Objective:To understand the contract renewal willingness and its influencing factors among rural order-oriented medical students in Shaanxi Province. M ethods This study employed an explanatory sequential mixed methods design to examine contract renewal patterns among rural order-oriented medical graduates. From February to July 2024, a questionnaire survey was conducted among rural order-oriented medical students who graduated from 2015 to 2023 in Shaanxi Province. The participants were first stratified into three strata based on their year of graduation and stage of service, and one-third of each stratum was randomly selected as the research subjects. Univariate and multivariate analysis methods were used to explore the influencing factors of their willingness to renew their service in rural areas. Secondly, qualitative research methods were employed to conduct thematic interviews with 36 targeted medical students on the influencing factors of their willingness to renew their service. Results:A total of 513 valid questionnaires were collected during the quantitative research phase, including 224 males and 289 females. Of these, 14 were from the 2015-2017 cohort, 247 from the 2018-2020 cohort, and 252 from the 2021-2023 cohort. The results showed that only 30.4%(156/513) of the orientation medical students were willing to practice in primary care after the period of service. Univariate analysis showed that there were six factors related to the willingness to renew the contract, the consistency of the source and implementation of the contract, the completion of the standardized training of residents, the satisfaction with primary work, professional identity, the ability of primary diagnosis and treatment, and the training system and the suitability of primary work. Multivariate analysis showed that the willingness to renew the contract was significantly higher in the students who had the same place of origin and the place of performance( OR=1.7, 95% CI: 1.1-2.6, P=0.022). The willingness to renew the contract was significantly higher among students who participated in the standardized residency training than those who completed the training( OR=2.0, 95% CI: 1.3-3.0, P=0.003), and students with a better fit between the training system and working in primary care were more likely to renew their contract( OR=4.1, 95% CI: 2.8-6.0, P<0.001). Four themes were extracted from the interview: subjective factors, objective environment, policy factors and other factors. Conclusions:The study shows that improving the consistency of the source of students and the implementation of the contract, strengthening the standardized training of residents, and optimizing the adaptation of the training system to the primary work are the key measures to improve the willingness of directional medical students to renew their contract at the primary level.

The specific mechanisms of interferon regulatory factor 8(IRF8)in porcine intestinal in-nate immunity and resistance to enteric virus infection remain to be elucidated.To investigate the immunoregulatory role of IRF8,establishing an IRF8 gene knockout porcine intestinal epithelial cell(IPEC-J2)monoclonal cell line is of significant importance.This study initially aimed to obtain recombinant adeno-associated virus rAAV-sgIRF8-eGFP capable of knocking out the IRF8 gene through co-transfection of HEK-293T cells with three plasmids.Subsequently,IPEC-J2 cells were infected with the virus,and those expressing eGFP were selected by flow cytometry and cultured to form monoclonal cell lines.These cell lines were then identified by Sanger sequencing and West-ern blot techniques.Lastly,qPCR analysis was used to measure the expression levels of interferon factors IFN-α,IFN-β,IFN-γ and IFN-λ,providing preliminary insights into the impact of IRF8 gene knockout on IPEC-J2 cell immunity.The results demonstrated successful generation of rAAV-sgIRF8-eGFP,which successfully infected IPEC-J2 cells leading to eGFP fluorescence.Flow cytometry followed by cell culture led to the establishment of two monoclonal cell lines,IRF8-KO1 and IRF8-KO3.Sanger sequencing revealed a five-base deletion in IRF8-KO1 and a seven-base dele-tion in IRF8-KO3.Western blot confirmed the absence of IRF8 protein expression in IRF8-KO1,making it an ideal candidate monoclonal cell line.qPCR analysis of interferon factors indicated sig-nificant decrease in IFN-γ(P＜0.05)and IFN-λ(P＜0.01)transcription level in IRF8-knockout cells,while the transcription levels of IFN-α and IFN-β remained relatively unchanged.This study successfully established an IRF8 gene knockout IPEC-J2 monoclonal cell line,providing a founda-tion for further research on IRF8-related porcine intestinal immune regulation and mechanisms of intestinal virus infection.

