Objective To analyze the trend of changes in the ranges of body mass index(BMI)among students at a university in Tianjin from 2021 to 2024,and to propose intervention strategies based on the key influencing factors.Methods A total of 1 000 first-year students enrolled in 2021 at a university in Tianjin were randomly selected,and their physical fitness test data over the 4 years of undergraduate study were collected.Differences in physical fitness test results were compared among students with varying BMI ranges.Linear regression analysis was used to identify the key factors affecting changes in BMI ranges in the students.Results The proportion of underweight students remained relatively stable,decreasing slightly from 2.5%in the first year to 2.0%in the senior year.The proportion of students with normal weight showed a fluctuating downward trend,from 71.5%at college enrollment to 69.0%by the fourth year.In contrast,the proportion of overweight/obese students showed a fluctuating upward trend.In physical fitness tests for the first year,overweight/obese students showed the best performance in the standing long jump test([2.15±0.42]m,P=0.08),normal-weight students showed the best performance in the sit-and-reach test([20.1±7.5]cm,P=0.03),and underweight students performed best in the sit-up test(1 min[48.7±19.5]repeats,P=0.02).Simple linear regression analysis revealed that students who changed from being underweight to having normal weight by the senior year showed associations with sit-up performance(β=0.03,95%CI,0.018 to 0.041)and 1 000 m run(β=0.73,95%CI,0.601 to 0.877).Students who transitioned from having normal weight to being overweight/obese were showed negative associations with their performance in 800 m run(β=-0.08,95%CI,-0.102 to-0.047)and 1 000 m run(β=-16.9,95%CI,-19.110 to-13.826).Students who changed from being overweight/obese to having normal weight showed associations with their performance in standing long jump(β=-0.41,95%CI,-0.631 to-0.227)and 1 000 m run(β=-0.15,95%CI,-0.215 to-0.073).Conclusion Male students of different BMI ranges should focus on improving their 1 000 m run performance,and overweight/obese male students should emphasize standing long jump training as well.Underweight female students should strengthen sit-up training,normal-weight female students should focus on 800 m run training,and overweight/obese females students should strengthen standing long jump training.

BACKGROUND:Sarcopenic obesity is a syndrome characterized by the loss of muscle mass and an increase in body fat,which increases the risk of metabolic diseases and physical disabilities in the elderly.Blood flow restriction training involves applying pressure to a body part during exercise to reduce blood flow,achieving the effects of high-intensity training with low-intensity exercise,making it suitable for the elderly and those with limited mobility.OBJECTIVE:To review and discuss the biological mechanisms,effectiveness,and limitations of blood flow restriction training in addressing sarcopenic obesity in the elderly,and to provide exercise prescription recommendations based on current evidence.METHODS:Literature published up to September 2024 was retrieved from major databases.English and Chinese search terms included"blood flow restriction training,KAATSU,elderly,sarcopenia,sarcopenic obesity,muscle,fat."A total of 66 articles were selected,organized,and analyzed.RESULTS AND CONCLUSION:This study explored the biological mechanisms of blood flow restriction training,including creating an ischemic-hypoxic environment,accumulating metabolites,activating potential signaling pathways,and promoting satellite cell proliferation.The effectiveness of blood flow restriction training in improving muscle strength,mass,and reducing body fat was evaluated,and its potential advantages and risks in the elderly population were discussed.It is recommended that elderly patients with sarcopenic obesity undergo blood flow restriction training combined with 20%-40%1 RM resistance training for three to four times per week.Starting from the first week,there are three sets of training with 30,15,and 15 repetitions respectively.From the second week,there are four sets with 30,15,15,and 15 repetitions respectively.The rest interval between each set is 30-60 seconds.The cuffwidth is 3-5 cm.The pressure of each set increases incrementally by 40%,60%,and 80%of the arterial occlusion pressure.The airbag pressure ranges from 80 to 240 mmHg.Future research is needed to further verify the long-term effects of blood flow restriction training,optimize the training protocol,and explore its application possibilities in different disease contexts.

