β-adrenergic receptor activation promotes cardiac miR-21 expression by paracrine action of IL-6 from fibroblasts / 中国病理生理杂志

AIM:To investigate the regulation ofβ-adrenergic receptor (β-AR) agonist isoproterenol (ISO) on cardiac microRNA-21 (miR-21) expression.METHODS:The primary cultured mouse cardiomyocytes and cardiac fibroblasts were isolated by enzyme digestion and treated with ISO at 10μmol/L for 1, 6, 12, 24 and 48 h.The expression of miR-21 was detected by real-time PCR.The protein levels of p-STAT3 and STAT3 were determined by Western blot, and the concentration of interleukin-6 (IL-6) in the cultured supernatant was measured by ELISA.The cells were transfected with the luciferase reporter gene plasmid p GL3-21PPR containing the miR-21 promoter region, and the luciferase reporter gene assay was used to examine the effect of conditioned medium on the transcriptional activity of miR-21.RESULTS:The medium supernatant produced by ISO on cardiac fibroblasts was used as the conditioned medium, which increased the miR-21 expression in the cardiomyocytes in a time-dependent manner after fibroblasts was treated with ISO (P<0.05).The conditioned medium caused a significant increase in the transcriptional activity of miR-21 in the cardiomyocytes, while24 h and 48 h conditioned medium increased the transcriptional activity by 94.9％and 77.1％, respectively (P<0.01).The concentration of IL-6 in the conditioned medium was significantly increased, and the activity of transcriptional factor STAT3 was enhanced by paracrine action of IL-6 in the cardiomyocytes, which promoted the transcription and expression of miR-21.CONCLUSION:β-AR stimulation induces fibroblast synthesis and expression of IL-6 with paracrine effect on cardiomyocytes, up-regulates the expression of miR-21 in cardiomyocytes by IL-6/STAT3 pathway, and participates in the cardiac remodeling.

Excitation-Contraction Coupling Time is More Sensitive in Evaluating Cardiac Systolic Function / 中华医学杂志(英文版)

Background@#Pressure overload-induced myocardial hypertrophy is a key step leading to heart failure. Previous cellular and animal studies demonstrated that deteriorated excitation-contraction coupling occurs as early as the compensated stage of hypertrophy before the global decrease in left ventricular ejection fraction (LVEF). This study was to evaluate the cardiac electromechanical coupling time in evaluating cardiac systolic function in the early stage of heart failure.@*Methods@#Twenty-six patients with Stage B heart failure (SBHF) and 31 healthy controls (CONs) were enrolled in this study. M-mode echocardiography was performed to measure LVEF. Tissue Doppler imaging (TDI) combined with electrocardiography (ECG) was used to measure cardiac electromechanical coupling time.@*Results@#There was no significant difference in LVEF between SBHF patients and CONs (64.23 ± 8.91% vs. 64.52 ± 5.90%; P = 0.886). However, all four electromechanical coupling time courses (Qsb: onset of Q wave on ECG to beginning of S wave on TDI, Qst: onset of Q wave on ECG to top of S wave on TDI, Rsb: top of R wave on ECG to beginning of S wave on TDI, and Rst: top of R wave on ECG to top of S wave on TDI) of SBHF patients were significantly longer than those of CONs (Qsb: 119.19 ± 35.68 ms vs. 80.30 ± 14.81 ms, P < 0.001; Qst: 165.42 ± 60.93 ms vs. 129.04 ± 16.97 ms, P = 0.006; Rsb: 82.43 ± 33.66 ms vs. 48.30 ± 15.18 ms, P < 0.001; and Rst: 122.37 ± 36.66 ms vs. 93.25 ± 16.72 ms, P = 0.001), and the Qsb, Rsb, and Rst time showed a significantly higher sensitivity than LVEF (Rst: P =0.032; Rsb: P = 0.003; and Qsb: P = 0.004).@*Conclusions@#The cardiac electromechanical coupling time is more sensitive than LVEF in evaluating cardiac systolic function.

Predictive value of antiplatelet resistance on early stent thrombosis in patients with acute coronary syndrome / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Despite outstanding antiplatelet properties of aspirin and clopidogrel, some patients taking these drugs continue to suffer complications. Antiplatelet resistance appears to be a new prognostic factor in acute coronary syndrome patients for clinical events associated with stent thrombosis (ST). However, there is no optimal method to identify it and assess its correlation to clinical outcomes. This study sought to evaluate the predictive value of antiplatelet resistance assessed by whole blood impedance aggregometry for the risk of early ST in patients with acute coronary syndrome who underwent coronary stenting.</p><p><b>METHODS</b>Platelet responses to aspirin and clopidogrel in 86 patients with acute coronary syndrome were measured by whole blood impedance aggregometry. Spontaneous platelet aggregation was defined as antiplatelet resistance identified by the increased electrical impedance. The clinical endpoint was early stent thrombosis during 30-day follow-up after coronary stenting.</p><p><b>RESULTS</b>The prevalence of aspirin resistance, clopidogrel resistance and dual resistance of combined clopidogrel and aspirin resistance were 19.8%, 12.8% and 5.8% respectively. Diabetes, female and higher platelet counts were more frequently detected in clopidogrel-resistant and dual-resistant patients. During 30-day follow-up, the patients with clopidogrel resistance and dual resistance had higher incidence of early stent thrombosis (18.2% vs. 1.3%, 40.0% vs. 1.2%, P < 0.05). Binary Logistic Regression analysis indicated that dual resistance remained an independent predicator for early stent thrombosis (odds ratio 34.064, 95%CI 1.919 - 604.656, P = 0.016).</p><p><b>CONCLUSIONS</b>Antiplatelet resistance assessed by whole blood impedance aggregometry is paralleled to clinical events, and dual antiplatelet resistance is an independent predicator for early stent thrombosis in patients with acute coronary syndrome. As a physiological assessment of platelet reactivity, whole blood impedance aggregometry is a convenient and accurate option for measuring antiplatelet resistance and hence predicting early stent thrombosis.</p>

Prevalence and related factors of prostatitis-like symptoms in young men / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate the prevalence and related factors of prostatitis-like symptoms among young men.</p><p><b>METHODS</b>The study was a cross-sectional survey of 2500 young men aged 18-30 years in the city of Weifang, and all of them completed a questionnaire on prostatitis. The univariate and multivariate logistic regression procedures were used to investigate the risk factors among the young men with chronic prostatitis-like symptoms.</p><p><b>RESULTS</b>The valid response rate was 85% (n = 2125). Of the 128 subjects (6.02%) identified as having chronic prostatitis-like symptoms, the mean age was 21.8 years, the average pain score was 6.98 +/- 0.29, and the average voiding score was 3.77 +/- 0.25. Of the sampled population, 39 men had prostatitis-like symptoms with an index pain score of 8 or more. Significant risk factors include frequent masturbation, prolonged sitting, long-time fixed posture, cold environment, stress at home and work.</p><p><b>CONCLUSION</b>The study suggested that chronic prostatitis-like symptoms are common among young men, and the urethritis history, frequent masturbation, prolonged sitting, long-time urine holding, cold environment, and stress at home and work might be significant risk factors.</p>