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91.
BrkA confers resistance to killing by complement in Bordetella pertussis. Complement resistance in Bordetella bronchiseptica was examined. Four B. bronchiseptica strains possessed the brkA gene; however, only three expressed the protein. Only the strain lacking BrkA was susceptible to complement. Introduction of the B. pertussis brkA gene restored BrkA expression to this strain but did not confer resistance. brkA was mutated in the strains that naturally expressed BrkA, and loss of BrkA did not confer sensitivity to complement. As a species, B. bronchiseptica is more resistant to complement than B. pertussis, and BrkA does not mediate resistance.  相似文献   
92.
Apoptosis and inflammation play an important role in the pathogenesis of direct/pulmonary acute lung injury (ALI). However, the role of the Fas receptor-driven apoptotic pathway in indirect/nonpulmonary ALI is virtually unstudied. We hypothesized that if Fas or caspase-8 plays a role in the induction of indirect ALI, their local silencing using small interfering RNA (siRNA) should be protective in hemorrhage-induced septic ALI. Initially, as a proof of principle, green fluorescent protein-siRNA was administered intratracheally into transgenic mice overexpressing green fluorescent protein. Twenty-four hours after siRNA delivery, lung sections revealed a significant decrease in green fluorescence. Intratracheally administered Cy-5-labeled Fas-siRNA localized primarily in pulmonary epithelial cells. Intratracheal instillation of siRNA did not induce lung inflammation via toll-like receptor or protein kinase PKR pathways as assessed by lung tissue interferon-alpha, tumor necrosis factor-alpha, and interleukin (IL)-6 levels. Mice subjected to hemorrhagic shock and sepsis received either Fas-, caspase-8-, or control-siRNA intratracheally 4 hours after hemorrhage. Fas- or caspase-8-siRNA significantly reduced lung tissue Fas or caspase-8 mRNA, respectively. Only Fas-siRNA markedly diminished lung tissue tumor necrosis factor-alpha, IL-6, IL-10, interferon-gamma, IL-12, and caspase-3 activity. Fas-siRNA also preserved alveolar architecture and reduced lung neutrophil infiltration and pulmonary epithelial apoptosis. These data indicate the pathophysiological significance of Fas activation in nonpulmonary/shock-induced ALI and the feasibility of intrapulmonary administration of anti-apoptotic siRNA in vivo.  相似文献   
93.
BACKGROUND: To reduce outpatient waiting times, a growing number of outpatient clinics for selected groups of patients are being provided by GPs with special interests (GPwSIs). AIM: To determine whether there are differences in patient satisfaction or clinical outcome among patients attending orthopaedic clinics provided by GPwSIs in hospital or community settings. DESIGN OF STUDY: Randomised controlled trial. SETTING: Hospital outpatient departments or general practices. METHOD: Three hundred and twenty-one patients with minor orthopaedic problems were referred by GPs to the orthopaedic surgery department of the University Hospitals of Leicester NHS Trust; 168 patients were randomised to care by GPwSIs in practices, and 153 were randomised to care by the same GPwSIs in clinics held at hospital outpatient departments. Patients completed the SF-36v2 and satisfaction questionnaires at their first appointment, and again 3 months later. RESULTS: There was no significant difference between the sites in changes in health. After the first clinic attendance, patients attending practice-based clinics were more satisfied with access to appointments and information received. CONCLUSION: For selected orthopaedic referrals seen by GPwSIs, there were no significant differences in clinical outcomes between practice-based and hospital-based clinics, but some features of practice-based clinics tend to be preferred by patients.  相似文献   
94.
OBJECTIVE: As a result of the HIV epidemic in Africa, much debate exists on whether institutionalized compared with community-based care provides optimum management of infected children. Previous reports calculated 89% mortality by age 3 years among outpatients in Malawi. No similar data are available for infected children in institutionalized care. We characterized patterns of morbidity and mortality among HIV-1-infected children residing at an orphanage in Nairobi. METHODS: Medical records for 174 children followed over 5 years were reviewed. Mortality was analyzed by Kaplan-Meier methods with adjustment to account for survival in the community before admission. Anthropometric indices were calculated to include mean z scores for weight for length and length for age. Low indices reflected wasting and stunting. Opportunistic infections were documented. RESULTS: Of 174 children, 64 had died. Survival was 70% at age 3 years. Morbidity included recurrent respiratory tract infections, gastroenteritis, parotitis, and lymphoid interstitial pneumonitis. No new cases of tuberculosis disease were noted after admission. Mean z scores for length for age suggested overall stunting (z = -1.65). Wasting was not observed (z = -0.39). CONCLUSION: The optimal form of care for HIV-infected children in resource-poor settings may be the development of similar homes. Absence of tuberculosis disease in long-standing residents may have contributed to improved survival. Stunting in the absence of wasting implied that growth was compromised by opportunistic infections and other cofactors.  相似文献   
95.
