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Amphibole has been discussed to potentially represent an important phase during early chemical evolution of arc magmas, but is not commonly observed in eruptive arc rocks. Here, we present an in-depth study of metastable calcic amphibole megacrysts in basaltic andesites of Merapi volcano, Indonesia. Radiogenic Sr and Nd isotope compositions of the amphibole megacrysts overlap with the host rock range, indicating that they represent antecrysts to the host magmas rather than xenocrysts. Amphibole-based barometry suggests that the megacrysts crystallised at pressures of >500 MPa, i.e., in the mid- to lower crust beneath Merapi. Rare-earth element concentrations, in turn, require the absence of magmatic garnet in the Merapi feeding system and, therefore, place an uppermost limit for the pressure of amphibole crystallisation at ca. 800 MPa. The host magmas of the megacrysts seem to have fractionated significant amounts of amphibole and/or clinopyroxene, because of their low Dy/Yb ratios relative to the estimated compositions of the parent magmas to the megacrysts. The megacrysts' parent magmas at depth may thus have evolved by amphibole fractionation, in line with apparently coupled variations of trace element ratios in the megacrysts, such as e.g., decreasing Zr/Hf with Dy/Yb. Moreover, the Th/U ratios of the amphibole megacrysts decrease with increasing Dy/Yb and are lower than Th/U ratios in the basaltic andesite host rocks. Uranium in the megacrysts' parent magmas, therefore, may have occurred predominantly in the tetravalent state, suggesting that magmatic fO in the Merapi plumbing system increased from below the FMQ buffer in the mid-to-lower crust to 0.6-2.2 log units above it in the near surface environment. In addition, some of the amphibole megacrysts experienced dehydrogenation (H loss) and/or dehydration (HO loss), as recorded by their variable HO contents and D/ H and Fe/Fe ratios, and the release of these volatile species into the shallow plumbing system may facilitate Merapi's often erratic eruptive behaviour. [ABSTRACT FROM AUTHOR]

The article presents the author's conclusion on the effect of angiotensin receptor blockers (ARBs) in preventing the progression of atherosclerosis in patients with coronary artery disease. Topics include the study of percutaneous coronary intervention procedures for culprit lesions, percutaneous coronary revascularization, and drug therapy trials for patients with heart failure.

Background and objective: Results from the VALVACE (VALsartan Versus ACE inhibition after bare metal stent implantation) trial suggest that prevention of in-stent restenosis after implantation of bare-metal stents in type B2/C coronary artery lesions is possible after administration of valsartan 80 mg/day. However, the restenosis rate in patients with stable angina was relatively high (27%) with this dosage and no different from patients taking ACE inhibitors. Therefore, a 1 : 1 matched comparison on a case-control basis was initiated in a prospective controlled registry using a higher dose of valsartan, 160-320 mg/day. Methods: A total of 450 patients (241 men, mean age 62.7 ± 9.1 years) with matched demographic and angiographic characteristics to patients in the VALVACE trial were treated with high-dose oral valsartan 160-320 mg/day over 6 months until control angiography. Angiographic restenosis rate, target lesion revascularization (TLR) and target vessel revascularization (TVR) rates, major adverse cardiac event (MACE) rate (death, myocardial infarction, and stent thrombosis) and mean late lumen loss were analysed after 6 months. Results were compared with the results of the VALVACE trial. Analysis of the combined results of the current study together with the VALVACE trial data enabled calculation of the gender- and dose-dependent effects of valsartan. Results: In the high-dose valsartan group, the angiographic restenosis rate in 368 patients with control angiography was 7.3% compared with 19.5% in the low-dose group (VALVACE) [p < 0.0001]. Mean late lumen loss was 0.37 ± 0.3 mm in the high-dose group compared with 0.53 ± 0.31 mm in the VALVACE trial (p < 0.01). TLR and TVR rates were 4.3% in the high-dose group compared with 9% in the VALVACE trial (p < 0.01). The MACE rate was 0% in the high-dose group compared with 1.5% in the VALVACE trial (p < 0.01). Summarizing the data for valsartan, the in-stent restenosis rates in men were 22.7%, 13.3%, 6.7%, and 5.4% in patients receiving 80, 160, 240, and 320 mg/day, respectively. In women, the in-stent restenosis rates were 13.3% and 6.3% in patients receiving 80 and 160 mg/day, respectively; no restenosis occurred in patients receiving higher doses. Conclusion: Administration of high-dose oral valsartan 160-320 mg/day after implantation of bare-metal stent in type B2/C coronary artery lesions reduces angiographic in-stent restenosis, TLR, TVR, late lumen loss, and MACE rates more effectively than low-dose valsartan 80 mg/day. [ABSTRACT FROM AUTHOR]

