BACKGROUND:The mesenchymal stem cell secretome contains bioactive substances,cytokines,and growth factors.Three-dimensional cell culture can regulate the secretion of these components,potentially enhancing the ability to promote injury repair.OBJECTIVE:To investigate the repair effect of three-dimensional cultured human umbilical cord mesenchymal stem cell secretome on skin injuries in mice.METHODS:Human umbilical cord mesenchymal stem cells were cultured in conventional two-dimensional culture dishes and 96-well U-bottom cell culture plates,from which their secretory components were subsequently collected.The expression of skin damage repair related secretory factors in umbilical cord mesenchymal stem cells was analyzed using RT-qPCR.The protein expression level of skin damage repair related factors in umbilical cord mesenchymal stem cell secretome was detected using enzyme-linked immunosorbent assay.The potential of human umbilical cord mesenchymal stem cell secretome to repair vascular injuries was evaluated using an immortalized human umbilical vein endothelial cell migration model.A mouse skin injury model was established,and the human umbilical cord mesenchymal stem cell secretome was injected subcutaneously.Repair effects on skin injury were assessed through wound healing rates and histopathological analysis.RESULTS AND CONCLUSION:(1)After three days of cultivation,human umbilical cord mesenchymal stem cells cultured in two dimensions exhibited a fibroblast-like,swirling growth pattern,whereas three-dimensional culture led to the formation of uniform microspheres.(2)Compared with two-dimensional culture,three-dimensional culture significantly increased the mRNA expression of transforming growth factor β and basic fibroblast growth factor in human umbilical cord mesenchymal stem cells.(3)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly enhanced the protein expression of vascular endothelial growth factor,interleukin-10,and granulocyte-macrophage colony-stimulating factor in the human umbilical cord mesenchymal stem cell secretome.(4)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly promoted the migration of immortalized human umbilical cord mesenchymal stem cells.(5)Compared with the untreated control group and the two-dimensional cultured human umbilical cord mesenchymal stem cell secretome,the three-dimensional cultured human umbilical cord mesenchymal stem cell secretome can significantly accelerate the skin wound healing rate and wound skin structure remodeling in mice.These results indicate that three-dimensional culture can enhance the expression of paracrine factors of human umbilical cord mesenchymal stem cells,and their secretome can significantly promote the repair of mouse skin damage.

ObjectiveTo investigate the molecular mechanism by which Yifei Xuanfei Jiangzhuo prescription regulates the nuclear factor-κB （NF-κB）/NOD-like receptor protein 3 （NLRP3） signaling pathway to improve neuronal function in vascular dementia （VaD） rats. MethodsA VaD model was established by intermittently clamping the bilateral common carotid arteries （CCA） combined with bilateral vascular occlusion （2-VO）. Eighty-four SD rats were randomly divided into a blank group， sham group， model group， piracetam group （0.2 g·kg^-1）， and low-， medium-， and high-dose Yifei Xuanfei Jiangzhuo prescription groups （6.09， 12.18， and 24.36 g·kg^-1）. Drug administration began on day 7 after surgery， once daily for 28 consecutive days. Behavioral experiments were used to evaluate learning and spatial memory. Hematoxylin-eosin （HE） staining was applied to observe pathological morphological changes in the CA1 region of the hippocampus. Transmission electron microscopy was used to examine the ultrastructure of hippocampal neurons. Terminal deoxynucleotidyl transferase dUTP nick end labeling （TUNEL） was used to detect neuronal apoptosis in the CA1 region. Immunohistochemistry was performed to determine the positive expression rate of neuronal nuclear antigen （NeuN）. Immunofluorescence single staining was used to assess nuclear expression of NF-κB p65 in brain tissue. Western blot was used to detect the protein expression levels of inhibitor of κB kinase （IKK）， NF-κB p65， NLRP3， Caspase-1， apoptosis-associated speck-like protein （ASC）， and interleukin-1β （IL-1β）. ResultsCompared with the blank group， the model group showed a significant reduction in platform-crossing frequency （P0.01）， aggravated hippocampal injury， a significant increase in neuronal apoptosis （P0.05）， decreased NeuN positivity in the CA1 region （P0.05）， increased nuclear expression of NF-κB p65 （P0.05）， and significantly elevated expression of p-IKK， p-NF-κB p65， NLRP3， cleaved Caspase-1， ASC， and cleaved IL-1β （P0.05）. Compared with the model group， all drug-treated groups improved learning and spatial memory in VaD rats， alleviated hippocampal pathological injury and neuronal apoptosis， and protected neuronal ultrastructure. Yifei Xuanfei Jiangzhuo prescription at doses of 12.18 and 24.36 g·kg^-1 reduced hippocampal expression levels of p-IKK， p-NF-κB p65， NLRP3， Caspase-1， ASC， and cleaved IL-1β in VaD rats （P0.05）， showing dose-dependent inhibition of the NF-κB/NLRP3 signaling pathway. ConclusionYifei Xuanfei Jiangzhuo prescription may exert neuroprotective effects by regulating the NF-κB/NLRP3 signaling pathway， thereby reducing neuroinflammation and inhibiting hippocampal neuronal apoptosis.

