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101.
Gas station workers are exposed to chemicals known to be carcinogenic, especially benzene. The objective was to analyze the health problems of female gas station workers by means of sociodemographic and clinical questionnaires, and laboratorial exams. We performed the genotyping of the polymorphisms BRCA1/P871L and BRCA1/Q356R by Polymerase Chain Reaction‐Restriction Fragment Length Polymorphism, and of variant allele BRCA2/N372H through direct sequencing. The female workers showed a higher concentration of monocytes (P = 0.039); a greater number of spontaneous abortions (P = 0.025, OR = 4.977, 95% CI = 1.135–30.669); higher tobacco consumption (P = 0.013); and higher alcohol consumption (P = 0.05). The statistical analysis of the polymorphisms associated with the variables monocyte concentration and miscarriage number did not reveal a significant relationship, and smoking and spontaneous abortion were not statistically associated either. Environ. Mol. Mutagen. 58:730–734, 2017. © 2017 Wiley Periodicals, Inc.  相似文献   
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Dense deposit disease (DDD) is a severe renal disease characterized by accumulation of electron-dense material in the mesangium and glomerular basement membrane. Previously, DDD has been associated with deficiency of factor H (fH), a plasma regulator of the alternative pathway (AP) of complement activation, and studies in animal models have linked pathogenesis to the massive complement factor 3 (C3) activation caused by this deficiency. Here, we identified a unique DDD pedigree that associates disease with a mutation in the C3 gene. Mutant C3923ΔDG, which lacks 2 amino acids, could not be cleaved to C3b by the AP C3-convertase and was therefore the predominant circulating C3 protein in the patients. However, upon activation to C3b by proteases, or to C3(H2O) by spontaneous thioester hydrolysis, C3923ΔDG generated an active AP C3-convertase that was regulated normally by decay accelerating factor (DAF) but was resistant to decay by fH. Moreover, activated C3b923ΔDG and C3(H2O)923ΔDG were resistant to proteolysis by factor I (fI) in the presence of fH, but were efficiently inactivated in the presence of membrane cofactor protein (MCP). These characteristics cause a fluid phase–restricted AP dysregulation in the patients that continuously activated and consumed C3 produced by the normal C3 allele. These findings expose structural requirements in C3 that are critical for recognition of the substrate C3 by the AP C3-convertase and for the regulatory activities of fH, DAF, and MCP, all of which have implications for therapeutic developments.  相似文献   
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The antibodies of the Dombrock blood group system have only rarely been encountered in transfusion practice, and anti-Dob has not previously been implicated in an acute hemolytic transfusion reaction. We have encountered the first such case involving a chronically transfused black female with hemoglobin SS disease and multiple antibodies in her serum. During a previous admission for sickle cell crisis, the patient received 3 units of compatible blood with no untoward effects. Serum obtained 21 days later contained, in addition to the known antibodies, anti-S plus an unidentified antibody showing characteristics of HTLA. Blood lacking the E, K1, Fy(a), Jk(b) and S antigens was obtained, and 2 least incompatible units were transfused. While administering the second unit, the patient complained of fever and low back pain, and hemoglobinemia was detected. Anti-Dob was identified in the post-reaction samples by absorption-elution tests, and the patient was confirmed to be Do(a+b–). The first unit transfused during this hemolytic episode tested Do (b+). This case, and a similar case involving anti-Doa reported in 1986, strengthens the belief that Dombrock antibodies are clinically significant and illustrates the need for their differentiation, prior to transfusion from less clinically significant HTLA antibodies.  相似文献   
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The Coronary Artery Revascularization Prophylaxis (CARP) study showed no survival benefit with preoperative coronary artery revascularization before elective vascular surgery. The generalizability of the trial results to all patients with multivessel coronary artery disease (CAD) has been questioned. The objective of this study was to determine the impact of prophylactic coronary revascularization on long-term survival in patients with multivessel CAD. Over a 4-year period, 1,048 patients underwent coronary angiography before vascular surgery during screening into the CARP trial. The cohort was composed of registry (n = 586) and randomized (n = 462) patients, and their survival was determined at 2.5 years after vascular surgery. High-risk coronary anatomy without previous bypass surgery included 2-vessel disease (n = 204 [19.5%]), 3-vessel disease (n = 130 [12.4%]), and left main coronary artery stenosis >/=50% (n = 48 [4.6%]). By log-rank test, preoperative revascularization was associated with improved survival in patients with a left main coronary artery stenoses (0.84 vs 0.52, p <0.01) but not those with either 2-vessel (0.80 vs 0.79, p = 0.83) or 3-vessel (0.79 vs 0.71, p = 0.15) disease. In conclusion, unprotected left main coronary artery disease was present in 4.6% of patients who underwent coronary angiography before vascular surgery, and this was the only subset of patients showing a benefit with preoperative coronary artery revascularization.  相似文献   
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OBJECTIVES: The aim of our study was to evaluate the safety and midterm clinical results of dexamethasone-eluting stent (DexES) implantation in ST-segment elevation acute myocardial infarction (STEMI). BACKGROUND: Inflammation plays a pivotal role in both inestabilization of coronary atherosclerotic plaques and development of restenosis after stent placement. Antiinflammatory agents may attenuate those mechanisms and improve clinical outcomes. There is little information about clinical results of DexES and no data are available about their utilization during percutaneous coronary intervention (PCI) in STEMI. METHODS: Consecutive patients with STEMI that underwent primary or rescue PCI in our institution were treated with DexES. Clinical follow-up with routine realization of noninvasive test for detection of myocardial ischemia and coronariography if necessary, were performed. The objective of the study was to evaluate the rate of MACE (death, reinfarction, or target lesion revascularization) during midterm follow-up. RESULTS: The procedure was successful in 96.7% of cases. There were no in-hospital deaths or reinfarctions. One acute stent thrombosis occurred and no subacute thrombosis were observed. During a mean follow-up period of 384 days, cardiac-related death was 1.1%, there were no reinfarctions or late stent thrombosis and target lesion revascularization rate was 4.2%. CONCLUSION: We conclude that utilization of DexES for PCI in STEMI is safe and provides good midterm clinical outcomes.  相似文献   
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Purpose

