Postoperative infection of internal fixation of closed fractures the lower limbs in adults represents a devastating complication, characterized by diagnostic challenges, prolonged treatment duration and high disability rates. Current management of these infections faces multiple challenges, such as difficulties in early accurate diagnosis, and various controversies about the treatment plan, leading to poor overall diagnosis and treatment results. To address these issues, based on evidence-based medicine and principles with emphasis on scientific rigor, clinical applicability and innovation, the Trauma Branch of the Chinese Medical Association, Orthopedic Branch of the Chinese Medical Doctor Association, Orthopedics Branch of the Chinese Medical Association, and Trauma Orthopedics and Polytrauma Group of the Resuscitation and Emergency Committee of the Chinese Medical Doctor Association have collaboratively organized a panel of relevant experts to develop the Guideline for diagnosis and treatment of infection after internal fixation of closed lower limb fractures in adults ( version 2025). The guideline proposed 10 recommendations, aiming to provide a foundation for standardized diagnosis and treatment of postoperative infection in adults with closed lower limb fractures.

Recently developed three-dimensional echocardiography rendering technology，which includes transillumination imaging and tissue transparency imaging，is based on powerful artificial intelligence algorithm and employs unique visualization methods. This novel technology enables intuitive and realistic visualization of the heart's three-dimensional structure and blood flow images，providing richer and more accurate imaging information for evaluating cardiac anatomy and function. They demonstrate unique value in the diagnosis and treatment of structural heart diseases. This article reviews the applications and prospects of three-dimensional echocardiographic rendering techniques in structural heart disease.

Objective:To explore the application value of echocardiography in the management of pediatric mitral valve replacement.Methods:Thirty-three children who underwent mitral valve replacement at Union Hospital Tongji Medical College Huazhong University of Science and Technology from January 2009 to June 2023 were retrospectively analyzed. Clinical data and preoperative and postoperative echocardiographic data were collected. The differences in ultrasound parameters among preoperative，1-week postoperative，1-month postoperative and 1-year postoperative were compared.Results:Of the 33 children，there were 4 cases（12.12%）of mitral stenosis，33 cases（100%）of mitral regurgitation and 4 cases（12.12%）of mitral stenosis combined with regurgitation. Mechanical valve replacement was performed in 30 cases（90.91%）and bioprosthetic valve replacement in 3 cases（9.09%）. Compared with the preoperative period，the left atrial internal diameter and left ventricular end-diastolic internal diameter were significantly reduced at 1-week postoperatively，1-month postoperatively，and 1-year postoperatively，respectively（all P <0.05）.The left ventricular mass was significantly reduced and the left ventricular end-diastolic sphericity index was significantly increased（both P < 0.05）at 1-month postoperatively compared with preoperatively. The left ventricular ejection fraction was significantly higher at 1-year postoperatively compared with 1-week postoperatively（ P <0.05）. Conclusions:After pediatric mitral valve replacement，the left ventricular dimensions decrease，and cardiac function progressively recovers. Echocardiography is an essential tool for accurate preoperative assessment and postoperative follow-up in pediatric mitral valve replacement.

BACKGROUND:Micro-robots have the characteristics of small size,flexibility,and strong targeting,and can complete complex tasks in a single or clustered manner in a narrow environment.With the continuous optimization of materials,preparation processes,and driving approaches,they have shown increasingly important application value in the field of biomedicine. OBJECTIVE:To analyze the application of field-driven micro-robots in medical field and to look forward to their application prospect. METHODS:Using"microrobots,nanorobots,drivers,biomedical,medical"as Chinese keywords and"microrobots,micro-robots,nanorobots,micromachine,microswimmer,medical"as English keywords,WanFang Data and PubMed databases were searched,respectively.The search time range was from January 2010 to January 2024,and a small number of long-term articles were included.Through reading the titles and preliminarily screening the abstracts,the repetitive studies,low-quality journals,and irrelevant literature were excluded.After reading the entire text,66 papers were finally included for review. RESULTS AND CONCLUSION:Field-driven medical micro-robots mainly include magnetic,optical,thermal,ultrasonic,and multi-mixed factor-driven robots.Field-driven robots have been used in intestinal diagnosis,drug targeting therapy,and stem cell therapy.Medical micro-robots are currently only used in a small number of clinical applications,but most of which are still in the theoretical and experimental stages.Medical micro-robots will face many challenges in future,such as large-scale preparation,precise control of micro-robots,recycling or degradation in vivo,whether the materials used will cause adverse reactions to the human body,and the related minimally invasive medical procedures.

In recent years，the incidence and prevalence of non-tuberculous mycobacterial（NTM）infections have been on the rise，posing a serious threat to public health and presenting significant challenges for disease management. Currently，the treatment outcomes for NTM disease are poor，one of the main reasons being the high resistance of NTM pathogens to various anti-mycobacterial drugs. Novel therapeutic strategies targeting the host rather than the NTM pathogens themselves may help improve cure rates and reduce mortality. This article summarizes the latest research findings on host factors related to the incidence of NTM disease，including age，pulmonary diseases，immune function，genetic factors and lifestyle，which aids in the early identification of high-risk populations and provides a theoretical basis for developing targeted prevention and treatment strategies and optimizing treatment plans.