ObjectiveTo investigate the molecular mechanism by which Yifei Xuanfei Jiangzhuo prescription regulates the nuclear factor-κB （NF-κB）/NOD-like receptor protein 3 （NLRP3） signaling pathway to improve neuronal function in vascular dementia （VaD） rats. MethodsA VaD model was established by intermittently clamping the bilateral common carotid arteries （CCA） combined with bilateral vascular occlusion （2-VO）. Eighty-four SD rats were randomly divided into a blank group， sham group， model group， piracetam group （0.2 g·kg^-1）， and low-， medium-， and high-dose Yifei Xuanfei Jiangzhuo prescription groups （6.09， 12.18， and 24.36 g·kg^-1）. Drug administration began on day 7 after surgery， once daily for 28 consecutive days. Behavioral experiments were used to evaluate learning and spatial memory. Hematoxylin-eosin （HE） staining was applied to observe pathological morphological changes in the CA1 region of the hippocampus. Transmission electron microscopy was used to examine the ultrastructure of hippocampal neurons. Terminal deoxynucleotidyl transferase dUTP nick end labeling （TUNEL） was used to detect neuronal apoptosis in the CA1 region. Immunohistochemistry was performed to determine the positive expression rate of neuronal nuclear antigen （NeuN）. Immunofluorescence single staining was used to assess nuclear expression of NF-κB p65 in brain tissue. Western blot was used to detect the protein expression levels of inhibitor of κB kinase （IKK）， NF-κB p65， NLRP3， Caspase-1， apoptosis-associated speck-like protein （ASC）， and interleukin-1β （IL-1β）. ResultsCompared with the blank group， the model group showed a significant reduction in platform-crossing frequency （P0.01）， aggravated hippocampal injury， a significant increase in neuronal apoptosis （P0.05）， decreased NeuN positivity in the CA1 region （P0.05）， increased nuclear expression of NF-κB p65 （P0.05）， and significantly elevated expression of p-IKK， p-NF-κB p65， NLRP3， cleaved Caspase-1， ASC， and cleaved IL-1β （P0.05）. Compared with the model group， all drug-treated groups improved learning and spatial memory in VaD rats， alleviated hippocampal pathological injury and neuronal apoptosis， and protected neuronal ultrastructure. Yifei Xuanfei Jiangzhuo prescription at doses of 12.18 and 24.36 g·kg^-1 reduced hippocampal expression levels of p-IKK， p-NF-κB p65， NLRP3， Caspase-1， ASC， and cleaved IL-1β in VaD rats （P0.05）， showing dose-dependent inhibition of the NF-κB/NLRP3 signaling pathway. ConclusionYifei Xuanfei Jiangzhuo prescription may exert neuroprotective effects by regulating the NF-κB/NLRP3 signaling pathway， thereby reducing neuroinflammation and inhibiting hippocampal neuronal apoptosis.

ObjectiveIn the context of the digital transformation of education, this study aims to construct a triadic interactive teaching model for surgical animal surgery in clinical medicine using modern information technology. It explores the effectiveness of different teaching methods in improving students' practical skills, aseptic awareness, and teamwork abilities, providing a reference for the reform of clinical practice education. MethodsA quasi-experimental research design was adopted. A total of 80 students from the eight-year clinical medicine program at Nanjing University were selected, including the Class of 2020 (control group, n=40) and the Class of 2021 (experimental group, n=40). The control group received traditional teaching methods, while the experimental group implemented the "Teacher-Student-AI" triadic interactive teaching model. This model utilized a smart teaching platform for personalized pre-class preparation , as well as data-driven post-class review and feedback throughout the entire teaching process. The "assessment indicators and scoring criteria for the surgical animal surgery course" were used to evaluate teaching effectiveness, with independent samples t-tests used for statistical analysis. ResultsPre-course assessments revealed no statistically significant differences in baseline theoretical knowledge or practical skills between the two groups (P>0.05). Upon completion of the course, the experimental group achieved higher scores than the control group across three key dimensions: practical skills (47.98±1.34 vs 46.92±2.51, P=0.022), aseptic awareness (17.84±1.16 vs 16.94±2.29, P=0.029), and teamwork (16.82±1.44 vs 15.95±1.22, P=0.004). However, no statistically significant difference was observed in the scores for humane care awareness between the two groups (8.24±0.70 vs 8.16±0.53, P=0.589). ConclusionThe AI-based triadic interactive teaching model can, to some extent, address the limitations of traditional surgical animal surgery education. It plays a positive role in enhancing medical students' surgical skills, aseptic awareness, and collaborative abilities. This model facilitates the transition from traditional to personalized teaching and offers a practical framework for the digital reform of clinical practice education.

