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Melanoma is a type of tumor that originates from melanocytes. Irradiation of melanin with UVA and visible light can produce reactive oxygen species (ROS) such as singlet molecular oxygen (

Every day, scientists make discoveries that help improve human health and wellness. Many medicines are discovered in nature, like toxins from animals. We decided to study a fish called Copper Joe toadfish (Thalassophryne nattereri) and found that a small molecule in the fish’s venom, called TnP, can help damaged organs and tissues. However, before any molecule can be used in humans, it must be tested on laboratory animals. These tests are called pre-clinical trials and are important to prove that a treatment is safe for humans. Our study tested TnP in zebrafish and found that it is safe and has no toxic effects on the developing fish. In the future, scientists can continue researching TnP, and hopefully, someday, it will be developed into a medicine to help thousands of people around the world who are suffering from diseases that cause inflammation.

Microplastics (MP) are emerging contaminants with the capacity to bind and transport hydrophobic organic compounds of environmental concern, such as polybrominated diphenyl ethers (PBDEs). The aim of this study was to investigate the ingestion of nylon (polyamide) MP alone and when associated with PBDEs and their effects on Chironomus sancticaroli larvae survival and microbiome structure. Survival, PBDE uptake and microbial community composition were measured in fourth instar larvae exposed for 96 h to BDEs- 47, 99, 100 and 153 in the presence and absence of 1% w/w MP in sediment. Microbiome community structures were determined through high throughput sequencing of 16S small subunit ribosomal RNA gene (16S rRNA). Initial experiments showed that larvae ingested MP faster at 0.5% w/w MP, while depuration was more efficient at 1% w/w MP, although retention of MP was seen even after 168 h depuration. No mortality was observed as a result of PBDEs and MP exposure. MP had a negative effect on PBDE concentration within larvae (η2 = 0.94) and a negative effect on sediment concentrations (η2 = 0.48). In all samples, microbial communities were dominated by Alphaproteobacteria, Betaproteobacteria, Actinobacteria and Gammaproteobacteria. Bacterial alpha diversity was not significantly affected by PBDEs or MP exposure. However, the abundance of discrete bacterial taxa was more sensitive to MP (X2 = 45.81, p = 0.02), and PBDE exposure. Our results highlight that C. sancticaroli showed no acute response to MPs and PBDEs, but that MPs influenced bacterial microbiome structure even after only short-term acute exposure.

The Butantan Institute is a pioneering Brazilian health sciences institution, which also houses a large science park with museums that contribute to ongoing science education for schools and the wider community. In recent years, as part of Butantan Institute’s Plataforma Zebrafish™, zebrafish embryos have been used for the dissemination of scientific knowledge during on-site events and as part of outreach campaigns to non-scientific audiences, mostly children. The aim of this work is mainly to demystify the activities of the scientific researcher, highlight the role of science in the furthering of knowledge, and increase public interest and confidence in science. In this article, the Institute’s ‘Plataforma Zebrafish Open Doors’ programme is described, which offered guided tours of the laboratory facilities. The tours gave visitors the opportunity to observe zebrafish research and embryo development, and to use the knowledge gained from this experience as a framework for understanding fundamental ethical issues. During the 2-day event, around 800 visitors (most of them school-age children) attended. Together with the guided tours, our experience of outreach offered meaningful opportunities to bring children and members of the public closer to science and ‘real-life’ scientists, hopefully inspiring and encouraging the next generation of scientists. It also gave the scientists an opportunity to engage more closely with wider society. We believe that these activities also substantially contribute to the wider dissemination of relevant experimental results that have been obtained with public funding and that impact society in general.

