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Remoção de (oo)cistos de protozoários e de estrogenicidade em sistemas combinados de tratamento de esgoto sanitário; Removal microorganisms, (oo)cysts of protozoa and estrogenicity in combined wastewater treatment systems

Silva, Marcos Schaaf Teixeira da
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 08/08/2014 PT
Relevância na Pesquisa
37.69%
Atualmente há um grande interesse em estudos voltados para sistema de tratamento de esgoto sanitário. Isso se deve principalmente pela presença de microrganismos e substâncias que podem interferir na saúde humana e ambiental. Dentre os microrganismos patogênicos responsáveis por transmissão de doenças estão os protozoários Giardia spp. e Cryptosporidium spp. No que se refere às substâncias nocivas à saúde humana e ambiental podem ser citados os desreguladores endócrinos que agem sobre o sistema endócrino de homens e animais causando efeitos adversos. Baseado na importância destes estudos, o presente trabalho teve por objetivo avaliar a eficiência de remoção de protozoários patogênicos - Giardia spp. e Cryptosporidium spp. e da atividade de estrogenicidade em processos de tratamento de esgoto sanitário constituídos por reator UASB, sistema de lodos ativados e filtro de areia. Também foram avaliados os padrões de qualidade dos efluentes do reator UASB e sistema de lodos ativados utilizando sulfato de alumínio e cloreto férrico. A combinação dos processos biológicos sequenciais apresentou robustez em termos de remoção de matéria orgânica, microrganismos indicadores e (oo)cistos. A desinfecção com cloro mostrou-se eficiente em inativar os microrganismos indicadores: coliformes totais e Escherichia coli. A atividade estrogênica...

Estrogenic and chemopreventive activities of xanthones and flavones of Syngonanthus (Eriocaulaceae)

De Oliveira, Ana Paula Siqueira; De Sousa, Juliana Ferreira; Da Silva, Marcelo Aparecido; Hilário, Felipe; Resende, Flávia Aparecida; De Camargo, Mariana Santoro; Vilegas, Wagner; Santos, Lourdes Campaner Dos; Varanda, Eliana Aparecida
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 1053-1063
ENG
Relevância na Pesquisa
27.5%
The possible benefits of some bioactive flavones and xanthones present in plants of the genus Syngonanthus prompted us to screen them for estrogenic activity. However, scientific research has shown that such substances may have undesirable properties, such as mutagenicity, carcinogenicity and toxicity, which restrict their use as therapeutic agents. Hence, the aim of this study was to assess the estrogenicity and mutagenic and antimutagenic properties. We used recombinant yeast assay (RYA), with the strain BY4741 of Saccharomyces cerevisiae, and Ames test, with strains TA100, TA98, TA97a and TA102 of Salmonella typhimirium, to evaluate estrogenicity, mutagenicity and antimutagenicity of methanolic extracts of Syngonanthus dealbatus (S.d.), Syngonanthus macrolepsis (S.m.), Syngonanthus nitens (S.n.) and Syngonanthus suberosus (S.s.), and of 9 compounds isolated from them (1 = luteolin, 2 = mix of A-1,3,6-trihydroxy-2-methoxyxanthone and B-1,3,6-trihydroxy-2,5- dimethoxyxanthone, 3 = 1,5,7-trihydroxy-3,6-dimethoxyxanthone, 4 = 1,3,6,8-tetrahydroxy-2,5-dimethoxyxanthone, 5 = 1,3,6,8-tetrahydroxy-5- methoxyxanthone, 6 = 7-methoxyluteolin-8-C-β-glucopyranoside, 7 = 7-methoxyluteolin-6-C-β-glucopyranoside, 8 = 7,3′-dimethoxyluteolin- 6-C-β-glucopyranoside and 9 = 6-hydroxyluteolin). The results indicated the estrogenic potential of the S. nitens methanol extract and four of its isolated xanthones...

