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Chronic lead exposure has been associated with elevated blood pressure in epidemiological studies. It is not known whether the previously observed relation between blood lead and hypertension persists after significant reductions have been made in environmental lead contamination. We examined the relation between blood lead levels and blood pressure in a representative sample of 14 952 whites and blacks aged 18 years or older who participated in the Third National Health and Nutrition Examination Survey. Blood lead was measured by atomic absorption spectrophotometry and blood pressure by standard sphygmomanometry. Mean blood lead levels were significantly higher for black men and women (5.4 and 3.4 microg/dL, respectively) compared with white men and women (4.4 and 3.0 microg/dL, respectively). After multivariate adjustment for important covariables, each standard deviation higher blood lead (3.3 microg/dL) was associated with a 0.82 (95% confidence interval [CI], 0.19 to 1.44) mm Hg and a 1.55 (95% CI, 0.47 to 2.64) mm Hg higher systolic blood pressure among black men and women, respectively. In contrast, blood lead level was not associated with blood pressure among white men or women. The multivariate-adjusted odds ratio (95% CI) of hypertension associated with a 1-SD higher level of blood lead was 1.08 (95% CI, 0.99 to 1.19) for black men and 1.39 (95% CI, 1.21 to 1.61) for black women. These findings suggest that increased levels of blood lead remain an important environmental risk factor for elevated blood pressure in blacks. 相似文献
73.
Steinberg JS Arshad A Kowalski M Kukar A Suma V Vloka M Ehlert F Herweg B Donnelly J Philip J Reed G Rozanski A 《Journal of the American College of Cardiology》2004,44(6):1261-1264
OBJECTIVES: This study was designed to evaluate whether the destruction of the World Trade Center (WTC) on September 11, 2001 (9/11), led to an increased frequency of ventricular arrhythmias among patients fitted with an implantable cardioverter-defibrillator (ICD). BACKGROUND: The WTC attack induced psychological distress. Because ICDs store all serious arrhythmias for months, the attack provided a unique opportunity to compare pre- and post-9/11 frequencies of potentially lethal arrhythmias among ICD patients. METHODS: Two hundred consecutive ICD patients who presented for regularly scheduled follow-up to six affiliated clinics were recruited into this observational study. The electrograms stored in the ICDs for the three months before 9/11 and 13 months thereafter were scrutinized in a blinded manner (relative to date) for all ventricular tachyarrhythmias (tachycardia or fibrillation) triggering ICD therapy. RESULTS: The frequency of tachyarrhythmias increased significantly for the 30 days post-9/11 (p = 0.004) relative to all other months between May 2001 and October 2002. In the 30 days post-9/11, 16 patients (8%) demonstrated tachyarrhythmias, compared with only seven (3.5%) in the preceding 30 days, representing a 2.3-fold increase in risk (95% confidence interval 1.1 to 4.9; p = 0.03). The first arrhythmic event did not occur for three days following 9/11, with events accumulating in a progressive non-clustered pattern. CONCLUSIONS: Ventricular arrhythmias increased by more than twofold among ICD patients following the WTC attack. The delay in onset and the non-clustered pattern of these events differ sharply from effects following other disasters, suggesting that subacute stress may have served to promote this arrhythmogenesis. 相似文献
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Palanisamy Venkatachalam Dharm Prakash Dwivedi Vishnukanth Govindraj 《The Indian journal of tuberculosis》2021,68(2):230-235
Background and objectiveChronic Obstructive Pulmonary Disease (COPD) causes substantial morbidity and mortality across the globe. Diagnosis of COPD requires post-bronchodilator FEV1/FVC <0.70 as per GOLD Guidelines. FVC maneuver requires a minimum of 6 seconds of forceful expiration with no flow for 1 second for an accepted effort, which lacks any fixed cut-off point. This leads to discomfort, especially in advanced COPD and old aged population. We conducted this study to find the utility of FEV1/FEV6 as a surrogate for FEV1/FVC, the correlation between the two ratios, and the fixed cut-off value of FEV1/FEV6 for COPD diagnosis.MethodsThis was a prospective, cross-sectional study approved by the institutional ethics committee conducted from January 2017 to November 2018. Consented patients above 18 years suspected of COPD underwent Spirometry as per ATS guidelines. FEV1, FEV6, FEV1/FEV6 and FEV1/FVC ratios were recorded from the best acceptable maneuver.ResultsOut of 560 screened patients, 122 diagnosed as COPD. The correlation coefficient between the post-bronchodilator FEV1/FVC ratio and FEV1/FEV6 ratio was 0.972 (p < 0.01). The relationship between the post-bronchodilator FEV1/FVC ratio and FEV1/FEV6 ratio (linear regression analysis) was found out as: FEV1/FVC = ?1.845 + 1.009(FEV1/FEV6). Using this formula, the post-bronchodilator FEV1/FEV6 value of 71.845 was obtained corresponding to the post-bronchodilator FEV1/FVC value of 70.00.ConclusionWe found a positive correlation coefficient (r = 0.972, p < 0.001) between the FEV1/FEV6 and FEV1/FVC ratios and the cut off value of 71.845 (p < 0.01) for the post-bronchodilator FEV1/FEV6 ratio for the diagnosis of COPD. Thus FEV1/FEV6 should be used as a surrogate for FEV1/FVC for the diagnosis of COPD. 相似文献
77.