BACKGROUND:The mesenchymal stem cell secretome contains bioactive substances,cytokines,and growth factors.Three-dimensional cell culture can regulate the secretion of these components,potentially enhancing the ability to promote injury repair.OBJECTIVE:To investigate the repair effect of three-dimensional cultured human umbilical cord mesenchymal stem cell secretome on skin injuries in mice.METHODS:Human umbilical cord mesenchymal stem cells were cultured in conventional two-dimensional culture dishes and 96-well U-bottom cell culture plates,from which their secretory components were subsequently collected.The expression of skin damage repair related secretory factors in umbilical cord mesenchymal stem cells was analyzed using RT-qPCR.The protein expression level of skin damage repair related factors in umbilical cord mesenchymal stem cell secretome was detected using enzyme-linked immunosorbent assay.The potential of human umbilical cord mesenchymal stem cell secretome to repair vascular injuries was evaluated using an immortalized human umbilical vein endothelial cell migration model.A mouse skin injury model was established,and the human umbilical cord mesenchymal stem cell secretome was injected subcutaneously.Repair effects on skin injury were assessed through wound healing rates and histopathological analysis.RESULTS AND CONCLUSION:(1)After three days of cultivation,human umbilical cord mesenchymal stem cells cultured in two dimensions exhibited a fibroblast-like,swirling growth pattern,whereas three-dimensional culture led to the formation of uniform microspheres.(2)Compared with two-dimensional culture,three-dimensional culture significantly increased the mRNA expression of transforming growth factor β and basic fibroblast growth factor in human umbilical cord mesenchymal stem cells.(3)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly enhanced the protein expression of vascular endothelial growth factor,interleukin-10,and granulocyte-macrophage colony-stimulating factor in the human umbilical cord mesenchymal stem cell secretome.(4)Compared with two-dimensional culture,three-dimensional cultured human umbilical cord mesenchymal stem cell secretome significantly promoted the migration of immortalized human umbilical cord mesenchymal stem cells.(5)Compared with the untreated control group and the two-dimensional cultured human umbilical cord mesenchymal stem cell secretome,the three-dimensional cultured human umbilical cord mesenchymal stem cell secretome can significantly accelerate the skin wound healing rate and wound skin structure remodeling in mice.These results indicate that three-dimensional culture can enhance the expression of paracrine factors of human umbilical cord mesenchymal stem cells,and their secretome can significantly promote the repair of mouse skin damage.

Objective To explore the effect of curcumin(CUR)on oxidative damage of keratinocytes induced by ultraviolet B(UVB)irradiation through Toll-like receptor 4(TLR4)/nuclear factor-kappa B(NF-κB)/nucleotide-binding oligomerization domain-containing protein 3(NLRP3)signaling pathway.Methods Human keratinocytes of HaCaT were cultured normally in vitro,and the keratinocyte oxidative damage model was established by the irradiation of 57 mJ/cm2 UVB.The cells with normal culture were as the control group,the cells treated after modeling were as the UVB group,the cells treated with 5 μmol/L CUR after modeling were as the CUR group,the cells treated with 100 μg/L TLR4 inhibitor of TAK-242 after modeling were as the TAK-242 group,and the cells treated with 5 μmol/L CUR and 100 nmol/L TLR4 activator of lipopolysaccharide(LPS)were as the CUR+LPS group.qRT-PCR was applied to detect the relative expression levels of TLR4,NF-κB,and NLRP3 mRNAs of cells in each group.CCK-8 was applied to detect the cell proliferation in each group.The relative content of reactive oxygen species(ROS),the viabilities of superoxide dismutase(SOD)and catalase(CAT),and the concentrations of glutathione(MDA)and glutathione(GSH)of cells in each group were detected by fluorescence assay according to the kit instruction.ELISA kit was used to detect the expression of inflammatory factors of tumor necrosis factor-α(TNF-α)and interleukin-1β(IL-1β)of