Effect of gamma radiation on the citotoxicity and estrogenicity of Zearalenone

Calado, Thalita; Verde, S. Cabo; Abrunhosa, Luís; Venâncio, Armando; Fernández-Cruz, M.
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em //2015 ENG
Relevância na Pesquisa
27.69%
Zearalenone (ZEA) is a non-steroidal estrogenic mycotoxin produced by several species of Fusarium mostly on cereals and corn. ZEA has a relatively low acute toxicity but it interferes strongly with estrogen receptors and, consequently, with the reproductive tract of individuals. Many methods have been used to eliminate mycotoxins from foods and feeds. Gamma radiation has been also investigated for mycotoxins detoxification showing some promising results. The purpose of present study was to evaluate the cytotoxicity of ZEA degradation products obtained after its irradiation and also to evaluate their estrogenicity. The effect of water during the irradiation process was also evaluated. Vials with 60M of ZEA at distinct moisture levels (dehydrated and in water) were irradiated with 0, 2.0 and 10.0 kGy doses. ZEA levels were determined by HPLC with fluorescence detection. Cytotoxicity of ZEA was assessed in Hep G2 cells using a battery of assays covering different modes of action including alterations of metabolic activity (AlamarBlue assay), plasma membrane integrity (CFDA-AM assay) and lysosomal function (NRU assay). The estrogenicity was assessed in HeLa 9903 cells, measuring luciferase activity. It was observed that gamma radiation is effective in reducing ZEA concentration...

Chemical and biological characterization of estrogenicity in effluents from WWTPs in Ria de Aveiro (NW Portugal)

Sousa, A.; Schönenberger, R.; Jonkers, N.; Suter, M. J. F.; Tanabe, S.; Barroso, C. M.
Fonte: Springer Verlag Publicador: Springer Verlag
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
27.18%
Effluents from wastewater treatment plants (WWTPs) are responsible for the input of estrogenic contaminants into aquatic ecosystems, leading to widespread effects in wildlife. In the present work, levels of estrone (E1), 17α- and 17β-estradiol (E2), 17α-ethinylestradiol (EE2), bisphenol A (BPA), and nonylphenol (NP) were quantified in effluents from WWTPs located in Ria de Aveiro (NW Portugal), as well as in the final effluent discharged into the Atlantic Ocean through the S. Jacinto submarine outfall. Reference sites, located at the entrance of the estuarine system and at the seaside, were also included. Samples were collected under summer (June 2005) and winter (February 2006) conditions. For the summer survey samples, estrogenicity and androgenicity were evaluated using the yeast estrogen screen (YES) and the yeast androgen screen (YAS) assay. Estrone levels varied from 0.5 to 85 ng/L in the summer survey and between

In vitro and in vivo estrogenicity of UV screens.

Schlumpf, M; Cotton, B; Conscience, M; Haller, V; Steinmann, B; Lichtensteiger, W
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /03/2001 EN
Relevância na Pesquisa
27.18%
Ultraviolet (UV) screens are increasingly used as a result of growing concern about UV radiation and skin cancer; they are also added to cosmetics and other products for light stability. Recent data on bioaccumulation in wildlife and humans point to a need for in-depth analyses of systemic toxicology, in particular with respect to reproduction and ontogeny. We examined six frequently used UVA and UVB screens for estrogenicity in vitro and in vivo. In MCF-7 breast cancer cells, five out of six chemicals, that is, benzophenone-3 (Bp-3), homosalate (HMS), 4-methyl-benzylidene camphor (4-MBC), octyl-methoxycinnamate (OMC), and octyl-dimethyl-PABA (OD-PABA), increased cell proliferation with median effective concentrations (EC(50)) values between 1.56 and 3.73 microM, whereas butyl-methoxydibenzoylmethane (B-MDM) was inactive. Further evidence for estrogenic activity was the induction of pS2 protein in MCF-7 cells and the blockade of the proliferative effect of 4-MBC by the estrogen antagonist ICI 182,780. In the uterotrophic assay using immature Long-Evans rats that received the chemicals for 4 days in powdered feed, uterine weight was dose-dependently increased by 4-MBC (ED(50 )309mg/kg/day), OMC (ED(50) 935 mg/kg/day), and weakly by Bp-3 (active at 1...

