Objective : To construct a human keratinocyte-forming cell line(HaCaT) with stable knockout of the G protein-coupled receptor 107(GPR107) gene, and to preliminarily investigate the effect of GPR107 deletion on the biological behaviour of HaCaT cells. Methods : Using CRISPR/Cas9 gene editing technology, HaCaT cells with knockout ofGPR107gene were constructed and monoclonal cells with GPR107 deletion were obtained by limited dilution method. Genomic DNA was amplified using Western blot and PCR and sequenced to validate the single-cell clones with knockdown of GPR107. The cell cycle changes were detected by flow cytometry; cell proliferation was detected by CCK-8; apoptosis was detected by flow cytometry; changes in cell differentiation markers were detected by Western blot; cell migration ability was analyzed by cell scratch assay and other methods. Results : LentiCas9-Blast and plenti-guide-RNA-GPR107 plasmids were successfully transfected into HaCaT cells, 21 monoclonal cell lines were obtained by limited dilution, and Western blot showed that the GPR107 expression was significantly reduced in 8 of them; PCR sequencing of the cellular genome was used, which resulted in the obtainment of C4 and 2D8GPR107-/-HaCaT monoclonal cell lines. CCK-8 assay and flow cytometry assay showed thatGPR107gene deletion resulted in G0G1phase block, significantly weakened proliferation ability and increased apoptosis level of HaCaT cells. Western blot found that the differentiation of HaCaT cells accelerated after knockdown ofGPR107. Additionally the results of the cell scratch assay indicated that the migration ability of HaCaT cells was enhanced after knockdown ofGPR107. The results showed that the migration ability of HaCaT cells was enhanced after knockdown ofGPR107. Conclusion HaCaT cell line withGPR107gene deletion is successfully constructed, GPR107 deletion blocks the G0G1phase of HaCaT cells, which inhibiting the proliferation of HaCaT cells and promoted apoptosis, and it was found that the differentiation and migration of HaCaT cells were enhanced after knocking downGPR107.

OBJECTIVE To investigate the result of human immunodeficiency virus(HIV)screening for the people visiting to a three-A hospital of Sichuan Province and analyze the prevalence of complications with hepatitis B virus(HBV)infection,hepatitis C virus(HCV)infection and Treponema pallidum(TP)infection in the emerging HIV infection patients.METHODS The result of HIV screening for the people who visited to Ziyang Central Hos-pital from Jan.1,2020 to Dec.31,2024 and the test results of HBV,HCV and TP for the emerging HIV infec-tion patients were collected and were summarized and statistically analyzed by SPSS.0 software.RESULTS Totally 289 891 case-times were tested for HIV,1529 cases were previously diagnosed with HIV,465 of whom were tested posi-tive for the first time,there was significant difference in the positive rate of test for the first time among the 5 years(x2=15.998,P=0.003).Totally 353 cases were confirmed positive among the 465 primary positive screening cases.Among the emerging HIV infection patients,the positive rate was higher in the male than in the female(x2=141.141,P＜0.001),and the positive rate was high among the population aged more than 40 year old(x2=11.448,P＜0.001),mi-grant workers(x2=270.110,P＜0.001)and low education level population(x2=25.911,P＜0.001).The detection rate of gp41 was up to 100.00％in strip type testing.The analysis of the ratio of relative light unit(RLU)to Cutoff val-ue(COI)in the initial screening experiment showed that when COI was greater than 50,all of the confirmed tests were positive,when COI ranged between 1 and 5,the false positive rate was 97.06％.The incidence of complica-tion with HBV infection in the emerging HIV infection patients was increased year by year(x2=20.355,P＜0.001),and the incidence of complication with HCV infection was increased in recent two years(x2=10.690,P=0.030).CONCLUSIONS There is no obvious rise of positive rate of HIV screening among the people visiting to the hospital in recent 5 years.The sensitivity of the primary screening of clinical laboratory is high without posi-tive missing test.The positive rates of HBV and HCV are increased among the emerging HIV infection patients.

