Osteoporosis is an emerging threat characterized by systemic damage to bone mass and microarchitecture leading to fragility fractures.Exosomes are nanosized vesicular particles secreted by cells into the extracellular compartment with biological activities similar to those of their cell of origin and play an important role in intercellular communication processes.Exosomes from multiple cell sources are involved in the regulation of bone-related cell proliferation and differentiation during bone metabolism,and have the advantages of high stability,non-immunogenicity and strong targeting ability,which make up for the shortcomings of traditional drug and stem cell therapies.Exosomes secreted from bone marrow mesenchymal stem cells(MSCs)can promote bone regeneration and improve morphology,biomechanics and histological damage,and exosomes derived from bone marrow mesenchymal stem cells(BMSCs)in the mechanical microenvironment are more effective in inducing osteogenesis,significantly enhancing the osteogenic effect of BMSCs and promoting bone regeneration.Therefore,this article provides a review on the mechano-sensitivity of MSCs,mechanical responsive functionalized exosomes of MSCs,and explores their potential role in the treatment of osteoporosis.

Gastric cancer(GC)is one of the most common and high mortality tumors in the world,and the clinical staging during diagnosis is closely related to the prognosis of patients.Therefore,finding sensitive diagnostic biomarkers to improve the early diagnosis rate has become an urgent issue.Exosomes are nanoscale extracellular vesicles secreted by various cells,which play an important role in cellular communication by transporting bioactive substances in tumor microenvironment(TME).CircRNA is a type of non-coding RNA with a specific structure.Because it is difficulty in degradation,it can be enriched in extracellular vesicles and participate in various pathophysiological processes mediated by it.Exo-circRNA can affect the proliferation,invasion,drug resistance and tissue metastasis of tumor cells,and has more significant diagnostic specificity than conventional diagnostic biomarkers in clinical practice.It may become a supplement to biomarker for the diagnosis and prognosis of GC.This article briefly introduces the characteristics,formation mechanism and role of extracellular vesicles and circRNA in GC.It discusses in detail the role of exo-circRNA in the occurrence and development of GC,and discusses their potential clinical application value and challenges in GC.

Objective To explore the diagnostic value of MRI radiomics model for clinically significant prostate cancer(csPCa)in the transition zone with prostate imaging reporting and data system(PI-RADS)3-4.Methods According to the ratio of prostate cancer(PCa)∶benign prostatic hyperplasia(BPH)=1∶1,the relevant data of patients with transition zone lesions confirmed by pathology were retrospectively collected.Patients were divided into csPCa group and non-csPCa group according to pathological results.Region of interest(ROI)were drawn along the edge of the lesion in T2WI,diffusion weighted imaging(DWI),and apparent diffusion coeffi-cient(ADC)sequences,the radiomics features were extracted,and a single sequence logistic regression model was constructed and validated after feature cleaning and screening.The diagnostic performances of the radiomics model for transition zone csPCa were evaluated and compared.Results A total of 204 patients were included,and there were 94 cases in the csPCa group and 110 cases in the non-csPCa group.There were statistically significant differences in PI-RADS,prostate volume(PV),prostate specific antigen(PSA)and its derivative indicators between csPCa and non-csPCa groups.In the validation set,the area under the cunve(AUC)of the ADC model was 0.766,and the DeLong test showed that the diagnostic performance of the ADC model was significantly higher than that of the DWI and T2WI models.Conclusion When the PI-RADS classification of transition zone lesion is 3-4,the ADC radiomics model has good diag-nostic performance for csPCa,which can reduce unnecessary biopsy in some patients.Radiomics is expected to become a more objec-tive and accurate medical diagnostic tool.

Lipedema is a disease in which local fat deposits in the body are the main clinical manifestations. It is often characterized by a disproportionate increase in subcutaneous fat tissue in the extremities, buttocks or hip joints. It is often misdiagnosed as obesity or lymphedema in clinical practice. The pathogenesis is not clearly understood, and there is no standardized clinical treatment method. This paper elaborated on the research status of the pathogenesis of lipedema, and summarized the clinical manifestations and classification, diagnosis and differential diagnosis, treatment methods, etc., aiming to provide up-to-date perspectives of lipedema.

This paper analyzed the "non-standardization" phenomenon of syndrome differentiation in traditional Chinese medicine （TCM） from the diagnosis process. It is proposed that the symptoms and signs collected by the four examinations of inspection， listening/smelling， inquiry， and palpation naturally have a certain "ambiguity"， which can be reduced by the comparison and comprehensive condensation （comprehensive analysis of the four examinations） of a large amount of multi-dimensional clinical data， thereby realizing the sublimation of TCM diagnosis from "ambiguity" of four examinations to "accuracy" of diagnostic conclusion. Based on the above assumptions， this paper further proposed that a research idea of intelligent syndrome differentiation in TCM， that is， by taking the clinical thinking ability of TCM physicians as the core， adopting artificial intelligence technology based on knowledge graph visualization， integrating the complex network association and reasoning method of "symptom-pathogenesis-syndrome" linked by pathogenesis， and through the automatic analysis and reasoning process of a large amount of multi-dimensional and ambiguous clinical data， the intelligent TCM diagnosis based on syndrome differentiation can be realized.

