47 research outputs found

    Interaction effects of polyfluoroalkyl substances and sex steroid hormones on asthma among children

    Get PDF
    To evaluate the interactions between polyfluoroalkyl substances (PFASs) and reproductive hormones and associated asthma, a total of 231 asthmatic and 225 non-asthmatic adolescents were selected from northern Taiwan in the Genetic and Biomarkers study for Childhood Asthma from 2009-2010. The interaction between PFASs and reproductive hormones on asthma was analyzed with a two-level binary logistic regression model. The results showed that, among asthmatics, PFASs were positively associated with estradiol levels and negatively associated with testosterone levels. However, only significant association was identified for PFNA and estradiol in control group. After controlling for hormone levels, associations between PFAS exposure and asthma were consistently stronger among children with higher than lower estradiol, with odds ratios (OR) for asthma ranging from 1.25 for PFOS (95% Confidence Interval [CI]: 0.90, 1.72) to 4.01 for PFDA (95% CI: 1.46, 11.06) among boys and 1.25 for PFOS (95% CI: 0.84, 1.86) to 4.16 for PFNA (95% CI: 1.36, 12.73) among girls. Notably, the interactions between estradiol and PFASs were significant for PFOS (p = 0.026) and PFNA (p = 0.043) among girls. However, testosterone significantly attenuated the association between PFOS and asthma across sex. In conclusions, our findings suggested that reproductive hormones amplify the association between PFASs and asthma among adolescents

    Ambient air pollution in relation to diabetes and glucose-homoeostasis markers in China: a cross-sectional study with findings from the 33 Communities Chinese Health Study

    Get PDF
    Background: Health effects of air pollution on diabetes have been scarcely studied in developing countries. We aimed to explore the associations of long-term exposure to ambient particulate matter (PM) and gaseous pollutants with diabetes prevalence and glucose-homoeostasis markers in China. Methods: Between April 1 and Dec 31, 2009, we recruited a total of 15 477 participants aged 18–74 years using a random number generator and a four-staged, stratified and cluster sampling strategy from a large cross-sectional study (the 33 Communities Chinese Health Study) from three cities in Liaoning province, northeastern China. Fasting and 2 h insulin and glucose concentrations and the homoeostasis model assessment of insulin resistance index and β-cell function were used as glucose-homoeostasis markers. Diabetes was defined according to the American Diabetes Association's recommendations. We calculated exposure to air pollutants using data from monitoring stations (PM with an aerodynamic diameter of 10 μm or less [PM10], sulphur dioxide, nitrogen dioxide, and ozone) and a spatial statistical model (PM with an aerodynamic diameter of 1 μm or less [PM1] and 2·5 μm or less [PM2·5]). We used two-level logistic regression and linear regression analyses to assess associations between exposure and outcomes, controlling for confounders. Findings: All the studied pollutants were significantly associated with increased diabetes prevalence (eg, the adjusted odds ratios associated with an increase in IQR for PM1, PM2·5, and PM10 were 1·13, 95% CI 1·04–1·22; 1·14, 1·03–1·25; and 1·20, 1·12–1·28, respectively). These air pollutants were also associated with higher concentrations of fasting glucose (0·04–0·09 mmol/L), 2 h glucose (0·10–0·19 mmol/L), and 2 h insulin (0·70–2·74 μU/L). No association was observed for the remaining biomarkers. Stratified analyses indicated greater effects on the individuals who were younger (<50 years) or overweight or obese. Interpretation: Long-term exposure to air pollution was associated with increased risk of diabetes in a Chinese population, particularly in individuals who were younger or overweight or obese. Funding: The National Key Research and Development Program of China, the National Natural Science Foundation of China, the Fundamental Research Funds for the Central Universities, the Guangdong Province Natural Science Foundation, the Career Development Fellowship of Australian National Health and Medical Research Council, and the Early Career Fellowship of Australian National Health and Medical Research Council

    Exposures to particulate matters and childhood sleep disorders—A large study in three provinces in China

