ObjectiveAutophagy is activated in ischemic heart diseases, but its dynamics and functional roles remain unclear and controversial. In this study, we investigated the dynamics and role of autophagy and the mechanism(s), if any, during postinfarction cardiac remodeling.Methods and resultsAcute myocardial infarction (AMI) was induced by ligating left anterior descending (LAD) coronary artery. Autophagy was found to be induced sharply 12–24 hours after surgery by testing LC3 modification and Electron microscopy. P62 degradation in the infarct border zone was increased from day 0.5 to day 3, and however, decreased from day 5 until day 21 after LAD ligation. These results indicated that autophagy was induced in the acute phase of AMI, and however, impaired in the latter phase of AMI. To investigate the significance of the impaired autophagy in the latter phase of AMI, we treated the mice with Rapamycin (an autophagy enhancer, 2.0 mg/kg/day) or 3-methyladenine (3MA, an autophagy inhibitor, 15 mg/kg/day) one day after LAD ligation until the end of experiment. The results showed that Rapamycin attenuated, while 3MA exacerbated, postinfarction cardiac remodeling and dysfunction respectively. In addition, Rapamycin protected the H9C2 cells against oxygen glucose deprivation in vitro. Specifically, we found that Rapamycin attenuated NFκB activation after LAD ligation. And the inflammatory response in the acute stage of AMI was significantly restrained with Rapamycin treatment. In vitro, inhibition of NFκB restored autophagy in a negative reflex.ConclusionSustained myocardial ischemia impairs cardiomyocyte autophagy, which is an essential mechanism that protects against adverse cardiac remodeling. Augmenting autophagy could be a therapeutic strategy for acute myocardial infarction.

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Transforming growth factor beta (TGF-β) is suggestive of a molecular target for cancer therapy due to its involvement in cell cycle, differentiation, and morphogenesis. Meanwhile, survivin is identified as an apoptosis inhibitor and involved in tumorgenesis. Here, we aimed to investigate the potential associations between TGF-β and survivin in glioblastoma U87 cell line. Survivin small interfering RNA (siRNA), Western blotting, and cell cycle analysis were introduced to detect relevant proteins in TGF-β pathways. In this study, we observed a concentration- and time-dependent increase of survivin expression after treatment with TGF-β1. However, the kinase inhibitors U0126 and LY294002 inhibited the upregulation of survivin in comparison with DMSO. In addition, survivin siRNA effectively abrogated survivin expression in U87 cells, therefore affected cells' entry into the S phase of cell cycle, and then repressed the expression of epidermal growth factor receptor (EGFR) and matrix metalloproteinase 9 (MMP9) in comparison with non-transfection. In conclusion, the present study shows that TGF-β upregulates survivin expression via ERK and PI3K/AKT pathway, leading to glioblastoma cell cycle progression. Thus, the blockade of survivin will allow for the treatment of glioblastoma, partially attributing to the inhibition of EGFR and MMP9 expression.

Background The postgraduate entrance examination can be a milestone for many medical students to advance their careers. An increasing number of students are competing for limited postgraduate offers available, and failure to enter postgraduate studies can have adverse mental health consequences. In this paper, we aim to investigate the mental health status of medical students during the postgraduate application entrance examination and to provide a targeted basis for mental health education and psychological counselling. Methods Using the Symptom Checklist-90 scale (SCL-90) questionnaire, the mental health status of 613 students who passed two rounds of the Postgraduate Entrance Examination in 2019 to enroll in Guangzhou Medical University in China was evaluated and followed up for retesting 6 months later. We used SPSS 20.0 statistical software for comparative analysis, including One-Sample T-Test, Independent-Samples T-Test, Paired Samples T-Test and Chi-square Test. Results Our data showed that 12.10% of students had mental health problems during the postgraduate entrance examination, and it decreased significantly to 4.40% at the 6-month follow-up after the examination period finished (P < 0.01). Somatization was the most significant symptom of the students both during and after the postgraduate entrance examination stages. All SCL-90 factors were scored significantly lower both in and after the postgraduate entrance examination stages than the 2008 national college student norm score (P < 0.01). Excluding psychiatric factors, all other SCL-90 factors in the postgraduate entrance examination stage scored higher than the graduate stage (P < 0.05), and the total score of SCL-90 in female medical students was higher compared to male students (P < 0.05). Conclusion The postgraduate entrance examination event has a significant negative influence on students’ mental health. The mental health of college and graduate students as an important part of their higher education experience should be systematically studied, and psychological counselling or help should be provided to them throughout their studies, specifically during the examination period. Educating applicants about mental health should be implemented during the postgraduate entrance examination curriculum.

Corrigendum to increased expression of DRAM1 confers myocardial protection against ischemia via restoring autophagy flux [