AIM:To investigate the mechanism of reduced tear secretion in depression-related dry eye rats based on 5-HT/TRPV4/AQP5.METHODS:Healthy SD male rats were established with chronic unpredictable mild stress(CUMS)method to establish a depression-induced dry eye model(n=8), and the control group was blank rats(n=8). The ELISA method was used to compare the 5-hydroxytryptamine(5-HT)in serum and hippocampal tissue of the two groups, and the HE sections of lacrimal gland and AQP5 immunohistochemistry were observed. Western blot and RT-PCR were used to detect the expression of 5-HT3R, TRPV4 and AQP5 in the lacrimal gland tissue of the two groups of rats.RESULTS:The tear secretion in the depression-induced group was significantly reduced(P=0.001), the serum and hippocampal 5-HT levels were significantly reduced(all P<0.05), the expression of AQP5 antibody in the lacrimal gland immunohistochemistry was significantly lower than that in the control group(P<0.001), the expression of 5-HT3R, TRPV4 and AQP5 in the lacrimal gland was significantly reduced(all P<0.05), and no obvious inflammatory cells were found in the lacrimal gland tissue sections.CONCLUSION:Depression-related dry eye may occur through a non-inflammatory 5-HT/TRPV4/AQP5 mechanism.

AIM:To investigate the mechanism of reduced tear secretion in depression-related dry eye rats based on 5-HT/TRPV4/AQP5.METHODS:Healthy SD male rats were established with chronic unpredictable mild stress(CUMS)method to establish a depression-induced dry eye model(n=8), and the control group was blank rats(n=8). The ELISA method was used to compare the 5-hydroxytryptamine(5-HT)in serum and hippocampal tissue of the two groups, and the HE sections of lacrimal gland and AQP5 immunohistochemistry were observed. Western blot and RT-PCR were used to detect the expression of 5-HT3R, TRPV4 and AQP5 in the lacrimal gland tissue of the two groups of rats.RESULTS:The tear secretion in the depression-induced group was significantly reduced(P=0.001), the serum and hippocampal 5-HT levels were significantly reduced(all P<0.05), the expression of AQP5 antibody in the lacrimal gland immunohistochemistry was significantly lower than that in the control group(P<0.001), the expression of 5-HT3R, TRPV4 and AQP5 in the lacrimal gland was significantly reduced(all P<0.05), and no obvious inflammatory cells were found in the lacrimal gland tissue sections.CONCLUSION:Depression-related dry eye may occur through a non-inflammatory 5-HT/TRPV4/AQP5 mechanism.

[Objective] To investigate the molecular prevalence and genotype of human parvovirus B19(B19) among blood donors in Lanzhou, and provide data support for monitoring the positive rate of B19 DNA in local blood donors. [Methods] A total of 7 644 blood donor samples collected from January to September 2022 were randomly screened using real-time fluorescent PCR, resulting in 23 samples testing positive for B19 DNA. The characteristics of the B19 DNA reactive donors including gender, age, blood donation recruitment and promotion mode, and donation frequency were analyzed using SPSS 22.0. Additionally, the VP1 gene fragment of B19 DNA reactive samples was sequenced and an evolutionary tree was constructed by the N-J method. [Results] The results showed that the positive rate of B19 DNA in Lanzhou was 0.30%, and the positive population mainly consisted of female individuals aged 18-30 years old who were first-time blood donors; furthermore, genotype 1a was identified as predominant. [Conclusion] The positive rate of B19 DNA is low among blood donors in Lanzhou, with genotype 1a being predominant. It is recommended to periodically monitor the B19 prevalence in blood donors and enhance prevention and control measures, thus improving blood quality and safety.

