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.

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.

[摘 要] 目的：探讨lncRNA DLEU2通过EZH2/H3K27me3途径调控IKKα介导甲状腺癌（TC）放射性碘抵抗的作用机制。方法：利用TCGA数据库分析TC中DLEU2的表达及其与EZH2的相关性。构建放射性碘抵抗的TPC-1细胞（RR-TPC-1细胞）模型及裸鼠移植瘤模型，通过敲低或过表达DLEU2（si-DLEU2/OE-DLEU2）、抑制EZH2（UNC1999）、过表达IKKα（OE-IKKα）进行干预，采用qPCR、WB、RIP、ChIP、CCK-8、流式细胞术、TUNEL染色及体内成瘤实验检测基因与蛋白表达、表观修饰、细胞增殖、凋亡及肿瘤生长。结果：TCGA分析显示，DLEU2在TC组织中显著上调（P < 0.001），与患者不良预后相关（P = 0.008 4），且与EZH2表达呈正相关（r = 0.390, P < 0.001）；RIP证实EZH2与DLEU2存在相互作用/结合（P < 0.05）。体外实验表明，敲低DLEU2可显著下调RR-TPC-1细胞中EZH2、IKKα表达及H3K27me3修饰水平，抑制NF-κB通路活化（P < 0.05或P < 0.01），抑制细胞增殖、促进凋亡（均P < 0.05）。联合敲低DLEU2与抑制EZH2进一步增强上述效应，而过表达IKKα则可部分逆转上述效应（P < 0.05或P < 0.01）。体内实验进一步证实，敲低DLEU2联合抑制EZH2可显著抑制移植瘤生长，增加肿瘤细胞凋亡（均P < 0.01）；IKKα过表达则部分逆转上述抗肿瘤效应（P < 0.05或P < 0.01）。结论：lncRNA DLEU2通过招募EZH2催化H3K27me3修饰，间接激活IKKα/NF-κB信号并形成正反馈环路，介导TPC-1细胞131I抵抗。

Objective To understand the antibody levels of diphtheria and tetanus among healthy population in Shanghai Pudong New Area, and to provide a scientific basis for improving the vaccine immunization strategy. Methods Random sampling was used to select healthy people of all ages in 16 communities in Shanghai Pudong New Area from 2018 to 2024, and serum samples were collected and tested for serum anti-diphtheria and tetanus toxin IgG antibodies by enzyme-linked immunosorbent assay (ELISA) method to analyze the antibody positivity rate (≥0.1 IU/ml) and the geometric mean concentration (GMC) of antibodies. Results A total of 3 312 serum samples were included, with a male-to-female ratio of 0.76:1, and 53.77% were local residents. The seropositivity rates and geometric mean concentrations (GMC) of both diphtheria and tetanus antibodies generally declined with increasing age, but exhibited a transient rebound in the 7y-. A total of 1 175 individuals (35.48%) were seropositive for diphtheria, with a GMC of 0.054 IU/mL. For tetanus, 988 individuals (29.83%) were seropositive, with a GMC of 0.033 IU/mL. Significant differences in seropositivity rates (χ²_diphtheria=950.005,χ²_tetanus=1 324.393) and GMC (H_diphtheria=1027.160,H_tetanus=1 142.007) were observed among different age groups (P<0.001). Significant differences in seropositivity rates (χ²_diphtheria=950.005,χ²_tetanus=1324.393) and GMC (H_diphtheria=1027.160,H_tetanus=1142.007) were also found across different years (P<0.001). Conclusion The prevalence of diphtheria and tetanus antibodies in the healthy population of Pudong New Area is relatively low, particularly among adults over 20 years of age with inadequate immunization. This underscores the need to reinforce the National Immunization Program (NIP) vaccine specifications for children under 6 years of age and implement an immunization strategy for adolescents or adults against diphtheria and tetanus.

