BACKGROUND:Studies have shown that mitochondrial oxidative stress has an important role in the development of knee osteoarthritis,and Hemin can regulate the expression of mitochondria-related proteins. OBJECTIVE:To study the regulatory effect of Hemin on oxidative stress in mouse chondrocytes and its interventional effect and mechanism in knee osteoarthritis. METHODS:(1)In vitro cell experiment:Primary chondrocytes from C57BL/6 mice were extracted and induced with 10 ng/mL interleukin-1β to construct an in vitro chondrocyte model of osteoarthritis.The optimal concentration of Hemin(0,1,10,20,40,80,and 160 μmol/L)for the intervention in mouse chondrocytes was determined by cell counting kit-8 method.Chondrocytes were randomly divided into control group,model group(interleukin-1β)and Hemin group(interleukin-1β+Hemin).Reactive oxygen species,mitochondrial membrane potential and apoptosis of chondrocytes in each group were detected.(2)In vivo experiment:Adult C57BL/6 mice were randomly divided into normal group,model group(osteoarthritis)and Hemin group(osteoarthritis+Hemin),with eight mice in each group.After 4 weeks of Hemin treatment,the behavioral test and histopathological observation of the knee joint were performed in each group.Changes in extracellular matrix-related protein expression and apoptosis in chondrocytes and the expression level of Nrf2/HO-1 protein in cartilage tissue were detected. RESULTS AND CONCLUSION:In vitro experiment:the optimal concentration of Hemin on primary chondrocytes was 40 μmol/L.Compared with the model group,the level of reactive oxygen species was significantly reduced,the mitochondrial membrane potential was significantly improved,and the apoptosis of chondrocytes was reduced in the hemin-treated interleukin-1β-induced chondrocytes.In vivo experiment:After 4 weeks of treatment,compared with the model group,the lower limb function of mice in the Hemin group was significantly improved,the histopathological score was significantly improved,and the apoptosis of knee chondrocytes was significantly reduced.All these findings indicate that Hemin can alleviate oxidative stress,restore mitochondrial function and reduce apoptosis in mouse chondrocytes induced by interleukin-1β.Hemin can improve extracellular matrix degradation,promote chondrocyte anabolism,reduce catabolism and reduce chondrocyte apoptosis in knee osteoarthritis.It may act by activating the chondrocyte Nrf2/HO-1 signaling pathway in the inflammatory environment.

BACKGROUND:Flap transplantation technique is a commonly used surgical procedure for the treatment of severe tissue defects,but postoperative flap necrosis is easily triggered by ischemia-reperfusion injury.Therefore,it is still an important research topic to improve the survival rate of transplanted flaps. OBJECTIVE:To review the pathogenesis and latest treatment progress of flap ischemia-reperfusion injury. METHODS:CNKI,WanFang Database and PubMed database were searched for relevant literature published from 2014 to 2024.The search terms used were"flap,ischemia-reperfusion injury,inflammatory response,oxidative stress,Ca2+overload,apoptosis,mesenchymal stem cells,platelet-rich plasma,signaling pathways,shock wave,pretreatment"in Chinese and English.After elimination of irrelevant literature,poor quality and obsolete literature,77 documents were finally included for review. RESULTS AND CONCLUSION:Flap ischemia/reperfusion injury may be related to pathological factors such as inflammatory response,oxidative stress response,Ca2+overload,and apoptosis,which can cause apoptosis of vascular endothelial cells,vascular damage and microcirculation disorders in the flap,and eventually lead to flap necrosis.Studies have found that mesenchymal stem cell transplantation,platelet-rich plasma,signaling pathway modulators,shock waves,and pretreatment can alleviate flap ischemia/reperfusion injuries from different aspects and to varying degrees,and reduce the necrosis rate and necrosis area of the grafted flap.Although there are many therapeutic methods for skin flap ischemia/reperfusion injury,a unified and effective therapeutic method has not yet been developed in the clinic,and the advantages and disadvantages of various therapeutic methods have not yet been compared.Most of the studies remain in the stage of animal experiments,rarely involving clinical observations.Therefore,a lot of research is required in the future to gradually move from animal experiments to the clinic in order to better serve the clinic.

