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Sodium fluoride exposure triggered the formation of neutrophil extracellular traps 全文
2020
Wang, Jing-Jing | Wei, Zheng-Kai | Han, Zhen | Liu, Zi-Yi | Zhang, Yong | Zhu, Xing-Yi | Li, Xiao-Wen | Wang, Kai | Yang, Zheng-Tao
In recent years, numerous studies paid more attention to the molecular mechanisms associated with fluoride toxicity. However, the detailed mechanisms of fluoride immunotoxicity in bovine neutrophils remain unclear. Neutrophil extracellular traps (NETs) is a novel immune mechanism of neutrophils. We hypothesized that sodium fluoride (NaF) can trigger NETs activation and release, and investigate the related molecular mechanisms during the process. We exposed peripheral blood neutrophils to 1 mM NaF for 120 min in bovine neutrophils. The results showed that NaF exposure triggered NET-like structures decorated with histones and granule proteins. Quantitative measurement of NETs content correlated positively with the concentration of NaF. Mechanistically, NaF exposure increased reactive oxygen species (ROS) levels and phosphorylation levels of ERK, p38, whereas inhibiting the activities of superoxide dismutase (SOD) and catalase (CAT) compared with control neutrophils. NETs formation is induced by NaF and this effect was inhibited by the inhibitors diphenyleneiodonium chloride (DPI), U0126 and SB202190. Our findings described the potential importance of NaF-triggered NETs related molecules, which might help to extend the current understanding of NaF immunotoxicity.
显示更多 [+] 显示较少 [-]Impacts of different sources of animal manures on dissemination of human pathogenic bacteria in agricultural soils 全文
2020
Li, Jinyang | Chen, Qinglin | Li, Helian | Li, Shiwei | Liu, Yinghao | Yang, Liyuan | Han, Xuemei
The human pathogenic bacteria (HPB) in animal feces may disseminate to agricultural soils with their land application as organic fertilizer. However, the knowledge about the impacts of different sources and rates of animal manures on the temporal changes of soil HPB remains limited, which hamper our ability to estimate the potential risks of their land application. Here, we constructed an HPB database including 565 bacterial strains. By blasting the 16 S rRNA gene sequences against the database we explored the occurrence and fate of HPB in soil microcosms treated with two rates of swine, poultry or cattle manures. A total of 30 HPB were detected in all of manure and soil samples. Poultry manure at the high level obviously improved the abundance of soil HPB. The application of swine manure could introduce concomitant HPB into the soils. Of which, Pseudomonas syringae pv. syringae B728a and Escherichia coli APEC O78 may deserve more attention because of their survival for a few days in manured soils and being possible hosts of diverse antibiotic resistance genes (ARGs) as revealed by co-occurrence pattern. Bayesian source tracking analysis showed that the HPB derived from swine manure had a higher contribution to soil pathogenic communities than those from poultry or cattle manures in early days of incubation. Mantel test together with variation partitioning analysis suggested that bacterial community and soil physicochemical properties were the dominant factors determining the profile of HPB and contributed 64.7% of the total variations. Overall, our results provided experimental evidence that application of animal manures could facilitate the potential dissemination of HPB in soil environment, which should arouse sufficient attention in agriculture practice and management to avoid the threat to human health.
显示更多 [+] 显示较少 [-]Internal distribution and fate of persistent organic contaminants (PCDD/Fs, DL-PCBs, HBCDs, TBBPA, and PFASs) in a Bos Taurus 全文
2020
Shin, Eun-su | Jeong, Yuna | Barghi, Mandana | Seo, Sung-Hee | Kwon, Sae Yun | Chang, Yoon Seok
While terrestrial organisms such as livestock are consumed regularly, studies of internal distribution and bioaccumulation of persistent organic pollutants (POPs) have been focused more on aquatic organisms. In this study, we have assessed the internal distribution and fate of legacy (PCDD/Fs and PCBs) and emerging POPs (HBCDs and PFASs), and TBBPA in 42 tissues of a Bos Taurus. PCDD/Fs, DL-PCBs, and HBCDs were found 3, 4, and 4-fold higher in the lipid-rich organs (subcutaneous fat, visceral fat, large intestine) compared to the remaining organs and muscles, owing to their hydrophobic properties. The TBBPA concentration in the excrement was 36-fold higher compared to the average tissues, suggesting a short internal half-life of TBBPA. Among PFASs, PFUnDA displayed 98% contribution from all ionic PFASs in the tissues due to its strong binding affinity, high exposure via feed and water, and increasing emergence of PFUnDA and its precursors in the Southeast Asian countries. While our study suggests that, at the moment, there is no significant health risks to the general Korean population, the future changes in environmental exposure as well as the internal dynamics and fate of various POPs species should be kept in mind when consuming various parts of livestock.