Objective: To explore the effects of a classroom based transdiagnostic preventive intervention program for emotional disorders on depressive and anxiety symptoms, and resilience among junior high school students, so as to provide reference for promoting adolescent mental health. Methods: From October to December 2023, 72 students from a junior high school in Beijing were recruited as research subjects and divided into an intervention group ( n =36) and a control group ( n =36). The intervention group participated in 8 sessions (40 mins per session) of transdiagnostic prevention intervention course for emotional disorders; the control group students participated in research based learning lessons or class meetings. Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7), and Resilience Scale-8 (RS-8) were used to evaluate junior high school students. The Wilcoxon signed rank test was used to compare the differences in depressive and anxiety symptoms, and resilience scores between the intervention group and the control group before and after the intervention. PROCESS macro was used to test the mediating effect. Results: There were no statistically significant differences in the scores of depressive and anxiety symptoms, and resilience before and after intervention in the intervention group ( Z =-1.07, 0.07, 1.43, all P >0.05). In the control group, the depressive symptoms score was higher after the intervention than before, and the resilience score was lower than before the intervention ( Z = 2.23 , -2.53, both P <0.05). After intervention, the depressive symptoms score in the intervention group was lower than that in the control group, and the resilience score in the intervention group was higher than that in the control group ( Z =-2.09, 3.33, both P < 0.05). The increase in the scores of resilience played a complete mediating role between the intervention and depressive symptoms, with the mediating effect value being -0.98 (95% CI =-2.47 to -0.11), accounting for 30.98% of the total effect. Conclusion Transdiagnostic preventive intervention program for emotional disorders based on classroom could prevent the deterioration of depressive symptom in junior high school students, and maintaining the level of resilience is an important factor for the intervention effect.

Objective To explore the method for establishing a pig left lung orthotopic transplantation model. Methods A total of 4 male Yorkshire pigs weighing (40.0±2.5) kg underwent surgical procedures, including anesthesia, tracheal intubation, donor lung procurement, and recipient lung transplantation. Histological morphology and blood gas analysis of the transplanted lungs were assessed 2 hours after reperfusion to evaluate the histological changes and function of the transplanted lungs. Results The pigs underwent left lung in situ transplantation, effectively simulating conditions relevant to human lung transplantation. Two hours after the transplantation, arterial blood gas analysis showed that arterial partial pressure of oxygen was 155.4-178.6 mm Hg, arterial partial pressure of carbon dioxide was 53.1-62.4 mm Hg, and the oxygenation index was 310.8-357.2 mm Hg. Hematoxylin and eosin staining indicated a low degree of pulmonary edema and minimal cellular infiltration. Conclusion The pig left lung orthotopic transplantation model possesses strong operability and stability. Researchers can replicate this model according to the described methods and further conduct basic research and explore clinical translational applications.

Abstract In April 2021, type Ⅰ vaccine-derived poliovirus (VDPV) was detected from two fecal samples of a male infant with acute flaccid paralysis (AFP) in Zhejiang Province when he was admitted to the Children's Hospital Affiliated to Fudan University in Shanghai, with 12 and 14 nucleotide mutations in the VP1 region, respectively. The case had a history of immunization with three doses of poliovirus vaccines, and grade Ⅲ proximal muscle strength and grade Ⅱ distal muscle strength of the right lower limb. After symptomatic treatment, the activity of the right lower limb and the muscle strength was significantly restored, thus he was discharged. VDPV was not detected from subsequent (the 8th to 12th) fecal samples of the case and fecal samples of close contacts. No similar cases were found in medical institutions in the county, surrounding areas, neighboring villages or towns. Since the case did not exhibit clinical symptoms of poliomyelitis caused by VDPV, poliomyelitis was excluded, and the case was diagnosed with hemophilia type A based on the epidemiological investigation, laboratory tests, and the history of poliomyelitis vaccination. This event involved cross-provincial (municipal) cooperation and was responsed promptly, preventing further spread of the virus. It suggested that the sensitivity of the AFP case surveillance system should be maintained, environmental monitoring methods should be increased, and the poliomyelitis vaccination should be promoted to prevent the spread of the virus.

