OBJECTIVE To investigate the current status of cleaning and disinfection of medical bedding items in public medical institutions of Liangshan ethnic minority area and analyze the risk of infections so as to provide ba-ses for optimizing the infection control strategies in the ethnic minority area.METHODS On the basis of question-naire survey,onsite sampling method and bacterial isolation and identification technique,a cross-sectional survey was conducted for the current status of cleaning and disinfection of medical bedding items in 15 different grades of public medical institutions of Liangshan ethnic minority area by stratified random sampling method from Sep.2021 to Sep.2023.RESULTS A total of 66 valid questionnaire were recycled,and 540 bedding item samples were col-lected.Totally 93.33％of the medical institutions relied on laundries for centralized cleaning of the medical bed-ding items.The implementation rates of management items such as policy formulation(100.00％)and pre-job training were remarkably higher in the tertiary hospitals than in the secondary and primary hospitals(allP＜0.05).There were no significant differences in the qualified rates of surveillance of microbiological indexes for the medical bedding items among the medical institutions,the qualified rate of surveillance of microbiological inde-xes was highest(71.30％)in the general hospitals and was lowest(61.11％)in the infectious diseases specialized hospital.The qualified rate of surveillance of microbiological indexes was lowest(3.33％)in pediatrics department or internal medicine department,and it raised most remarkably(80.00％)after the disinfection,and there was significant difference(x2=36.274,P＜0.001).CONCLUSIONS The current status of disinfection of the medical bedding items is not optimistic in the medical institutions of Liangshan ethnic minority area.There are the prob-lems such as imperfect system,insufficient equipment and absence of personnel training.It is necessary to com-plete the execution and supervision system for cleaning and disinfection standards,increase the cleaning facilities,promote the use of antibacterial textile and bring in smart management system so as to improve the cleaning and disinfection quality and reduce the risk of hospital-associated infections.

BACKGROUND:Extracellular vesicles have received extensive attention in the field of bone defect regeneration and repair in recent years.However,natural extracellular vesicles have deficiencies in sustained controlled release,tissue targeting,and drug loading capacity.Therefore,the introduction of engineering strategies to modify extracellular vesicles to enhance their therapeutic efficacy has become a research hotspot.OBJECTIVE:To review the role and application progress of engineered extracellular vesicles in the regeneration and repair of bone defects.METHODS:PubMed,Web of Science,CNKI,and WanFang databases were searched for relevant articles published in the past fifteen years.The search terms were"engineering,extracellular vesicles,exosomes,bone defect,bone regeneration,bone repair"in Chinese and English.After removal of poorly related,outdated,and duplicate studies by screening,93 articles were finally included for review according to inclusion criteria.RESULTS AND CONCLUSION:(1)Extracellular vesicles are primarily isolated based on their density,size,immunoaffinity,and surface charge.After isolation,extracellular vesicles are characterized using imaging techniques,size-and counting-based techniques,and flow cytometry.(2)Extracellular vesicles stimulate bone regeneration by regulating immunity,angiogenesis,and proliferation and differentiation of target cells.(3)The engineering strategies of extracellular vesicles include surface modification and cargo loading.(4)The introduction of bone morphogenetic protein 2,mutant hypoxia-inducible factor-1α,vascular endothelial growth factor,miRNA and other bioactive factors into extracellular vesicles through engineering strategies can enhance their regenerative repair ability for bone defects.

