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Background and objective: Cytotoxic T-lymphocyte antigen 4 (CTLA-4) signalling of regulatory T cells regulates mucosal lymphocyte tolerance and differentiation, and may therefore have a beneficial effect in allergic diseases such as asthma. The aim of this study was to evaluate the effects of fluticasone propionate (FP) on CD4+CD25+ T cell co-expression of CTLA-4 in the sputum of mild asthmatic subjects. Methods: Eleven mild, stable asthmatic subjects completed a double-blind, randomized, cross-over, placebo-controlled study to compare the effects of 14 days 200 µg twice daily FP and placebo. Before and after treatment, airway hyperresponsiveness was measured, and sputum was induced for measurements of CTLA-4+CD4+CD25+ cells, eosinophils and levels of IL-10, IL-13 and transforming growth factor (TGF)-β Results: FP treatment increased co-expression of CTLA-4 on sputum CD4+CD25+ cells from a mean (SEM) of 7.9% (1.8) to 12.7% (3.3) after 14 days treatment (P < 0.05) compared with placebo. FP treatment also significantly increased IL-10 levels, reduced per cent sputum eosinophils, and reduced airway hyperresponsiveness (P < 0.05). There was a significant negative correlation between the change in airway hyperresponsiveness and per cent sputum eosinophils (P < 0.01), but no correlation with changes in CTLA-4+CD4+CD25+ cells (P > 0.05). There was no change in the levels of sputum IL-13 or TGF-β Conclusions: The percentage of airway CTLA-4+CD4+CD25+ cells increased after FP treatment, coincident with improvements in airway inflammation and hyperresponsiveness. Whether improved asthma assessments are related to the increase in CTLA-4+CD4+CD25+ cells and thus improved regulation of T-cell tolerance and differentiation will require a larger sample size to determine. The normalization of CTLA-4+CD4+CD25+ cells in asthma may contribute to the management of this disease.  相似文献   
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Outbreaks of methicillin-resistant Staphylococcus aureus (MRSA) in the neonatal intensive care unit (NICU) have been reported worldwide. Some outbreaks were caused by USA300, which is a community-associated MRSA clone. In 2011, polymerase chain reaction-based open reading frame typing (POT) for the initial MRSA isolates from all inpatients was started at the Tokyo Metropolitan Children's Medical Center. From March 2014 to April 2015, a total of 131 MRSA strains were isolated, 104 of which were analyzed as healthcare-associated MRSA. Thirteen stains (12.5%) had a POT number of 106-9-93, which strongly suggested USA300; these included 6 from nasal swabs, 6 from blood cultures and 1 from subcutaneous pus. All the MRSA strains were isolated from patients in the NICU; were typed as sequence type 8, spa type t008, and staphylococcal cassette chromosome type mec IVa; and possessed the lukS-lukF and arginine catabolic mobile element-arcA gene. Pulsed-field gel electrophoresis of all the strains, with USA300-0114 as a reference, showed indistinguishable banding pattern. Based on these results, POT was useful in recognizing this first MRSA outbreak of USA300 in a Japanese NICU and was advantageous in terms of swiftness, less cost and monitoring change of the epidemic MRSA lineage.  相似文献   
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Background

Central obesity has been proved to be a strong risk factor for numerous health-related problems as well as mortality. However, there have been no studies on the relationship between central obesity and locomotive syndrome (LS). The present study investigated the influence of central obesity on LS.

Methods

A total of 217 females between the ages of 60 and 79 years (mean 68.2 ± 5.0 years) who completed the questionnaires, physical examination and physical performance tests in the Yakumo study in 2011–2012 were enrolled in this study. Participants were assessed according to the 25-Question Geriatric Locomotive Function Scale (GLFS-25), visual analog scale (VAS) for lower back pain (LBP) and knee pain, and the Roland Morris Disability Questionnaire (RDQ). LS was defined as having a score of >16 points on the GLFS-25. Height, weight, waist circumference (WC), hip circumference, % body fat and bone mineral density were measured. Body mass index and waist-to-hip ratio were calculated. The timed up-and-go test, one-leg standing time with eyes open, 10-m gait time and maximum stride were assessed. Back muscle strength and grip strength were measured. The relationships between obesity-related parameters and GLFS-25, RDQ, VAS and physical performance tests were analyzed.

Results

The GLFS-25, LBP and knee pain showed significant correlation with most of obesity-related parameters. Among obesity-related parameters, WC was most strongly related to the GLFS-25, LBP and knee pain. When participants were stratified by WC, larger WC was significantly associated with a higher GLFS-25 score, higher prevalence of LS and higher VAS for LBP and knee pain as well as poorer results in some physical performance tests even after adjustment by age.

