BACKGROUND:Exosomes derived from mesenchymal stem cells play pivotal roles in cell communication and epigenetic regulation due to their low immunogenicity and targeted delivery effects,and have been clinically applied in the treatment of various diseases.OBJECTIVE:To review the isolation,purification,identification methods,and application progress of mesenchymal stem cell-derived exosomes,and to facilitate the development of large-scale preparation techniques and clinical translation of mesenchymal stem cell-derived exosomes.METHODS:The Chinese search terms"exosome,mesenchymal stem cells,isolation,purification,characterization,clinical application"and the English search terms"exosome,extracellular vesicles,mesenchymal stem cells,isolation,characterization,application"were used to search the literature published before September 2024 in CNKI,PubMed,and Web of Science databases.Articles with poor relevance to the topic,outdated,or duplicated content were excluded,and finally,109 articles were included for review.RESULTS AND CONCLUSION:(1)This paper reviews recent methods for isolating and purifying exosomes,comparing the characteristics of ultracentrifugation,ultrafiltration,size-exclusion chromatography,polymer precipitation,immunoaffinity,microfluidic methods,and other novel approaches based on their underlying principles.(2)Methods for identifying exosomes can be categorized into physical and biochemical analyses,characterizing exosomes based on their shape,size,and characteristic proteins.(3)Mesenchymal stem cell-derived exosomes have broad applications in multiple fields such as medical aesthetics,wound repair,and cancer treatment,due to their immune-regulatory properties and ability to cross biological barriers.(4)The clinical translation of exosomes faces challenges due to their complex structure,lack of universal isolation techniques,and poor stability,making it difficult to achieve in a short period of time.

BACKGROUND:Bone tissue loss caused by tumors and trauma can have an adverse effect on postoperative rehabilitation.Therefore,scaffold materials are usually implanted during treatment.However,the existing implant materials are relatively simple and lack antibacterial properties.Early implantation may lead to iatrogenic autoinfection and have an adverse effect on osteogenesis.OBJECTIVE:To construct a KR-12-a5 polypeptide-nanohydroxyapatite-small intestinal submucosa composite scaffold and evaluate its feasibility as a material for promoting bone defect repair.METHODS:The small intestinal submucosa scaffold and the small intestinal submucosa scaffold containing 25,50,and 100 mg/mL nanohydroxyapatite(referred to as nHA-SIS scaffold)were prepared by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride/N-hydroxysuccinimide cross-linking method.The appropriate scaffold was screened for subsequent experiments by mechanical property testing.The antibacterial properties of KR-12-a5 polypeptide solution against Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum were detected.The nHA-SIS scaffolds were immersed in 250,500,and 1 000 μg/mL KR-12-a5 peptide solutions for 24 hours,and then freeze-dried to obtain peptide-loaded nanohydroxyapatite-porcine small intestinal submucosa composite scaffolds(denoted as P-nHA-SIS scaffolds).The sustained-release properties of the three groups of scaffolds were characterized.The nHA-SIS scaffolds and the three groups of P-nHA-SIS scaffolds were co-cultured with Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum for 24 hours or 48 hours.The scaffolds with strong antibacterial ability were screened by live and dead bacteria staining and scanning electron microscopy for subsequent experiments.The degradation properties and water absorption rates of the uncross-linked small intestinal submucosa scaffolds,cross-linked small intestinal submucosa scaffolds,nHA-SIS scaffolds,and P-nHA-SIS scaffolds were characterized.The extracts of cross-linked small intestinal submucosal scaffolds,nHA-SIS scaffolds,and P-nHA-SIS scaffolds were co-cultured with MC3T3-E1 cells.CCK-8 assay and live-dead cell staining were performed.The effects of the extracts of the three scaffolds on the migration of MC3T3-E1 cells were detected by Transwell chamber assay.RESULTS AND CONCLUSION:(1)The elastic modulus and compressive strength of 25,50,and 100 mg/mL nHA-SIS scaffolds were higher than those of small intestinal submucosal scaffolds(P＜0.05),among which the elastic modulus and compressive strength of 25 mg/mL nHA-SIS scaffolds were the highest,and this group of scaffolds were selected for subsequent experiments to load peptides.(2)KR-12-a5 peptide had strong antibacterial activity against common bacteria in bone defects(Staphylococcus aureus,Streptococcus gordonii,and Fusobacterium nucleatum).The three groups of P-nHA-SIS scaffolds all had sustained release properties.With the increase of peptide mass concentration,the antibacterial property of P-nHA-SIS scaffold was enhanced.Among them,the P-nHA-SIS scaffold loaded with 500 μg/mL peptide had achieved a satisfactory antibacterial effect,and this group of scaffolds would be selected in the future.(3)The degradation rate of the three groups of cross-linked scaffolds was lower than that of the uncross-linked scaffolds,and the water absorption rate was greater than that of the uncross-linked scaffolds.P-nHA-SIS scaffolds could promote the proliferation and migration of MC3T3-E1 cells without affecting the activity of MC3T3-E1 cells.(4)The results show that P-nHA-SIS scaffolds have strong antibacterial properties and the ability to promote the proliferation and migration of MC3T3-E1 cells,and are expected to be used in bone defect repair.