ObjectiveTo investigate the clinical efficacy and safety of state-target formula Angelica and Safflower spot removal essence in the treatment of melasma. MethodsA randomized，double-blind，placebo-controlled parallel-group trial was conducted，selecting patients with Qi stagnation and blood stasis type of melasma who visited the dermatology outpatient department of Beijing Hospital of Integrated Traditional Chinese and Western Medicine from September 2022 to February 2023. In accordance with the double-blind principle，a random number table was generated to randomly divide the patients into an experimental group （50 cases） and a control group （50 cases）. The experimental group applied the Angelica and Safflower spot removal essence topically，while the control group applied a placebo topically，with continuous treatment for 8 weeks and a follow-up of 1 month. Melasma Area and Severity Index （MASI），Physician Global Assessment （PGA），patient self-assessment scoring，VISIA detection and scoring were performed before medication and on the first day after stopping medication，and all adverse events were recorded. ResultsIn a study involving 100 patients，87 cases were included in the analysis. The experimental group consisted of 45 cases，with 5 dropouts，and the control group had 42 cases，with 8 dropouts. The baseline data of the patients in both groups were consistent，with no statistically significant differences. After treatment，the total effective rate of the experimental group was 75.56% （34/45），significantly higher than the control group's 2.38% （1/42），and the difference was statistically significant （χ²=48.38，P<0.01）. Compared with before treatment，after treatment，the MASI score，VISIA image spot，brown spot，and red area score of the experimental group patients were significantly reduced （P<0.05，P<0.01），while there was no statistically significant difference in the control group patients. Compared with the control group after treatment，the experimental group showed more significant improvement （P<0.05，P<0.01）. VISIA image analysis showed that after 8 weeks of treatment，the experimental group showed significant improvement in surface spots，deep spots，and red areas，while the control group remained unchanged or showed an increasing trend. 42.22% （19/45） of the experimental group had a PGA score of 3 or below，while 88.89% （40/45） had a PGA score of 4 or below. 80.95% （34/42） of the control group had a PGA score of 5 or above，and the difference between the two groups was statistically significant （χ²=38.26，P<0.01）. There was no statistically significant difference in the recurrence rate and adverse reaction rate within one month between the experimental group and the control group. ConclusionThe state-target formula Angelica and Safflower spot removal essence is clinically effective and safe in the treatment of melasma.

ObjectiveTo study on the different therapeutic effects and potential mechanisms of Rhei Radix et Rhizoma（RH） before and after steaming with wine on constipation model mice. MethodsFifty-four male ICR mice were randomly divided into control group， model group， lactulose group（1.5 mg·kg^-1）， high， medium and low dose groups of RH and RH steaming with wine（PRH）（8， 4， 1 g·kg^-1）. Except for the control group， the constipation model was replicated by gavage of loperamide hydrochloride（6 mg·kg^-1） in the other groups. After 2 weeks of modeling， each administration group was gavaged with the corresponding dose of drug solution， and the control and model groups were given an equal volume of normal saline， 1 time/d for 2 consecutive weeks. After administration， the feces were collected for 16S rRNA sequencing， the levels of gastrin（GAS）， motilin（MTL）， interleukin-6（IL-6）， γ-interferon（IFN-γ） in the colonic tissue were detected by enzyme-linked immunosorbent assay（ELISA）， the histopathological changes of colon were observed by hematoxylin-eosin（HE） staining， flow cytometry was used to detect the proportion changes of CD4⁺， CD8⁺ and regulatory T cell（Treg） in peripheral blood. ResultsCompared with the control group， the model group showed significantly decrease in fecal number in 24 h， fecal quality and fecal water rate（P<0.01）， the colon was seen to have necrotic shedding of mucosal epithelium， localized intestinal glands in the lamina propria were degenerated， necrotic and atrophied， a few lymphocytes were seen to infiltrate in the necrotic area in a scattered manner， the contents of GAS and MTL， the proportions of CD4⁺， CD8⁺ and Treg were significantly reduced（P<0.01）， the contents of IL-6 and IFN-γ were significantly elevated（P<0.05， P<0.01）. Compared with the model group， the fecal number in 24 h， fecal quality and fecal water rate of high-dose groups of RH and PRH were significantly increased（P<0.05， P<0.01）， the pathological damage of the colon was alleviated to varying degrees， the contents of GAS， MTL， IL-6 and IFN-γ were significantly regressed（P<0.05， P<0.01）， and the proportions of CD4⁺ and CD8⁺ were significantly increased（P<0.01）， although the proportion of Treg showed an upward trend， there was no significant difference. In addition， the results of intestinal flora showed that the number of amplicon sequence variant（ASV） and Alpha diversity were decreased in the model group compared with the control group， and there was a significant difference in Beta diversity， with a decrease in the relative abundance of Lactobacillus and an increase in the relative abundances of Bacillus and Helicobacter. Compared with the model group， the ASV number and Alpha diversity were increased in the high-dose groups of RH and PRH， and there was a trend of regression of Beta diversity to the control group， the relative abundance of Lactobacillus increased， and the relative abundances of Bacillus and Helicobacter decreased. ConclusionRH and PRH can improve dysbacteriosis， promote immune system activation， inhibit the release of inflammatory factors for enhancing the gastrointestinal function， which may be one of the potential mechanisms of their therapeutic effect on constipation.

