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Aortic pathology from protein kinase G activation is prevented by an antioxidant vitamin B12 analog.
People heterozygous for an activating mutation in protein kinase G1 (PRKG1, p.Arg177Gln) develop thoracic aortic aneurysms and dissections (TAAD) as young adults. Here we report that mice heterozygous for the mutation have a three-fold increase in basal protein kinase G (PKG) activity, and develop age-dependent aortic dilation. Prkg1R177Q/+ aortas show increased smooth muscle cell apoptosis, elastin fiber breaks, and oxidative stress compared to aortas from wild type littermates. Transverse aortic constriction (TAC)-to increase wall stress in the ascending aorta-induces severe aortic pathology and mortality from aortic rupture in young mutant mice. The free radical-neutralizing vitamin B12-analog cobinamide completely prevents age-related aortic wall degeneration, and the unrelated anti-oxidant N-acetylcysteine ameliorates TAC-induced pathology. Thus, increased basal PKG activity induces oxidative stress in the aorta, raising concern about the widespread clinical use of PKG-activating drugs. Cobinamide could be a treatment for aortic aneurysms where oxidative stress contributes to the disease, including Marfan syndrome
Robust automatic mapping algorithms in a network monitoring scenario
Automatically generating maps of a measured variable of interest can be problematic. In this work we focus on the monitoring network context where observations are collected and reported by a network of sensors, and are then transformed into interpolated maps for use in decision making. Using traditional geostatistical methods, estimating the covariance structure of data collected in an emergency situation can be difficult. Variogram determination, whether by method-of-moment estimators or by maximum likelihood, is very sensitive to extreme values. Even when a monitoring network is in a routine mode of operation, sensors can sporadically malfunction and report extreme values. If this extreme data destabilises the model, causing the covariance structure of the observed data to be incorrectly estimated, the generated maps will be of little value, and the uncertainty estimates in particular will be misleading. Marchant and Lark [2007] propose a REML estimator for the covariance, which is shown to work on small data sets with a manual selection of the damping parameter in the robust likelihood. We show how this can be extended to allow treatment of large data sets together with an automated approach to all parameter estimation. The projected process kriging framework of Ingram et al. [2007] is extended to allow the use of robust likelihood functions, including the two component Gaussian and the Huber function. We show how our algorithm is further refined to reduce the computational complexity while at the same time minimising any loss of information. To show the benefits of this method, we use data collected from radiation monitoring networks across Europe. We compare our results to those obtained from traditional kriging methodologies and include comparisons with Box-Cox transformations of the data. We discuss the issue of whether to treat or ignore extreme values, making the distinction between the robust methods which ignore outliers and transformation methods which treat them as part of the (transformed) process. Using a case study, based on an extreme radiological events over a large area, we show how radiation data collected from monitoring networks can be analysed automatically and then used to generate reliable maps to inform decision making. We show the limitations of the methods and discuss potential extensions to remedy these
A phase I, dose-escalation study of volasertib combined with nintedanib in advanced solid tumors
Background: Volasertib is a potent and selective cell-cycle kinase inhibitor that induces mitotic arrest and apoptosis by targeting Polo-like kinases. This study determined the maximum tolerated dose (MTD) and pharmacokinetics of volasertib combined with nintedanib, a potent and orally bioavailable triple angiokinase inhibitor, in patients with advanced solid tumors. Patients and methods: This open-label, dose-escalation trial recruited patients with advanced metastatic solid tumors following failure of conventional treatment (NCT01022853; Study 1230.7). Volasertib was administered by intravenous infusion over 2 h, starting at 100 mg in the first dose cohort. Nintedanib was administered orally at a dose of 200 mg twice daily. The first treatment cycle comprised 28 days (days 1-7 and days 9-28: nintedanib; day 8: volasertib). From cycle 2 onwards, volasertib was administered on day 1 of a 21-day cycle and nintedanib was administered days 2-21. The primary objective was the MTD of volasertib in combination with nintedanib. Results: Thirty patients were treated. The MTD of volasertib plus fixed-dose nintedanib was 300 mg once every 3 weeks, the same as the recommended single-agent dose of volasertib in solid tumors. Two of 12 assessable patients treated with the MTD experienced dose-limiting toxicities [grade 3 increased alanine aminotransferase (ALT); grade 3 ALT increase and grade 3 increased aspartate aminotransferase]. Disease control [stable disease (SD)/partial response (PR)/complete response (CR)] was achieved in 18 patients (60%): 1 CR (breast cancer), 1 PR (nonsmall-cell lung cancer), and 16 patients with SD. Volasertib showed that multiexponential pharmacokinetic behavior and co-administration of nintedanib had no significant effects on its exposure. Conclusions: Volasertib could be combined with fixed-dose nintedanib at the recommended single-agent dose. At this dose, the combination had a manageable safety profile without unexpected or overlapping adverse events, and showed antitumor activity
