Objective:To explore the prospective association between physical activity level and mor-tality risk in Chinese adults with chronic obstructive pulmonary disease(COPD).Methods:Based on the China Kadoorie Biobank(CKB)who had COPD at the baseline survey,this study employed the Cox proportional hazards regression model to estimate the prospective associations between the overall physical activity,different intensities(low-level,moderate-to-vigorous-level),and types(occupational,non-occupational)of physical activity level and the risks of all-cause and cause-specific mortality,such as vascular diseases,cancer,and respiratory diseases.Based on the quintiles of physical activity level,par-ticipants were divided into five groups(Q1-Q5),with the lowest quintile group(Q1)as the reference group.Hazard ratio(HR)and 95％confidence interval(95％CI)were calculated for the remaining.In our study,we also performed sensitivity and subgroup analyses,including age,gender,self-rated health status,severity of COPD,etc.Results:Among 33 588 COPD patients at the baseline survey,8 314(22.2％)deaths were documented during an average follow-up of(11.1±3.1)years.Negative linear associations between the overall physical activity level and mortality risk from all-cause,vascular,and respiratory diseases were observed(P trend for linear correlation being＜0.001,0.002,＜0.001).Compared with the lowest quintile group of total physical activity(Q1),the hazard ratios(HR)and 95％confidence intervals(CI)for all-cause mortality,vascular disease mortality,and respiratory disease mortality in the highest quintile group(Q5)were 0.77(0.70,0.85),0.77(0.65,0.91),and 0.58(0.48,0.71),respectively.The low-level and moderate-to-vigorous-level physical activity were nega-tively associated with all-cause mortality in the COPD patients(P trend for linear correlation:0.002,＜0.001,respectively).Compared with the lowest quintile group of low-intensity and moderate-to-vigorous intensity physical activity(Q1),the HRs(95％CI)for all-cause mortality in the highest quintile group(Q5)were 0.89(0.82,0.97)and 0.79(0.72,0.87),respectively.The occupational and non-occupational physical activity were also found to have a linear inverse association with all-cause mortality risk among the COPD patients(P trend＜0.001 and 0.015,respectively).Compared with the lowest quintile group of occupational and non-occupational physical activity(Q1),the HR(95％CI)for all-cause mortality in the highest quintile group(Q5)were 0.69(0.61,0.78)and 0.91(0.84,0.98),respectively.The associations between overall physical activity and all-cause mortality risk were stronger for patients aged 60 and above,female,and who reported poor health status(P for interaction:0.028,0.012,0.010).The protective effect of total physical activity was also applicable to the COPD patients of varying severity.Conclusion:Physical activity could reduce the mortality risk in a dose-response relationship among COPD patients,regardless of its intensity and type,especially among indi-viduals aged 60 and above,females,and those with poor self-report health status.

Objective To investigate the relationship between platelet distribution width(PDW)and coronary artery calcification(CAC)in overweight and obese populations.Methods Clinical and chest CT data of 10 838 subjects with overweight or obesity(body mass index[BMI]≥24 kg/m2)were retrospectively analyzed.The subjects were divided into CAC group(n=4 237)and non-CAC group(n=6 601)based on CAC scores obtained from chest CT.The relationship between PDW and CAC in overweight and obese populations was analyzed after controlling confounding variables.A threshold effect analysis was conducted using a two-stage logistic model to find the non-linear inflection point.Subgroup analyses and interaction tests were conducted to validate the stability of the relationship between PDW and CAC.Results Non-linear relationship was observed between PDW and CAC risk in overweight and obese populations.The risk of CAC decreased with the increase of PDW which ≤17.80％(OR=0.82),but increased with the increase of PDW(OR=1.04)which＞17.80％.Subgroup analysis showed that the relationship between PDW and CAC remained stable in subgroups of different genders,BMI(＜28 kg/m2,≥28 kg/m2)and hypertension(all P＞0.05).Compared with aged＜40 years or ≥60 years subgroups,under the same PDW,aged≥40 and＜60 years subgroups had higher risk of CAC(interaction P=0.015).Conclusion Nonlinear relationship existed between PDW and CAC in overweight and obese populations.Both excessively high and low PDW were risk factors of CAC.

