BACKGROUND:Peripheral nerve axon rupture seriously affects patients' physical function and mental health.Microsurgery,nerve autograft,nerve allograft,fibrin glue and catheter technology are the main treatments for peripheral nerve injury,each of which has its own advantages and disadvantages,but the overall treatment effect is not satisfactory.Despite the clinical success of Schwann cells in promoting axonal regeneration,there are still many challenges in the treatment with Schwann cells,such as slow expansion of Schwann cells,immune rejection,and low survival rate of transplanted cells.OBJECTIVE:To summarize the role and mechanism of Schwann cells in promoting the regeneration of peripheral nerve axons,and the difficulties and challenges of Schwann cells in the process of nerve regeneration treatment.METHODS:PubMed,Medline,WanFang,VIP,and CNKI were searched by computer using the search terms of"Schwann cells,synaptic Schwann cell,macrophage,peripheral nerve axon rupture,Wallerian degeneration,Peripheral nerve axon regeneration,Central nervous system repair"in English and Chinese.Literature related to Schwann cell proliferation and differentiation,promotion of peripheral nerve regeneration,and clinical applications was retrieved from database inception to October 2024,and a total of 95 articles were finally included for review.RESULTS AND CONCLUSION:Schwann cells interact with macrophages,T cells and other cells,to initiate the regeneration process through signaling pathways,including Krox20/C-Jun,NRG-1/ErbB,Notch,MAPK,and PI3K/Akt/mTOR,synthesize and release nerve growth factors,and thus promote regeneration of the peripheral nervous system.Schwann cells have been experimentally demonstrated to have great potential in peripheral nerve repair and are expected to become the key target of therapeutic intervention.However,there are still problems such as difficulties in cell harvest and culture,as well as the occurrence of other diseases during the treatment process.

BACKGROUND:Peripheral nerve axon rupture seriously affects patients' physical function and mental health.Microsurgery,nerve autograft,nerve allograft,fibrin glue and catheter technology are the main treatments for peripheral nerve injury,each of which has its own advantages and disadvantages,but the overall treatment effect is not satisfactory.Despite the clinical success of Schwann cells in promoting axonal regeneration,there are still many challenges in the treatment with Schwann cells,such as slow expansion of Schwann cells,immune rejection,and low survival rate of transplanted cells.OBJECTIVE:To summarize the role and mechanism of Schwann cells in promoting the regeneration of peripheral nerve axons,and the difficulties and challenges of Schwann cells in the process of nerve regeneration treatment.METHODS:PubMed,Medline,WanFang,VIP,and CNKI were searched by computer using the search terms of"Schwann cells,synaptic Schwann cell,macrophage,peripheral nerve axon rupture,Wallerian degeneration,Peripheral nerve axon regeneration,Central nervous system repair"in English and Chinese.Literature related to Schwann cell proliferation and differentiation,promotion of peripheral nerve regeneration,and clinical applications was retrieved from database inception to October 2024,and a total of 95 articles were finally included for review.RESULTS AND CONCLUSION:Schwann cells interact with macrophages,T cells and other cells,to initiate the regeneration process through signaling pathways,including Krox20/C-Jun,NRG-1/ErbB,Notch,MAPK,and PI3K/Akt/mTOR,synthesize and release nerve growth factors,and thus promote regeneration of the peripheral nervous system.Schwann cells have been experimentally demonstrated to have great potential in peripheral nerve repair and are expected to become the key target of therapeutic intervention.However,there are still problems such as difficulties in cell harvest and culture,as well as the occurrence of other diseases during the treatment process.