The oil spill off the Brazilian coast, which reached especially the Northeast in 2019, is known as the biggest disaster of its kind in the country's history. Accidents of this type are not new; however, this episode had enormous proportions with 11 states, 130 municipalities, and more than 1,000 locations affected by oil stains or residues. Considering the extent of this environmental tragedy associated with the Brazilian biodiversity peculiarities is immeasurable the damages to fauna and protected areas, especially those that are more sensitive, such as mangroves and coral reefs. It is known that the oil source is Venezuela, but those responsible for the disaster are not known yet. The neglect in investigating events and decision making to deal with the incident aggravated the effects on habitats and local communities. The first occurrence on the coast happened on August 30, 2019, and the most significant number of affected locations was recorded during November. However, even without a complete solution of the case, in January 2020, the monitoring and evaluation group responsible for monitoring, remediation, and protection actions, officially announce the beginning of the demobilization protocol, establishing the termination points, which represent the end of monitoring in most of the areas. Contradictorily, in some locations considered sensitive, the end of the work will be carried out “even with the significant presence of oil in the area”. Studies in the literature indicate that highly weathered oil, which has a high molecular weight and low solubility PAHs, can have toxic effects as representative or higher than its non-weathered counterpart. These findings contradict a classic paradigm that crude oil with low molecular weight and more volatile PAHs are primarily responsible for toxicity. Regardless of the damages caused by the activities of total oil removal compared to natural degradation, there is a disregard for this issue, a deficit of environmental agencies employees and investments in this sector. Given the initiative to demobilize activities related to this serious accident, this review seeks to contextualize similar accidents, synthesize the events, dimensions, and environmental consequences related to the most significant ecological disaster on the Brazilian coast and discuss its likely environmental impacts considering the physical-chemical characteristics of the pollutant. In recent years, Brazil has been the scene of unprecedented disasters. The oil in the Northeast, along with the Mariana and Brumadinho dam rupture and the fires in the Amazon shows the lack of critical assessment of the environmental issue in Brazil, and what appears to be a society plan that, through structural measures, allows cases of environmental degradation to happen with impunity and the conservation of natural resources is genuinely not a priority of government actions.

The environmental and occupational risk we confront from agricultural chemicals increases as their presence in natural habitats rises to hazardous levels, building a major part of the exposome. This is of particular concern in low- and middle-income countries, such as Brazil, known as a leading producer of agricultural commodities and consumer of pesticides. As long as public policies continue to encourage the indiscriminate use of pesticides and governments continue to support this strategy instead of endorsing sustainable agricultural alternatives, the environmental burden that damages epithelial barriers will continue to grow. Chronic exposure to environmental contaminants in early life can affect crucial barrier tissue, such as skin epithelium, airways, and intestine, causing increased permeability, leaking, dysbiosis, and inflammation, with serious implications for metabolism and homeostasis. This vicious cycle of exposure to environmental factors and the consequent damage to the epithelial barrier has been associated with an increase in immune-mediated chronic inflammatory diseases. Understanding how the harmful effects of pesticides on the epithelial barrier impact cellular interactions mediated by endogenous sensors that coordinate a successful immune system represents a crucial challenge. In line with the epithelial barrier hypothesis, this narrative review reports the available evidence on the effects of pesticides on epithelial barrier integrity, dysbiosis, AhR signaling, and the consequent development of immune-mediated inflammatory diseases.

Background The Natterin protein family was first discovered in the venom of the medically significant fish Thalassophryne nattereri, and over the last decade natterin-like genes have been identified in various organisms, notably performing immune-related functions. Previous findings support natterin-like genes as effector defense molecules able to activate multiprotein complexes driving the host innate immune response, notably due to the pore-forming function of the aerolysin superfamily members. Herein, employing a combination of the CRISPR/Cas9 depletion system, phenotype-based screening, and morphometric methods, we evaluated the role of one family member, LOC795232, in the embryonic development of zebrafish since it might be implicated in multiple roles and characterization of the null mutant is central for analysis of gene activity. Results Multiple sequence alignment revealed that the candidate natterin-like has the highest similarity to zebrafish aep1, a putative and better characterized fish-specific defense molecule from the same family. Compared to other species, zebrafish have many natterin-like copies. Whole-mount in situ hybridization confirmed the knockout and mutant embryos exhibited epiboly delay, growth retardation, yolk sac and heart edema, absent or diminished swim bladder, spinal defects, small eyes and head, heart dysfunction, and behavioral impairment. As previously demonstrated, ribonucleoproteins composed of Cas9 and duplex guide RNAs are effective at inducing mutations in the F0 zebrafish. Conclusions The considerably high natterin-like copies in zebrafish compared to other species might be due to the teleost-specific whole genome duplication and followed by subfunctionalization or neofunctionalization. In the present work, we described some of the natterin-like features in the zebrafish development and infer that natterin-like proteins potentially contribute to the embryonary development and immune response.