ObjectiveObesity has been identified as one of the most important risk factors for cognitive dysfunction. Physical exercise can ameliorate learning and memory deficits by reversing synaptic plasticity in the hippocampus and cortex in diseases such as Alzheimer’s disease. In this study, we aimed to determine whether 8 weeks of treadmill exercise could alleviate hippocampus-dependent memory impairment in high-fat diet-induced obese mice and investigate the potential mechanisms involved. MethodsA total of sixty 6-week-old male C57BL/6 mice, weighing between 20-30 g, were randomly assigned to 3 distinct groups, each consisting of 20 mice. The groups were designated as follows: control (CON), high-fat diet (HFD), and high-fat diet with exercise (HFD-Ex). Prior to the initiation of the treadmill exercise protocol, the HFD and HFD-Ex groups were fed a high-fat diet (60% fat by kcal) for 20 weeks. The mice in the HFD-Ex group underwent treadmill exercise at a speed of 8 m/min for the first 10 min, followed by 12 m/min for the subsequent 50 min, totally 60 min of exercise at a 0° slope, 5 d per week, for 8 weeks. We employed Y-maze and novel object recognition tests to assess hippocampus-dependent memory and utilized immunofluorescence, Western blot, Golgi staining, and ELISA to analyze axon length, dendritic complexity, number of spines, the expression of c-fos, doublecortin (DCX), postsynaptic density-95 (PSD95), synaptophysin (Syn), interleukin-1β (IL-1β), and the number of major histocompatibility complex II (MHC-II) positive cells. ResultsMice with HFD-induced obesity exhibit hippocampus-dependent memory impairment, and treadmill exercise can prevent memory decline in these mice. The expression of DCX was significantly decreased in the HFD-induced obese mice compared to the control group (P<0.001). Treadmill exercise increased the expression of c-fos (P<0.001) and DCX (P=0.001) in the hippocampus of the HFD-induced obese mice. The axon length (P<0.001), dendritic complexity (P<0.001), the number of spines (P<0.001) and the expression of PSD95 (P<0.001) in the hippocampus were significantly decreased in the HFD-induced obese mice compared to the control group. Treadmill exercise increased the axon length (P=0.002), dendritic complexity(P<0.001), the number of spines (P<0.001) and the expression of PSD95 (P=0.001) of the hippocampus in the HFD-induced obese mice. Our study found a significant increase in MHC-II positive cells (P<0.001) and the concentration of IL-1β (P<0.001) in the hippocampus of HFD-induced obese mice compared to the control group. Treadmill exercise was found to reduce the number of MHC-II positive cells (P<0.001) and the concentration of IL-1β (P<0.001) in the hippocampus of obese mice induced by a HFD. ConclusionTreadmill exercise led to enhanced neurogenesis and neuroplasticity by increasing the axon length, dendritic complexity, dendritic spine numbers, and the expression of PSD95 and DCX, decreasing the number of MHC-II positive cells and neuroinflammation in HFD-induced obese mice. Therefore, we speculate that exercise may serve as a non-pharmacologic method that protects against HFD-induced hippocampus-dependent memory dysfunction by enhancing neuroplasticity and neurogenesis in the hippocampus of obese mice.

Body weight abnormalities, including overweight, obesity, and underweight, have become a dual public health challenge in Chinese adults: overweight and obesity lead to a variety of chronic complications, while underweight increases the risks of malnutrition, sarcopenia, and organ dysfunction. To systematically address these issues, multidisciplinary experts in endocrinology, sports science, nutrition, and psychiatry from various regions have held multiple weight management seminars. Based on the latest epidemiological data and clinical evidence, they expanded the guideline to include assessment and intervention strategies for underweight, in addition to the core content of obesity management. This guideline outlines the etiological mechanisms, evaluation methods, and multidimensional management strategies for overweight and obesity, covering key areas such as diagnosis and assessment, medical nutrition therapy, exercise prescription, pharmacological intervention, and psychological support. It is intended to provide a scientific and standardized approach to weight management across the adult population, aiming to curb the rising prevalence of obesity, mitigate complications associated with abnormal body weight, and improve nutritional status and overall quality of life.