Objective:To investigate the distribution of CGG repeat numbers in the FMR1 gene among reproductive-age women in China, providing data reference for carrier screening and genetic counseling of Fragile X syndrome. Methods:This cross-sectional study recruited 16 610 reproductive-age women from 12 medical institutions between July 2022 and October 2023. Peripheral venous blood samples (3 mL) were collected, and genomic DNA was extracted. The number of CGG repeats in the FMR1 gene was determined using the triplet-primed polymerase chain reaction (TP-PCR) combined with capillary electrophoresis technology. Statistical analyses were performed to assess the prevalence and distribution of CGG repeat expansions. Results:Among 16 610 women of childbearing age, 5 684 (34.220%) women had the same number of CGG repeats in the two alleles of FMR1 gene, and 10 926 (65.780%) women had different numbers of repeats in the two alleles. Among the 33 220 FMR1 alleles in 16 610 women of reproductive age, the most common CGG repeat numbers were 29 [48.645% (16 160/33 220)] and 30 [26.276% (8 729/33 220)], while the most frequent CGG genotype was CGG 29/29 [24.726% (4 107/16 610)]. The CGG repeat numbers of FMR1 gene were normal in 16 498 women (99.326%). Among the 112 women (0.674%) with CGG repeat abnormities, 96 (0.578%) women were classified as intermediate carriers, 15 (0.090%) as premutation carriers, and 1 (0.006%) as a full mutation carrier, whose CGG genotype was (36, >200). Conclusion:In the general reproductive-age female population in China, the normal CGG repeat numbers of the FMR1 gene account for 99.326%, while the intermediate carrier rate is 0.578%, and the combined carrier rate of the premutation and full mutation types is 0.096%.

Objective:To investigate the outcomes of natural cycle (NC) and modified natural cycle (MNC) assisted reproductive technology (ART) in patients with diminished ovarian reserve (DOR), and to provide a scientific basis for individualized treatment strategies for DOR patients.Methods:A retrospective cohort analysis was performed on the clinical data of DOR patients who underwent ART at the Center for Reproductive Medicine of the Department of Obstetrics and Gynecology, Peking University Third Hospital from January 1, 2015 to December 31, 2023. Patients were divided into the NC group ( n=801) and the MNC group ( n=385) based on their treatment protocol. The primary outcomes were cycle cancellation rate and oocyte retrieval rate. Secondary outcomes included clinical pregnancy rate and live birth rate per fresh embryo transfer cycle and frozen-thawed embryo transfer cycle, cumulative pregnancy rate and cumulative live birth rate per started cycle and per transfer cycle, as well as laboratory parameters such as the number of retrieved oocytes, the number of two pronuclei (2PN) fertilized oocytes, the number of transferable embryos, and transferable embryo formation rate. Further, multivariate logistic regression was used to analyze the impact of the treatment protocol on pregnancy and live birth outcomes. Results:There were no statistically significant differences between the NC and MNC groups in terms of general characteristics such as age, body mass index, and baseline hormone levels (all P>0.05). The cycle cancellation rate was significantly higher in the NC group [19.10% (153/801)] than in the MNC group [10.65% (41/385), P<0.001], and the oocyte retrieval rate was significantly lower in the NC group [66.31% (431/650)] than in the MNC group [74.86% (259/346), P=0.005]. The number of retrieved oocytes [1 (0,1)], the number of 2PN fertilized oocytes [1 (0,1)], and the number of transferable embryos [0 (0, 1)] were also significantly lower in the NC group than in the MNC group [1 (1, 2), P<0.001; 1 (1, 1), P<0.001; 0 (0, 1), P<0.001]. However, there were no statistically significant differences in 2PN fertilization rate and transferable embryo formation rate between the NC and MNC groups (all P>0.05). In both fresh embryo transfer cycles and frozen-thawed embryo transfer cycles, there were no statistically significant differences in clinical pregnancy rate and live birth rate between the NC and MNC groups (all P>0.05). The cumulative pregnancy rate per started cycle and transfer cycle, the cumulative live birth rate per started cycle and per transfer cycle were also not significantly different between the NC and MNC groups (all P>0.05). Multivariate logistic analysis showed no significant association between NC and clinical pregnancy or live birth compared with MNC. Conclusion:While MNC to some extent reduced the cycle cancellation rate and improved oocyte retrieval rates compared with NC, it did not ultimately improve pregnancy outcomes in DOR patients.

