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Mediastinitis is a rare but serious postoperative complication of cardiac surgery that increases mortality rates, hospital length of stay, and medical costs. A clinical trial was conducted to investigate whether the type of postoperative surgical dressing (silver nylon or standard gauze) affects the rate of mediastinal infections. The sample consisted of 1,600 surgical cardiac patients. Infection rates in the standard gauze group (control, n = 1,235) were collected retrospectively from 24 months of infection control records. In the prospective treatment arm of the study, the wounds of all consecutive surgical patients (n = 365) were covered with a silver nylon dressing and patients were assessed during the 3-week postoperative visit. Thirteen (13) patients in the control group (1%) and none of the patients in the treatment group developed mediastinitis (chi2 [1, N = 1,600] = 3.88, P <0.05). Study findings support the need for a large, prospective, controlled clinical study to confirm the effects of these dressings on mediastinitis, resultant morbidity, and costs of care.  相似文献   
84.
The production of immunoglobulin E (IgE) is tightly regulated. This is evidenced by the fact that it comprises less than 0.0001% of serum Ig, and aberrant production causes atopic conditions, including allergy, rhinitis, and anaphylaxis. Interleukin-4 (IL-4) is a well-characterized inducer of IgE by human and murine B cells, whereas interferon-gamma can antagonize this effect. IL-21 has also been recognized for its ability to suppress IL-4-induced IgE production by murine B cells. Here, we identified IL-21 as an inducer of IgE production by CD40L-stimulated human naive B cells. Furthermore, there was a striking synergy between IL-4 and IL-21 on inducing IgE secretion by CD40L-stimulated human B cells, such that the levels detected under these conditions exceeded those induced by IL-4 or IL-21 alone by more than 10-fold. IL-21 induced activation of STAT3 and analysis of B cells from patients with loss-of-function STAT3 mutations revealed that the ability of IL-21 to induce IgE secretion, and augment that driven by IL-4, was STAT3-dependent. These findings highlight a fundamental difference between the regulation of IgE production by human and murine B cells and have implications for the dysregulated production of IgE in conditions characterized by extremely high levels of serum IgE.  相似文献   
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The efficacy of fenofibrate (FEN), rosiglitazone (RSG), or a calorie-restricted diet (CRD) to reduce cardiovascular disease risk was compared in 37 overweight/obese insulin-resistant nondiabetic subjects. Insulin sensitivity, fasting lipids and lipoproteins, and postprandial plasma glucose, insulin, free fatty acid, and triglycerides were measured before and after 3 months of treatment with FEN, RSG, or CRD. Weight decreased in the CRD group, but did not change significantly after treatment with either drug. Insulin sensitivity improved significantly in the CRD- and RSG-treated groups, but to a greater extent in those administered RSG, without a significant difference comparing FEN treatment with the CRD. Total cholesterol was significantly lower after FEN and CRD treatment. Fasting plasma triglycerides decreased significantly in the FEN- and CRD-treated groups, but postprandial concentrations decreased in only FEN-treated subjects. Significant decreases in postprandial glucose and insulin were seen in only the RSG- and CRD-treated groups. FEN administration improved dyslipidemia in these subjects without changing insulin sensitivity, whereas insulin sensitivity was enhanced in RSG-treated patients without improvement in dyslipidemia. Weight loss in the CRD group led to improvements in both insulin sensitivity and dyslipidemia, but the change in the former was less than in RSG-treated patients, and improvement in lipid metabolism not as great as with FEN. In conclusion, there did not appear to be 1 therapeutic intervention that effectively treated all metabolic abnormalities present in these patients at greatly increased risk of cardiovascular disease.  相似文献   
87.
In patients with hemophilia, the development of high-responding inhibitors to factor VIII prevents adequate replacement therapy and results in increased risk of serious bleeding episodes, poor control of joint bleeding, and progressive, debilitating joint disease. Immune tolerance therapy can eradicate inhibitors, but it is not uniformly successful. Emerging data suggest that prophylaxis using activated prothrombin complex concentrates may be effective and safe in reducing the incidence of joint bleeding during immune tolerance therapy and for patients in whom immune tolerance induction fails. However, only controlled clinical trials will ultimately demonstrate whether prophylaxis can prevent joint bleeding and damage, and improve quality of life in patients with inhibitors.  相似文献   
88.
Early complications may hamper efforts to hasten discharge after primary percutaneous coronary intervention (PCI) for myocardial infarction (MI). Glycoprotein IIb/IIIa inhibitors, by reducing early recurrent ischemia, may aid in these efforts. We examined whether adjunctive abciximab could accelerate discharge and reduce costs within a trial of primary PCI after acute MI. The CADILLAC trial randomized 2,082 patients with MI to 1 of 4 reperfusion strategies in a 2 x 2 factorial design: angioplasty, angioplasty with abciximab, stent implantation, or stenting with abciximab. Patients randomized to abciximab had postprocedural heparin withheld, and discharge scheduled for days 1.5 to 2 (low-risk patients) or days 2 to 3 (high-risk patients) after MI if they were stable. Other patients were discharged at the physician's discretion. Abciximab treatment was associated with significant reductions in the primary end points of in-hospital death, reinfarction, ischemic target vessel revascularization (TVR), or disabling stroke (5.6% vs 2.7%, p = 0.003)--largely reflecting reduced ischemic TVR (3.8% vs 1.4%, p = 0.002)--and in early subacute thrombosis (1.3% vs 0.2%, p = 0.01). Hospitalization was significantly shorter in abciximab-treated patients (median 3.1 vs 3.5 days, p <0.001), but total in-hospital costs did not differ significantly (13,413 +/- 5,309 US dollars vs 13,000 +/- 6,006 US dollars, p = 0.13). Rates of the composite end point did not differ significantly during the week after discharge (0.8% vs 0.2%, p = 0.10), nor did component event rates. Abciximab during primary PCI is associated with fewer early adverse outcomes, likely contributing to offset its cost. Hospitalizations after primary PCI are so short, however, that efforts to accelerate discharge with abciximab appear unfeasible, and overall costs remain unchanged.  相似文献   
89.

