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131.
BACKGROUND & AIMS: Collagenous colitis (CC) is a well-described entity causing chronic diarrhea and characteristic histologic findings. Several treatment options have been suggested, but no controlled data are available. We conducted a placebo-controlled trial to show the clinical and histologic effects of budesonide in CC. METHODS: Twenty-eight patients were randomly assigned to receive placebo (n = 14) or budesonide 9 mg daily (n = 14) for 8 weeks. Patients were evaluated clinically, and blinded biopsy specimens were analyzed from fixed locations at weeks 0 and 8. Clinical response was defined as a decrease of at least 50% in the disease activity score (number of bowel movements in the last 7 days). At week 8, nonresponders received open-label budesonide for the next 8-week period; responders discontinued treatment and were followed up. RESULTS: Three patients discontinued the study prematurely. Intention-to-treat analysis showed clinical response in 8 of 14 patients in the budesonide group compared with 3 of 14 responders for placebo (P = 0.05) after 8 weeks of blinded therapy, together with improved stool consistency. Histologically, there was no change in the mean thickness of the collagen band but a significant decrease of the lamina propria infiltrate in the budesonide group (P < 0.001). CONCLUSIONS: Budesonide is efficacious in inducing short-term clinical response in CC with significant reduction of the histologic infiltrate in the lamina propria.  相似文献   
132.
To understand why once-weekly isoniazid/rifapentine therapy for tuberculosis was less effective than twice-weekly isoniazid/rifampin, we studied human immunodeficiency virus-seronegative patients with either failure (n = 4), relapse (n = 35), or cure (n = 94), recruited from a comparative treatment trial. In multivariate analyses that were adjusted for severity of disease, low plasma concentrations of isoniazid were associated with failure/relapse with once-weekly isoniazid/rifapentine (median isoniazid area under the concentration-time curve for 12 hours after the dose [AUC(0-12)] was 36 microg x hour/ml in failure/relapse versus 56 microg x hour/ml in control cases p = 0.005), but not with twice-weekly isoniazid/rifampin. Furthermore, two patients who relapsed with Mycobacterium tuberculosis monoresistant to rifamycin had very low concentrations of isoniazid. Finally, isoniazid acetylator status determined by N-acetyltransferase type 2 genotype was associated with outcome with once-weekly isoniazid/rifapentine (p = 0.03) but not twice-weekly isoniazid/rifampin. No rifamycin pharmacokinetic parameter was consistently and significantly associated with outcome (p > 0.10). Because low isoniazid concentrations were associated with failure/relapse, a drug with consistently greater area under the concentration-time curve than isoniazid may be needed to achieve highly active once-weekly therapy with rifapentine.  相似文献   
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Analysis of the spatiotemporal coupling between neuronal activity and cerebral blood flow requires the precise measurement of the dynamics of RBC flow in individual capillaries that irrigate activated neurons. Here, we use two-photon microscopy in vivo to image individual RBCs in glomerular capillaries in the rat dorsal olfactory bulb. We find that odor stimulation evokes capillary vascular responses that are odorant- and glomerulus-specific. These responses consist of increases as well as decreases in RBC flow, both resulting from independent changes in RBC velocity or linear density. Finally, measuring RBC flow with micrometer spatial resolution and millisecond temporal resolution, we demonstrate that, in olfactory bulb superficial layers, capillary vascular responses precisely outline regions of synaptic activation.  相似文献   
136.

Background

To estimate patient acceptable symptom state (PASS) and minimal clinically important difference (MCID) for patient-reported outcomes in systemic sclerosis (SSc).

Methods

We conducted a secondary analysis of the SCLEREDUC trial, a 12-month randomized controlled trial comparing the efficacy of physical therapy to usual care in 220 SSc patients followed-up from September 2005 to October 2010. Self-rated state and change in patient health at 12 months were assessed by using 2 external anchors extracted from the Medical Outcomes Study 36-Item Short-Form. Patients who self-rated their health as “excellent”, “very good” or “good” were the PASS group and those who self-rated their health change as “somewhat better” were the MCID group. Main outcomes were the estimates of PASS by using the 75th percentile method and of MCID by using the mean change in scores method for pain and activity limitation.

