Arsenite induces premature senescence via p53/p21 pathway as a result of DNA damage in human malignant glioblastoma cells

In this study, we investigate whether arsenite-induced DNA damage leads to p53-dependent premature senescence using human glioblastoma cells with p53-wild type (U87MG-neo) and p53 deficient (U87MG-E6). A dose dependent relationship between arsenite and reduced cell growth is demonstrated, as well as induced γH2AX foci formation in both U87MG-neo and U87MG-E6 cells at low concentrations of arsenite. Senescence was induced by arsenite with senescence-associated β-galactosidase staining. Dimethyl- and trimethyl-lysine 9 of histone H3 (H3DMK9 and H3TMK9) foci formation was accompanied by p21 accumulation only in U87MG-neo but not in U87MG-E6 cells. This suggests that arsenite induces premature senescence as a result of DNA damage with heterochromatin forming through a p53/p21 dependent pathway. p21 and p53 siRNA consistently decreased H3TMK9 foci formation in U87M G-neo but not in U87MG-E6 cells after arsenite treatment. Taken together, arsenite reduces cell growth independently of p53 and induces premature senescence via p53/p21-dependent pathway following DNA damage. [BMB Reports 2014; 47(10): 575-580]     

先兆早产、胎膜早破、妊娠期糖尿病及正常妊娠女性阴道菌群分布的比较

目的:比较先兆早产、胎膜早破、妊娠期糖尿病及正常妊娠女性阴道菌群分布情况。方法:选择2016年6月至2018年6月在苏州大学附属第二医院妇产科住院的妊娠女性806例,其中先兆早产组206例,胎膜早破组234例,妊娠期糖尿病组156例,正常妊娠组210例。记录四组女性异常阴道菌群检出率及异常阴道菌群分布情况。结果:四组女性的年龄、孕周比较无统计学差异(P>0.05)。先兆早产组、胎膜早破组异常阴道菌群检出率高于妊娠期糖尿病组、正常妊娠组(P<0.05),而妊娠期糖尿病组、正常妊娠组异常阴道菌群检出率比较无统计学差异(P>0.05)。先兆早产组、妊娠期糖尿病组白色假丝酵母菌检出率高于胎膜早破组、正常妊娠组(P<0.05),先兆早产组、胎膜早破组阴道加德纳菌检出率高于妊娠期糖尿病组、正常妊娠组(P<0.05),先兆早产组无乳链球菌检出率高于胎膜早破组、妊娠期糖尿病组、正常妊娠组(P<0.05),胎膜早破组大肠埃希菌检出率高于先兆早产组、妊娠期糖尿病组、正常妊娠组(P<0.05)。结论:妊娠女性阴道感染以白色假丝酵母菌、大肠埃希菌、无乳链球菌、阴道加德纳菌为主,且先兆早产、胎膜早破女性阴道致病菌感染率较高,妊娠期糖尿病女性阴道白色假丝酵母菌的感染率较高。     

Investigating a method for pharmacologic semen collection in alpacas

While semen evaluation is standard practice prior to a sale or when infertility is suspected in other species, it is rarely done in camelids due to the difficulties involved in collecting a sample. The reproductive physiology of alpacas differs to that of other domestic animals and is still poorly understood. In the stallion, a technique was developed for semen collection that pharmacologically induces ejaculation without copulation (ex copula). This study investigates whether semen could be reliably collected by ex copula ejaculation in male alpacas. Eleven male Huacaya alpacas were used in this study, and six ex copula treatment protocols were evaluated: (1) saline (control); (2) xylazine only (0.1 mg/kg); (3) xylazine only (0.2 mg/kg); (4) imipramine only (1.0 mg/kg); (5) imipramine (1.0 mg/kg) followed 10 minutes later with xylazine (0.1 mg/kg); and (6) imipramine (2.0 mg/kg) followed 10 minutes later with xylazine (0.1 mg/kg). Each treatment protocol was repeated two to five times. Azoospermic samples obtained from ex copula ejaculation contained numerous epithelial cells but no sperm. A reliable treatment for pharmacologically inducing ejaculation in alpacas remains to be found.     

Premature ventricular contractions of the right ventricular outflow tract: is there an incipient underlying disease? New insights from a speckle tracking echocardiography study

ContextPremature ventricular contractions (PVCs) originating in the right ventricular outflow tract (RVOT) are traditionally considered idiopathic and benign. Echocardiographic conventional measurements are typically normal.AimsTo assess whether right ventricle longitudinal strain, determined by two-dimensional speckle tracking echocardiography, differ between RVOT PVCs patients (treated with catheter ablation) and healthy controls.MethodsWe retrospectively selected patients with PVCs from the RVOT who underwent electrophysiological study and catheter ablation between 2016 and 2019. Patients with documented structural heart disease were excluded. Transthoracic echocardiography was performed and right ventricle global longitudinal strain (RV-GLS), free wall longitudinal strain (RVFW-LS) and left ventricle global longitudinal strain (LV-GLS) were determined as well as conventional ultrasound measurements of RV and LV function.ResultsWe studied 21 patients with RVOT PVCs and 13 controls. Patients with PVCs from the RVOT had lower values of RV-GLS and RVFW-LS compared with the control group (?19.4% versus ?22.5%, P = 0.015 and ?22.1% versus ?25.5, P = 0.041, respectively). They also had lower values of LV-GLS, although still within the normal range (?19.1% versus ?20.9%, P = 0.047). Regarding RVOT PVCs patients only, RV-GLS and RVFW-LS had no correlation with the PVCs burden prior to catheter ablation and they did not differ between the patients in whom the catheter ablation was successful and those in whom it was not. RV-GLS also had a positive correlation with RVOT proximal diameter (r = 0.487, P = 0.025).ConclusionsIn this group of RVOT PVCs patients, we found worse RV longitudinal strain values (and therefore sub-clinical myocardial dysfunction) when compared to healthy controls.