BACKGROUND:In recent years,there has been an explosion of research in the field of physical activity and cognition of older adults,and the research hotspots and topics in this field are constantly evolving.However,a comprehensive review of the literature in this field is lacking. OBJECTIVE:To explore the current international research hotspots and contents in the field of physical activity and cognition of older adults using bibliometrics. METHODS:The Web of Science Core Collection Database,including SCI-EXPANDED,SSCI,A&HCI,CPCI-S,CPCI-SSH,BKCI-S,BKCI-SSH,ESCI,CCR-EXPANDED,IC,etc.,was searched for relevant literature in English.CiteSpace software was used to visualize and analyze 2593 documents collected in the Web of Science database. RESULTS AND CONCLUSION:The evolution of the topics of physical activity and cognition of older adults includes five stages:research on companion robots for older adults,research on the risk of diseases such as dementia,research on cognitive ability and its related ability,research on the relationship between physical activity level and cognitive ability in older adults,and research on different intervention methods and their mechanisms.The research in this field tends to be diversified.On the basis of the research on diseases and cognitive risk reduction,more attention has been paid to the effects of different physical activity modalities on cognition and the related mechanisms,which is the current research hotspot and will be the main research trend in the future.

Objective To investigate the effect of aerobic exercise preconditioning on cardiac function in mice bearing subcutaneous transplantable tumors and explore the potential molecular mechanisms.Methods Twenty-four 6-week-old male BALB/c mice were selected.After an acclimation period,they were randomly assigned to a control group(C),a tumor group(M)and an exercise-preconditioning plus tumor group(EM),each of eight.The EM group underwent a 4-week aerobic exercise interven-tion.Meanwhile,the C group received 0.2 ml of physiological saline injected subcutaneously on the dorsum of the proximal left hind limb,while the M and EM groups were inoculated at the same site with 0.2 ml of a CT26.WT colon carcinoma cell suspension.Three weeks after inoculation,cardiac function was assessed by transthoracic echocardiography.Hearts were then harvested for hematoxylin-eo-sin staining to evaluate cardiomyocyte cross-sectional area(CSA),while Western blot was performed to determine the expression of proteins related to myocardial protein synthesis and degradation.Results(1)Compared with group C,group M exhibited significantly lower body weight and heart weight(P<0.05),and reduced left ventricular ejection fraction(LVEF),fractional shortening(FS)and stroke vol-ume(SV)(P<0.05),as well as cardiomyocyte CSA(P<0.01)and total mTOR(P<0.01),phosphory-lated mTOR(p-mTOR)(P<0.01)and the p-mTOR/mTOR ratio(P<0.05),but a significant increase in the expression of the muscle ring finger 1(MuRF-1)and the muscle atrophy F-box(MAFbx/Atrog-in-1)(P<0.01 and P<0.05,respectively).(2)Compared with group M,group EM showed significant-ly greater heart weight(P<0.05);increased left ventricular posterior wall thickness at end-diastole(LVPWd),LVEF,FS and SV(P<0.05),as well as the larger cardiomyocyte CSA and total mTOR,p-mTOR and the p-mTOR/mTOR ratio(P<0.05),but reduced MuRF-1 and Atrogin-1 expression(P<0.05).Conclusion Four weeks of aerobic exercise preconditioning ameliorated myocardial atrophy and improved systolic cardiac function in mice bearing subcutaneously transplanted CT26 tumors.Such beneficial effects may be associated with exercise-induced down regulation of the protein degradation mediators MuRF-1 and Atrogin-1 and up regulation of total mTOR and p-mTOR.