BACKGROUND:Through scientific research addressing the effect of calcined deer antler slices on promoting the proliferation of bone marrow mesenchymal stem cells,it aims to provide empirical support for the integration and innovation of traditional Chinese medicine and modern regenerative medicine,and promote the widespread application of traditional Chinese medicine in the treatment of skeletal system diseases.OBJECTIVE:To investigate the effect of calcined deer antler slices on bone marrow mesenchymal stem cell proliferation.METHODS:Different calcination samples were prepared by wrapping deer antler slices with materials such as clay,yellow clay,and salted yellow clay,resulting in seven different samples(clay-cotton cloth,yellow clay-cotton cloth,salted yellow clay-cotton cloth,yellow clay-tin foil,salted yellow clay-tin foil,yellow clay-honey roasted,salted yellow clay-honey roasted antler slices).Water-soluble extract content in deer antler slices was determined before and after calcination.CCK-8 assay was used to evaluate the effects of different aqueous extracts of calcined antler slices on the proliferation activity of bone marrow mesenchymal stem cells.RESULTS AND CONCLUSION:(1)Calcination significantly increased the water-soluble extract content of deer antler slices,with the highest content observed in samples treated with yellow clay and honey.(2)Calcined deer antler slices significantly promoted bone marrow mesenchymal stem cell proliferation,among which the yellow clay-honey roasted deer antler slices have the most significant effect on promoting the proliferation of bone marrow mesenchymal stem cells.

BACKGROUND:Steroid-induced osteonecrosis of the femoral head is closely related to ferroptosis in osteoblasts.Deer antler peptide can promote the survival and functional establishment of osteoclasts by inhibiting ferroptosis in osteoblasts,and has the potential to treat steroid-induced osteonecrosis of the femoral head,but its regulatory mechanism of ferroptosis in osteoblasts has not yet been clarified.OBJECTIVE:To investigate the mechanism by which deer antler peptide inhibits dexamethasone-induced ferroptosis in osteoblasts.METHODS:(1)Different concentration gradients of antler peptide and dexamethasone were used to intervene in MC3T3-E1 14 cells,and the cell activity was detected by cell counting kit-8 method to determine the effect concentration of antler peptide and dexamethasone.(2)MC3T3-E1 14 cells treated with dexamethasone(800 μmol/L)were intervened with different concentrations of gradient antler polypeptide,which were then divided into blank control group,dexamethasone group and dexamethasone+antler peptide group.Cell counting kit-8 method was used to calculate the effects of different concentrations of antler polypeptide on the proliferation of MC3T3-E1 14 cells.(3)Glutathione,superoxide dismutase,malondialdehyde,lipid peroxide,cellular iron,and reactive oxygen species levels in the blank control group,dexamethasone group and dexamethasone+antler peptide group were detected using kits.The protein expressions of glutathione peroxidase 4 and solute carrier family 7 member 11 were detected by western blot to verify the pathway by which antler polypeptide inhibits ferroptosis.RESULTS AND CONCIUSION:After cell activity was detected by cell counting kit-8 assay,antler peptide(10 mg/mL)and dexamethasone(800 μmol/L)were selected to treat MC3T3-E1 14 cells for 24 hours in subsequent experiments.After treatment with dexamethasone,malondialdehyde,lipid peroxide,cellular iron and reactive oxygen species levels were all increased(P<0.01),while glutathione content and superoxide dismutase activity were decreased and the protein expression of glutathione peroxidase 4 and solute carrier family 7 member 11 were also decreased(P<0.05-0.01).After antler peptide intervention,the changes in the above indexes were obviously reversed(P<0.05-0.01).To conclude,antler peptide may inhibit ferroptosis in osteoblasts by regulating the glutathione peroxidase 4/solute carrier family 7 member 11 axis,and thereby exert a therapeutic role in steroid-induced osteonecrosis of the femoral head.

