[Prospective association between physical activity and mortality in patients with chronic kidney disease]

Objective: To investigate the prospective association of physical activity with all-cause, cardiovascular disease (CVD), and chronic kidney disease (CKD) mortality in CKD patients in China. Methods: Cox proportional hazard models were used to evaluate the association of total, domain-specific, and intensity-specific physical activity with the risk of all-cause, CVD, and CKD mortality based on data from the baseline survey of China Kadoorie Biobank. Results: During a median follow-up of 11.99 (11.13, 13.03) years, there were 698 deaths in 6 676 CKD patients. Compared with the bottom tertile of total physical activity, participants in the top tertile had a lower risk of all-cause, CVD, and CKD mortality, with hazard ratios (HRs) (95%CIs) of 0.61 (0.47-0.80), 0.40 (0.25-0.65), and 0.25 (0.07-0.85), respectively. Occupational, commuting, and household physical activity were negatively associated with the risk of all-cause and CVD mortality to varying degrees. Participants in the top tertile of occupational physical activity had a lower risk of all-cause (HR=0.56, 95%CI: 0.38-0.82) and CVD (HR=0.39, 95%CI: 0.20-0.74) mortality, those in the top tertile of commuting physical activity had a lower risk of CVD mortality (HR=0.43, 95%CI: 0.22-0.84), and those in the top tertile of household physical activity had a lower risk of all-cause (HR=0.61, 95%CI: 0.45-0.82), CVD (HR=0.44, 95%CI: 0.26-0.76) and CKD (HR=0.03, 95%CI: 0.01-0.17) mortality, compared with the bottom tertile of corresponding physical activity. No association of leisure-time physical activity with mortality was observed. Both low and moderate-vigorous intensity physical activity were negatively associated with the risk of all-cause, CVD and CKD mortality. The corresponding HRs (95%CIs) were 0.64 (0.50-0.82), 0.42 (0.26-0.66) and 0.29 (0.10-0.83) in the top tertile of low intensity physical activity, and the corresponding HRs (95%CIs) were 0.63 (0.48-0.82), 0.39 (0.24-0.64) and 0.23 (0.07-0.73) in the top tertile of moderate-vigorous intensity physical activity. Conclusion: Physical activity can reduce the risk of all-cause, CVD, and CKD mortality in CKD patients.

[Prevalence of chronic kidney disease and its association with lifestyle factors in adults from 10 regions of China]

Objective: To investigate the distribution of chronic kidney disease (CKD) in participants from the China Kadoorie Biobank (CKB) study and evaluate the association between lifestyle risk factors and CKD. Methods: Based on the baseline survey data and follow-up data (as of December 31, 2018) of the CKB study, the differences in CKD cases' area and population distributions were described. Cox proportional hazards regression model was used to estimate the association between lifestyle risk factors and the risk of CKD. Results: A total of 505 147 participants, 4 920 cases of CKD were recorded in 11.26 year follow up with a incidence rate of 83.43/100 000 person-years. Glomerulonephropathy was the most common type. The incidence of CKD was higher in the urban area, men, and the elderly aged 60 years and above (87.83/100 000 person-years, 86.37/100 000 person-years, and 132.06/100 000 person-years). Current male smokers had an increased risk for CKD compared with non-smokers or occasional smokers (HR=1.18, 95%CI: 1.05-1.31). The non-obese population was used as a control group, both general obesity determined by BMI (HR=1.19, 95%CI: 1.10-1.29) and central obesity determined by waist circumference (HR=1.27, 95%CI: 1.19-1.35) were associated with higher risk for CKD. Conclusion: The risks for CKD varied with area and population in the CKB cohort study, and the risk was influenced by multiple lifestyle factors.

[Correlation between sleep status and frailty in adults aged 30-79 years in China]

Objective: To explore the correlation between sleep status and frailty in adults aged 30-79 years in China, and explore the potential effect modification of general and central obesity. Methods: Based on the baseline data of the China Kadoorie Biobank, we used multinomial logistic regression to analyze the correlation between long and short sleep duration, insomnia disorder, snoring, and unhealthy sleep score with risks of pre-frailty and frailty. Both overall and obesity-stratified analyses were performed. Result: Among the 512 724 participants, 2.3% had frailty and 40.1% had pre-frailty. There was a U-shaped relationship between sleep duration and frailty score. Short (OR=1.21, 95%CI: 1.19-1.23) or long sleep duration (OR=1.19, 95%CI: 1.17-1.21), insomnia disorder (OR=2.09, 95%CI: 2.02-2.17), and snoring (OR=1.61, 95%CI: 1.59-1.63) were all positively correlated with pre-frailty, and dose-response relationships were observed between unhealthy sleep score and pre-frailty (P for trend<0.001), with OR values of 1.46 (1.44-1.48), 1.97 (1.93-2.00) and 3.43 (3.21-3.67) respectively for those having unhealthy sleep score of 1 to 3. These sleep problems were also positively correlated with frailty. Compared with the overweight or obesity group, stronger relationships were observed between short sleep duration and frailty or pre-frailty and between insomnia disorder and pre-frailty, while the relationships between snoring and frailty and pre-frailty were weaker in the participants with normal weight (P for interaction <0.007 for all). We also observed similar effect modification by central obesity. Conclusion: Long or short sleep duration, insomnia disorder, snoring and higher unhealthy sleep scores were positively correlated with pre-frailty or frailty, general and central obesity status could modify the relationships.

[Experimental research on permeability injury of pulmonary microvascular endothelial cells monolayer induced by tumor necrosis factor]

AIM AND METHODS

To investigate the mechanism of tumor necrosis factor (TNF) induced permeability injury of rat pulmonary microvascular endothelial cells (RPMVEC) monolayer, the effect of TNF on permeability of RPMVEC monolayer was examined with microfilter and the effect of TNF on RPMVEC F-actin was observed with immunocytochemistry. The interfering action of formoterol, anisodamine and cholera toxin on permeability and F-actin changes induced by TNF was also observed.

RESULTS

(1) TNF induced significant increase in permeability of RPMVEC monolayer 30, 60 and 90 minutes after treatment with TNF. (2) F-actin in RPMVEC depolymerized 90 minutes after treatment with TNF. Permeability and F-actin did not change significantly when formoterol, anisodamine or cholera toxin was added separately.

CONCLUSION

TNF can induce permeability injury of RPMVEC monolayer, which is correlated with depolymerization of F-actin. Formoterol, anisodamine and cholera toxin can inhibit the permeability change induced by TNF which may due to their inhibition to the distribution change of F-actin.

Synthesis and bioactivities of new LHRH antagonists containing a novel unnatural amino acids at position five

Synthesis and bioactivities of new antagonists of luteinizing hormone releasing hormone (LHRH) with novel unnatural amino acids at position five are reported. Most of them showed some antiovulatory activity at 0.5 microgram/rat and two of them inhibited ovulation completely at 1 microgram/rat using saline as vehicle.

Antagonists of luteinizing hormone releasing hormone with novel unnatural amino acids at position six

Five new antagonists of luteinizing hormone releasing hormone (LHRH) containing novel unnatural amino acids at position six are reported. They are very effective in the rat antiovulatory assay. Using saline as vehicle, antagonist-[N-Ac-D-2-Nal1, D-4-Cl-Phe2, D-3-Pal3, Arg5, D-A26, D-Ala10]-LHRH inhibited ovulation completely at 1 micrograms/rat and three of the other antagonists showed some antiovulatory activity at 0.5 micrograms/rat.