[A retrospective cohort study of long-term nitrogen dioxide exposure and incident hypertension].

Objective: To investigate the effect of long-term exposure of nitrogen dioxide on the incidence of hypertension. Methods: From March to December 2009, 37 386 eligible residents from four cities in northern China (Tianjin, Shenyang, Taiyuan, and Rizhao) were enrolled in a follow-up study by using the random cluster sampling method. Demographic characteristics, lifestyle, history of diseases, and self-report situation of hypertension were collected by using questionnaire. Based on the average annual concentration of NO2 during the period from the cohort to the onset of hypertension as an estimate of exposure, the effect of NO2 exposure on hypertension was analyzed by employing Cox proportional hazards model. The interactions between NO2 exposure and different characteristics (age, sex, body mass index, smoking, alcohol consumption, education, economy, exercise, and fruit intake) were also examined. Results: The baseline age of residents was (43.74±13.78) years, and the body mass index (BMI) was (22.56±2.92) kg/m(2). During an average follow-up time of 11.40 years, 2 619 (7.0%) new cases of hypertension were reported. The overall mean environmental pollution levels during the study period for the entire cohort was (40.74±17.07) µg/m(3). After adjusting for age, sex, BMI, family history of hypertension, socio-economic information, and lifestyle, the hazard ratio (HR) of incident hypertension with a 10 µg/m(3) increase of NO2 was 1.21 (95%CI: 1.18-1.25). Compared with residents aged 60 years and over (HR=1.19, 95%CI: 1.14-1.26), former and current smoking (HR=1.20, 95%CI: 1.14-1.25), and high-frequency fruit consumption (HR=1.17, 95%CI: 1.13-1.21), residents younger than 60 years (HR=1.28, 95%CI: 1.25-1.32), non-smoker (HR=1.23, 95%CI: 1.19-1.27), and low-frequency fruit consumption (HR=1.27, 95%CI: 1.20-1.35) had stronger interaction effect with NO2 (all P values for interaction<0.05). Conclusion: NO2 exposure may lead to the onset of hypertension, which has a stronger effect on people younger than 60 years old, without smoking history and with low-frequency fruit consumption.

2,3,7,8-Tetrachlorodibezo-p-dioxin exposure and prostate cancer: a meta-analysis of cohort studies.

OBJECTIVE: To perform a meta-analysis of cohort studies and evaluate the association between exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and prostate cancer quantitatively. STUDY DESIGN: Publications before April 2012 about populations exposed to TCDD were searched in PubMed. Only cohort studies were included. Extraction and quality assessment of included articles was performed independently by two authors using the MOOSE guidelines. METHODS: A total of 17 cohort studies on prostate cancer with information about standardized mortality ratios (SMR), risk ratio (RR), standardized incidence ratios (SIR) and TCDD exposure were included. SMRs and RRs were pooled separately after weighing each study by calculating the inverse of the estimated variance. RESULTS: Based on the 13 reported SMRs or SIRs, the meta-analysis yielded a meta-SMR of 1.26 (95% confidence interval 1.00-1.57, P = 0.046). The meta-RR, based on four reported RR from four cohorts, was 1.04 (95% confidence interval 0.85-1.28). Begg's funnel plot showed little evidence of publication bias (Egger's test P-value = 0.817). CONCLUSION: This meta-analysis suggests that exposure to TCDD is associated with increased risk of prostate cancer.

Bulrush-like double perovskite: synthesis, tunneling magnetoresistance, and magnetocaloric effects.

The recent observation of room temperature tunneling magnetoresistance (TMR) in half-metallic A2FeMoO6 (A = Ca, Sr, Ba) double perovskites, and their importance to the emerging field of spintronics has led to considerable effort being dedicated to detailed investigations of the physical and chemical properties of these materials. This article will present an review of our recent investigations covering the synthesis, structures, magnetic and transport properties of "bulrush-like" A2FeMoO6 (A = Sr, Ba). Utilizing the high shape anisotropy as well as the reactivity of A2FeMoO6 to water and a sonochemical technique, we managed to manipulate the properties of grain boundary barriers, and thus put forward a new approach for the enhancement of room temperature TMR. The magnetocaloric effects of A2FeMoO6 double perovskites will also be discussed.

Psychological distress and type 2 diabetes mellitus: a 4-year policemen cohort study in China.

