Lipid profile and left ventricular geometry pattern in obese children

Background: Left ventricular hypertrophy (LVH) is an important risk factor for cardiovascular and all-cause mortality. Previous studies reported conflicting results concerning the relationship between serum lipid levels and left ventricular geometry pattern. We sought to explore the relationship between standard serum lipid profile measures with left ventricular geometry pattern in obese children. Patients and methods: In this cross-sectional study, a total of 70 obese children were examined. Fasting blood samples were taken to measure total cholesterol, low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), triglycerides (TGs), glucose, and insulin. Based on these values TG/HDL ratio, BMI and HOMA index were calculated. We also measured the average 24-h ambulatory systolic blood pressure (SBP) and two-dimensional (2/D) transthoracic echocardiography was performed to determine left ventricular mass index (LVMI) and relative wall thickness (RWT). Multiple regression analyses were conducted to explore relationships between study variables and the LVMI or RWT as outcome variables. The final model with LVMI included TG/HDL ratio, BMI, 24 h-average SBP, age and sex, while for the RWT we included BMI, insulin, age and sex. Results: Our study included 70 children (65.71% boys and 34.29% girls) median age (14 years, IQR = 12-16)." We demonstrated independent and positive association of TG/HDL ratio, BMI and 24 h-average SBP with LVMI (effect = 3.65, SE = 1.32, p < 0.01; effect = 34.90, SE = 6.84, p < 0.01; effect = 0.32, SE = 0.12, p < 0.01, respectively). On the other hand, in model with RWT as outcome variable, only BMI and insulin were significantly linked (BMI: effect = 13.07, SE = 5.02, p = 0.01 Insulin: effect = 2.80, SE = 0.97). Conclusion: Increased TG/HDL ratio in obese children is associated with the development of eccentric left ventricular hypertrophy while increased BMI and insulin were associated with concentric left ventricular hypertophy

Reexamination of a Meta-Analysis of the Effect of Antioxidant Supplementation on Mortality and Health in Randomized Trials

A recent meta-analysis of selected randomized clinical trials (RCTs), in which population groups of differing ages and health status were supplemented with various doses of β-carotene, vitamin A, and/or vitamin E, found that these interventions increased all-cause mortality. However, this meta-analysis did not consider the rationale of the constituent RCTs for antioxidant supplementation, none of which included mortality as a primary outcome. As the rationale for these trials was to test the hypothesis of a potential benefit of antioxidant supplementation, an alternative approach to a systematic evaluation of these RCTs would be to evaluate this outcome relative to the putative risk of greater total mortality. Thus, we examined these data based on the primary outcome of the 66 RCTs included in the meta-analysis via a decision analysis to identify whether the results provided a positive (i.e., benefit), null or negative (i.e., harm) outcome. Our evaluation indicated that of these RCTs, 24 had a positive outcome, 39 had a null outcome, and 3 had a negative outcome. We further categorized these interventions as primary (risk reduction in healthy populations) or secondary (slowing pathogenesis or preventing recurrent events and/or cause-specific mortality) prevention or therapeutic (treatment to improve quality of life, limit complications, and/or provide rehabilitation) studies, and determined positive outcomes in 8 of 20 primary prevention studies, 10 of 34 secondary prevention studies, and 6 out of 16 therapeutic studies. Seven of the eight RCTs with a positive outcome in primary prevention included participants in a population where malnutrition is frequently described. These results suggest that analyses of potential risks from antioxidant supplementation should be placed in the context of a benefit/risk ratio

A Generalization of Quantum Stein's Lemma

We present a generalization of quantum Stein's Lemma to the situation in which the alternative hypothesis is formed by a family of states, which can moreover be non-i.i.d.. We consider sets of states which satisfy a few natural properties, the most important being the closedness under permutations of the copies. We then determine the error rate function in a very similar fashion to quantum Stein's Lemma, in terms of the quantum relative entropy. Our result has two applications to entanglement theory. First it gives an operational meaning to an entanglement measure known as regularized relative entropy of entanglement. Second, it shows that this measure is faithful, being strictly positive on every entangled state. This implies, in particular, that whenever a multipartite state can be asymptotically converted into another entangled state by local operations and classical communication, the rate of conversion must be non-zero. Therefore, the operational definition of multipartite entanglement is equivalent to its mathematical definition.Comment: 30 pages. (see posting by M. Piani arXiv:0904.2705 for a different proof of the strict positiveness of the regularized relative entropy of entanglement on every entangled state). published version

