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At the Institut fur Thermische Stromungsmaschinen, University of Karlsruhe (ITS), a design technology has been introduced to reduce the mechanically and especially the thermally induced stresses in ceramic components. The concept is based on a three-layered construction (outer ceramic shell heat insulating layer, and metallic core) and an optimization of the thicknesses of the single layers, in order to obtain a homogenous temperature distribution in the ceramic structure. The optimization is performed by finite element analyses in combination with failure probability calculations. This methodology has been applied to increase the reliability of a first stage Sintered Silicon Carbide (SSiC) ceramic nozzle vane of a stationary gas turbine (70 MW/1400 [degrees] C). As a result it was found that the mechanically and thermally induced loads have been reduced considerably and do not exceed 100 MPa, thus achieving adequate life based upon failure probability calculations. Even in a trip situation (fuel cutoff), when the highest loads do occur, the calculations demonstrate a significantly reduced failure probability. The results of the finite element analyses were verified by simulating the typical operating conditions after fuel cutoff in a test rig.

Data on perioperative extracorporeal membrane oxygenation (ECMO) in liver transplantation (LT) are scarce. ECMO has been used preoperatively, intraoperatively, and postoperatively for a variety of indications at our center. This retrospective, single-center study of ECMO use peri-LT aimed to describe predictors for successful outcome in this highly select cohort of patients. Demographics, support method, and indication for LT were compared between survivors and nonsurvivors. Twenty-nine patients received venovenous (V-V; n = 20), venoarterial (V-A; n = 8), and venoarteriovenous (n = 1) ECMO. Twelve (41.4%) patients were bridged to emergency LT for acute liver failure, and emergency redo LT. Four (13.3%) patients required intraoperative V-A ECMO salvage, 2 necessitating extracorporeal cardiopulmonary resuscitation. Thirteen (43.3%) patients required ECMO support after LT: V-V ECMO (n = 9); V-A ECMO (n = 1); and extracorporeal cardiopulmonary resuscitation (n = 3) between postoperative days 2 to 30. Overall, 19 patients (65.5%) were successfully weaned off ECMO; 15 (51.7%) survived to intensive care unit discharge. All patients who underwent intraoperative salvage ECMO and all who were bridged to emergency redo LT died. Peri-LT ECMO is feasible. Post-LT ECMO outcomes are encouraging, in particular for V-V ECMO. Intraoperative ECMO salvage, uncontrolled sepsis, and graft failure are associated with poor outcomes., Competing Interests: Declaration of competing interest The authors of this manuscript have no conflicts of interest to disclose as described by the American Journal of Transplantation., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Arterial thrombosis contributes to some of the most frequent causes of mortality globally, such as myocardial infarction and stroke. Platelets are essential mediators of physiological haemostasis and pathological thrombosis. Platelet activation is controlled by a multitude of signalling pathways. Upon activation, platelets shed platelet-derived extracellular vesicles (pEVs). In this Special Issue: Extracellular Vesicles, Moon et al. investigate the impact of various platelet agonists (thrombin, ADP, collagen) on the proteome of pEVs. The study demonstrates that pEVs exhibit an agonist-dependent altered proteome compared to their parent cells, with significant variations in proteins related to coagulation, complement, and platelet activation. The study observes the rapid generation of pEVs following agonist stimulation with specific proteome alterations that underscore an active packaging process. This commentary highlights the implications of their findings and discusses the role of pEV cargo in cardiovascular disease with potential novel therapeutic and diagnostic opportunities., (© 2024 The Author(s). PROTEOMICS published by Wiley‐VCH GmbH.)