Since the first record of the five founder members of the group of Natterin proteins in the venom of the medically significant fish Thalassophryne nattereri, new sequences have been identified in other species. In this work, we performed a detailed screening using available genome databases across a wide range of species to identify sequence members of the Natterin group, sequence similarities, conserved domains, and evolutionary relationships. The high-throughput tools have enabled us to dramatically expand the number of members within this group of proteins, which has a remote origin (around 400 million years ago) and is spread across Eukarya organisms, even in plants and primitive Agnathans jawless fish. Overall, the survey resulted in 331 species presenting Natterin-like proteins, mainly fish, and 859 putative genes. Besides fish, the groups with more species included in our analysis were insects and birds. The number and variety of annotations increased the knowledge of the obtained sequences in detail, such as the conserved motif AGIP in the pore-forming loop involved in the transmembrane barrel insertion, allowing us to classify them as important constituents of the innate immune defense system as effector molecules activating immune cells by interacting with conserved intracellular signaling mechanisms in the hosts.

Brazil is a global agricultural commodity producer and the largest consumer of pesticides. Pesticide use in Brazil comprised 549 280 tons in 2018. In the country, soybean, corn, and sugar cane are extensively produced, which are the most pesticides demanding crops. In the last years, the records of new pesticides were the highest in the historical series. They can persist in soil or water, accumulate in organisms, and contaminate workers and the general population through the air, water, or food. This review aimed to gather toxicological data obtained by animal models exposed to 4 pesticides: glyphosate, chlorpyrifos, abamectin, and 2,4-D. An additional goal was to compose an overview of how this subject has been approached, surveying which research groups are working on this field, where they are located, and relations with pesticides used in those regions. We collected the papers from the platforms PubMed, Scopus, Scielo, and Web of Science, performed in Brazil from 2014 to 2019. After two-step blind selection using the software Rayyan QCRI by different authors, 67 studies were selected to extract data. We observed that research is more concentrated in the South region, followed by the Southeast and Midwest, with 43%, 32%, and 23% of the studies, respectively. The prevalent institutions are from the states of Rio Grande do Sul, Sao Paulo, and Goias. The effects on a variety of biomarkers help predict the potential risks to humans and nontarget organisms. The prevalent animal model was fish (36%). Overall, the main toxic effects evaluated were mortality, abnormalities in the blood cells, developmental abnormalities, and behavior alterations. Integr Environ Assess Manag 2021;17:507-520. © 2020 SETAC.

Our recent data show the valuable potential of TnP for the development of a new and safe anti-inflammatory drug due to its ability to control the traffic and activation of leukocytes in response to inflammation. Although there is considerable knowledge surrounding the cellular mechanisms of TnP, less is known about the mechanistic molecular role of TnP underlying its immunomodulatory functions. Here, we conducted investigations to identify whether miRNAs could be one of the molecular bases of the therapeutic effect of TnP. Using a zebrafish model of neutrophilic inflammation with a combination of genetic gain- and loss-of-function approaches, we showed that TnP treatment was followed by up-regulation of only four known miRNAs, and mature dre-miR-26a-1, herein referred just as miR-26a was the first most highly expressed. The knockdown of miR-26a ubiquitously resulted in a significant reduction of miR-26a in embryos, accompanied by impaired TnP immunomodulatory function observed by the loss of the control of the removal of neutrophils in response to inflammation, while the overexpression increased the inhibition of neutrophilic inflammation promoted by TnP. The striking importance of miR-26a was confirmed when rescue strategies were used (morpholino and mimic combination). Our results identified miR-26a as an essential molecular regulator of the therapeutic action of TnP, and suggest that miR-26a or its targets could be used as promising therapeutic candidates for enhancing the resolution of inflammation.

