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Use of nondestructive biomarkers and residue analysis to assess the health status of endangered species of pinnipeds in the south-west Atlantic.
1997
Fossi M.C. | Marsili L. | Junin M. | Castello H. | Lorenzani J.A. | Casini S. | Savelli C. | Leonzio C.
A closer look on the variety and abundance of the faecal resistome of wild boar
2022
Dias, Diana | Fonseca, Carlos | Mendo, Sónia | Caetano, Tânia
Antimicrobial resistance (AMR) is a serious problem for public and animal health, and also for the environment. Monitoring and reporting the occurrence of AMR determinants and bacteria with the potential to disseminate is a priority for health surveillance programs around the world and critical to the One Health concept. Wildlife is a reservoir of AMR, and human activities can strongly influence their resistome.The main goal of this work was to study the resistome of wild boar faecal microbiome, one of the most important game species in Europe using metagenomic and culturing approaches. The most abundant genes identified by the high-throughput qPCR array encode mobile genetic elements, including integrons, which can promote the dissemination of AMR determinants. A diverse set of genes (n = 62) conferring resistance to several classes of antibiotics (ARGs), some of them included in the WHO list of critically important antimicrobials were also detected. The most abundant ARGs confer resistance to tetracyclines and aminoglycosides. The phenotypic resistance of E. coli and Enterococcus spp. were also investigated, and together supported the metagenomic results.As the wild boar is an omnivorous animal, it can be a disseminator of AMR bacteria and ARGs to livestock, humans, and the environment. This study supports that wild boar can be a key sentinel species in ecosystems surveillance and should be included in National Action Plans to fight AMR, adopting a One Health approach.
Показать больше [+] Меньше [-]First report on the presence of small microplastics (≤ 3 μm) in tissue of the commercial fish Serranus scriba (Linnaeus. 1758) from Tunisian coasts and associated cellular alterations
2020
Zitouni, Nesrine | Bousserrhine, Noureddine | Belbekhouche, Sabrina | Missawi, Omayma | Alphonse, Vanessa | Boughatass, Iteb | Banni, Mohamed
There is limited research on the ingestion of microplastic particles (MPs) by fish from the southern part of the Mediterranean Sea. This study provides the occurrence of small MPs (≤3 μm) in the gastrointestinal tract and muscle of adult benthopelagic fish Serranus scriba (L.1758), caught along Tunisian coasts. MPs were extracted from selected tissues using a potassium hydroxide digestion method (KOH 10%) and then quantified, and their chemical structure was characterized through Raman microspectroscopy. The results highlighted that MPs were present in all samples. The average abundance of MPs per gram of fish tissue identified through successive filters of 3 μm, 1.2 μm, and 0.45 μm differed significantly among the sites. The properties of the MPs extracted indicated that polyethylene-vinyl-acetate (PEVA: 33.45%), high density polyethylene (HD-PE: 17.33%), and fragments were the most abundant plastic types and shape found, respectively. Among those, most MPs were found at a size class of 3–1.2 μm (∼60%), especially in the muscle, suggesting a high transfer of MPs into the human diet. Our field work also aimed to explore the effects observed in the gastrointestinal tract with a battery of biomarkers assessing oxidative stress and neurotoxicity. The preliminary results of this study showed the existence of a link between small MPs, sites, and their associated urban activities and induced oxidative stress. However, more detailed studies are required to evaluate the transfer of MPs into tissues and the potential impacts of this transfer on human health.
Показать больше [+] Меньше [-]Fumonisins B1 exposure triggers intestinal tract injury via activating nuclear xenobiotic receptors and attracting inflammation response
2020
Li, Xinran | Cao, Changyu | Zhu, Xingyi | Li, Xiaowen | Wang, Kai
Fumonisins (FBs) are mycotoxins that are widely distributed in crops and feed, and ingestion of FBs -contaminated crops is harmful to animal health. Furthermore, it is unknown if Fumonisins B1 (FB1) can cause intestinal toxicity. To investigate FB1-induced intestinal toxicity, mice were treated with 0 or 5 mg/kg FB1 by gavage administration for 42 days. Histopathology indicated that FB1 exposure caused proliferation of intestinal epithelial cells, intestinal villi and epithelial layer shedding, intestinal gland atrophy, and necrosis. Notably, FB1 interfered with nuclear xenobiotic receptors (NXR) homeostasis by regulating the level of aryl hydrocarbon receptor (AHR), constitutive androstane receptor (CAR), pregnane X receptor (PXR) and downstream target genes (CYP450s). Moreover, abnormal expression of inflammatory cytokines (IL-1β, IL-2, IL-4, IL-10, and TNF-α) indicated the occurrence of inflammation. The present study provides new insights regarding the mechanism of FB1-induced intestinal toxicity through activating the NXR system and by triggering inflammatory responses in the intestinal tract in mice.
