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Biology subjects

Tsao, P.

Publications and source records attributed to Tsao, P..

4 recordsLinked to original sources

Platelets are Protective in Early Abdominal Aortic Aneurysm Formation

BackgroundAbdominal aortic aneurysm (AAA) is a disease associated with the pathophysiologic degradation of the tunica media resulting in aortic dilatation, systemic inflammation, and dysregulated hemostasis. Beyond role its role in initiating primary hemostasis, platelets are a source of ROS, inflammatory cytokines and growth factors necessary for angiogenesis and vascular remodeling. Although platelets contribute to the progression of established aneurysms, their role in the initiation of AAA remains undefined. MethodsLow density lipoprotein receptor deficient (Ldlr-/-) mice were examined for platelet accumulation in the angiotensin II (AngII) model of AAA utilizing in vivo labeling techniques. Two platelet antagonists (clopidogrel and aspirin), a thrombin inhibitor (dabigatran) or genetic deficiencies (protease-activated receptor 4, P2Y12, Lnk) were administered to AngII-infused mice to determine the role of platelets in initiation of AAA. The effect of platelet depletion was examined in multiple mouse strains of AngII-induced AAA and two additional aneurysm models. PheWAS and meta-analysis was analyzed in humans for platelet gene SNPs associated with AAA. ResultsWe show that platelets are recruited rapidly to the aorta after the initiation of AngII infusion. Genetic deficiency of platelet receptors had no effect on abdominal aortic diameter, but augmented rupture-induced death in littermate versus placebo controls during AngII-induced AAA. Moreover, Ldlr-/- mice receiving anti-platelet inhibitors or a thrombin inhibitor also had augmented rupture-induced death. Platelet depletion preceding aneurysm formation resulted in pervasive rupture-induced death in several mouse strains and with three different mouse models of AAA. ConclusionsInhibition of platelet function is detrimental in an early expanding aortic lumen resulting in catastrophic rupture and hemodynamic failure in murine AAA models.

pathology↗

Deconvolution of polygenic risk score in single cells unravels cellular and molecular heterogeneity of complex human diseases

Polygenic risk scores (PRSs) are commonly used for predicting an individuals genetic risk of complex diseases. Yet, their implication for disease pathogenesis remains largely limited. Here, we introduce scPRS, a geometric deep learning model that constructs single-cell-resolved PRS leveraging reference single-cell chromatin accessibility profiling data to enhance biological discovery as well as disease prediction. Real-world applications across multiple complex diseases, including type 2 diabetes (T2D), hypertrophic cardiomyopathy (HCM), and Alzheimers disease (AD), showcase the superior prediction power of scPRS compared to traditional PRS methods. Importantly, scPRS not only predicts disease risk but also uncovers disease-relevant cells, such as hormone-high alpha and beta cells for T2D, cardiomyocytes and pericytes for HCM, and astrocytes, microglia and oligodendrocyte progenitor cells for AD. Facilitated by a layered multi-omic analysis, scPRS further identifies cell-type-specific genetic underpinnings, linking disease-associated genetic variants to gene regulation within corresponding cell types. We substantiate the disease relevance of scPRS-prioritized HCM genes and demonstrate that the suppression of these genes in HCM cardiomyocytes is rescued by Mavacamten treatment. Additionally, we establish a novel microglia-specific regulatory relationship between the AD risk variant rs7922621 and its target genes ANXA11 and TSPAN14. We further illustrate the detrimental effects of suppressing these two genes on microglia phagocytosis. Our work provides a multi-tasking, interpretable framework for precise disease prediction and systematic investigation of the genetic, cellular, and molecular basis of complex diseases, laying the methodological foundation for single-cell genetics.

genetics↗

Pharmacogenetic allele variant frequencies: An analysis of the VAs Million Veteran Program (MVP) as a representation of the diversity in US population.

We present allele frequencies of pharmacogenomics relevant variants across multiple ancestry in a sample representative of the US population. We analyzed 658,582 individuals with genotype data and extracted pharmacogenomics relevant single nucleotide variant (SNV) alleles, human leukocyte antigens (HLA) 4-digit alleles and an important copy number variant (CNV), the full deletion/duplication of CYP2D6. We compiled distinct allele frequency tables for European, African American, Hispanic, and Asian ancestry individuals. In addition, we compiled allele frequencies based on local ancestry reconstruction in the African-American (2-way deconvolution) and Hispanic (3-way deconvolution) cohorts.

genomics↗

T32 training is associated with increased likelihood of obtaining an academic research faculty position: a cross-sectional study

BackgroundThe main mission of NIH-sponsored institutional training programs such as the T32 is to provide strong research and career training for early career scientists, while preparing those individuals to become leaders working to meet the health-related research needs of the nation. One of the main avenues to pursue health-related research is becoming research faculty at an academic institution. It is therefore important to know whether these programs are succeeding in this mission, or, if barriers exist that prevent trainees from pursuing these careers. MethodsOur institution currently trains ~ 2400 post-doctoral scholars per year, approximately 5% of whom are enrolled in one of our 33 T32 programs. In this study, we 1) compare the professional outcomes of T32 trainees with non-T32 trainees at our institution, and 2) survey past and current T32 trainees in a subset of high-performing cardiovascular programs about the barriers and enablers they experienced to pursuing research-oriented careers. ResultsFormer T32 trainees are significantly more likely to attain appointments as primarily research faculty members, compared to other trainees. Trainees report a perceived lack of stability, the paucity of open positions, and the publish or perish competitive mentality of academia as their top reasons for abandoning careers in academia. However, they were still more likely to choose research over clinical careers after participating in a dedicated T32 program. ConclusionsOur results support the conclusion that structured training programs strengthen the pipeline of young scientists pursuing careers in academic research, including those from underrepresented backgrounds. However, T32 postdoctoral researchers are held back from pursuing academic careers by a perceived lack of stability and high competition for faculty positions. FundingThis research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

scientific communication and education↗