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Iron oxide nanoparticles (IONP) are promising alternatives to environmental remediation, so this study investigates IONP single and associated to contaminants, in this case, glyphosate (GLY) and Roundup® (GBH) in Poecilia reticulata (guppy). The guppies have internal development, therefore this study analyzed female gonads to establish the developmental stages of P. reticulata and evaluate effects of exposure (7, 14 and 21 days) and post-exposure (same period) to the treatments with Iron ions 0.3 mg Fe/L (IFe); IONP 0.3 mg Fe/L; IONP 0.3 mgFe/L + GBH 0,65 mgGLY/L (IONP+GBH1); IONP 0.3 mgFe/L + GBH 1.30 mgGLY/L (IONP+GBH2); and IONP 0.3 mgFe/L + GLY 0.65 mg/L (IONP+GLY). The development was organized in immature, development, and gestation phases. The damage in all treatments after 21 days of exposure was evident in reaction patterns regressive inflammatory, and circulatory including total histopathologic index of liver, nevertheless there was a damage recovery trend during post-exposure period.

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Domperidone is a dopamine D2 receptor inhibitor that stimulates pituitary gonadotropins. It is usually associated with synthetic GnRHa to promote spawning in fish. However, the route of administration used, intramuscular injection, can be quite stressful. Little is known about the effects of domperidone, as well as other routes. This study aims to evaluate the toxicity of domperidone encapsulated by silica nanoparticles in zebrafish embryos. The study involved four groups with three concentrations: 1. domperidone (DP) 0.0001, 0.0002 and 0.0004 mg/mL; 2. DP associated with silica nanoparticles (SiNPs) 0.0001 + 1.1, 0.0002 + 2.2 and 0.0004 + 4.4 mg/mL; 3. SiNPs 1.1, 2.2 and 4.4 mg/mL and 4. Control (E3), with four repetitions per group. Survival, teratogen and heart rate (HR) were evaluated over a period of 168 hpf. Survival was higher in DP + SiNPs treatment, HR was lower in treatment with 4.4 mg/mL of SiNPs, while treatment with 0.004 mg/mL of DP increased HR. This study demonstrated that the association of DP and SiNPs decreased the toxicity of both DP and SiNPs, demonstrating that this may be a viable alternative to reduce the possible cardiotoxic effects of DP.

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Toxicity evaluations involve the analysis of multiple biomarkers. In this study, the liver, target organ analyzed by treatments with iron concentrations, indicated the accumulation of lipids as a response. Considering that the distribution of lipids in an organ is directly related to the induction of inflammatory processes by aquatic contaminants, this study proposes to carry out an integrative investigation of the behavior and the distribution of lipids in the liver tissue. Techniques of light and electron microscopy were performed in order to propose a new way of assessing and quantifying the distribution of lipid droplets, also presenting methodological alternatives that can be chosen by the reader according to the interests and resources available. Thus, it is assumed that the method begins with the fixation of the liver with Glutaraldehyde 2,5% in PBS 0,1 M and continues with post fixation with osmium tretoxide 1%, which marks lipids. For this proposition, two inclusion methodologies were performed to histological analyses in Historesin and ultrastructural analyses in EMBeed 812. For light microscopy (LM) analyses, cuts were obtained with 2,5 micrometers thickness, which were stained with (1) Mayers hematoxylin and (2) toluidine blue. The images obtained were processed in software Image J Fiji to evidence the lipid distribution in liver.•Cytological reactions with osmium tetroxide constitute low complexity methods that allow the optimization of the localization, identification and quantification of lipid droplets in the liver tissue when analyzed under the conventional light microscope.•Samples included in EMBeed 812 resin commonly used in Transmission Electron Microscopy can be analyzed by SEM-BEC, as complementary analyses for the detection of lipids.•Using SEM-BEC and conventional light microscopy, it is possible to quantify the area occupied by lipid droplets using Image J Fiji software, as these are contrasted due to the reaction with osmium tetroxide.

