Inverted Classroom Teaching of Physiology in Basic Medical Education: Bibliometric Visual Analysis.

Background: Over the last decade, there has been growing interest in inverted classroom teaching (ICT) and its various forms within the education sector. Physiology is a core course that bridges basic and clinical medicine, and ICT in physiology has been sporadically practiced to different extents globally. However, students' and teachers' responses and feedback to ICT in physiology are diverse, and the effectiveness of a modified ICT model integrated into regular teaching practice in physiology courses is difficult to assess objectively and quantitatively. Objective: This study aimed to explore the current status and development direction of ICT in physiology in basic medical education using bibliometric visual analysis of the related literature. Methods: A bibliometric analysis of the ICT-related literature in physiology published between 2000 and 2023 was performed using CiteSpace, a bibliometric visualization tool, based on the Web of Science database. Moreover, an in-depth review was performed to summarize the application of ICT in physiology courses worldwide, along with identification of research hot spots and development trends. Results: A total of 42 studies were included for this bibliometric analysis, with the year 2013 marking the commencement of the field. University staff and doctors working at affiliated hospitals represent the core authors of this field, with several research teams forming cooperative relationships and developing research networks. The development of ICT in physiology could be divided into several stages: the introduction stage (2013-2014), extensive practice stage (2015-2019), and modification and growth stage (2020-2023). Gopalan C is the author with the highest citation count of 5 cited publications and has published 14 relevant papers since 2016, with a significant surge from 2019 to 2022. Author collaboration is generally limited in this field, and most academic work has been conducted in independent teams, with minimal cross-team communication. Authors from the United States published the highest number of papers related to ICT in physiology (18 in total, accounting for over 43% of the total papers), and their intermediary centrality was 0.24, indicating strong connections both within the country and internationally. Chinese authors ranked second, publishing 8 papers in the field, although their intermediary centrality was only 0.02, suggesting limited international influence and lower overall research quality. The topics of ICT in physiology research have been multifaceted, covering active learning, autonomous learning, student performance, teaching effect, blended teaching, and others. Conclusions: This bibliometric analysis and literature review provides a comprehensive overview of the history, development process, and future direction of the field of ICT in physiology. These findings can help to strengthen academic exchange and cooperation internationally, while promoting the diversification and effectiveness of ICT in physiology through building academic communities to jointly train emerging medical talents.

Recapitulation of Structure-Function-Regulation of Blood-Brain Barrier under (Patho)Physiological Conditions.

The blood-brain barrier (BBB) is a remarkable and intricate barrier that controls the exchange of molecules between the bloodstream and the brain. Its role in maintaining the stability of the central nervous system cannot be overstated. Over the years, advancements in neuroscience and technology have enabled us to delve into the cellular and molecular components of the BBB, as well as its regulation. Yet, there is a scarcity of comprehensive reviews that follow a logical framework of structure-function-regulation, particularly focusing on the nuances of BBB regulation under both normal and pathological conditions. This review sets out to address this gap by taking a historical perspective on the discovery of the BBB and highlighting the major observations that led to its recognition as a distinct brain barrier. It explores the intricate cellular elements contributing to the formation of the BBB, including endothelial cells, pericytes, astrocytes, and neurons, emphasizing their collective role in upholding the integrity and functionality of the BBB. Furthermore, the review delves into the dynamic regulation of the BBB in physiological states, encompassing neural, humoral, and auto-regulatory mechanisms. By shedding light on these regulatory processes, a deeper understanding of the BBB's response to various physiological cues emerges. This review also investigates the disruption of the BBB integrity under diverse pathological conditions, such as ischemia, infection, and toxin exposure. It elucidates the underlying mechanisms that contribute to BBB dysfunction and explores potential therapeutic strategies that aim to restore the BBB integrity and function. Overall, this recapitulation provides valuable insights into the structure, functions, and regulation of the BBB. By integrating historical perspectives, cellular elements, regulatory mechanisms, and pathological implications, this review contributes to a more comprehensive understanding of the BBB and paves the way for future research and therapeutic interventions.

Physiology education and teaching in Chinese mainland medical schools: the status quo and the changes over the past two decades.

