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961.
962.
Richard F. Shore Mark A. Taggart Judit Smits Rafael Mateo Ngaio L. Richards Steve Fryday 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2014,369(1656)
Pharmaceuticals are highly bioactive compounds now known to be widespread environmental contaminants. However, research regarding exposure and possible effects in non-target higher vertebrate wildlife remains scarce. The fate and behaviour of most pharmaceuticals entering our environment via numerous pathways remain poorly characterized, and hence our conception and understanding of the risks posed to wild animals is equally constrained. The recent decimation of Asian vulture populations owing to a pharmaceutical (diclofenac) offers a notable example, because the exposure route (livestock carcasses) and the acute toxicity observed were completely unexpected. This case not only highlights the need for further research, but also the wider requirement for more considered and comprehensive ‘ecopharmacovigilance’. We discuss known and potential high risk sources and pathways in terrestrial and freshwater ecosystems where pharmaceutical exposure in higher vertebrate wildlife, principally birds and mammals, may occur. We examine whether approaches taken within existing surveillance schemes (that commonly target established classes of persistent or bioaccumulative contaminants) and the risk assessment approaches currently used for pesticides are relevant to pharmaceuticals, and we highlight where new approaches may be required to assess pharmaceutical-related risk. 相似文献
963.
Orthogonally protected l-threo-β-ethoxyasparagine (Fmoc-EtOAsn(Trt)-OH, 1) was synthesized from diethyl (2S,3S)-2-azido-3-hydroxysuccinate 2 in eight steps as a building block for solid-phase peptide synthesis. The starting material is easily available in multi-gram
scale from d-diethyltartrate. The transformation steps reported here are robust and scalable. Thus, a significant amount of 1 (1.8 g) was obtained in 21% overall yield. The synthesis reported is also expected to be useful for the preparation of other
O-substituted l-threo-β-hydroxyasparagine derivatives. 相似文献
964.
965.
Péter Degrell Judit Cseh Márton Mohás Gergő A. Molnár László Pajor John C. Chatham Norbert Fülöp István Wittmann 《Life sciences》2009,84(13-14):389-393
AimsThere is increasing evidence that O-linked N-acetylglucosamine (O-GlcNAc) plays an important role in cell signaling pathways. It has also been reported that increases in O-GlcNAc contribute to the development of diabetes and diabetic complications; however, little is known about O-GlcNAc levels in diabetic nephropathy (DNP). Therefore the goal of this study was to determine whether O-GlcNAc could be detected in human kidney biopsy specimens, and if so to examine whether O-GlcNAc levels were increased in the kidneys of patients with DNP compared to the non-diabetic individuals.Main methodsKidney biopsy specimens were obtained from type-2 diabetic patients (n = 6) and patients diagnosed with thin basement membrane nephropathy (n = 7) were used as non-diabetic controls. O-GlcNAc levels were assessed by immunohistochemistry using the anti-O-GlcNAc antibody CTD110.6.Key findingsWe show that O-GlcNAc modification of proteins can be detected in the human kidney biopsy specimens. Furthermore, in diabetic patients, we found significantly increased numbers of O-GlcNAc positive cells in the glomeruli and significantly elevated staining in the tubuli (both in the nucleus and in the cytosol). In addition we also observed an intense, granular O-GlcNAc staining specifically in diabetic tubuli.SignificanceIn light of the increase in O-GlcNAc staining in the diabetic patients, we propose that increased O-GlcNAc levels might contribute to the development of diabetic nephropathy. 相似文献
966.
967.
During a survey of methylotrophic yeasts in natural habitats in Hungary, the yeast community associated with the exudates of white poplar ( Populus alba ) was found to be unique among the tree exudates hitherto investigated. Nineteen methanol-assimilating yeast strains representing an undescribed ascomycetous species were isolated from tree exudates of P. alba collected at different locations in Hungary. Analysis of the D1/D2 large subunit rRNA gene sequences placed the strains in the Ogataea clade and the new species is described as Ogataea populialbae . The type culture is NCAIM Y.01853T (CBS 11363, NRRL Y-48632). 相似文献
968.
969.
Abstract Protoplasts from auxotrophic mutants of Candida albicans and Candida tropicalis were produced by snail enzyme treatment and their fusion was induced with polyethylene glycol (PEG). During selective regeneration, nutritionally complemented interspecific hybrids were obtained. Their cells contained one nucleus, and the DNA content per cell was higher than in the parents. The isoenzymic and sugar assimilation patterns of the mutants, and those of the hybrids and the products after their haploidisation, were also analysed. The results indicated that the hybrids were partial alloploids containing the total chromosomal set of either of the parental species and one or a few chromosomes of the other. 相似文献
970.
Shakeri Abolfazl Hafezian Toktam Kúsz Norbert Hohmann Judit Boozari Motahare Mottaghipisheh Javad Emami Seyed Ahmad Tayarani-Najaran Zahra Asili Javad 《Molecular biology reports》2022,49(9):8251-8258
Molecular Biology Reports - Cytotoxic activities of methanolic crude extract of Stachys parviflora (Lamiaceae family) and its sub-fractions were primarily evaluated against human breast... 相似文献