BACKGROUND:Mesenchymal stem cells can regulate the tumor microenvironment by secreting extracellular vesicles containing cytokines,growth factors and exosomes for the precise regulation of biological behavior of tumor cells. OBJECTIVE:To investigate the effects of human umbilical cord-derived mesenchymal stem cell conditioned medium and their released exosomes on the biological properties of hepatocellular carcinoma cells. METHODS:Human umbilical cord mesenchymal stem cell supernatant was collected,centrifuged and filtered at high speed to obtain human umbilical cord mesenchymal stem cell conditioned medium.Human umbilical cord mesenchymal stem cell supernatant was collected and human umbilical cord mesenchymal stem cell exosomes were extracted by ultra-high speed gradient centrifugation.Human umbilical cord mesenchymal stem cell exosomes were labeled with PKH26 and co-cultured with hepatocellular carcinoma cell MHCC97-H.The uptake of exosomes by MHCC97-H cells was observed by fluorescence microscopy.The effects of human umbilical cord mesenchymal stem cell conditioned medium and human umbilical cord mesenchymal stem cell exosomes on biological functions of hepatocellular carcinoma cells were assessed by the CCK-8 proliferation assay,Transwell migration and invasion assay,and the apoptosis assay. RESULTS AND CONCLUSION:(1)Human umbilical cord mesenchymal stem cell exosomes could be uptaken by MHCC97-H cells and was mainly distributed in the cytoplasm.(2)After treatment with human umbilical cord mesenchymal stem cell conditioned medium,MHCC97-H cells showed a significant increase in proliferation,migration,and invasion(P<0.001,P<0.05,P<0.01),and a significant decrease in apoptosis(P<0.001),while after treatment with human umbilical cord mesenchymal stem cell exosomes,MHCC97-H cells showed a decrease in proliferation(P<0.001)and migration,invasion,and apoptosis were significantly enhanced(P<0.001).(3)The results indicated that human umbilical cord mesenchymal stem cell conditioned medium had the ability to promote the proliferation,migration,invasion,and inhibit apoptosis of MHCC97-H cells,while human umbilical cord mesenchymal stem cell exosomes had the properties of promoting the migration,invasion and apoptosis of MHCC97-H cells,inhibiting the proliferation.

BACKGROUND:In the initial stage of growth plate injury inflammation,platelet-derived growth factor BB promotes the repair of growth plate injury by promoting mesenchymal progenitor cell infiltration,chondrogenesis,osteogenic response,and regulating bone remodeling. OBJECTIVE:To elucidate the action mechanism of platelet-derived growth factor BB after growth plate injury. METHODS:PubMed,VIP,WanFang,and CNKI databases were used as the literature sources.The search terms were"growth plate injury,bone bridge,platelet-derived growth factor BB,repair"in English and Chinese.Finally,66 articles were screened for this review. RESULTS AND CONCLUSION:Growth plate injury experienced early inflammation,vascular reconstruction,fibroossification,structural remodeling and other pathological processes,accompanied by the crosstalk of chondrocytes,vascular endothelial cells,stem cells,osteoblasts,osteoclasts and other cells.Platelet-derived growth factor BB,as an important factor in the early inflammatory response of injury,regulates the injury repair process by mediating a variety of cellular inflammatory responses.Targeting the inflammatory stimulation mediated by platelet-derived growth factor BB may delay the bone bridge formation process by improving the functional activities of osteoclasts,osteoblasts,and chondrocytes,so as to achieve the injury repair of growth plate.Platelet-derived growth factor BB plays an important role in angiogenesis and bone repair tissue formation at the injured site of growth plate and intrachondral bone lengthening function of uninjured growth plate.Inhibition of the coupling effect between angiogenesis initiated by platelet-derived growth factor BB and intrachondral bone formation may achieve the repair of growth plate injury.

BACKGROUND:Liver organoids are of great significance to elucidate the exact pathological mechanism of liver diseases and the treatment of liver diseases. OBJECTIVE:To summarize the basic research in this field at home and abroad,review the important research progress in the construction of liver organoids,disease modeling and transplantation therapy,and discuss the application prospect of combined tissue engineering technology of liver organoids. METHODS:The relevant articles included in PubMed and CNKI databases were searched.The English and Chinese search terms were"liver,organoids,liver diseases."The main search time was from April 2018 to April 2024.Duplicate literature was excluded by manual reading.Finally,94 articles were included for review and analysis. RESULTS AND CONCLUSION:The seed cells constructed by liver organoids are mainly concentrated in adult cells and pluripotent stem cells,which promote the generation of organoids by assisting various cytokines to participate in signal guidance and providing 3D microenvironment by extracellular matrix.However,the overall maturity is not high,which is expected to improve this problem by combining tissue engineering technology.In vitro disease modeling is mainly studied in the field of simple diseases and single-gene genetic diseases.Organoids highly retain patient genetic characteristics,and it is expected to simulate more complex liver diseases and clarify deeper pathological mechanisms by combining CRISPR-Cas9 gene correction and other emerging technologies.In vivo transplantation treatment,liver organoids can be safely and effectively implanted,showing amazing liver function replacement potential,tissue regeneration ability,and may also be combined with other tissue engineering materials to achieve therapeutic purposes.