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Citrate functionalized iron oxide nanoparticles (IONPs) are employed for various purposes-including environmental remediation but the interaction of IONPs with aquatic contaminants is poorly understood. Among those, glyphosate-based herbicides are toxic and affect target organs such as the liver. Evaluations of livers of female Poecilia reticulata by exposures to IONPs at a concentration of 0.3 mg/L were performed with association to: (1) 0.65 mg of glyphosate per litter and (2) 1.3 mg of glyphosate per litter of Roundup Original, and (3) glyphosate P.A at 0.65 mg/L. These associations were carried out progressively, after 7, 14, and 21 days. We detected circulatory disturbances, inflammatory responses, activation of the immune system, regressive changes, and progressive responses with changes in the connective tissue and decreased glycogen reserve from days 14 to 21. Ultrastructural changes in the Disse space and microvilli of hepatocytes indicated decreased contact surface area. In general, the damage was time and concentration dependent, increasing from 7 to 14 days and tending to stabilize from 14 to 21 days. Therefore, herbicide-associated IONPs functioned as xenobiotics inducing intense cellular detoxification processes and activation of hepatic immune responses.

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Citrate-coated iron oxide nanoparticles (IONPs) have potential use in environmental remediation, with possibilities in decontaminating aquatic environments exposed to toxic substances. This study analyzed IONPs associated to Roundup Original, a glyphosate-based herbicide (GBH), and pure glyphosate (GLY), through ultrastructural and histopathological biomarkers in liver tissue, from females of Poecilia reticulata exposed to: iron ions (0.3 mg/L) (IFe) and IONPs (0.3 mgFe/L) associated with GLY (0.65 mg/L) and GBH (0.65 mgGLY/L (IONP + GBH1) and 1.30 mgGLY/L (IONP + GBH2)) for a period of 7, 14 and 21 days, followed by an equal post-exposure period only in reconstituted water. For the assays, the synthetized IONPs had crystalline and rounded shape with an average diameter of 2,90 nm, hydrodynamic diameter 66,6 mV, zeta potential -55,4 and diffraction profile of maghemite (γ-Fe2O3). The data obtained by biomarkers indicated a high inflammatory response in all treatments. These same parameters, considered during the post-exposure period indicated recovery in reaction patterns of circulatory disturbances and regressive changes, resulting in average reductions of 37,53 points in IFe, 21 points in IONP + GBH1, 15 points in IONP + GBH2 and 11 points in IONP + GLY in total histopathological index of liver after 21 days post-exposure. However, although the cellular and tissue responses were significant, there was no change in the condition factor and hepatosomatic index, denoting resilience of the experimental model.

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The purpose of this research was to study the histology and describe the microscopy findings of the epididymis epithelium of greater Rhea americana at three time periods: November 2005 (n=14), December 2006 (n= 20), and May 2007 (n= 20), to observe and compare the differences that occurred. We studied the epididymis from 54 rheas, bred in Santa Maria, Rio Grande do Sul, Brazil. The epididymis were collected during commercial slaughter and fixed in bouin. Optical microscopy was used to measure the cellular structure, types of cells, tubules, and stereological values like the epididymis epithelium diameters, lumen, thickness, and relative volume of the tissue structure. Additionally, electron microscopy was studied. In December 2006 and May 2007, the means of the epididymis tubular diameter were: 79.1 and 58.1 µm, epithelium thickness: 24.0 and 52.2 µm, and lumen diameter: 55.0 and 5.8 µm, respectively. Regarding the volumetric proportion, we reported the following values: epithelium volume 36.2 and 80.4%, lumen without spermatozoon 19.6 and 3.0%, lumen with spermatozoon 5.4 and 0.0%, interstitium 35.4 and 12.0%, blood vessels 3.5 and 4.6%, structures in cellular superficies 1.4 and 0%, lamina 1.4 and 3.2%, and artifacts 0.3 and 1.3%, respectively. The epididymis ducts had a circular form in transverse sections with spermatozoon only in November 2005 and December 2006. The Rheas epididymis morphology was found to be similar to ostriches, roosters, and Japanese quail. Here, we present data from stereological microscopy (tubular diameter, epithelium thickness, and lumen diameter), volumetric proportion (epithelium, lumen without spermatozoon, lumen with spermatozoon, interstitium, blood vessels, structures in cellular superficies; cilium, estereocilium, and lamina) in this species during the repose and sexual activity period (reproductive season).(AU)

