Evidence of Spatially Extensive Resistance to PCBs in an Anadromous Fish of the Hudson River

Populations of organisms that are chronically exposed to high levels of chemical contaminants may not suffer the same sublethal or lethal effects as naive populations, a phenomenon called resistance. Atlantic tomcod (Microgadus tomcod) from the Hudson River, New York, are exposed to high concentrations of polycyclic aromatic hydrocarbons (PAHs) and bioaccumulate polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs). They have developed resistance to PCBs and PCDDs but not to PAHs. Resistance is largely heritable and manifests at early-life-stage toxic end points and in inducibility of cytochrome P4501A (CYP1A) mRNA expression. Because CYP1A induction is activated by the aryl hydrocarbon receptor (AHR) pathway, as are most toxic responses to these compounds, we sought to determine the geographic extent of resistance to CYP1A mRNA induction by PCBs in the Hudson River tomcod population. Samples of young-of-the-year tomcod were collected from seven locales in the Hudson River, extending from the Battery at river mile 1 (RM 1) to RM 90, and from the Miramichi River, New Brunswick, Canada. Laboratory-reared offspring of tomcod adults from Newark Bay, in the western portion of the Hudson River estuary, were also used in this study. Fish were partially depurated in clean water and intraperitoneally injected with 10 ppm coplanar PCB-77, 10 ppm benzo[a]pyrene (BaP), or corn oil vehicle, and levels of CYP1A mRNA were determined. CYP1A was significantly inducible by treatment with BaP in tomcod from the Miramichi River, from laboratory-spawned offspring of Newark Bay origin, and from all Hudson River sites spanning 90 miles of river. In contrast, only tomcod from the Miramichi River displayed significantly induced CYP1A mRNA expression when treated with PCB-77. Our results suggest that the population of tomcod from throughout the Hudson River estuary has developed resistance to CYP1A inducibility and probably other toxicities mediated by the AHR pathway. Tomcod from the Hudson River may represent the most geographically expansive population of vertebrates with resistance to chemical pollutants that has been characterized

Prevalence and risk factors for prehypertension and hypertension among adults in Central China from 2000-2011

Background: Hypertension is frequently studied in surveys; however, prehypertension, a new blood pressure status between normotension and hypertension, is rarely reported. Methods: All data were derived from the China Health and Nutrition Survey (CHNS) and were analysed by logistic regression for correlation. Results: The prehypertension prevalence was 27.4%, with a hypertension rate of 36.9%. The awareness, treatment, and uncontrolled rates among all hypertension participates were 19.8%, 83.6%, and 55.0%, respectively. The epidemic rate of hypertension increased with increasing age (p < 0.001), and prehypertension appeared to have an epidemic peak in the age group of 38–57 years (p < 0.001). In general, the incidence of hypertension in urban participants was higher than in rural subjects (p < 0.001), and prehypertension in urban subjects was lower than that in rural subjects (p < 0.001). According to the results of logistic regression, hypertension and prehypertension were associated with age, gender, location, body mass index (BMI), body fat rate (BFR), waist circumference (WC), education, and the intake of energy-yielding nutrients<0.05). Conclusion: The current study reveals a high epidemic rate of hypertension and prehypertension in Central China. These results indicate the urgent need to develop strategies to improve the prevention of hypertension and prehypertension in Central China

Highly-Efficient and Visible Light Photocatalytical Degradation of Organic Pollutants Using TiO2-Loaded on Low-Cost Biomass Husk

A composite composing of TiO2 nanoparticles load on biomass rice husk (RH) is developed by directly growing TiO2 nanoparticles on RH. The in-situ growth of the nanocrystals on RH is achieved by a low-cost and one-step homogeneous precipitation. Rapid hydrolysis proceeds at 90 &deg;C by using ammonium fluotitanate and urea to facilitate the selective growth of TiO2. The method provides an easy access to the TiO2-RH composite with a strong interaction between TiO2 nanoparticles and the underlying RH. The structure and composition of TiO2-RH are characterized by using X-ray diffraction, X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, and UV-vis absorption spectroscopy. TiO2 nanoparticles-RH exhibits a good photocatalytic degradation of methyl orange. The results show that 92% of methyl orange (20 mg L&minus;1) can be degraded within three hours in visible light. The catalytic activity of the composite is not reduced after 6 cycles, and it still reaches 81% after 6 cycles. The enhanced performance is ascribed to the suitable particle size the good dispersibility. It is expected that the high photocatalytical performance and the cost-effective composite presented here will inspire the development of other high-performance photocatalysts