Показать больше [+] Меньше [-]Dibutyl phthalate contamination accelerates the uptake and metabolism of sugars by microbes in black soil
2020
Chen, Wenjing | Wang, Zhigang | Xu, Weihui | Tian, Renmao | Zeng, Jin
Dibutyl phthalate (DBP) is widely used as plasticizer and has been detected in the environment, posing a threat to animal health. However, the effects of DBP on agricultural microbiomes are not known. In this study, DBP levels in black soil were evaluated, and the impact of DBP contamination on the uptake and metabolism of sugars in microbes was assessed by glucose absorption tests, metaproteomics, metabolomics, enzyme activity assays and computational simulation analysis. The results indicated that DBP contamination accelerated glucose consumption and upregulated the expression of porins and periplasmic monosaccharide ATP-binding cassette (ABC) transporter solute-binding proteins (SBPs). DBP and its metabolic intermediates (carboxymuconate and butanol) may form a stable complex with sugar transporters and enhance the rigidity and stability of these proteins. Sugar metabolism resulting in the generation of ATP and reducing agent (NADPH), as well as the expression of some key enzymes (dehydrogenases) were also upregulated by DBP treatment. Moreover, a diverse bacterial community appears to utilize sugar, suggesting that there are widespread effects of DBP contamination on soil microbial ecosystems. The results of this study provide a theoretical basis for investigating the toxicological effects of DBP on microbes in black soil.
Показать больше [+] Меньше [-]Cell-based assays seem not to accurately predict fish short-term toxicity of pesticides
2019
Rodrigues, Elsa T. | Varela, Ana T. | Pardal, Miguel A. | Oliveira, Paulo J.
A key action of current aquatic environmental sciences is the determination of concentration-response assessments to quantitatively measure the risk of pollutants, and fish lethal tests are still a regulatory requirement for assessing the environmental risk of both new and existing substances in the aquatic compartment. However, animal health and welfare aspects, as well as the time and resources required to support fish lethal testing, stimulate research for alternative in vitro methods, and cell-based assays are considered as one such alternative. The first goal of the present study was to compile existing fish short-term toxicity and cell toxicity data of pesticides through a scientific literature search, and relate in vivo and in vitro results to identify sensitive cell models, mammalian-, fish- or arthropod-derived. Discovering cell models which are sensitive is of great importance, since the risk of false negatives, believed to be the main limitation of cell-based assays as an alternative to fish tests, may decrease. As to the second goal, this study also determined and compared cell toxicity results for 12 pesticides using rat cardiomyoblast H9c2(2–1) cells with the corresponding fish LC₅₀,₉₆ₕ (50% lethal concentration at 96 h of exposure) values collected in literature. On the whole, the in vivo/in vitro ratio was obtained for 50 pesticides belonging to 23 groups, and presented only 27% of positive results, thus confirming the low sensitivity of cell-based assays in relation to fish lethal data for pesticides. In general, cell-based assays still do not seem to be an alternative to the regulatory short-term fish assay for pesticides, making further studies necessary.
Показать больше [+] Меньше [-]Inheritance, stability, cross-resistance, and life history parameters of a clothianidin-selected strain of house fly, Musca domestica Linnaeus
2021
Shah, Rizwan Mustafa | Shad, Sarfraz Ali
The house fly, Musca domestica L., is a cosmopolitan insect pest of public and animal health importance that serves as a mechanical vector of pathogens. Aimed at prospective resistance management to reduce environmental pollution, we characterized the inheritance pattern, realized heritability, fitness cost, cross resistance, stability and mechanism of clothianidin resistance in M. domestica that were collected from the poultry farm. By continuous selection with clothianidin for 11 generations, the clothianidin selected M. domestica strain (Clotha-SEL) developed a 3827-fold resistance compared to a susceptible strain. However, resistance to clothianidin was proved to be unstable when selection with clothianidin was removed for five generations (G₇ to G₁₂). Inheritance pattern analysis at G₈ of Clotha-SEL (RR = 897) revealed that resistance to clothianidin was polygenic, autosomal and incompletely dominant. Realized heritability (h²) for resistance value was 0.38 (at G₁₁) in the tested strain. Synergist bioassays showed that microsomal oxidases and esterases might not contribute significantly in resistance evolution. Fitness costs of clothianidin resistance were present, for example, reduction in growth potential of the Clotha-SEL strain in comparison to the untreated counterpart strain (UNSEL) was observed. No cross resistance to bifenthrin and fipronil and a very low cross-resistance to spinosad were observed. These insecticides could be alternated with clothianidin as an insecticide resistance management tool to sustain its efficacy for a longer time period. These results shall be utilized to devise a proactive resistance management strategy for use of clothianidin against M. domestica that will be helpful to alleviate the allied threats to environmental and human health.