O objetivo desta pesquisa foi estudar a histologia e descrever os achados microscópicos do epitélio epidídimo de ema em três períodos: novembro/2005 (n = 14), dezembro/2006 (n = 20) e maio/2007 (n = 20), para observação e comparação das diferenças que ocorreram nesses tempos distintos. Estudamos o epidídimo de 54 animais, criados em Santa Maria, RS. Durante o abate comercial, os epidídimos foram coletados e fixados em Bouin. A microscopia óptica mede a estrutura celular, tipos de células, túbulos e valores estereológicos, como os diâmetros do epitélio do epidídimo, lúmen, espessura, volume relativo da estrutura do tecido. Em dezembro/2006 e maio/2007, as médias do diâmetro tubular do epidídimo foram: 79,1 e 58,1µm, espessura do epitélio: 24,0 e 52,2µm, diâmetro do lúmen: 55,0 e 5,8µm, respectivamente. Em relação à proporção volumétrica, encontramos os seguintes valores: volume epitelial 36,2 e 80,4%, lúmen sem espermatozoide 19,6 e 3,0%, lúmen com espermatozoide 5,4 e 0,0%, intestínio 35,4 e 12,0%, vasos sanguíneos 3,5 e 4,6%, estruturas celulares superfícies 1,4 e 0%, lâmina 1,4 e 3,2%, artefatos 0,3 e 1,3%, respectivamente. Os ductos do epidídimo apresentaram forma circular em cortes transversais com espermatozoide apenas em novembro/2005 e dezembro/2006. A morfologia do epidídimo de Rhea foi semelhante ao avestruz, galo e codornas japonesas. Apresentamos dados de microscopia estereológica (diâmetro tubular, espessura do epitélio, diâmetro do lúmen), proporção volumétrica, em porcentagem (epitélio, lúmen sem espermatozóide, lúmen com espermatozoide, intestório, vasos sanguíneos, estruturas em superfícies celulares - cílio - estereocílio, lâmina e artefatos) nesta espécie nos períodos de repouso e atividade sexual (estação reprodutiva).(AU)

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The organic UV filter benzophenone-3 (BP-3), widely used in the commercial formulations of sunscreens and personal care products, is considered an emerging pollutant and has been associated with several human and environmental health concerns. However, knowledge about their mode of action and ecotoxicity on aquatic biota is scarce. In this scenario, the objective of this work was to evaluate the genotoxic, mutagenic, and erythrotoxicity effects of BP-3 in the guppy Poecilia reticulata after acute exposure. Adult females of P. reticulata were exposed to three non-lethal and environmentally relevant concentrations of BP-3 (10, 100, and 1000 ng L-1) during 96 h of exposure, and the somatic parameter [Fulton condition factor (K)], genotoxicity (comet assay), mutagenicity [micronucleus (MN) and erythrocyte nuclear abnormalities (ENA) tests] and erythrotoxicity parameters (such as total cell area and nucleus-cytoplasmic ratio) were analyzed. Results showed that the general physiological condition (K value) of fish was not affected by acute exposure to BP-3. However, BP-3 induced DNA damage at 100 and 1000 ng L-1 and increased the frequency of total ENA at 1000 ng L-1, specially lobed nucleus, when compared to control group, indicating its genotoxic and mutagenic effects. Furthermore, the BP-3 did not induce significant changes in the total cell area and nucleus-cytoplasmic ratio. In summary, results showed that the BP-3 at environmentally relevant concentration was genotoxic to freshwater fish P. reticulata, confirming its environmental risk.