Graphical abstract, Highlights • TnP has been indicated for chronic inflammatory diseases, multiple sclerosis. • Zebrafish is an alternative animal model for preclinical drug development. • Preclinical toxicology studies have shown that TnP has a wide therapeutic index range from 1 nM to 10 μM. • TnP did not induce cardiotoxic effect or cardiac dysfunction. • TnP crossed the blood-brain barrier without causing neurotoxicity., The patented anti-inflammatory peptide TnP had its effectiveness recently confirmed in vivo in a murine model of multiple sclerosis and asthma. In this work, the safety of the TnP was evaluated in investigative toxicology tests using zebrafish (Danio rerio) as a model. We conducted the OECD #236 test to investigate effects of the TnP on the survival, hatching performance, and morphological formation of zebrafish embryos. After determining these endpoints, morphometric analysis termination of locomotion eartbeat rate in zebrafish larvae were evaluated to identify adverse effects such as neurotoxicity and cardiotoxicity. The results highlight a wide therapeutic index for TnP with non-lethal and safe doses rom 1 nM to 10 μM, without causing neurotoxicity or cardiotoxic effect. The low frequencyf abnormalities by TnP was associated with high safety of the molecule and the developing embryo's ability to process and eliminate it. TnP crossed the blood-brain barrier without disturbing the normal architecture of forebrain, midbrain and hindbrain. Our data reinforce the importance of zebrafish as an accurate investigative toxicology model to assess acute toxicity as well as cardiotoxicity and neurotoxicity of molecules in the preclinical phase of development.

Genotoxic effects of nanomaterials (NMs) have been controversially reported in literature, and the mode of action (MoA) via DNA oxidation is cited as the main damage caused by them. Evidence of nano-silver as a crosslinker has been previously reported by the present research team in an in vivo fish genotoxicity study. Thus, aiming to confirm the evidence about NMs as crosslinker agent, the present investigation elucidated the genotoxic potential of NMs and their genotoxic MoA through in vitro assay with RTG-2 cells line (rainbow trout gonadal) by exposure to nano-silver (PVP-coated) and nano-titanium. The types and levels of DNA damage were assessed by the Comet assay (standard alkaline, hOGG1-modified alkaline, and two crosslink-modified alkaline versions). It was demonstrated that the use of the standard alkaline Comet assay alone may inaccurately predict the genotoxicity of NMs since oxidative and crosslink DNA damages were also verified in RTG-2 cells when assessed by the modified versions of the alkaline protocol. More importantly, it was confirmed that both nano-silver and nano-titanium acted as DNA-protein crosslinkers through the Comet assay version with proteinase K. As both nano-silver and nano-titanium present a great risk to aquatic life, these findings reinforce the need of genotoxicity testing strategies that encompass the assessment of different types of DNA damage, in order to ensure an accurate prediction of the genotoxic potential of NMs.