Bifascicular block and prolonged PR interval on the electrocardiogram (ECG) have been associated with complete heart block and sudden cardiac death. We sought to determine if cardiac implantable electronic devices (CIED) improve survival in these patients.

Methods

We assessed survival in relation to CIED status among 636 consecutive patients with bifascicular block and prolonged PR interval on the ECG. In survival analyses, CIED was considered as a time-varying covariate.

Results

Average age was 76?±?9 years, and 99% of the patients were men. A total of 167 (26%) underwent CIED (127 pacemaker only) implantation at baseline (n?=?23) or during follow-up (n?=?144). During 5.4?±?3.8 years of follow-up, 83 (13%) patients developed complete or high-degree atrioventricular block and 375 (59%) died. Patients with a CIED had a longer survival compared to those without a CIED in the traditional, static analysis (log-rank p?<?0.0001) but not when CIED was considered as a time-varying covariate (log-rank p?=?0.76). In the multivariable model, patients with a CIED had a 34% lower risk of death (hazard ratio 0.66, 95% confidence interval 0.52–0.83; p?=?0.001) than those without CIED in the traditional analysis but not in the time-varying covariate analysis (hazard ratio 1.05, 95% confidence interval 0.79–1.38; p?=?0.76). Results did not change in the subgroup with a pacemaker only.

Conclusions

Bifascicular block and prolonged PR interval on ECG are associated with a high incidence of complete atrioventricular block and mortality. However, CIED implantation does not have a significant influence on survival when time-varying nature of CIED implantation is considered.
  相似文献   
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