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21.
Myocarditis in response to COVID-19 vaccination has been reported since early 2021. In particular, young male individuals have been identified to exhibit an increased risk of myocardial inflammation following the administration of mRNA-based vaccines. Even though the first epidemiological analyses and numerous case reports investigated potential relationships, endomyocardial biopsy (EMB)-proven cases are limited. Here, we present a comprehensive histopathological analysis of EMBs from 15 patients with reduced ejection fraction (LVEF = 30 (14–39)%) and the clinical suspicion of myocarditis following vaccination with Comirnaty® (Pfizer-BioNTech) (n = 11), Vaxzevria® (AstraZenica) (n = 2) and Janssen® (Johnson & Johnson) (n = 2). Immunohistochemical EMB analyses reveal myocardial inflammation in 14 of 15 patients, with the histopathological diagnosis of active myocarditis according the Dallas criteria (n = 2), severe giant cell myocarditis (n = 2) and inflammatory cardiomyopathy (n = 10). Importantly, infectious causes have been excluded in all patients. The SARS-CoV-2 spike protein has been detected sparsely on cardiomyocytes of nine patients, and differential analysis of inflammatory markers such as CD4+ and CD8+ T cells suggests that the inflammatory response triggered by the vaccine may be of autoimmunological origin. Although a definitive causal relationship between COVID-19 vaccination and the occurrence of myocardial inflammation cannot be demonstrated in this study, data suggest a temporal connection. The expression of SARS-CoV-2 spike protein within the heart and the dominance of CD4+ lymphocytic infiltrates indicate an autoimmunological response to the vaccination.  相似文献   
22.
Multimedia Tools and Applications - We describe the “Multimodal Person Discovery in Broadcast TV” task of MediaEval 2015 benchmarking initiative. Participants were asked to return the...  相似文献   
23.
水化水泥颗粒表面超塑化剂吸附层分布模型   总被引:1,自引:0,他引:1  
制备了钙矾石(AFt)、单硫型硫铝酸钙(AFm)和钾长石类单矿物,并研究了三聚氰胺磺酸盐甲醛缩聚物(PMS)、β-萘磺酸盐甲醛缩合物(BNS)及聚羧酸盐(PC)等几种化学成分不同的超塑化剂在其早期水化颗粒表面上的吸附行为.研究发现,zeta电位是决定水泥颗粒表面对超塑化剂吸附量的关键因素.以溶液沉淀析出法人工合成的AFt具有较高的正zeta电位,能吸附大量带负电荷的超塑化剂,AFm仅带少量正电荷,其吸附超塑化剂相对较少,钾长石、氢氧钙石和石膏的zeta电位几乎为零或负值,因而基本不吸附超塑化剂.根据实验结果,笔者认为水化水泥颗粒用马赛克结构表示为最佳,而超塑化剂主要吸附在AF表面上.  相似文献   
24.
Most anti-cancer drug screening assays are currently performed in two dimensions, on flat, rigid surfaces. However, there are increasing indications that three-dimensional (3D) platforms provide a more realistic setting to investigate accurate morphology, growth, and sensitivity of tumor cells to chemical factors. Moreover, interstitial flow plays a pivotal role in tumor growth. Here, we present a microfluidic 3D platform to investigate behaviors of tumor cells in flow conditions with anti-migratory compounds. Our results show that interstitial flow and its direction have significant impact on migration and growth of hepatocellular carcinoma cell lines such as HepG2 and HLE. In particular, HepG2/HLE cells tend to migrate against interstitial flow, and their growth increases in interstitial flow conditions regardless of the flow direction. Furthermore, this migratory activity of HepG2 cells is enhanced when they are co-cultured with human umbilical vein endothelial cells. We also found that migration activity of HepG2 cells attenuates under hypoxic conditions. In addition, the effect of Artemisinin, an anti-migratory compound, on HepG2 cells was quantitatively analyzed. The microfluidic 3D platform described here is useful to investigate more accurately the effect of anti-migratory drugs on tumor cells and the critical influence of interstitial flow than 2D culture models.  相似文献   
25.