The mouse uterotrophic assay: a reevaluation of its validity in assessing the estrogenicity of bisphenol A.

Markey, C M; Michaelson, C L; Veson, E C; Sonnenschein, C; Soto, A M
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /01/2001 EN
Relevância na Pesquisa
27.5%
The prevalence of synthetic chemicals in our environment that are capable of mimicking the female hormone estrogen is a growing concern. One such chemical, bisphenol A (BPA), has been shown to leach from a variety of resin-based and plastic products, including dental sealants and food and beverage containers, in concentrations that are sufficient to induce cell proliferation in vitro. The response to BPA in vivo has been varied; thus the aims of this study were to investigate a) whether BPA has an estrogenic effect in CD-1 mice, a strain that is useful for developmental studies; and b) whether the uterotrophic assay is a valid means of determining the estrogenicity of BPA by comparing it with other end points measured in the uterus. Immature female CD-1 mice were exposed to BPA in concentrations ranging from 0.1 to 100 mg/kg body weight for 3 days. Results showed that BPA induced a significant increase in the height of luminal epithelial cells within the uterus at concentrations of 5, 75, and 100 mg/kg and that BPA induced lactoferrin at concentrations of 75 and 100 mg/kg. A uterotrophic response (increase in uterine wet weight) was induced by 100 mg/kg BPA only. Further, the proportion of mice showing vaginal opening was greater after exposure to 0.1 and 100 mg/kg BPA...

Estrogenicity of resin-based composites and sealants used in dentistry.

Olea, N; Pulgar, R; Pérez, P; Olea-Serrano, F; Rivas, A; Novillo-Fertrell, A; Pedraza, V; Soto, A M; Sonnenschein, C
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /03/1996 EN
Relevância na Pesquisa
27.18%
We tested some resin-based composites used in dentistry for their estrogenic activity. A sealant based on bisphenol-A diglycidylether methacrylate (bis-GMA) increased cell yields, progesterone receptor expression, and pS2 secretion in human estrogen-target, serum-sensitive MCF7 breast cancer cells. Estrogenicity was due to bisphenol-A and bisphenol-A dimethacrylate, monomers found in the base paste of the dental sealant and identified by mass spectrometry. Samples of saliva from 18 subjects treated with 50 mg of a bis-GMA-based sealant applied on their molars were collected 1 hr before and after treatment. Bisphenol-A (range 90-931 micrograms) was identified only in saliva collected during a 1-hr period after treatment. The use of bis-GMA-based resins in dentistry, and particularly the use of sealants in children, appears to contribute to human exposure to xenoestrogens.

The estrogenicity of bisphenol A-related diphenylalkanes with various substituents at the central carbon and the hydroxy groups.

Perez, P; Pulgar, R; Olea-Serrano, F; Villalobos, M; Rivas, A; Metzler, M; Pedraza, V; Olea, N
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /03/1998 EN
Relevância na Pesquisa
27.18%
The chemical structure of hydroxylated diphenylalkanes or bisphenols consists of two phenolic rings joined together through a bridging carbon. This class of endocrine disruptors that mimic estrogens is widely used in industry, particularly in plastics. Bisphenol F, bisphenol A, fluorine-containing bisphenol A (bisphenol AF), and other diphenylalkanes were found to be estrogenic in a bioassay with MCF7 human breast cancer cells in culture (E-SCREEN assay). Bisphenols promoted cell proliferation and increased the synthesis and secretion of cell type-specific proteins. When ranked by proliferative potency, the longer the alkyl substituent at the bridging carbon, the lower the concentration needed for maximal cell yield; the most active compound contained two propyl chains at the bridging carbon. Bisphenols with two hydroxyl groups in the para position and an angular configuration are suitable for appropriate hydrogen bonding to the acceptor site of the estrogen receptor. Our data suggest that estrogenicity is influenced not only by the length of the substituents at the bridging carbon but also by their nature. Because diphenylalkane derivatives are widespread and their production and use are increasing, potential exposure of humans to estrogenic bisphenols is becoming a significant issue. The hazardous effects of inadvertent exposure to bisphenol-releasing chemicals in professional workers and the general populations therefore deserve investigation.

