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排序方式: 共有186条查询结果,搜索用时 875 毫秒
81.
Thijs Feuth Joop E. Arends Justin H. Fransen Nening M. Nanlohy Karel J. van Erpecum Peter D. Siersema Andy I. M. Hoepelman Debbie van Baarle 《PloS one》2013,8(3)
Objectives
To investigate whether T-cell activation and exhaustion is linked to HCV- and HIV disease parameters in HIV/HCV infected individuals, we studied T-cell characteristics in HIV/HCV coinfected patients and controls.Methods
14 HIV/HCV coinfected, 19 HCV monoinfected, 10 HIV monoinfected patients and 15 healthy controls were included in this cross-sectional study. Differences in expression of activation and exhaustion markers (HLA-DR, CD38, PD-1, Tim-3 and Fas) and phenotypic markers on CD4+ and CD8+ T-cells were analysed by flow cytometry and were related to HCV disease parameters (HCV-viremia, ALT and liver fibrosis).Results
Frequencies of activated CD4+ and CD8+ T-cells were higher in HIV/HCV-coinfected compared to healthy controls and HCV or HIV mono-infected individuals. Coinfected patients also showed high expression of the exhaustion marker PD-1 and death receptor Fas. In contrast, the exhaustion marker Tim-3 was only elevated in HIV-monoinfected patients. T-cell activation and exhaustion were correlated with HCV-RNA, suggesting that viral antigen influences T-cell activation and exhaustion. Interestingly, increased percentages of effector CD8+ T-cells were found in patients with severe (F3–F4) liver fibrosis compared to those with no to minimal fibrosis (F0–F2).Conclusions
HIV/HCV coinfected patients display a high level of T-cell activation and exhaustion in the peripheral blood. Our data suggest that T-cell activation and exhaustion are influenced by the level of HCV viremia. Furthermore, high percentages of cytotoxic/effector CD8+ T-cells are associated with liver fibrosis in both HCV monoinfected and HIV/HCV coinfected patients. 相似文献82.
Vanessa K. Wong Derek J. Pickard Lars Barquist Karthikeyan Sivaraman Andrew J. Page Peter J. Hart Mark J. Arends Kathryn E. Holt Leanne Kane Lynda F. Mottram Louise Ellison Ruben Bautista Chris J. McGee Sally J. Kay Thomas M. Wileman Linda J. Kenney Calman A. MacLennan Robert A. Kingsley Gordon Dougan 《PloS one》2013,8(12)
83.
Objectives
Workers with common mental disorders (CMDs) frequently experience recurrent sickness absence but scientifically evaluated interventions to prevent recurrences are lacking. The objectives of this study are to evaluate the cost-effectiveness and cost-benefit of a problem solving intervention aimed at preventing recurrent sickness absence in workers with CMDs compared to care as usual.Methods
An economic evaluation was conducted alongside a cluster-randomised controlled trial with 12 months follow-up. Treatment providers were randomised to either a 2-day training in the SHARP-at work intervention, i.e. a problem solving intervention, or care as usual. Effect outcomes were the incidence of recurrent sickness absence and time to recurrent sickness absence. Self-reported health care utilisation was measured by questionnaires. A cost-effectiveness analysis (CEA) from the societal perspective and a cost-benefit analysis (CBA) from the employer’s perspective were conducted.Results
The CEA showed that the SHARP-at work intervention was more effective but also more expensive than care as usual. The CBA revealed that employer’s occupational health care costs were significantly higher in the intervention group compared to care as usual. Overall, the SHARP-at work intervention showed no economic benefit compared to care as usual.Conclusions
As implementation of the SHARP-at work intervention might require additional investments, health care policy makers need to decide if these investments are worthwhile considering the results that can be accomplished in reducing recurrent sickness absence. 相似文献84.
Klara De Cort Dirk Hermans Daphne Noortman Wiesje Arends Eric J. L. Griez Koen R. J. Schruers 《PloS one》2013,8(8)
In cognitive theory it is hypothesized that panic attacks are provoked by catastrophic misinterpretations of bodily sensations. The aim of the present study was to investigate the ability of associated word pairs referring to catastrophic thinking (e.g. palpitations-heart attack) in producing panic attacks. Patients with PD (n = 20), patients with mixed anxiety disorders (n = 20), and a healthy control group (n = 30) participated in the present study. To enhance ecological validity we first conducted a stimulus validation experiment. Subsequently, nine suitable panic and neutral word pairs were presented in block to the participants. Anxiety levels were assessed before and after the presentation. PD patients were more anxious when reading these word pairs, compared to neutral word pairs. However, none of the participants experienced a panic attack upon reading the word pairs. From the present results it seems that catastrophic thinking is rather related to the anticipatory anxiety for panic attacks, but not necessarily with the occurrence of the panic attacks themselves. 相似文献
85.
