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91.
Clostridium difficile causes antibiotic-associated diarrhea and pseudomembraneous colitis and is responsible for a large and increasing fraction of hospital-acquired infections. Fecal microbiota transplantation (FMT) is an alternate treatment option for recurrent C. difficile infection (RCDI) refractory to antibiotic therapy. It has recently been discussed favorably in the clinical and scientific communities and is receiving increasing public attention. However, short- and long-term health consequences of FMT remain a concern, as the effects of the transplanted microbiota on the patient remain unknown. To shed light on microbial events associated with RCDI and treatment by FMT, we performed fecal microbiota analysis by 16S rRNA gene amplicon pyrosequencing of 14 pairs of healthy donors and RCDI patients treated successfully by FMT. Post-FMT patient and healthy donor samples collected up to one year after FMT were studied longitudinally, including one post-FMT patient with antibiotic-associated relapse three months after FMT. This analysis allowed us not only to confirm prior reports that RCDI is associated with reduced diversity and compositional changes in the fecal microbiota, but also to characterize previously undocumented post-FMT microbiota dynamics. Members of the Streptococcaceae, Enterococcaceae, or Enterobacteriaceae were significantly increased and putative butyrate producers, such as Lachnospiraceae and Ruminococcaceae were significantly reduced in samples from RCDI patients before FMT as compared to post-FMT patient and healthy donor samples. RCDI patient samples showed more case-specific variations than post-FMT patient and healthy donor samples. However, none of the bacterial groups were invariably associated with RCDI or successful treatment by FMT. Overall microbiota compositions in post-FMT patients, specifically abundances of the above-mentioned Firmicutes, continued to change for at least 16 weeks after FMT, suggesting that full microbiota recovery from RCDI may take much longer than expected based on the disappearance of diarrheal symptoms immediately after FMT.  相似文献   
92.
93.

Background

Secreted Protein Acidic and Rich in Cysteine (SPARC) is expressed during tissue repair and regulates cellular proliferation, migration and cytokine expression. The aim was to determine if SPARC modifies intestinal inflammation.

Methods

Wild-type (WT) and SPARC-null (KO) mice received 3% dextran sodium sulphate (DSS) for 7 days. Inflammation was assessed endoscopically, clinically and histologically. IL-1β, IL-4, IL-5, IL-6, IL-10, IL-13, IL-17A, IL-12/IL23p40, TNF-α, IFN-γ, RANTES, MCP-1, MIP-1α, MIP-1β, MIG and TGF-β1 levels were measured by ELISA and cytometric bead array. Inflammatory cells were characterised by CD68, Ly6G, F4/80 and CD11b immunofluorescence staining and regulatory T cells from spleen and mesenteric lymph nodes were assessed by flow cytometry.

Results

KO mice had less weight loss and diarrhoea with less endoscopic and histological inflammation than WT animals. By day 35, all (n = 13) KO animals completely resolved the inflammation compared to 7 of 14 WT mice (p<0.01). Compared to WTs, KO animals at day 7 had less IL1β (p = 0.025) and MIG (p = 0.031) with higher TGFβ1 (p = 0.017) expression and a greater percentage of FoxP3+ regulatory T cells in the spleen and draining lymph nodes of KO animals (p<0.01). KO mice also had fewer CD68+ and F4/80+ macrophages, Ly6G+ neutrophils and CD11b+ cells infiltrating the inflamed colon.

Conclusions

Compared to WT, SPARC KO mice had less inflammation with fewer inflammatory cells and more regulatory T cells. Together, with increased TGF-β1 levels, this could aid in the more rapid resolution of inflammation and restoration of the intestinal mucosa suggesting that the presence of SPARC increases intestinal inflammation.  相似文献   
94.

Objectives

To (1) identify social and rehabilitation predictors of nursing home placement, (2) investigate the association between effectiveness and efficiency in rehabilitation and nursing home placement of patients admitted for inpatient rehabilitation from 1996 to 2005 by disease in Singapore.

Design

National data were retrospectively extracted from medical records of community hospital.

Data Sources

There were 12,506 first admissions for rehabilitation in four community hospitals. Of which, 8,594 (90.3%) patients were discharged home and 924 (9.7%) patients were discharged to a nursing home. Other discharge destinations such as sheltered home (n = 37), other community hospital (n = 31), death in community hospital (n = 12), acute hospital (n = 1,182) and discharge against doctor’s advice (n = 24) were excluded.

