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991.
Marcelle Bens Sophie Vimont Sanae Ben Mkaddem Cécilia Chassin Jean‐Michel Goujon Viviane Balloy Michel Chignard Catherine Werts Alain Vandewalle 《Cellular microbiology》2014,16(10):1503-1517
Uropathogenic Escherichia coli (UPEC) colonizing kidneys is the main cause of acute pyelonephritis. TLR5 that senses flagellin was shown to be highly expressed in the bladder and to participate in host defence against flagellated UPEC, although its role in kidneys still remains elusive. Here we show that TLR5 is expressed in renal medullary collecting duct (MCD) cells, which represent a preferential site of UPEC adhesion. Flagellin, like lipopolysaccharide, stimulated the production of the chemoattractant chemokines CXCL1 and CXCL2, and subsequent migration capacity of neutrophils in cultured wild‐type (WT) and Tlr4?/? MCDs, but not in Tlr5?/? MCDs. UPEC can translocate across intact MCD layers without altering tight junctions. Strikingly, the invasion capacity and transcellular translocation of the UPEC strain HT7 were significantly lower in Tlr5?/? than in WT MCDs. The non‐motile HT7ΔfliC mutant lacking flagellin also exhibited much lower translocation capacities than the HT7 isolates. Finally, Tlr5?/? kidneys exhibited less infiltrating neutrophils than WT kidneys one day after the transurethral inoculation of HT7, and greater delayed renal bacterial loads in the day 4 post‐infected Tlr5?/? kidneys. Overall, these findings indicate that the epithelial TLR5 participates to renal antibacterial defence, but paradoxically favours the translocation of UPEC across intact MCD cell layers. 相似文献
992.
Josquin Daron Natasha Glover Lise Pingault Sébastien Theil Véronique Jamilloux Etienne Paux Valérie Barbe Sophie Mangenot Adriana Alberti Patrick Wincker Hadi Quesneville Catherine Feuillet Frédéric Choulet 《Genome biology》2014,15(12)
Background
The 17 Gb bread wheat genome has massively expanded through the proliferation of transposable elements (TEs) and two recent rounds of polyploidization. The assembly of a 774 Mb reference sequence of wheat chromosome 3B provided us with the opportunity to explore the impact of TEs on the complex wheat genome structure and evolution at a resolution and scale not reached so far.Results
We develop an automated workflow, CLARI-TE, for TE modeling in complex genomes. We delineate precisely 56,488 intact and 196,391 fragmented TEs along the 3B pseudomolecule, accounting for 85% of the sequence, and reconstruct 30,199 nested insertions. TEs have been mostly silent for the last one million years, and the 3B chromosome has been shaped by a succession of bursts that occurred between 1 to 3 million years ago. Accelerated TE elimination in the high-recombination distal regions is a driving force towards chromosome partitioning. CACTAs overrepresented in the high-recombination distal regions are significantly associated with recently duplicated genes. In addition, we identify 140 CACTA-mediated gene capture events with 17 genes potentially created by exon shuffling and show that 19 captured genes are transcribed and under selection pressure, suggesting the important role of CACTAs in the recent wheat adaptation.Conclusion
Accurate TE modeling uncovers the dynamics of TEs in a highly complex and polyploid genome. It provides novel insights into chromosome partitioning and highlights the role of CACTA transposons in the high level of gene duplication in wheat.Electronic supplementary material
The online version of this article (doi:10.1186/s13059-014-0546-4) contains supplementary material, which is available to authorized users. 相似文献993.
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995.
Julien Paccou Cédric Boudot Cédric Renard Sophie Liabeuf Said Kamel Patrice Fardellone Ziad Massy Michel Brazier Romuald Mentaverri 《Arthritis research & therapy》2014,16(5):1-9
Introduction
Human circulating monocytes express the calcium-sensing receptor (CaSR) and are involved in atherosclerosis. This study investigated the potential association between vascular calcification in rheumatoid arthritis (RA) and CaSR expression in circulating monocytes.Methods
In this cross-sectional study, 50 RA patients were compared to 25 control subjects matched for age and gender. Isolation of peripheral blood mononuclear cells and flow cytometry analysis were performed to study the surface and total CaSR expression in circulating monocytes. Coronary artery calcium (CAC) and abdominal aortic calcification (AAC) scores were evaluated by computed tomography and an association between these scores and the surface and/or total CaSR expression in circulating monocytes in RA patients was investigated.Results
The two groups were similar in terms of age (RA: 60.9 ± 8.3 years, versus controls: 59.6 ± 5.3 years) and gender (RA: 74.0% females versus 72.0% females). We did not find a higher prevalence and greater burden of CAC or AAC in RA patients versus age- and gender-matched controls. When compared with control subjects, RA patients did not exhibit greater total CaSR (101.6% ± 28.8 vs. 99.9% ± 22.0) or surface CaSR (104.6% ± 20.4 vs. 99.9% ± 13.7) expression, but total CaSR expression in circulating monocytes was significantly higher in RA patients with severe CAC (Agatston score ≥200, n = 11) than in patients with mild-to-moderate CAC (1 to 199, n = 21) (P = 0.01).Conclusions
This study demonstrates for the first time that total CaSR expression in human circulating monocytes is increased in RA patients with severe coronary artery calcification. 相似文献996.