BACKGROUND:Sarcopenic obesity is a syndrome characterized by the loss of muscle mass and an increase in body fat,which increases the risk of metabolic diseases and physical disabilities in the elderly.Blood flow restriction training involves applying pressure to a body part during exercise to reduce blood flow,achieving the effects of high-intensity training with low-intensity exercise,making it suitable for the elderly and those with limited mobility.OBJECTIVE:To review and discuss the biological mechanisms,effectiveness,and limitations of blood flow restriction training in addressing sarcopenic obesity in the elderly,and to provide exercise prescription recommendations based on current evidence.METHODS:Literature published up to September 2024 was retrieved from major databases.English and Chinese search terms included"blood flow restriction training,KAATSU,elderly,sarcopenia,sarcopenic obesity,muscle,fat."A total of 66 articles were selected,organized,and analyzed.RESULTS AND CONCLUSION:This study explored the biological mechanisms of blood flow restriction training,including creating an ischemic-hypoxic environment,accumulating metabolites,activating potential signaling pathways,and promoting satellite cell proliferation.The effectiveness of blood flow restriction training in improving muscle strength,mass,and reducing body fat was evaluated,and its potential advantages and risks in the elderly population were discussed.It is recommended that elderly patients with sarcopenic obesity undergo blood flow restriction training combined with 20%-40%1 RM resistance training for three to four times per week.Starting from the first week,there are three sets of training with 30,15,and 15 repetitions respectively.From the second week,there are four sets with 30,15,15,and 15 repetitions respectively.The rest interval between each set is 30-60 seconds.The cuffwidth is 3-5 cm.The pressure of each set increases incrementally by 40%,60%,and 80%of the arterial occlusion pressure.The airbag pressure ranges from 80 to 240 mmHg.Future research is needed to further verify the long-term effects of blood flow restriction training,optimize the training protocol,and explore its application possibilities in different disease contexts.

Objective:To investigate the clinicopathological features and molecular characteristics of β-catenin-deficient colorectal cancer.Methods:The clinical, pathological and molecular features of 11 colorectal cancers with β-catenin protein loss diagnosed at the 960th Hospital of People′s Liberation Army of China, from January 2012 to November 2022 were analyzed.Results:Among the 11 patients, 3 were males and 8 were females. Their age ranged from 43 to 74 years, with the median age of 59 years. Six were in the left colon and 5 were in the right colon. One of the 11 cases had lymph node metastasis, 10 cases were well and moderately differentiated adenocarcinoma, and 1 was mucinous adenocarcinoma. Eight cases were of TNM stage T4, 2 of T1 stage and 1 of Tis stage. β-catenin protein was not detected using immunohistochemistry. Sanger sequencing revealed the presence of fragment-deletion mutation in exon 3 of CTNNB1 gene, resulting in loss of β-catenin protein expression.Conclusion:β-catenin deficiency is present in a small number of colorectal cancers and may be associated with exon 3 mutations of CTNNB1 gene.

Objective: To analyze the association of 24 h activity behaviors and physical health of primary school students, so as to provide a reference for promoting the physical health of children and adolescents. Methods: From May to June, 2023, by stratified random sampling method, 583 primary school students aged 7-12 were selected from Tianjin for physical health examination. ActiGraph GT3X+ was used to measure their 24 h activity behaviors for 7 d, and their mental health and 24 h activity behaviors were analyzed by gender and grade. LASSO regression was applied for assessing the impact of 24 h activity on their health. Results: The compliance rate of seated forward bending (93.12%) were higher in boys than girls (91.86%), and the differences were statistically significant ( χ 2=4.53, P <0.05). Sleep time ( β =0.06), light intensity physical activity (LPA) time ( β =0.11), and moderate to vigorous physical activity (MVPA) time ( β =0.14) were positively correlated with physical fitness, whereas sedentary behavior (SB) time ( β =-0.08) were negatively correlated with physical fitness, and MVPA time had a positive effect on physical health of children and adolescents, followed by LPA time; while sleep time also had a positive effect , and SB time had a negative effect ( P <0.05). Conclusions Primary school students are generally faced with low physical activity level and high SB time, and MVPA and LPA have a significant impact on physical health. Therefore, it is crucial to develop personalized and differentiated physical activity promotion policies and interventions for primary school students with different classmates and gender.

