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Tungsten oxide nanoparticles (WO3 NPs) have now been employed by various products including electronics, smart screens, gas-biosensors, water purifiers, disinfectants, and biomedical applications. Despite this wide-ranging adoption, little research has investigated their potential endpoint biomarkers in different in vivo models. We therefore propose the use of Drosophila melanogaster as a testing model in assessing genotoxic risks of exposure to WO3 NPs. Our study examined toxicity, phenotypic alterations, locomotor behavior (climbing assay), intracellular oxidative stress (ROS), DNA damage (Comet assay), and somatic recombination (wing spot assay) in Drosophila melanogaster after exposure to WO3 NPs (43.71 ± 1.59 nm) and microparticulated (MPs) of WO3. Drosophila larvae were exposed to the test materials via ingestion at doses ranging between 1 and 10 mM, and two greatest doses of NPs (5 and 10 mM) were found to cause mutagenic/recombinogenic effects, while the MPs caused no effects. Wing-spot assay detected genotoxic activity of NPs mostly through somatic recombination, and Comet assay showed DNA damage after exposure to NPs at certain doses (1, 2.5, 5, and 10 mM). Other observations included ROS generation in hemocytes, phenotypic alterations in the mouths and wings of adult flies, and impaired locomotor behavior. This is the first research to report genotoxic evidence on the impact of WO3 exposure in Drosophila larvae, highlighting the significance of this model organism in exploring the potential biological impact of nanoparticles and MPs of WO3. The results of our in vivo testing should make a vital contribution to the existing database on the genotoxicity of WO3 NPs. [ABSTRACT FROM AUTHOR]

Boron trioxide nanoparticles (B2O3 NPs) have recently been widely used in a range of applications including electronic device technologies, acousto‐optic apparatus fields, and as nanopowder for the production of special glasses. We propose Drosophila melanogaster as a useful in vivo model system to study the genotoxic risks associated with NP exposure. In this study, we have conducted a genotoxic evaluation of B2O3 NPs (size average 55.52 ± 1.41 nm) and its ionic form in D. melanogaster. B2O3 NPs were supplied to third instar larvae at concentrations ranging from 0.1–10 mM. Toxicity, intracellular oxidative stress (reactive oxygen species, ROS), phenotypic alterations, genotoxic effect (via the wing somatic mutation and recombination test, SMART), and DNA damage (via Comet assay) were the end‐points evaluated. B2O3 NPs did not cause any mutagenic/recombinogenic effects in all tested non‐toxic concentrations in Drosophila SMART. Negative data were also obtained with the ionic form. Exposure to B2O3 NPs and its ionic form (at two highest concentrations, 2.5 and 5 mM) was found to induce DNA damage in Comet assay. Additionally, ROS induction in hemocytes and phenotypic alterations were determined in the mouths and legs of Drosophila. This study is the first study reporting genotoxicity data in the somatic cells of Drosophila larvae, emphasizing the importance of D. melanogaster as a model organism in investigating the different biological effects in a concentration‐dependent manner caused by B2O3 NPs and its ionic form. The obtained in vivo results contribute to improvement the genotoxicity database on the B2O3 NPs. Relatively rare in the Earth's crust, boron is one of the essential trace elements immensely beneficial for a range of living organisms. Researchers have recently shown an increased interest in the regulatory viewpoint of boron compounds, albeit without yielding consistent results. We have extensively characterized their interaction with the somatic cells of the Drosophila larvae by using genotoxicity endpoints including mutagenic/recombinogenic activities, oxidative stress, DNA damage, and phenotypic alterations. [ABSTRACT FROM AUTHOR]

1,4-Dioxane (DXN) is used as solvent in different consumer products including cosmetics, paints, surfactants, and waxes. In addition, DXN is released as an unwanted contaminating by-product as a result of some reactions including ethoxylation of alcohols, which occurs with in personal care products. Consequently, DXN pollution was detected in drinking water and is considered as an environmental problem. At present, the genotoxicity effects attributed to DXN are controversial. The present study using an in vivo model organism Drosophila melanogaster aimed to determine the toxic/genotoxic, mutagenic/recombinogenic, oxidative damage as evidenced by ROS production, phenotypic alterations as well as behavioral and developmental alterations that are closely related to neuronal functions. Data demonstrated that nontoxic DXN concentration (0.1, 0.25, 0.5, or 1%) induced mutagenic (1%) and recombinogenic (0.1, 0.25, or 0.5%) effects in wing spot test and genotoxicity in hemocytes using comet assay. The nontoxic concentrations of DXN (0.1, 0.25, 0.5, or 1%) significantly increased oxidative stress, climbing behavior, thermal sensivity and abnormal phenotypic alterations. Our findings show that in contrast to in vitro exposure, DXN using an in vivo model Drosophila melanogaster this compound exerts toxic and genotoxic effects. Data suggest that additional studies using other in vivo models are thus warranted. [ABSTRACT FROM AUTHOR]