BACKGROUND:Hydrogen peroxide-based bleach is widely used in clinical tooth whitening treatment,but its mechanism of action has not been uniformly determined so far.OBJECTIVE:To examine the effects of two bleaching agents,neutral 10％carbamide peroxide and neutral 40％hydrogen peroxide,on teeth and explore the mechanism of teeth whitening.METHODS:Forty-five discarded teeth extracted for orthodontic treatment were collected,and the dentin sections were made and polished.After removing the smear layer,they were randomly divided into three groups.The control group(n=15)was placed in deionized water;the carbamide peroxide group(n=15)was placed in a neutral 10％carbamide peroxide solution,and the hydrogen peroxide group(n=15)was placed in a neutral 40％hydrogen peroxide solution.The treatment was continued for 6 hours every day for 1 week.The Raman absolute intensity and Raman relative intensity of the three groups of samples were detected by Raman spectrometer every day,and the fluorescence background intensity(the difference between the Raman absolute intensity and the Raman relative intensity)was calculated.The change trend of the amide peak of the three groups of samples every day was recorded by infrared spectrometer.RESULTS AND CONCLUSION:(1)The relative Raman intensity of the three groups did not change significantly during the 1-7 days of treatment.The fluorescence background intensity of the control group did not change significantly during the 1-7 days of treatment.The fluorescence background intensity of the carbamide peroxide group showed a downward trend during the 1-7 days of treatment.The fluorescence background intensity of the hydrogen peroxide group decreased significantly during the 1-4 days of treatment and did not change significantly thereafter.(2)The peak areas of amide Ⅰ and amide Ⅲ did not change significantly during the 1-7 days of treatment in the control group.The peak areas of amide Ⅰ and amide Ⅲ showed a downward trend during the 1-7 days of treatment in the carbamide peroxide group and the hydrogen peroxide group,and the downward trend was more obvious in the hydrogen peroxide group.(3)The results show that the change in the laser-induced fluorescence background intensity of dentin Raman spectroscopy may be derived from the non-collagen components in dentin,and under the action of whitening agents,it may have a certain adverse effect on tooth tissue.

BACKGROUND:Inter-limb asymmetry is a common phenomenon observed during human growth and development.Prolonged specialized training can lead to specific adaptations in inter-limb asymmetry among athletes.OBJECTIVE:To review the formation causes,manifestations,and impacts of inter-limb asymmetry on sports performance,and provide an overview of the relevant assessment methods and intervention strategies.METHODS:A literature search was conducted in the CNKI,WanFang,PubMed,and Web of Science databases from their inception to September 2024.The search terms included"asymmetry,asymmetries,asymmetric,asymmetrical,imbalance,strength,power,force,jump,sprint,athletic performance,anthropometry,injury"in English and Chinese.After excluding duplicate publications,irrelevant content,and conference papers,a total of 131 articles were finally included for analysis.RESULTS AND CONCLUSION:(1)Inter-limb asymmetry can be influenced by various factors including genetics,task demands,training regimens,injuries,fatigue,and limb preference.These factors lead to being primarily manifested in anatomical structure,strength performance,and task-specific asymmetry.(2)An increase in inter-limb asymmetry can result in impaired performance in bilateral in-phase symmetric movements.However,the relationship between increased inter-limb asymmetry and bilateral out-of-phase symmetric movements remains unclear and requires further investigation.(3)Training interventions have been shown to effectively mitigate inter-limb asymmetry,with unilateral training demonstrating superior outcomes compared with bilateral training.The choice of training methods and content should be tailored to meet the specific demands of the sport.(4)To further clarify the relationship between inter-limb asymmetry and athletic performance,it is recommended that future research adopt the concept of"task specificity"in inter-limb asymmetry.This includes standardizing study designs,selecting sensitive testing methods and indicators,unifying calculation methods to provide more high-quality evidence,and establishing categorized warning threshold standards for inter-limb asymmetry in different sports.

The prescription of Qidong Yixin oral liquid is derived from the experience of national medical master Ren Jixue in treating viral myocarditis （VMC）. It has the functions of tonifying Qi， nourishing the heart，calming the mind， and relieving palpitations. It is used to treat VMC and angina pectoris of coronary heart disease caused by deficiency of both Qi and Yin. However，the understanding of its efficacy evidence， advantageous aspects， dosage and administration， and medication safety remains insufficient in clinical practice. Therefore，the development of the Expert Consensus on the Clinical Application of Qidong Yixin Oral Liquid （hereinafter referred to as consensus） was initiated. Consensus strictly followed the process and methods of the expert consensus on the clinical application of Chinese patent medicines of the China Association of Chinese Medicine，successively completing multiple tasks such as the consensus project initiation，determination of clinical problems，evidence search and evaluation，formation of recommendation opinions and consensus suggestions，solicitation of opinions，peer review， submission for review and release， and so on. Consensus formed a total of 10 recommendation opinions and 12 consensus suggestions，clarifying the clinical positioning，efficacy advantages，syndrome differentiation，dosage and administration，combination therapy，timing of medication，adverse reactions，contraindications， and precautions of Qidong Yixin oral liquid，indicating that it has good clinical advantages and safety in the treatment of VMC and angina pectoris of coronary heart disease，providing norms and references for physicians to safely and rationally apply Qidong Yixin oral liquid. Consensus was reviewed and approved for release by the Standardization Office of the China Association of Chinese Medicine on December 23， 2024. Standard number：GSCACM-376-2024.

