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Research is presented describing the study of parallel machine scheduling problems associated with job tardiness where stochastic interruptions are prevalent.

Background: Cardiac resynchronization therapy (CRT) is a recognized treatment modality for patients with dilated cardiomyopathy (DCM), left bundle branch block, and severe cardiac failure. However, 30% of patients are "nonresponders." Intriguingly, the opposite case has not been reported until recently: Do some patients treated with CRT have a "complete" recovery and thus can be considered "hyperresponders"?Objective: The purpose of this study was to investigate patients treated with CRT who have a "complete" functional recovery, with normalization of left ventricular function after therapy.Methods: Eighty-four consecutive patients with DCM, sinus rhythm, and left bundle branch block in New York Heart Association functional class III and IV who were implanted with a CRT device were prospectively followed. Patients were considered to be "hyperresponders" if they concurrently fulfilled two criteria: functional recovery and left ventricular ejection fraction > or = 50%.Results: Among the 84 patients with DCM, 11 (13%) were "hyperresponders" within 6 to 24 months after CRT (left ventricular ejection fraction increased from 25% +/- 8% to 60% +/- 6.5%, P = .001). Comparison of baseline parameters between "hyperresponders" and the remaining patients showed that only etiology of the DCM was statistically discriminative. All "hyperresponders" belonged to the group of patients with nonischemic DCM (18% vs 0%, P = .05).Conclusion: In a subset of patients successfully implanted with a CRT device, "complete" functional recovery associated with normalization of LV function was observed, giving rise to the concept of "hyperresponders." This finding is observed exclusively in the subgroup of patients with nonischemic DCM and suggests that left bundle branch block may be the causal factor of DCM in this subgroup of patients. [ABSTRACT FROM AUTHOR]

To investigate the correlation between oxidative stress and mitochondrial damage with aging, antioxidant system, levels of oxidative DNA damage and as an index of the loss of plasma membrane integrity lipid peroxidation and membrane potential were studied. Results showed that the activities of antioxidant enzymes superoxide dismutase (SOD) and catalase significantly decreased during aging, however glutathione peroxidase (GSH-PX) increased in the aged mitochondria and glutathione (GSH) did not change during aging. No statistical difference was observed in the lipid peroxidation of mitochondria between young and old animals. The level of oxidative DNA damage (measured as 8oxo-dG) tended to increase during aging. [Copyright &y& Elsevier]

The diet is usually formed of a varying antioxidant and fatty acid content acquired from oils. The purpose of this study was to determine the effects of corn oil-rich diet supplemented or not with vitamin E on oxidative damage and antioxidant status in liver and adipose tissue of rat. Male Wistar rats were fed during 4 weeks with a hyperlipidic diet. The groups fed with hyperlipidic diets showed lower activity levels than the control groups with the exception of superoxide dismutase and glutathione peroxidase in brown adipose tissue. Supplementation of the control group with vitamin E (CE) did not produce any significant changes in the superoxide dismutase and catalase levels, but glutathione peroxidase activity increased slightly for groups supplemented with vitamin E. The hyperlipidic group supplemented with vitamin E (HE) showed a significant decrease of SOD and catalase activities in adipose tissues. Reduced glutathione levels decreased in liver from animals fed with higher quantities of corn oil. Vitamin E supplementation showed a decrease in GSH levels only for the control group (CE). Thiobarbituric acid-reactive substance (TBARS) levels were lower in the animals fed larger quantities of corn oil. Supplementation of vitamin E results in lower TBARS values. [Copyright &y& Elsevier]