Objective:To evaluate the effect of baicalein on acute myocardial injury in rats with high-level spinal cord injury (SCI) and the role of nuclear factor E2-related factor 2 (Nrf2).Methods:Twenty-four clean-grade healthy male Sprague-Dawley rats, aged 8-10 weeks, weighing 250-300 g, were divided into 4 groups ( n=6 each) using a random number table method: sham operation group (Sham group), SCI group, SCI+ baicalein group (SCI+ Bai group) and SCI+ baicalein+ ML385 group (SCI+ Bai+ ML385 group). The high-level SCI rat model was established by the modified Allens method. In Sham group, the 7th cervical vertebra (C 7) was only exposed, but the spinal cord was not hit. In SCI group, C 7 was exposed and the spinal cord was hit. In SCI+ Bai group, baicalein 50 mg/kg was intraperitoneally injected immediately after SCI. In SCI+ Bai+ ML385 group, Nrf2 inhibitor ML385 30 mg/kg was intraperitoneally injected at 1 h before SCI, and baicalein 50 mg/kg was intraperitoneally injected immediately after SCI. The rats were anesthetized at 24 h after SCI and sacrificed after the blood samples from the abdominal aorta were collected and the hearts were taken for microscopic examination of the pathological changes (by HE staining) which were scored and the ultrastructure of cells (with a transmission electron microscope) and for determination of the serum cardiac troponin I (cTnI) concentrations (by enzyme-linked immunosorbent assay), content of ferrous ion (Fe 2+ ) in myocardial tissues (by colorimetry), contents of malondialdehyde(MDA) and glutathione (GSH) and activity of superoxide dismutase(SOD) in myocardial tissues (by biochemical method) and expression of glutathione peroxidase 4 (GPX4), acyl CoA synthase long chain family member 4 (ACSl4) and Nrf2 protein and mRNA in myocardial tissues (by Western blot and fluorescent quantitative polymerase chain reaction). The mitochondrial Flameng score was assessed and recorded. Results:Compared with Sham group, the pathological score, mitochondrial Flameng score and serum cTnI concentrations were significantly increased, the contents of Fe 2+ and MDA in myocardial tissues were increased, the content of GSH and SOD activity were decreased, the expression of GPX4 was down-regulated, and the expression of ACSL4 and Nrf2 was up-regulated in SCI group ( P<0.05). Compared with SCI group, the pathological score, mitochondrial Flameng score and serum cTnI concentration were significantly decreased, the contents of Fe 2+ and MDA in myocardial tissues were decreased, the contents of GSH and SOD activity were increased, the expression of GPX4 and Nrf2 was up-regulated, and the expression of ACSL4 was down-regulated in SCI+ Bai group ( P<0.05). Compared with SCI+ Bai group, the pathological score, mitochondrial Flameng score and serum cTnI concentrations were significantly increased, the contents of Fe 2+ and MDA in myocardial tissues were increased, the content of GSH and SOD activity were decreased, the expression of GPX4 and Nrf2 was down-regulated, and the expression of ACSL4 was up-regulated in SCI+ Bai+ ML385 group ( P<0.05). Conclusions:Baicalein can alleviate acute myocardial injury in rats with high-level SCI, and Nrf2 is involved in this process.

Prescription sequence symmetry analysis (PSSA) is one of the important methods for post-marketing pharmacovigilance based on the real-world medical prescription databases. It can be used to detect prescription cascades and mine adverse drug reaction (ADR) signals, which has been verified by many studies. PSSA shows high specificity and medium sensitivity in identifying ADR. It can quantify the correlation or risks of ADR. It is easy to use and simple in algorithm, and it has good robustness to some non time-dependent confounding factors. However, the results may be affected by some human confounding factors and data quality. This paper reviews the principle, calculation method, application scope, and precaution of PSSA by reviewing related literature on PSSA domestically and abroad, in order to provide reference for pharmacovigilance in China.

Objective:To understand the application situation and role of prescription sequence symmetry analysis (PSSA) in pharmacovigilance.Methods:The relevant databases at home and abroad were searched (up to April 30, 2024), and the original articles using PSSA as the research method were collected. The basic information of the literature (first author, publication year, country, etc.), the purpose and main content of the study, the index drugs as well as the marker drugs or medical diagnoses involved in the adverse drug reactions (ADRs) were extracted. Descriptive statistical analysis was carried out.Results:A total of 66 articles were included in the analysis. The first article was published in 1996, the number of articles published in recent years has increased significantly, and those published after 2016 accounted for 68.2% (45/66). The top 3 countries in terms of published literature quantity were the United States, Denmark, and Japan. The index drugs most commonly studied were those for the cardiovascular system and the neuropsychiatric system, in 18 and 14 articles respectively. The drugs studied in 3 or more papers were hypolipidemic drugs, antihypertensive drugs, antipsychotics, antiepileptics, proton pump inhibitors, hypoglycemic drugs and anticoagulants. The targeted ADRs/diseases most studied were those about the neuropsychiatric system (in 13 studies), followed by those about the endocrine and metabolic system (in 12 studies). The research objective in 47 articles was to explore the association between index drugs and ADRs/diseases through PSSA. Finally, the associations between 21 ADRs and index drugs were identified in 24 articles, of which 9 were new ADRs not recorded in drug instructions; benefits or potential preventive and therapeutic effects of index drugs on certain diseases were found in 7 studies. Ten studies were conducted to explore ADR information of specific drugs or detect suspicious drugs that cause specific ADRs, and some correlation signals between drugs and ADRs that previously unknown were detected. Nine studies evaluated the prescribing cascades, including the use of antitussive drugs after ACEI, the prescribing cascades related to drug-induced lower urinary tract symptoms and edema, the prescription cascades of statins, and the prescribing cascade relic.Conclusion:PSSA is a useful method for identifying potential prescribing cascades and mining ADR signals using medical prescription databases, especially suitable for the safety monitoring of long-term medication for chronic diseases and the signal detection of ADR that causal relationships are difficult to determine.