BACKGROUND:Acellular cartilage extracellular matrix is effective in the treatment of osteoarthritis,but its efficacy is limited when applied alone.Oxymatrine alleviates interleukin-1β-induced chondrocyte apoptosis and extracellular matrix degradation.OBJECTIVE:To observe the effect of different doses of oxymatrine combined with acellular cartilage extracellular matrix injection in knee cavity on osteoarthritis in rats.METHODS:The femoral cartilage of SD rats was obtained.The acellular cartilage extracellular matrix was prepared by physical,chemical and enzyme methods.Fifty SD rats were selected and divided into sham operation group,osteoarthritis group,simple material group,low-dose drug group,and high-dose drug group by random number table method,with 10 rats in each group.The latter four groups were treated with modified Hulth method to establish the rat model of osteoarthritis.After successful modeling,acellular cartilage extracellular matrix homogenate was injected into the knee cavity of rats in the simple material group.Acellular cartilage extracellular matrix homogenate containing 50,100 μg oxymatrine was injected into the knee cavity of rats in the low-dose drug group and the high-dose drug group,respectively.Samples were taken 4 weeks after injection for relevant detection.RESULTS AND CONCLUSION:(1) Compared with the sham operation group,the concentrations of interleukin 1β,tumor necrosis factor ɑ,and malondialdehyde in the joint effusion were increased (P<0.05),and the concentration of superoxide dismutase in the joint effusion was decreased (P<0.05) in the osteoarthritis group.Compared with osteoarthritis group,the levels of interleukin 1β,tumor necrosis factor ɑ,and malondialdehyde in joint effusion were decreased (P<0.05),while the level of superoxide dismutase was increased (P<0.05) in the low-dose drug group and high-dose drug group,and the changes were more significant in high-dose drug group.(2) TUNEL staining showed that compared with sham operation group,apoptotic chondrocytes increased in osteoarthritis group.Compared with the osteoarthritis group,the apoptotic chondrocytes decreased in the simple material group,the low-dose drug group,and the high-dose drug group,and the decrease was more significant in the high-dose drug group.(3) Hematoxylin-eosin staining and immunohistochemical staining showed that the knee cartilage was seriously degraded,the expression of type Ⅱ collagen was decreased (P<0.05),and the expression of matrix metalloproteinase-9 was increased (P<0.05) in the osteoarthritis group.Compared with the osteoarthritis group,the knee cartilage degeneration of rats in the simple material group,the low-dose drug group,and the high-dose drug group was significantly improved;the expression of type Ⅱ collagen was increased (P<0.05) and the expression of matrix metalloproteinase 9 was decreased (P<0.05),and the improvement was most significant in the high-dose drug group.(4) Western blot assay showed that compared with sham operation group,the expression of Nrf2,HO-1,and Bcl-2 protein in cartilage tissue decreased (P<0.05);expression levels of Cleaved-caspase-3,Cleaved-caspase-9,and Bax were increased (P<0.05) in the osteoarthritis group.Compared with the osteoarthritis group,the protein expression levels of Nrf2,HO-1,and Bcl-2 were increased (P<0.05),and the protein expressions of Cleaved-caspase-3,Cleaved-caspase-9,and Bax were decreased (P<0.05) in the low-dose and high-dose drug groups.The improvement was more significant in the high-dose drug group.(5) In conclusion,intracavicular injection of acellular cartilage extracellular matrix and oxymatrine can promote the synthesis of extracellular matrix,inhibit inflammation and oxidative stress,and suppress chondrocyte apoptosis,and play a therapeutic role in osteoarthritis,which may be related to the activation of Nrf2/HO-1 pathway.