Background

Age is a strong independent predictor of outcomes after primary percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI). Whether lower rates of reperfusion success contribute to the poor prognosis in elderly patients is unknown.

Methods

A formal ST-segment analysis substudy was performed in 695 patients undergoing primary PCI for AMI in the Controlled Abciximab and Device Investigation to Lower Late Angioplasty Complications (CADILLAC) trial. Reperfusion success (determined by the magnitude of ST-segment elevation resolution [STR] after PCI) was evaluated in 4 age groups: <50 years (n = 163), ≥50 to <60 years (n = 187), ≥60 to <70 years (n = 194), and ≥70 years (n = 151).

Results

There were no differences in the age groups for angiographic procedural success >91% in all, P = .6), postprocedural Thrombolysis in Myocardial Infarction grade 3 flow >94%, P = .8), and the proportions of patients with complete, partial, or absent STR (P >.8). However, rates of 30-day mortality (0.6%, 1.1%, 3.6%, 6.0%, respectively) and major adverse cardiac events (MACE; 2.5%, 4.8%, 6.2% 9.3%, respectively) increased with age. Rates of mortality and MACE were also inversely related to the magnitude of STR. Absent STR (hazard ratio, 3.00; 95% CI, 1.37-6.58; P = .006) and age (hazard ratio, 1.34; 95% CI, 1.01-1.77; P = .04) were independent predictors of 30-day MACE by using multivariable modeling.

Conclusions

Lack of effective myocardial reperfusion is not a contributory mechanism responsible for the high morbidity and mortality rates observed in elderly patients. Nevertheless, advanced age and absent STR are both independent predictors of adverse outcomes after primary PCI, emphasizing the importance of successful reperfusion in the elderly population.  相似文献   
90.
An observational study was conducted to examine the use of sun protective hats, clothing, and sunglasses of people attending an outdoor entertainment event in an area of high‐to‐extreme ultraviolet radiation in New South Wales, Australia. Armidale is unique, as it is a highly‐elevated area, almost 1000 m above sea level, and temperatures are often mild with very high‐to‐extreme levels of ultraviolet radiation. Four trained data collectors observed attendees as they entered the event, and recorded their use of sun protective hats, clothing, and sunglasses. While more than half of the attendees wore sun protective hats, only 14% wore sun protective clothing. Broad‐brimmed hats were considered sun protective, while sun protective clothing was defined by shirts with at least three‐quarter‐length sleeves. Females were more likely to wear both a sun protective hat and clothing than males, and children were less protected than adults. Legislative changes are required to ensure that organizers of outdoor events have a legal responsibility to provide a safe environment for attendees, including strategies to help reduce ultraviolet radiation exposure.  相似文献   
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