    Get PDF
    Objectives: Evidence on the link between long-term ambient particulate matter (PM) exposures and childhood sleep disorders were scarce. We examined the associations between long-term exposures to PM2.5 and PM1 (PM with an aerodynamic equivalent diameter <2.5 μm and <1 μm, respectively) with sleep disorders in children. Methods: We performed a population-based cross-sectional survey in 177,263 children aged 6 to 18 years in 14 Chinese cities during 2012–2018. A satellite-based spatiotemporal model was employed to estimate four-year annual average PM2.5 and PM1 exposures at residential and school addresses. Parents or guardians completed a checklist using the Sleep Disturbance Scale for Children. We estimated the associations using generalized linear mixed models with adjustment for characteristics of children, parents, and indoor environments. Results: Long-term PM2.5 and PM1 exposures were positively associated with odds of sleep disorders for almost all domains. For example, increments in PM2.5 and PM1 per 10 μg/m3 were associated with odds ratios of global sleep disorder of 1.24 (95 % confidence interval [CI]: 1.14, 1.35) and 1.31 (95 %CI: 1.18, 1.46), respectively. Similar results were observed for subtypes of sleep disorder. These associations were heterogeneous regionally, with stronger associations among children residing in southeast region than in northeast and northwest regions. Moreover, larger estimates of PM1 were found than that of PM2.5 in southeast region. Conclusion: Long-term PM2.5 and PM1 exposures are independently associated with higher risks of childhood sleep disorders, and these associations vary by geographical region

    Research on the Tourism Space Structure in Lingui District of Guilin Based on the Development and Utilization of Landscape Resources

    No full text
    The 257 scenic spots in Lingui covered 5 main categories, 14 sub-categories and 26 basic types, in which there were 33 natural scenic spots and 224 humanistic scenic spots, featured by rich resources stock, humanistic landscape resources-based, and significant space agglomeration; the quality levels are 11 high-quality scenic spots that most of them have been developed, 57 good scenic spots and 189 ordinary scenic spots that have big development potential; of the 36 scenic spots developed so far, 7 are natural, and 29 are humanistic(22 of them have been oriented by cultural relic protection sites); from initial scattered-point to intensive scattered-point to point-axis period, they showed stepped and multi-center structure situation. We found that: 1) five levels of growth pole have been formed; 2) The influence mechanism of development on tourism space is: the theme park is the greatest, the natural landscape resources is secondary and the cultural landscape resources is the least, the former-residence -type cultural relics protection sites and traditional villages have a certain influence, and the influence of high-level landscape resources is big in general. Based on the above results, we can build the tourism space structure with “one ring, one core, one sub-core, and three axes”

    Research on the Tourism Space Structure in Lingui District of Guilin Based on the Development and Utilization of Landscape Resources

    No full text
    The 257 scenic spots in Lingui covered 5 main categories, 14 sub-categories and 26 basic types, in which there were 33 natural scenic spots and 224 humanistic scenic spots, featured by rich resources stock, humanistic landscape resources-based, and significant space agglomeration; the quality levels are 11 high-quality scenic spots that most of them have been developed, 57 good scenic spots and 189 ordinary scenic spots that have big development potential; of the 36 scenic spots developed so far, 7 are natural, and 29 are humanistic(22 of them have been oriented by cultural relic protection sites); from initial scattered-point to intensive scattered-point to point-axis period, they showed stepped and multi-center structure situation. We found that: 1) five levels of growth pole have been formed; 2) The influence mechanism of development on tourism space is: the theme park is the greatest, the natural landscape resources is secondary and the cultural landscape resources is the least, the former-residence -type cultural relics protection sites and traditional villages have a certain influence, and the influence of high-level landscape resources is big in general. Based on the above results, we can build the tourism space structure with “one ring, one core, one sub-core, and three axes”

    Discussion on the Sustainable Development Pattern of Road Network Structure of Cities with a Population of 1-2 Million in China

    No full text
    The urban road network system is the main carrier of urban traffic. The constraint factor that urban road network has on traffic leads to major urban traffic problems. In this paper, a questionnaire survey and the Delphi method are determined to determine the case cities with a population of 1-2 million at home and abroad. Literature research and comparative, analytical, and inductive research methods are used to compare, analyse, and evaluate the advantages and disadvantages of the road network structure of the case cities, to summarize the development law of the urban road network, and to propose a sustainable development structure model for each development stage of urban road network: the mode made of ring freeway + trunk street (the embryonic stage), the mode made of ring freeway + expressway + trunk street (the incubation stage), the mode made of outer ring freeway + outer ring expressway and radial expressway + trunk street (the mature stage). The innovative point of this paper is to put forward a sustainable development pattern for the road network structure of cities with a population of 1-2 million in China

