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Multi-generational impacts of organic contaminated stream water on Daphnia magna: A combined proteomics, epigenetics and ecotoxicity approach 全文
2019
Chatterjee, Nivedita | Choi, Suhyon | Kwon, Oh Kwang | Lee, Sangkyu | Choi, Jinhee
The present study aimed to elucidate the mechanisms of organismal sensitivity and/or physiological adaptation in the contaminated water environment. Multigenerational cultures (F0, F1, F2) of Daphnia magna in collected stream water (OCSW), contaminated with high fecal coliform, altered the reproductive scenario (changes in first brood size timing, clutch numbers, clutch size etc.), compromised fitness (increase hemoglobin, alteration in behavior), and affected global DNA methylation (hypermethylation) without affecting survival. Using proteomics approach, we found 288 proteins in F0 and 139 proteins in F2 that were significantly differentially upregulated after OCSW exposure. The individual protein expressions, biological processes and molecular functions were mainly related to metabolic processes, development and reproduction, transport (protein/lipid/oxygen), antioxidant activity, increased globin and S-adenosylmethionine synthase protein level etc., which was further found to be connected to phenotype-dependent endpoints. The proteomics pathway analysis evoked proteasome, chaperone family proteins, neuronal disease pathways (such as, Parkinson's disease) and apoptosis signaling pathways in OCSW-F0, which might be the cause of behavioral and developmental alterations in OCSW-F0. Finally, chronic multigenerational exposure to OCSW exhibited slow physiological adaptation in most of the measured effects, including proteomics analysis, from the F0 to F2 generations. The common upregulated proteins in both generations (F0 & F2), such as, globin, vitellinogen, lipid transport proteins etc., were possibly play the pivotal role in the organism's physiological adaptation. Taken together, our results, obtained with a multilevel approach, provide new insight of the molecular mechanism in fecal coliform-induced phenotypic plasticity in Daphnia magna.
显示更多 [+] 显示较少 [-]Consistent microplastic ingestion by deep-sea invertebrates over the last four decades (1976–2015), a study from the North East Atlantic 全文
2019
Courtene-Jones, Winnie | Quinn, Brian | Ewins, Ciaran | Gary, Stefan F. | Narayanaswamy, Bhavani E.
Although evidence suggests the ubiquity of microplastics in the marine environment, our knowledge of its occurrence within remote habitats, such as the deep sea, is scarce. Furthermore, long term investigations of microplastic abundances are even more limited. Here we present a long-term study of the ingestion of microplastics by two deep-sea benthic invertebrates (Ophiomusium lymani and Hymenaster pellucidus) sampled over four decades. Specimens were collected between the years 1976–2015 from a repeat monitoring site >2000 m deep in the Rockall Trough, North East Atlantic. Microplastics were identified at a relatively consistent level throughout and therefore may have been present at this locality prior to 1976. Considering the mass production of plastics began in the 1940s - 50s our data suggest the relatively rapid occurrence of microplastics within the deep sea. Of the individuals examined (n = 153), 45% had ingested microplastics, of which fibres were most prevalent (95%). A total of eight different polymer types were isolated; polyamide and polyester were found in the highest concentrations and in the majority of years, while low-density polystyrene was only identified in 2015. This study provides an assessment of the historic occurrence of microplastics on the deep seafloor and presents a detailed quantification and characterisation of microplastics ingested by benthic species. Furthermore these data advance our knowledge on the long-term fate of microplastic in marine systems.
