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Burnett Upchurch posted an update 3 months, 2 weeks ago
Loss of telethonin from the cardiac Z-disc was accompanied by proteasomal degradation; however, unfolded telethonin accumulated in the cytoplasm, leading to a proteo-toxic response in the mice.We show that the titin A178D missense variant is pathogenic in homozygous mice, resulting in cardiomyopathy. We also provide evidence of the disease mechanism because the titin A178D variant abolishes binding of telethonin, this leads to its abnormal cytoplasmic accumulation. Subsequent degradation of telethonin by the proteasome results in proteasomal overload, and activation of a proteo-toxic response. The latter appears to be a driving factor for the cardiomyopathy observed in the mouse model.The use of in vitro assays to inform decision-making requires robust and reproducible results across studies, laboratories, and time. Experiments using positive control materials are an integral component of an assay procedure to demonstrate the extent to which the measurement system is performing as expected. This paper reviews ten characteristics that should be considered when selecting a positive control material for an in vitro assay 1) the biological mechanism of action, 2) ease of preparation, 3) chemical purity, 4) verifiable physical properties, 5) stability, 6) ability to generate responses spanning the dynamic range of the assay, 7) technical or biological interference, 8) commercial availability, 9) user toxicity, and 10) disposability. Examples and a case study of the monocyte activation test are provided to demonstrate the application of these characteristics for identification and selection of potential positive control materials. Because specific positive control materials are often written into testing standards for in vitro assays, selection of the positive control material based on these characteristics can aid in ensuring the long-term relevance and usability of these standards.Pre-competitive data sharing can offer the pharmaceutical industry significant benefits in terms of reducing the time and costs involved in getting a new drug to market through more informed testing strategies and knowledge gained by pooling data. If sufficient data is shared and can be co-analyzed, then it can also offer the potential for reduced animal usage and improvements in the in silico prediction of toxicological effects. Data sharing benefits can be further enhanced by applying the FAIR Guiding Principles, reducing time spent curating, transforming and aggregating datasets and allowing more time for data mining and analysis. We hope to facilitate data sharing by other organizations and initiatives by describing lessons learned as part of the Enhancing TRANslational SAFEty Assessment through Integrative Knowledge Management (eTRANSAFE) project, an Innovative Medicines Initiative (IMI) partnership which aims to integrate publicly available data sources with proprietary preclinical and clinical data donated by pharmaceutical organizations. Methods to foster trust and overcome non-technical barriers to data sharing such as legal and IPR (intellectual property rights) are described, including the security requirements that pharmaceutical organizations generally expect to be met. We share the consensus achieved among pharmaceutical partners on decision criteria to be included in internal clearance procedures used to decide if data can be shared. We also report on the consensus achieved on specific data fields to be excluded from sharing for sensitive preclinical safety and pharmacology data that could otherwise not be shared.
Aortic wall thrombus (AWT) can affect suitability to endovascular repair, while its most aggressive entity is better known as shaggy aorta syndrome. Primary objective was to study the procedural and clinical outcome with regard to atherothrombotic AWT in transfemoral aortic valve implantation.
In a retrospective, single-centre analysis, a qualitative 0-10 AWT score classification system was used. The most severely affected aortic area in computed tomography angiography cross-section was assessed for the number of affected segments, thrombus type, thickness, area and circumference. Primary endpoints were 30-day mortality, neurologic, renal and pulmonary events and signs of solid organ infarction.
Between November 2017 and September 2019, 604 patients underwent transfemoral transcatheter aortic valve implantation in our institution. Computed tomography-guided analysis revealed AWT in 11.3% and shaggy aorta syndrome in 6 patients (1.0% with 83.3% male). AWT was mainly present in the descending thoracic and likely using balloon-expandable devices. buy Pirinixic Our results imply important changes with regard to device design and present international transcatheter aortic valve implantation guidelines.
The concept of proportionate/disproportionate functional mitral regurgitation (FMR) has been limited by the lack of a simple way to assess it and by the paucity of data showing its prognostic superiority. The aim of this study was to evaluate the prognostic value of an individualized method of assessing FMR proportionality.
We retrospectively identified 572 patients with at least mild FMR and reduced left ventricular ejection fraction (<50%) under medical therapy. To determine FMR proportionality status, we used an approach where a simple equation determined the individualized theoretical regurgitant volume (or effective regurgitant orifice area) threshold associated with haemodynamically significant FMR. Then, we compared the measured with the theoretical value to categorize the population into non-severe, proportionate, and disproportionate FMR. The primary endpoint was all-cause mortality. During a median follow-up of 3.8 years (interquartile range 1.8-6.2), 254 patients died. The unadjusted mortality incidence per 100 persons-year rose as the degree of FMR disproportionality worsened. On multivariable analysis, disproportionate FMR remained independently associated with all-cause mortality [adjusted hazard ratio 1.785; 95% confidence interval (CI) 1.249-2.550; P = 0.001]. The FMR proportionality concept showed greater discriminative power (C-statistic 0.639; 95% CI 0.597-0.680) than the American (C-statistic 0.583; 95% CI 0.546-0.621; P for comparison <0.001) and European guidelines (C-statistic 0.584; 95% CI 0.547-0.620; P for comparison <0.001). When added to any of the before-mentioned guidelines, FMR proportionality also improved risk stratification by reclassifying patients into lower and higher risk subsets.
Disproportionate FMR is independently associated with all-cause mortality and improves the risk stratification of current guidelines.
Disproportionate FMR is independently associated with all-cause mortality and improves the risk stratification of current guidelines.