes of dogs treated with the NO donor, S-nitroso-N-acetylpenicillamine (SNAP) and controls treated with captopril.

Results: The result obtained showed decreased binding of insulin to its receptor on the cell membranes of erythrocytes and mononuclear leucocytes.