26.
Hospitals traditionally segregate resources into centralized functional departments such as diagnostic departments, ambulatory care centers, and nursing wards. In recent years this organizational model has been challenged by the idea that higher quality of care and efficiency in service delivery can be achieved when services are organized around patient groups. Examples include specialized clinics for breast cancer patients and clinical pathways for diabetes patients. Hospitals are struggling with the question of whether to become more centralized to achieve economies of scale or more decentralized to achieve economies of focus. In this paper we examine service and patient group characteristics to study the conditions where a centralized model is more efficient, and conversely, where a decentralized model is more efficient. This relationship is examined analytically with a queuing model to determine the most influential factors and then with simulation to fine-tune the results. The tradeoffs between economies of scale and economies of focus measured by these models are used to derive general management guidelines.  相似文献   
27.
28.
The accuracy of genomic prediction determines response to selection. It has been hypothesized that accuracy of genomic breeding values can be increased by a higher density of variants. We used imputed whole-genome sequence data and various single nucleotide polymorphism (SNP) selection criteria to estimate genomic breeding values in Brown Swiss cattle. The extreme scenarios were 50K SNP chip data and whole-genome sequence data with intermediate scenarios using linkage disequilibrium-pruned whole-genome sequence variants, only variants predicted to be missense, or the top 50K variants from genome-wide association studies. We estimated genomic breeding values for 3 traits (somatic cell score, nonreturn rate in heifers, and stature) and found differences in accuracy levels between traits. However, among different SNP sets, accuracy was very similar. In our analyses, sequence data led to a marginal increase in accuracy for 1 trait and was lower than 50K for the other traits. We concluded that the inclusion of imputed whole-genome sequence data does not lead to increased accuracy of genomic prediction with the methods.  相似文献   
29.
Coenzyme A (CoA) thioesters are formed during anabolic and catabolic reactions in every organism. Degradation pathways of growth-supporting substrates in bacteria can be predicted by differential proteogenomic studies. Direct detection of proposed metabolites such as CoA thioesters by high-performance liquid chromatography coupled with high-resolution mass spectrometry can confirm the reaction sequence and demonstrate the activity of these degradation pathways. In the metabolomes of the anaerobic sulfate-reducing bacterium Desulfobacula toluolica Tol2T grown with different substrates various CoA thioesters, derived from amino acid, fatty acid or alcohol metabolism, have been detected. Additionally, the cell extracts of this bacterium revealed a number of CoA analogues with molecular masses increased by 1 dalton. By comparing the chromatographic and mass spectrometric properties of synthetic reference standards with those of compounds detected in cell extracts of D. toluolica Tol2T and by performing co-injection experiments, these analogues were identified as inosino-CoAs. These CoA thioesters contain inosine instead of adenosine as the nucleoside. To the best of our knowledge, this finding represents the first detection of naturally occurring inosino-CoA analogues.  相似文献   
30.
Thin films composed of ZnO nanowires (NWs) hierarchically organized with an urchin-like 3D morphology were obtained by combining the electrochemical deposition and sphere lithography methods. Deposited on a transparent conductive oxide substrate (TCO), a monolayer of carboxylate modified polystyrene spheres organized with a hexagonal closed-packed structure played the role of a template. The spheres were activated in a solution of zinc chloride by the formation of bonds between the carboxylate terminals and the Zn2+ ions and were used as a template for the electrodeposition of vertically aligned ZnO NWs around them. Without this treatment, ZnO NWs were deposited only on the TCO substrate between the PS spheres. To reach a density of nanowires high enough to obtain the urchin morphology, the concentration of ZnCl2 had to be at least equal to 2 M. It was also found, as soon as small grains of ZnO started to be electrodeposited on the polystyrene spheres that the spheres were no longer close packed. The space created between them increased with the increase in the number of small ZnO grains and the increase in their length, allowing the further growth of the nanowires between the spheres. As a result the initial round shape of the spheres was modified and the urchin-like ZnO exhibited an ellipsoidal shape.  相似文献   
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