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Short-term effects of ambient air pollution and cardiovascular events in Shiraz, Iran, 2009 to 2015
2019
Soleimani, Zahra | Darvishi Boloorani, Ali | Khalifeh, Reza | Griffin, Dale W. | Mesdaghinia, Alireza
Air pollution and dust storms are associated with increased cardiovascular hospital admissions. The aim of this study was to investigate the association between short-term exposure to ambient air pollutants and CVD (cardiovascular disease) events in a long-term observational period. The study included the events of cardiovascular diseases (namely coronary artery disease, ischemic heart disease, myocardial infarction, and pneumo thrombo embolism) within the population of Shiraz, from March 21, 2009 to March 20, 2015. Also, each patient’s demographics were recorded. Main meteorological variables and five ambient pollutants (CO, O₃, SO₂, NO₂, and PM₁₀) were recorded. Statistical analysis was performed using linear regression (GLM) and a generalized additive model (GAM) estimating Poisson distribution and adjusted for the main risk factors and ambient meteorological variables. A mild prevalence (51.5%) of coronary artery disease (CAD) was registered in 6425 events. In GLM analysis, we observed an association among the pollutants with the coronary artery disease hospital admissions which was in the order of CO, NO₂, and PM₁₀. The highest association of each pollutant with hospital admission was observed as PM₁₀ at lag 4 (RR = 1.08; 95% CI 1.02, 1.14 and p < 0.05), NO₂ at lag 0 (RR = 1.22; 95% CI 1.00, 1.48), and CO at lag 0 (RR = 1.52 95% CI = (1.16, 1.99)). However, on dusty days, there were significantly higher numbers of referrals of cardiovascular patients (mean = 7.54 ± 4.44 and p = 0.002,) than on non-dusty days. According to these data, dust storms and some types of pollutants in the air are responsible for more admissions to hospitals for cardiovascular problems.
Afficher plus [+] Moins [-]Evaluation of the effects of low-impact development practices under different rainy types: case of Fuxing Island Park, Shanghai, China
2019
Wang, Hong-Wu | Zhai, Yue-Jiao | Wei, Yuan-Yuan | Mao, Yun-Feng
The soil permeability and underground water level greatly affect the performance of low-impact development (LID) practices. Shanghai is located in the area of estuary and is characterized by its high groundwater level and low soil infiltration rate. The LID practices in Fuxing Island Park, Shanghai, including a bioretention cell, swales, a permeable pavement, and a combined LID practices were studied in the present paper. The performance of LID practices during the period of eight rainfall events was evaluated in terms of hydrology and water quality. Due to the detention of the LID practices, a significant delay between the peak rainfall and the peak surface runoff was observed. On-site tests show it is suitable for the applicability of LID in a rainy city with low soil infiltration rate and high groundwater level. Moreover, the Stormwater Management Model (SWMM) was also used to compare the hydrologic effects before and after these four LID practices application in the park. Results indicated the LID practices could effectively reduce the runoff volume and the peak flow in the park. Furthermore, the runoff water quality evaluation showed the pollutants were effectively removed by these four LID practices due to both runoff treatment and flow volume reduction. The bioretention system proved to be effective as a result of its larger facility area while the swales had the obvious reduction volume both per facility area and per catchment area.
Afficher plus [+] Moins [-]Application of Fe-based metal-organic framework and its pyrolysis products for sulfonamide treatment
2019
Van Tran, Thuan | Nguyen, Duyen Thi Cam | Nguyen, Hong-Tham T. | Nanda, Sonil | N. Vo, Dai-Viet | Do, Sy Trung | Van Nguyen, Tuyen | Thi, Tuyet Anh Dang | Bach, Long Giang | Nguyen, Trinh Duy
The occurrence and fate of antibiotic compounds in water can adversely affect human and animal health; hence, the removal of such substrates from soil and water is indispensable. Herein, we described the synthesis method of mesoporous carbon (MPC) via the pyrolysis route from a coordination polymer Fe-based MIL-53 (or MIL-53, shortly). The MPC structure was analyzed by several physical techniques such as SEM, TEM, BET, FT–IR, VSM, and XRD. The response surface methodology (RSM) was applied to find out the effects of initial concentration, MPC dosage, and pH on the removal efficiency of trimethoprim (TMP) and sulfamethoxazole (SMX) antibiotics in water. Under the optimized conditions, the removal efficiencies of TMP and SMX were found to be 87% and 99%, respectively. Moreover, the adsorption kinetic and isotherm studies showed that chemisorption and the monolayer adsorption controlled the adsorption process. The leaching test and recyclability studies indicated that the MPC structure was stable and can be reused for at least four times without any considerable change in the removal efficiency. Plausible adsorption mechanisms were also addressed in this study. Because of high maximum adsorption capacity (85.5 mg/g and 131.6 mg/g for TMP and SMX, respectively) and efficient reusability, MPC is recommended to be a potential adsorbent for TMP and SMX from water media.