Perfluorooctanoic Acid (PFOA) Exposure in Early Life Increases Risk of Childhood Adiposity: A Meta-Analysis of Prospective Cohort Studies

Some articles have examined perfluorooctanoic acid (PFOA) exposure in early life in relation to risk of childhood adiposity. Nevertheless, the results from epidemiological studies exploring the associations remain inconsistent and contradictory. We thus conducted an analysis of data currently available to examine the association between PFOA exposure in early life and risk of childhood adiposity. The PubMed, EMBASE, and Web of Science databases were searched to identify studies that examined the impact of PFOA exposure in early life on childhood adiposity. A random-effects meta-analysis model was used to pool the statistical estimates. We identified ten prospective cohort studies comprising 6076 participants with PFOA exposure. The overall effect size (relative risk or odds ratio) for childhood overweight was 1.25 (95% confidence interval (CI): 1.04, 1.50; I2 = 40.5%). In addition, exposure to PFOA in early life increased the z-score of childhood body mass index (&beta; = 0.10, 95% CI: 0.03, 0.17; I2 = 27.9%). Accordingly, exposure to PFOA in early life is associated with an increased risk for childhood adiposity. Further research is needed to verify these findings and to shed light on the molecular mechanism of PFOA in adiposity

Bibliometric Analysis Reveals the Progress of PM_2.5 in Health Research, Especially in Cancer Research

PM2.5 has an aerodynamic diameter of less than or equal to 2.5 microns due to its inherent physical and chemical properties so that it can enter the alveoli through the respiratory tract for blood gas exchange. Numerous studies have shown that PM2.5 is a serious air pollutant that poses a wide range of health risks, especially for cancer. Bibliometric methods were employed to have comprehensively analyzed the research of PM2.5 in cancer for about a decade in Web of Science to identify hotspots and trends using VOSviewer, CiteSpace, and R. The field has undergone overall growth in the past decade. As research on PM2.5 in health deepens, cancer related to it expanded beyond the respiratory system to the digestive system, urinary system, female gonadal axis, breast cancer and other cancers. Another observation is that research on PM2.5 in cancer has progressed in the mechanisms of deterioration, such as the role of matrix metalloproteinases in cancer. In addition, research on the risks of PM2.5 in combination with polycyclic aromatic hydrocarbons and heavy metals has also emerged. Results showed that there are relatively more studies on PM2.5 in high-latitude countries, which may be due to different national conditions, such as climate and coal combustion. Our research has combed through the progress of PM2.5 in cancer research and provided a supplement for developing pollution prevention ideas with different national conditions in this field

High‐Temperature Stability Amorphous Ternary AlBN Dielectric Films on N ⁺⁺ GaN

International audienceDielectric films have played a vital role in the development of micro- and nanoelectronic devices over the past decades. However, the stability of current dielectrics under extreme high-temperature conditions is still a major shortcoming to be overcome. Herein, the successful fabrication of high-quality amorphous ternary AlBN dielectric films on n++GaN substrates by pulsed laser deposition (PLD) at room temperature (25 ± 2 °C) is reported. Systematic characterizations on the morphology, structure, chemical composition, and band offsets properties of the fabricated films reveal that both as-deposited and 800 °C postdeposition annealing (PDA) thin films are amorphous and exhibit good physical and electrical properties. Large band offsets (>2.0 eV), high dielectric constants (>10), and low leakage currents are achieved in both cases. Furthermore, the leakage current density in the Au/AlBN/n++GaN junctions of 800 °C PDA thin films is reduced by approximately one order of magnitude compared with those of as-deposited thin films. The demonstration of these excellent properties indicates that the amorphous AlBN dielectric thin films are promising candidates for integrated dielectric layers in electronic devices for harsh environment application