Salt pollution of freshwater ecosystems represents a major threat to biodiversity, and particularly to interactions between free‐living species and their associated parasites. Acanthocephalan parasites are able to alter their intermediate host's phenotype to reach final hosts, but this process could be affected by salt pollution, thereby compromising survival of the parasite.We experimentally assessed the impact of salt on the extended phenotype of the parasite Pomphorhynchus laevis in their intermediate host, the amphipod Gammarus pulex, based on three amphipod behaviours: distance covered in flowing water, phototaxis, and geotaxis. We hypothesised that: (1) salt pollution negatively affected the behaviour of uninfected gammarids, and (2) that P. laevis could maintain their capacity to manipulate their host despite this pollution.All three amphipod behaviours were altered by P. laevis: infected G. pulex covered a greater distance, were less photophobic and were more attracted to the water surface than uninfected amphipods, in control or salt‐polluted water. However, salinity reduced distance covered in flowing water and increased attraction to the water surface of uninfected and infected G. pulex. For the phototaxis behaviour, P. laevis enhanced this capacity of manipulation in salt‐polluted water compared to control water.Pomphorhynchus laevis can still manipulate the behaviour of their intermediate host in salt‐polluted water. Acanthocephalan parasites have not been known to be able to manipulate their intermediate host when under pollution stress. Trophic interactions, but not the chances of parasite transmission to their definitive host, appear to be affected by salt pollution.Our study indicates that behavioural modifications induced by complex lifecycle parasites should be more considered in the context of growing concentrations of chemical pollutants in some freshwater ecosystems. Interspecific interactions, and particularly host–parasite relationships, are a key component of ecosystem stability and their alteration could result in major changes in energy flow. [ABSTRACT FROM AUTHOR]

To investigate the association of genetic markers in ESR1 and ESR2 with craniofacial measurements. Cross-sectional study. School of Dentistry of Ribeirão Preto, University of São Paulo. A total of 146 biologically unrelated, self-reported Caucasian Brazilians with no syndromic conditions were included. Sagittal and vertical measurements (ANB, S-N, Ptm'-A', Co-Gn, Go-Pg, N-Me, ANS-Me, S-Go and Co-Go) from lateral cephalograms were examined for craniofacial evaluation. DNA was extracted from saliva and genetic markers in ESR1 (rs2234693 and rs9340799) and in ESR2 (rs1256049 and rs4986938) were analysed by real-time polymerase chain reaction. Hardy–Weinberg equilibrium was evaluated using the Chi-square test within each marker. The associations between craniofacial dimensions and genotypes were analysed by linear regression and adjusted by sex and age. The established alpha was 5%. Individuals carrying CC in ESR1 rs2234693 had a decrease of –3.146 mm in ANS-Me (P = 0.044). In addition, rs4986938 in ESR2 was associated with S-N measurement (P = 0.009/ ß = –3.465). This marker was also associated with Go-Pg measurement, in which the CC genotype had a decrease of –3.925 mm in the length of the mandibular body (P = 0.043). The present study suggests that in ESR1 and ESR2 are markers for variations in the craniofacial dimensions. However, further research should confirm the results. [ABSTRACT FROM AUTHOR]

The frog embryo teratogenesis assay- Xenopus (FETAX) is an established method for the evaluation of the developmental toxicities of chemicals. To develop an enhanced FETAX that is appropriate for common environmental contaminants, we exposed Xenopus tropicalis embryos to eight compounds, including tributyltin, triphenyltin, CdCl 2 , pyraclostrobin, picoxystrobin, coumoxystrobin, all - trans -retinoic acid and 9 - cis -retinoic acid. Multiple malformations were induced in embryos particularly following exposure to tributyltin, triphenyltin and pyraclostrobin at environmentally relevant concentrations. Based on the range of observed malformations, we proposed a phenotypic assessment method with 20 phenotypes and a 0–5 scoring system. This derived index exhibited concentration-dependent relationships for all of the chemicals tested. Furthermore, the phenotype profiles were characteristic of the different tested chemicals. Our results indicate that malformation phenotypes can be quantitatively integrated with the primary endpoints in conventional FETAX assessments to allow for increased sensitivity and measurement of quantitative effects and to provide indicative mechanistic information for each tested chemical. [ABSTRACT FROM AUTHOR]