Made available in DSpace on 2018-12-11T16:54:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-08-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação Araucária Fundação de Amparo à Pesquisa do Estado de Goiás Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The textile dyeing industry is one of the main sectors contributing to environmental pollution, due to the generation of large amounts of wastewater loaded with dyes (ca. 2–50% of the initial amount of dyes used in the dye baths is lost), causing severe impacts on human health and the environment. In this context, an ecotoxicity testing battery was used to assess the acute toxicity and genotoxicity of the textile dyes Direct Black 38 (DB38; azo dye) and Reactive Blue 15 (RB15; copper phthalocyanine dye) on different trophic levels. Thus these dyes were tested using the following assays: Filter paper contact test with earthworms (Eisenia foetida); seed germination and root elongation toxicity test (Cucumis sativus, Lactuca sativa and Lycopersicon esculentum); acute immobilization test (Daphnia magna and Artemia salina); and the Comet assay with the rainbow trout gonad-2 cell fish line (RTG-2) and D. magna. Neither phytotoxicity nor significant effects on the survival of E. foetida were observed after exposure to DB38 and RB15. Both dyes were classified as relatively non-toxic to D. magna (LC50 > 100 mg/L), but DB38 was moderately toxic to A. salina with a LC50 of 20.7 mg/L. DB38 and RB15 induced significant effects on the DNA of D. magna but only DB38 caused direct (alkaline comet assay) and oxidative (hOGG1-modified alkaline comet assay) damage to RTG-2 cells in hormetic responses. Therefore, the present results emphasize that a test battery approach of bioassays representing multiple trophic levels is fundamental in predicting the toxicity of textile dyes, aside from providing the information required to define their safe levels for living organisms in the environment. Faculty of Pharmacy (FF) Federal University of Goiás (UFG) Departament of Genetics Federal University of Paraná (UFPR) Unit of Experimental Toxicology and Ecotoxicology (UTOX) Barcelona Science Park (PCB) Association of Biologists of Catalonia (CBC) Faculty of Pharmaceutical Sciences of Ribeirão Preto (FCFRP) University of São Paulo (USP) National Institute for Alternative Technologies of Detection Toxicological Evaluation and Removal of Micropollutants and Radioactives (INCT-DATREM) UNESP Institute of Chemistry, P.O. Box 355 National Institute for Alternative Technologies of Detection Toxicological Evaluation and Removal of Micropollutants and Radioactives (INCT-DATREM) UNESP Institute of Chemistry, P.O. Box 355 CNPq: 465571/2014-0 FAPESP: 2010/01487-2

Ibuprofen is a pharmaceutical drug widely used by the global population and it has been found in aquatic ecosystems in several countries. This study evaluated the effects of ibuprofen in environmental concentrations (0, 0.1, 1 and 10 μg/L) on the freshwaterspecies Rhamdia quelen exposed for 14 days. In the posterior kidney, ibuprofen increased glutathione-S-transferase activity in all groups exposed. Furthermore, increased glutathione peroxidase activity and the levels of reduced glutathione in the group exposed to 10 μg/L. Ibuprofen decreased the carbonic anhydrase activity in the posterior kidney in all exposed groups, and increased the activity in the gills in group exposed to 0.1 μg/L. The levels of plasma magnesium increased in groups exposed to 0.1 and 1 μg/L. In the blood, ibuprofen decreased the white blood cell count in groups exposed to 0.1 e 1.0 μg/L. Therefore, these results indicated that ibuprofen caused nephrotoxicity and demonstrated immunosuppressive effect in Rhamdia quelen .

Nanotechnologies are at the center of societal interest, due to their broad spectrum of application in different industrial products. The current concern about nanomaterials (NMs) is the potential risks they carry for human health and the environment. Considering that NMs can reach bodies of water, there is a need for studying the toxic effects of NMs on aquatic organisms. Among the NMs' toxic effects on fish, the interactions between NMs and the nervous system are yet to be understood. For this reason, our goal was to assess the neurotoxicity of polyvinylpyrrolidone coated silver nanospheres [AgNS (PVP coated)] and compare their effects in relation to silver ions (Ag+) in carnivorous Hoplias intermedius fish after acute and subchronic trophic exposure through the analysis of morphological (retina), biochemical (brain) and genetic biomarkers (brain and blood). For morphological biomarkers, damage by AgNS (PVP coated) in retina was found, including morphological changes in rods, cones, hemorrhage and epithelium rupture, and also deposition of AgNS (PVP coated) in retina and sclera. In the brain biomarkers, AgNS (PVP coated) did not disturb acetylcholinesterase activity. However, lowered migration of the DNA tail in the Comet Assay of blood and brain cells was observed for all doses of AgNS (PVP coated), for both acute and subchronic bioassays, and in a dose-dependent manner in acute exposure. Ag+ also reduced the level of DNA damage only under subchronic conditions in the brain cells. In general, the results demonstrated that AgNS (PVP coated) do not cause similar effects in relation to Ag+. Moreover, the lowered level of DNA damage detected by Comet Assay suggests that AgNS (PVP coated) directly interacts with DNA of brain and blood cells, inducing DNA-DNA or DNA-protein crosslinks. Therefore, the AgNS (PVP coated) accumulating, particularly in the retina, can lead to a competitive disadvantage for fish, compromising their survival.

