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.

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.

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.

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 and analyze the source of infection in an outbreak of gastroenteritis in a kindergarten of Xinjiang Production and Construction Corps, and to provide a reference for formulating targeted epidemic prevention and control strategies. MethodsCases were identified through face-to-face interviews, telephone follow-ups, and by reviewing kindergarten attendance records, medical institution outpatient logs, and admission/discharge registers. Fecal samples, vomitus, anal swabs, food samples, leftover ingredients, and environmental samples from cafeteria and classrooms were collected. These samples were simultaneously screened for norovirus using real-time fluorescent reverse transcription polymerase chain reaction (RT-PCR) and for enteric pathogens such as Salmonella, diarrheagenic Escherichia coli, and Staphylococcus aureus using real-time fluorescent quantitative PCR. ResultsFrom May 7 to 10, 2024, a total of114 children (64 boys and 50 girls) were enrolled in the kindergarten, including 26 children in the younger class. A total of 15 norovirus cases were identified, all from the younger class, resulting in an overall attack rate of 13.16% (15/114). The main clinical symptoms included vomiting (93.33%), diarrhea (80.00%), fever (20.00%), and abdominal pain (6.67%). The male-to-female case ratio was 1.5∶1, with most cases occurring among the 4-year-old age group, accounting for 73.33% (11/15) of all cases. The outbreak lasted 63.67 h. A total of 42 samples were collected, including 13 clinical specimens (5 vomit samples, 7 fecal samples, and 1 anal swab), 4 food samples and leftover ingredients from the 48-hour food retention period, 5 environmental samples from the cafeteria, and 20 environmental samples from the younger class classroom (3 storage boxes, 2 bedding sets, 4 LEGO walls, 3 watercolor pens, 4 toy cabinets, 3 cup-swab samples, and 1 tap water sample from the direct drinking water dispenser). RT-PCR results showed a positivity rate of 53.85% (7/13) among patient specimens, with 5 cases testing positive for norovirus GⅡ genotype. The positivity rates for vomitus and fecal samples were 40.00% (2/5) and 71.43% (5/7), respectively. Norovirus GⅡ genotype was detected in 5 of 20 environmental samples from the younger class classroom, yielding a positivity rate of 25.00%(5/20). However, all food, drinking water, and cafeteria environmental samples were negative. ConclusionThis incident is an outbreak and cluster of infections caused by norovirus GⅡ in a kindergarten and the critical factor is that the index case entered the kindergarten while ill. It is necessary to strengthen health education, enhance the disease prevention awareness of teachers, students and parents, develop good hygiene habits, and achieve early detection, reporting, and timely control of such incidents.

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.

Objective:To compare the accuracy and applicability of three adult height prediction methods based on artificial intelligence-assisted bone age assessment—the Bayley-Pinneau method(BP method), the Tanner-Whitehouse 3 method(TW3 method), and China 05 method—in girls.Methods:This bidirectional cohort study collected clinical data and 690 posteroanterior X-ray images of the left hand from 278 female children who underwent pubertal development assessments at Shenzhen Children′s Hospital between January 2014 and December 2020, with follow-up until adult height was reached. Adult height prediction was performed using BP, TW3, and China 05 methods on artificial intelligence-assisted bone age assessment.Results:The BP and TW3 methods overestimated adult height by(1.7±3.7) cm and(2.6±3.0) cm, respectively, while the China 05 method underestimated adult height by(2.3±3.5) cm. The proportion of PAH within±5 cm of FAH were 80.0% for the TW3 method, 77.0% for the BP method, and 74.2% for the China 05 method, with significant differences among them( P=0.038). Analysis of cases with prediction deviations>10 cm and subgroup comparisons revealed that the TW3 and BP methods were more likely to overestimate adult height in girls aged 6.0-<8.0 years, with delayed bone age, or in the prepubertal stage(all P<0.001). The China 05 method was more prone to underestimate adult height in those with advanced bone age( P<0.001). All three methods showed significantly greater prediction errors(absolute difference between PAH and FAH) in girls with early puberty compared to those with normal pubertal development(all P<0.05). Conclusions:The TW3 and BP methods tend to overestimate adult height in girls, while the China 05 method tends to underestimate it. Caution is warranted when predicting adult height, particularly in girls under 8 years of bone age, with delayed or advanced bone age, and those with early puberty.