Saccharomyces cerevisiae ATS1 (-tubulin suppressor 1) was originally identified as a high-copy suppressor of class two -tubulin mutations and was proposed to have a regulatory role in coordinating the microtubule state with the cell cycle. Here, we show that Ats1p interacts with Nap1p, a cytoplasmic protein that regulates the activity of the Cdc28p/Clb2p complex. Loss of Nap1p results in a delayed switch from polar to isotropic bud growth. The delayed switch results in elongated buds. Nap1p and Ats1p interact in two-hybrid and co-immunoprecipitation assays. Both nap1 and ats1 cells have a Clb2p-dependent elongated bud morphology. Deletion of ATS1 partially suppresses the elongated bud morphology and benomyl resistance of nap1 mutants. Our results suggest Ats1p might regulate coordination of the microtubule state with the cell cycle through an interaction with Nap1p.Communicated by S. Hohmann  相似文献   
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Different polymorphisms have been described in the minimal promoter region (MPR) of the interferon-gamma receptor 1 (IFNGR1), a molecule that plays a critical role in mycobacterial control. We sequenced the IFNGR1 MPR from African American, Caucasian and Korean controls, and from mycobacteria-infected patients. Six different single nucleotide polymorphisms (SNPs) were detected in the IFNGR1 MPR. The three ethnic groups showed different SNP distribution patterns, but no significant differences were detected between mycobacterial cases and controls. Two polymorphisms were found in all populations (G-611A, T-56C). We cloned the four allelic variants (var) of haplotype G-611A/T-56C into a luciferase reporter vector and determined their promoter activity. Polymorphisms at position -611 had a stronger effect on the promoter activity than those at position -56, and constructs carrying G-611 produced a stronger promoter activity than -611A constructs. The IFNGR1 MPR is a polymorphic region with at least two SNPs influencing its activity, but these are not associated with increased mycobacterial susceptibility.  相似文献   
100.
ContextExercise-related lower leg pain (ERLLP) is common in runners.ObjectiveTo compare biomechanical (kinematic, kinetic, and spatiotemporal) measures obtained from wearable sensors as well as lower extremity alignment, range of motion, and strength during running between runners with and those without ERLLP.DesignCase-control study.SettingField and laboratory.Patients or Other ParticipantsOf 32 young adults who had been running regularly (>10 mi [16 km] per week) for ≥3 months, 16 had ERLLP for ≥2 weeks and 16 were healthy control participants.Main Outcome Measure(s)Both field and laboratory measures were collected at the initial visit. The laboratory measures consisted of alignment (arch height index, foot posture index, navicular drop, tibial torsion, Q-angle, and hip anteversion), range of motion (great toe, ankle, knee, and hip), and strength. Participants then completed a 1.67-mi (2.69-km) run along a predetermined route to calibrate the RunScribe devices. The RunScribe wearable sensors collected kinematic (pronation excursion and maximum pronation velocity), kinetic (impact g and braking g), and spatiotemporal (stride length, step length, contact time, stride pace, and flight ratio) measures. Participants then wore the sensors during at least 3 training runs in the next week.ResultsThe ERLLP group had a slower stride pace than the healthy group, which was accounted for as a covariate in subsequent analyses. The ERLLP group had a longer contact time during the stance phase of running (mean difference [MD] = 18.00 ± 8.27 milliseconds) and decreased stride length (MD = −0.11 ± 0.05 m) than the control group. For the clinical measures, the ERLLP group demonstrated increased range of motion for great-toe flexion (MD = 13.9 ± 4.6°) and ankle eversion (MD = 6.3 ± 2.7°) and decreased strength for ankle inversion (MD = −0.49 ± 0.23 N/kg), ankle eversion (MD = −0.57 ± 0.27 N/kg), and hip flexion (MD = −0.99 ± 0.39 N/kg).ConclusionsThe ERLLP group exhibited a longer contact time and decreased stride length during running as well as strength deficits at the ankle and hip. Gait retraining and lower extremity strengthening may be warranted as clinical interventions in runners with ERLLP.  相似文献   
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