The integration of science and education is not only an important strategy for promoting social progress and technological development,but also a modern form of higher education aiming at cultivating innovative talents.Conducting scientific research training for undergraduate medical students is one of the important ways to cultivate their innovative abilities and comprehensive qualities.Our team proposed a"teaching,science,and ideology trinity"teaching model to comprehensively cultivate students' scientific research comprehensive abilities under the value orientation of ideological and political education by or-ganically integrating molecular biology experimental teaching with the scientific research training of under-graduate medical students.In this teaching activity,taking the experiment of gene polymorphism as an example,our team selected students with research potential from the whole grade and divided them into 4 project groups that were instructed by 4 teachers.The students were trained in the whole process of scien-tific research,including topic selection,project writing,experimental designing,application for research ethics,and project summary.Our team has always adhered to student-contentedness of educational con-cepts to stimulate students' intrinsic motivation throughout the teaching process.Students are the design-ers and implementers of the project,and teachers are only guides and promoters of learning.After this training,students not only became familiar with the writing and implementation of scientific research pro-jects,but also improved their literature reading,experimental designing,experimental skills,and prob-lem-solving abilities.More importantly,this teaching activity also cultivated students' awareness of re-search ethics and academic moral standards.

Objective To analyze differences of purified water,softened water,and concentrated softened water on the decontamination effects for surgical instruments,so as to provide a reliable reference for the selection of cleaning water for surgical instruments.Methods The physical and chemical indexes and components of concentrated softened water,softened water,and purified water were detected,and their cleaning effects for instrument were compared.The decontamination cleaning experiment was conducted in three hospitals with different types of cleaning water using mini cleaning machines,and the differences in the decontamination time were analyzed.The cleaning and decontamination experiments on contaminated instruments was performed using a spray cleaning and disinfection device,and the cleaning effects of instruments with different types of cleaning water were analyzed.Results Calcium content and hardness of the three types of cleaning water were all at a low level,which can avoid scale adhesion for cleaning surgical instruments.There were statistically significant differences in the pH value,conductivity,and contents of calcium,sodium and chloride among the three cleaning waters(P<0.05).The purified water was weakly acidic,and its conductivity,hardness,and contents of calcium,sodium and chloride were all at low levels.The softened water and concentrated softened water were weakly alkaline,with high levels of conductivity and sodium content and low level of chloride.There were statistically significant differences in the decontamination time of the purified water,softened water and concentrated softened water among hospitals(P<0.05).Under the same contamination condition of surgical instruments,there was a statistically significant difference in the qualified rate of instruments cleaning in the upper and lower cleaning baskets with different cleaning waters(P<0.05).Conclusion Concentrated softened water and softened water have high sodium content,and their decontamination and cleaning abilities are significantly stronger than those of the purified water.Purified water has poorer effects in instruments cleaning for its deionized property.Using concentrated softened water or softened water in the surgical instrument cleaning process can achieve effects of reducing consumption and increasing efficiency,which is conducive to improving cleaning efficiency and quality.

The integration of science and education is not only an important strategy for promoting social progress and technological development,but also a modern form of higher education aiming at cultivating innovative talents.Conducting scientific research training for undergraduate medical students is one of the important ways to cultivate their innovative abilities and comprehensive qualities.Our team proposed a"teaching,science,and ideology trinity"teaching model to comprehensively cultivate students' scientific research comprehensive abilities under the value orientation of ideological and political education by or-ganically integrating molecular biology experimental teaching with the scientific research training of under-graduate medical students.In this teaching activity,taking the experiment of gene polymorphism as an example,our team selected students with research potential from the whole grade and divided them into 4 project groups that were instructed by 4 teachers.The students were trained in the whole process of scien-tific research,including topic selection,project writing,experimental designing,application for research ethics,and project summary.Our team has always adhered to student-contentedness of educational con-cepts to stimulate students' intrinsic motivation throughout the teaching process.Students are the design-ers and implementers of the project,and teachers are only guides and promoters of learning.After this training,students not only became familiar with the writing and implementation of scientific research pro-jects,but also improved their literature reading,experimental designing,experimental skills,and prob-lem-solving abilities.More importantly,this teaching activity also cultivated students' awareness of re-search ethics and academic moral standards.

Atherosclerosis is an arterial lesion involving abnor-mal lipid metabolism and an inflammatory response,and is the initiating factor of many cardiovascular and cerebrovascular dis-eases.Glycosylated ceramides are derivatives of ceramide mole-cules with a glycosylated group attached,which not only affect the structural integrity of cell membranes,but also regulate apop-tosis,inflammation and lipid metabolism,and disorders of glyco-sylated ceramide metabolism are closely related to the occurrence and progression of atherosclerosis.This review focuses on the specific functions of the glycosylated ceramide-related metabolic enzymes glucose ceramide synthetase,glucosylceramide syn-thetase,lactose ceramide synthetase,and galactosidase in athero-sclerosis,as well as their important effects on the development of atherosclerosis.Targeted therapeutic strategies for these meta-bolic enzymes,related drug development and significant potential in atherosclerosis prevention and treatment are also reviewed.