miRNAs regulate gene expression post-transcriptionally in various processes, e.g., immunity, development, and diseases. Since their experimental analysis is complex, in silico target prediction is important for directing investigations. TnP is a candidate peptide for anti-inflammatory therapy, first discovered in the venom of Thalassophryne nattereri, which led to miRNAs overexpression in LPS-inflamed zebrafish post-treatment. This work aimed to predict miR-21, miR-122, miR-731, and miR-26 targets using overlapped results of DIANA microT-CDS and TargetScanFish software. This study described 513 miRNAs targets using highly specific thresholds. Using Gene Ontology over-representation analysis, we identified their main roles in regulating gene expression, neurogenesis, DNA-binding, transcription regulation, immune system process, and inflammatory response. miRNAs act in post-transcriptional regulation, but we revealed that their targets are strongly related to expression regulation at the transcriptional level, e.g., transcription factors proteins. A few predicted genes participated concomitantly in many biological processes and molecular functions, such as foxo3a, rbpjb, rxrbb, tyrobp, hes6, zic5, smad1, e2f7, and npas4a. Others were particularly involved in innate immunity regulation: il17a/f2, pik3r3b, and nlrc6. Together, these findings not only provide new insights into the miRNAs mode of action but also raise hope for TnP therapy and may direct future experimental investigations.

The aquatic environment is the major recipient of wastes containing nanoparticles and other contaminants. Titanium dioxide nanoparticles (NPTiO2) are one of the most produced and used nanoparticle worldwide. This study investigated the toxicity of NPTiO2, as well as the toxicity interaction between NPTiO2 and lead (Pb), in response to genetic and biochemical biomarkers using freshwater fish Rhamdia quelen, as an animal model. The results showed genotoxicity in blood and kidney tissues. No effect of NPTiO2 alone or in co-exposure with Pb on liver genotoxicity were observed. Alterations in the antioxidant hepatic enzymes activities, as well as alterations in glutathione levels indicated that NPTiO2 alone or in co-exposure with Pb can cause antioxidant imbalance. The lipid peroxidation was also raised after exposure to NPTiO2. In general, the results of this study indicated that both NPTiO2 alone and their co-exposure with Pb are capable of producing significant toxic effects in short-term exposure.

Os hidrocarbonetos Aromáticos Policíclicos, como o Naftaleno, são considerados poluentes orgânicos prioritários em estudos ambientais. Alguns apresentam elevado potencial de toxicidade e podem ser precursores de efeitos mutagênicos e carcinogênicos. O teste de micronúcleo é uma ferramenta sensível na detecção de eventos clastogênicos e aneugênicos ocasionados por xenobióticos. O objetivo deste trabalho foi avaliar a mutagenicidade do naftaleno após exposição aguda em um modelo animal e um vegetal. Os bioindicadores foram a espécie de peixe Astyanax altiparanae e a planta Tradescantia pallida purpurea. No teste de micronúcleo písceo nenhum dos tratamentos apresentou diferença significativa com o controle negativo. No teste em células-mãe do grão de pólen de Tradescantia a concentração de 0,3 mgL-1 apresentou mais micronúcleos em relação ao controle negativo. O Trad-MCN demonstrou maior sensibilidade na detecção de quebras e perdas cromossômicas ocasionadas pelo naftaleno.