Objective:To explore the reasons for medical treatment delay in patients with sudden hearing loss.Methods:This was a qualitative research. A purposive sampling method was used to select patients with sudden hearing loss who visited the Otolaryngology and Head and Neck Surgery Department at the First Hospital of Shanxi Medical University from January to March 2024. Data were collected through face-to-face, semi-structured interviews and analyzed using Colaizzi's 7-step method.Results:A total of 23 participants were interviewed, aged 19 to 72 years; six were male, and 17 were female. A total of four main themes and nine sub-themes were identified: insufficient disease awareness (lack of symptom related knowledge, rational attribution of symptoms, lack of symptom management ability) , physical and psychological perception differences, and negative emotional experiences (conflict with existing roles, negative emotional experiences) , socio-economic factors (insufficient social support, economic burden) , and limitations of medical services and resources (limitations in the diagnostic and treatment capabilities of primary healthcare institutions, insufficient medical resources) .Conclusions:The reasons for medical treatment delay in patients with sudden hearing loss are diverse. Healthcare providers can implement targeted interventions to help patients establish correct medical awareness, reducing the delay in seeking treatment.

This paper focuses on the application of health big data in cancer screening. Firstly, the sources and characteristics of health big data are introduced, then the commonly used epidemiological designs and analytical techniques in hospital-based cancer screening studies are summarized and the application scenarios of such studies are described. Finally, the challenges and future development in the application of health big data are analyzed to provide reference for the future studies.

Objective:To analyze the effect of influenza vaccination on influenza cluster epidemic in primary and secondary schools in Beijing during the 2023-2024 surveillance season and provide evidence for the improvement of influenza vaccination strategies.Methods:The incidence data of influenza cluster epidemic and influenza vaccination coverage in the schools in Beijing during 2023-2024 were collected. Descriptive epidemiological methods were used to analyze cluster epidemic characteristics, and χ2 test was used to compare incidence differences between groups, and OR value and vaccine effectiveness [VE=(1- OR)×100%] were calculated. A negative binomial regression model was used to evaluate the association between school vaccination rates and cluster epidemic risk. Joinpoint regression was used to analyze trends in relative risk ( RR) with increasing vaccination coverage and to determine the optimal vaccination threshold. Results:A total of 126 influenza cluster epidemic were reported in 115 primary and secondary schools in Beijing during 2023-2024 with the median size of 15 case, the average attack rate was 36.26% (2 033/5 607). The epidemics mainly occurred in urban area (70, 55.56%). Primary schools were the main setting (78, 61.90%), and influenza A(H3N2) was the predominant subtype (108, 85.71%). The overall influenza vaccination coverage in the primary and secondary students was 54.26%, while the average vaccination in classes affected by the epidemics was 58.57%. The overall protection rate was 47.62%, the protection rate was higher in primary schools (49.65%) than in secondary schools (46.60%). The protection rates against influenza A(H1N1)pdm09 (80.93%) and influenza B (Victoria lineage) (81.65%) were significantly higher than that against influenza A(H3N2) (44.19%). When school vaccination coverage reached ≥76.00%, the epidemic risk decreased by 52.82%.Conclusions:Even the match between influenza vaccine strains and circulating strains is suboptimal, increasing influenza vaccination coverage in schools can effectively reduce the risk for influenza cluster epidemic. In the future, measures such as policy guidance and public health education should be taken to further improve vaccination coverage, thereby establishing herd immunity and reducing the transmission risk of influenza in schools.