Background: Biological pacemakers derived from pluripotent stem cell (PSC) have been considered as a potential therapeutic surrogate for sick sinus syndrome. So it is essential to develop highly efficient strategies for enrichment of sinoatrial node-like cells (SANLCs) as seed cells for biological pacemakers. It has been reported that BMP, FGF, and RA signaling pathways are involved in specification of different cardiomyocyte subtypes, pacemaker, ventricular, and atrial cells. We aimed to investigate whether combined modulation of BMP, FGF, and RA signaling pathways could enrich the differentiation of SANLC from human pluripotent stem cell (hiPSC). Methods: During the differentiation process from human induced pluripotent stem cell to cardiomyocyte through small molecule-based temporal modulation of the Wnt signaling pathway, signaling of BMP, FGF, and RA was manipulated at cardiac mesoderm stage. qRT-PCR, immunofluorescence, flow cytometry, and whole cell patch clamp were used to identify the SANLC.

AIMTo explore the natural history of covert hepatic encephalopathy (CHE) in absence of medication intervention.METHODSConsecutive outpatient cirrhotic patients in a Chinese tertiary care hospital were enrolled and evaluated for CHE diagnosis. They were followed up for a mean of 11.2 ± 1.3 mo. Time to the first cirrhosis-related complications requiring hospitalization, including overt HE (OHE), resolution of CHE and death/transplantation, were compared between CHE and no-CHE patients. Predictors for complication(s) and death/transplantation were also analyzed.RESULTSA total of 366 patients (age: 47.2 ± 8.6 years, male: 73.0%) were enrolled. CHE was identified in 131 patients (35.8%). CHE patients had higher rates of death and incidence of complications requiring hospitalization, including OHE, compared to unimpaired patients. Moreover, 17.6% of CHE patients developed OHE, 42.0% suffered persistent CHE, and 19.8% of CHE spontaneously resolved. In CHE patients, serum albumin < 30 g/L (HR = 5.22, P = 0.03) was the sole predictor for developing OHE, and blood creatinine > 133 μmol/L (HR = 4.75, P = 0.036) predicted mortality. Child-Pugh B/C (HR = 0.084, P < 0.001) and OHE history (HR = 0.15, P = 0.014) were predictors of spontaneous resolution of CHE.CONCLUSIONCHE exacerbates, persists or resolves without medication intervention in clinically stable cirrhosis. Triage of patients based on these predictors will allow for more cost-effect management of CHE.

The surged systemic vascular inflammation after acute myocardial infarction (AMI) aggravates the atherosclerotic endothelial injury. To explore roles of miR‐499 released from cardiomyocytes during AMI in endothelial injury. Using qPCR and ELISA, we discovered that patients with AMI had significantly increased plasma miR‐499, which was directly correlated with serum thrombomodulin, a marker for endothelial injury. Plasma of AMI patients, when incubated with human umbilical vein endothelial cells (HUVECs), significantly increased the expression of endothelial injury markers, which could be abrogated by antagomiR‐499. In vitro, neonatal rat cardiomyocytes subjected to hypoxia/reoxygenation (HX/R) released miR‐499 that could be internalized into rat pulmonary microvascular endothelial cells (RPMECs), worsening the high glucose‐induced injury. In silico analysis demonstrated that CHRNA7 encoding α7‐nAchR is a target of miR‐499, which was validated in cell lines expressing endogenous α7‐nAchR. In high glucose‐induced RPMECs injury model, miR‐499 aggravated, whereas forced CHRNA7 expression ameliorated the injury. Moreover, the perfusate from Langendorff perfused rat heart subjected to HX/R contained higher level of miR‐499 that significantly impaired the Bradykinin‐mediated endothelium‐dependent relaxation in both conduit and resistance arteries, which could be partially abrogated by antagomiR‐499. Finally, the correlation between plasma miR‐499 and endothelial injury was further confirmed in another cohort of AMI patients. We conclude that miR‐499 released from injured cardiomyocytes contributes to the endothelial injury by targeting α7‐nAchR. This study implies that miR‐499 may serve as a potential target for the treatment of the surged vascular inflammation post‐AMI.

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ObjectiveTo investigate the relationship between sex hormones and the risk of vascular disease in elderly men and to evaluate the advantages and disadvantages of testosterone replacement.MethodsA total of 337 men, aged 60 to 91 years, were enrolled in this single-center, cross-sectional study, and their sex hormone levels were assessed. Linear and logistic regression analyses were utilized to compare the sex hormone levels between patients with and without vascular disease. The nonparametric K-sample test was used for inter-group comparisons.ResultsAging and abnormal metabolism were both significantly associated with an increased risk of vascular diseases and changes in sex hormone levels. Primary linear and logistic regression analyses showed no significant differences in sex hormone concentrations between patients with and without vascular diseases after adjusting for age. Logistic regression with abnormal metabolism as categorical variable showed that free testosterone (FT) and free estradiol (FE2) had significant relationships with CEVD risk (P<0.05). In further regression with all metabolic continuous variables included, the testosterone/estradiol (T/E2) ratio replaced FT and FE2 (P<0.05). Trend line analyses showed that T/E2 actually had a binomial linear correlation with the risk of cerebrovascular disease; its best protective effect occurred at values of 0.13–0.15, with an OR value extremely close to those of FT and FE2 (0.23 vs. 0.24–0.25).ConclusionT/E2 balance plays a key role in the relationship between sex hormones and the risk of cerebrovascular disease. The balance between T and E2 may be more important than their absolute quantities. Extremely low T/E2 and inappropriately high T/E2 ratio can both harm the brain blood vessels. Careful consideration should be given before beginning testosterone replacement treatment, and supplementing with estrogen seems to be a good way to protect blood vessels of the brain in elderly men.