BACKGROUND:Osteonecrosis is an orthopedic disease that severely limits joint function,with complex pathogenesis involving multiple risk factors.Cathepsins,as a class of enzymes that play a key role in bone metabolism,are closely related to the proliferation,differentiation of bone cells,and remodeling of the bone matrix.However,previous studies have mostly focused on descriptive analyses,lacking direct evidence of causal relationships.OBJECTIVE:To clarify the potential causal relationship between cathepsins and osteonecrosis and to explore their possible mechanisms by analyzing large-scale sample data from the FinnGen database.METHODS:We obtained osteonecrosis-related data from the FinnGen database,including R9(a total of 359 399 samples:1 385 cases and 358 014 controls)and R10 versions(a total of 392 580 samples:1 543 cases and 391 037 controls).Single nucleotide polymorphisms associated with nine cathepsins(cathepsin B,E,F,G,H,O,S,L2,and Z)were acquired from a previous study(3 301 individuals).Univariate Mendelian randomization,reverse univariate Mendelian randomization,and multivariate Mendelian randomization analyses were conducted using the inverse variance weighted method,MR-Egger method,weighted median method,simple mode method,and weighted mode method.Initially,Mendelian randomization analysis was performed using osteonecrosis data from R9.Additionally,sensitivity analyses were conducted using Cochran's Q test,MR-Egger intercept,MR-PRESSO global test,and leave-one-out analysis to check for horizontal pleiotropy and heterogeneity.Subsequently,a validation analysis study was carried out on the R10 dataset,and a meta-analysis was conducted to combine the two datasets to explore the joint effect.RESULTS AND CONCLUSION:Univariate Mendelian randomization analysis results showed that higher levels of cathepsin B were significantly associated with a reduced risk of osteonecrosis(inverse variance weighted:odds ratio(OR)=0.865,95％confidence interval(CI):0.762-0.982,P=0.025),and no reverse causal relationship was found between the nine cathepsins and osteonecrosis(P＞0.05).These associations were validated by meta-analysis.Multivariate analysis,using the nine cathepsins as covariates,revealed a reverse causal relationship between the levels of cathepsin Band the risk of osteonecrosis(inverse variance weighted:OR=0.8710,95％CI:0.761-0.997,P=0.045),consistent with the results before adjustment.Sensitivity analyses based on heterogeneity and horizontal pleiotropy suggested that the results were relatively robust.This study suggests that there is a causal relationship between high levels of cathepsin B and the reduced risk of osteonecrosis,and it may serve as a biomarker for osteonecrosis,providing new directions and insights for the diagnosis and treatment of osteonecrosis.Although this study is based on data analysis of European populations,these findings have important implications for Chinese biomedical research,especially in understanding disease mechanisms,developing biomarkers,and formulating treatment strategies.They also encourage similar studies conducted on Chinese populations to explore the impact of racial and genetic background differences on the occurrence of osteonecrosis.

The specific mechanisms of interferon regulatory factor 8(IRF8)in porcine intestinal in-nate immunity and resistance to enteric virus infection remain to be elucidated.To investigate the immunoregulatory role of IRF8,establishing an IRF8 gene knockout porcine intestinal epithelial cell(IPEC-J2)monoclonal cell line is of significant importance.This study initially aimed to obtain recombinant adeno-associated virus rAAV-sgIRF8-eGFP capable of knocking out the IRF8 gene through co-transfection of HEK-293T cells with three plasmids.Subsequently,IPEC-J2 cells were infected with the virus,and those expressing eGFP were selected by flow cytometry and cultured to form monoclonal cell lines.These cell lines were then identified by Sanger sequencing and West-ern blot techniques.Lastly,qPCR analysis was used to measure the expression levels of interferon factors IFN-α,IFN-β,IFN-γ and IFN-λ,providing preliminary insights into the impact of IRF8 gene knockout on IPEC-J2 cell immunity.The results demonstrated successful generation of rAAV-sgIRF8-eGFP,which successfully infected IPEC-J2 cells leading to eGFP fluorescence.Flow cytometry followed by cell culture led to the establishment of two monoclonal cell lines,IRF8-KO1 and IRF8-KO3.Sanger sequencing revealed a five-base deletion in IRF8-KO1 and a seven-base dele-tion in IRF8-KO3.Western blot confirmed the absence of IRF8 protein expression in IRF8-KO1,making it an ideal candidate monoclonal cell line.qPCR analysis of interferon factors indicated sig-nificant decrease in IFN-γ(P＜0.05)and IFN-λ(P＜0.01)transcription level in IRF8-knockout cells,while the transcription levels of IFN-α and IFN-β remained relatively unchanged.This study successfully established an IRF8 gene knockout IPEC-J2 monoclonal cell line,providing a founda-tion for further research on IRF8-related porcine intestinal immune regulation and mechanisms of intestinal virus infection.