Breast cancer （BC）， a common malignant tumor in women， is characterized by high incidence and mortality rates， posing a serious threat to women's life and health. Currently， the commonly used treatments for BC include surgery， radiotherapy， chemotherapy， molecular targeted therapy， and endocrine therapy. Although radiotherapy and chemotherapy can effectively kill tumor cells and inhibit the proliferation and differentiation of tumor cells， they can induce adverse reactions such as hematopoietic dysfunction and impaired immune function. The other treatment methods also have problems such as drug resistance， high recurrence rates， reduced quality of life， and poor clinical efficacy. Therefore， it is urgent to explore new drugs with better efficacy and lower toxicity. Ferroptosis is a form of iron-dependent， non-apoptotic programmed cell death triggered by lipid peroxidation. In recent years， ferroptosis has become a hot topic in the field of cancer treatment and has been gradually proven to effectively inhibit the proliferation and metastasis of BC cells， reduce the drug resistance of BC to chemotherapy drugs， and enhance the sensitivity of BC to radiotherapy. Traditional Chinese medicine （TCM）， with multiple components， multiple targets， and mild side effects， is widely used in the treatment of BC. A large number of studies have shown that active ingredients of TCM， such as saponins， flavonoids， terpenoids， phenols， and polysaccharides， can inhibit the proliferation and metastasis of BC cells by modulating ferroptosis-related pathways. These include iron metabolism， lipid metabolism， cystine/glutamate antiporter system Xc^-/glutathione/glutathione peroxidase 4， Specifically， these ingredients elevate the levels of lipid peroxidation， reactive oxygen species， malondialdehyde， and Fe²⁺ in BC cells， thereby inducing ferroptosis-mediated suppression of tumor progression. This article reviews the relevant literature at home and abroad in recent years， summarizes the mechanisms of ferroptosis in regulating BC and the research progress in the active components of TCM targeting ferroptosis in the intervention of BC， aiming to provide ideas for the development of new drugs for the treatment of BC.

To investigate the changes in peripheral blood immune cells before and after the onset of septic shock in patients with malignant tumors, and to analyze the relationship between these immune cells and patient prognosis.

To develop and validate a model for predicting intensive care unit (ICU) mortality risk in patients with malignant tumors complicated by acute respiratory failure (ARF) based on an explainable machine learning framework.

This paper summarizes Professor DING Ying's clinical experience in the treatment of systemic lupus erythematosus （SLE） through differentiation of three states， yin fire， latent fire， and fire toxin. It is proposed that fire pathogenic factors constitute a key pathological element running throughout the entire disease course of SLE. The evolution of its pathogenesis centers on these three states， spleen-kidney deficiency with the initial emergence of yin fire as the onset of disease， damage to yin by medicinal toxicity with internal blazing of latent fire as the driver of disease progression， and the interlocking of blood stasis and heat with intense scorching by fire toxin as the critical factor leading to severe and life-threatening conditions. Corresponding to these three stages， targeted prescriptions are formulated， Jiuwei Yishen Formulation （九味益肾方） to tonify the spleen and kidney， raise yang， and disperse fire； Ziyin Xiehuo Decoction （滋阴泄火汤） to nourish yin and fluids while clearing latent fire； and Santeng Changluo Jiedu Decoction （三藤畅络解毒汤） to dispel blood stasis， unblock the collaterals， detoxify， and restrain fire. This staged and integrated therapeutic strategy aims to address both root and branch and to achieve overall regulation， providing valuable guidance for the clinical differentiation and treatment of SLE.

Objective To study the five-year survival status and influencing factors of elderly patients with lung cancer complicated with chronic obstructive pulmonary disease (COPD). Methods A cohort study was conducted to follow up 450 patients with lung cancer and chronic obstructive pulmonary disease who were hospitalized in our hospital from January 2018 to December 2023. The endpoint of the follow-up was the end of a five-year period or death. The Life Tables method was used to calculate survival rates and plot survival curves. The Cox proportional hazards model was used to analyze the influencing factors of five-year survival. Results The results indicated that the overall five-year survival rate of patients was 4.89%, and it decreased year by year. Cox regression analysis showed that age, gender, family functioning, and psychological status significantly influenced patient survival rate (all P<0.05). Stratified analysis found that the smoking status, family functioning, and psychological status of male patients all had an impact on survival rate (all P<0.05), while the psychological status of female patients had a more significant impact on survival (P=0.008). Conclusion This study provides a scientific basis for comprehensive intervention of elderly lung cancer patients with COPD. It is recommended that clinical attention should be paid to psychological and family factors to improve patient prognosis.