The aim of this systematic review and meta-analysis was (1) to determine exercise effects on bone mineral density (BMD) in postmenopausal women and (2) to address the corresponding implication of bone and menopausal status or supervision in postmenopausal women. A comprehensive search of eight electronic databases according to the PRISMA statement up to August 9, 2022, included controlled exercise trials ≥ 6 months. BMD changes (standardized mean differences: SMD) at the lumbar spine (LS), femoral neck (FN), and total hip (TH) were considered as outcomes. Study group comparisons were conducted for osteopenia/osteoporosis versus normal BMD, early versus late postmenopausal women, and predominantly supervised versus predominantly non-supervised study arms. We applied an inverse heterogeneity (IVhet) model. In summary, 80 studies involving 94 training and 80 control groups with a pooled number of 5581 participants were eligible. The IVhet model determined SMDs of 0.29 (95% CI: 0.16–0.42), 0.27 (95% CI: 0.16–0.39), and 0.41 (95% CI: 0.30–0.52) for LS, FN, and THBMD, respectively. Heterogeneity between the trial results varied from low (I2 = 20%, TH BMD) to substantial (I2 = 68%, LS-BMD). Evidence for publication bias/small study effects was negligibly low (FN-, TH-BMD) to high (LSBMD). We observed no significant differences (p >.09) for exercise effects on LS-, FN-, or TH-BMD-LS between studies/study arms with or without osteopenia/osteoporosis, early versus late postmenopausal women, or predominantly supervised versus non-supervised exercise programs. Using robust statistical methods, the present work provides further evidence for a positive effect of exercise on BMD in postmenopausal women. Differences in bone status (osteopenia/osteoporosis versus normal bone), menopausal status (early versus late postmenopausal), and supervision (yes versus no) did not significantly affect the exercise effects on BMD at LS or proximal femur. [ABSTRACT FROM AUTHOR]

Summary: The role of exercise in preventing osteoporotic fractures is vague, and further recommendations for optimized exercise protocols are very rare. In the present work, we provided positive evidence for exercise effects on the number of osteoporotic fractures in adults, albeit without observing any significant relevance of intensity progression or study duration. Introduction : Osteoporotic fractures are a major challenge confronting our aging society. Exercise might be an efficient agent for reducing osteoporotic fractures in older adults, but the most promising exercise protocol for that purpose has yet to be identified. The present meta-analysis thus aimed to identify important predictors of the exercise effect on osteoporotic fractures in adults. Methods: We conducted a systematic search of six literature databases according to the PRISMA guideline that included controlled exercise studies and reported the number of low-trauma major osteoporotic fractures separately for exercise (EG) and control (CG) groups. Primary study outcome was incidence ratio (IR) for major osteoporotic fractures. Sub-analyses were conducted for progression of intensity (yes vs. no) during the trial and the study duration (≤ 12 months vs. > 12 months). Results: In summary, 11 studies with a pooled number of 9715 participant-years in the EG and 9592 in the CG were included. The mixed-effects conditional Poisson regression revealed positive exercise effects on major osteoporotic fractures (RR: 0.75, 95% CI: 0.54–0.94, p =.006). Although studies with intensity progression were more favorable, our subgroup analysis did not determine significant differences for diverging intensity progression (p =.133) or study duration (p =.883). Heterogeneity among the trials of the subgroups (I2 ≤ 0–7.1%) was negligible. Conclusion: The present systematic review and meta-analysis provided significant evidence for the favorable effect of exercise on major osteoporotic fractures. However, diverging study and exercise characteristics along with the close interaction of exercise parameters prevented the derivation of reliable recommendations for exercise protocols for fracture reductions. PROSPERO ID: CRD42021250467. [ABSTRACT FROM AUTHOR]

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is associated with fibrofatty replacement of cardiac myocytes, ventricular tachyarrhythmias and sudden cardiac death. In 32 of 120 unrelated individuals with ARVC, we identified heterozygous mutations in PKP2, which encodes plakophilin-2, an essential armadillo-repeat protein of the cardiac desmosome. In two kindreds with ARVC, disease was incompletely penetrant in most carriers of PKP2 mutations. [ABSTRACT FROM AUTHOR]