Sahoo PK Satapathy AK Michael E Ravindran B 《The American journal of tropical medicine and hygiene》2005,73(5):877-880
Subjects in an disease-endemic area in Orissa, India concomitantly infected with filariasis and intestinal helminths had significantly lower intensity of filarial infection in comparison with those who were infected only with filariasis. Administration of albendazole resulted in a significant decrease in the prevalence of filarial antigenemia in subjects concomitantly infected with intestinal helminths, but produced little change in this infection measure in subjects infected only with Wuchereria bancrofti. These results indicate that intestinal helminths could play a role in the anti-filarial activity of albendazole, most probably by depressing filarial infection intensity in co-infected individuals. Confirmation of these findings in a larger cohort may yield important new insights regarding the role of using albendazole in the ongoing intervention programs for the control of lymphatic filariasis. 相似文献
78.
Sahana K.S. Prakash R.M. Saldanha Supriya Kushwah Anitha S. Prabhu 《The Indian journal of tuberculosis》2018,65(3):195-199
Introduction
In spite of having BCG vaccination and tuberculosis control program for the last 50 years, prevalence of tuberculosis continues to be high in India. Inadequate diagnostic methods, suboptimal treatment and monitoring, and the lack of vigilant reporting system are some of the contributing factors for the failure of TB control.Objectives
To know the current practices among local pediatricians regarding management of TB.Materials and methods
Field based cross sectional study. All the registered pediatricians who were practicing in Mangalore, (list – local IAP branch) were included in the study. A structured Questionnaire on signs and symptoms of TB, diagnosis, strategies adopted in treatment, MDR tuberculosis and reporting of cases to RNTCP was asked. Management practice standards according to the Updated National Guidelines for Pediatric Tuberculosis in India, 2012, RNTCP guidelines in consensus with IAP, latest at the time of the study.Results
50 pediatricians participated in the study with 62% having an attachment to the teaching institution. More than 50% identified all the symptoms of TB. 64% were sending chest X-ray, Mantoux test and gastric lavage/induced sputum examination for AFB to diagnose TB. 22% were not stressing for AFB examination. Still 16% told serological tests as one of the diagnostic modality. 52% were not aware about the diagnosis of latent TB. In 16% of their cases ATT was on a trial basis. Only 52% of the clinicians are adhering to updated national (RNTCP) guidelines. 30% felt still there are drawbacks in the current RNTCP guidelines. 72% knew the correct definition of MDR tuberculosis. But only 36% of them knew the diagnostic method (gene expert/CB NAAT) of confirming the MDR TB.Conclusion
Management practices are found to be still suboptimum. Better engagement of the private sector is urgently required to improve TB management practices and to prevent diagnostic delay and drug resistance. 相似文献79.
Zhuang Z Johnson RE Haracska L Prakash L Prakash S Benkovic SJ 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(14):5361-5366
To ensure efficient and timely replication of genomic DNA, organisms in all three kingdoms of life possess specialized translesion DNA synthesis (TLS) polymerases (Pols) that tolerate various types of DNA lesions. It has been proposed that an exchange between the replicative DNA Pol and the TLS Pol at the site of DNA damage enables lesion bypass to occur. However, to date the molecular mechanism underlying this process is not fully understood. In this study, we demonstrated in a reconstituted system that the exchange of Saccharomyces cerevisiae Poldelta with Poleta requires both the stalling of the holoenzyme and the monoubiquitination of proliferating cell nuclear antigen (PCNA). A moving Poldelta holoenzyme is refractory to the incoming Poleta. Furthermore, we showed that the Poleta C-terminal PCNA-interacting protein motif is required for the exchange process. We also demonstrated that the second exchange step to bring back Poldelta is prohibited when Lys-164 of PCNA is monoubiquitinated. Thus the removal of the ubiquitin moiety from PCNA is likely required for the reverse exchange step after the lesion bypass synthesis by Poleta. 相似文献
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