xThe 70-kDa heat shock protein (HSP70) is highly conserved among both prokaryotes and eukaryotes and plays essential roles in diverse cellular functions not only under stress but also under normal conditions. In the protozoan Leishmania infantum, the causative agent of visceral leishmaniasis, HSP70 is encoded by two HSP70 genes. Here, we describe the phenotypic alterations of HSP70-II-deficient (Δhsp70-II) promastigotes. The absence of HSP70-II caused a major alteration in growth as the promastigotes reached stationary phase. In addition, aberrant forms were frequently observed in Δhsp70-II mutant cultures. An accumulation of cells in the G2/M phase in cultures of the Δhsp70-II mutant was determined by flow cytometry. Furthermore, Δhsp70-II promastigotes showed a limited capacity of multiplication within macrophages, even though attachment to and uptake by macrophages did not differ significantly from the wild-type. Moreover, Δhsp70-II was highly attenuated in BALB/c mouse experimental infections. In mutants re-expressing HSP70-II, the growth rate was restored, the normal morphology was recovered, and interactions with macrophages increased. However, promastigotes reexpressing HSP70-II did not recover their virulence. Overall, these data highlight the essential role played by HSP70-II expression in Leishmania virulence, pointing to this gene as a promising target for therapeutic interventions. [ABSTRACT FROM AUTHOR]

Over the last two centuries, the marine life of the Eastern Mediterranean has been influenced by two major factors: one is beneficial, and concerns species migration, such as the opening of the Suez Canal, which enriched the impoverished eastern Mediterranean Sea with over 300 species of fish and invertebrates of Red Sea origin; while the other, a negative and possibly wider-reaching factor, is that of man-made pollution, which has induced unpredictable changes, destabilizing the biological world in both magnitude and duration. Initially cryptic, the effects caused by pollutants first occur at the biochemical and cellular levels of an organism, causing alterations and deviations from the normal, strongly mobilizing its defense systems. Conventional methodologies of ecological analyses, based on species and specimen numbers, cannot detect such alterations. Studying several mollusk populations from polluted and reference sites of the Red Sea and Mediterranean littoral of Israel, we used specific markers for in vivo and in vitro studies to expose the state of micronucleation; levels of defense transport systems such as membrane transport system of organic anions (SATOA) and organic cations (OCT); the state of the multi-xenobiotic resistance-mediating transporter (MXRtr). Based on fluorescent microscopy and microfluorometry, these markers offer powerful tools to expose cryptic changes in the affected populations and provide data necessary for planning and management to protect animal communities and preserve their biological diversity. Comparative analysis of general gene-expression in polluted and reference sites indicates that stress factors have differentially affected the various biological taxa and separated phenotypic sub-populations, producing a novel type of punctuated selection. Such factors, although negative in their influences, in some instances altering the qualities of organisms, and establishing alterations in their hereditary information, pre-adapt them to survive and succeed in new situations. [Copyright &y& Elsevier]

The effects of maternal glucocorticoids (e.g. corticosterone, CORT) on offspring interest biologists due to increasing environmental perturbations. While little is known about the impact of maternal CORT on offspring fitness, it may modulate telomere length and compromise offspring health. Here, we use a modified real-time quantitative PCR assay to assess telomere length using small DNA quantities (<60 ng). We tested the hypothesis that increased maternal CORT during gestation decreases offspring telomere length. While CORT-driven telomere shortening is well established within individuals, cross-generational effects remain unclear. We treated wild-caught gravid female eastern fence lizards (Sceloporus undulatus) with daily transdermal applications of CORT, at ecologically relevant levels, from capture to laying. Maternal CORT treatment did not alter maternal telomere length, although baseline maternal CORT concentrations had a weak, negative correlation with maternal telomere length. There was no relation between mother and offspring telomere length. There was a trend for maternal CORT treatment to shorten telomeres of sons but not daughters. Our treatment replicated exposure to a single stressor per day, likely underestimating effects seen in the wild where stressors may be more frequent. Future research should further explore fitness consequences of maternal CORT effects. [Display omitted] • Telomere- endcaps of DNA- shortening is associated with disease and cell senescence. • Corticosterone can reduce offspring lifespan, possibly via telomere shortening. • Adult lizards with higher baseline corticosterone tend towards shorter telomeres. • Application of corticosterone to gravid females has sex-specific effects on offspring. • Maternal treatment tends to shorten their sons' but not their daughters' telomeres. [ABSTRACT FROM AUTHOR]

Industrial use of nanomaterials is rapidly increasing, making the effects of these materials on the environment and human health of critical concern. Standard nanotoxicity evaluation methods rely on detecting cell death or major dysfunction and will miss early signs of toxicity. In this work, the use of rapid and sensitive nanosensors that can efficiently detect subtle phenotypic changes on the cell surface following nanomaterial exposure is reported. Importantly, the method reveals significant phenotypic changes at dosages where other conventional methods show normal cellular activity. This approach holds promise in toxicological and pharmacological evaluations to ensure safer and better use of nanomaterials., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)