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Neolignans are secondary metabolites found in various groups of Angiosperms. They belong to a class of natural compounds with great diversity of chemical structures and pharmacological activities. These compounds are formed by linking two phenylpropanoid units. Several compounds that have ability to prevent genetic damage have been isolated from plants, and can be used to prevent or delay the development of tumor cells. Genetic toxicology evaluation is widely used in risk assessment of new drugs in preclinical screening tests. In this study, we evaluated the genotoxicity and cytotoxicity of the neolignan analogue 2-(4-nitrophenoxy)-1-phenylethanone (4NF) and its protective effect against DNA damage using the mouse bone marrow micronucleus test and the comet assay in mouse peripheral blood. Our results showed that this neolignan analogue had no genotoxic activity and was able to reduce induced damage both in mouse bone marrow and peripheral blood. Although the neolignan analogue 4NF was cytotoxic, it reduced cyclophosphamide-induced cytotoxicity. In conclusion, it showed no genotoxic action, but exhibited cytotoxic, antigenotoxic, and anticytotoxic activities.

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Poecilia vivipara (guaru), peixe neotropical de pequeno porte, eurialino, tem sido usado como biomonitor. Analisou-se a musculatura dorsal e ventral do guaru, a fim de se padronizar metodologias para avaliação da estrutura normal deste tecido, com a perspectiva de que sejam usados em estudos de toxicidade. Para tanto, realizaram-se fixações químicas e físicas, que visaram procedimentos histológicos e histoquímicos de coloração e reação. Os métodos H.E. e TM evidenciaram a organização das FMEE, com feixes musculares epiaxial e hipaxial e conjuntivo associado. O AM marcou as FMEE e facilitou a observação dos sarcômeros com a presença de uma fina faixa corada metacromaticamente. Parte das FMEE foi PAS positiva e amilase reativa, indicando a distribuição de glicogênio entre as fibras. Na presença do SBB, as fibras foram reativas, principalmente na região dorsal, indicando a presença de lipídeos. Na SDH pH 10,5 detectou-se presença de células com citoplasma rico em enzimas mitocondriais. As FMEE coradas com AT apresentaram-se organizadas em faixas transversais alternadas, que correspondem ao padrão visualizado ao MET. O uso destas metodologias permitiu indicar a musculatura do guaru como um instrumento para estudos de variações ambientais, visto que sua estrutura normal é padrão nos teleósteos.

Poecilia vivipara (guaru), a neotropical, small, euryhaline fish, has been being used as a biomonitor. Dorsal and ventral muscles of Poecilia vivipara were analyzed to standardize methodologies for evaluating the normal tissue structure, in order to use them in toxicity studies. Thus, chemical and physical fixations were carried out, aiming at the histological and histochemical procedures of staining and reaction. The methods HE and MT revealed the organization of SSMF with epiaxial and hypaxial muscle bundles and associated conjunctive. MA marked the SSMF and facilitated the observation of sarcomeres in the presence of a thin metacromatically stained band. Part of the SSMF was positive PAS and reactive amylase, indicating the distribution of glycogen within the fibers. In the presence of SBB the fibers were reactive mainly in the dorsal region, indicating the presence of lipids. Cells with mitochondrial enzyme-rich cytoplasm were found in SDH pH 10.5. The SSMF stained with AT were arranged in alternating transverse bands, which correspond to the pattern seen under the MET. The use of these methodologies allowed the indication of Poecilia vivipara muscles as a tool for environmental variations studies, because its normal structure is standard in teleosts.