Physiology is a critical subject that bridges basic and clinical medicine. The reform of physiology education is crucial to improving the quality of teaching and supporting student learning; however, there is a lack of comprehensive data documenting the current state of physiology education in medical programs in China. This study conducted an online survey among experienced teachers from the top 100 medical schools in the Chinese mainland in 2022. A total of 89 valid questionnaires were included in this study. In 57.3% of the surveyed medical schools, 70% of the physiology teachers have a Ph.D. degree, while the number of faculty members with a medical background has tended to decrease in 53.9% of the surveyed medical schools. Of the 89 medical schools, 62 have implemented physiology course integration, with 69.4% of the respondents believing that curriculum integration could enhance students' knowledge acquisition and application. The lecture hours per term are 50-70 and 71-90 in 49.4% and 42.7% of the 89 medical schools, respectively. The ratio of course duration of lecture to laboratory was 2:1 in 47.2% of the surveyed medical schools, while the ratio was between 1:1 and 2:1 in 47.2% of the surveyed medical schools, and only 5.6% of medical schools opted for a 1:1 course arrangement. For teaching methods, about 60% of medical schools used problem-based learning, case-based learning, and task-based learning (PBL/CBL/TBL) for clinical medicine students only, and 25.4% of medical schools applied PBL/CBL/TBL to all students. This study is conducive to promoting dialogue and communication among physiology teachers, administrators, and researchers.NEW & NOTEWORTHY This study conducted a nationwide survey of the top 100 medical schools in the Chinese mainland in 2022 to provide first-hand data on the current situation and changes in physiology education and teaching in the Chinese mainland with focuses on the faculty composition, curriculum integration, teaching methods, and assessment modes, which is a microcosm of the reform and development of the medical education in the Chinese mainland, hoping to improve the quality of preclinical medical education.

Safety and effectiveness of an iris hook assisted phacoemulsification in vitrectomized eyes.

AIM: To introduce a simple iris hook assisted phacoemulsification (PE) procedure and evaluate the safety and efficacy of it in completely vitrectomized eyes. METHODS: A single centre study which included 65 previously completely vitrectomized eyes of 62 patients who underwent cataract surgery. Patients were randomly divided into 3 groups. Patients received PE, and intraocular lens (IOL) implantation with the assistance of iris hook (Synergeties™) as group A (25 eyes); patients who received PE assisted with a 25G pars plana irrigation as group B (20 eyes), and patients who received PE performed without the help of any instrument as group C (20 eyes). Main outcome measures were surgery duration, Ultrasound (U/S) total time, endothelial cell density (ECD), cumulative dissipated energy (CDE) and complications of the procedures. RESULTS: With the help of iris hook, the patients in group A had the lowest ECD loss rate (0.07±0.03, 0.09±0.03, and 0.10±0.03, P<0.05), shortest CDE (12.2±4.1, 15.8±6.0, and 16.0±6.0, P<0.05) and U/S total time (36.6±13.0s, 46.3±16.4s, and 47.6±16.1s, P<0.05), and minimal incidence of complications. The longest surgery duration was in group B (19.4±1.6min) and maximum complications rate in group C (20% miosis, 10% posterior capsular tears, 5% zonular dialysis, 5% cystoid macular edema). While best-corrected visual acuity (BCVA), intraocular pressure (IOP) and ECD did not show a significant difference among the three groups. CONCLUSION: Without prolonged surgery duration, the iris hook assistant method can minimize heat generation during surgery and incidence of complications, which transfer the challenged PE in vitrectomized eyes into a regular surgery. It does not need any change in the hydrodynamic parameters and in the bag PE technique, easy to operate even for junior surgeons.

PLK2 protects retinal ganglion cells from oxidative stress by potentiating Nrf2 signaling via GSK-3ß.

Oxidative stress of retinal ganglion cells (RGCs) has been established as a main contributor to retinal degeneration in the pathogenesis of glaucoma. Polo-like kinase 2 (PLK2) has recently been reported to be a potent antioxidant protein that enhances cell survival in response to oxidative stress. To date, the involvement of PLK2 in RGC-associated oxidative stress is undermined. In the present work, we evaluated whether PLK2 regulates oxidative stress evoked by hydrogen peroxide (H2 O2 ) in RGCs. PLK2 expression was induced by H2 O2 stimulation in RGCs. Upregulation of PLK2 had a profoundly cytoprotective effect on H2 O2 -stimulated RGCs by attenuating cellular apoptosis and reactive oxygen species (ROS) level. Further data revealed that upregulation of PLK2 strikingly enhanced the activation of Nrf2 signaling. Moreover, PLK2 overexpression promoted glycogen synthase kinase (GSK)-3ß phosphorylation, whereas PLK2 knockdown reduced the levels of GSK-3ß phosphorylation. Notably, GSK-3ß inhibition using a chemical inhibitor markedly abrogated the suppressive effects of PLK2 knockdown on Nrf2 activation. Repression of Nrf2 blocked the PLK2 overexpression-induced protective effects in H2 O2 -stimulated RGCs. Overall, this study elucidates that upregulation of PLK2 protects RGCs against H2 O2 -induced oxidative stress injury by upregulating Nrf2 activation via modulation of GSK-3ß phosphorylation. These findings underline the pivotal role of PLK2 in mediating oxidative stress-evoked retinal degeneration in the pathogenesis of glaucoma.