Objective To investigate the effects of aerobic exercise and different exercise habits on skeletal muscle function and the possible molecular mechanisms in colorectal cancer-loaded mice.Methods Thirty-five 5-week-old BABL/c male mice were acclimatized to feeding for 1 week and then divided randomly into the following groups:control(D),tumor(M),exercise preconditioning(QAM),lifetime exercise(AM),and exercise(HAM)groups(n=7 mice per group).Mice in the QAM and AM groups underwent aerobic exercise regimen 1 from weeks 2～6.At week 7,mice in the experimental groups received 0.2 mL of CT26 colon cancer cell suspension subcutaneously in the dorsal aspect of the left hind limb,while control mice received 0.2 mL of saline at the corresponding site.Mice in the AM and HAM groups were subjected to aerobic exercise regimen 2 for weeks 7～9.The general status and skeletal muscle mass and function were monitored in all mice throughout the experiments.After completion of the experiment,samples were collected and the cross-sectional area of gastrocnemius muscle fibers(CSA)was measured by hematoxylin and eosin staining and expression levels of proteins related to synthesis and catabolism of the gastrocnemius muscle were analyzed by Western Blot.Results(1)The weight ratio of the gastrocnemius muscle was significantly lower in mice in the M,QAM,and HAM groups compared with group D,and was significantly higher in AM mice compared with M,QAM,and HAM mice.(2)Grip strength,endurance,skeletal muscle circumference,and CSA were significantly lower in group D mice compared with the other groups,and was most enhanced in group HAM.Endurance and CSA were consistently enhanced in groups QAM,AM,and HAM.(3)Muscle RING-finger protein-1(MuRF1)expression levels were significantly lower in groups M,QAM,AM,and HAM than in group D,significantly lower in groups AM and HAM than in group M,and significantly lower in group HAM than in group QAM.(4)Fibronectin type Ⅲ domain-containing protein 5(FNDC5)expression levels were significantly lower in group M than in groups D and QAM.(5)Peroxisome proliferator-activated receptor gamma coactivator 1-alpha expression levels were significantly lower in the QAM and HAM groups compared with group M.(6)Expression levels of phospho(p)-AMP-activated protein kinase(AMPK)/AMPK and p-AMPK were significantly higher in group QAM than in groups D and M,p-AMPK expression significantly lower in groups AM and HAM was than in group QAM,and AMPK expression was significantly lower in groups QAM,AM,and HAM than in group D.Conclusions Exercise preconditioning and continuous aerobic exercise can improve skeletal muscle mass and function in CT26 colon cancer-loaded mice by activating AMPK phosphorylation to stimulate skeletal muscle secretion of FNDC5,thereby regulating the expression of MuRF1 protein.

Objective To investigate the effects of aerobic exercise and different exercise habits on skeletal muscle function and the possible molecular mechanisms in colorectal cancer-loaded mice.Methods Thirty-five 5-week-old BABL/c male mice were acclimatized to feeding for 1 week and then divided randomly into the following groups:control(D),tumor(M),exercise preconditioning(QAM),lifetime exercise(AM),and exercise(HAM)groups(n=7 mice per group).Mice in the QAM and AM groups underwent aerobic exercise regimen 1 from weeks 2～6.At week 7,mice in the experimental groups received 0.2 mL of CT26 colon cancer cell suspension subcutaneously in the dorsal aspect of the left hind limb,while control mice received 0.2 mL of saline at the corresponding site.Mice in the AM and HAM groups were subjected to aerobic exercise regimen 2 for weeks 7～9.The general status and skeletal muscle mass and function were monitored in all mice throughout the experiments.After completion of the experiment,samples were collected and the cross-sectional area of gastrocnemius muscle fibers(CSA)was measured by hematoxylin and eosin staining and expression levels of proteins related to synthesis and catabolism of the gastrocnemius muscle were analyzed by Western Blot.Results(1)The weight ratio of the gastrocnemius muscle was significantly lower in mice in the M,QAM,and HAM groups compared with group D,and was significantly higher in AM mice compared with M,QAM,and HAM mice.(2)Grip strength,endurance,skeletal muscle circumference,and CSA were significantly lower in group D mice compared with the other groups,and was most enhanced in group HAM.Endurance and CSA were consistently enhanced in groups QAM,AM,and HAM.(3)Muscle RING-finger protein-1(MuRF1)expression levels were significantly lower in groups M,QAM,AM,and HAM than in group D,significantly lower in groups AM and HAM than in group M,and significantly lower in group HAM than in group QAM.(4)Fibronectin type Ⅲ domain-containing protein 5(FNDC5)expression levels were significantly lower in group M than in groups D and QAM.(5)Peroxisome proliferator-activated receptor gamma coactivator 1-alpha expression levels were significantly lower in the QAM and HAM groups compared with group M.(6)Expression levels of phospho(p)-AMP-activated protein kinase(AMPK)/AMPK and p-AMPK were significantly higher in group QAM than in groups D and M,p-AMPK expression significantly lower in groups AM and HAM was than in group QAM,and AMPK expression was significantly lower in groups QAM,AM,and HAM than in group D.Conclusions Exercise preconditioning and continuous aerobic exercise can improve skeletal muscle mass and function in CT26 colon cancer-loaded mice by activating AMPK phosphorylation to stimulate skeletal muscle secretion of FNDC5,thereby regulating the expression of MuRF1 protein.