Identification of a ras-related protein in murine erythroleukemia cells that is a cAMP-dependent protein kinase substrate and is phosphorylated during chemically induced differentiation
Murine erythroleukemia (MEL) cells deficient in cAMP-dependent protein kinase (A-kinase) activity are impaired in chemically induced differentiation (Pilz, R. B., Eigenthaler, M., and Boss, G. R. (1992) J. Biol. Chem. 267, 16161-16167). We identified by two-dimensional polyacrylamide gel electrophoresis two lonv molecular weight proteins (referred to as pp 21-1 and 21-2) that were phosphorylated when parental MEL cells, but not A-kinase-deficient MEL cells, were treated with the membrane-permeable cAMP analog 8-bromo-cAMP. We showed that pp 21-1 and 21-2: (a) were direct A-kinase substrates; (b) bound GTP; and (c) belonged to the ras superfamily of proteins
Inspection of Computed Tomography (CT) Data and Finite Element (FE) Simulation of Additive Manufactured (AM) Components
This is the author accepted manuscript. The final version is available from the publisherOne of the challenges of working with Additive Manufactured (AM) metal parts involves checking accuracy and
reliability before production. Techniques used Computed Tomography (CT) scans, 3D image processing, and
Finite Element (FE) simulation help detect problems prior to costly faults. A workflow has been developed by
Synopsys, ANSYS, North Star Imaging, and the University of Pittsburgh to streamline this often-complex
process, with applications to analyzing metal AM-produced lightweight brackets and a component from Moog,
Inc. Software like Synopsys Simplewareâ„¢ is used to generate robust models from 3D scans of AM parts to
compare original CAD models with ‘as-built’ geometries, and to export a FE mesh for simulation in ANSYS.
This method enables identification of design deviations early in the design process, and how their impact might
be tackled prior to production. For the Moog application, unexpected defects were identified for aerospace parts
to inform future design iteration
Can vitamin D deficiency cause diabetes and cardiovascular diseases? Present evidence and future perspectives
Several studies have shown that vitamin D may play a role in many biochemical mechanisms in addition to bone and calcium metabolism. Recently, vitamin D has sparked widespread interest because of its involvement in the homeostasis of the cardiovascular system. Hypovitaminosis D has been associated with obesity, related to trapping in adipose tissue due to its lipophilic structure. In addition, vitamin D deficiency is associated with increased risk of cardiovascular disease (CVD) and this may be due to the relationship between low vitamin D levels and obesity, diabetes mellitus, dyslipidaemia, endothelial dysfunction and hypertension. However, although vitamin D has been identified as a potentially important marker of CVD, the mechanisms through which it might modulate cardiovascular risk are not fully understood. Given this background, in this work we summarise clinical retrospective and prospective observational studies linking vitamin D levels with cardio-metabolic risk factors and vascular outcome. Moreover, we review various randomised controlled trials (RCTs) investigating the effects of vitamin D supplementation on surrogate markers of cardiovascular risk. Considering the high prevalence of hypovitaminosis D among patients with high cardiovascular risk, vitamin D replacement therapy in this population may be warranted; however, further RCTs are urgently needed to establish when to begin vitamin D therapy, as well as to determine the dose and route and duration of administration. © 2011 Elsevier B.V
Effect of eplerenone on parathyroid hormone levels in patients with primary hyperparathyroidism: a randomized, double-blind, placebo-controlled trial
<p>Abstract</p> <p>Background</p> <p>Increasing evidence suggests the bidirectional interplay between parathyroid hormone and aldosterone as an important mechanism behind the increased risk of cardiovascular damage and bone disease observed in primary hyperparathyroidism. Our primary object is to assess the efficacy of the mineralocorticoid receptor-blocker eplerenone to reduce parathyroid hormone secretion in patients with parathyroid hormone excess.</p> <p>Methods/design</p> <p>Overall, 110 adult male and female patients with primary hyperparathyroidism will be randomly assigned to eplerenone (25 mg once daily for 4 weeks and 4 weeks with 50 mg once daily after dose titration] or placebo, over eight weeks. Each participant will undergo detailed clinical assessment, including anthropometric evaluation, 24-h ambulatory arterial blood pressure monitoring, echocardiography, kidney function and detailed laboratory determination of biomarkers of bone metabolism and cardiovascular disease.</p> <p>The study comprises the following exploratory endpoints: mean change from baseline to week eight in (1) parathyroid hormone(1–84) as the primary endpoint and (2) 24-h systolic and diastolic ambulatory blood pressure levels, NT-pro-BNP, biomarkers of bone metabolism, 24-h urinary protein/albumin excretion and echocardiographic parameters reflecting systolic and diastolic function as well as cardiac dimensions, as secondary endpoints.</p> <p>Discussion</p> <p>In view of the reciprocal interaction between aldosterone and parathyroid hormone and the potentially ensuing target organ damage, the EPATH trial is designed to determine whether eplerenone, compared to placebo, will effectively impact on parathyroid hormone secretion and improve cardiovascular, renal and bone health in patients with primary hyperparathyroidism.</p> <p>Trial registration</p> <p>ISRCTN33941607</p
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