Conclusions

The present study revealed that central obesity is significantly associated with LS, and WC can be a useful parameter to assess the risk of LS in elderly women.  相似文献   
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Ionizing radiation induces DNA double-strand breaks (DSBs). Mammalian cells repair DSBs through multiple pathways, and the repair pathway that is utilized may affect cellular radiation sensitivity. In this study, we examined effects on cellular radiosensitivity resulting from functional alterations in homologous recombination (HR). HR was inhibited by overexpression of the forkhead-associated (FHA) domain-mutated NBS1 (G27D/R28D: FHA-2D) protein in HeLa cells or in hamster cells carrying a human X-chromosome. Cells expressing FHA-2D presented partially (but significantly) HR-deficient phenotypes, which were assayed by the reduction of gene conversion frequencies measured with a reporter assay, a decrease in radiation-induced Mre11 foci formation, and hypersensitivity to camptothecin treatments. Interestingly, ectopic expression of FHA-2D did not increase the frequency of radiation-induced somatic mutations at the HPRT locus, suggesting that a partial reduction of HR efficiency has only a slight effect on genomic stability. The expression of FHA-2D rendered the exponentially growing cell population slightly (but significantly) more sensitive to ionizing radiation. This radiosensitization effect due to the expression of FHA-2D was enhanced when the cells were irradiated with split doses delivered at 24-h intervals. Furthermore, enhancement of radiation sensitivity by split dose irradiation was not seen in contact-inhibited G0/G1 populations, even though the cells expressed FHA-2D. These results suggest that the FHA domain of NBS1 might be an effective molecular target that can be used to induce radiosensitization using low molecular weight chemicals, and that partial inhibition of HR might improve the effectiveness of cancer radiotherapy.  相似文献   
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PurposeCD157 (also known as Bst1) positive vascular endothelial stem cells (VESCs), which contribute to vascular regeneration, have been recently identified in mouse organs, including the retinas, brain, liver, lungs, heart, and skin. However, VESCs have not been identified in the choroid. The purpose of this study was to identify VESCs in choroidal vessels and to establish the protocol to isolate retinal and choroidal VESCs.MethodsWe established an efficient protocol to create single-cell suspensions from freshly isolated mouse retina and choroid by enzymatic digestion using dispase, collagenase, and type II collagenase. CD157-positive VESCs, defined as CD31+CD45CD157+ cells, were sorted using fluorescence-activated cell sorting (FACS).ResultsIn mouse retina, among CD31+CD45 endothelial cells (ECs), 1.6 ± 0.2% were CD157-positive VESCs, based on FACS analysis. In mouse choroid, among CD31+CD45 ECs, 4.5 ± 0.4% were VESCs. The CD157-positive VESCs generated a higher number of EC networks compared with CD157-negative non-VESCs under vascular endothelial growth factor (VEGF) in vitro cultures. The EC network area, defined as the ratio of the CD31-positive area to the total area in each field, was 4.21 ± 0.39% (retinal VESCs) and 0.27 ± 0.12% (retinal non-VESCs), respectively (P < 0.01). The EC network area was 8.59 ± 0.78% (choroidal VESCs) and 0.14 ± 0.04% (choroidal non-VESCs), respectively (P < 0.01). The VESCs were located in large blood vessels but not in the capillaries.ConclusionsWe confirmed distinct populations of CD157-positive VESCs in both mouse retina and choroid. VESCs are located in large vessels and have the proliferative potential. The current results may open new avenues for the research and treatment of ocular vascular diseases.  相似文献   
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A phase I study of a biweekly outpatient regimen composed of carboplatin (CBDCA) and paclitaxel (TXL) was conducted for advanced non-small cell lung cancer. TXL was given in combination with a fixed dose of CBDCA (AUC 3) every 2 weeks. The starting dose of TXL was 100 mg/m2, and the dose was escalated in increments of 20 mg/m2. Three to six patients were allocated to each level. Toxicities were evaluated in the first 4 courses to determine the maximum tolerated dose (MTD). TXL 160 mg/m2 dosages proved to be MTD, and the dose limiting toxicity (DLT) was hematotoxicity (neutropenia). The patients, however, recovered from neutropenia using G-CSF immediately, when G-CSF was used. Gastrointestinal toxicity was well-tolerated. A response was found in 9 out of 20 patients who received 4 courses or more (45%). These results suggest that the recommended dose would be CBDCA (AUC 3) + TXL 140 mg/m2. The biweekly regimen has a high level clinical activity and excellent tolerability, and is suitable for outpatients. We started a phase II study because of these results.  相似文献   
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Secondary pulmonary alveolar proteinosis (PAP) is one of the complications of hematologic malignancy and immunosuppressive diseases. We encountered four cases of myelodysplastic syndrome (MDS) associated with PAP detected on autopsy. They consisted of two refractory anemia (RA) and two patients with refractory anemia with excess blasts in transformation (RAEBt) at the time of MDS diagnosis, but all of them developed leukemic phase and were resistant to chemotherapy at the time of pulmonary episodes. Of the four MDS patients, two also had pulmonary aspergillosis. Previously, 69 patients with PAP associated with hematologic disorders have been reported, but there have been only seven cases with MDS, including our four patients. Of the 69 reported cases of PAP in hematologic malignancies, 24/63 (38%) informative patients with infection had fungal infections of the lung; 2/7 (29%) MDS cases had fungal infection. We should, therefore, pay careful attention to this possibility in cases of MDS with lung complications, including PAP, especially in patients in the leukemic phase of MDS.  相似文献   
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