Nikolaus Goessweiner-Mohr Lukas Grumet Karsten Arends Tea Pavkov-Keller Christian C. Gruber Karl Gruber Ruth Birner-Gruenberger Andrea Kropec-Huebner Johannes Huebner Elisabeth Grohmann Walter Keller 《The Journal of biological chemistry》2013,288(3):2018-2028
Conjugative plasmid transfer is the most important means of spreading antibiotic resistance and virulence genes among bacteria and therefore presents a serious threat to human health. The process requires direct cell-cell contact made possible by a multiprotein complex that spans cellular membranes and serves as a channel for macromolecular secretion. Thus far, well studied conjugative type IV secretion systems (T4SS) are of Gram-negative (G−) origin. Although many medically relevant pathogens (e.g., enterococci, staphylococci, and streptococci) are Gram-positive (G+), their conjugation systems have received little attention. This study provides structural information for the transfer protein TraM of the G+ broad host range Enterococcus conjugative plasmid pIP501. Immunolocalization demonstrated that the protein localizes to the cell wall. We then used opsonophagocytosis as a novel tool to verify that TraM was exposed on the cell surface. In these assays, antibodies generated to TraM recruited macrophages and enabled killing of pIP501 harboring Enteroccocus faecalis cells. The crystal structure of the C-terminal, surface-exposed domain of TraM was determined to 2.5 Å resolution. The structure, molecular dynamics, and cross-linking studies indicated that a TraM trimer acts as the biological unit. Despite the absence of sequence-based similarity, TraM unexpectedly displayed a fold similar to the T4SS VirB8 proteins from Agrobacterium tumefaciens and Brucella suis (G−) and to the transfer protein TcpC from Clostridium perfringens plasmid pCW3 (G+). Based on the alignments of secondary structure elements of VirB8-like proteins from mobile genetic elements and chromosomally encoded T4SS from G+ and G− bacteria, we propose a new classification scheme of VirB8-like proteins. 相似文献
86.
87.
Marine micro-organisms have been playing highly diverse roles over evolutionary time: they have defined the chemistry of the oceans and atmosphere. During the last decades, the bioreactors with novel designs have become an important tool to study marine microbiology and ecology in terms of: marine microorganism cultivation and deep-sea bioprocess characterization; unique bio-chemical product formation and intensification; marine waste treatment and clean energy generation. In this review we briefly summarize the current status of the bioreactor technology applied in marine microbiology and the critical parameters to take into account during the reactor design. Furthermore, when we look at the growing population, as well as, the pollution in the coastal areas of the world, it is urgent to find sustainable practices that beneficially stimulate both the economy and the natural environment. Here we outlook a few possibilities where innovative bioreactor technology can be applied to enhance energy generation and food production without harming the local marine ecosystem. 相似文献
88.
89.
Fehrmann RS Jansen RC Veldink JH Westra HJ Arends D Bonder MJ Fu J Deelen P Groen HJ Smolonska A Weersma RK Hofstra RM Buurman WA Rensen S Wolfs MG Platteel M Zhernakova A Elbers CC Festen EM Trynka G Hofker MH Saris CG Ophoff RA van den Berg LH van Heel DA Wijmenga C Te Meerman GJ Franke L 《PLoS genetics》2011,7(8):e1002197
For many complex traits, genetic variants have been found associated. However, it is still mostly unclear through which downstream mechanism these variants cause these phenotypes. Knowledge of these intermediate steps is crucial to understand pathogenesis, while also providing leads for potential pharmacological intervention. Here we relied upon natural human genetic variation to identify effects of these variants on trans-gene expression (expression quantitative trait locus mapping, eQTL) in whole peripheral blood from 1,469 unrelated individuals. We looked at 1,167 published trait- or disease-associated SNPs and observed trans-eQTL effects on 113 different genes, of which we replicated 46 in monocytes of 1,490 different individuals and 18 in a smaller dataset that comprised subcutaneous adipose, visceral adipose, liver tissue, and muscle tissue. HLA single-nucleotide polymorphisms (SNPs) were 10-fold enriched for trans-eQTLs: 48% of the trans-acting SNPs map within the HLA, including ulcerative colitis susceptibility variants that affect plausible candidate genes AOAH and TRBV18 in trans. We identified 18 pairs of unlinked SNPs associated with the same phenotype and affecting expression of the same trans-gene (21 times more than expected, P<10(-16)). This was particularly pronounced for mean platelet volume (MPV): Two independent SNPs significantly affect the well-known blood coagulation genes GP9 and F13A1 but also C19orf33, SAMD14, VCL, and GNG11. Several of these SNPs have a substantially higher effect on the downstream trans-genes than on the eventual phenotypes, supporting the concept that the effects of these SNPs on expression seems to be much less multifactorial. Therefore, these trans-eQTLs could well represent some of the intermediate genes that connect genetic variants with their eventual complex phenotypic outcomes. 相似文献
90.
Gu W Wang T Maltais F Ledford B Kennedy J Wei Y Gross CH Parsons J Duncan L Arends SJ Moody C Perola E Green J Charifson PS 《Bioorganic & medicinal chemistry letters》2012,22(11):3693-3698
A series of 2,6-disubstituted aminoalkoxypyrimidine carboxamides (AAPCs) with potent inhibition of bacterial NAD(+)-dependent DNA ligase was discovered through the use of structure-guided design. Two subsites in the NAD(+)-binding pocket were explored to modulate enzyme inhibitory potency: a hydrophobic selectivity region was explored through a series of 2-alkoxy substituents while the sugar (ribose) binding region of NAD(+) was explored via 6-alkoxy substituents. 相似文献