BACKGROUND:Sarcopenia refers to age-related progressive,systemic muscle mass reduction and/or muscle strength decline or muscle physiological function decline,which is related to the occurrence of a variety of adverse outcomes in older adults.Exercise is considered to be one of the main strategies for combating sarcopenia in older adults,but there is a lack of specific intervention methods of different exercise patterns to intervene in sarcopenia. OBJECTIVE:To elaborate the main influencing factors of sarcopenia and the research progress of different exercise methods to improve sarcopenia in older adults,providing reference and basis for combating sarcopenia in older adults. METHODS:Web of Science,PubMed,CNKI,VIP,WanFang databases were retrieved for relevant literature published from January 2000 to October 2023 using the keywords of"sarcopenia,sport,exercise intervention,resistant training,aerobic exercise,whole body vibration training,mixed training,physical performance,muscle strength,muscle mass"in Chinese and English,respectively.A total of 126 articles were included for review. RESULTS AND CONCLUSION:Resistance exercise is still the most effective way to prevent and treat senile sarcopenia,and the effect of high-intensity resistance exercise is more significant.However,in practical application,we should pay attention to the gradual increase of training load intensity.Aerobic exercise combined with resistance exercise is more effective to improve muscle mass and function in the elderly than a single exercise mode.It is suggested that older adults can carry out the transition of low-intensity aerobic exercise in the early stage and increase resistance exercise individually in the late stage.Whole body vibration training is a new treatment method for the prevention and treatment of senile sarcopenia,but particular attention should be paid to the effects of frequency,amplitude,and duration on patients during practical application.Multicomponent exercise combines different exercise modes,which can give full play to their respective advantages,so as to personalize exercise interventions.

Objective: An isochronous substitution model was established to explore the association and substitution effect between college students 24 hour activity behavior and physical health, so as to provide specific activity behavior suggestions for college students to improve their physical health. Methods: A stratified random cluster sampling method was used to conduct physical fitness tests and 24 hour activity behavior surveys among 2 794 college students in 12 colleges and universities in Tianjin.Time spent on sedentary behavior(SB), light intensity physical activity(LPA), moderate to vigorous physical activity(MVPA) and sleep(SLP) time. The isochronous method of components was used to explore the relationship between 24 h activity behavior and physical health. Results: Except for 50 m running, MVPA was negatively correlated with BMI Z ( β =-0.62, P <0.05), but positively correlated with other physical fitness indexes ( β =0.34~274.23, P <0.05). LPA was not associated with lung capacity, sitting forward flexion and 50 m running, and negatively correlated with other physical fitness indexes ( β =-14.30- -0.19, P <0.05). SB was negatively correlated with most physical fitness indexes ( β =-11.57- -0.33, P <0.05), but positively correlated with BMI Z ( β =0.45, P < 0.05 ). In addition to lung capacity, SLP was positively correlated with BMI Z , total physical fitness score,1 minute sit-ups, pull ups, 800/1 000 m running, sitting forward flexion, and 50 m running ( β =0.27-11.21, P <0.05), but negatively correlated with long jump ( β =-0.10, P <0.05）. Isochronous substitution showed that the adverse effects of 30 min/d SB and LPA substitution of MVPA were much greater than the beneficial effects of MVPA substitution for corresponding behaviors (total physical score: SB, -0.58 vs 0.47 points; LPA, -0.50 vs 0.38 points). Conclusion MVPA and SLP have been found to have a positive effect on physical fitness among college students. Therefore, in the process of improving the physical health of college students, ensuring adequate sleep, improving MVPA and reducing SB as much as possible may be one of the effective methods.

OBJECTIVETo observe the pathological changes in rabbits with spinal cord injury induced by decompression sickness (DCS), and to investigate the role of tumor necrosis factor-alpha (TNF-α) in spinal cord injury induced by DCS.

METHODSRabbits were randomly divided into normal control group, DCS group, and safe decompression group. The rabbit model of DCS was established. Light microscopy, real-time PCR, and immunohistochemical method were used to observe the pathomorphological changes in the thoracolumbar spinal cord and the mRNA and protein expression of TNF-α, respectively. The terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) was used to observe the apoptosis in the spinal cord.

RESULTSIn the DCS group, cavities formed in the white matter of spinal cord and gliosis occurred around necrotic areas. Moreover, the mRNA and protein expression of TNF-α was significantly higher in the DCS group than in the normal control group and the safe decompression group (P<0.01). The results of TUNEL showed that the number of positive apoptotic cells was significantly larger in the DCS group than in the normal control group and the safe decompression group (P<0.05).

CONCLUSIONApoptosis plays an important role in spinal cord injury induced by DCS. In the early stage of DCS, the massive release of TNF-α initiates apoptosis and contributes to the pathological changes in spinal cord injury induced by DCS.