Objective:To explore the optimal index of rotational displacement of femoral neck fractures by modeling the axial rotational displacement of femoral neck fractures after reduction and based on X-ray projections.Methods:Six dry human femur specimens, comprising 2 males and 4 females, were utilized in the study. Design and manufacture a proximal femur ortholateral and oblique X-ray casting jigs and mounts. The femoral neck fracture was modeled on the femoral specimen, with Pauwells 30°, 50°, and 70° models (2 each) made according to Pauwells typing. The fractures were manually repositioned with residual anterior 20°, 40° and 60° axial rotational displacements. Each fracture model was projected at different angles (pedicled 40°, pedicled 20°, vertical 0°, cephalad 20°, and cephalad 40°), and the trabecular angle and Garden's alignment index of the model were measured to observe the imaging characteristics of the fracture line on the medial oblique and lateral oblique radiographs.Results:In the presence of a 20° and 40° anterior rotational displacement following reduction of a femoral neck fracture, the trabecular angle in the rotationally displaced group was not significantly different from that of the anatomically repositioned group in various projection positions. However, when a residual rotational displacement of 60° was present, the trabeculae appeared blurred at most projection angles in the Pauwells 30° and 50° models, failing to measure trabecular angles. In the Pauwells 70° fracture model, the trabecular angle in the rotational displacement group was significantly different from that in the anatomical reduction group. In anteroposterior radiographs, when the anterior rotation displacement was 60° in the Pauwells 70° group, Garden's contralateral index showed an unsatisfactory restoration (150°, 142°), whereas all rotationally displaced models in the Pauwells 30° and Pauwells 50° groups had a Garden's contralateral index of >155°, which achieved an acceptable restoration. In lateral radiographs, all rotational displacement models with Garden's alignment index>180° failed to achieve acceptable repositioning, and the larger the Pauwells angle the greater the Garden's alignment index at the same rotational displacement. In the internal oblique position with a bias towards the foot side, the image showed partial overlap between the femoral head and the shaft, making it difficult to assess the quality of the reduction. Conversely, when projected cephalad, the femoral neck appeared longer, particularly at a projection angle of 40° cephalad, allowing for clear observation of the fracture line and the anatomy of the proximal femur. The trabeculae were not well visualized in the external oblique position.Conclusion:There are limitations in applying the trabecular angle to assess the axial rotational displacement of the femoral head after reduction of femoral neck fractures. The Pauwells 70° with residual rotational anterior displacement of 60° was the only way to detect axial rotational displacement of the femoral head on anteroposterior radiographs Garden's alignment index. For the determination of axial rotational displacement of the femoral head, the Garden's alignment index on lateral radiographs provides higher reliability.

Examining mechanisms involved in the mutual regulation between the muscular system and the skeletal system, elucidating the key issues responsible for loss of muscle and bone mass and strength, and thus halting the progression of these conditions are critical measures for reducing fractures caused by falls and subsequent disability and mortality.At present, most studies have treated the muscular system and the skeletal system separately, often ignoring the mutual regulation and connections between them.This article reviews the current research progress on the mechanisms of interaction between the two systems, aiming to provide a basis for the prevention, diagnosis and treatment of disuse-related diseases in the elderly population.

Lipedema is a disease in which local fat deposits in the body are the main clinical manifestations. It is often characterized by a disproportionate increase in subcutaneous fat tissue in the extremities, buttocks or hip joints. It is often misdiagnosed as obesity or lymphedema in clinical practice. The pathogenesis is not clearly understood, and there is no standardized clinical treatment method. This paper elaborated on the research status of the pathogenesis of lipedema, and summarized the clinical manifestations and classification, diagnosis and differential diagnosis, treatment methods, etc., aiming to provide up-to-date perspectives of lipedema.

As a deubiquitinating enzyme with important biological functions,Mysm1 has become a significant regulatory factor affecting the functions of various stem cells,immune responses and occurrence and development of multiple diseases.Studies have found that the sequences of mouse and human Mysm1 are highly homologous,both Mysm1 knockout mice and patients with Mysm1 gene mutations exhibit developmental disorders in multiple tissues and organs.Therefore,in-depth analysis of Mysm1 function in mouse models is critical to the etiological study of human Mysm 1-related syndromes.This article reviewed the various deubiquitinating functions of Mysm 1 in the nucleus or cytoplasm,its impact on the proliferation and differentiation of various stem cells and immune cell functions,its role in the occurrence and development of diseases such as cancer,aging and depression in hopes of providing a reference for in-depth research on Mysm1 in the future.

As the National Health Commission changes the management of novel corona virus infection, the situation and preventive policies for controlling the epidemic have also entered a new stage in China. Perioperative care strategies for orthopedic trauma such as designated isolation and nucleic acid test screening have also been adjusted in the new stage. Based on the perioperative work experiences in the new stage of epidemic from the frontline anti-epidemic staff of orthopedics in domestic hospitals and combined with the literature and relevant evidence-based medical data in perioperative care of orthopedic trauma patients under the current anti-epidemic policies at home and abroad, Chinese Orthopedic Association and Chinese Society of Traumatology organized relevant experts to formulate the Guideline for clinical perioperative care of orthopedic trauma patients in the new stage of novel corona virus infection ( version 2023). The guideline summarized 16 recommendations from the aspects of preoperative diagnosis and treatment, infection prevention, emergency operation and postoperative management to systematically standardize the perioperative clinical pathways, diagnosis and treatment processes of orthopedic trauma in the new stage of novel corona virus infection, so as to provide a guidance and reference for hospitals at all levels to carry out relevant work in current epidemic control policies.