Vitamin D and subsequent all-age and premature mortality: a systematic review

<br>Background: All-cause mortality in the population < 65 years is 30% higher in Glasgow than in equally deprived Liverpool and Manchester. We investigated a hypothesis that low vitamin D in this population may be associated with premature mortality via a systematic review and meta-analysis.</br> <br>Methods: Medline, EMBASE, Web of Science, the Cochrane Library and grey literature sources were searched until February 2012 for relevant studies. Summary statistics were combined in an age-stratified meta-analysis.</br> <br>Results: Nine studies were included in the meta-analysis, representing 24,297 participants, 5,324 of whom died during follow-up. The pooled hazard ratio for low compared to high vitamin D demonstrated a significant inverse association (HR 1.19, 95% CI 1.12-1.27) between vitamin D levels and all-cause mortality after adjustment for available confounders. In an age-stratified meta-analysis, the hazard ratio for older participants was 1.25 (95% CI 1.14-1.36) and for younger participants 1.12 (95% CI 1.01-1.24).</br> <br>Conclusions: Low vitamin D status is inversely associated with all-cause mortality but the risk is higher amongst older individuals and the relationship is prone to residual confounding. Further studies investigating the association between vitamin D deficiency and all-cause mortality in younger adults with adjustment for all important confounders (or using randomised trials of supplementation) are required to clarify this relationship.</br&gt

Quantum capacity of an amplitude-damping channel with memory

We calculate the quantum capacity of an amplitude-damping channel with time correlated Markov noise, for two channel uses. Our results show that memory of the channel increases it's ability to transmit quantum information significantly. We analyze and compare our findings with earlier numerical results on amplitude-damping channel with memory. An upper bound on the amount of quantum information transmitted over the channel in presence of memory, for an arbitrary number of channel uses is also presented.Comment: 17 Pages, 5 Figure

Friend or foe? The current epidemiologic evidence on selenium and human cancer risk.

Scientific opinion on the relationship between selenium and the risk of cancer has undergone radical change over the years, with selenium first viewed as a possible carcinogen in the 1940s then as a possible cancer preventive agent in the 1960s-2000s. More recently, randomized controlled trials have found no effect on cancer risk but suggest possible low-dose dermatologic and endocrine toxicity, and animal studies indicate both carcinogenic and cancer-preventive effects. A growing body of evidence from human and laboratory studies indicates dramatically different biological effects of the various inorganic and organic chemical forms of selenium, which may explain apparent inconsistencies across studies. These chemical form-specific effects also have important implications for exposure and health risk assessment. Overall, available epidemiologic evidence suggests no cancer preventive effect of increased selenium intake in healthy individuals and possible increased risk of other diseases and disorders

The Antioxidant Potential of the Mediterranean Diet in Patients at High Cardiovascular Risk: An In-Depth Review of the PREDIMED

Cardiovascular disease (CVD) is the leading global cause of death. Diet is known to be important in the prevention of CVD. The PREDIMED trial tested a relatively low-fat diet versus a high-fat Mediterranean diet (MedDiet) for the primary prevention of CVD. The resulting reduction of the CV composite outcome resulted in a paradigm shift in CV nutrition. Though many dietary factors likely contributed to this effect, this review focuses on the influence of the MedDiet on endogenous antioxidant systems and the effect of dietary polyphenols. Subgroup analysis of the PREDIMED trial revealed increased endogenous antioxidant and decreased pro-oxidant activity in the MedDiet groups. Moreover, higher polyphenol intake was associated with lower incidence of the primary outcome, overall mortality, blood pressure, inflammatory biomarkers, onset of new-onset type 2 diabetes mellitus (T2DM), and obesity. This suggests that polyphenols likely contributed to the lower incidence of the primary event in the MedDiet groups. In this article, we summarize the potential benefits of polyphenols found in the MedDiet, specifically the PREDIMED cohort. We also discuss the need for further research to confirm and expand the findings of the PREDIMED in a non-Mediterranean population and to determine the exact mechanisms of action of polyphenols

Non-Antioxidant Properties of α-Tocopherol Reduce the Anticancer Activity of Several Protein Kinase Inhibitors In Vitro

The antioxidant properties of α-tocopherol have been proposed to play a beneficial chemopreventive role against cancer. However, emerging data also indicate that it may exert contrasting effects on the efficacy of chemotherapeutic treatments when given as dietary supplement, being in that case harmful for patients. This dual role of α-tocopherol and, in particular, its effects on the efficacy of anticancer drugs remains poorly documented. For this purpose, we studied here, using high throughput flow cytometry, the direct impact of α-tocopherol on apoptosis and cell cycle arrest induced by different cytotoxic agents on various models of cancer cell lines in vitro. Our results indicate that physiologically relevant concentrations of α-tocopherol strongly compromise the cytotoxic and cytostatic action of various protein kinase inhibitors (KI), while other classes of chemotherapeutic agents or apoptosis inducers are unaffected by this vitamin. Interestingly, these anti-chemotherapeutic effects of α-tocopherol appear to be unrelated to its antioxidant properties since a variety of other antioxidants were completely neutral toward KI-induced cell cycle arrest and cell death. In conclusion, our data suggest that dietary α-tocopherol could limit KI effects on tumour cells, and, by extent, that this could result in a reduction of the clinical efficacy of anti-cancer treatments based on KI molecules