Animals ; Apoptosis ; Decompression Sickness ; metabolism ; pathology ; Disease Models, Animal ; In Situ Nick-End Labeling ; RNA, Messenger ; Rabbits ; Spinal Cord ; pathology ; Spinal Cord Injuries ; metabolism ; pathology ; Tumor Necrosis Factor-alpha ; metabolism

Objective To investigate the effects of astrocyte and microglia on spinal cord injury of the rabbits in decompression sickness (DCS).Methods Twenty-one healthy adult male New Zealand rabbits were averagely divided into 3 groups according to random number table:control group,safety relief group and DCS group.Experimental animals were placed in the pressure cabin.Safety relief group model referred to the Chinese Navy diving decompression tables when decompression applied.In DCS group,the pressure equably was increased to 0.8 MPa (absolute pressure) within 5 min by compressed air,maintained for 60 min and then equably decompressed to normal pressure within 5 min.The change of pathology morphology in the spinal cord of thoracolumbar vertebra was observed by light microscope.The expression of tumor necrosis factor-a (TNF-a) and Glial Fibrillary Acidic Protein (GFAP) mRNA were measured by real-time polymerase chain reaction (real-time PCR) and the expression of TNF-α,GFAP,ionized calcium binding adapter molecule 1 (IBA1) protein was measured by immunohistochemistry method.Results There were some cavity formations on white matter of spinal cord in DCS group.The relative expression of TNF-α mRNA was higher in DCS (6.28±1.73) than that in control group (1.00±0.14) and in safety relief group (1.34±0.42) (P＜0.01).The relative expression of GFAP mRNA was higher in DCS (7.39±2.04) than in that control group (1.02±0.26) and in safety relief group (1.63±0.90) (P＜ 0.01).The expression of TNF-α protein was significantly higher in DCS group (24.14± 2.61) than that in control group (6.71±1.25) and in safety relief group (8.28 ± 1.11) (P＜0.01).The expression of GFAP protein was also significantly higher in DCS (18.20±4.38) than that in control group (4.30±2.70) and in safety relief group (6.20±2.92) (P＜0.01).The expression of IBA1 protein was also significantly higher in DCS (21.53±1.37) than that in control group (5.94±0.36) and in safety relief group (6.69 ± 0.81) (P＜0.01).Conclusions The astrocyte and microglia may play a key role in pathophysiology of spinal cord injury.They are activated in the early stage of DCS and accompanied with massive release of TNF-α,which causes excessive inflammation reaction and induces the spinal cord injury finally.

Objective To investigate the effects of astrocyte and microglia on spinal cord injury of the rabbits in decompression sickness (DCS).Methods Twenty-one healthy adult male New Zealand rabbits were averagely divided into 3 groups according to random number table:control group,safety relief group and DCS group.Experimental animals were placed in the pressure cabin.Safety relief group model referred to the Chinese Navy diving decompression tables when decompression applied.In DCS group,the pressure equably was increased to 0.8 MPa (absolute pressure) within 5 min by compressed air,maintained for 60 min and then equably decompressed to normal pressure within 5 min.The change of pathology morphology in the spinal cord of thoracolumbar vertebra was observed by light microscope.The expression of tumor necrosis factor-a (TNF-a) and Glial Fibrillary Acidic Protein (GFAP) mRNA were measured by real-time polymerase chain reaction (real-time PCR) and the expression of TNF-α,GFAP,ionized calcium binding adapter molecule 1 (IBA1) protein was measured by immunohistochemistry method.Results There were some cavity formations on white matter of spinal cord in DCS group.The relative expression of TNF-α mRNA was higher in DCS (6.28±1.73) than that in control group (1.00±0.14) and in safety relief group (1.34±0.42) (P＜0.01).The relative expression of GFAP mRNA was higher in DCS (7.39±2.04) than in that control group (1.02±0.26) and in safety relief group (1.63±0.90) (P＜ 0.01).The expression of TNF-α protein was significantly higher in DCS group (24.14± 2.61) than that in control group (6.71±1.25) and in safety relief group (8.28 ± 1.11) (P＜0.01).The expression of GFAP protein was also significantly higher in DCS (18.20±4.38) than that in control group (4.30±2.70) and in safety relief group (6.20±2.92) (P＜0.01).The expression of IBA1 protein was also significantly higher in DCS (21.53±1.37) than that in control group (5.94±0.36) and in safety relief group (6.69 ± 0.81) (P＜0.01).Conclusions The astrocyte and microglia may play a key role in pathophysiology of spinal cord injury.They are activated in the early stage of DCS and accompanied with massive release of TNF-α,which causes excessive inflammation reaction and induces the spinal cord injury finally.