显示更多 [+] 显示较少 [-]Individual exposure level following indoor and outdoor air pollution exposure in Dakar (Senegal) 全文
2019
Individual exposure level following indoor and outdoor air pollution exposure in Dakar (Senegal) 全文
2019
The consequences of indoor and outdoor air pollution on human health are of great concern nowadays. In this study, we firstly evaluated indoor and outdoor air pollution levels (CO, CO₂, NO, NO₂, PM₁₀) at an urban site in Dakar city center and at a rural site. Then, the individual exposure levels to selected pollutants and the variations in the levels of biomarkers of exposure were investigated in different groups of persons (bus drivers, traders working along the main roads and housemaids). Benzene exposure levels were higher for housemaids than for bus drivers and traders. High indoor exposure to benzene is probably due to cooking habits (cooking with charcoal), local practices (burning of incense), the use of cleaning products or solvent products which are important emitters of this compound. These results are confirmed by the values of S-PMA, which were higher in housemaids group compared to the others. Urinary 1-HOP levels were significantly higher for urban site housemaids compared to semirural district ones.Moreover, urinary levels of DNA oxidative stress damage (8-OHdG) and inflammatory (interleukin-6 and -8) biomarkers were higher in urban subjects in comparison to rural ones.The air quality measurement campaign showed that the bus interior was more polluted with PM₁₀, CO, CO₂ and NO than the market and urban or rural households. However, the interior of households showed higher concentration of VOCs than outdoor sites confirming previous observations of higher indoor individual exposure level to specific classes of pollutants.
显示更多 [+] 显示较少 [-]Individual exposure level following indoor and outdoor air pollution exposure in Dakar (Senegal)
Non-covalent assembled laccase-graphene composite: Property, stability and performance in beta-blocker removal 全文
2019
Immobilization of enzymes on carriers have been pursued to make the enzyme stable, reusable and obtaining even better enzyme activity. Due to the highly stable two-dimensional layer structure, large surface area and pore volume, graphene materials were seemed as ideal carrier for enzyme immobilization. In this paper, pristine few layer graphene (FLG) was applied to interact with laccase to synthesize laccase-graphene composite and the results of AFM, FT-IR and adsorption isotherm suggested that laccase was loaded on the FLG with a very high loading dosage (221.1 mg g⁻¹). Based on the measured interaction force and binding type between laccase and graphene, we proposed that the great enzyme loading on FLG is likely due to the non-covalent π-π stacking in addition to the large surface area of FLG. The composite has better stability to the variance of pH and storage temperature than free laccase. The synthesized composite can effectively transform beta-blocker labetalol with an enhanced efficiency, though the possible reaction pathways kept not changing. We further performed molecular simulation study on the crystal structure variation of laccase binding on FLG and proposed that catalytic activity enhancement may be attributed to the more exposure extent of the catalytic center of laccase. In addition, the laccase-graphene composite can be reused more than ten times in catalyzing the labetalol removal.
显示更多 [+] 显示较少 [-]Impacts of air pollution on dry eye disease among residents in Hangzhou, China: A case-crossover study 全文
2019
Mo, Zhe | Fu, Qiuli | Lyu, Danni | Zhang, Lifang | Qin, Zhenwei | Tang, Qiaomei | Yin, Houfa | Xu, Peiwei | Wu, Lizhi | Wang, Xiaofeng | Lou, Xiaoming | Chen, Zhijian | Yao, Ke
The purpose of this study is to investigate the potential associations between air pollution and dry eye disease (DED). Data of outdoor air pollutants and meteorology as well as outpatient visits for DED were collected. A time-stratified case-crossover approach was used to analyze the associations between ambient air pollutants and outpatient visits for DED. Among the 5062 DED patients studied, 65.45% were female and 34.55% were male. In the single-pollutant model, significant associations were observed between an increase of 10 μg/m³ in the concentrations of fine-particulate matter with a median aerometric diameter of less than 10 μm (PM₁₀), fine-particulate matter with a median aerometric diameter of less than 2.5 μm (PM₂.₅), sulfur dioxide (SO₂), nitrogen dioxide (NO₂), and carbon monoxide (CO) and outpatient visits for DED. These results were consistent with those of the multipollutant model. The strongest associations between air pollutants and patient visits were observed during the cold season and in patients aged 21–40. The significant association between air pollutants (PM₁₀, PM₂.₅, SO₂, NO₂, and CO) and DED outpatient visits indicates the importance of increased environmental protection.