Objective:To describe the prevalence of preserved ratio impaired spirometry (PRISm) in participants from the China Kadoorie Biobank (CKB) and explore the influencing factors.Methods:The CKB project conducted the baseline survey, the first and the second resurvey in 2004-2008, 2008, and 2013-2014, respectively. Based on the lung function tests, the participants were categorized into three groups: regular, PRISm, and airflow obstruction. The prevalence of PRISm was reported by gender, age, and region at the baseline survey. The secular trend in the prevalence of PRISm was described during the three surveys. Finally, we used the multiple logistic regression model to examine the factors related to PRISm in the baseline survey.Results:After standardization for gender, age, and region according to the sixth national census data in 2010, the overall prevalence of PRISm and airflow obstruction among the 434 760 participants at baseline was 24.8% and 6.1%, respectively. The prevalence of PRISm was higher in rural (25.4%) than that in urban areas (24.3%). Of the 10 study regions, Gansu had the highest prevalence of PRISm (56.0%), while Henan had the lowest (15.4%). After standardization for gender, age, and region according to the baseline population, the prevalence of PRISm decreased from 24.9% at baseline to 15.7% in the second resurvey, and the prevalence of airflow obstruction increased from 5.9% to 21.4%. Unmarried status, current smoking, using solid fuels for cooking, low body weight, being overweight, obesity, and central obesity were associated with an increased risk of PRISm. In contrast, higher education attainments, increased household income, and maintaining a specific degree of physical activity were associated with a reduced risk of PRISm.Conclusions:The prevalence of PRISm was high in adults aged 40 years and above in China, and it varied by sociodemographic and lifestyle factors.

Objective:To describe the prevalence of preserved ratio impaired spirometry (PRISm) in participants from the China Kadoorie Biobank (CKB) and explore the influencing factors.Methods:The CKB project conducted the baseline survey, the first and the second resurvey in 2004-2008, 2008, and 2013-2014, respectively. Based on the lung function tests, the participants were categorized into three groups: regular, PRISm, and airflow obstruction. The prevalence of PRISm was reported by gender, age, and region at the baseline survey. The secular trend in the prevalence of PRISm was described during the three surveys. Finally, we used the multiple logistic regression model to examine the factors related to PRISm in the baseline survey.Results:After standardization for gender, age, and region according to the sixth national census data in 2010, the overall prevalence of PRISm and airflow obstruction among the 434 760 participants at baseline was 24.8% and 6.1%, respectively. The prevalence of PRISm was higher in rural (25.4%) than that in urban areas (24.3%). Of the 10 study regions, Gansu had the highest prevalence of PRISm (56.0%), while Henan had the lowest (15.4%). After standardization for gender, age, and region according to the baseline population, the prevalence of PRISm decreased from 24.9% at baseline to 15.7% in the second resurvey, and the prevalence of airflow obstruction increased from 5.9% to 21.4%. Unmarried status, current smoking, using solid fuels for cooking, low body weight, being overweight, obesity, and central obesity were associated with an increased risk of PRISm. In contrast, higher education attainments, increased household income, and maintaining a specific degree of physical activity were associated with a reduced risk of PRISm.Conclusions:The prevalence of PRISm was high in adults aged 40 years and above in China, and it varied by sociodemographic and lifestyle factors.

BACKGROUND:Acellular cartilage extracellular matrix is effective in the treatment of osteoarthritis,but its efficacy is limited when applied alone.Oxymatrine alleviates interleukin-1β-induced chondrocyte apoptosis and extracellular matrix degradation.OBJECTIVE:To observe the effect of different doses of oxymatrine combined with acellular cartilage extracellular matrix injection in knee cavity on osteoarthritis in rats.METHODS:The femoral cartilage of SD rats was obtained.The acellular cartilage extracellular matrix was prepared by physical,chemical and enzyme methods.Fifty SD rats were selected and divided into sham operation group,osteoarthritis group,simple material group,low-dose drug group,and high-dose drug group by random number table method,with 10 rats in each group.The latter four groups were treated with modified Hulth method to establish the rat model of osteoarthritis.After successful modeling,acellular cartilage extracellular matrix homogenate was injected into the knee cavity of rats in the simple material group.Acellular cartilage extracellular matrix homogenate containing 50,100 μg oxymatrine was injected into the knee cavity of rats in the low-dose drug group and the high-dose drug group,respectively.Samples were taken 4 weeks after injection for relevant detection.RESULTS AND CONCLUSION:(1) Compared with the sham operation group,the concentrations of interleukin 1β,tumor necrosis factor ɑ,and malondialdehyde in the joint effusion were increased (P<0.05),and the concentration of superoxide dismutase in the joint effusion was decreased (P<0.05) in the osteoarthritis group.Compared with osteoarthritis group,the levels of interleukin 1β,tumor necrosis factor ɑ,and malondialdehyde in joint effusion were decreased (P<0.05),while the level of superoxide dismutase was increased (P<0.05) in the low-dose drug group and high-dose drug group,and the changes were more significant in high-dose drug group.