Gene associations of lipid traits, lipid-lowering drug-target genes and endometriosis.

RESEARCH QUESTION: Does the observed correlation between dyslipidaemia and endometriosis indicate a bidirectional causal association? DESIGN: Bidirectional Mendelian randomization was used to investigate the causal association between lipid traits and endometriosis. Drug-target Mendelian randomization was used to explore potential drug-target genes for managing endometriosis. In cases where lipid-mediated effects via specific drug targets were significant, aggregate analyses, such as summary-data-based Mendelian randomization and colocalization methods, were introduced to validate the outcomes. Mediation analyses supplemented these evaluations. RESULTS: The bidirectional Mendelian randomization results suggested that genetically predicted triglyceride (OR 1.15, 95% CI 1.08-1.23), high-density lipoprotein cholesterol (OR 0.87, 95% CI 0.81-0.94), low-density lipoprotein cholesterol (OR 1.20, 95% CI 1.06-1.34) and apolipoprotein A (OR 0.90, 95% CI 0.83-0.96) concentrations were causally associated with endometriosis. Reverse Mendelian randomization results revealed that genetically proxied endometriosis was causally associated with triglyceride concentration (OR 1.02, 95% CI 1.01-1.02). In drug-target Mendelian randomization, genetic mimicry in proprotein convertase subtilisin/kexin type 9 (PCSK9) (OR 1.40, 95% CI 1.13-1.72), apolipoprotein B (APOB) (OR 1.49, 95% CI 1.21-1.86) and angiopoietin-related protein 3 (ANGPTL3) (OR 1.57, 95% CI 1.14-2.16) was significantly associated with the risk of endometriosis stages 1-2. CONCLUSION: There is a potential bidirectional causal association between endometriosis and dyslipidaemia. Genetic mimicry of PCSK9, APOB and ANGPTL3 is associated with the risk of early-stage endometriosis. The development of lipid-lowering drugs to treat endometriosis is of potential clinical interest.

PPARD rs2016520 polymorphism affects repaglinide response in Chinese Han patients with type 2 diabetes mellitus.

Repaglinide is a short-acting insulin secretagogue, which often results in considerable interindividual variability in therapeutic efficacy when widely used in a clinical setting. Among various reasons under discussion is genetic polymorphism, especially the genes related to insulin secretion and resistance. Recent studies have described the importance of PPARD in regulating the secretion and resistance of insulin. However, little is known about the impacts of PPARD genetic polymorphism on the efficacy of repaglinide. Therefore, the current study was designed to investigate the associations of PPARD rs2016520 polymorphism with type 2 diabetes mellitus (T2DM) susceptibility and repaglinide therapeutic efficacy in Chinese Han T2DM patients. A total of 338 T2DM patients and 200 healthy subjects were genotyped for PPARD rs2016520 polymorphism by polymerase chain reaction-restriction fragment length polymorphism assay. A total of 84 patients with the same genotypes of CYP2C8*3 139Arg and OATP1B1 521TT were randomized to orally take repaglinide for 8 weeks. Then the pharmacodynamic parameters of repaglinide and biochemical indicators were determined before and after repaglinide treatment. No significant difference was found in either allelic frequency (P = 0.298) or genotype distribution (P = 0.151) of PPARD rs2016520 between T2DM patients and healthy subjects. However, T2DM patients carrying genotype TC showed a significantly lower increase in postprandial serum insulin (mU/L) than those with wild-type TT (P < 0.05). These findings suggest that PPARD rs2016520 polymorphism might influence the therapeutic effect of repaglinide rather than T2DM susceptibility in Chinese Han T2DM patients.

Study on Springback Straightening after Bending of the U-Section of TC4 Material under High-Temperature Conditions.

The thin-walled structures of titanium alloys have peculiar characteristics involving thin curved surfaces, complicated structures, and a poor rigidity. Therefore, bending or twisting distortion frequently occurs in forging, extrusion, drawing, transportation, cooling, and manufacturing. Straightening theory focuses on the straightening curvature or bending moment at room temperature, and a unified analytical model of the straightening curvature, the straightening bending moment, and the straightening stroke, as well as a study on springback straightening under high-temperature conditions, have not been investigated comprehensively. In order to understand the inherent mechanism of springback straightening and quantitative prediction of springback under high-temperature conditions, uniaxial tension tests were carried out to obtain the true stress-strain model of material and stress relaxation under the stress relaxation model. This paper is based on the theory of elastic-plastic mechanics and combines this with the mechanism of stress relaxation to establish springback and residual relative curvature equations of springback. The law of springback straightening is further explored, and springback and residual deflection equations are provided. The results of the study showed that the relative errors of the theoretical residual deflection of the bending deformation and residual deflections obtained by the experiment were less than 20%, with an average absolute error of less than 10%. Therefore, the hardening models adopted can achieve an allowable relative error if hardening parameters are properly selected. The proposed research provides basic data for the prediction of springback straightening, and the design of springback compensation tools can be applied in practical applications.