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151.
The detection of 3-nitro-L-tyrosine residues associated with many disease states, including gastric cancer, has implicated a role for peroxynitrite in vivo, and thus endogenously produced nitric oxide and superoxide. Additionally, dietary nitrate has been suggested to be involved in the pathogenesis of gastric cancer through a mechanism involving reduction to nitrite and subsequent formation of potentially mutagenic nitrosocompounds. Studies have now demonstrated that a multitude of reactive nitrogen species other than peroxynitrite are capable of producing nitrotyrosine. Thus, we have reviewed the evidence that dietary nitrate, amongst other reactive nitrogen species, may contribute to the body burden of nitrotyrosine. 相似文献
152.
This research is focused on the antioxidant properties of dietary components, in particular phenolics and carotenoids and the assessment of the contribution of the combined antioxidants to the total antioxidant activity (TAA) of tomato fruit. The aim of this study was to analyse the effects of processing on the antioxidant properties of tomato. The effects of three different methods of processing fresh tomatoes into tomato sauce were investigated with respect to the antioxidant properties of the fruit. Identification and quantification of the main carotenoids and flavonoids present in tomatoes was achieved by HPLC analysis and the effect on the concentration and availability of these compounds was investigated at different stages of the processing. The processing affected mainly naringenin causing a reduction in the concentration. Conversely, levels of chlorogenic acid were increased suggesting an improvement in availability of this compound to extraction. The concentration of all- trans -lycopene was also increased following processing. Less than 10% isomerisation of all- trans -lycopene to the cis form was detected for all the methods analysed. The effects of processing on the overall antioxidant activity support the theory of a general improvement in availability of individual antioxidants. For both hydrophilic and lipophilic extracts TAA values were increased. 相似文献
153.
Gerbrand J. van der Heden van Noort Catherine H. Schein Herman S. Overkleeft Gijsbert A. van der Marel Dmitri V. Filippov 《Journal of peptide science》2013,19(6):333-336
Small proteins called viral protein genome‐linked (VPg), attached to the 5′‐end of the viral RNA genome are found as common structure in the large family of picornaviruses. The replication of these viruses is primed by this VPg protein linked to a single uridylyl residue. We report a general procedure to obtain such nucleoproteins employing a pre‐uridylylated tyrosine building block in an on‐line solid phase‐based approach. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
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155.
Susan C. Connor Mark P. Hodson Stephanie Ringeissen Brian C. Sweatman Paul J. Mcgill Catherine J. Waterfield 《Biomarkers》2013,18(4-5):364-385
A previous report of this work (Ringeissen et al. 2003) described the use of nuclear magnetic resonance (NMR) spectroscopy coupled with multivariate statistical data analysis (MVDA) to identify novel biomarkers of peroxisome proliferation (PP) in Wistar Han rats. Two potential biomarkers of peroxisome proliferation in the rat were described, N-methylnicotinamide (NMN) and N-methyl-4-pyridone-3-carboxamide (4PY). The inference from these results was that the tryptophan-nicotinamide adenine dinucleotide (NAD+) pathway was altered in correlation with peroxisome proliferation, a hypothesis subsequently confirmed by TaqMan® analysis of the relevant genes encoding two key enzymes in the pathway, aminocarboxymuconate-semialdehyde decarboxylase (EC 4.1.1.45) and quinolinate phosphoribosyltransferase (EC 2.4.2.19). The objective of the present study was to investigate these data further and identify other metabolites in the NMR spectrum correlating equally with PP. MVDA Partial Least Squares (PLS) models were constructed that provided a better prediction of PP in Wistar Han rats than levels of 4PY and NMN alone. The resulting Wistar Han rat predictive models were then used to predict PP in a test group of Sprague Dawley rats following administration of fenofibrate. The models predicted the presence or absence of PP (above on arbitrary threshold of >2-fold mean control) in all Sprague Dawley rats in the test group. 相似文献
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157.
Catherine Waldby 《New genetics and society》2013,32(1):19-31
Somatic cell nuclear transfer (SCNT) research, otherwise known as therapeutic cloning, requires large numbers of research oocytes, placing pressure on an already limited supply. In the UK, Canada, Australia, Singapore and most of Western Europe, oocytes are made available through modestly reimbursed donation, and, owing to the onerous nature of donation, the existing demand for reproductive oocytes far outstrips availability. SCNT research will place this system under even greater pressure. This paper investigates the growth in a global market for oocytes, where transnational IVF clinics broker sales between generally poor, female vendors and wealthy purchasers, beyond the borders of national regulation, and with little in the way of clinical or bioethical scrutiny. It considers the possible impact that SCNT research will have on this global market. It argues that oocyte vending could be understood as a kind of reproductive labor in the bioeconomy, and suggests some ways to improve the protection, security and power of vendors. 相似文献
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