(2) TUNEL staining showed that compared with sham operation group,apoptotic chondrocytes increased in osteoarthritis group.Compared with the osteoarthritis group,the apoptotic chondrocytes decreased in the simple material group,the low-dose drug group,and the high-dose drug group,and the decrease was more significant in the high-dose drug group.(3) Hematoxylin-eosin staining and immunohistochemical staining showed that the knee cartilage was seriously degraded,the expression of type Ⅱ collagen was decreased (P<0.05),and the expression of matrix metalloproteinase-9 was increased (P<0.05) in the osteoarthritis group.Compared with the osteoarthritis group,the knee cartilage degeneration of rats in the simple material group,the low-dose drug group,and the high-dose drug group was significantly improved;the expression of type Ⅱ collagen was increased (P<0.05) and the expression of matrix metalloproteinase 9 was decreased (P<0.05),and the improvement was most significant in the high-dose drug group.(4) Western blot assay showed that compared with sham operation group,the expression of Nrf2,HO-1,and Bcl-2 protein in cartilage tissue decreased (P<0.05);expression levels of Cleaved-caspase-3,Cleaved-caspase-9,and Bax were increased (P<0.05) in the osteoarthritis group.Compared with the osteoarthritis group,the protein expression levels of Nrf2,HO-1,and Bcl-2 were increased (P<0.05),and the protein expressions of Cleaved-caspase-3,Cleaved-caspase-9,and Bax were decreased (P<0.05) in the low-dose and high-dose drug groups.The improvement was more significant in the high-dose drug group.(5) In conclusion,intracavicular injection of acellular cartilage extracellular matrix and oxymatrine can promote the synthesis of extracellular matrix,inhibit inflammation and oxidative stress,and suppress chondrocyte apoptosis,and play a therapeutic role in osteoarthritis,which may be related to the activation of Nrf2/HO-1 pathway.

Objective:To explore the prospective association between physical activity level and mor-tality risk in Chinese adults with chronic obstructive pulmonary disease(COPD).Methods:Based on the China Kadoorie Biobank(CKB)who had COPD at the baseline survey,this study employed the Cox proportional hazards regression model to estimate the prospective associations between the overall physical activity,different intensities(low-level,moderate-to-vigorous-level),and types(occupational,non-occupational)of physical activity level and the risks of all-cause and cause-specific mortality,such as vascular diseases,cancer,and respiratory diseases.Based on the quintiles of physical activity level,par-ticipants were divided into five groups(Q1-Q5),with the lowest quintile group(Q1)as the reference group.Hazard ratio(HR)and 95％confidence interval(95％CI)were calculated for the remaining.In our study,we also performed sensitivity and subgroup analyses,including age,gender,self-rated health status,severity of COPD,etc.Results:Among 33 588 COPD patients at the baseline survey,8 314(22.2％)deaths were documented during an average follow-up of(11.1±3.1)years.Negative linear associations between the overall physical activity level and mortality risk from all-cause,vascular,and respiratory diseases were observed(P trend for linear correlation being＜0.001,0.002,＜0.001).Compared with the lowest quintile group of total physical activity(Q1),the hazard ratios(HR)and 95％confidence intervals(CI)for all-cause mortality,vascular disease mortality,and respiratory disease mortality in the highest quintile group(Q5)were 0.77(0.70,0.85),0.77(0.65,0.91),and 0.58(0.48,0.71),respectively.The low-level and moderate-to-vigorous-level physical activity were nega-tively associated with all-cause mortality in the COPD patients(P trend for linear correlation:0.002,＜0.001,respectively).Compared with the lowest quintile group of low-intensity and moderate-to-vigorous intensity physical activity(Q1),the HRs(95％CI)for all-cause mortality in the highest quintile group(Q5)were 0.89(0.82,0.97)and 0.79(0.72,0.87),respectively.The occupational and non-occupational physical activity were also found to have a linear inverse association with all-cause mortality risk among the COPD patients(P trend＜0.001 and 0.015,respectively).Compared with the lowest quintile group of occupational and non-occupational physical activity(Q1),the HR(95％CI)for all-cause mortality in the highest quintile group(Q5)were 0.69(0.61,0.78)and 0.91(0.84,0.98),respectively.The associations between overall physical activity and all-cause mortality risk were stronger for patients aged 60 and above,female,and who reported poor health status(P for interaction:0.028,0.012,0.010).The protective effect of total physical activity was also applicable to the COPD patients of varying severity.Conclusion:Physical activity could reduce the mortality risk in a dose-response relationship among COPD patients,regardless of its intensity and type,especially among indi-viduals aged 60 and above,females,and those with poor self-report health status.