Tools to evaluate estrogenic potency of dietary phytoestrogens:A consensus paper from the EU Thematic Network “Phytohealth” (QLKI-2002-2453)

Saarinen, N. M.; Bingham, C.; Lorenzetti, S.; Mortensen, A.; Mäkelä, S.; Penttinen, P.; SØrensen, I. K.; Valsta, L. M.; Virgili, F.; Vollmer, G.; Wärri, A.; Zierau, O.
Fonte: Springer-Verlag Publicador: Springer-Verlag
Tipo: Artigo de Revista Científica
Publicado em /09/2006 EN
Relevância na Pesquisa
17.91%
Phytoestrogens are naturally occurring plantderived polyphenols with estrogenic potency. They are ubiquitous in diet and therefore, generally consumed. Among Europeans, the diet is rich in multiple putative phytoestrogens including flavonoids, tannins, stilbenoids, and lignans. These compounds have been suggested to provide beneficial effects on multiple menopause-related conditions as well as on development of hormone-dependent cancers, which has increased the interest in products and foods with high phytoestrogen content. However, phytoestrogens may as well have adverse estrogenicity related effects similar to any estrogen. Therefore, the assessment of estrogenic potency of dietary compounds is of critical importance. Due to the complex nature of estrogenicity, no single comprehensive test approach is available. Instead, several in vitro and in vivo assays are applied to evaluate estrogenic potency. In vitro estrogen receptor (ER) binding assays provide information on the ability of the compound to I) interact with ERs, II) bind to estrogen responsive element on promoter of the target gene as ligand-ER complex, and III) interact between the co-activator and ERs in ligand-dependent manner. In addition, transactivation assays in cells screen for ligand-induced ERmediated gene activation. Biochemical in vitro analysis can be used to test for possible effects on protein activities and E-screen assays to measure (anti)proliferative response in estrogen responsive cells. However...

Europe-wide survey of estrogenicity in wastewater treatment plant effluents: the need for the effect-based monitoring

JAROSOVA Barbora; ERSEKOVA A.; HILSCHEROVA K.; LOOS Robert; GAWLIK Bernd; GIESY J.p.; BLAHA Ludek
Fonte: SPRINGER HEIDELBERG Publicador: SPRINGER HEIDELBERG
Tipo: Articles in Journals Formato: Printed
ENG
Relevância na Pesquisa
27.5%
A pan-European monitoring campaign of the wastewater treatment plant (WWTP) effluents was conducted to obtain a concise picture on a broad range of pollutants including estrogenic compounds. Snapshot samples from 75 WWTP effluents were collected and analysed for concentrations of 150 polar organic and 20 inorganic compounds as well as estrogenicity using the MVLN reporter gene assay. The effect-based assessment determined estrogenicity in 27 of 75 samples tested with the concentrations ranging from 0.53 to 17.9 ng/L of 17-beta-estradiol equivalents (EEQ). Approximately one third of municipal WWTP effluents contained EEQ greater than 0.5 ng/L EEQ, which confirmed the importance of cities as the major contamination source. Beside municipal WWTPs, some treated industrial wastewaters also exhibited detectable EEQ, indicating the importance to investigate phytoestrogens released from plant processing factories. No steroid estrogens were detected in any of the samples by instrumental methods above their limits of quantification of 10 ng/L, and none of the other analysed classes of chemicals showed correlation with detected EEQs. The study demonstrates the need of effect-based monitoring to assess certain classes of contaminants such as estrogens...

