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Objective To analyze the role and molecular mechanisms underlying of ubiquitin C-terminal hydrolase 1 (UCHL1) in promoting atrial fibrillation (AF). Methods Forty 8-week-old male SD rats (240~260 g) were randomly divided into four groups, with 10 rats in each group: Sham+DMSO group, Sham+ LDN (the inhibitor of UCHL1) group, AF+DMSO group and AF+LDN group. AF model was induced by subcutaneously implanted osmotic micropump of angiotensin Ⅱ (AngⅡ) in both AF+DMSO group and AF+LDN group. After 4 weeks, the duration of AF was monitored and recorded by electrocardiography. The level of fibrosis was observed by Masson-trichrome staining of left atrial tissues. Heart function was evaluated by ultrasonic cardiography. Neonatal rat cardiomyocytes (NRCM) were isolated from the hearts of SD rats aged 1~3 d of which effect was verified by overexpression or knockdown of UCHL1 in NRCM cells. Immunoprecipitation mass spectrometry was used to evaluate the functional regulatory mechanism of UCHL1 on calcium/calmodulin-dependent protein kinaseⅡ (CaMKⅡ) in NRCM. The expression of fibrotic protein was analyzed by Western blot assay. Results The expression of UCHL1 protein was increased in cardiac tissues of AF rats and in AngⅡ-treated NRCM. Compared with the AF+DMSO group, the cardiac ejection fraction (EF) and fractional shortening (FS) of the AF+LDN group were significantly increased (P < 0.01), while the degree of fibrosis, expression of α-SMA and ColⅠ and duration of AF were significantly decreased(P < 0.01). In vitro, inhibition and knockdown of UCHL1 attenuated AngⅡ-induced fibrosis of NRCM (P < 0.05). Immunoprecipitation mass spectrometry revealed that UCHL1 interacted with CaMKⅡ in NRCM simulated by AngⅡand promoted the upregulation of UCHL1 through deubiquitination. CaMKⅡ overexpression reduced the inhibitory effect of UCHL1 knockdown on the fibrotic response in AngⅡ-induced NRCM (P < 0.05). Conclusion UCHL1 interacts with CaMKⅡ and upregulates CaMKⅡ through deubiquitination, thereby promoting cardiac fibrosis in AF.

Objective To evaluate the effectiveness of Ommaya sac combined with external ventricular drainage in improving neurological function after periventricular-intraventricular hemorrhage (PIVH) in neonates. Methods A retrospective cohort study was carried out on the neonates hospitalized due to PIVH in the neonate and neurosurgery departments in our hospital from January 2015 to July 2020. They were divided into Ommaya sac combined with external ventricular drainage surgery group (surgery group) and non-surgery group. All of them were followed up until they were 12 months old. The concentration of inflammatory factors in cerebrospinal fluid in the early stage, the incidence of complications (epilepsy, hydrocephalus, cerebral palsy, and death) during follow-up, and neurodevelopmental outcomes were observed and analyzed in the 2 groups. Results A total of 71 PIVH neonates were enrolled, including 35 cases treated with Ommaya capsule combined with external ventricular drainage, and 36 cases treated without surgery. The levels of neuron enolase (NSE), nerve growth factor (NGF) and neutrophil-to-lymphocyte ratio (NLR) in the cerebrospinal fluid in 3 d after surgery were significantly decreased than the levels before surgery (P < 0.05). In the non-surgery group, no such differences in the above indexes were seen in 3 d after treatment (P>0.05). During the follow-up to 12 months of corrected age, 1 neonate (2.9%) died in the surgery group and 6 neonates (16.7%) died in the non-surgery group. The incidences of complications in the surgery group and non-surgery group were compared as follows: epilepsy (0 vs 2 cases), hydrocephalus (4 vs 9 cases) and cerebral palsy (1 vs 3 cases), and statistical differences were seen in the incidences (P < 0.05). Gesell Developmental Scale score indicated that the developmental of the surviving children in the surgery group were significantly better than those in the non-surgery group in terms of adaptability, fine motor, language and personal social interaction (all P < 0.05). Conclusion Compared with non-surgical treatment, Ommaya sac combined with external ventricular drainage significantly reduces the concentration of inflammatory factors in the cerebrospinal fluid of neonates with moderate and severe PIVH, effectively decreases the incidence of PIVH complications, and improves the prognosis of neurological function.

Online teaching has been massively conducted during the novel coronavirus period all over the world. How to evaluate online teaching has been increasingly researched recently. This study looked at how English as a foreign language (EFL) teaching was delivered online by university teachers during the COVID-19 pandemic. We investigated university teachers and students' perception of effective EFL online teaching and learning based on several evaluation modes in using technology in education. Data were collected using questionnaires and interviews from teachers and students in a variety of provinces in Mainland China. The results showed that various methods were used to deliver online EFL courses and these approaches are found to correlate with each other. Teachers and students provided positive comments on online teaching and were satisfied with their online teaching and learning. Participants also noted effective ways in online EFL teaching. The findings indicated that when teachers have more training, more skills, and more confidence, they could deliver more effective online teaching and learning.

ABSTRACT ChatGPT has garnered significant interest for its potential educational benefits, particularly in aiding English as a foreign language (EFL) learners to develop language skills. This study aims to explore how various internal and external factors, as outlined in the proposed extended technology acceptance model (TAM), influence EFL learners’ acceptance and use of ChatGPT to enhance their oral English. Drawing on the extended TAM questionnaires from 212 Chinese EFL learners and semi‐structured interviews with 12 participants, the research underscores that a positive attitude toward ChatGPT significantly influences learners’ intention to adopt ChatGPT for English‐speaking practice. Moreover, facilitating conditions significantly predict the perceived ease of use. The qualitative results shed light on ChatGPT's effectiveness and convenience in developing English‐speaking skills, its potential to simulate IELTS exams and situational dialogues, and identifying certain scenario‐specific limitations. [ABSTRACT FROM AUTHOR]