Objective:To investigate the effects and mechanisms of cyclic adenosine monophosphate (cAMP) on cisplatin-induced acute kidney injury (AKI).Methods:GSE227970 dataset derived from human renal tubular epithelial cells (HK-2 cells) in the GEO database was downloaded, and Kyoto Encyclopedia of Genes and Genomes and Gene Ontology analysis were performed in normal and cisplatin-damaged cells. Eighteen 8-week-old male C57BL/6J mice with body weight of (22±2) g were randomly divided into normal group, cisplatin group and cAMP group according to random number table method, with 6 mice in each group. cAMP group was intraperitoneally injected with 30 mg/kg glumine cyclic adenosine monophosphate, while normal group and cisplatin group were intraperitoneally injected with the same volume of 0.9% sodium chloride solution for 10 consecutive days. The cisplatin and cAMP groups were intraperitoneally injected with 20 mg/kg cisplatin once on the 8th day. The body weight and kidney weight of mice were weighed, and kidney weight to body weight ratio was calculated. The blood urea nitrogen (BUN) and serum creatinine (Scr) in mice were detected. HE staining was used to evaluate the degree of renal injury. Western blotting was used to detect the protein expression of AMP-activated protein kinase (AMPK)/acetyl-CoA carboxylase (ACC) signaling pathway in renal tissues. In vitro experiments, HK-2 cells were set up in normal group, cisplatin group, cAMP group and cAMP+AMPK inhibitor group. Immunofluorescence was used to detect the protein expression of phosphorylated (p)-AMPK in HK-2 cells. Adenosine triphosphate content and ratio of NAD + to NADH in cells were detected. Flow cytometry was used to detect cell apoptosis. Results:Biological signal analysis showed that axon guidance, Ras-related protein 1 signaling pathway and cAMP signaling pathway were significantly changed in cisplatin group. The body weight, kidney weight and kidney weight/body weight ratio in cisplatin group were significantly lower than those in normal group (all P<0.05). However, after cAMP treatment, kidney weight was significantly higher compared with cisplatin group ( P<0.05), and body weight and kidney weight/body weight ratio also increased, but the differences were not statistically significant (both P>0.05). BUN, Scr and renal tubular injury score in cisplatin group were significantly higher than those in normal group (all P<0.05). After cAMP treatment, BUN, Scr and renal tubular injury score were significantly lower than those in cisplatin group (all P<0.05). Western blotting results showed that cAMP treatment could significantly increase the decreased AMPK/ACC signaling pathway protein in the renal tissues of cisplatin-induced mice (all P<0.05). In vitro experiments, immunofluorescence detection showed that the expression of p-AMPK protein in cisplatin-induced HK-2 cells decreased, and the addition of cAMP increased the expression of p-AMPK protein in cisplatin-induced HK-2 cells (all P<0.05). cAMP treatment could alleviate cisplatin-induced injury in HK-2 cells, restore the reduction of adenosine triphosphate content and NAD +/NADH ratio, and reduce the apoptosis induced by cisplatin (all P<0.05), while AMPK inhibitor could eliminate the protective effect of cAMP on cisplatin-induced injury in HK-2 cells. Conclusion:cAMP can play a protective role in renal injury caused by cisplatin, and its mechanism may be related to activation of AMPK/ACC signaling pathway.

Objective:To investigate the clinical diagnosis,treatment and prognosis of traumatic ectopic testis with torsion.Methods:We retrospectively analyzed the clinical data on a case of traumatic ectopic testis with torsion and reviewed relevant litera-ture.Results:After diagnosed with traumatic ectopic testis with torsion,the patient underwent exploratory operation for confirmation of orchiocatabasis,followed by testicular reduction and fixation.Follow-up visit at 1 month after surgery showed good blood supply and no obvious testicular atrophy.Conclusion:Traumatic ectopic testis with torsion is an extremely rare emergency condition,for which color Doppler ultrasonography is an effective means of examination.Once suspected of or confirmed with the problem,the patient should receive exploratory surgery,testicular reduction and fixation within 6 hours,and close postoperative observation.