Papers by Wanessa Ramsdorf
Os medicamentos anti-hipertensivos estao entre os farmacos mais encontrados na natureza. O intere... more Os medicamentos anti-hipertensivos estao entre os farmacos mais encontrados na natureza. O interesse em conhecer os efeitos que essas substâncias podem causar em organismos aquaticos de relevância ecologica aumenta gradualmente. A Losartana potassica e o principal representante dessa classe de medicamentos, sendo o farmaco mais consumido no Brasil nos ultimos anos e encontrado em corpos d’agua em concentracoes na faixa de ng·L -1 e μg·L -1 . O objetivo deste trabalho foi avaliar os efeitos da losartana potassica em organismos aquaticos de dois niveis troficos diferentes, utilizando bioensaios cronicos com Desmodesmus subspicatus , conforme a ABNT NBR 12648:2011, e bioensaio agudo com Daphnia magna , conforme a ABNT NBR 12713:2016. No ensaio com D. subspicatus , o valor preliminar obtido de CEO 50 foi de 29,2 μg·L -1 . Para D. magna , o valor definitivo de CE 50 encontrado foi de 303.689,0 μg·L -1 . Verificamos assim, maior sensibilidade de D. subspicatus ao farmaco pesquisado. Com o...
Bookmarks Related papers MentionsView impact
Fish physiology and biochemistry, Jan 7, 2017
Cylindrospermopsin (CYN) is a cyanotoxin that is cytotoxic to a wide variety of cells, particular... more Cylindrospermopsin (CYN) is a cyanotoxin that is cytotoxic to a wide variety of cells, particularly to the hepatocytes. In this study, the toxic effects of purified CYN were investigated in primary cultured hepatocytes of Neotropical fish Hoplias malabaricus. After isolation, attachment, and recovery for 72 h, the cells were exposed for 72 h to 0, 0.1, 1.0, 10, and 100 μg l(-1) of CYN. Then, cell viability and a set of oxidative stress biomarker responses were determined. Catalase, superoxide dismutase, glucose-6-phosphate dehydrogenase, and glutathione S-transferase activities were not affected by exposure to CYN. Concentration-dependent decrease of glutathione reductase activity occurred for most CYN-exposed groups, whereas non-protein thiol content increased only for the highest CYN concentration. Lipid peroxidation, protein carbonylation, and DNA damage levels were not altered, but reactive oxygen species levels increased in the cells exposed to the highest concentration of CYN....
Bookmarks Related papers MentionsView impact
Toxicology in Vitro, 2011
Bookmarks Related papers MentionsView impact
Herbicide mixture is used as an alternative to obtain different mechanisms of action acting on we... more Herbicide mixture is used as an alternative to obtain different mechanisms of action acting on weeds, resulting in the frequent presence of pesticides in environmental compartments. As they are products used worldwide, this study evaluated effects of environmentally relevant concentrations of the analytical standards and commercial formulations of the herbicides atrazine (2 µg L− 1) and glyphosate (65 µg L− 1), in isolation and also in mixture (2 + 65 µg L− 1) on the microcrustacean Daphnia magna. Through chronic exposure (21 days) of two generations of organisms, effects on survival and reproductive capacity were observed, as well as responses regarding oxidative stress, determined through the analysis of biochemical biomarkers such as catalase and glutathione S-transferase. In the evaluation of the first generation of test organisms, no significant results related to biochemical biomarkers were observed, only effects over sexual maturation of organisms. However, in the second gene...
Bookmarks Related papers MentionsView impact
Coleção desafios das engenharias: Engenharia sanitária 2
Bookmarks Related papers MentionsView impact
Environmental Toxicology and Pharmacology
Bookmarks Related papers MentionsView impact
Environmental Toxicology and Pharmacology
Bookmarks Related papers MentionsView impact
Biocatalysis and Biotransformation
Bookmarks Related papers MentionsView impact
Environmental Science and Pollution Research
Bookmarks Related papers MentionsView impact
Environmental Monitoring and Assessment
Bookmarks Related papers MentionsView impact
Eclética Química Journal
Since 2008, Brazil has been the largest consumer of agrochemicals in the world, using pesticides ... more Since 2008, Brazil has been the largest consumer of agrochemicals in the world, using pesticides to combat pests and vectors, impacting both microbiota and human health. Aiming at the degradation of the contaminants present in the environment, treatments by advanced oxidative processes are based on the synthesis of free radicals that allow the degradation of the pollutant. Among these processes are included UV/H2O2. By evaluating the ecotoxicity and phytotoxicity of the commercial Malathion® 500 CE product, using Aedes aegypti larvae and Lactuca sativa seed, the high toxicity of this formulation was observed. EC50 values for A. aegypti being equal to 0.4 μg L-1 and for L. sativa equal to 550 μg L-1. The commercial agrochemical degradation was carried out by UVC radiation and UV/H2O2, and the toxicity was evaluated after 30 and 120 minutes. After both treatments, the percentage of immobility was zero for A. aegypti, inferring the efficiency of the processes. However, for L. sativa, n...
