98 research outputs found

    Cardiac Myosin Binding Protein C and MAP-Kinase Activating Death Domain-Containing Gene Polymorphisms and Diastolic Heart Failure

    Get PDF
    OBJECTIVE: Myosin binding protein C (MYBPC3) plays a role in ventricular relaxation. The aim of the study was to investigate the association between cardiac myosin binding protein C (MYBPC3) gene polymorphisms and diastolic heart failure (DHF) in a human case-control study. METHODS: A total of 352 participants of 1752 consecutive patients from the National Taiwan University Hospital and its affiliated hospital were enrolled. 176 patients diagnosed with DHF confirmed by echocardiography were recruited. Controls were matched 1-to-1 by age, sex, hypertension, diabetes, renal function and medication use. We genotyped 12 single nucleotide polymorphisms (SNPs) according to HapMap Han Chinese Beijing databank across a 40 kb genetic region containing the MYBPC3 gene and the neighboring DNA sequences to capture 100% of haplotype variance in all SNPs with minor allele frequencies ≥ 5%. We also analyzed associations of these tagging SNPs and haplotypes with DHF and linkage disequilibrium (LD) structure of the MYBPC3 gene. RESULTS: In a single locus analysis, SNP rs2290149 was associated with DHF (allele-specific p = 0.004; permuted p = 0.031). The SNP with a minor allele frequency of 9.4%, had an odds ratio 2.14 (95% CI 1.25-3.66; p = 0.004) for the additive model and 2.06 for the autosomal dominant model (GG+GA : AA, 95% CI 1.17-3.63; p = 0.013), corresponding to a population attributable risk fraction of 12.02%. The haplotypes in a LD block of rs2290149 (C-C-G-C) was also significantly associated with DHF (odds ratio 2.10 (1.53-2.89); permuted p = 0.029). CONCLUSIONS: We identified a SNP (rs2290149) among the tagging SNP set that was significantly associated with early DHF in a Chinese population

    Evolutionarily Divergent, Unstable Filamentous Actin Is Essential for Gliding Motility in Apicomplexan Parasites

    Get PDF
    Apicomplexan parasites rely on a novel form of actin-based motility called gliding, which depends on parasite actin polymerization, to migrate through their hosts and invade cells. However, parasite actins are divergent both in sequence and function and only form short, unstable filaments in contrast to the stability of conventional actin filaments. The molecular basis for parasite actin filament instability and its relationship to gliding motility remain unresolved. We demonstrate that recombinant Toxoplasma (TgACTI) and Plasmodium (PfACTI and PfACTII) actins polymerized into very short filaments in vitro but were induced to form long, stable filaments by addition of equimolar levels of phalloidin. Parasite actins contain a conserved phalloidin-binding site as determined by molecular modeling and computational docking, yet vary in several residues that are predicted to impact filament stability. In particular, two residues were identified that form intermolecular contacts between different protomers in conventional actin filaments and these residues showed non-conservative differences in apicomplexan parasites. Substitution of divergent residues found in TgACTI with those from mammalian actin resulted in formation of longer, more stable filaments in vitro. Expression of these stabilized actins in T. gondii increased sensitivity to the actin-stabilizing compound jasplakinolide and disrupted normal gliding motility in the absence of treatment. These results identify the molecular basis for short, dynamic filaments in apicomplexan parasites and demonstrate that inherent instability of parasite actin filaments is a critical adaptation for gliding motility

    Genetic Drivers of Heterogeneity in Type 2 Diabetes Pathophysiology

    Get PDF
    Type 2 diabetes (T2D) is a heterogeneous disease that develops through diverse pathophysiological processes1,2 and molecular mechanisms that are often specific to cell type3,4. Here, to characterize the genetic contribution to these processes across ancestry groups, we aggregate genome-wide association study data from 2,535,601 individuals (39.7% not of European ancestry), including 428,452 cases of T2D. We identify 1,289 independent association signals at genome-wide significance (P \u3c 5 × 10-8) that map to 611 loci, of which 145 loci are, to our knowledge, previously unreported. We define eight non-overlapping clusters of T2D signals that are characterized by distinct profiles of cardiometabolic trait associations. These clusters are differentially enriched for cell-type-specific regions of open chromatin, including pancreatic islets, adipocytes, endothelial cells and enteroendocrine cells. We build cluster-specific partitioned polygenic scores5 in a further 279,552 individuals of diverse ancestry, including 30,288 cases of T2D, and test their association with T2D-related vascular outcomes. Cluster-specific partitioned polygenic scores are associated with coronary artery disease, peripheral artery disease and end-stage diabetic nephropathy across ancestry groups, highlighting the importance of obesity-related processes in the development of vascular outcomes. Our findings show the value of integrating multi-ancestry genome-wide association study data with single-cell epigenomics to disentangle the aetiological heterogeneity that drives the development and progression of T2D. This might offer a route to optimize global access to genetically informed diabetes care