Objective To investigate the effect of aerobic exercise preconditioning on cardiac function in mice bearing subcutaneous transplantable tumors and explore the potential molecular mechanisms.Methods Twenty-four 6-week-old male BALB/c mice were selected.After an acclimation period,they were randomly assigned to a control group(C),a tumor group(M)and an exercise-preconditioning plus tumor group(EM),each of eight.The EM group underwent a 4-week aerobic exercise interven-tion.Meanwhile,the C group received 0.2 ml of physiological saline injected subcutaneously on the dorsum of the proximal left hind limb,while the M and EM groups were inoculated at the same site with 0.2 ml of a CT26.WT colon carcinoma cell suspension.Three weeks after inoculation,cardiac function was assessed by transthoracic echocardiography.Hearts were then harvested for hematoxylin-eo-sin staining to evaluate cardiomyocyte cross-sectional area(CSA),while Western blot was performed to determine the expression of proteins related to myocardial protein synthesis and degradation.Results(1)Compared with group C,group M exhibited significantly lower body weight and heart weight(P<0.05),and reduced left ventricular ejection fraction(LVEF),fractional shortening(FS)and stroke vol-ume(SV)(P<0.05),as well as cardiomyocyte CSA(P<0.01)and total mTOR(P<0.01),phosphory-lated mTOR(p-mTOR)(P<0.01)and the p-mTOR/mTOR ratio(P<0.05),but a significant increase in the expression of the muscle ring finger 1(MuRF-1)and the muscle atrophy F-box(MAFbx/Atrog-in-1)(P<0.01 and P<0.05,respectively).(2)Compared with group M,group EM showed significant-ly greater heart weight(P<0.05);increased left ventricular posterior wall thickness at end-diastole(LVPWd),LVEF,FS and SV(P<0.05),as well as the larger cardiomyocyte CSA and total mTOR,p-mTOR and the p-mTOR/mTOR ratio(P<0.05),but reduced MuRF-1 and Atrogin-1 expression(P<0.05).Conclusion Four weeks of aerobic exercise preconditioning ameliorated myocardial atrophy and improved systolic cardiac function in mice bearing subcutaneously transplanted CT26 tumors.Such beneficial effects may be associated with exercise-induced down regulation of the protein degradation mediators MuRF-1 and Atrogin-1 and up regulation of total mTOR and p-mTOR.

Organ preservation fluid could mitigate cold ischemia injury and maintain normal function of the grafts. At present, how to reduce a series of injury caused by cold ischemia of donor liver and improve the preservation quality of grafts are the hot and challenging spots in this field. Currently, preservation fluid in clinical practice has not achieved ideal preservation effect, especially for the protection of marginal donor organs. In the context of severe donor shortage, the key solution is still to explore the optimal preservation protocol for donor liver to prevent grafts from cold ischemia injury. In this article, the mechanism of donor liver injury during cold ischemia, the classification and evolution of donor liver preservation fluid were summarized, the development direction and challenges of donor liver preservation fluid were discussed, aiming to provide novel ideas and references for the research and development of donor liver preservation fluid.