Outcome Measure

Nursing home placement.

Results

Those who were discharged to nursing home had 33% lower median rehabilitation effectiveness and 29% lower median rehabilitation efficiency compared to those who were discharged to nursing homes. Patients discharged to nursing homes were significantly older (mean age: 77 vs. 73 years), had lower mean Bathel Index scores (40 vs. 48), a longer median length of stay (40 vs. 33 days) and a longer time to rehabilitation (19 vs. 15 days), had a higher proportion without a caregiver (28 vs. 7%), being single (21 vs. 7%) and had dementia (23 vs. 10%). Patients admitted for lower limb amputation or falls had an increased odds of being discharged to a nursing home by 175% (p<0.001) and 65% (p = 0.043) respectively compared to stroke patients.

Conclusions

In our study, the odds of nursing home placement was found to be increased in Chinese, males, single or widowed or separated/divorced, patients in high subsidy wards for hospital care, patients with dementia, without caregivers, lower functional scores at admission, lower rehabilitation effectiveness or efficiency at discharge and primary diagnosis groups such as fractures, lower limb amputation and falls in comparison to strokes.  相似文献   
95.
Caspase-6 is an effector caspase that has not been investigated thoroughly despite the fact that Caspase-6 is strongly activated in Alzheimer disease brains. To understand the full physiological impact of Caspase-6 in humans, we investigated Caspase-6 expression. We performed western blot analyses to detect the pro-Caspase-6 and its active p20 subunit in fetal and adult lung, kidney, brain, spleen, muscle, stomach, colon, heart, liver, skin, and adrenals tissues. The levels were semi-quantitated by densitometry. The results show a ubiquitous expression of Caspase-6 in most fetal tissues with the lowest levels in the brain and the highest levels in the gastrointestinal system. Caspase-6 active p20 subunits were only detected in fetal stomach. Immunohistochemical analysis of a human fetal embryo showed active Caspase-6 positive apoptotic cells in the dorsal root ganglion, liver, lung, kidney, ovary, skeletal muscle and the intestine. In the adult tissues, the levels of Caspase-6 were lower than in fetal tissues but remained high in the colon, stomach, lung, kidney and liver. Immunohistological analyses revealed that active Caspase-6 was abundant in goblet cells and epithelial cells sloughing off the intestinal lining of the adult colon. These results suggest that Caspase-6 is likely important in most tissues during early development but is less involved in adult tissues. The low levels of Caspase-6 in fetal and adult brain indicate that increased expression as observed in Alzheimer Disease is a pathological condition. Lastly, the high levels of Caspase-6 in the gastrointestinal system indicate a potential specific function of Caspase-6 in these tissues.  相似文献   
96.

Purpose

The objective of our study was to examine horizontal smooth pursuit performance in strabismic children and in children with vergence deficits, and to compare these data with those recorded in a group of control age-matched children.

Methods

Binocular eye movements were recorded by video-oculography in ten strabismic children (mean age: 9.8±0.8) and seven children with vergence deficits (mean age: 10.8±0.6). Data were compared to that of age-matched control children (mean age: 9.8±0.8 years).

Results

Catch-up saccades amplitude in strabismic children and in children with vergence deficits were significantly higher than in control age-matched children. Moreover, in strabismic children the amplitude of catch-up saccades was significantly higher in rightward than in leftward direction. The number of catch-up saccades was also significantly higher in rightward than in leftward direction. The gain value of pursuits in rightward direction was significantly higher in the right eye than in the left one; for the right eye, the gain value was significantly higher in rightward than in leftward direction. Binocular coordination of pursuit was better in control age-matched children than in children with vergence deficits and than in strabismic children.