Objective:To explore the relationship between maternal rejection and internet addiction in college students, as well as the chain mediating role of rejection sensitivity and adaptability.Methods:From March to May 2024, a total of 1 119 college students were surveyed using the short-form Egna Minnen av Barndoms Uppforstran for Chinese(s-EMBU-C), internet addiction test(IAT), rejection sensitivity questionnaire(RSQ), and the China college student adjustment scale(CCSAS).SPSS 26.0 statistical software was used for independent sample t-test, one-way ANOVA, Pearson product moment correlation, and multiple linear regression analysis, and PROCESS 4.0 macro program was used for chain mediation analysis. Results:(1)Maternal rejection (11.19±2.97) was positively correlated with internet addiction (44.89±9.74)( r=0.60, P<0.01) and rejection sensitivity (102.93±55.63)( r=0.63, P<0.01), while negatively correlated with adaptability (200.19±14.18)( r=-0.56, P<0.01) among college students. Rejection sensitivity was positively correlated with internet addiction ( r=0.75, P<0.01) and negatively correlated with adaptability ( r=-0.76, P<0.01). Adaptability was negatively correlated with internet addiction ( r=-0.68, P<0.01). (2)Maternal rejection had a significant direct effect on internet addiction among college students (effect value=0.193, 95% CI=0.145-0.241), accounting for 32.06%(0.193/0.602) of the total effect. Rejection sensitivity mediated the relationship between maternal rejection and internet addiction (effect value=0.290, 95% CI=0.232-0.357), accounting for 48.17%(0.290/0.602) of the total effect. Adaptability also mediated this relationship (effect value=0.028, 95% CI=0.009-0.053), accounting for 4.65%(0.028/0.602) of the total effect. Additionally, there was a chain mediation effect of rejection sensitivity and adaptability on the relationship between maternal rejection and internet addiction (effect value=0.091, 95% CI=0.052-0.130), accounting for 15.12%(0.091/0.602) of the total effect. Conclusion:Maternal rejection can directly influence internet addiction in college students, and it can also indirectly influence internet addiction through the independent mediating effects of rejection sensitivity and adaptability, as well as through the chain mediating effects of both rejection sensitivity and adaptability.

Objective:To explore the effects of perceived stress on ego depletion of college students, as well as the mediating role of emotional eating and the moderating role of peer relationship.Methods:A cross-sectional survey of 1 088 college students was conducted using the perceived stress scale, the Dutch eating behavior questionnaire, the self-control resource depletion scale, and the peer relationship measurement from December 2023 to April 2024.PROCESS Macro program in SPSS 25.0 software was used to test the mediating effect of emotional eating and the moderating effect of peer relationship.Results:(1)The score of perceived stress, emotional eating, peer relationship and ego depletion were 39.26±8.35, 39.19±12.15, 2.00(1.00), and 18.19±7.15, respectively.(2)Perceived stress was positively correlated with emotional eating, ego depletion, and peer relationship( r=0.36, 0.61, 0.25, all P<0.01). Emotional eating was positively correlated with ego depletion and peer relationship( r=0.40, 0.19, both P<0.01). And ego depletion was positively correlated with peer relationship( r=0.23, P<0.01).(3)Emotional eating played a partial mediating role in the effect of perceived stress on ego depletion( β=0.077, 95% CI=0.053-0.104), and the mediating effect accounted for 12.38%(0.077/0.622) of the total effect.(4)Peer relationship played a moderating role between perceived stress and emotional eating. Under low peer relationship, perceived stress had a significant positive predictive effect on emotional eating( βsimple=0.46, P<0.01), and under high peer relationship, the predictive effect of perceived stress on emotional eating was significantly weaker( βsimple=0.26, P<0.01). Conclusions:Perceived stress not only directly affects ego depletion, but also indirectly affects ego depletion through emotional eating in college students.High levels of peer relationship can weaken the impact of perceived stress and high emotional eating on ego depletion.

Objective:To investigate the characteristics of m6A methylation modification patterns in mRNA of patients with major depressive disorder (MDD) and its effect in the pathogenesis of the disease.Methods:From March 2022 to May 2023, five untreated MDD patients were assigned to the MDD group, and five healthy individuals were enrolled as the healthy control group at the First Psychiatric Hospital of Harbin.Microarray analysis was performed to determine the m6A modification profiles and gene expression patterns of mRNA in MDD. Gene ontology (GO) enrichment analysis and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis were conducted to elucidate the effect of m6A methylation in the development of depression. Finally, methylated RNA immunoprecipitation combined with quantitative PCR (MeRIP-qPCR) was used to validate the m6A methylation levels of key mRNAs (GRM4, CAMKK2). Data were analyzed using R software (version 4.2.0) with t-test and Fisher's exact test. Results:Significant differences in m6A-modified mRNAs were observed between MDD patients and healthy controls. A total of 513 mRNAs (180 hypermethylated and 333 hypomethylated) exhibited differential m6A modifications in MDD patients. GO and KEGG analysis revealed that hypermethylated mRNAs were primarily enriched in neuroactive ligand-receptor interactions, while hypomethylated mRNAs were associated with the AMP-activated protein kinase (AMPK) signaling pathway. Additionally, a total of 350 differentially expressed mRNAs were identified (171 upregulated and 179 downregulated), enriched in the cyclic adenosine monophosphate (cAMP) and tumor necrosis factor (TNF) signaling pathways. MeRIP-qPCR results demonstrated that the m6A methylation level of GRM4 in MDD patients (25.40±2.38) was significantly higher than that in healthy controls (9.40±1.00) ( t=13.88, P<0.05), whereas the methylation level of CAMKK2 (19.63±6.60) was significantly lower than that in healthy controls (30.51±7.20) ( t=2.48, P<0.05). Conclusion:The m6A modification expression profile is abnormal in patients with major depressive disorder, which may be involved in the pathogenesis and development of MDD, and the identification of key pathways may provide new clues and evidence for the development of more effective therapeutic targets for MDD.