Comparison of shor-term estrogenicity tests for identification of hormone-disrupting chemicals

Andersen, Helle Raun; Andersson, Anna-Maria; Arnold, Steven F.; Autrup, Herman; Barfoed, Marianne; Beresford, Nicola; Bjerregaard, Poul; Christiansen, Lisette; Gissel, Birgitte; Hummel, Ren??; J??rgensen, Eva B.; Korsgaard, Bodil; Guevel, Remy Le; Leffers
Fonte: National Institute of Environmental Health Sciences Publicador: National Institute of Environmental Health Sciences
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
27.18%
The aim of this study was to compare results obtained by eight different short-term assays of estrogenlike actions of chemicals conducted in 10 different laboratories in five countries. Twenty chemicals were selected to represent direct-acting estrogens, compounds with estrogenic metabolites, estrogenic antagonists, and a known cytotoxic agent. Also included in the test panel were 17??-estradiol as a positive control and ethanol as solvent control. The test compounds were coded before distribution. Test methods included direct binding to the estrogen receptor (ER), proliferation of MCF-7 cells, transient reporter gene expression in MCF-7 cells, reporter gene expression in yeast strains stably transfected with the human ER and an estrogen-responsive reporter gene, and vitellogenin production in juvenile rainbow trout. 17??-Estradiol, 17??-ethynyl estradiol, and diethylstilbestrol induced a strong estrogenic response in all test systems. Colchicine caused cytotoxicity only. Bisphenol A induced an estrogenic response in all assays. The results obtained for the remaining test compounds???tamoxifen, ICI 182.780, testosterone, bisphenol A dimethacrylate, 4-n-octylphenol, 4-n-nonylphenol, nonylphenol dodecylethoxylate, butylbenzylphthalate...

Estrogenicity of resin-based composites and sealants used in dentistry

Olea, Nicol??s; Pulgar Encinas, Rosa Mar??a; P??rez, Pilar; Olea Serrano, F??tima; Rivas, A.; Novillo-Fertrell, Arancha; Pedraza Muriel, Vicente; Soto, Ana M.; Sonnenschein, Carlos
Fonte: National Institute of Environmental Health Publicador: National Institute of Environmental Health
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
27.18%
We tested some resin-based composites used in dentistry for their estrogenic activity. A sealant based on bisphenol-A diglycidylether methacrylate (bis-GMA) increased cell yields, progesterone receptor expression, and pS2 secretion in human estrogen-target, serum-sensitive MCF7 breast cancer cells. Estrogenicity was due to bisphenol-A and bisphenol-A dimethacrylate, monomers found in the base paste of the dental sealant and identified by mass spectrometry. Samples of saliva from 18 subjects treated with 50 mg of a bis-GMA-based sealant applied on their molars were collected 1 hr before and after treatment. Bisphenol-A (range 90-931 micrograms) was identified only in saliva collected during a 1-hr period after treatment. The use of bis-GMA-based resins in dentistry, and particularly the use of sealants in children, appears to contribute to human exposure to xenoestrogens.

The estrogenicity of bisphenol A-related diphenylalkanes with various substituents at the central carbon and the hydroxy groups

