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The aim of this study was to compare the prosthetic joint infection (PJI) rate after total joint arthroplasty in two consecutive periods of treatment with different antibiotic prophylaxes: cefuroxime versus cefuroxime plus teicoplanin. We retrospectively reviewed 1,896 patients who underwent total hip arthroplasty or total knee arthroplasty between March 2010 and February 2013. From March 2010 to August 2011, patients received 1.5 g of cefuroxime during induction of anesthesia and another 1.5 g 2 h later (the C group). From September 2011, 800 mg of teicoplanin was added to cefuroxime (the CT group). Throughout the period studied, there were no variations in pre- or postoperative protocols. Univariate and multivariate analyses were performed to evaluate independent predictors of PJI. There were 995 (55.7%) patients in the C group and 791 (44.3%) in the CT group. Patients in the CT group had a significantly lower PJI rate than patients in the C group (1.26% versus 3.51%, P = 0.002). There were no infections due to Staphylococcus aureus in the CT group (0% versus 1.6% in the C group, P < 0.001). A stepwise forward Cox regression model identified male sex (hazard ratio [HR], 3.85; 95% confidence interval [CI], 2.09 to 7.18), a body mass index of ≥35 kg/m2 (HR, 2.93; 95% CI, 1.37 to 6.27), the presence of lung disease (HR, 2.46; 95% CI, 1.17 to 5.15), and red blood cell transfusion (HR, 3.70; 95% CI, 1.89 to 7.23) to be independent variables associated with a higher risk of PJI. The addition of teicoplanin was associated with a lower risk of infection (HR, 0.35; 95% CI, 0.17 to 0.74). In conclusion, the addition of teicoplanin to cefuroxime during primary arthroplasty was associated with a significant reduction in the global PJI rate due to a reduction of infections caused by Gram-positive bacteria.  相似文献   
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OBJECTIVES: At present, many clinical trials of anti-HIV-1 therapies compare treatments by a primary endpoint that measures the durability of suppression of HIV-1 replication. Several durability endpoints are compared. DESIGN: Endpoints are compared by their implicit assumptions regarding surrogacy for clinical outcomes, sample size requirements, and accommodations for inter-patient differences in baseline plasma HIV-1-RNA levels and in initial treatment response. METHODS: Virological failure is defined by the non-suppression of virus levels at a prespecified follow-up time T(early virological failure), or by relapse. A binary virological failure endpoint is compared with three time-to-virological failure endpoints: time from (i) randomization that assigns early failures a failure time of T weeks; (ii) randomization that extends the early failure time T for slowly responding subjects; and (iii) virological response that assigns non-responders a failure time of 0 weeks. Endpoint differences are illustrated with Agouron's trial 511. RESULTS: In comparing high with low-dose nelfinavir (NFV) regimens in Agouron 511, the difference in Kaplan-Meier estimates of the proportion not failing by 24 weeks is 16.7% (P = 0.048), 6.5% (P = 0.29) and 22.9% (P = 0.0030) for endpoints (i), (ii) and (iii), respectively. The results differ because NFV suppresses virus more quickly at the higher dose, and the endpoints weigh this treatment difference differently. This illustrates that careful consideration needs to be given to choosing a primary endpoint that will detect treatment differences of interest. CONCLUSION: A time from randomization endpoint is usually recommended because of its advantages in flexibility and sample size, especially at interim analyses, and for its interpretation for patient management.  相似文献   
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Aims/hypothesis Knowledge of the factors which simultaneously contribute to insulin-resistance-related inflammation may contribute to early therapeutic targeting. IL-18 has recently been described as one of the factors which, in addition to insulin resistance, may also contribute to atherosclerosis. However, the source of IL-18 is not well characterised.Materials and methods We aimed to study body composition (bioelectric impedance), glucose tolerance (OGTT) and insulin sensitivity (minimal model method) in relation to serum IL-18 (ELISA) concentration in 144 otherwise healthy men aged 51.9±12.5 years.Results In contrast to previous observations in women, circulating IL-18 was not significantly associated with BMI (r=0.12, p=0.1) or WHR (r=0.08, p=0.3). IL-18 was also not associated with absolute or percent fat mass (bioelectric impedance, p>0.20) but, interestingly, it was significantly linked to fat-free mass (p=0.03). Serum IL-18 increased with each quartile of fat-free mass, corresponding to values of 64.2; >64.2 to 71.6; >71.6 to 80.9; and 80.9 kg (ANOVA, p<0.0001). IL-18 was more closely associated with postload glucose during an OGTT (p=0.04) rather than with fasting glucose (p=0.1). HbA1c (p=0.03), HDL-cholesterol (p=0.04) and serum triglycerides (p=0.03) and parameters of systemic inflammation (C-reactive protein, p=0.02) were also significantly associated with circulating IL-18. Insulin sensitivity (minimal model analysis) was linked to circulating IL-18 (p=0.01). In a multiple linear regression analysis this relationship remained significant after controlling for BMI, age and glucose tolerance status. In another model, both fat-free mass and insulin sensitivity contributed to 10% of IL-18 variance.Conclusions/interpretation Fat mass does not seem to influence circulating IL-18, as initially proposed. In contrast, the fat-free mass compartment (a well-known confounder in the evaluation of insulin sensitivity) may significantly contribute to the relationship between IL-18 and insulin action.  相似文献   
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