Objective: To understand current state of physical health levels of first year students in different body mass index (BMI) categories in Ningxia universities, and to explore the correlation between BMI and physical fitness index (PFI), so as to provide a reference for enhancing physical health levels of university students. Methods: In November 2024, physical fitness test data from 16 631 first year students across four universities in Yinchuan City, Ningxia from 2019 to 2023 were collected by adopting convenience and stratified cluster random sampling methods. The PFI was calculated using the Z score of the physical fitness test results, and a nonlinear quadratic model was established via least squares regression to examine the relationship between BMI and PFI among university students. Results: The BMI for males was (21.69±3.53)kg/m 2, while for females was (20.78±2.94)kg/m 2. The composite score for males physical fitness (69.86±9.25) was lower than that for females (72.24± 8.15 ), with a statistically significant difference ( t =-17.54, P <0.01). Moreover, the failure rates of various physical fitness indicators (vital capacity, sit and reach, standing long jump, pull ups/1 minute sit ups, 1 000 m/800 m run) were higher among males than females ( χ 2=103.48, 72.45, 14.38, 5 134.85, 188.89, all P <0.01). Comparisons across BMI categories revealed that among males, the normal weight group outperformed other groups in the 50 m sprint, standing long jump, 1 000 m sprint, composite score, and PFI ( F =89.17, 113.90, 179.02, 573.35, 593.08); among female students, the normal weight group outperformed other groups in the 50 m sprint, sit and reach, 800 m run, composite score, and PFI ( F =10.67, 19.58 , 96.45, 294.05, 183.45) (all P <0.01). The relationship between BMI and PFI among first year students exhibited a parabolic change trend, students with a moderate BMI demonstrated higher PFI, and as BMI increased, PFI decreased (all P <0.01). Conclusions The physical health level of male students in Ningxia universities is lower than that of female students. There is a correlation between BMI classification and PFI. Tailored intervention measures should be implemented according to the physical characteristics of students across different genders and BMI classifications to enhance university students physical health.

Elderly stroke patients generally have restricted life space,which increases the incidence of falls,weakness,and dementia,reduces their quality of life,and ultimately leads to an increase in readmission and mortality rates.This article mainly introduces the concept,theoretical model and measuring tools of life space.The level and influencing factors of life space in elderly stroke patients were reviewed in order to provide references for medical staff to carry out relevant research and formulate targeted intervention programs about life space for elderly stroke patients.

Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-positive bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-positive bacteria from blood cultures in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:A total of 3 163 strains of Gram-positive pathogens were collected from 51 member units，and the top five bacteria were Staphylococcus aureus（ n=1 147，36.3%），coagulase-negative Staphylococci（ n=928，29.3%）， Enterococcus faecalis（ n=369，11.7%）， Enterococcus faecium（ n=296，9.4%）and alpha-hemolyticus Streptococci（ n=192，6.1%）. The detection rates of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）were 26.4%（303/1 147）and 66.7%（619/928），respectively. No glycopeptide and daptomycin-resistant Staphylococci were detected. The sensitivity rates of Staphylococcus aureus to cefpirome，rifampin，compound sulfamethoxazole，linezolid，minocycline and tigecycline were all >95.0%. Enterococcus faecium was more prevalent than Enterococcus faecalis. The resistance rates of Enterococcus faecium to vancomycin and teicoplanin were both 0.5%（2/369），and no vancomycin-resistant Enterococcus faecium was detected. The detection rate of MRSA in southern China was significantly lower than that in other regions（ χ2=14.578， P=0.002），while the detection rate of MRCNS in northern China was significantly higher than that in other regions（ χ2=15.195， P=0.002）. The detection rates of MRSA and MRCNS in provincial hospitals were higher than those in municipal hospitals（ χ2=13.519 and 12.136， P<0.001）. The detection rates of MRSA and MRCNS in economically more advanced regions（per capita GDP≥92 059 Yuan in 2022）were higher than those in economically less advanced regions（per capita GDP<92 059 Yuan）（ χ2=9.969 and 7.606， P=0.002和0.006）. Conclusions:Among the Gram-positive pathogens causing bloodstream infections in China， Staphylococci is the most common while the MRSA incidence decreases continuously with time；the detection rate of Enterococcus faecium exceeds that of Enterococcus faecalis. The overall prevalence of vancomycin-resistant Enterococci is still at a low level. The composition ratio of Gram-positive pathogens and resistant profiles varies slightly across regions of China，with the prevalence of MRSA and MRCNS being more pronounced in provincial hospitals and areas with a per capita GDP≥92 059 yuan.