Postoperative infection of internal fixation of closed fractures the lower limbs in adults represents a devastating complication, characterized by diagnostic challenges, prolonged treatment duration and high disability rates. Current management of these infections faces multiple challenges, such as difficulties in early accurate diagnosis, and various controversies about the treatment plan, leading to poor overall diagnosis and treatment results. To address these issues, based on evidence-based medicine and principles with emphasis on scientific rigor, clinical applicability and innovation, the Trauma Branch of the Chinese Medical Association, Orthopedic Branch of the Chinese Medical Doctor Association, Orthopedics Branch of the Chinese Medical Association, and Trauma Orthopedics and Polytrauma Group of the Resuscitation and Emergency Committee of the Chinese Medical Doctor Association have collaboratively organized a panel of relevant experts to develop the Guideline for diagnosis and treatment of infection after internal fixation of closed lower limb fractures in adults ( version 2025). The guideline proposed 10 recommendations, aiming to provide a foundation for standardized diagnosis and treatment of postoperative infection in adults with closed lower limb fractures.

Recently developed three-dimensional echocardiography rendering technology，which includes transillumination imaging and tissue transparency imaging，is based on powerful artificial intelligence algorithm and employs unique visualization methods. This novel technology enables intuitive and realistic visualization of the heart's three-dimensional structure and blood flow images，providing richer and more accurate imaging information for evaluating cardiac anatomy and function. They demonstrate unique value in the diagnosis and treatment of structural heart diseases. This article reviews the applications and prospects of three-dimensional echocardiographic rendering techniques in structural heart disease.

Objective:To explore the application value of echocardiography in the management of pediatric mitral valve replacement.Methods:Thirty-three children who underwent mitral valve replacement at Union Hospital Tongji Medical College Huazhong University of Science and Technology from January 2009 to June 2023 were retrospectively analyzed. Clinical data and preoperative and postoperative echocardiographic data were collected. The differences in ultrasound parameters among preoperative，1-week postoperative，1-month postoperative and 1-year postoperative were compared.Results:Of the 33 children，there were 4 cases（12.12%）of mitral stenosis，33 cases（100%）of mitral regurgitation and 4 cases（12.12%）of mitral stenosis combined with regurgitation. Mechanical valve replacement was performed in 30 cases（90.91%）and bioprosthetic valve replacement in 3 cases（9.09%）. Compared with the preoperative period，the left atrial internal diameter and left ventricular end-diastolic internal diameter were significantly reduced at 1-week postoperatively，1-month postoperatively，and 1-year postoperatively，respectively（all P <0.05）.The left ventricular mass was significantly reduced and the left ventricular end-diastolic sphericity index was significantly increased（both P < 0.05）at 1-month postoperatively compared with preoperatively. The left ventricular ejection fraction was significantly higher at 1-year postoperatively compared with 1-week postoperatively（ P <0.05）. Conclusions:After pediatric mitral valve replacement，the left ventricular dimensions decrease，and cardiac function progressively recovers. Echocardiography is an essential tool for accurate preoperative assessment and postoperative follow-up in pediatric mitral valve replacement.

In recent years，the incidence and prevalence of non-tuberculous mycobacterial（NTM）infections have been on the rise，posing a serious threat to public health and presenting significant challenges for disease management. Currently，the treatment outcomes for NTM disease are poor，one of the main reasons being the high resistance of NTM pathogens to various anti-mycobacterial drugs. Novel therapeutic strategies targeting the host rather than the NTM pathogens themselves may help improve cure rates and reduce mortality. This article summarizes the latest research findings on host factors related to the incidence of NTM disease，including age，pulmonary diseases，immune function，genetic factors and lifestyle，which aids in the early identification of high-risk populations and provides a theoretical basis for developing targeted prevention and treatment strategies and optimizing treatment plans.

BACKGROUND:Autoimmune regulator gene(Aire)and Wnt signaling pathway play an important role in the maintenance and differentiation of mouse embryonic stem cell pluripotency.However,whether the Wnt signal and Aire are involved in the differentiation of embryonic stem cells to thymic epithelial progenitor cells remains poorly understood. OBJECTIVE:To investigate the relationship of the Wnt signaling pathway and Aire with the differentiation of embryonic stem cells. METHODS:A two-step differentiation method was used to induce mouse embryonic stem cells to differentiate into endoderm and then into thymic epithelial progenitor cells.Mouse embryonic stem cells were infected with Aire shRNA lentivirus,and monoclonal stable strains were screened by puromycin.Mouse embryonic stem cells were collected on days 0,3 and 10 of the directed induction of differentiation after the induced differentiation by the two-step differentiation method.Cellular immunofluorescence,flow cytometry,western blot assay,and real-time qPCR were used to detect the expression changes of related genes and proteins. RESULTS AND CONCLUSION:(1)Immunofluorescence staining showed positive expression of SSEA1 and OCT4 on day 0 of targeted induction of differentiation.(2)Immunofluorescence staining showed double-positive expression of SOX17 and FOXA2 on day 3 of targeted induction of differentiation.(3)Flow cytometry results showed positive expression of EPCAM1,K5 and K8 on day 10 of targeted induction of differentiation.(4)Compared with undifferentiated mouse embryonic stem cells,the expressions of Wnt7a,β-catenin,and Gsk-3β proteins were elevated,and the expression level of Aire protein was decreased in induced differentiated thymic epithelial progenitor cells.(5)Compared with undifferentiated mouse embryonic stem cells,the expressions of Wnt7a,β-catenin,Gsk-3β and Aire mRNA were elevated in thymic epithelial progenitor cells.(6)Compared with normal cultured mouse embryonic stem cells and their ultimately differentiated thymic epithelial progenitor cells,the expression levels of Wnt7a,β-catenin and Gsk-3β proteins were reduced in mouse embryonic stem cells with knockdown of Aire genes and their final differentiated thymic epithelial progenitor cells.In conclusion,the Wnt signaling pathway and Aire are jointly involved in the process of targeted induction of differentiation of mouse embryonic stem cells into mouse thymic epithelial progenitor cells.