Objective:  The effect of the PCSK9 (proprotein convertase subtilisin/kexin type 9) inhibitor alirocumab on platelet aggregation among patients with acute myocardial infarction (AMI) remains unknown. We aimed to explore the effect of alirocumab added to high-intensity statin therapy on P2Y12 reaction unit (PRU) among AMI patients receiving dual antiplatelet therapy (DAPT) with a potent P2Y12 inhibitor (ticagrelor or prasugrel). In addition, we assessed circulating platelet-derived noncoding RNAs (microRNAs and YRNAs)., Methods:  This was a prespecified, powered, pharmacodynamic substudy of the PACMAN trial, a randomized, double-blind trial comparing biweekly alirocumab (150 mg) versus placebo in AMI patients undergoing percutaneous coronary intervention. Patients recruited at Bern University Hospital, receiving DAPT with a potent P2Y12 inhibitor, and adherent to the study drug (alirocumab or placebo) were analyzed for the current study. The primary endpoint was PRU at 4 weeks after study drug initiation as assessed by VerifyNow P2Y12 point-of-care assays., Results:  Among 139 randomized patients, the majority of patients received ticagrelor DAPT at 4 weeks (57 [86.4%] in the alirocumab group vs. 69 [94.5%] in the placebo group, p  = 0.14). There were no significant differences in the primary endpoint PRU at 4 weeks between groups (12.5 [interquartile range, IQR: 27.0] vs. 19.0 [IQR: 30.0], p  = 0.26). Consistent results were observed in 126 patients treated with ticagrelor (13.0 [IQR: 20.0] vs. 18.0 [IQR: 27.0], p  = 0.28). Similarly, platelet-derived noncoding RNAs did not significantly differ between groups., Conclusion:  Among AMI patients receiving DAPT with a potent P2Y12 inhibitor, alirocumab had no significant effect on platelet reactivity as assessed by PRU and platelet-derived noncoding RNAs., Competing Interests: Y.U. reports personal fees from Infraredx outside the submitted work. S.L. is employed by CTU Bern, University of Bern, which has a staff policy of not accepting honoraria or consultancy fees. However, CTU Bern is involved in design, conduct, or analysis of clinical studies funded by not-for-profit and for-profit organizations. In particular, pharmaceutical and medical device companies provide direct funding to some of these studies. D.S. reports receiving personal fees from Sanofi-Aventis (Suisse) outside the submitted work. S.S. reports research grants to the institution from Edwards Lifesciences, Medtronic, Boston Scientific, and Abbott, and personal fees from Boston Scientific, Teleflex, and BTG. M.V. reports research grants to the institution from Terumo and Concept Medical and consulting fees from AstraZeneca, Terumo, Alvimedica/CID, Abiomed, Amgen, Abbott Vascular, Daiichi Sankyo, Bayer, CoreFLOW, DORSIA PHARMACEUTICALS LTD, Universität Basel Dept. Klinische Forschung, Vifor, Bristol Myers Squib SA, Biotronik, Boston Scientific, Medtronic, Vesalio, Novartis, Chiesi, PhaseBio, and ECRI, outside the submitted work. S.W. reports research and educational grants to the institution from Abbott, Abiomed, Amgen, AstraZeneca, Bayer, Biotronik, Boehringer Ingelheim, Boston Scientific, Bristol Myers Squibb, Cardinal Health, CardioValve, Corflow Therapeutics, CSL Behring, Daiichi Sankyo, Edwards Lifesciences, Guerbet, InfraRedx, Janssen-Cilag, Johnson & Johnson, Medicure, Medtronic, Merck Sharp & Dohm, Miracor Medical, Novartis, Novo Nordisk, Organon, OrPha Suisse, Pfizer, Polares, Regeneron, Sanofi-Aventis, Servier, Sinomed, Terumo, Vifor, and V-Wave. S.W. serves as unpaid advisory board member and/or unpaid member of the steering/executive group of trials funded by Abbott, Abiomed, Amgen, AstraZeneca, Bayer, Boston Scientific, Biotronik, Bristol Myers Squibb, Edwards Lifesciences, Janssen, MedAlliance, Medtronic, Novartis, Polares, Recardio, Sinomed, Terumo, V-Wave, and Xeltis, but has not received personal payments by pharmaceutical companies or device manufacturers. He is also member of the steering/executive committee group of several investigator-initiated trials that receive funding by industry without impact on his personal remuneration. M.M. is a British Heart Foundation (BHF) Chair Holder (CH/16/3/32406) with BHF program grant support (RG/F/21/110053). He is also supported by the Leducq Foundation (18CVD02) and VASCage-C (Research Centre on Vascular Aging and Stroke), an R&D K-Centre of the Austrian Research Promotion Agency (COMET program—Competence Centres for Excellent Technologies) funded by the Austrian Ministry for Transport, Innovation and Technology, the Austrian Ministry for Digital and Economic Affairs, and the federal states Tyrol, Salzburg, and Vienna with the grant number FSG 868624. He has filed and licensed patents on microRNAs as biomarkers. L.R. received a grant to the institution for the conduction of the PACMAN AMI study by Sanofi, Regeneron, and Infraredx. L.R. received research grants to the institution by Abbott, Boston Scientific, Biotronik, and Heartflow, and speaker or consultation fees by Abbott, Amgen, AstraZeneca, Canon, Novo Nordisk, Medtronic, Occlutech, and Sanofi., (Thieme. All rights reserved.)

The hip joint helps the upper body to transfer its weight to lower body. Along with age, there are various reasons for the degeneration of the hip joint. The artificial hip implant replaces the degenerated hip. Wear between the joints is the primary cause of the hip implant becoming loose. The wear can occur due to various reasons. Due to this revision surgery are most common in young and active patients. In the design phase of the implant if this is taken care then life expectancy of the implant can be improved. Small design changes can significantly enhance the implant's life. In this work, elliptical-shaped hip implant stem is designed, and linear wear is estimated at trunnion junction. In this work, a 28 mm diameter femoral head with a 4 mm thick acetabular cup and a 2 mm thick backing cup is used. The top surface taper radiuses are changed. Solid works was used to create the models. Ansys was used to perform the analysis. It was found that as the radius of the TTR decreased, the wear rate decreased. The least wear rate was found in 12/14 mm taper with a value of 1.15E -02 mm year -1 for the first material combination and with a value of 1.23E -02 mm year -1 for the second material combination. In the comparison between the models with 1 mm chamfer and no chamfer, it was found that the wear rate was lower for the models with 1 mm chamfer. When the chamfer was increased (more than 1 mm), the linear wear increased. Wear is the main reason for the loosening of hip implants, which leads to a revision of an implant. It was found that with a decrease in TTR, there was a small increase in the linear wear rate. Overall, the implant with TTR 6 mm and a chamfer of 1 mm was found to have the least wear rate. To validate these results, the implant can be 3D printed and tested on a hip simulator., (© 2023 IOP Publishing Ltd.)