Conclusions

Binocular coordination of pursuit is abnormal in children with vergence deficits and worse in strabismic children. Binocular vision plays an important role in improving binocular coordination of pursuit.  相似文献   
97.
Recombinases of the RecA family play vital roles in homologous recombination, a high-fidelity mechanism to repair DNA double-stranded breaks. These proteins catalyze strand invasion and exchange after forming dynamic nucleoprotein filaments on ssDNA. Increasing evidence suggests that stabilization of these dynamic filaments is a highly conserved function across diverse species. Here, we analyze the presynaptic filament formation and DNA binding characteristics of the Sulfolobus solfataricus recombinase SsoRadA in conjunction with the SsoRadA paralog SsoRal1. In addition to constraining SsoRadA ssDNA-dependent ATPase activity, the paralog also enhances SsoRadA ssDNA binding, effectively influencing activities necessary for presynaptic filament formation. These activities result in enhanced SsoRadA-mediated strand invasion in the presence of SsoRal1 and suggest a filament stabilization function for the SsoRal1 protein.  相似文献   
98.
For a hectare of oil palm plantation, about 21.63 tonnes of biomass comprising 20.43 % empty fruit bunches, 5.09 % palm kernel shells, 11.65 % oil palm trunks, 50.30 % oil palm fronds and 12.53 % palm pressed fibre is produced per year as wastes which keep raising many environmental concerns as most of them are incinerated and dumped at open sites. Oil palm wastes are found to contain phytochemicals which have anti-cancer, antioxidants and other vital biological activities. About 17–65 kg of carotenoids, 0.1–60 kg phenolic compounds, 0.6–39 kg sterols and 4.0–62 kg tocols could be extracted from these wastes which would not only boost the economy but also help improve human health and promote clean environments. This study assesses the phytochemistry of oil palm wastes and their pharmacological activities beneficial to the nutraceutical industry with the view of utilizing oil palm wastes for sustainable development.  相似文献   
99.

Background

Limited knowledge on the prevalence and distribution of risk factors impairs the planning and implementation of cardiovascular prevention programs in the Latin American and Caribbean (LAC) region.

Methods and Findings

Prevalence of hypertension, diabetes mellitus, abnormal lipoprotein levels, obesity, and smoking were estimated from individual-level patient data pooled from population-based surveys (1998–2007, n = 31,009) from eight LAC countries and from a national survey of the United States (US) population (1999–2004) Age and gender specific prevalence were estimated and age-gender adjusted comparisons between both populations were conducted. Prevalence of diabetes mellitus, hypertension, and low high-density lipoprotein (HDL)-cholesterol in LAC were 5% (95% confidence interval [95% CI]: 3.4, 7.9), 20.2% (95% CI: 12.5, 31), and 53.3% (95% CI: 47, 63.4), respectively. Compared to LAC region’s average, the prevalence of each risk factor tended to be lower in Peru and higher in Chile. LAC women had higher prevalence of obesity and low HDL-cholesterol than men. Obesity, hypercholesterolemia, and hypertriglyceridemia were more prevalent in the US population than in LAC population (31 vs. 16.1%, 16.8 vs. 8.9%, and 36.2 vs. 26.5%, respectively). However, the prevalence of low HDL-cholesterol was higher in LAC than in the US (53.3 vs. 33.7%).

Conclusions

Major cardiovascular risk factors are highly prevalent in LAC region, in particular low HDL-cholesterol. In addition, marked differences do exist in this prevalence profile between LAC and the US. The observed patterns of obesity-related risk factors and their current and future impact on the burden of cardiovascular diseases remain to be explained.  相似文献   
100.

Background

The role of relative humidity in the aerosol transmission of influenza was examined in a simulated examination room containing coughing and breathing manikins.

Methods

Nebulized influenza was coughed into the examination room and Bioaerosol samplers collected size-fractionated aerosols (<1 µM, 1–4 µM, and >4 µM aerodynamic diameters) adjacent to the breathing manikin’s mouth and also at other locations within the room. At constant temperature, the RH was varied from 7–73% and infectivity was assessed by the viral plaque assay.

Results

Total virus collected for 60 minutes retained 70.6–77.3% infectivity at relative humidity ≤23% but only 14.6–22.2% at relative humidity ≥43%. Analysis of the individual aerosol fractions showed a similar loss in infectivity among the fractions. Time interval analysis showed that most of the loss in infectivity within each aerosol fraction occurred 0–15 minutes after coughing. Thereafter, losses in infectivity continued up to 5 hours after coughing, however, the rate of decline at 45% relative humidity was not statistically different than that at 20% regardless of the aerosol fraction analyzed.

Conclusion

At low relative humidity, influenza retains maximal infectivity and inactivation of the virus at higher relative humidity occurs rapidly after coughing. Although virus carried on aerosol particles <4 µM have the potential for remaining suspended in air currents longer and traveling further distances than those on larger particles, their rapid inactivation at high humidity tempers this concern. Maintaining indoor relative humidity >40% will significantly reduce the infectivity of aerosolized virus.  相似文献   
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