Mediating effect of body fat percentage in the association between ambient particulate matter exposure and hypertension: a subset analysis of China hypertension survey.

BACKGROUND: Hypertension caused by air pollution exposure is a growing concern in China. The association between air pollutant exposure and hypertension has been found to be potentiated by obesity, however, little is known about the processes mediating this association. This study investigated the association between fine particulate matter (aerodynamic equivalent diameter ≤ 2.5 microns, PM2.5) exposure and the prevalence of hypertension in a representative population in southern China and tested whether obesity mediated this association. METHODS: A total of 14,308 adults from 48 communities/villages in southern China were selected from January 2015 to December 2015 using a stratified multistage random sampling method. Hourly PM2.5 measurements were collected from the China National Environmental Monitoring Centre. Restricted cubic splines were used to analyze the nonlinear dose-response relationship between PM2.5 exposure and hypertension risk. The mediating effect mechanism of obesity on PM2.5-associated hypertension was tested in a causal inference framework following the approach proposed by Imai and Keele. RESULTS: A total of 20.7% (2966/14,308) of participants in the present study were diagnosed with hypertension. Nonlinear exposure-response analysis revealed that exposure to an annual mean PM2.5 concentration above 41.8 µg/m3 was associated with increased hypertension risk at an incremental gradient. 9.1% of the hypertension burden could be attributed to exposure to elevated annual average concentrations of PM2.5. It is noteworthy that an increased body fat percentage positively mediated 59.3% of the association between PM2.5 exposure and hypertension risk, whereas body mass index mediated 34.3% of this association. CONCLUSIONS: This study suggests that a significant portion of the estimated effect of exposure to PM2.5 on the risk of hypertension appears to be attributed to its effect on alterations in body composition and the development of obesity. These findings could inform intersectoral actions in future studies to protect populations with excessive fine particle exposure from developing hypertension.

Zinc in soil reflecting the intensive coal mining activities: Evidence from stable zinc isotopes analysis.

In the mining area affected by coal mining activities for a long time, heavy metal Zn pollution poses a serious threat to soil quality and human health, and direct evidence showing the relationship between Zn accumulation mechanism in soils and mining activities is lacking. In this study, the Zn content and isotopes composition (δ66Zn) from soil and environmental samples around mining area were determined and analyzed to clarify the Zn characteristics in soil. Moreover, the distribution and source of Zn content in soil of mining area were analyzed by mathematical statistics, correlation analysis and isotope mass mixing model. The results showed that: (1) the Zn content in soil ranged from 95 to 327 mg·kg-1 (mean: 233 mg·kg-1), exceeding the control point and the soil background value of Anhui Province; (2) the results of Zn isotope analysis showed that Zn in soil mainly derived from the wind dispersion input of fine particles in gangue and fly ash, followed by the natural weathering of parent material; (3) isotopic mass mixing model can be used to distinguish the contribution of anthropogenic and natural Zn sources. Mining input was the main contribution source of Zn in soil (mean: 67%), followed by natural background (mean: 33%). The employment of Zn isotopes can effectively evaluate the impact of anthropogenic and natural long-term processes on Zn in the soil of the mining area, and provide important information for the formulation of soil metal pollution control measures.

Prognostic value of cartilage intermediate layer protein 1 in chronic heart failure.

AIMS: Emerging evidence suggests that cartilage intermediate layer protein 1 (CILP-1) is associated with myocardial remodelling. However, the prognostic value of circulating CILP-1 in patients with heart failure (HF) remains to be elucidated. This study aimed to investigate whether circulating CILP-1 can independently predict the outcome of chronic HF. METHODS AND RESULTS: This prospective cohort study included 210 patients with chronic HF and left ventricular ejection fraction <50% between September 2018 and December 2019. The primary endpoint was 1 year all-cause mortality. During the 1 year follow-up, 28 patients died. In multivariable Cox proportional hazards regression analysis, higher CILP-1 levels were independently associated with a higher risk of mortality after adjusting for potential confounding factors. In Kaplan-Meier analysis, patients with CILP-1 levels above the median had a significantly higher mortality rate than those with CILP-1 levels below the median (log-rank P = 0.015). In addition, CILP-1 significantly improved prognostic prediction over N-terminal pro-brain natriuretic peptide by an increase in net reclassification improvement (P = 0.043) and a trend towards an increase in integrated discrimination improvement (P = 0.118). CONCLUSIONS: Circulating CILP-1 is a novel independent prognostic predictor in chronic HF.

Acute thoracic aortic dissection (stanford type B) complicated with acute renal failure.

We report a recent case and review some literatures of acute aortic dissection (AAD) Stanford type B complicated with late onset of acute renal failure. The patient underwent preoperational peritoneal dialysis followed by thoracic endovascular aortic repair (TEVAR) and was fully recovered and discharged soon after surgery. We conclude that an AAD case is difficult to achieve a timely diagnosis, but with attention to systemic symptoms and dedication thorough treatment plan, a full recovery and positive prognosis are expected.