BACKGROUND:Through scientific research addressing the effect of calcined deer antler slices on promoting the proliferation of bone marrow mesenchymal stem cells,it aims to provide empirical support for the integration and innovation of traditional Chinese medicine and modern regenerative medicine,and promote the widespread application of traditional Chinese medicine in the treatment of skeletal system diseases.OBJECTIVE:To investigate the effect of calcined deer antler slices on bone marrow mesenchymal stem cell proliferation.METHODS:Different calcination samples were prepared by wrapping deer antler slices with materials such as clay,yellow clay,and salted yellow clay,resulting in seven different samples(clay-cotton cloth,yellow clay-cotton cloth,salted yellow clay-cotton cloth,yellow clay-tin foil,salted yellow clay-tin foil,yellow clay-honey roasted,salted yellow clay-honey roasted antler slices).Water-soluble extract content in deer antler slices was determined before and after calcination.CCK-8 assay was used to evaluate the effects of different aqueous extracts of calcined antler slices on the proliferation activity of bone marrow mesenchymal stem cells.RESULTS AND CONCLUSION:(1)Calcination significantly increased the water-soluble extract content of deer antler slices,with the highest content observed in samples treated with yellow clay and honey.(2)Calcined deer antler slices significantly promoted bone marrow mesenchymal stem cell proliferation,among which the yellow clay-honey roasted deer antler slices have the most significant effect on promoting the proliferation of bone marrow mesenchymal stem cells.

BACKGROUND:Steroid-induced osteonecrosis of the femoral head is closely related to ferroptosis in osteoblasts.Deer antler peptide can promote the survival and functional establishment of osteoclasts by inhibiting ferroptosis in osteoblasts,and has the potential to treat steroid-induced osteonecrosis of the femoral head,but its regulatory mechanism of ferroptosis in osteoblasts has not yet been clarified.OBJECTIVE:To investigate the mechanism by which deer antler peptide inhibits dexamethasone-induced ferroptosis in osteoblasts.METHODS:(1)Different concentration gradients of antler peptide and dexamethasone were used to intervene in MC3T3-E1 14 cells,and the cell activity was detected by cell counting kit-8 method to determine the effect concentration of antler peptide and dexamethasone.(2)MC3T3-E1 14 cells treated with dexamethasone(800 μmol/L)were intervened with different concentrations of gradient antler polypeptide,which were then divided into blank control group,dexamethasone group and dexamethasone+antler peptide group.Cell counting kit-8 method was used to calculate the effects of different concentrations of antler polypeptide on the proliferation of MC3T3-E1 14 cells.(3)Glutathione,superoxide dismutase,malondialdehyde,lipid peroxide,cellular iron,and reactive oxygen species levels in the blank control group,dexamethasone group and dexamethasone+antler peptide group were detected using kits.The protein expressions of glutathione peroxidase 4 and solute carrier family 7 member 11 were detected by western blot to verify the pathway by which antler polypeptide inhibits ferroptosis.RESULTS AND CONCIUSION:After cell activity was detected by cell counting kit-8 assay,antler peptide(10 mg/mL)and dexamethasone(800 μmol/L)were selected to treat MC3T3-E1 14 cells for 24 hours in subsequent experiments.After treatment with dexamethasone,malondialdehyde,lipid peroxide,cellular iron and reactive oxygen species levels were all increased(P<0.01),while glutathione content and superoxide dismutase activity were decreased and the protein expression of glutathione peroxidase 4 and solute carrier family 7 member 11 were also decreased(P<0.05-0.01).After antler peptide intervention,the changes in the above indexes were obviously reversed(P<0.05-0.01).To conclude,antler peptide may inhibit ferroptosis in osteoblasts by regulating the glutathione peroxidase 4/solute carrier family 7 member 11 axis,and thereby exert a therapeutic role in steroid-induced osteonecrosis of the femoral head.