Objective To evaluate the clinical outcome of posterior cruciate ligament(PCL)recon-struction using ligament augmentation and reconstruction system(LARS)artificial ligament,and ana-lyze factors affecting the prognosis.Methods A total of 45 patients(31 males and 14 females,with an average age of 38.0±12.8 years)underwent PCL reconstruction using LARS artificial ligament in China-Japan Friendship Hospital in years from 2018 to 2021 were analyzed retrospectively.Their aver-age time from injury to surgery of 2.8±4.2 months.They were followed up for no less than 1 year about the stability of knee,Lysholm score and Tegner score,as well as the patient's satisfaction.Moreover,the effect of patient's age,time from injury to surgery,and complications of other ligament injuries of the knee on the final outcomes were analyzed.Results For all the 45 patients,the mean follow-up time was 35.0±14.1 months,with their satisfaction rate of 91.1%.There were 31 cases of 3° instability and 14 cases of 2° instability before surgery,which improved significantly as only 4 cas-es were of 2° instability,22 cases of 1° instability at the final follow-up(χ2=77.56,P<0.000).More-over,the average Lysholm and Tegner scores increased significantly from 37.2±15.2 and 0.9±0.9,to 85.3±12.7 and 4.4±1.3,respectively(t=16.34,P<0.000;t=15.72,P<0.000).What's more,the age of over 40 years had effect on the prognosis,while the time from injury to surgery and the com-plicated ligament injuries of the knee did not.Conclusion Using LARS artificial ligament as graft for PCL reconstruction can achieve satisfactory clinical results on the short-term.

Plastics are widely used in all areas of human life,providing convenience while also causing serious en-vironmental pollution problems.Microplastic pollution is one of its derivative problems.Microplastics are plastic parti-cles with a diameter of less than 5 mm.They are currently widely present in the environment,so humans are at considera-ble risk of exposure to microplastics.Humans are mainly exposed to microplastics through the respiratory tract,digestive tract and skin.When exposed to a large number of microplastics,some of them will enter the body and be transported throughout the body via the bloodstream,accumulating in multiple tissues and organs.A significant amount of microplas-tics has also been detected in the cardiovascular system.This paper systematically describes human exposure to and dam-age by microplastics,highlighting the distribution and pathological damage of microplastics in the cardiovascular system.The pathological mechanisms of cardiovascular damage caused by microplastics are analyzed,and relevant clinical research progress is followed.This paper aims to evaluate the pathological risk of microplastics from the perspective of cardiovascu-lar damage,and provide a basis for disease prevention and scientific prevention and control of microplastic pollution.

Objective To investigate the correlation between changes in physiological indicators and altitude,age,and sex among ethnic Tibetan college students living in Xizang on long-term basis upon their first ever visit to a low-altitude region,thereby providing health guidance for long-term residents of high-altitude regions when they visit low-altitude environments for the first time.Methods A cluster random sampling method was used to select 170 healthy first-year college students of Tibetan ethnicity(85 males and 85 females),from Xizang Minzu University.The participants did not have any respiratory,circulatory,or nervous system diseases,nor any family history of such conditions.Based on their responses to questionnaires and the monitoring data of their physiological indicators,an analysis was conducted to assess the incidence and duration of deacclimatization symptoms among these Tibetan college students during the first month after their arrival at a low-altitude region.In addition,the R programming language and the SPSS software were used to analyze the correlation between changes in blood pressure,heart rate,and body weight and the participants'age,sex,and the altitude of their long-term residence in Xizang before and after their arrival at a low-altitude region.Results Statistical analysis revealed that Tibetan college students experienced deacclimatization symptoms within the first week of their first ever visit to a low-altitude region,primarily characterized by dizziness,fatigue,and drowsiness.The incidence was 41.9％among female students and 22.5％among male students.Furthermore,after arriving at low-altitude region,the participants experience an initial decrease followed by a recovery in both blood pressure and heart rate.They gained an average of 1.5 kg in body mass compared with their initial measurements upon arrival in a low-altitude region.Significant differences in blood pressure,heart rate,and body mass were observed among Tibetan students of different sexes and altitudes of their long-term residence in Xizang after their arrival in a low-altitude region.Conclusion After arriving at a low-altitude region,Tibetan college students exhibit marked changes in physiological indicators,showing strong correlations between systolic blood pressure,body mass,etc.,and sex,altitude,and other parameters.