显示更多 [+] 显示较少 [-]Oxidative stress and respiratory symptoms due to human exposure to polycyclic aromatic hydrocarbons (PAHs) in Kumasi, Ghana 全文
2017
Bortey-Sam, Nesta | Ikenaka, Yoshinori | Akoto, Osei | Nakayama, Shouta M.M. | Asante, Kwadwo A. | Baidoo, Elvis | Obirikorang, Christian | Saengtienchai, Aksorn | Isoda, Norikazu | Nimako, Collins | Mizukawa, Hazuki | Ishizuka, Mayumi
Studies of polycyclic aromatic hydrocarbons (PAHs) and its metabolites in PM10, soils, rat livers and cattle urine in Kumasi, Ghana, revealed high concentrations and cancer potency. In addition, WHO and IARC have reported an increase in cancer incidence and respiratory diseases in Ghana. Human urine were therefore collected from urban and control sites to: assess the health effects associated with PAHs exposure using malondialdehyde (MDA) and 8-hydroxy-2-deoxyguanosine (8-OHdG); identify any association between OH-PAHs, MDA, 8-OHdG with age and sex; and determine the relationship between PAHs exposure and occurrence of respiratory diseases. From the results, urinary concentrations of the sum of OH-PAHs (∑OHPAHs) were significantly higher from urban sites compared to the control site. Geometric mean concentrations adjusted by specific gravity, GMSG, indicated 2-OHNaphthalene (2-OHNap) (6.01 ± 4.21 ng/mL) as the most abundant OH-PAH, and exposure could be through the use of naphthalene-containing-mothballs in drinking water purification, insect repellent, freshener in clothes and/or “treatment of various ailments”. The study revealed that exposure to naphthalene significantly increases the occurrence of persistent cough (OR = 2.68, CI: 1.43–5.05), persistent headache (OR = 1.82, CI: 1.02–3.26), tachycardia (OR = 3.36, CI: 1.39–8.10) and dyspnea (OR = 3.07, CI: 1.27–7.43) in Kumasi residents. Highest level of urinary 2-OHNap (224 ng/mL) was detected in a female, who reported symptoms of persistent cough, headache, tachycardia, nasal congestion and inflammation, all of which are symptoms of naphthalene exposure according to USEPA. The ∑OHPAHs, 2-OHNap, 2-3-OHFluorenes, and -OHPhenanthrenes showed a significantly positive correlation with MDA and 4-OHPhenanthrene with 8-OHdG, indicating possible lipid peroxidation/cell damage or degenerative disease in some participants. MDA and 8-OHdG were highest in age group 21–60. The present study showed a significant sex difference with higher levels of urinary OH-PAHs in females than males.
显示更多 [+] 显示较少 [-]Health conditions in rural areas with high livestock density: Analysis of seven consecutive years 全文
2017
van Dijk, Christel E. | Zock, Jan-Paul | Baliatsas, Christos | Smit, Lidwien A.M. | Borlée, Floor | Spreeuwenberg, Peter | Heederik, Dick | Yzermans, C Joris
Previous studies investigating health conditions of individuals living near livestock farms generally assessed short time windows. We aimed to take time-specific differences into account and to compare the prevalence of various health conditions over seven consecutive years. The sample consisted of 156,690 individuals registered in 33 general practices in a (rural) area with a high livestock density and 101,015 patients from 23 practices in other (control) areas in the Netherlands. Prevalence of health conditions were assessed using 2007–2013 electronic health record (EHR) data. Two methods were employed to assess exposure: 1) Comparisons between the study and control areas in relation to health problems, 2) Use of individual estimates of livestock exposure (in the study area) based on Geographic Information System (GIS) data. A higher prevalence of chronic bronchitis/bronchiectasis, lower respiratory tract infections and vertiginous syndrome and lower prevalence of respiratory symptoms and emphysema/COPD was found in the study area compared with the control area. A shorter distance to the nearest farm was associated with a lower prevalence of upper respiratory tract infections, respiratory symptoms, asthma, COPD/emphysema, allergic rhinitis, depression, eczema, vertiginous syndrome, dizziness and gastrointestinal infections. Especially exposure to cattle was associated with less health conditions. Living within 500m of mink farms was associated with increased chronic enteritis/ulcerative colitis. Livestock-related exposures did not seem to be an environmental risk factor for the occurrence of health conditions. Nevertheless, lower respiratory tract infections, chronic bronchitis and vertiginous syndrome were more common in the area with a high livestock density. The association between exposure to minks and chronic enteritis/ulcerative colitis remains to be elucidated.
