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The lead optimisation of the diaminopyrimidine carboxamide series of spleen tyrosine kinase inhibitors is described. The medicinal chemistry strategy was focused on optimising the human whole blood activity whilst achieving a sufficient margin over liability kinases and hERG activity. GSK143 is a potent and highly selective SYK inhibitor showing good efficacy in the rat Arthus model.  相似文献   
125.
There is a wide inter-individual variation in PARP-1 {PAR [poly(ADP-ribose)] polymerase 1} activity, which may have implications for health. We investigated if the variation: (i) is due to polymorphisms in the PARP-1 gene or PARP-1 protein expression; and (ii) affects patients' response to anticancer treatment. We studied 56 HV (healthy volunteers) and 118 CP (cancer patients) with supporting in vivo experiments. PARP activity ranged between 10 and 2600 pmol of PAR/106 cells and expression between 0.02-1.55 ng of PARP-1/μg of protein. PARP-1 expression correlated with activity in HV (R2=0.19, P=0.003) and CP (R2=0.06, P=0.01). A short CA repeat in the promoter was significantly associated with increased cancer risk [OR (odds ratio), 5.22; 95% CI (confidence interval), 1.79-15.24]. PARP activity was higher in men than women (P=0.04) in the HV. Male mice also had higher PARP activity than females or castrated males. Oestrogen supplementation activated PARP in PBMCs (peripheral blood mononuclear cells) from female mice (P=0.003), but inhibited PARP-1 in their livers by 80%. PARP activity and expression were not dependent on the investigated polymorphisms, but there was a modest correlation of PARP activity with expression. Studies in the HV revealed sex differences in PARP activity, which was confirmed in mice and shown to be associated with sex hormones. Toxic response to treatment was not associated with PARP activity and/or expression.  相似文献   
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Long-term monitoring of reintroduced individuals is a central component of many endangered species reintroduction programs. Radio-telemetry techniques are rarely used to monitor reintroduced captive-bred Cracids and few data exist regarding possible adverse effects of radio-tagging Cracids. In this study, we identify an appropriate radio transmitter design and develop a suitable attachment method that minimizes anthropogenic influence and enables long-term, post-release monitoring (2–3 years) of reintroduced captive-bred Red-billed Curassows in the Brazilian Atlantic Rainforest. We also review studies about the effects of different VHF radio transmitter models on survival, reproduction, behavior, and physiology of Galliformes.  相似文献   
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We report the development of a rapid chromatographic method for the isolation of bacterial ribosomes from crude cell lysates in less than ten minutes. Our separation is based on the use of strong anion exchange monolithic columns. Using a simple stepwise elution program we were able to purify ribosomes whose composition is comparable to those isolated by sucrose gradient ultracentrifugation, as confirmed by quantitative proteomic analysis (iTRAQ). The speed and simplicity of this approach could accelerate the study of many different aspects of ribosomal biology.  相似文献   
128.
We attempt to quantify how significant the polar archipelago of South Georgia is as a source of regional and global marine biodiversity. We evaluate numbers of rare, endemic and range-edge species and how the faunal structure of South Georgia may respond to some of the fastest warming waters on the planet. Biodiversity data was collated from a comprehensive review of reports, papers and databases, collectively representing over 125 years of polar exploration. Classification of each specimen was recorded to species level and fully geo-referenced by depth, latitude and longitude. This information was integrated with physical data layers (e.g. temperature, salinity and flow) providing a visualisation of South Georgia's biogeography across spatial, temporal and taxonomic scales, placing it in the wider context of the Southern Hemisphere. This study marks the first attempt to map the biogeography of an archipelago south of the Polar Front. Through it we identify the South Georgian shelf as the most speciose region of the Southern Ocean recorded to date. Marine biodiversity was recorded as rich across taxonomic levels with 17,732 records yielding 1,445 species from 436 families, 51 classes and 22 phyla. Most species recorded were rare, with 35% recorded only once and 86% recorded <10 times. Its marine fauna is marked by the cumulative dominance of endemic and range-edge species, potentially at their thermal tolerance limits. Consequently, our data suggests the ecological implications of environmental change to the South Georgian marine ecosystem could be severe. If sea temperatures continue to rise, we suggest that changes will include depth profile shifts of some fauna towards cooler Antarctic Winter Water (90-150 m), the loss of some range-edge species from regional waters, and the wholesale extinction at a global scale of some of South Georgia's endemic species.  相似文献   
129.
Aphids are major agricultural pests that cause significant yield losses of crop plants each year.Excessive dependence on insec-ticides for long-term aphid control is undesirable because of the development of insecticide resistance,the potential negative effects on non-target organisms and environmental pollution.Transgenic crops engineered for resistance to aphids via a non-toxic mode of action could be an efficient alternative strategy.(E)-β-Farnesene (EβF) synthases catalyze the formation of EβF,which for many pest aphids is the main component of the alarm pheromone involved in the chemical communication within these species.EβF can also be synthesized by certain plants but is then normally contaminated with inhibitory compounds.Engineering of crop plants capable of synthesizing and emitting EβF could cause repulsion of aphids and also the attraction of natural enemies that use EβF as a foraging cue,thus minimizing aphid infestation.In this review,the effects of aphids on host plants,plants' defenses against aphid herbivory and the recruitment of natural enemies for aphid control in an agricultural setting are briefly introduced.Furthermore,the plant-derived EβF synthase genes cloned to date along with their potential roles in generating novel aphid resistance via genetically modified approaches are discussed.  相似文献   
130.
Lack of genomic sequence data and the relatively high cost of tandem mass spectrometry have hampered proteomic investigations into helminths, such as resolving the mechanism underpinning globally reported anthelmintic resistance. Whilst detailed mechanisms of resistance remain unknown for the majority of drug-parasite interactions, gene mutations and changes in gene and protein expression are proposed key aspects of resistance. Comparative proteomic analysis of drug-resistant and -susceptible nematodes may reveal protein profiles reflecting drug-related phenotypes. Using the gastro-intestinal nematode, Haemonchus contortus as case study, we report the application of freely available expressed sequence tag (EST) datasets to support proteomic studies in unsequenced nematodes. EST datasets were translated to theoretical protein sequences to generate a searchable database. In conjunction with matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF-MS), Peptide Mass Fingerprint (PMF) searching of databases enabled a cost-effective protein identification strategy. The effectiveness of this approach was verified in comparison with MS/MS de novo sequencing with searching of the same EST protein database and subsequent searches of the NCBInr protein database using the Basic Local Alignment Search Tool (BLAST) to provide protein annotation. Of 100 proteins from 2-DE gel spots, 62 were identified by MALDI-TOF-MS and PMF searching of the EST database. Twenty randomly selected spots were analysed by electrospray MS/MS and MASCOT Ion Searches of the same database. The resulting sequences were subjected to BLAST searches of the NCBI protein database to provide annotation of the proteins and confirm concordance in protein identity from both approaches. Further confirmation of protein identifications from the MS/MS data were obtained by de novo sequencing of peptides, followed by FASTS algorithm searches of the EST putative protein database. This study demonstrates the cost-effective use of available EST databases and inexpensive, accessible MALDI-TOF MS in conjunction with PMF for reliable protein identification in unsequenced organisms.  相似文献   
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