Intravenous magnesium prevents atrial fibrillation after coronary artery bypass grafting: a meta-analysis of 7 double-blind, placebo-controlled, randomized clinical trials

<p>Abstract</p> <p>Background</p> <p>Postoperative atrial fibrillation (POAF) is the most common complication after coronary artery bypass grafting (CABG). The preventive effect of magnesium on POAF is not well known. This meta-analysis was undertaken to assess the efficacy of intravenous magnesium on the prevention of POAF after CABG.</p> <p>Methods</p> <p>Eligible studies were identified from electronic databases (Medline, Embase, and the Cochrane Library). The primary outcome measure was the incidence of POAF. The meta-analysis was performed with the fixed-effect model or random-effect model according to heterogeneity.</p> <p>Results</p> <p>Seven double-blind, placebo-controlled, randomized clinical trials met the inclusion criteria including 1,028 participants. The pooled results showed that intravenous magnesium reduced the incidence of POAF by 36% (RR 0.64; 95% confidence interval (CI) 0.50-0.83; <it>P </it>= 0.001; with no heterogeneity between trials (heterogeneity <it>P </it>= 0.8, <it>I</it>²= 0%)).</p> <p>Conclusions</p> <p>This meta-analysis indicates that intravenous magnesium significantly reduces the incidence of POAF after CABG. This finding encourages the use of intravenous magnesium as an alternative to prevent POAF after CABG. But more high quality randomized clinical trials are still need to confirm the safety.</p

Effect of sibutramine on cardiovascular outcomes in overweight and obese subjects.

BACKGROUND: The long-term effects of sibutramine treatment on the rates of cardiovascular events and cardiovascular death among subjects at high cardiovascular risk have not been established. METHODS: We enrolled in our study 10,744 overweight or obese subjects, 55 years of age or older, with preexisting cardiovascular disease, type 2 diabetes mellitus, or both to assess the cardiovascular consequences of weight management with and without sibutramine in subjects at high risk for cardiovascular events. All the subjects received sibutramine in addition to participating in a weight-management program during a 6-week, single-blind, lead-in period, after which 9804 subjects underwent random assignment in a double-blind fashion to sibutramine (4906 subjects) or placebo (4898 subjects). The primary end point was the time from randomization to the first occurrence of a primary outcome event (nonfatal myocardial infarction, nonfatal stroke, resuscitation after cardiac arrest, or cardiovascular death). RESULTS: The mean duration of treatment was 3.4 years. The mean weight loss during the lead-in period was 2.6 kg; after randomization, the subjects in the sibutramine group achieved and maintained further weight reduction (mean, 1.7 kg). The mean blood pressure decreased in both groups, with greater reductions in the placebo group than in the sibutramine group (mean difference, 1.2/1.4 mm Hg). The risk of a primary outcome event was 11.4% in the sibutramine group as compared with 10.0% in the placebo group (hazard ratio, 1.16; 95% confidence interval [CI], 1.03 to 1.31; P=0.02). The rates of nonfatal myocardial infarction and nonfatal stroke were 4.1% and 2.6% in the sibutramine group and 3.2% and 1.9% in the placebo group, respectively (hazard ratio for nonfatal myocardial infarction, 1.28; 95% CI, 1.04 to 1.57; P=0.02; hazard ratio for nonfatal stroke, 1.36; 95% CI, 1.04 to 1.77; P=0.03). The rates of cardiovascular death and death from any cause were not increased. CONCLUSIONS: Subjects with preexisting cardiovascular conditions who were receiving long-term sibutramine treatment had an increased risk of nonfatal myocardial infarction and nonfatal stroke but not of cardiovascular death or death from any cause. (Funded by Abbott; ClinicalTrials.gov number, NCT00234832.

Erratum: a healable supramolecular polymer blend based on aromatic π-πStacking and hydrogen bonding interactions (J. Am. Chem. Soc. (2010) 132:34 (12051-12058) DOI: 10.1021/ja104446r)

It has been brought to our attention that the values of tensile modulus and modulus of toughness in this paper were calculated incorrectly, using percentage elongation rather than the fractional change in the original sample length. The quoted values of tensile modulus are thus understated by a factor of 102, and values for modulus of toughness are overstated by the same factor. The experimental stress−strain plots given in the paper (Figures 11a and 13) are correct, and the paper’s conclusions remain valid as these are based on relative material parameters before and after healing, rather than on absolute values. However, we now provide corrected versions of Figures 10 and 11, and of the TOC Graphic, and specific text corrections are given below. The Supporting Information remains unchanged.</p

Erratum: a healable supramolecular polymer blend based on aromatic π-πStacking and hydrogen bonding interactions (J. Am. Chem. Soc. (2010) 132:34 (12051-12058) DOI: 10.1021/ja104446r)

It has been brought to our attention that the values of tensile modulus and modulus of toughness in this paper were calculated incorrectly, using percentage elongation rather than the fractional change in the original sample length. The quoted values of tensile modulus are thus understated by a factor of 102, and values for modulus of toughness are overstated by the same factor. The experimental stress−strain plots given in the paper (Figures 11a and 13) are correct, and the paper’s conclusions remain valid as these are based on relative material parameters before and after healing, rather than on absolute values. However, we now provide corrected versions of Figures 10 and 11, and of the TOC Graphic, and specific text corrections are given below. The Supporting Information remains unchanged.</p

Structural mechanism underlying capsaicin binding and activation of the TRPV1 ion channel.

Capsaicin bestows spiciness by activating TRPV1 channel with exquisite potency and selectivity. Although a capsaicin-bound channel structure was previously resolved by cryo-EM at 4.2- to 4.5-Å resolution, capsaicin was registered as a small electron density, reflecting neither its chemical structure nor specific ligand-channel interactions--important details required for mechanistic understanding. We obtained the missing atomic-level details by iterative computation and confirmed them by systematic site-specific functional tests. We observed that the bound capsaicin takes a 'tail-up, head-down' configuration. The vanillyl and amide groups form specific interactions to anchor its bound position, while the aliphatic tail may sample a range of conformations, making it invisible in cryo-EM images. Capsaicin stabilizes TRPV1's open state by 'pull-and-contact' interactions between the vanillyl group and the S4-S5 linker. Our study provides a structural mechanism for the agonistic function of capsaicin and its analogs, and demonstrates an effective approach to obtain atomic-level information from cryo-EM structures