This study was aimed at identifying the pathogenic bacteria responsible for the death of a young tiger at the Fujian Meihua Mountain South China Tiger Breeding Research Institute.Tissue samples from the lungs,liver,and intestines of the deceased tiger were collected,and the bacteria were cultured inasterile environment.The bacterial strains were characterized according to their morphological and molecular biological properties,including assessment of virulence genes and antibiotic resistance genes,mouse lethality tests,and antibiotic susceptibility evaluations.A predominant bacterial strain isolated from the liver of the deceased tiger was identified as enterotoxigenic Escherichia coli(ETEC)strain Tiger22513F.Phylogenetic analysis of the 16S rRNA gene revealed that the Tiger22513F strain exhibited close genetic similarity to the reference strain ETEC(MF919609.1),with 99.9%nucleotide similarity,and resided on the same evolutionary branch.The Tiger22513F strain contained 11 antibiotic resistance genes(tetA,sul1,sul3,cmlA,floR,blaTEM,blaSHV,blaCMY-2,qnrA,qnrS,and qnrD)along with five virulence genes(VT1,fyuA,tsh,iucD,and ST).Mouse lethality tests indicated significant pathogenicity toward mice,affecting primarily the lungs,liver,and intestines.Antibiotic susceptibility testing demonstrated that this strain exhibited resistance to various classes of beta-lactam antibiotics,as well as quinolones and aminoglycosides.This investigation successfully isolated a multi-drug resistant enterotoxigenic Escherichia coli strain with pronounced pathogenicity from the liver of a deceased tiger;thus providing valuable scientific insights for clinical diagnosis,as well as prevention and control measures,against ETEC infections in South China tigers.

BackgroundWith the rapid development of the networking technologies， internet addiction has increasingly become a serious mental health issue. Previous studies have revealed the link between childhood trauma and internet addiction， while the mediating role of perceived stress in this link is not yet clear. ObjectiveTo investigate the role of medical students' perceived stress in the relationship between childhood trauma and internet addiction， so as to provide references for the intervention of internet addiction. MethodsFrom February to March 2023， a random sampling technique was used to select 1 232 undergraduate students from the School of Clinical Medical Sciences of Southwest Medical University as research subjects. The Childhood Trauma Questionnaire-Short Form （CTQ-SF）， Perceived Stress Scale （PSS）， Internet Gaming Disorder Scale （IGDS）， and Bergen Social Media Addiction Scale （BSMAS） were used for assessment. Pearson's correlation coefficients were calculated. The mediation effect of perceived stress in the relationship between childhood trauma and internet addiction was tested using Model 4 in the SPSS Process 4.1， and Bootstrapping procedure involving 5 000 replicates was employed to confirm the statistical significance. ResultsA total of 1 016 （82.47%） valid completed questionnaires were gathered. The CTQ-SF scores of medical students were positively correlated with PSS scores， IGD scores， and BSMAS scores （r=0.583， 0.474， 0.465， P<0.01）. PSS scores were positively correlated with IGD scores and BSMAS scores （r=0.369， 0.479， P<0.01）. Childhood trauma in medical students was found to positively predict perceived stress （β=0.191， P<0.01）， social media addiction （β=0.160， P<0.01）， and internet gaming disorder （β=0.106， P<0.01）. Perceived stress played a significant mediating role in the relationship between childhood trauma and internet gaming disorder， indirect effect value was 0.018 （95% CI： 0.009~0.027）， accounting for 16.98%. Perceived stress also exhibited a significant mediating role in the relationship between childhood trauma and social media addiction， indirect effect value was 0.063 （95% CI： 0.048~0.079）， accounting for 39.38%. ConclusionChildhood trauma in medical students may affect internet gaming disorder and social media addiction through perceived stress. ［Funded by 2022 Annual Research Project of Sichuan Applied Psychology Research Center，（number，CSXL-22102）］