Objective To investigate the relationship between platelet distribution width(PDW)and coronary artery calcification(CAC)in overweight and obese populations.Methods Clinical and chest CT data of 10 838 subjects with overweight or obesity(body mass index[BMI]≥24 kg/m2)were retrospectively analyzed.The subjects were divided into CAC group(n=4 237)and non-CAC group(n=6 601)based on CAC scores obtained from chest CT.The relationship between PDW and CAC in overweight and obese populations was analyzed after controlling confounding variables.A threshold effect analysis was conducted using a two-stage logistic model to find the non-linear inflection point.Subgroup analyses and interaction tests were conducted to validate the stability of the relationship between PDW and CAC.Results Non-linear relationship was observed between PDW and CAC risk in overweight and obese populations.The risk of CAC decreased with the increase of PDW which ≤17.80％(OR=0.82),but increased with the increase of PDW(OR=1.04)which＞17.80％.Subgroup analysis showed that the relationship between PDW and CAC remained stable in subgroups of different genders,BMI(＜28 kg/m2,≥28 kg/m2)and hypertension(all P＞0.05).Compared with aged＜40 years or ≥60 years subgroups,under the same PDW,aged≥40 and＜60 years subgroups had higher risk of CAC(interaction P=0.015).Conclusion Nonlinear relationship existed between PDW and CAC in overweight and obese populations.Both excessively high and low PDW were risk factors of CAC.

Objective:To analyze the correlation between body fat distribution measured by quantitative CT (QCT) and body mass index in adults receiving physical examination.Methods:It was a cross-sectional study. From January to December 2021, 3 205 adults undergoing physical examination who met the inclusion criteria and underwent chest CT and QCT examination in the health management discipline of Henan Provincial People′s Hospital were selected as the research objects. The general data were collected; and the subcutaneous fat area, visceral fat area, total abdominal fat area, liver fat content, abdominal obesity and fatty liver detection rate were measured by QCT. According to body mass index, the subjects were divided into normal group (18.5-<24.0 kg/m 2, 1 343 cases), overweight group (24.0-<28.0 kg/m 2, 1 427 cases) and obesity group (≥28.0 kg/m 2, 435 cases). One-way analysis of variance and χ2 test were used to compare the differences of QCT indexes among the three groups. Pearson and Spearman correlation analysis were used to evaluate the correlation between QCT indexes and body mass index. Receiver operating characteristic (ROC) curve was drawn to analyze the diagnostic effect of QCT on obesity and fatty liver. Results:Subcutaneous fat area, visceral fat area, total abdominal fat area, liver fat content, abdominal obesity and fatty liver detection rate in obese group were all significantly higher than those in overweight group and normal group [males, (147.60±46.44) vs (104.33±27.68), (73.46±22.65) cm 2; (297.46±54.70) vs (229.40±53.12), (159.57±49.68) cm 2; (445.06±70.24) vs (333.73±62.91), (233.02±61.87) cm 2; 11.30% (7.90%, 15.55%) vs 8.75% (6.50%, 11.70%), 6.60% (4.80%, 8.70%); 100.0% vs 96.0%, 64.0%; 92.9% vs 86.7%, 73.3%; females, (213.96±48.61) vs (155.85±35.31), (107.24±31.01) cm 2; (185.41±43.88) vs (142.48±41.75), (96.56±36.50) cm 2; (399.37±68.07) vs (298.33±56.86), (203.80±57.53) cm 2; 9.80% (6.90%, 13.30%) vs 7.30% (5.05%, 9.80%), 5.40%(3.50%, 7.20%); 96.4% vs 74.8%, 28.9%; 87.3% vs 75.6%, 56.5%], and were all positively correlated with body mass index (males, r/ rs=0.709, 0.738, 0.831, 0.402, 0.464, 0.225; females, r/ rs=0.798, 0.695, 0.841, 0.416, 0.605, 0.276) (all P<0.001). In both male and female subjects, the detection rates of obesity based on QCT were significantly higher than those based on body mass index (male, 86.9% vs 16.6%; female, 49.3% vs 