ObjectiveA multiplex amplification system was constructed based on the capillary electrophoresis platform for simultaneous detection of saliva, semen, and vaginal secretions using tissue-specific RNA markers. The aim of this study is to identify the tissue origin of suspicious body fluid stains found at crime scenes and determine whether the body fluid stains at the crime scene are one or several types among saliva, semen, and vaginal secretions. MethodsThirty saliva samples, forty semen samples, and forty vaginal secretion samples (half from 2015 and half from 2024) were collected from healthy adult volunteers. Through primer designing, system formulation, and PCR condition optimization, a multiplex fluorescent amplification system was constructed. The specificity, sensitivity, and detection ability for mixed samples of this system were investigated, and it was tested using real crime scene materials. In the primer design stage, to reduce the requirements for RNA template quality, the amplification products were set within 80-300 bp. In the system formulation stage, dominant and subordinate primers were mainly considered. By reducing the concentration of dominant primers and increasing that of subordinate primers, a capillary electrophoresis spectrum with an appropriate peak height ratio was finally obtained. Additionally, gradient experiments were designed to adjust the concentrations of PCR reagents and PCR amplification conditions, and multiple versions of DNA amplification enzymes were optimized to achieve the best experimental results. ResultsThrough statistical analysis, there was no significant difference in the capillary electrophoresis of the 3 types of body fluid samples from the two years (2015 and 2024), demonstrating that the sample preservation method in this study can preserve samples for a relatively long time. The composite amplification system constructed in this study exhibited high specificity for all 3 types of body fluid, with no cross-reactions between the markers of each type of body fluid. The minimum detection thresholds for the 3 types of body fluid reached 0.002 9, 0.001 5, and 0.42 mg/L, respectively. This system also had a high degree of discrimination for mixed samples, especially for semen-saliva mixtures, where each body fluid marker could still be successfully detected when the concentration ratio of semen to saliva was 100:1. Meanwhile, in the two actual cases presented in this article, the application of this composite amplification system performed outstandingly. ConclusionThe composite amplification detection system constructed in this study can achieve the correct screening of saliva, semen, and vaginal secretions, overcoming the problems such as low specificity and sensitivity of marker tests and unbalanced RFU values of each marker in previous studies. The specificity and sensitivity meet the practical work requirements, and the operation is simple. It provides an analytical and identification method for body fluid stains in actual case and is applicable to the identification of the tissue origin of biological evidence at crime scenes involving sexual assault, indecent assault, and other criminal acts. In the future, more types of body fluid markers will be screened to expand the types of body fluids detected by the system, and body fluid-specific cSNP and cInDel genetic markers will be introduced to infer the sources (individuals and types) of mixed and complex stains more accurately.