[Effects of rAAV-mediated rhBDNF gene transfection on BDNF gene expression in the retina of a rabbit model of acute high intraocular pressure].

OBJECTIVE: To observe the changes in the expression of brain derived neurotrophic factor (BDNF) gene in the retina of rabbits with acute high intraocular pressure (IOP) after injection of recombinant adeno-associated virus (rAAV) vector containing human BDNF gene (rAAV-hBDNF), and investigate the neuroprotective mechanism of rAAV-hBDNF. METHODS: The unilateral eyes of 24 white rabbits were randomly chosen as the model group with high IOP induced by saline perfusion into the anterior chamber, and the contralateral eyes served as the control group without treatment. In another 24 white rabbits, 10 microl rAAV-BDNF was injected into the vitreous body of one of the eyes 3 days before induction of high IOP. On days 1, 3, 7, and 14 after perfusion, the bilateral eyes of 6 rabbits were excised for immunohistochemistry for the expression of endogenous BDNF gene in the retina. RESULTS: The number of BDNF-positive cells in the retina decreased after induction of high IOP, and injection of rAAV-hBDNF resulted in a significant increase in BDNF-positive cells as compared with the positive cell number in the high IOP model and control groups (P<0.05, P<0.01). CONCLUSION: rAAV-mediated BDNF gene transfection can increase endogenous BDNF expression in the retina of rabbits with acute high IOP. Intravitreous injection is an effective pathway for rAAV-hBDNF gene transfection into the retina.

[Neuroprotective effect of rAAV-mediated rhBDNF gene transfection on rabbit retina against acute high intraocular pressure].

OBJECTIVE: To investigate the neuroprotective effect of human brain-derived neurotrophic factor gene transfection into rabbit retina against acute high intraocular pressure (HIOP). METHODS: Acute HIPO was induced in one eye of 24 white rabbits via saline perfusion into the anterior chamber (model group), and the contralateral eye without treatment served as the control group. In another 24 rabbits, 10 microl recombinant adeno-associated virus (rAAV) vector containing human BDNF gene (rAAV-BDNF) was injected into the vitreous body of one of the eyes 3 days before the operation for HIPO (BDNF group). At 1, 3, 7, and 14 days after HIOP model establishment, 6 eyes in each group were excised to observe the number of retinal ganglion cells (RGCs) and the thickness of the inner retina layer. For the eyes dissected on day 14, electroretinogram b (ERG-b) wave was detected 30 min before (baseline) and on days 1, 3, 7 and 14 after HIOP. Another 5 rabbits were used for ultrastructural observation of the RGCs using transmission electron microscopy, including 1 without treatment, 2 with unilateral HIOP and 2 with rAAV-BDNF transfection before HIOP. RESULTS: The amplitude of ERG-b wave showed no significant difference between the 3 groups before HIOP (P>0.05). In HIOP model group and BDNF group, the amplitude decreased to the lowest at 1 day after HIOP and failed to recover the baseline level at 14 days (P<0.01); at the end of the observation, the amplitude was significantly higher in BDNF group than in the model group (P<0.01). Decreased number of RGCs and thickness of inner retina layer occurred in the model group, but these changes were milder in BDNF group (P<0.05, P<0.01). Electron microscopy revealed ultrastructural changes in the RGCs following acute HIOP, and transfection with rAAV-BDNF ameliorated these changes. CONCLUSION: rAAV-BDNF transfection protects the retinal structure and improves the amplitude of ERG-b wave after acute high IOP suggesting its neuroprotective effects.

[The effects of recombinant human erythropoietin on electroretinogram after raising intraocular pressure in rabbits].

PURPOSE: To investigate the protective effect of recombinant human erythropoietin (rhEPO) on retinal ischemic injury induced by raising intraocular pressure. METHODS: Twelve New Zealand rabbits were divided into the model group (n=6) and the EPO group (n=6). Either of bilateral eyes was randomly made into the acutely high intraocular pressure model using the method of saline perfusion into anterior chamber. After the model was made, rhEPO 100 IU x kg(-1) was injected into the hypodermic tissue of EPO group rabbits twice a week for one week. Flash electroretinogram (ERG) was detected 30 min before and at 1, 3, 7, and 14 days after perfusion, respectively. RESULTS: The amplitude of ERG-b wave had no significant difference in the EPO group compared with that in the model group before anterior chamber perfusion (P > 0.05). The amplitude of ERG-b wave dropped down to the lowest at 1 day after perfusion and could not come back to the baseline in the model group (P < 0.05). The resemble situation was in the EPO group except that the amplitude of ERG-b wave came back to the baseline at 14 days (P > 0.05). CONCLUSION: EPO can improve the amplitude of ERG-b wave following retinal ischemia. This indicates that EPO has the potential to be an optimal neuroprotective agent.