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101.
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The transportation of sputum samples may sometimes take more than one week which results in an increased contamination rate and loss of positive cultures. The current study was planned to analyze the recovery rate of mycobacteria from transported samples with and without Cetylpyridinium chloride (CPC). Addition of CPC is useful for isolation of M. tuberculosis from sputum subjected to long-term storage.  相似文献   
103.
BackgroundStudies evaluating CYP2C19*2 and ABCB1-C3435T polymorphisms have shown conflicting results. We performed this meta-analysis to evaluate role of clinical testing for these polymorphisms in CAD patients on clopidogrel.Methods19,601 patients from 14 trials were analyzed. The endpoints were major adverse cardiovascular events (MACE), cardiovascular (CV) death, stent thrombosis (ST), myocardial infarction (MI), stroke and major bleeding. Combined relative risks (RR) with 95% confidence intervals (CI) were computed for each outcome by using standard methods of meta-analysis and test parameters were computed.ResultsCYP2C19*2 polymorphism was associated with higher risk of MACE [RR: 1.28, CI: 1.06–1.54; p = 0.009], CV death [RR: 3.21, CI: 1.65–6.23; p = 0.001], MI [RR: 1.36, CI: 1.12–1.65; p = 0.002], ST [RR: 2.41, CI: 1.69–3.41; p < 0.001]. No difference was seen in major bleeding events [RR: 1.02, CI: 0.86–1.20; p = 0.83]. Subgroup analysis showed similar results for elective PCI [RR: 1.34, CI: 1.01–1.76; p = 0.03], and PCI with DES [RR: 1.53, CI: 1.029–1.269; p = 0.03]. CYP2C19*2 polymorphism has very low sensitivity (28–58%), specificity (71–73%), positive predictive value (3–10%) but good negative predictive value (92–99%). ABCB1-C3435T polymorphism analysis revealed similar MACE [RR: 1.13, CI: 0.99–1.29; p = 0.06], ST [RR: 0.88, CI: 0.52–1.47; p = 0.63] and major bleeding [RR: 1.04, CI: 0.87–1.25; p = 0.62] in both groups.ConclusionIn CAD patients on clopidogrel therapy, CYP2C19*2 polymorphism is associated with significantly increased adverse cardiovascular events. However, due to the low positive predictive value, routine genetic testing cannot be recommended at present.  相似文献   
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Myocarditis     
Sagar S  Liu PP  Cooper LT 《Lancet》2012,379(9817):738-747
Myocarditis is an underdiagnosed cause of acute heart failure, sudden death, and chronic dilated cardiomyopathy. In developed countries, viral infections commonly cause myocarditis; however, in the developing world, rheumatic carditis, Trypanosoma cruzi, and bacterial infections such as diphtheria still contribute to the global burden of the disease. The short-term prognosis of acute myocarditis is usually good, but varies widely by cause. Those patients who initially recover might develop recurrent dilated cardiomyopathy and heart failure, sometimes years later. Because myocarditis presents with non-specific symptoms including chest pain, dyspnoea, and palpitations, it often mimics more common disorders such as coronary artery disease. In some patients, cardiac MRI and endomyocardial biopsy can help identify myocarditis, predict risk of cardiovascular events, and guide treatment. Finding effective therapies has been challenging because the pathogenesis of chronic dilated cardiomyopathy after viral myocarditis is complex and determined by host and viral genetics as well as environmental factors. Findings from recent clinical trials suggest that some patients with chronic inflammatory cardiomyopathy have a progressive clinical course despite standard medical care and might improve with a short course of immunosuppression.  相似文献   
106.
Marijuana is the most abused recreational drug in the United States. Cannabinoids, the active ingredients of marijuana, affect multiple organ systems in the human body. The pharmacologic effects of marijuana, based on stimulation of cannabinoid receptors CB1 and CB2, which are widely distributed in the cardiovascular system, have been well described. Activation of these receptors modulates the function of various cellular elements of the vessel wall, and may contribute to the pathogenesis of atherosclerosis. Clinically, there are reports linking marijuana smoking to the precipitation of angina and acute coronary syndromes. Recently, large published clinical trials with CB1 antagonist rimonabant did not show any significant benefit of this agent in preventing progression of atherosclerosis. In light of these findings and emerging data on multiple pathways linking cannabinoids to atherosclerosis, we discuss the literature on the role of cannabinoids in the pathophysiology of atherosclerosis. We also propose a marijuana paradox, which implies that inhalation of marijuana may be linked to precipitation of acute coronary syndromes, but modulation of the endocannabinoid system by a noninhalation route may have a salutary effect on the development of atherosclerosis.  相似文献   
107.