A pandemia de COVID-19 levantou um antigo debate sobre a natureza dos vírus. Baseado em conceitos estritos, eles não têm metabolismo, homeostase interna, crescimento ou se replicam sem um hospedeiro, portanto, não poderiam estar vivos. A descoberta de vírus gigantes retoma o papel dos vírus na evolução, pois exibem maior complexidade e carregam um genoma extenso, dependendo menos do hospedeiro. Os vírus devem ter evoluído de organismos mais complexos e perdido seus genes temporalmente, reduzindo-os ao essencial. Pela teoria do gene egoísta de Dawkins, a seleção natural atua sobre genes específicos como unidade de seleção. Esse replicador usa veículos transitórios em favor de sua multiplicação, e o aspecto egoísta mantém as características sendo transmitidas. Do ponto de vista da seleção natural, replicadores ou genes virais, que menos replicam, diminuirão em frequência. O fato de manterem a estrutura simples não implica o status inerte dos vírus. Os limites entre vivo versus não-vivo é um contínuo; e essa classificação é mais um debate filosófico e semântico que científico. Esta revisão visa reunir informações sobre a origem dos vírus e a relação com a vida primordial através de uma revisão narrativa da literatura. Por meio do entendimento acerca da onipresença e aspectos evolutivos dos vírus, é possível chegar a um entendimento geral de que estes podem ser classificados como seres vivos, pois expressam informações hereditárias e evoluem através da seleção natural.

Polycyclic aromatic hydrocarbons are one of the most important organic pollutants in environmental studies. The aim of this study was to assess the naphthalene acute toxicity in two fish species, Astyanax lacustris (LLcust, 1875) and Geophagus brasiliensis (Quoy & Gaimard, 1824). The fish were exposed to naphthalene (0.005, 0.03, 0.3, and 3 mgL-1) in water and after that the piscine micronucleus test in erythrocytes, comet assay in blood, liver and gill cells, glutathione S–transferase (GST) activity in the liver, and accumulation of naphthalene in the bile were performed. The susceptibility of the two species was similar and naphthalene was not genotoxic in all tested tissues. The liver GST activity may have been responsible for less damage observed in the liver while the highest DNA damage occurred in blood cells. However, low concentrations of naphthalene in water can stimulate apparent benefits, such as less DNA damage, which would be a compensatory response to an imbalance of homeostasis. The naphthalene is absorbed and can accumulate in the gall bladder, a greater accumulation of PAH was observed in A. lacustris, while G. brasiliensis did not differ from the control. The naphthalene concentrations are not genotoxic to the tested species, although they can potentially accumulate into the body.Keywords: Comet assay. Ecotoxicology. Fish. Genotoxicity. Hormesis.

Hantavirus cardiopulmonary syndrome (HCPS) is an infectious disease caused by hantaviruses of the family Bunyaviridae, and is transmitted by aerosols of excreta of infected rodents. The aim of the present study was to determine antibody levels to hantavirus in the population that lives at frontier of Brazil and Argentina. Participated of the study 405 individuals living in the municipalities of Bandeirante, Santa Helena, Princesa and Tunapolis, state of Santa Catarina, Brazil. IgG antibodies to hantavirus were analyzed in sera by an ELISA that uses a recombinant N protein of Araraquara hantavirus as antigen. The results were also confirmed by immunofluorescent test. Eight individuals showed antibodies to hantavirus (1.97% positivity), with serum titers ranging from 100 to 800. Six seropositives were males, older than 30 years and farmers. Our results reinforce previous data on hantavirus circulation and human infections in the southern border of Brazil with Argentina. Síndrome Cardiopulmonar por Hantavírus (HCPS) é uma doença emergente, causada pelo gênero hantavírus membro da família Bunyaviridae, e são transmitidos aos humanos por aerossol de roedores infectados. O objetivo principal deste estudo foi determinar os níveis de anticorpos para hantavírus em uma população de residentes na fronteira do Brasil com a Argentina. Participaram deste estudo 405 indivíduos que moravam nos municípios de Bandeirante, Santa Helena, Princesa e Tunapólis, no estado de Santa Catarina, Brasil. Os anticorpos IgG para hantavírus foram analisados no soro por um ELISA que usa a nucleoproteína recombinante do vírus Araraquara como antígeno, posteriormente confirmados por imunofluorescência. Oito indivíduos apresentavam anticorpos para hantavírus (1.97% positivo), com titulo entre 100 a 800. Seis soropositivos foram homens, com idade superior a 30 anos e agricultores. Nossos resultados reforçam a circulação do hantavírus e infecção humana na fronteira do Brasil com a Argentina