Afficher plus [+] Moins [-]Synthesis of rigid polyurethane foams from phosphorylated biopolyols
2019
de Haro, Juan Carlos | López-Pedrajas, Daniel | Pérez, Angel | Rodríguez, Juan Francisco | Carmona Rodríguez, Manuel
Renewable resources are playing a key role on the synthesis of biodegradable polyols. Moreover, the incorporation of covalently linked additives is increasing in importance in the polyurethane (PU) market. In this work, previously epoxidized grape seed oil and methyl oleate were transformed into phosphorylated biopolyols through an acid-catalyzed ring-opening hydrolysis in the presence of H₃PO₄. The formation of phosphate polyesters was confirmed by FT-IR and ³¹P-NMR. However, the synthesis of a high-quality PU rigid foam was not possible using exclusively these polyols attending to their low hydroxyl value. In that way, different rigid PU foams were prepared from the phosphorylated biopolyols and the commercial polyol Alcupol R4520. It was observed that phosphorylated biopolyols can be incorporated up to a 57 wt.% in the PU synthesis without significant structural changes with respect to the commercial foam. Finally, thermogravimetric and EDAX analyses revealed an improvement of thermal stability by the formation of a protective phosphorocarbonaceous char layer.
Afficher plus [+] Moins [-]Variations in cadmium accumulation and distribution among different oilseed rape cultivars in Chengdu Plain in China
2019
Wang, Xin | Bai, Jiuyuan | Wang, Jing | Le, Sixiu | Wang, Maolin | Zhao, Yun
Cadmium (Cd) is a widespread toxic heavy metal trace pollutant worldwide. The ability of Cd absorption and accumulation highly varies among different species and varieties. In order to screen oilseed rape cultivars which are appropriate for cultivation and application in Cd-contaminated soils, we conducted the field trial of 32 oilseed rape varieties in Shifang County of Chengdu Plain. The various biomass, Cd accumulation, and distribution patterns were investigated via determining the Cd concentration in different plant tissues. Moreover, the food safety risks of rapeseeds were finally assessed. The results indicated diverse responses to Cd stress appeared in various tested varieties, including plant biomass, seed yield, Cd concentration, and proportion in different tissues. And most Cd were concentrated in non-edible parts. Through cluster analysis, we found that Nanchongjie, Pengzhoubai, and J-25 belong to high-biomass and high-Cd-accumulated groups in experimental cultivars, which indicated that they could possess more biomass and gather higher Cd content in overground part, so they could be great materials for phytoremediation in Cd-polluted area. Besides, combined with the risk assessment of food safety in rapeseeds, cultivars 72A and 47 with the traits of high yield, low-Cd concentration, and low food safety risk can be considered as suitable materials to widely plant as cash crop. These results provide valuable reference for practical planting and application of oilseed rape in Cd-polluted areas.
Afficher plus [+] Moins [-]The effect of desert dust particles on rheological properties of saliva and mucus
2019
Penconek, Agata | Michalczuk, Urszula | Sienkiewicz, Agnieszka | Moskal, Arkadiusz
Transported desert dust particles (TDDP) are soil particles suspended in the air. Being spread all over the globe by the winds, TDDP affect animals, including humans, plants and other organisms not only in the areas of their emission. In humans, TDDP are responsible for diseases of the respiratory (e.g. asthma) and circulatory (e.g. heart failure) systems and they also act directly on the epithelium and its mucus layer after deposition in the mouth and respiratory system. The aim of the study was to determine the influence of TDDP on the rheology of mucus and saliva, and thus on their functioning. The artificial mucus and saliva, as well as Arizona TDDP, were used in experiments. The rheological properties of TDDP were determined with the use of an oscillatory rheometer, at various temperatures and in the presence of different amount of TDDP. Moreover, the diffusion time of the marker (rhodamine B) throughout mucus with desert dust particles was examined. The obtained results demonstrate that the presence of TDDP in the saliva and mucus model increases their apparent viscosity. The concentration of particles is positively correlated with the increase of viscosity. However, it has not been demonstrated that the presence of TDDP in mucus significantly influenced the diffusion of a fluorescent marker throughout the mucus. The presence of TDDP in the saliva and mucus may interfere with their moisturising function, and cause difficulties in swallowing by increasing the viscosity of mucus and saliva. Moreover, increased viscosity of mucus may cause problems with its ability to pass to the upper respiratory tracts, which may lead to a general discomfort or local inflammation.
Afficher plus [+] Moins [-]Biological and physiological responses of Perionyx excavatus to abamectin
2019
Ng, Beewah | Chanabun, Ratmanee | Somsak Panhā,
Biological and behavioral responses of the tropical earthworm Perionyx excavatus towards different concentrations of abamectin were evaluated. Abamectin significantly reduced the biomass and reproduction (cocoon production) of P. excavatus as well as inducing histopathological alterations in the cuticle. Biomass loss was recorded in P. excavatus exposed to abamectin at a concentration as low as 0.1 mg active ingredient (a.i.) kg⁻¹, while atrophy, another physiological response, was observed at an abamectin concentration of 0.21 μg cm⁻² in a filter paper test. Cocoon production was significantly reduced in the presence of abamectin, and no cocoons were produced at doses of 20 mg a.i. kg⁻¹ or higher, while abamectin at 50 mg a.i. kg⁻¹ induced extreme pathology, characterized by the loss of the integrity of the whole body wall and intestine of P. excavatus. Histopathological alterations can be used as a biomarker to evaluate the toxicological impact of exposure to abamectin.