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Poecilia vivipara (guaru), peixe neotropical de pequeno porte, eurialino, tem sido usado como biomonitor. Analisou-se a musculatura dorsal e ventral do guaru, a fim de se padronizar metodologias para avaliação da estrutura normal deste tecido, com a perspectiva de que sejam usados em estudos de toxicidade. Para tanto, realizaram-se fixações químicas e físicas, que visaram procedimentos histológicos e histoquímicos de coloração e reação. Os métodos H.E. e TM evidenciaram a organização das FMEE, com feixes musculares epiaxial e hipaxial e conjuntivo associado. O AM marcou as FMEE e facilitou a observação dos sarcômeros com a presença de uma fina faixa corada metacromaticamente. Parte das FMEE foi PAS positiva e amilase reativa, indicando a distribuição de glicogênio entre as fibras. Na presença do SBB, as fibras foram reativas, principalmente na região dorsal, indicando a presença de lipídeos. Na SDH pH 10,5 detectou-se presença de células com citoplasma rico em enzimas mitocondriais. As FMEE coradas com AT apresentaram-se organizadas em faixas transversais alternadas, que correspondem ao padrão visualizado ao MET. O uso destas metodologias permitiu indicar a musculatura do guaru como um instrumento para estudos de variações ambientais, visto que sua estrutura normal é padrão nos teleósteos.(AU)

Poecilia vivipara (guaru), a neotropical, small, euryhaline fish, has been being used as a biomonitor. Dorsal and ventral muscles of Poecilia vivipara were analyzed to standardize methodologies for evaluating the normal tissue structure, in order to use them in toxicity studies. Thus, chemical and physical fixations were carried out, aiming at the histological and histochemical procedures of staining and reaction. The methods HE and MT revealed the organization of SSMF with epiaxial and hypaxial muscle bundles and associated conjunctive. MA marked the SSMF and facilitated the observation of sarcomeres in the presence of a thin metacromatically stained band. Part of the SSMF was positive PAS and reactive amylase, indicating the distribution of glycogen within the fibers. In the presence of SBB the fibers were reactive mainly in the dorsal region, indicating the presence of lipids. Cells with mitochondrial enzyme-rich cytoplasm were found in SDH pH 10.5. The SSMF stained with AT were arranged in alternating transverse bands, which correspond to the pattern seen under the MET. The use of these methodologies allowed the indication of Poecilia vivipara muscles as a tool for environmental variations studies, because its normal structure is standard in teleosts.(AU)

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O Cerrado brasileiro tem sido um dos domínios ecológicos mais explorado cientificamente nos dias atuais e na última década. Estudos recentes têm proposto o uso de extrato da folha e casca do caule de C. brasiliensis (pequi) como agente moluscicida, no intuito de combater o hospedeiro intermediário (Biomphalaria glabrata) do parasito causador da esquistossomose: Schistosoma mansoni. Como este molusco sempre está próximo a mananciais de água, questiona-se o impacto deste produto sobre a fauna aquática. Neste sentido, utilizamos a brânquia do peixe eurialino Poecilia vivipara (guaru), já bastante utilizado como bioindicador de poluição aquática, para testar a toxicidade de frações de extratos da folha e casca de caule de pequi. Um conjunto de 30 guarus adultos arranjados em 5 grupos experimentais foram expostos a frações aquosa, acetato de etila e etérea da folha e frações aquosa e acetato de etila da casca de caule de pequi, durante 24 horas. Mensurou-se a área e o perímetro dos filamentos branquiais nas regiões: basal, intermediária e apical. As análises estatísticas demonstraram que a área dos grupos experimentais não difere do controle. Porém, o perímetro das regiões basal e intermediária se diferenciaram significativamente do controle o que, todavia, não promoveu o comprometimento das atividades fisiológicas da brânquia. Assim, sugere-se que nas concentrações de 20 ppm, os extratos testados possam ser utilizados como moluscicidas em mananciais aquáticos, excetuando-se a fração aquosa da folha por ser letal nesta concentração

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