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991.
992.
Characterisation of Hepatitis C virus (HCV)-specific CD8+ T-cell responses in the context of multiple HCV exposures is critical to identify broadly protective immune responses necessary for an effective HCV vaccine against the different HCV genotypes. However, host and viral genetic diversity complicates vaccine development. To compensate for the observed variation in circulating autologous viruses and host molecules that restrict antigen presentation (human leucocyte antigens; HLA), this study used a reverse genomics approach that identified sites of viral adaptation to HLA-restricted T-cell immune pressure to predict genotype-specific HCV CD8+ T-cell targets. Peptides representing these putative HCV CD8+ T-cell targets, and their adapted form, were used in individualised IFN-γ ELISpot assays to screen for HCV-specific T-cell responses in 133 HCV-seropositive subjects with high-risk of multiple HCV exposures. The data obtained from this study i) confirmed that genetic studies of viral evolution is an effective approach to detect novel in vivo HCV T-cell targets, ii) showed that HCV-specific T-cell epitopes can be recognised in their adapted form and would not have been detected using wild-type peptides and iii) showed that HCV-specific T-cell (but not antibody) responses against alternate genotypes in chronic HCV-infected subjects are readily found, implying clearance of previous alternate genotype infection. In summary, HCV adaptation to HLA Class I-restricted T-cell responses plays a central role in anti-HCV immunity and multiple HCV genotype exposure is highly prevalent in at-risk exposure populations, which are important considerations for future vaccine design.  相似文献   
993.
Satellite telemetry data are a key source of animal distribution information for marine ecosystem management and conservation activities. We used two decades of telemetry data from the East Antarctic sector of the Southern Ocean. Habitat utilization models for the spring/summer period were developed for six highly abundant, wide‐ranging meso‐ and top‐predator species: Adélie Pygoscelis adeliae and emperor Aptenodytes forsteri penguins, light‐mantled albatross Phoebetria palpebrata, Antarctic fur seals Arctocephalus gazella, southern elephant seals Mirounga leonina, and Weddell seals Leptonychotes weddellii. The regional predictions from these models were combined to identify areas utilized by multiple species, and therefore likely to be of particular ecological significance. These areas were distributed across the longitudinal breadth of the East Antarctic sector, and were characterized by proximity to breeding colonies, both on the Antarctic continent and on subantarctic islands to the north, and by sea‐ice dynamics, particularly locations of winter polynyas. These areas of important habitat were also congruent with many of the areas reported to be showing the strongest regional trends in sea ice seasonality. The results emphasize the importance of on‐shore and sea‐ice processes to Antarctic marine ecosystems. Our study provides ocean‐basin‐scale predictions of predator habitat utilization, an assessment of contemporary habitat use against which future changes can be assessed, and is of direct relevance to current conservation planning and spatial management efforts.  相似文献   
994.
995.
A novel series of CCR5 antagonists were identified based on the redesign of Schering C. An SAR was established based on inhibition of CCR5 (RANTES) binding and these compounds exhibited potent inhibition of R5 HIV-1 replication in peripheral blood mononuclear cells.  相似文献   
996.

Background

Collaborative care is an effective treatment for the management of depression but evidence on its cost-effectiveness in the UK is lacking.

Aims

To assess the cost-effectiveness of collaborative care in a UK primary care setting.

Methods

An economic evaluation alongside a multi-centre cluster randomised controlled trial comparing collaborative care with usual primary care for adults with depression (n = 581). Costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICER) were calculated over a 12-month follow-up, from the perspective of the UK National Health Service and Personal Social Services (i.e. Third Party Payer). Sensitivity analyses are reported, and uncertainty is presented using the cost-effectiveness acceptability curve (CEAC) and the cost-effectiveness plane.

Results

The collaborative care intervention had a mean cost of £272.50 per participant. Health and social care service use, excluding collaborative care, indicated a similar profile of resource use between collaborative care and usual care participants. Collaborative care offered a mean incremental gain of 0.02 (95% CI: –0.02, 0.06) quality-adjusted life-years over 12 months, at a mean incremental cost of £270.72 (95% CI: –202.98, 886.04), and resulted in an estimated mean cost per QALY of £14,248. Where costs associated with informal care are considered in sensitivity analyses collaborative care is expected to be less costly and more effective, thereby dominating treatment as usual.

Conclusion

Collaborative care offers health gains at a relatively low cost, and is cost-effective compared with usual care against a decision-maker willingness to pay threshold of £20,000 per QALY gained. Results here support the commissioning of collaborative care in a UK primary care setting.  相似文献   
997.
Intravenous administration of 10 to 40 U/g b.w. glucose oxidase produced hypoglycaemia in a dose-dependent manner. The enzyme-induced drop of the blood sugar level was associated with significant rise in serum potassium and the concentration of free fatty acids. Intracerebral application of glucose oxidase through chronically implanted cannula into the ventromedial, lateral hypothalamus, preoptic region and amygdaloid complex of nuclei failed to change the blood sugar level, although a moderate increase of the free fatty acids and corticosterone concentrations occurred. The local application of enzyme in the locus coeruleus region led to a significant rise of the blood sugar concentration. The observations suggest the sensitivity of brainstem catecholaminergic neuronal system to hypoglycaemia.  相似文献   
998.
We have investigated a proteinase inhibitor, designed according to the preferred amino acid sequence that is cleaved by the murine T-cell specific serine proteinase 1 (TSP-1) for its effect on the cytolytic potential of cloned cytotoxic T-cell lines (CTLL) and of cytoplasmic granules, derived from these cells. Pretreatment of effector cells with H-D-Pro-Phe-Arg-chloromethyl-ketone (PFR-CK) prior to the cytotoxicity assay did not result in inhibition of cytolytic activity of three independent CTLL and did not effect their granule-associated TSP-1 activity after extraction with Triton X-100. Furthermore, PFR-CK did not interfere with cytolysis of target cells by CTLL when present for the entire incubation period. In contrast, PFR-CK inhibited in a dose-dependent manner both TSP-1 activity and the hemolytic/cytolytic potential of isolated cytoplasmic granules after their pretreatment with high-salt concentration. We interpret these results to mean that cytolysis of target cells by CTLL involves the granule-associated proteinase TSP-1, which probably becomes active upon exocytosis following effector-target cell interactions.  相似文献   
999.
1000.
Genetic control of maturity in Tetrahymena pyriformis   总被引:4,自引:0,他引:4  
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