Objective:To explore the risk factors and treatments of portal vein thrombosis (PVT) in children after pediatric living donor liver transplantation (pLDLT) .Method:From January 2014 to December 2021, the relevant clinical data were retrospectively reviewed for 975 LDLT children at Department of Pediatric Organ Transplantation of Tianjin First Central Hospital. Based upon the postoperative occurrence of PVT, they were assigned into two groups of PVT (19 cases) and non-PVT (956 cases). Univariate and multivariate analyses were performed for screening the risk factors of PVT post-LDLT and discussing the managements and prognoses of PVT.Result:Among them, overall incidence of PVT post-LDLT was 1.9% (19/975), and median time for an initial occurrence of PVT 8 (1-495) day. Single-factor analysis indicated that donor height ( P=0.014), operative duration ( P=0.002) and vascular interposition ( P=0.001) were correlated with the occurrence of postoperative PVT post-pLDLT. Multifactorial analysis revealed that operative duration ( P=0.008) and vascular interposition ( P<0.01) were independent risk factors for PVT post-pLDLT. For 19 cases of postoperative PVT, the measures included surgical thrombectomy (8 cases), urokinase thrombolysis plus warfarin anticoagulation (3 cases), interventional treatment (3 cases), warfarin anticoagulation (4 cases) and retransplantation (1 cases). After treatment, the outcomes were a disappearance of PVT (15 cases), symptomatic improvement (2 cases) and unrelated mortality (2 cases) . Conclusion:During pLDLT, intraoperative placement of blood vessels and operative duration are independent risk factors for the occurrence of PVT. Timely standardized treatment may achieve satisfactory therapeutic outcomes.

Alzheimer's disease (AD) is a common and highly disabling irreversible degenerative disease of the central nervous system, with characteristics as progressive cognitive impairment, memory loss, and behavioral disturbances. Cognitive impairment in AD, being closely associated with amyloid beta-protein (Aβ) deposition, Tau hyperphosphorylation and neuroinflammation, affects the quality of life of patients. Currently, the exact cause of AD remains unclear, and effective treatment options still lacks. In recent years, stem cell-derived exosomes have garnered widespread attention due to their unique biological properties and crucial role in intercellular communication. These exosomes can carry various bioactive molecules, such as proteins, lipids, and RNA, playing significant roles in central nervous system degenerative diseases. Therefore, this article primarily describes the biogenesis, biological characteristics, and advantages of stem cell-derived exosomes, and summarizes their current applications and future prospects in cognitive impairment in AD, aiming to provide new insights for AD treatment.

Objective To examine the protective effect and mechanism of formononetin on rat cardiomyocyte injury induced by hy-poxia/reoxygenation.Methods The H9C2 rat cardiomyocytes were randomly divided into the control group,hypoxia/reoxygenation group,and formononetin group.Cells in the control group were cultured in conventional incubators,and cells in the hypoxia/reoxygenation group were cultured in hypoxia incubators and conventional incubators alternately.Cells in the formononetin group were treated with 35μmol/L formononetin after incubation in the hypoxia/reoxygenation.Cell activity was tested by a cell activity detection kit.The content of oxidative stress and inflammatory response indicators were examined by related test kits.The flow cytometry and polynucleotide chain break detection technology were used to detect apoptosis levels.Western blot was used to detect the levels of apoptosis-related proteins.Results Compared with the control group,cells in the hypoxia/reoxygenation group showed decreased cell activity and increased oxida-tive stress,inflammatory damage,and apoptosis(P＜0.05).Compared with the hypoxia/reoxygenation group,cells of the formononetin group showed increased cell activity and decreased oxidative stress,inflammatory damage,and apoptosis(P＜0.05).Conclusion For-mononetin may protect against hypoxia/reoxygenation injury by reducing the apoptosis of H9C2 rat cardiomyocytes.

The complex pathological mechanism of dry eye involves multiple pathways, such as immunity and inflammation, and requires an integral research program to control the whole picture. Various histological techniques can elucidate the complex physio-pathological state of organisms from a holistic and global perspective, thus providing more comprehensive biological information. Mass spectrometry can sensitively detect the changes of protein content in tear samples, providing convenience for proteomics research of dry eye. At present, proteomics has demonstrated its application in the identification of dry eye types, severity grading, and therapeutic effect evaluation. In addition, proteomics combined with metabolomics and microbiomics can more comprehensively explain the pathogenesis of dry eye. In the future, proteomics is expected to provide more powerful support for the precise diagnosis and treatment of dry eye, taking an advantage in targeted therapy.