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998.
Pascal Geldsetzer Thomas Christie Williams Amir Kirolos Sarah Mitchell Louise Alison Ratcliffe Maya Kate Kohli-Lynch Esther Jill Laura Bischoff Sophie Cameron Harry Campbell 《PloS one》2014,9(4)
Background
Pneumonia, diarrhoea, and malaria are among the leading causes of death in children. These deaths are largely preventable if appropriate care is sought early. This review aimed to determine the percentage of caregivers in low- and middle-income countries (LMICs) with a child less than 5 years who were able to recognise illness in their child and subsequently sought care from different types of healthcare providers.Methods and Findings
We conducted a systematic literature review of studies that reported recognition of, and/or care seeking for episodes of diarrhoea, pneumonia or malaria in LMICs. The review is registered with PROSPERO (registration number: CRD42011001654). Ninety-one studies met the inclusion criteria. Eighteen studies reported data on caregiver recognition of disease and seventy-seven studies on care seeking. The median sensitivity of recognition of diarrhoea, malaria and pneumonia was low (36.0%, 37.4%, and 45.8%, respectively). A median of 73.0% of caregivers sought care outside the home. Care seeking from community health workers (median: 5.4% for diarrhoea, 4.2% for pneumonia, and 1.3% for malaria) and the use of oral rehydration therapy (median: 34%) was low.Conclusions
Given the importance of this topic to child survival programmes there are few published studies. Recognition of diarrhoea, malaria and pneumonia by caregivers is generally poor and represents a key factor to address in attempts to improve health care utilisation. In addition, considering that oral rehydration therapy has been widely recommended for over forty years, its use remains disappointingly low. Similarly, the reported levels of care seeking from community health workers in the included studies are low even though global action plans to address these illnesses promote community case management. Giving greater priority to research on care seeking could provide crucial evidence to inform child mortality programmes. 相似文献999.
The negative implications of living in a socially unequal society are now well documented. However, there is poor understanding of the pathways from specific environmental risk to symptoms. Here we examine the associations between social deprivation, depression, and psychotic symptoms using the 2007 Adult Psychiatric Morbidity Survey, a cross-sectional dataset including 7,353 individuals. In addition we looked at the mediating role of stress, discrimination, trust and lack of social support. We found that the participants'' neighbourhood index of multiple deprivation (IMD) significantly predicted psychosis and depression. On inspection of specific psychotic symptoms, IMD predicted paranoia, but not hallucinations or hypomania. Stress and trust partially mediated the relationship between IMD and paranoid ideation. Stress, trust and a lack of social support fully mediated the relationship between IMD and depression. Future research should focus on the role deprivation and social inequalities plays in specific manifestations of psychopathology and investigate mechanisms to explain those associations that occur. Targeting the mediating mechanisms through appropriate psychological intervention may go some way to dampen the negative consequences of living in an unjust society; ameliorating economic injustice may improve population mental health. 相似文献
1000.
The pathogens Campylobacter jejuni and Campylobacter coli are commensals in the poultry intestine and campylobacteriosis is one of the most frequent foodborne diseases in developed and developing countries. Phages were identified to be effective in reducing intestinal Campylobacter load and this was evaluated, in the first field trials which were recently carried out. The aim of this study was to further investigate Campylobacter population dynamics during phage application on a commercial broiler farm. This study determines the superiority in colonisation of a Campylobacter type found in a field trial that was susceptible to phages in in vitro tests. The colonisation factors, i.e. motility and gamma glutamyl transferase activity, were increased in this type. The clustering in phylogenetic comparisons of MALDI-TOF spectra did not match the ST, biochemical phenotype and phage susceptibility. Occurrence of Campylobacter jejuni strains and phage susceptibility types with different colonisation potential seem to play a very important role in the success of phage therapy in commercial broiler houses. Thus, mechanisms of both, phage susceptibility and Campylobacter colonisation should be further investigated and considered when composing phage cocktails. 相似文献