OBJECTIVES: This study investigated whether psychological distress predicts the development of type 2 diabetes mellitus (T2DM) and if the association differs between populations at a high or low diabetes risk level among Chinese police officers. DESIGN: Prospective cohort study. SETTING: Single centre. PARTICIPANTS: 6559 participants underwent clinical measurements at the hospital in April 2007. 5811 police officers participated in the follow-up consisting of new-onset diabetes (NOD) events occurring annually between 2008 and 2011. PRIMARY OUTCOME MEASURES: Baseline data were collected from policemen who completed the Symptom Checklist 90-Revised (SCL-90-R) questionnaire and a self-designed questionnaire. Psychological distress was measured by the SCL-90-R questionnaire. Hong Kong Chinese Diabetes Risk Score (HKCDRS) was used to evaluate the risk of T2DM, and the participants were divided into low-risk group and high-risk group based on the HKCDRS. Cox proportional hazards regression was used to calculate the HRs of the incidence of T2DM related to psychological distress and further stratified the analysis based on HKCDRS. RESULTS: Among 5811 participants, 179 subjects developed NOD during the 4-year follow-up. 54 subjects (1.63%) with a HKCDRS 0-7 vs 125 subjects (4.98%) with a HKCDRS>7 developed NOD (p<0.05). There was a significant association between psychological distress and T2DM (HR=1.46; 95% CI 1.05 to 2.02). Among the participants with a high-risk score (HKCDRS>7), 7.07% of those with psychological distress developed T2DM compared with 4.43% of participants without psychological distress (p<0.05). The corresponding adjusted HR for psychological distress was 1.61 (95% CI 1.10 to 2.37). CONCLUSIONS: Psychological distress is an independent risk factor for T2DM in this prospective cohort study. Stratification analysis indicated that psychological distress was associated with T2DM in a high-risk level population.

Chemical synthesis and magnetic properties of well-coupled FePt/Fe composite nanotubes.

A simple two-step hydrogen reduction method was used to synthesize FePt/Fe composite nanotubes. As the first step, L1(0) FePt nanotubes were prepared by heating a porous alumina template loaded with an alcohol solution of a Fe chloride and Pt chloride mixture in flowing hydrogen at 670 degrees C. Then, FePt/Fe composite nanotubes were obtained by reducing the alcohol solution of the Fe chloride within the formed FePt nanotubes at a lower temperature, namely 470 degrees C. Through changing the concentrations of initial alcohol solutions, the FePt:Fe atomic ratios of the composite nanotubes were easily adjusted and the magnetic properties were tuned accordingly. For (FePt)(100-x)/Fe(x) composite nanotubes with x ranging between 0 and 26 at.%, the hard and soft phases were well coupled and the coercivity was tunable over a large range (1.27-2.73 T). Furthermore, the marked interdiffusion between Fe and FePt, which usually exists in FePt-based composites fabricated by using conventional methods, was not observed in the formed composite nanotubes. This indicates the two-step hydrogen reduction method to be a promising route for synthesizing nanocomposites which are difficult to fabricate by using conventional methods due to the interdiffusion between different phases.

Blood lipid concentrations of dioxins and dibenzofurans causing chloracne.

Chloracne is caused by exposure to certain halogenated polycyclic hydrocarbons such as polychlorinated dibenzodioxins (PCDDs) and dibenzofurans (PCDFs). In chronic exposure it is not known what level of intoxication, represented by the level in blood lipids, is sufficient to cause chloracne. Blood levels of the congeners of PCDD/Fs were determined in four groups of humans. One group had clinically visible chloracne due to exposure in a hexachlorobenzene workshop of a large chemical factory. A second group was exposed in the same workshop, but had no skin changes. There were two control groups: one non-exposed group of maintenance workers from the same chemical factory, and one group of healthy individuals living elsewhere. Blood levels were converted to toxicity equivalents of tetrachlorodibenzo-p-dioxin (TCDD). In the chloracne group blood levels in toxicity equivalents (TEQs) ranged from 1168 to 22,308 pg/g blood lipid. In the exposed without chloracne this ranged from 424 to 662 pg/g. It is concluded that the level to develop chloracne is between 650 and 1200 pg/g TEQ. The contribution of TCDD was rather small, and the main causative congeners were the hexachlorinated dibenzodioxins and dibenzofurans (HxCDD/Fs); lipid-based blood levels in absolute amounts that may cause chloracne are in the range of 2-3.5 ng/g HxCDD, and 2-5 ng/g HxCDF.

Morphometry of pig coronary arterial trees.

To establish a mathematical model of the tree like arteries for the purpose of hemodynamic analysis, a complete set of morphometric data of pig coronary arteries is presented. For the purpose of mathematical modeling, three innovations in morphometry are introduced: 1) a rule for assigning the order numbers of the vessels on the basis of diameter ranges, 2) a connectivity matrix to describe asymmetric branching, and 3) a measurement of the fraction of vessel segments connected in series. The morphometric measurements were made with the silicone elastomer-casting method. Data on smaller vessels were obtained from histological specimens by optical sectioning. Data on larger vessels were obtained from vascular casts. The order number, diameter, length, connectivity matrix, and fractions of the vessels of a given order connected in series were measured for all orders of vessels of the right coronary artery and the left anterior descending and left circumflex branches. The data can be used to analyze the longitudinal distribution of blood pressure and volume and spatial distribution of perfusion in myocardium.