显示更多 [+] 显示较少 [-]Metal exposure in cows grazing pasture contaminated by iron industry: Insights from magnetic particles used as tracers 全文
2016
Ayrault, Sophie | Catinon, Mickaël | Boudouma, Omar | Bordier, Louise | Agnello, Gregory | Reynaud, Stéphane | Tissut, Michel
Magnetic particles (MP) emitted by an iron smelter were used to investigate the exposure of cows grazing on a grassland polluted by these MP and by large amounts of potentially toxic elements (PTE). The morphology as well as the chemical composition of the MP separated from cow dung were studied. Large amounts of typical MP were found (1.1 g kg−1 dry weight) in the cow dung sampled from the exposed site, whereas these particles were absent from the reference unpolluted site. The ingested MP were mainly technogenic magnetic particles (TMP) emitted by the smelter. Considering the MP concentration in the grazed grass on the exposed site, it was concluded that cows absorb the MP not only from the grass but also from the soil surface. The results of a mild acidic leaching of the MP suggested that the particles were possibly submitted to a superficial dissolution in the abomasum, pointing at a potential route of transfer of the PTE originating from the TMP and leading into food chains. TMP were only a small part of the anthropogenic contamination having affected the soil and the dung. However, due to their unequivocal signature, TMP are a powerful tracer of the distribution of PTE in the different compartments constituting the food chains and the ecosystems. Furthermore, the measurement of the particle sizes gave evidence that a noticeable proportion of the MP could enter the respiratory tract.
显示更多 [+] 显示较少 [-]Predicting fecal indicator organism contamination in Oregon coastal streams 全文
2015
Pettus, Paul | Foster, Eugene | Pan, Yangdong
In this study, we used publicly available GIS layers and statistical tree-based modeling (CART and Random Forest) to predict pathogen indicator counts at a regional scale using 88 spatially explicit landscape predictors and 6657 samples from non-estuarine streams in the Oregon Coast Range. A total of 532 frequently sampled sites were parsed down to 93 pathogen sampling sites to control for spatial and temporal biases. This model's 56.5% explanation of variance, was comparable to other regional models, while still including a large number of variables. Analysis showed the most important predictors on bacteria counts to be: forest and natural riparian zones, cattle related activities, and urban land uses. This research confirmed linkages to anthropogenic activities, with the research prediction mapping showing increased bacteria counts in agricultural and urban land use areas and lower counts with more natural riparian conditions.
显示更多 [+] 显示较少 [-]Occurrence of ectoparasiticides in Australian beef cattle feedlot wastes 全文
2013
A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the simultaneous analysis of 6 ectoparasiticides – 2 synthetic pyrethroids (deltamethrin, cypermethrin) and 4 macrocyclic lactones (abamectin, doramectin, ivermectin and eprinomectin) in biosolids. The method was used to investigate the occurrence of these ectoparasiticides in beef cattle feedlot wastes in Australia from 5 commercial feedlot operations which employ varying waste management practices. Deltamethrin and cypermethrin were not detected in any of the samples while abamectin, ivermectin, doramectin and eprinomectin were detected in some of the samples with concentrations ranging from 1 to 36 μg/kg dry weight (d.w.) freeze dried feedlot waste. Levels of macrocyclic lactones detected in the feedlot wastes varied and were dependent on sample type. The effect of seasonal variations and waste management practices were also investigated in this study.
显示更多 [+] 显示较少 [-]Blood Pb and δ-ALAD inhibition in cattle and sheep from a Pb-polluted mining area 全文
2012
Rodríguez-Estival, Jaime | Barasona, José A. | Mateo, Rafael
The effects of Pb pollution on cattle and sheep raised in an ancient mining area were studied through the use of blood Pb (PbB) levels and δ-aminolevulinic acid dehydratase (δ-ALAD) activity. Lead levels in livestock blood from the mining area (n=110) were significantly elevated when compared to the controls (n=79). In 91.4% of cattle (n=58) and 13.5% of sheep (n=52) sampled in the mining area, PbB levels corresponded to subclinical exposure (6–35μg/dl). Two young cattle (<2 years) from the mining area (n=5) had PbB levels indicative of clinical poisoning (>35μg/dl). Elevated PbB was also accompanied by δ-ALAD activity inhibition in blood, which confirms that measurable effects of Pb poisoning were taking place. Observed PbB levels suggest that a potential risk to human consumers of beef from the Pb polluted areas may also exist, as has been shown previously for game meat from the same mining area.
显示更多 [+] 显示较少 [-]Mobility of radium and trace metals in sediments of the Winterbeek: Application of sequential extraction and DGT techniques 全文
2010
Gao, Y. | Baeyens, W. | Galan, S De | Poffijn, A. | Leermakers, M.
For several decades, phosphate ores containing 226Ra as well as several trace metals have been processed in Belgium to produce calcium phosphate for use in cattle food. The waste water is discharged in two small rivers, the Laak and the Winterbeek. In this study, the levels of 226Ra and trace metals in surface water and sediments of the Winterbeek were investigated and the mobility of these compounds was assessed using DGT (Diffusive Gradient in Thin Films) and sequential extraction techniques. The concentrations of 226Ra and trace metals in water and sediment indicate a decreasing trend in inputs to the Winterbeek. The mobility of 226Ra, assessed by DGT, is related to the reductive mobilization of Fe. The sequential extraction technique shows that at some stations an important fraction of 226Ra is found to labile sediment phases. Diffusive 226Ra sediment fluxes, are however, relatively small and have only a minor contribution to the water column concentration of 226Ra.
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