Bookmarks Related papers MentionsView impact
Ecotoxicology and Environmental Safety
Bookmarks Related papers MentionsView impact
Environmental Toxicology and Pharmacology
Bookmarks Related papers MentionsView impact
Ecotoxicology and Environmental Safety
Bookmarks Related papers MentionsView impact
Aerobiologia
Bookmarks Related papers MentionsView impact
Ecotoxicology and environmental safety, Jan 15, 2018
Carbon Nanotubes are among the most promising materials for the technology industry. Their unique... more Carbon Nanotubes are among the most promising materials for the technology industry. Their unique physical and chemical proprieties may reduce the production costs and improve the efficiency of a large range of products. However, the same characteristics that have made nanomaterials interesting for industry may be responsible for inducing toxic effects on the aquatic organisms. Since the carbon nanotubes toxicity is still a controversial issue, we performed tests of acute and subchronic exposure to a commercial sample of multiwalled carbon nanotubes in two fish species, an exotic model (Danio rerio) and a native one (Astyanax altiparanae). Using the alkaline version of the comet assay on erythrocytes and the piscine micronucleous, also performed on erythrocytes, it was verified that the tested carbon nanotubes sample did not generate apparent genotoxicity by means of single/double DNA strand break or clastogenic/aneugenic effects over any of the species, independently of the exposur...
Bookmarks Related papers MentionsView impact
Estuarine, Coastal and Shelf Science, 2016
Estuaries are dynamic environments, key for the survival of innumerous ecologically or economical... more Estuaries are dynamic environments, key for the survival of innumerous ecologically or economically important fish species. Among these species are Neotropical silversides (Atherinella brasiliensis), which are resident and abundant in Brazilian estuaries and used as a complementary source of income and food for local communities. To better understand silverside populations in Brazil, we evaluated the genetic diversity, structure and demography of fish sampled at six estuaries from the northeastern to the southern coast, using Random Amplified Polymorphic DNA and mitochondrial DNA (D-loop) markers. High haplotype diversities (h ranging from 0.75 to 0.99) were found in all populations except Carapebus, located in Southeast Brazil (h ¼ 0.54). A total of 69 mtDNA haplotypes were found, with Itaparica (Northeast Brazil) and Carapebus presenting only exclusive haplotypes, while some were shared among populations in the South. Strong regional structure was observed, with very high differentiation between Itaparica and Carapebus, as well as among these two populations and the ones from the Southern region (Paranagu a, Conceiç~ ao, Camacho and Patos). Among southern areas, low/moderate structure was detected. Most populations showed unimodal mismatch distributions indicating recent demographic expansion, while Carapebus presented a multimodal distribution characteristic of a stable or bot-tlenecked population. Times since possible population expansion were highest in Itaparica (32,500 ya) and Carapebus (29,540 ya), while in the Southern region longest time was observed at Conceiç~ ao (25,540 ya) and shortest at Patos (9720 ya). In a general manner, haplotype diversities were directly related to times since population expansions; again, Carapebus was the exception, displaying long time since expansion but low diversity, possibly due to a recent bottleneck caused by the isolation and human impacts this lagoon is subject to. Isolation by Distance was significant for Itaparica and Carapebus, and considering the extremely high differentiation of these populations, we suggest that they could be undergoing speciation. To adequately manage and maintain the genetic variability of silversides in Brazilian estuaries, we propose three distinct management units for this species: 1) Itaparica; 2) Carapebus; and 3) Southern Brazil.
Bookmarks Related papers MentionsView impact
Anais do XX Seminário de Iniciação Científica e Tecnológica da UTFPR, 2015
Bookmarks Related papers MentionsView impact
Anais do XX Seminário de Iniciação Científica e Tecnológica da UTFPR, 2015
Bookmarks Related papers MentionsView impact
Anais do XX Seminário de Iniciação Científica e Tecnológica da UTFPR, 2015
Bookmarks Related papers MentionsView impact
Uploads
Papers by Wanessa Ramsdorf