BACKGROUND:Osteonecrosis is an orthopedic disease that severely limits joint function,with complex pathogenesis involving multiple risk factors.Cathepsins,as a class of enzymes that play a key role in bone metabolism,are closely related to the proliferation,differentiation of bone cells,and remodeling of the bone matrix.However,previous studies have mostly focused on descriptive analyses,lacking direct evidence of causal relationships.OBJECTIVE:To clarify the potential causal relationship between cathepsins and osteonecrosis and to explore their possible mechanisms by analyzing large-scale sample data from the FinnGen database.METHODS:We obtained osteonecrosis-related data from the FinnGen database,including R9(a total of 359 399 samples:1 385 cases and 358 014 controls)and R10 versions(a total of 392 580 samples:1 543 cases and 391 037 controls).Single nucleotide polymorphisms associated with nine cathepsins(cathepsin B,E,F,G,H,O,S,L2,and Z)were acquired from a previous study(3 301 individuals).Univariate Mendelian randomization,reverse univariate Mendelian randomization,and multivariate Mendelian randomization analyses were conducted using the inverse variance weighted method,MR-Egger method,weighted median method,simple mode method,and weighted mode method.Initially,Mendelian randomization analysis was performed using osteonecrosis data from R9.Additionally,sensitivity analyses were conducted using Cochran's Q test,MR-Egger intercept,MR-PRESSO global test,and leave-one-out analysis to check for horizontal pleiotropy and heterogeneity.Subsequently,a validation analysis study was carried out on the R10 dataset,and a meta-analysis was conducted to combine the two datasets to explore the joint effect.RESULTS AND CONCLUSION:Univariate Mendelian randomization analysis results showed that higher levels of cathepsin B were significantly associated with a reduced risk of osteonecrosis(inverse variance weighted:odds ratio(OR)=0.865,95％confidence interval(CI):0.762-0.982,P=0.025),and no reverse causal relationship was found between the nine cathepsins and osteonecrosis(P＞0.05).These associations were validated by meta-analysis.Multivariate analysis,using the nine cathepsins as covariates,revealed a reverse causal relationship between the levels of cathepsin Band the risk of osteonecrosis(inverse variance weighted:OR=0.8710,95％CI:0.761-0.997,P=0.045),consistent with the results before adjustment.Sensitivity analyses based on heterogeneity and horizontal pleiotropy suggested that the results were relatively robust.This study suggests that there is a causal relationship between high levels of cathepsin B and the reduced risk of osteonecrosis,and it may serve as a biomarker for osteonecrosis,providing new directions and insights for the diagnosis and treatment of osteonecrosis.Although this study is based on data analysis of European populations,these findings have important implications for Chinese biomedical research,especially in understanding disease mechanisms,developing biomarkers,and formulating treatment strategies.They also encourage similar studies conducted on Chinese populations to explore the impact of racial and genetic background differences on the occurrence of osteonecrosis.

Objective:To understand the contract renewal willingness and its influencing factors among rural order-oriented medical students in Shaanxi Province. M ethods This study employed an explanatory sequential mixed methods design to examine contract renewal patterns among rural order-oriented medical graduates. From February to July 2024, a questionnaire survey was conducted among rural order-oriented medical students who graduated from 2015 to 2023 in Shaanxi Province. The participants were first stratified into three strata based on their year of graduation and stage of service, and one-third of each stratum was randomly selected as the research subjects. Univariate and multivariate analysis methods were used to explore the influencing factors of their willingness to renew their service in rural areas. Secondly, qualitative research methods were employed to conduct thematic interviews with 36 targeted medical students on the influencing factors of their willingness to renew their service. Results:A total of 513 valid questionnaires were collected during the quantitative research phase, including 224 males and 289 females. Of these, 14 were from the 2015-2017 cohort, 247 from the 2018-2020 cohort, and 252 from the 2021-2023 cohort. The results showed that only 30.4%(156/513) of the orientation medical students were willing to practice in primary care after the period of service. Univariate analysis showed that there were six factors related to the willingness to renew the contract, the consistency of the source and implementation of the contract, the completion of the standardized training of residents, the satisfaction with primary work, professional identity, the ability of primary diagnosis and treatment, and the training system and the suitability of primary work. Multivariate analysis showed that the willingness to renew the contract was significantly higher in the students who had the same place of origin and the place of performance( OR=1.7, 95% CI: 1.1-2.6, P=0.022). The willingness to renew the contract was significantly higher among students who participated in the standardized residency training than those who completed the training( OR=2.0, 95% CI: 1.3-3.0, P=0.003), and students with a better fit between the training system and working in primary care were more likely to renew their contract( OR=4.1, 95% CI: 2.8-6.0, P<0.001). Four themes were extracted from the interview: subjective factors, objective environment, policy factors and other factors. Conclusions:The study shows that improving the consistency of the source of students and the implementation of the contract, strengthening the standardized training of residents, and optimizing the adaptation of the training system to the primary work are the key measures to improve the willingness of directional medical students to renew their contract at the primary level.