P??rez, Pilar; Pulgar Encinas, Rosa Mar??a; Olea Serrano, F??tima; Villalobos Torres, Mercedes; Rivas, A.; Metzler, Manfred; Pedraza Muriel, Vicente; Olea, Nicol??s
Fonte: National Institute of Environmental Health Publicador: National Institute of Environmental Health
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
27.18%
This work was reported in part at the meeting Estrogens in the Environment IV: Linking Fundamental Knowledge, Risk Assessment, and Public Policy held in Washington, DC, 19-21 July 1997.; The chemical structure of hydroxylated diphenylalkanes or bisphenols consists of two phenolic rings joined together through a bridging carbon. This class of endocrine disruptors that mimic estrogens is widely used in industry, particularly in plastics. Bisphenol F, bisphenol A, fluorine-containing bisphenol A (bisphenol AF), and other diphenylalkanes were found to be estrogenic in a bioassay with MCF7 human breast cancer cells in culture (E-SCREEN assay). Bisphenols promoted cell proliferation and increased the synthesis and secretion of cell type-specific proteins. When ranked by proliferative potency, the longer the alkyl substituent at the bridging carbon, the lower the concentration needed for maximal cell yield; the most active compound contained two propyl chains at the bridging carbon. Bisphenols with two hydroxyl groups in the para position and an angular configuration are suitable for appropriate hydrogen bonding to the acceptor site of the estrogen receptor. Our data suggest that estrogenicity is influenced not only by the length of the substituents at the bridging carbon but also by their nature. Because diphenylalkane derivatives are widespread and their production and use are increasing...

Dual effects of phytoestrogens result in u-shaped dose-response curves

Almstrup, Kristian; Fern??ndez, Mariana F.; Petersen, J??rgen; Olea, Nicol??s; Skakkeb??k, Niels; Leffers, Henrik
Fonte: National Institute of Environmental Health Sciences Publicador: National Institute of Environmental Health Sciences
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
27.5%
'Reproduced with permission from Environmental Health Perspectives'; Endocrine disruptors can affect the endocrine system without directly interacting with receptors, for example, by interfering with the synthesis or metabolism of steroid hormones. The aromatase that converts testosterone to 17??-estradiol is a possible target. In this paper we describe an assay that simultaneously detects aromatase inhibition and estrogenicity. The principle is similar to that of other MCF-7 estrogenicity assays, but with a fixed amount of testosterone added. The endogenous aromatase activity in MCF-7 cells converts some of the testosterone to 17??-estradiol, which is assayed by quantifying differences in the expression level of the estrogen-induced pS2 mRNA. Potential aromatase inhibitors can be identified by a dose-dependent reduction in the pS2 mRNA expression level after exposure to testosterone and the test compound. Using this assay, we have investigated several compounds, including synthetic chemicals and phytoestrogens, for aromatase inhibition. The phytoestrogens, except genistein, were aromatase inhibitors at low concentrations (< 1 ??M) but estrogenic at higher concentrations (??? 1 ??M), resulting in U-shaped dose???response curves. None of the tested synthetic chemicals were aromatase inhibitors. The lowdose aromatase inhibition distinguished phytoestrogens from other estrogenic compounds and may partly explain reports about antiestrogenic properties of phytoestrogens. Aromatase inhibition may play an important role in the protective effects of phytoestrogens against breast cancer.

COMPONENTS OF OILS SANDS PROCESS WATER INVOLVED IN TOXICITY, ESTROGENICITY AND BIODEGRADATION

Yue, SIQING
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
37.82%
To process one m3 of oil sands, four m3 of oil sands process wastewater (OSPW) is produced. OSPW is a mixture of compounds including hundreds of different naphthenic acids (NAs) which are considered to the major toxicity contributor of OSPW. Effect-directed analysis was used to establish the link between toxicity/estrogenicity and components in OSPW. OSPW and biologically treated OSPW were separated by solid phase extraction and reverse phase HPLC into “toxic and nontoxic” or “estrogenic and nonestrogenic” fractions as detected by the Microtox® and a yeast estrogenic screening assay respectively. The composition of fractions was determined by ultrahigh resolution mass spectrometry. Multivariate statistical methods were used to analyze the relationship between composition and toxicity/estrogenicity. C15-C18 O2-NAs (CnH2n+zO2) with a double bond equivalent (DBE) of 4, as well as C14-C17 with DBE=3 were found to be the most likely contributors to toxicity, while O2 (CnH2n+zO2), O3 (CnH2n+zO3) and O4 (CnH2n+zO4) C17 to C20 compounds with a DBE 6-10 likely cause estrogenicity. From these studies, the exact formulae and masses of possible estrogenic/toxic compounds in OSPW were identified. These findings will help to focus study on the most environmentally significant components in OSPW. In an earlier published study...