Показать больше [+] Меньше [-]A review of graphene-based nanomaterials for removal of antibiotics from aqueous environments
2019
Wang, Xuandong | Yin, Renli | Zeng, Lixi | Zhu, Mingshan
Antibiotics as emerging pharmaceutical pollutants have seriously not only threatened human life and animal health security, but also caused environmental pollution. It has drawn enormous attention and research interests in the study of antibiotics removal from aqueous environments. Graphene, an interesting one-atom-thick, 2D single-layer carbon sheet with sp² hybridized carbon atoms, has become an important agent for removal of antibiotic, owing to its unique physiochemical properties. Recently, a variety of graphene-based nanomaterials (GNMs) are reported to efficiently remove antibiotics from aqueous solutions by different technologies. In this review, we summarize different structure and properties of GNMs for the removal of antibiotics by adsorption. Meanwhile, advanced oxidation processes (AOPs), such as photocatalysis, Fenton process, ozonation, sulfate radical and combined AOPs by the aid of GNMs are summarized. Finally, the opportunities and challenges on the future scope of GNMs for removal of antibiotics from aqueous environments are proposed.
Показать больше [+] Меньше [-]Distribution and physicochemical properties of particulate matter in swine confinement barns
2019
Shen, Dan | Wu, Sheng | Li, Zhaojian | Tang, Qian | Dai, Pengyuan | Li, Yansen | Li, Chunmei
Air pollutants accumulated in confined livestock barns could impact the health of animals and staff. Particulate matter (PM) and ammonia (NH3) concentrations are typically high in enclosed livestock houses with weak ventilation. The objective of this study was to investigate the distribution of PM in different size fractions and the levels of NH3 in a high-rise nursery (HN) barn and a high-rise fattening (HF) barn on a swine farm and to analyse the physicochemical properties of fine PM (PM2.5, PM with aerodynamic diameter ≤ 2.5 μm). The concentrations of total suspended particles (TSP, PM with aerodynamic diameter ≤ 100 μm), inhalable PM (PM10, PM with aerodynamic diameter ≤ 10 μm), PM2.5 and NH3 were monitored continuously for 6 d in each barn. The results showed that the concentrations of PM and NH3 varied with position, they were significantly higher inside the barns than outside (P < 0.01) and significantly higher in the forepart than at the rear of the two barns (P < 0.05). In the HF barn, the values of the two parameters were 0.777 ± 0.2 mg m−3 and 26.7 ± 7 mg m−3, respectively, significantly higher than the values observed in the HN barn at all monitored sites (P < 0.05). The PM concentrations increased markedly during feeding time in the two barns. Chemical characteristics analysis revealed that the main sources of PM2.5 in the two barns may have consisted of blowing dust, feed, mineral particles and smoke. In conclusion, the air quality at the forepart was worse than that at the rear of the barns. Activities such as feeding could increase the PM concentrations. The components of PM2.5 in the two barns were probably blowing dust, feed, mineral particles and smoke from outside.
Показать больше [+] Меньше [-]Temporal dynamics of SO2 and NOX pollution and contributions of driving forces in urban areas in China
2018
Zhao, Shuang | Liu, Shiliang | Hou, Xiaoyun | Cheng, Fangyan | Wu, Xue | Dong, Shikui | Beazley, Robert
SO₂ and NOX pollution have significantly reduced the air quality in China in past decades. Haze and acid rain have negatively affected the health of animals, plants, and human beings. Documented studies have shown that air pollution is influenced by multiple socioeconomic driving forces. However, the relative contributions of these driving forces are not well understood. In this study, using the structural equation model (SEM), we quantified the contributing effects of various forces driving air pollution in 2015 in prefecture-level cities of China. Our results showed that there has been significant control of SO₂ pollution in the past 20 years. The annual average SO₂ concentration has dropped from 83 μg/m³ in 1996 to 21 μg/m³ in 2015, while the annual average NOX concentration has increased from 47 μg/m³ in 1996 to 58 μg/m³ in 2015. We evaluated data on the annual average concentrations of SO₂, which in some cities may mask the differences of SO₂ concentrations between different months. Hence, SO₂ pollution should continue to be controlled in accordance with existing policies and regulations. However, we suggest that NOX should become the new focus of air pollution prevention and treatment. The SEM results showed that industrial scale, city size, and residents’ activities have a significant impact on NOX pollution. Among these, industrial scale had the highest contribution. The findings from our study can provide a theoretical basis for the formulation of NOX pollution control policy in China.
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