Objective: To analyze the temporal variation patterns of sickness absenteeism among primary and secondary school students in Shanghai, so as to explore models suitable for predicting peaks and intensity of absenteeism rates. Methods: The seasonal and trend decomposition using loess (STL) method was used to analyze the seasonal and long term trend changes in sickness absenteeism among primary and secondary school students from September 1 in 2010 to June 30 in 2018, in Shanghai. A hierarchical clustering method based on Dynamic Time Warping (DTW) was employed to classify absenteeism symptoms with similar temporal patterns. Based on historical data, the study constructed and evaluated different time series algorithms and machine learning models to optimize the accuracy of predicting the trend of sickness absenteeism. Results: During the research period, the average new absenteeism rate due to illness was 16.86 per 10 000 person day for every academic year, and the trend of sickness absenteeism exhibited both seasonality and a long term upward trend, reaching its highest point in the 2017 academic year (22.47 per 10 000 person day). The symptoms of absenteeism were divided into three categories: high incidence in winter and spring (respiratory symptoms, fever and general discomfort, etc.), high incidence in summer (eye symptoms, nosebleeds, etc.) and those without obvious seasonality (skin symptoms, accidental injuries, etc.).The constructed time series models effectively predicted the trend of absenteeism due to illness, although the accuracy of predicting peak intensity was relatively low. Among them, the multi layer perceptron (MLP) model performed the best, with an root mean squared error (RMSE) of 8.96 and an mean absolute error (MAE) of 4.37, reducing 36.51% and 39.02% compared to the baseline model. Conclusion Time series models and machine learning algorithms could effectively predict the trend of sickness absenteeism, and corresponding prevention and control measures can be taken for absenteeism caused by different symptoms during peak periods.

Promoting the construction of a “Healthy China” is essential to building a great modern socialist country. Health workers in every era have their historical missions and they are the “benevolent doctors” of their own era. Therefore， clarifying the basic connotation and times requirements of “benevolent doctors” has become the first question to be answered in cultivating “benevolent doctors”. The basic connotation of “benevolent doctor” should reflect not only the comprehensive development of moral， intellectual， physical， aesthetic， and labor education in fostering virtue and nurturing talents， but also embody the people-centered development philosophy， promote social equity and justice， and reflect the strategic needs of building a “Healthy China.” Specifically in the practice of medical education， emphasizing both medical science spirit and medical humanities spirit has become an important path to cultivate “benevolent doctors” in the new era.

ObjectiveTo analyze the development trajectory， research hotspots， and trends in medical humanities research in China since the new era. MethodsA search was conducted on the CNKI （China National Knowledge Infrastructure） advanced search page using the themes“medical humanities”or “humanistic medicine，”retrieving a total of 5，758 articles. After applying specific screening criteria， 5，095 articles were included in the analysis. Citespace6.1.R6 was used to visualize and analyze the authors， institutions， and keywords of the 5，095 articles. ResultsSince the new era， the volume of publications on medical humanities in China has shown an overall upward trend， with limited collaboration between core institutions and core authors. The research content of medical humanities has evolved from broad to specific， from abstract to concrete， and from theoretical to practical. ConclusionThe development of medical humanities research in China has generally gone through three stages： defining related concepts， integrating medical humanistic spirit into clinical practice， and applying empirical methods. Narrative medicine， ideological and political education in curricula， and medical humanities education are potential future research directions.

ObjectiveTo observe the clinical efficacy and safety of Bushen Ruyan Formulation （补肾乳岩方， BRF） in treating premenopausal breast cancer patients of disharmony of the chong （冲） and ren （任） meridian type under endocrine intensive therapy. MethodsA total of 88 premenopausal breast cancer patients who received endocrine intensive therapy and were diagnosed with disharmony of the chong and ren meridian by traditional Chinese medicine （TCM） were included and randomly divided into a control group and a treatment group， with 44 cases in each group. The control group received ovarian function suppression （OFS） combined with endocrine therapy， while the treatment group was given oral BRF additionally. Both groups were treated for three months. The clinical efficacy was evaluated by comparing the pre- and post-treatment results of the Functional Assessment of Cancer Therapy-Breast （FACT-B）， modified Kupperman score， T cell subsets （CD3⁺， CD4⁺， CD8⁺， CD4⁺/CD8⁺）， sex hormone levels， including estradiol （E₂）， luteinizing hormone （LH）， follicle-stimulating hormone （FSH）， progesterone （P）， testosterone （T）， and prolactin （PRL）， tumor markers， such as carcinoembryonic antigen （CEA）， carbohydrate antigen 125 （CA125）， and carbohydrate antigen 153 （CA153）， TCM syndrome score， and TCM syndrome efficacy. Blood routine tests， liver function and kidney function were monitored to assess safety. ResultsThe FACT-B scores of each domains and the total scores of the treatment group increased， while the social/family status score of the control group decreased. The treatment group had significantly higher scores in all domains and total score compared to the control group （P＜0.05 or P＜0.01）. The modified Kupperman score and TCM syndrome score of the treatment group decreased， and were lower than those of the control group （P＜0.01）. The levels of CD3⁺ and CD4⁺ in the treatment group increased， and were higher than those of the control group （P＜0.05）. Serum testosterone levels in the treatment group were lower than those in the control group （P＜0.05）. The total effective rate of TCM syndrome efficacy in the treatment group was 67.44%， significantly higher than the 23.26% in the control group （P＜0.05）. No significant abnormalities were observed in the blood routine tests or liver/kidney function indicators in either group before or after treatment. ConclusionBRF can effectively improve quality of life， alleviate symptoms， increase serum CD3⁺ and CD4⁺ levels， and enhance clinical efficacy in premenopausal breast cancer patients undergoing endocrine intensive endocrine therapy. It is also safe with no significant adverse effects.

To investigate the awareness of cognitive impairment disorders among residents of the Xizang Autonomous Region and its influencing factors, thereby providing a basis for targeted prevention and treatment efforts.