显示更多 [+] 显示较少 [-]Microfiber release from different fabrics during washing 全文
2019
Yang, Libiao | Qiao, Fei | Lei, Kun | Li, Huiqin | Kang, Yu | Cui, Song | An, Lihui
Microfiber is a subgroup of microplastics and accounts for a large proportion of microplastics in aquatic environment, especially in municipal effluents. The purpose of the present study was to quantify microfiber shedding from three most populate synthetic textile fabrics: polyester, polyamide, and acetate fabrics. The results showed that more microfibers were released after washing with a pulsator laundry machine than a platen laundry machine. The greatest number of microfibers was released from acetate fabric, which was up to 74,816 ± 10,656 microfibers/m2 per wash, although microfibers were shed from all materials. Moreover, an increasing trend was found in the number of microfibers shedding from synthetic fabrics with the washing temperature increasing, and greater microfiber release occurred when washing fabrics with detergent rather than with water alone. The lint filter bag equipped with the pulsator laundry machine retained the longer microfibers (>1000 μm), but not the shorter microfibers (<500 μm) instead of releasing into the drainage system. Our data suggested that microfibers released during washing of synthetic fabrics may be an important source of microfibers in aquatic environment due to the increasing production and use of synthetic fabrics globally. Thus, more efficient filtering bags or other technologies in household washing machines should be developed to prevent and reduce the release of microfibers from domestic washing.
显示更多 [+] 显示较少 [-]Genotoxicological analyses of insectivorous bats (Mammalia: Chiroptera) in central Brazil: The oral epithelium as an indicator of environmental quality 全文
2019
Benvindo-Souza, Marcelino | Borges, Rinneu Elias | Pacheco, Susi Missel | Santos, Lia Raquel de Souza
The micronucleus (MN) test of the human buccal mucosa was developed more than 30 years ago, although this technique has only recently been applied to wild mammals. This paper presents a pioneering study in the genotoxicological evaluation of the exfoliated cells of the buccal mucosa of bats. The assay was applied to two insectivorous bat species (Noctilio albiventris and Pteronotus parnellii) sampled in riparian corridors located in the city of Palmas (capital of the Brazilian state of Tocantins), with the results being compared with those obtained for a third insectivorous species (Nyctinomops laticaudatus), which has established a colony under a road bridge in the same region. This colony represents one of the largest molossidae populations ever recorded in Brazil. A significantly higher frequency of micronuclei was recorded in this colony, as well as a number of other nuclear abnormalities, including binucleated cells, cells with condensed chromatin and karyolysis, in comparison with the bats from the riparian corridors, indicating that the bats from the bridge colony are more susceptible to genotoxic damage. Thus, it is demonstrated the importance of the biomarker (MN) for use in wild animals and allows to conclude that colony bats are more susceptible to genotoxic damages.
显示更多 [+] 显示较少 [-]Trace metals in polyethylene debris from the North Atlantic subtropical gyre 全文
2019
Prunier, Jonathan | Maurice, Laurence | Perez, Emile | Gigault, Julien | Pierson Wickmann, Anne-Catherine | Davranche, Mélanie | Halle, Alexandra ter
Plastic pollution in the marine environment poses threats to wildlife and habitats through varied mechanisms, among which are the transport and transfer to the food web of hazardous substances. Still, very little is known about the metal content of plastic debris and about sorption/desorption processes, especially with respect to weathering. In this study, plastic debris collected from the North Atlantic subtropical gyre was analyzed for trace metals; as a comparison, new packaging materials were also analyzed. Both the new items and plastic debris showed very scattered concentrations. The new items contained significant amounts of trace metals introduced as additives, but globally, metal concentrations were higher in the plastic debris. The results provide evidence that enhanced metal concentrations increase with the plastic state of oxidation for some elements, such as As, Ti, Ni, and Cd. Transmission electron microscopy showed the presence of mineral particles on the surface of the plastic debris. This work demonstrates that marine plastic debris carries complex mixtures of heavy metals. Such materials not only behave as a source of metals resulting from intrinsic plastic additives but also are able to concentrate metals from ocean water as mineral nanoparticles or adsorbed species.