Lifelong dietary restriction (DR) is known to have many potential beneficial effects on brain function as well as delaying the onset of neurological diseases. In the present investigation, the effect of late-onset short-term intermittent fasting dietary restriction (IF-DR) regimen was studied on motor coordination and cognitive ability of ageing male rats. These animals were further used to estimate protein carbonyl content and mitochondrial complex I-IV activity in different regions of brain and peripheral organs, and the degree of age-related impairment and reversion by late-onset short-term IF-DR was compared with their levels in 3-month-old young rats. The results of improvement in motor coordination by rotarod test and cognitive skills by Morris water maze in IF-DR rats were found to be positively correlated with the decline in the oxidative molecular damage to proteins and enhanced mitochondrial complex IV activity in different regions of ageing brain as well as peripheral organs. The work was further extended to study the expression of synaptic plasticity-related proteins, such as synaptophysin, calcineurin and CaM kinase II to explore the molecular basis of IF-DR regimen to improve cognitive function. These results suggest that even late-onset short-term IF-DR regimen have the potential to retard age-associated detrimental effects, such as cognitive and motor performance as well as oxidative molecular damage to proteins.  相似文献   
108.
Significant variability in activated clotting time (ACT) measurement exists based on the type of point-of-care system used. We sought to determine the degree of agreement in ACT measurements by the Hemochron Response and the Hemochron Signature Elite Whole Blood coagulation systems and whether these 2 systems can be used interchangeably. We prospectively compared 126-paired samples in 77 patients undergoing percutaneous coronary intervention. ACT was measured for each sample using the Hemochron Response system with glass test tubes and the Hemochron Signature Elite system with low-range ACT cuvettes simultaneously. We used correlation and Bland-Altman analyses. Mean age of the study cohort was 67 ± 11 years, 49% were women, and 65% of measurements were made after systemic anticoagulation. There was a significant correlation between the Hemochron Response and Hemochron Signature Elite systems (r = 0.84, p <0.01). However, the mean bias for the ACT measurement was 9 seconds (95% confidence interval -69 to 86). In the therapeutic range of ACT measurements, the mean bias was 15 seconds (95% confidence interval -60 to 91). Thirty-three percent of total samples had >10% disagreement and 8% of samples had >20% disagreement in the ACTs measured with the Hemochron Response compared to the Hemochron Signature Elite. In conclusion, the Hemochron Response and Hemochron Signature Elite ACT values cannot be used interchangeably. Institutions using these 2 devices should be cognizant of this difference for ensuring patient safety.  相似文献   
109.
Poor patients in developing countries may not receive permanent pacemakers (PPMs) even as lifesaving measures because of their high cost. In this report we examined whether PPMs that were explanted and donated by funeral homes in the United States could be safely and effectively reused in indigent patients in India. With permission from the deceased patients' families, 121 PPMs were explanted and donated by funeral homes for reuse. These PPMs were sterilized and sent for implantation in needy and indigent patients at a charity hospital in Mumbai, India. From the pool of donated 121 PPMs, 53 (88%, 11 single-chamber PPMs, 21%, and 42 dual-chamber PPMs, 79%) were acceptable for reuse and implanted (37 new implants, 70%, and 16 for battery/generator replacement, 30%) in 53 patients (mean ± SD 64 ± 10 years old, 28 women, 53%). Indications for PPM implantation were complete heart block (n = 27, 51%) and sick sinus syndrome (n = 26, 49%). All patients were alive and well postoperatively. No significant complications including infections or device failures occurred over 19 to 1,827 days (mean 661) of follow-up. Of 40 patients (75%) who were followed locally, 4 (10%) died because of nonpacemaker-related causes; time to death was 121 to 750 days (mean 430) after PPM implantation. All except 2 patients (5%) reported marked improvement in their symptoms. There were only 4 patients (8%) who were previously employed, and all were able to resume their manual labor work. Also, of the women, 27 patients (96%) reported improvement in symptoms enabling them to resume regular household chores as housewives after PPM implantation. In conclusion, with proper device sterilization and handling protocols, reuse of explanted PPMs in poor patients in developing countries is safe and effective. Implantation of donated PPMs can not only save lives but also improve quality of life of needy poor patients.  相似文献   
110.
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