Results

PASS (95% confidence interval) and mean (SD) MCID estimates at 12 months were 53.75 (34.00 to 68.00) and ?6.74 (32.02) for the joint-pain visual analog scale (range 0–100), 1.41 (1.13 to 1.63) and ?0.21 (0.48) for the Health Assessment Questionnaire (HAQ, range 0–3), 1.27 (1.07 to 1.62) and ?0.13 (0.45) for the scleroderma HAQ (range 0–3), 26.00 (17.00 to 37.00) and -3.38 (9.87) for the Cochin Hand Function Scale (range 0–90), and 19.40 (17.20 to 21.90) and ?5.69 (6.79) for the McMaster-Toronto Arthritis Patient Preference Disability Questionnaire (range 0–30), respectively.

Conclusions

We provide, for the first time, the PASS and MCID estimates for pain and activity limitation in SSc.

Trial registration

ClinicalTrials.gov Identifier: NCT00318188. First Posted: April 26, 2006.  相似文献   
137.
OBJECTIVES: This study aimed to compare changes in coronary endothelial function, systemic endothelin-1 (ET-1) levels, and vascular remodeling in heart transplant recipients randomized to cyclosporin A (CyA) or tacrolimus (Tac) immunosuppression. BACKGROUND: Functional endothelial abnormalities and intimal thickening are sensitive measures of early cardiac allograft vasculopathy (CAV). METHODS: The randomized, prospective study was performed in two groups of 22 patients, maintained on Tac or CyA and mycophenolate mofetil immunosuppression, 1 and 12 months after heart transplantation. We investigated epicardial luminal diameter, coronary blood flow velocity, and ET-1 plasma levels at 1 and 12 months after transplantation. Structural coronary alterations were determined using intravascular ultrasound. RESULTS: Epicardial vasomotor function at baseline and during follow-up was comparable between the groups. Deterioration of microvascular endothelial function during follow-up was significantly enhanced in the CyA versus Tac group (p < 0.05). Circulating ET-1 concentration increased in the CyA group but significantly decreased over time in the Tac group (CyA +17% vs. Tac -25%; p < 0.05). The time-dependent increase in mean intimal area was significantly enhanced in the CyA versus Tac group, whereas the vessel area significantly increased during follow-up in the Tac compared with the CyA group. CONCLUSIONS: Epicardial endothelial function is comparable between CyA- and Tac-treated patients. Microvascular endothelial function deteriorates more in CyA-treated patients, a finding that correlates with enhanced ET-1 concentration and an increased intimal area during follow-up. The mean vessel area in the Tac group increased over time, indicating positive vascular remodeling. Tac is superior to CyA with respect to microvascular endothelial function, intimal thickening, and vascular remodeling.  相似文献   
138.
In a cross-sectional study in 1998 we assessed human immunodeficiency virus (HIV) and syphilis infections and their risk factors among the 316 registered female sex workers (FSWs) of Toliary, south-west Madagascar. No case of HIV infection was detected, but 18.4% of registered FSWs had syphilis. Only half of these women regularly used condoms. In a multiple logistic regression analysis, risk factors for syphilis infection were multiple clients per week and, paradoxically, regular use of condoms. The variables associated with irregular use of condoms were younger ages of registered FSWs, multiple clients per week and Malagasy clients. The high prevalence of syphilis infection associated with irregular use of condoms might facilitate a very fast spread of HIV infection among these FSWs. Promotion of condom use and surveillance of sexually transmitted infections and HIV infection incidence are needed in the south of Madagascar.  相似文献   
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Production of interleukin-18 in human tuberculosis   总被引:20,自引:0,他引:20  
To investigate the role of interleukin (IL)-18 in human tuberculosis, IL-18 production was evaluated in blood and at the site of disease in patients with tuberculosis. Mycobacterium tuberculosis-stimulated peripheral blood mononuclear cells (PBMC) from tuberculosis patients secreted less IL-18 and interferon-gamma (IFN-gamma) than did PBMC from healthy persons reactive to tuberculin. M. tuberculosis-induced IFN-gamma production was inhibited by anti-IL-18 and enhanced by recombinant IL-18. Alveolar macrophages secreted IL-18 in response to M. tuberculosis, and IL-18 and IFN-gamma concentrations were higher in pleural fluid of patients with tuberculosis than in pleural fluid of patients with nontuberculous diseases. These findings demonstrate that IL-18 production by PBMC correlates with IFN-gamma production and effective immunity to tuberculosis, suggesting that IL-18 contributes to a protective type 1 cytokine response in persons with mycobacterial infection.  相似文献   
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