The proportion of young platelets, also known as newly formed or reticulated, within the overall platelet population has been clinically correlated with adverse cardiovascular outcomes. However, our understanding of this is incomplete because of limitations in the technical approaches available to study platelets of different ages. In this study, we have developed and validated an in vivo temporal labeling approach using injectable fluorescent antiplatelet antibodies to subdivide platelets by age and assess differences in functional and molecular characteristics. With this approach, we found that young platelets (<24 hours old) in comparison with older platelets respond to stimuli with greater calcium flux and degranulation and contribute more to the formation of thrombi in vitro and in vivo. Sequential sampling confirmed this altered functionality to be independent of platelet size, with distribution of sizes of tracked platelets commensurate with the global platelet population throughout their 5-day lifespan in the circulation. The age-associated decrease in thrombotic function was accompanied by significant decreases in the surface expression of GPVI and CD31 (PECAM-1) and an increase in CD9. Platelet messenger RNA (mRNA) content also decreased with age but at different rates for individual mRNAs indicating apparent conservation of those encoding granule proteins. Our pulse-chase-type approach to define circulating platelet age has allowed timely reexamination of commonly held beliefs regarding size and reactivity of young platelets while providing novel insights into the temporal regulation of receptor and protein expression. Overall, future application of this validated tool will inform age-based platelet heterogeneity in physiology and disease., (© 2022 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)

Platelets are essential mediators of physiological hemostasis and pathological thrombosis. Currently available tests and markers of platelet activation did not prove successful in guiding treatment decisions for patients with cardiovascular disease, justifying further research into novel markers of platelet reactivity. Platelets contain a variety of microRNAs (miRNAs) and are a major contributor to the extracellular circulating miRNA pool. Levels of platelet-derived miRNAs in the circulation have been associated with different measures of platelet activation as well as antiplatelet therapy and have therefore been implied as potential new markers of platelet reactivity. In contrast to the ex vivo assessment of platelet reactivity by current platelet function tests, miRNA measurements may enable assessment of platelet reactivity in vivo . It remains to be seen however, whether miRNAs may aid clinical diagnostics. Major limitations in the platelet miRNA research field remain the susceptibility to preanalytical variation, non-standardized sample preparation and data normalization that hampers inter-study comparisons. In this review, we provide an overview of the literature on circulating miRNAs as biomarkers of platelet activation, highlighting the underlying biology, the application in patients with cardiovascular disease and antiplatelet therapy and elaborating on technical limitations regarding their quantification in the circulation.

Aims: Coronavirus disease 2019 (COVID-19) can lead to multiorgan damage. MicroRNAs (miRNAs) in blood reflect cell activation and tissue injury. We aimed to determine the association of circulating miRNAs with COVID-19 severity and 28 day intensive care unit (ICU) mortality., Methods and Results: We performed RNA-Seq in plasma of healthy controls (n = 11), non-severe (n = 18), and severe (n = 18) COVID-19 patients and selected 14 miRNAs according to cell- and tissue origin for measurement by reverse transcription quantitative polymerase chain reaction (RT-qPCR) in a separate cohort of mild (n = 6), moderate (n = 39), and severe (n = 16) patients. Candidates were then measured by RT-qPCR in longitudinal samples of ICU COVID-19 patients (n = 240 samples from n = 65 patients). A total of 60 miRNAs, including platelet-, endothelial-, hepatocyte-, and cardiomyocyte-derived miRNAs, were differentially expressed depending on severity, with increased miR-133a and reduced miR-122 also being associated with 28 day mortality. We leveraged mass spectrometry-based proteomics data for corresponding protein trajectories. Myocyte-derived (myomiR) miR-133a was inversely associated with neutrophil counts and positively with proteins related to neutrophil degranulation, such as myeloperoxidase. In contrast, levels of hepatocyte-derived miR-122 correlated to liver parameters and to liver-derived positive (inverse association) and negative acute phase proteins (positive association). Finally, we compared miRNAs to established markers of COVID-19 severity and outcome, i.e. SARS-CoV-2 RNAemia, age, BMI, D-dimer, and troponin. Whilst RNAemia, age and troponin were better predictors of mortality, miR-133a and miR-122 showed superior classification performance for severity. In binary and triplet combinations, miRNAs improved classification performance of established markers for severity and mortality., Conclusion: Circulating miRNAs of different tissue origin, including several known cardiometabolic biomarkers, rise with COVID-19 severity. MyomiR miR-133a and liver-derived miR-122 also relate to 28 day mortality. MiR-133a reflects inflammation-induced myocyte damage, whilst miR-122 reflects the hepatic acute phase response., (© The Author(s) 2021. Published by Oxford University Press on behalf of the European Society of Cardiology.)