8.9%), and the detection rates of fatty liver based on QCT were significantly higher than those based on ultrasound (male, 83.6% vs 57.1%; female, 65.2% vs 27.6%) (all P<0.001). ROC curve showed that when the visceral fat area of 142 cm 2 was used as the cut-off value for the diagnosis of obesity in male subjects, the sensitivity and specificity was 100% and 15.8%, respectively; and when the cut-off value of liver fat content 5.0% was used to diagnose fatty liver, the sensitivity and specificity was 88.9% and 25.1%, respectively. When the visceral fat area of 115 cm 2 was set as the cut-off value for the diagnosis of obesity in female subjects, the sensitivity and specificity was 96.4% and 55.3%, respectively; when the liver fat content of 5.0% was set as the cut-off value for the diagnosis of fatty liver, the sensitivity and specificity was 83.7% and 43.2%, respectively. Conclusions:The indexes of abdominal fat and liver fat measured by QCT in adults receiving physical examination are all positively correlated with body mass index. The effect of QCT in the diagnosis of obesity and fatty liver are both better than body mass index and ultrasound.

Objective:To analyze the distribution of body fat with quantitative computed tomography (QCT) in people with normal body mass index (BMI).Methods:A cross-sectional study was conducted in the physical examination population who underwent chest CT and QCT examination in the Department of Health Management, Henan Provincial People′s Hospital from January to December in 2021, and 1 395 physical examination subjects who met the inclusion criteria were selected as the research subjects. The subjects were divided into five groups according to their age. The general data of the subjects were collected. The total abdominal fat area (TFA), visceral fat area (VFA), subcutaneous fat area (SFA), total abdominal muscle area (TMA) and muscle fat content (MFC) in the subjects were measured by QCT. One-way analysis of variance, Welch test and Kruskal-Wallis test were used to compare the above QCT measurement indexes between the two genders among different age groups with normal BMI. Pearson correlation analysis was used to analyze the correlation between VFA and sarcopenia indexes. Multivariate linear regression was used to analyze the relationship between VFA and linear correlation variables in the related indicators of sarcopenia.Results:There were significant differences in TFA, VFA, TMA and SMI among different age groups in subjects with normal BMI (all P<0.05). Pearson correlation analysis showed that VFA was negatively correlated with TMA in some age groups (male: 18-39 years group: r=-0.351; 40-49 years group: r=-0.278; 60-69 years group: r=-0.245; female:40-49 years group: r=-0.251; 50-59 years group: r=-0.270;≥70 years group: r=-0.391; all P<0.01); it was negatively correlated with SMI (male: 18-39 years group: r=-0.352; 40-49 years group: r=-0.340; 50-59 years group: r=-0.266; 60-69 years group: r=-0.316; female: 40-49 years group: r=-0.240; 50-59 years group: r=-0.284; all P<0.001); it was positively correlated with MFC (male: 18-39 years group: r=0.342; 40-49 years group: r=0.291; female: 50-59 years group: r=0.133; 60-69 years group: r=0.284; all P<0.05). Multivariate linear regression analysis showed that VFA was independently and negatively correlated with SMI in both men and women after adjusting for age interference factors (male B=-1.881, t=-6.025, P<0.001; female B=-0.603, t=-2.887, P=0.004), and it was independently positively correlated with MFC (male B=1.230, t=4.271, P<0.001;female B=0.893, t=3.836, P<0.001). There was an independent negative correlation between VFA and TMA in male subjects ( B=0.263, t=2.478, P=0.013). Conclusions:VFA is correlated with TMA, SMI and MFC in people with normal BMI. Regardless of gender, SMI has a negative effect on VFA, and MFC has a positive effect on VFA.