    Genetic drivers of heterogeneity in type 2 diabetes pathophysiology

    Get PDF
    Type 2 diabetes (T2D) is a heterogeneous disease that develops through diverse pathophysiological processes1,2 and molecular mechanisms that are often specific to cell type3,4. Here, to characterize the genetic contribution to these processes across ancestry groups, we aggregate genome-wide association study data from 2,535,601 individuals (39.7% not of European ancestry), including 428,452 cases of T2D. We identify 1,289 independent association signals at genome-wide significance (P &lt; 5 × 10-8) that map to 611 loci, of which 145 loci are, to our knowledge, previously unreported. We define eight non-overlapping clusters of T2D signals that are characterized by distinct profiles of cardiometabolic trait associations. These clusters are differentially enriched for cell-type-specific regions of open chromatin, including pancreatic islets, adipocytes, endothelial cells and enteroendocrine cells. We build cluster-specific partitioned polygenic scores5 in a further 279,552 individuals of diverse ancestry, including 30,288 cases of T2D, and test their association with T2D-related vascular outcomes. Cluster-specific partitioned polygenic scores are associated with coronary artery disease, peripheral artery disease and end-stage diabetic nephropathy across ancestry groups, highlighting the importance of obesity-related processes in the development of vascular outcomes. Our findings show the value of integrating multi-ancestry genome-wide association study data with single-cell epigenomics to disentangle the aetiological heterogeneity that drives the development and progression of T2D. This might offer a route to optimize global access to genetically informed diabetes care.</p

    The Effect of Inclined Crack Tip Shapes on the Stress Fields in Flat Plates

    No full text

    A fast method of surgical tracheostomy: A preliminary result of minimally invasive tracheostomy

    No full text
    Introduction: Currently, the percutaneous puncture method is a popular method for performing tracheostomies. However, unexpected bleeding or organ injury is a concern with this method because the dissection or dilatation is blind. A con- ventional open surgical tracheostomy (COST) usually takes more time to complete, but the procedure has a lower risk of bleeding compared to blind method used in the percutaneous puncture approach. In this study, we evaluated a fast open surgical tracheostomy (FOST) procedure, which combines the advantages of both open and percutaneous methods. Materials and Methods: From January 1, 2009, to December 31, 2010, our team performed surgeries on 259 patients in our institution that were indicated for tracheostomy. During this period, both COST and FOST methods were performed. These patients were not randomized with regard to method. No additional or specialized tools are required in the FOST method. All operations were performed by a single surgeon. The operative details and outcomes were analyzed. Results: One hundred and fifty-six patients underwent COST, while 103 patients underwent FOST. There was no differ- ence in gender distribution, age and indications for surgery in either group. The operative time was much faster in FOST than in COST. There was no acute or delayed bleeding in either group. Minor stoma infection was seen in five patients in the FOST group and 12 patients in the COST group. Conclusion: The FOST provided a faster alternative to COST, while preserving the techniques of open dissection and resulting in comparable outcomes. [Arch Clin Exp Surg 2015; 4(1.000): 36-40

    Soluble ICAM-1, Independent of IL-6, Is Associated with Prevalent Frailty in Community-Dwelling Elderly Taiwanese People.

    No full text
    BACKGROUND:Activation of inflammatory pathway with elevation of inflammatory biomarkers such as Interleukin 6 (IL-6) has been considered a pathophysiological feature of frailty. In recent years, the association between Intercellular adhesive molecule -1 (ICAM-1) and vascular inflammatory was established. Provocation of inflammatory cascades from ICAM-1 is potential IL-6 related, although the association between the inflammatory process and frailty is little to known. The study was intended to evaluate the relationship between serum ICAM-1, IL-6 and frailty. MATERIALS AND METHODS:Data was derived from a representative national sampling cohort in Taiwan. The cross-sectional study included nine-hundred-forty-six community-dwelling people aged 53 and older. Frailty was defined as having three or more components (including, muscle shrinkage, slowness, weakness, exhaustion, and low activity) Serum IL-6 and ICAM-1 levels were measured using standard enzyme-linked immunosorbent assays. RESULTS:Soluble ICAM-1 (sICAM-1) levels were stepwise increased in non-frail, pre-frail and frail elderly people (the median levels were 255 vs. 265 vs. 285 ng/ml, respectively p<0.001). A multivariate multinomial logistic regression, which was adjusted for age, sex, smoking, education, BMI, and chronic disease number, was utilized to determine that the probability of being frail due to increased log (ICAM-1) and log (IL-6) standard deviation levels were 1.44 (95% CI 1.09-1.91) and 1.54 (95%CI 1.07-2.20), respectively. CONCLUSION:sICAM-1 was significantly associated with frailty, independent of IL-6. This implied that leukocyte migration and inflammation cascade activation might contribute to frailty, in addition to monocyte/macrophage-mediated immuno-inflammation
    corecore