Afficher plus [+] Moins [-]Can inorganic elements affect herpesvirus infections in European eels?
2019
Muñoz, Pilar | Barcala, Elena | Peñalver, José | Romero, Diego
In combination, pollution and pathogens represent a serious threat to the health of European eels that has been increasingly recognized. Thus, the impact of contaminants, cadmium, lead, mercury, and selenium, on anguillid herpesvirus 1 infection in wild European eels has been evaluated. Despite the small sample size, results indicate that selenium and mercury concentrations may compromise the European eel immune system as herpesvirus infection was more prevalent in specimens with higher Hg and Se hepatic concentrations.
Afficher plus [+] Moins [-]Graviola attenuates DMBA-induced breast cancer possibly through augmenting apoptosis and antioxidant pathway and downregulating estrogen receptors
2019
Zeweil, Mohamed M. | Sadek, Kadry M. | Taha, Nabil M. | El-Sayed, Yasser | Menshawy, Sherif
Breast cancer is a global public health problem where it is the second most prevalent cancer. Historical cancer treatment with graviola has been reported. This study aimed to investigate the protective effects of graviola on 7,12-dimethylbenz[a]anthracene (DMBA)–induced rat breast cancer. Fifty female Wistar rats were allocated into four groups: control group (gastro-gavaged by sesame oil), DMBA-treated group (gastro-gavaged a single dose of DMBA [50 mg/kg body mass, diluted in 1 ml sesame oil]) at the age 57 days, DMBA+G37-treated group (gastro-gavaged a single dose of DMBA [50 mg/kg body mass, diluted in 1 ml sesame oil]) at the age of 57 days plus graviola (200 mg/kg body mass) two times weekly (p.o.) at the age of 37 days till the end of the experiment, and DMBA+G57-treated group (received a single dose of DMBA [50 mg/kg body mass, diluted in 1 ml sesame oil]) plus graviola (200 mg/kg body mass) two times weekly at the age of 57 days until the end of the experiment. After the 30-week experimental period, blood samples were collected. Then, animals were sacrificed to determine the apoptotic indices, antioxidant status, and mammary gland tumor marker (CA 15-3). The DMBA upregulated the expression of one of the main anti-apoptotic genes: B-cell lymphoma protein 2 (BCL2) and estrogen receptor alpha (ER-α) gene. Moreover, it significantly increased breast lipid peroxidation and serum CA 15-3 but decreased breast antioxidant enzymatic activities (glutathione peroxidase, glutathione S-transferase, catalase, and superoxide dismutase). Nevertheless, administration of DMBA and graviola especially DMBA+G37 induced apoptosis through at least 1.5-fold in gene expression levels of pro-apoptotic genes: BCL2-associated X protein (BAX), tumor suppressor gene (P53), and cysteinyl-aspartic acid-protease-3 (caspase-3). A critical role of P53 in the regulation of the BCL2 and BAX has been reported. These proteins can determine if the cell undergoes apoptosis or cancels the process. Once the BAX gene activates caspase-3, there is no irreversible way toward cell death. Also, graviola ameliorated the DMBA effects on antioxidant enzymatic activities and tumor marker CA 15-3. This study concludes that graviola ameliorated DMBA-induced breast cancer potentially through upregulating apoptotic genes, downregulating the ER-α gene, increasing antioxidants, and decreasing lipid peroxidation levels.
Afficher plus [+] Moins [-]Impact of biochar-supported zerovalent iron nanocomposite on the anaerobic digestion of sewage sludge
2019
Zhang, Min | Li, Jianhua | Wang, Yuncai
Anaerobic digestion (AD) is an attractive technology for sludge treatment as it stabilizes sludge and produce renewable energy. However, problems such as low organic matter content and high heavy metals level are often encountered which severely limits the effectiveness of AD. In this study, the biochar-supported nanoscale zerovalent iron (nZVI-BC) was synthesized and used as additives during AD of sewage sludge to investigate the enhancement effects for methane production and its impacts on microbial structure at mesophilic temperature. nZVI-BC addition enhanced process stability by improving the generation and degradation of intermediate organic acids, but inhibitory effects were observed at high dosage. The methane content and cumulative methane yields were increased by 29.56% and 115.39%, respectively. Compared with AD without nZVI-BC, the application of nZVI-BC showed positive effect on improvement of metals (Cu, Cd, Ni, Cr, and Zn) stabilization in the digestate. Microbial community analysis illustrated that nZVI-BC addition could significantly increase the Shannon diversity index and Chao1 richness index of archaea, and meanwhile archaea were more diverse in nZVI-BC amended digesters than in control. It was notable that Methanosaeta dominated in all the digesters at genera level, while the relative abundance of hydrogenotrophic methanogens (Methanobacterium and methanospirillum) increased 35.39% in nZVI-BC amended digesters compared to the control, resulting in higher methane production. The results will guide development of microbial management methods to enhance the stability of AD process.
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