显示更多 [+] 显示较少 [-]Supported-liquid phase extraction in combination with isotope-dilution gas chromatography triple quadrupole tandem mass spectrometry for high-throughput quantitative analysis of polycyclic aromatic hydrocarbon metabolites in urine 全文
2019
Jiang, Jie | Ip, Ho Sai Simon | Zhou, Junqiang | Guan, Yufeng | Zhang, Jianqing | Liu, Guihua | Garrotto, Natalia | Lu, Yifu | DeGuzman, Josephine | She, Jianwen
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental contaminants with a number of them being carcinogenic. One of the approaches to assess human exposure to PAHs is to measure their urinary metabolites, monohydroxyl polycyclic aromatic hydrocarbons (OH-PAHs), with a method allowing for high throughput and short turn-around time. We developed a method to quantify nine urinary OH-PAHs by using supported liquid phase extraction (SLE) and isotope dilution gas chromatography tandem mass spectrometry (GC-MS/MS). SLE demonstrated advantages over the traditionally used liquid-liquid extraction techniques. The target analytes with spiked deuterated and ¹³C-labeled internal standards were extracted from urine by SLE after enzymatic cleavage of the glucuronide and sulfate conjugates. The extracted analytes were then derivatized with N-Methyl-N-(trimethylsilyl) trifluoroacetamide (MSTFA), and analyzed by GC-MS/MS. Six solvent mixtures were evaluated as the SLE extraction solvent, and pentane:chloroform (7:3, v/v) was selected due to its best overall analytical performance. Method detection limits for the 9 analytes ranged from 2.3 to 13.8 pg/mL. Precision and accuracy were satisfactory. SLE and internal isotope labeled standard combination reduced matrix effect effectively. This new method using SLE sample preparation techniques coupled with GC-MS/MS proves applicable to urinary measurements for PAH exposure studies for general population.
显示更多 [+] 显示较少 [-]Distribution and potential health impacts of microplastics and microrubbers in air and street dusts from Asaluyeh County, Iran 全文
2019
Abbasi, Sajjad | Keshavarzi, Behnam | Moore, Farid | Turner, Andrew | Kelly, Frank J. | Dominguez, Ana Oliete | Jaafarzadeh, Neemat
While the distribution and effects of microplastics (MPs) have been extensively studied in aquatic systems, there exits little information on their occurrence in the terrestrial environment and their potential impacts on human health. In the present study, street dust and suspended dust were collected from the city and county of Asaluyeh, Iran. Samples were characterized by various microscopic techniques (fluorescence, polarized light, SEM) in order to quantify and classify MPs and microrubbers (MRs) in the urban and industrial environments that are potentially ingestible or inhalable by humans. In < 5-mm street dust retrieved from 15 sites, there were an average of 900 MPs and 250 MRs per 15 g of sample, with MPs exhibiting a range of colours and sizes (<100 to >1000 μm). Most street dust samples were dominated by spherical and film-like particles and MRs largely made up of different sizes of black fragments and fibrous particulates. Airborne dust collected daily over an eight-day period at two locations revealed the ubiquity of fibrous MPs of sizes ranging from about 2 μm to 100 μm and an abundance of about 1 per m⁻³. These samples contained small MR fragments whose precise characteristics were more difficult to define. Based on the median concentrations in street dust, estimates of acute exposure through ingestion are about 5 and 15 MP d⁻¹ and 2 and 7 MR d⁻¹ for construction workers and young children, respectively. Quantities of inhalable particulates were more difficult to define but the potential toxicity of MPs and MRs taken in by this route was evaluated from assays performed using particulates isolated from street dusts in the presence of an artificial lung fluid. Both types of particle exhibited oxidative potential, with MPs displaying consumptions of different antioxidants that were comparable with corresponding values for a reference urban particulate dust but lower than those for London ambient particulate matter. Thus, MPs and MRs contribute towards the health impacts of urban and industrial dusts but their precise roles remain unclear and warrant further study.
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