    Isomers of perfluorooctanesulfonate (PFOS) in cord serum and birth outcomes in China: Guangzhou Birth Cohort Study

    No full text
    Prior investigations on the associations of polyfluoroalkyl substances (PFASs) with fetal growth are mixed. Moreover, little research has accrued pertaining to the association between isomers of PFASs with gestational age and birth weight. To address this gap and present novel information, we conducted a study including 321 pairs of mothers and their infants recruited from Guangzhou, China. High performance liquid chromatography-mass spectrometry was utilized to analyze isomers of perfluorooctanesulfonate (PFOS), perfluorooctanoate (PFOA) along with other PFAS levels in cord serum samples. Mothers' and infants' characteristics were gathered from medical records. The resulting data revealed that higher PFOS, PFOA and isomers of PFOS were associated with lower birth weight. Per ln-unit (ng/mL) increase in cord serum total branched PFOS isomers was associated with a 126.3 g (95% CI: − 195.9, − 56.8) reduction in the weight of infants at birth, while an ln-unit (ng/mL) increase of serum linear PFOS isomers (n-PFOS) was associated with a 57.2 g (95% CI: − 103.1, − 11.3) reduction in the weight of infants at birth upon the subsequent adjustment for potential confounding variables. Notably, the association between cord PFAS level and birth weight was more pronounced in male infants. Furthermore, a positive association among branched PFOS isomers (1m-PFOS and 3 + 4 + 5m-PFOS) and gestational age was found. No associations could be found among other PFASs in conjunction with gestational age or birth weight. In conclusion, this investigation suggests that higher PFAS concentrations are associated with lower birth weight, and branched PFOS isomers show greater impact on infant birth weight than linear PFOS

    Housing characteristics, home environmental factors, and pulmonary function deficit in Chinese children: Results from the Seven Northeast Cities (SNEC) Study

    No full text
    To assess the effects of housing characteristics and home environmental factors on lung function of Chinese children, 6740 children (aged 6–16 years) were recruited from seven cities in Northeast China in 2012. Performance of lung function was determined by comparison of forced vital capacity (FVC), forced expiratory volume (FEV1), peak expiratory flow (PEF), and maximal mid-expiratory flow (MMEF). Multivariate regression models were used to evaluate the associations with lung function deficit. The results showed that housing conditions were associated with lung function deficit in children. The adjusted odds ratios were 0.47 (95% CI: 0.26–0.83) for FVC for “ping-fang” housing compared with “dan-yuan-lou-fang” housing and 2.90 (95% CI: 2.43–3.47) for FEV1 with home renovations completed within two years compared with counterparts. The linear regression models consistently showed a significant association of housing conditions and home environmental factors with lung function measurements across subjects. A residence taller than seven stories was negatively associated with FEV1 (β = −55; 95% CI: −97 to −13). In conclusion, housing conditions and home environmental factors are particularly important to the development of lung function and respiratory health in children. These factors are concerning and action should be taken to improve them

    Rosmarinic Acid Attenuates Airway Inflammation and Hyperresponsiveness in a Murine Model of Asthma

    No full text
    Rosmarinic acid (RA) has numerous pharmacologic effects, including anti-oxidant, anti-inflammatory, and analgesic effects. This study aimed to evaluate the preventive activity of RA in a murine model of asthma and to investigate its possible molecular mechanisms. Female BALB/c mice sensitized and challenged with ovalbumin (Ova) were pretreated with RA (5, 10 or 20 mg/kg) at 1 h before Ova challenge. The results demonstrated that RA markedly inhibited increases in inflammatory cells and Th2 cytokines in the bronchoalveolar lavage fluid (BALF), significantly reduced the total IgE and Ova-specific IgE concentrations, and greatly ameliorated airway hyperresponsiveness (AHR) compared with the control Ova-induced mice. Histological analyses showed that RA substantially decreased the number of inflammatory cells and mucus hypersecretion in the airway. In addition, our results suggested that the protective effects of RA might be mediated by the suppression of ERK, JNK and p38 phosphorylation and activation of nuclear factor-κB (NF-κB). Furthermore, RA pretreatment resulted in a noticeable reduction in AMCase, CCL11, CCR3, Ym2 and E-selectin mRNA expression in lung tissues. These findings suggest that RA may effectively delay the progression of airway inflammation
    corecore