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91.
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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Summary Although an increased plasma non-esterified fatty acid (NEFA) concentration has been shown to increase insulin resistance (Randle cycle), decrease insulin secretion and increase hepatic gluconeogenesis, the effect of NEFA on the deterioration of glucose tolerance has not been studied prospectively in Caucasian subjects. Therefore, we investigated whether plasma NEFA may be regarded as predictors of deterioration of glucose tolerance in subjects with normal (NGT, n = 3671) or impaired (IGT, n = 418) glucose tolerance who were participants in the Paris Prospective study. The subjects were first examined between 1967 and 1972 and underwent two 75-g oral glucose tolerance tests 2 years apart with measurements of plasma glucose, insulin and NEFA concentrations. Glucose tolerance deteriorated from NGT to IGT or non-insulin-dependent diabetes (NIDDM) in 177 subjects and from IGT to NIDDM in 32 subjects. In multivariate analysis, high fasting plasma NEFA in NGT subjects and high 2-h plasma NEFA and low 2-h plasma insulin concentrations in IGT subjects were significant independent predictors of deterioration along with older age, high fasting and 2-h plasma glucose concentrations and high iliac to thigh ratio. When subjects were divided by tertiles of plasma NEFA concentration at baseline, there was an increase in 2-h glucose concentration with increasing NEFA in the subjects who did not deteriorate, but no effect of plasma NEFA in those who deteriorated. In subjects with IGT who deteriorated compared with those who did not 2-h plasma insulin concentration was lower but there was no evidence that this resulted from an effect of plasma NEFA. Our data suggest that a high plasma NEFA concentration is a risk marker for deterioration of glucose tolerance independent of the insulin resistance or the insulin secretion defect that characterize subjects at risk for NIDDM. [Diabetologia (1997) 40: 1101–1106] Received: 11 March 1997 and in revised form: 20 May 1997  相似文献   
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OBJECTIVES: To investigate the predictive value of testing for antineutrophil cytoplasmic antibodies (ANCA) in 55 patients with systemic Wegener's granulomatosis (WG) included in a randomized, prospective trial comparing corticosteroids and oral or pulse cyclophosphamide. METHODS: All 55 patients received corticosteroids. A cyclophosphamide pulse of 0.7 g/m2 was given at the time of diagnosis. After the first pulse, the patients were assigned at random to receive either pulse or oral cyclophosphamide (2 mg/kg/day), independently of ANCA results. ANCA were sought using an immunofluorescence assay and an attempt was made to correlate them with relapse of WG. ANCA were monitored throughout the study. RESULTS: At the time of diagnosis, ANCA were detected in 48 (87%) patients, with a cytoplasmic labelling pattern in 44 and a perinuclear pattern in four. ANCA follow-up was available for 50 patients. ANCA disappeared in 34 patients and persisted in nine. For 79% of the patients, the clinical course improved with the disappearance of ANCA and deteriorated with their persistence or increased titre. Among the patients who were initially ANCA-positive, 23 relapses occurred. Relapses were more frequent when ANCA remained positive or reappeared [13/19 ANCA-positive patients vs 3/29 ANCA-negative patients (P<0.01)]. Nine relapses (39%) occurred in patients with persistent ANCA, and ANCA reappearance preceded relapse in eight (35%). The mean time between inclusion and relapse did not differ between the patients who became ANCA-negative and those who were persistently ANCA-positive (14.6+/-13.2 vs 14.4+/-8.2 months). The mean time to ANCA disappearance was similar for the patients who relapsed and those who did not. Corticosteroids and pulse or oral cyclophosphamide did not significantly modify the time to ANCA disappearance. Throughout the study, seven patients were ANCA-negative. CONCLUSION: Although ANCA positivity was associated with relapse, discordance between cytoplasmic ANCA and disease activity was not unusual. In the absence of clinical manifestations, ANCA titres alone can serve as a warning signal but not indicate whether to adjust or initiate treatment.  相似文献   
94.
OBJECTIVE: To determine whether following the onset of intraarticular inflammation, there is early damage to articular cartilage, specifically to types II and IX collagen, and the proteoglycan (PG) aggrecan, and whether measurement of the degradation products of these molecules in synovial fluid (SF) and serum may permit the detection of cartilage damage. METHODS: A rabbit model of rheumatoid arthritis, antigen (ovalbumin)-induced arthritis, was studied. Articular cartilage samples were analyzed by immunoassays for total type II collagen content, its denaturation and cleavage by collagenases, and for type IX collagen content. PG content was determined by colorimetric assay. In serum and SF, total PG content and collagenase-generated peptides of type II collagen were measured. RESULTS: After 6 days, both the PG content and the NC4 domain of type IX collagen were reduced in femoral and tibial cartilage, concomitant with the onset of arthritis. In only the tibial cartilage did this reduction in PG persist up to day 20. However, denatured type II collagen was increased in all cartilage samples, but only on day 20. In SF, the PG content was significantly reduced on day 20, and products of type II collagen cleavage by collagenase were significantly increased on both day 6 and day 20. CONCLUSION: This study, which is the first of its kind examining changes in both types II and IX collagen and PG content, reveals early damage to both types of collagen as well as to PG in articular cartilage samples following induction of joint inflammation. SF analyses reveal this early damage and may be of value in the study and treatment of inflammatory arthritic diseases such as rheumatoid arthritis.  相似文献   
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96.

Objectives

To provide an evidence-based overview of the effectiveness of conservative and (post)surgical interventions for trigger finger, Dupuytren disease, and De Quervain disease.

Data Sources

Cochrane Library, Physiotherapy Evidence Database, PubMed, Embase, and CINAHL were searched to identify relevant systematic reviews and randomized controlled trials (RCTs).

Data Selection

Two reviewers independently applied the inclusion criteria to select potential studies.

Data Extraction

Two reviewers independently extracted the data and assessed the methodologic quality.

Data Synthesis

A best-evidence synthesis was performed to summarize the results. Two reviews (trigger finger and De Quervain disease) and 37 randomized controlled trials (RCTs) (trigger finger: n=8; Dupuytren disease: n=14, and De Quervain disease: n=15) were included. The trials reported on oral medication (Dupuytren disease), physiotherapy (De Quervain disease), injections and surgical treatment (trigger finger, Dupuytren disease, and De Quervain disease), and other conservative (De Qervain disease) and postsurgical treatment (Dupuytren disease). Moderate evidence was found for the effect of corticosteroid injection on the very short term for trigger finger, De Quervain disease, and for injections with collagenase (30d) when looking at all joints, and no evidence was found when looking at the PIP joint for Dupuytren disease. A thumb splint as additive to a corticosteroid injection seems to be effective (moderate evidence) for De Quervain disease (short term and midterm). For Dupuytren disease, use of a corticosteroid injection within a percutaneous needle aponeurotomy in the midterm and tamoxifen versus a placebo before or after a fasciectomy seems to promising (moderate evidence). We also found moderate evidence for splinting after Dupuytren surgery in the short term.

Conclusions

In recent years, more and more RCTs have been conducted to study treatment of the aforementioned hand disorders. However, more high-quality RCTs are still needed to further stimulate evidence-based practice for patients with trigger finger, Dupuytren disease, and De Quervain disease.  相似文献   
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