cells in each group.Flow cytometry was applied to detect the cell apoptosis in each group.Western blot was applied to detect the expression of proliferation related protein of proliferating cell nuclear antigen(PCNA),apoptosis related proteins[B-cell lymphoma-2(Bcl-2)and Bcl-2-associated X protein(Bax)],and TLR4/NF-κB/NLRP3 signaling pathway related proteins(TLR4,NF-κB and NLRP3)of cells in each group.Results Compared with the Control group,the cell survival rate,the expression levels of PCNA and Bcl-2 proteins,the viabilities of SOD and CAT,and the GSH concentration in the UVB group decreased,while the apoptosis rate,the level of Bax protein,the relative content of ROS,the concentration of MDA,the levels of TNF-α and IL-1β,and the mRNA and protein levels of TLR4,NF-κB and NLRP3 increased(P<0.05).Compared with the UVB group,the cell survival rate,the expression levels of PCNA and Bcl-2 proteins,the viabilities of SOD and CAT,and the GSH concentration in the TAK-242 group and CUR group increased,while the apoptosis rate,the level of Bax protein,the relative content of ROS,the concentration of MDA,the levels of TNF-α and IL-1β,and the mRNA and protein levels of TLR4,NF-κB and NLRP3 decreased(P<0.05).Compared with the CUR group,the cell survival rate,the expression levels of PCNA and Bcl-2 proteins,the viabilities of SOD and CAT,and the GSH concentration in the CUR+LPS group decreased,while the apoptosis rate,the level of Bax protein,the relative content of ROS,the concentration of MDA,the levels of TNF-α and IL-1β,and the mRNA and protein levels of TLR4,NF-κB and NLRP3 increased(P<0.05).Conclusion CUR can increase the antioxidant stress level of keratinocytes,alleviate inflammatory response,promote cell proliferation,and improve cell damage caused by UVB irradiation,which may be related to the inhibition of TLR4/NF-κB/NLRP3 signaling pathway.

Aim To explore the effect of hydroxysafflor yellow A(HSYA)on lipocalin 2(LCN2)-induced fer-roptosis in HT22 cells and the related mechanism.Methods Thirty male Sprague-Dawley(SD)rats were used to establish the middle cerebral artery occlu-sion/reperfusion(MCAO/R)model by the suture method.The rats were randomly divided into the Sham group,the MCAO/R group,and the MCAO/R+HSYA group.The infarct area was measured by TTC staining,and the degree of neurological deficit was evaluated by the Z-Longa scoring method.The expressions of LCN2 and 24P3R in brain tissues were detected by Western blot.LCN2 protein was added to HT-22 cells,and the cells were divided into the normal group,the LCN2 group,and the LCN2+HSYA group.The optimal con-centration of LCN2-induced neuronal ferroptosis was screened by LDH assay and Western blot,and the ex-pression levels of ferritin,FPN1,GPX4,SLC7A11,COX2,and 24P3R were detected.LCN2 was knocked down by siRNA transfection,and the expressions of GPX4 and ferritin were detected.The contents of glu-tathione(GSH),malondialdehyde(MDA),GPX4,and Fe2+were determined by colorimetry,and the expres-sion of GPX4 was detected by immunofluorescence.The binding force between HSYA and LCN2 was ana-lyzed by molecular docking technology.Results Ani-mal experiments showed that HSYA could reduce the cerebral infarction area and decrease the neurological function score of MCAO/R rats.Compared with the sham group,the levels of LCN2 and 24P3R increased in the MCAO/R group,while HSYA inhibited their ex-pressions.Cell experiments showed that the optimal concentration of LCN2 to induce ferroptosis in HT22 cells was 2 μmol·L-1.After knocking down LCN2 by siRNA transfection,compared with the LCN2 group,the expression levels of GPX4 and ferritin in the siLCN2 group increased significantly.Compared with the nor-mal group,the expressions of SLC7A11,GPX4,FPN1,ferritin,and GSH in the LCN2 group decreased signifi-cantly,while the concentration of Fe2+,and the expres-sions of MDA,COX2,and 24P3R increased.HSYA could increase the expressions of SLC7A11,GPX4,FPN1,ferritin,and GSH,reduce the contents of Fe2+and MDA,and inhibit the expressions of COX2 and 24P3R.Molecular docking showed that the binding en-ergy between HSYA and LCN2 was-8.0 kJ·mol-1.Conclusion HSYA can inhibit LCN2-induced ferrop-tosis in HT22 cells through the SLC7A11/GPX4 signa-ling pathway.