ObjectiveTo analyze the failure of antiretroviral therapy (ART) and drug resistance characteristics among the newly reported HIV-infected patients in Taizhou City from 2020 to 2022. MethodsBlood samples, sociodemographic characteristics and ART information of the newly reported HIV-infected patients who received ART for ≥6 months in Taizhou City from 2020 to 2022 were collected for the detection of recent infections and HIV-1 genotypic drug resistance. Multivariate logistic regression analysis was used to analyze the influencing factors of treatment failure. The gene sequences of cases with failed ART were submitted to the HIV drug resistance database of Stanford University to determine the drug resistance mutation sites and drug resistance characteristics. ResultsAmong the 1 023 newly reported HIV-infected patients receiving ART, the median age （P₂₅，P₇₅） was 47 (33, 58) years, 81.4% were male, 66.4% (679/1 023) were infected through heterosexual transmission, 74.7% had a WHO clinical stage Ⅰ/Ⅱ, 62.2% had a baseline CD4 count of >200 cell·μL^-1, 94.4% (966/1 023) received an immediate ART, and 78.7% were long-term infected. Among the 66 patients with treatment failure (6.5%), the likelihood of treatment failure was lower in those with homosexual transmission (OR=0.39, 95%CI: 0.17‒0.84) and without history of sexually transmitted disease (STD) (OR=0.45, 95%CI: 0.24‒0.92), but higher in those with a baseline CD4 count of ≤200 cell·μL^-1, delayed ART (OR=3.19, 95%CI: 1.24‒7.52), and primary drug resistance (OR=4.69, 95%CI: 1.68‒11.89). Among the 36 HIV-infected patients with virological failure, 27 sequences were successfully amplified, with a successful amplification rate of 75.0% (27/36). The total drug resistance rate was 55.6% (15/27), of which the drug resistance rates of nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs) and protease inhibitors (PIs) were 37.0% (10/27), 51.9% (14/27) and 3.7% (1/27), respectively. Among the NNRTIs, the degree of resistance to efavirenz and nevirapine was consistent, with a majority (51.9%) of highly drug-resistant. K103N and M184V were the most common mutation sites, but PIs mutations occured less frequently. A total of 8 genotypes of HIV-1 were detected, in which subtype CRF01_AE accounted for 37.0% (10/27), followed by CRF07_BC [14.8% (4/27)], CRF08_BC [14.8% (4/27)] and subtype C [14.8% (4/27)]. ConclusionDuring the period from 2020 to 2022, the newly reported HIV-infected individuals in Taizhou City were predominated by long-term infections. Immediate initiation of ART can reduce the risk of treatment failure in HIV-infected individuals. Virological treatment failures are primarily associated with resistance to NRTIs and NNRTIs. It is recommended to strengthen active detection and promptly initiate ART to minimize the occurrence of ART failure. Simultaneously, there is a need to intensify drug resistance detection targeted for those with treatment failure, so as to provide a scientific guidance for drug replacement.

Objective:To analyze the epidemiological characteristics of a family and workplace clustering of COVID-19， identify the source of infection and the transmission chain， and provide evidence for prevention and control of COVID-19 pandemic. Method:Field epidemiological method was used to conduct the investigation of confirmed cases and close contacts in this cluster. Data were analyzed with descriptive method. Real-time fluorescent quantitative PCR （RT-PCR） was used to detect the novel coronavirus nucleic acid in the collected respiratory tract samples. Results:A total of 18 epidemiological related cases were collected including 16 confirmed cases and 2 cases of asymptomatic infections. The involved places included 1 beauty clinic workplace and 3 families. Seven cases were males and 11 cases were females， with the minimum， maximum and median age of 3， 65 and 32 years old， respectively. Among them， the employees attack rate was 9.80% （10/102）， the family attack rate was 7.70% （5/78）， and the customer attack rate was 0.58% （1/173）. Positive nucleic acid test result in the respiratory tract sample of asymptomatic infection lasted for more than 2 months. Conclusions:The cause of this clustered COVID-19 epidemic is that the workplace environment is relatively closed with clustering crowds， and the source of imported infection is not discovered in time， which lead to a point-source outbreak and spread through family close contacts and clustering.