Objective:To analyze the clinical characteristics and cytokines expression characteristics in infants with mild and severe respiratory syncytial virus (RSV) infection.Methods:From May 2023 to December 2023, plasma samples and clinical information were collected from 16 infants with RSV infection and 14 control infants. Cytek Aurora flow cytometry (Cytek, America) and Enzyme linked immunosorbent assay (ELISA) were used to detect the expression levels of 25 cytokines after mild and severe RSV infection.Results:Cough and nasal obstruction were the main clinical manifestations in infants with mild RSV infection, accompanied by polypnea, wheezing and other symptoms. The main symptoms of severe RSV infection were cough and rales, accompanied by fever and polypnea. In comparison with the control group, the expression levels of IL-2, IL-4, IL-5, IL-6, IL-9, IL-13, IL-22, TNF-α, IFN-α, IFN-β, MIP-1β, I-TAC, ENA-78, GROα, Eotaxin, and MCP-1 in the RSV infection group all exhibited an upregulation trend. Both IP-10 and MIP-3α demonstrated a downward trend in the RSV infection group; however, there was no statistically significant difference ( P>0.05). The levels of IL-10, IFN-γ, MIP-1α, and IL-8 in the RSV infection group were significantly higher than those in the control group, whereas the levels of MIG, TARC, and RANTES in the RSV infection group were significantly lower than those in the control group ( P<0.05). The levels of IL-2, IL-4, IL-5, IL-6, IL-9, IL-10, IL-13, IL-22, IFN-β, IFN-γ, TNF-α, IL-8, I-TAC, MIP-1β, Eotaxin, and MCP-1 in the mild RSV infection group were significantly higher than those in the severe RSV infection group ( P>0.05). Among these, the levels of MIG, RANTES, TARC, MIP-3α, and ENA-78 in the mild infection group were all lower than those in the severe infection group. The expressions of ENA-78 and MIP-1α in the severe infection group were significantly higher than those in the mild infection group and also higher than those in the control group. There was no significant difference in IP-10 and GROα between the mild and severe RSV infection groups ( P>0.05). Conclusions:The differences in clinical features and cytokines between infants with mild and severe RSV infection provide important data support for the prevention and treatment of RSV infection in infants.

OBJECTIVE To investigate the current status of cleaning and disinfection of medical bedding items in public medical institutions of Liangshan ethnic minority area and analyze the risk of infections so as to provide ba-ses for optimizing the infection control strategies in the ethnic minority area.METHODS On the basis of question-naire survey,onsite sampling method and bacterial isolation and identification technique,a cross-sectional survey was conducted for the current status of cleaning and disinfection of medical bedding items in 15 different grades of public medical institutions of Liangshan ethnic minority area by stratified random sampling method from Sep.2021 to Sep.2023.RESULTS A total of 66 valid questionnaire were recycled,and 540 bedding item samples were col-lected.Totally 93.33％of the medical institutions relied on laundries for centralized cleaning of the medical bed-ding items.The implementation rates of management items such as policy formulation(100.00％)and pre-job training were remarkably higher in the tertiary hospitals than in the secondary and primary hospitals(allP＜0.05).There were no significant differences in the qualified rates of surveillance of microbiological indexes for the medical bedding items among the medical institutions,the qualified rate of surveillance of microbiological inde-xes was highest(71.30％)in the general hospitals and was lowest(61.11％)in the infectious diseases specialized hospital.The qualified rate of surveillance of microbiological indexes was lowest(3.33％)in pediatrics department or internal medicine department,and it raised most remarkably(80.00％)after the disinfection,and there was significant difference(x2=36.274,P＜0.001).CONCLUSIONS The current status of disinfection of the medical bedding items is not optimistic in the medical institutions of Liangshan ethnic minority area.There are the prob-lems such as imperfect system,insufficient equipment and absence of personnel training.It is necessary to com-plete the execution and supervision system for cleaning and disinfection standards,increase the cleaning facilities,promote the use of antibacterial textile and bring in smart management system so as to improve the cleaning and disinfection quality and reduce the risk of hospital-associated infections.