Objective:To explore the potential profiles of health literacy in patients with chronic atrophic gastritis (CAG) and analyze their influencing factors.Methods:A cross-sectional study was conducted to select CAG patients admitted to Nanjing Hospital of Traditional Chinese Medicine or attending outpatient clinics from January 2023 to June 2024 by convenience sampling method, and all patients participated in this study two months after treatment. The General Information Questionnaire, the General Self-Efficacy Scale, and the All-around Health Literacy Measurement Scale (AAHLS) were used to conduct the questionnaire survey. The three dimensions of AAHLS were used as exogenous indicators for potential profile analysis, to compare the differences in general information and self-efficacy of patients with different potential profiles, and to analyze the influencing factors of different potential profiles of health literacy in CAG patients by multi classification Logistic regression.Results:The recovery rate of valid questionnaires was 97.71%(256/262). Among the 256 patients, there were 164 males and 92 females, with 86 patients aged 18-44 years old, 110 patients aged 45-59 years old, and 60 patients aged ≥ 60 years old. The health literacy of CAG patients was categorized into 3 potential profiles, including the high health literacy-appraisal and application competence group (14.84%, 38/256), the medium health literacy-appraisal and application competence group (32.81%, 84/256), and the low health literacy-appraisal and application competence group (52.34%, 134/256). The results of multi classification Logistic regression analysis showed that when the low health literacy-appraisal and application competence group was used as a reference, aged 18-44 years old ( OR=8.954, 95% CI 2.049-39.127), poor self-efficacy ( OR=0.089, 95% CI 0.027-0.293), duration of disease <5 years ( OR=0.049, 95% CI 0.014-0.169), per capita monthly household income<3 000 yuan ( OR=0.072, 95% CI 0.018-0.299), and primary school education or below ( OR=0.016, 95% CI 0.003-0.088) were independent influences in the the high health literacy-appraisal and application competence group (all P<0.05); poorer self-efficacy ( OR=0.458, 95% CI 0.251-0.834) and per capita monthly household income<3 000 yuan ( OR=0.212, 95% CI 0.100-0.453) were independent influences in the medium health literacy-appraisal and application competence group (both P<0.05). Conclusions:The health literacy of CAG patients is obviously heterogeneous, and healthcare professionals in clinical work should adopt targeted assessment and intervention according to the different characteristics of each category in order to improve the health literacy of CAG patients.

Objective To analyze the risk factors for meconium-stained amniotic fluid(MSAF)in preterm infants and the clinical outcome and prognosis of preterm infants.Methods Preterm infants with gestational age＜37 weeks delivered in Zhangjiajie People's Hospital from January 2022 to December 2023 were used as the study subjects,31 cases with MSAF were in MSAF group,and 31 cases of preterm infants hospitalized during the same period without MSAF were randomly paired in the ratio of 1∶1 to select with gestational age-body mass matching as non-MSAF group.Retrospective collection and analysis of pregnancy and perinatal conditions of mothers of preterm infants in two groups,comparing the differences of related factors between two groups of children;Logistic regression analysis of risk factors related to MSAF in preterm infants;comparing the complications and clinical outcomes of preterm infants in two groups.Results A total of 387 preterm infants with gestational age＜37 weeks were collected during the study period,including 31 preterm infants with comorbid MSAF,and the prevalence of MSAF in preterm infants was 8.0％.MSAF group had a higher incidence of advanced maternal age,premature rupture of membranes＞18 hours,antepartum fever,and cholestasis during pregnancy than non-MSAF group.Logistic regression analysis suggested that combined cholestasis during pregnancy and white blood cell count ≥ 30× 109/L within 6 hours after birth increased the incidence of MSAF in preterm infants.There was no statistically significant difference in the results of postnatal umbilical artery blood gas analysis between two groups of preterm infants.The proportion of leukocyte count ≥30×109/L,ultrasensitive C-reactive protein＞0.8 mg/L,and interleukin 6＞6 pg/L in MSAF group was higher than that of non-MSAF group in the 6 hours after birth.MSAF group had a higher incidence of intrauterine infectious pneumonia,feeding intolerance,and necrotizing small bowel colitis in neonates than non-MSAF group.Conclusion Advanced maternal age,intrauterine infections,and combined intrahepatic cholestasis during pregnancy may be the major risk factors for MSAF in preterm infants.MSAF preterm infants have a higher prevalence of intrauterine infectious pneumonitis,feeding intolerance,and necrotizing small bowel colitis in newborns,as well as longer hospital stays.