Cloração de água com 17\'beta\'-estradiol e utilização do teste YES para avaliação de estrogenicidade; Chlorination of water with 17\'beta\'-estradiol and application of the YES test for estrogenicity assessment

Fischer, Natália
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 02/07/2013 PT
Relevância na Pesquisa
37.5%
Recentemente, a identificação de substâncias consideradas desreguladores endócrinos em meios aquáticos e a associação destas substâncias com alterações nas comunidades aquáticas, como dificuldades de reprodução em populações de peixes, mostra a importância da pesquisa de tratamentos mais eficientes para a remoção destas substância, bem como uma compreensão maior dos mecanismos de sua oxidação. Dentre estas substâncias de interesse, destacam-se alguns fármacos e hormônios naturais e sintéticos, como é o caso do 17\'beta\'-estradiol. A oxidação com cloro é uma alternativa eficiente para a remoção destas substâncias, mas a formação de subprodutos da oxidação gera preocupações quanto ao risco destes compostos continuarem a apresentar atividade estrogênica, e portanto riscos à comunidade aquática. A proposta desta pesquisa é estudar a oxidação com cloro do 17\'beta\'-estradiol em água de abastecimento, com foco na avaliação da remoção da estrogenicidade utilizando o teste YES. A escolha pela cloração foi feita visto que este é o tratamento mais difundido no Brasil, assim as concentrações e tempos de contato estudados também foram definidos de forma a corresponder àqueles utilizados regularmente em Estações de Tratamento de Água.; In the past years...

Assessing environmental chemicals for estrogenicity using a combination of in vitro and in vivo assays.

Shelby, M D; Newbold, R R; Tully, D B; Chae, K; Davis, V L
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /12/1996 EN
Relevância na Pesquisa
27.18%
Because of rampant concern that estrogenic chemicals in the environment may be adversely affecting the health of humans and wildlife, reliable methods for detecting and characterizing estrogenic chemicals are needed. It is important that general agreement be reached on which tests to use and that these tests then be applied to the testing of both man-made and naturally occurring chemicals. As a step toward developing a comprehensive approach to screening chemicals for estrogenic activity, three assays for detecting estrogenicity were conducted on 10 chemicals with known or suspected estrogenic activity. The assays were 1) competitive binding with the mouse uterine estrogen receptor, 2) transcriptional activation in HeLa cells transfected with plasmids containing an estrogen receptor and a response element, and 3) the uterotropic assay in mice. The chemicals studied were 17 beta-estradiol, diethylstilbestrol, tamoxifen, 4-hydroxytamoxifen, methoxychlor, the methoxychlor metabolite 2,2-bis(p-hydroxyphenyl)-1,1,1-trichloroethane (HPTE), endosulfan, nonylphenol, o,p'-DDT, and kepone. These studies were conducted to assess the utility of this three-assay combination in the routine screening of chemicals, or combinations of chemicals, for estrogenic activity. Results were consistent among the three assays with respect to what is known about the estrogenic activities of the chemicals tested and their requirements for metabolic activation. By providing information on three levels of hormonal activity (receptor binding...

The immature mouse is a suitable model for detection of estrogenicity in the uterotropic bioassay.

Padilla-Banks, E; Jefferson, W N; Newbold, R R
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /08/2001 EN
Relevância na Pesquisa
27.18%
The traditional rodent uterotropic response assay has been incorporated into the U.S. Environmental Protection Agency's screening and testing program for environmental endocrine-disrupting chemicals (EDCs). While much effort continues to focus on determining protocol variables, few studies compare uterotropic responses in rats, a species commonly used in toxicologic testing, with other rodent species. In this study, we compared uterine responses in immature outbred CD-1 mice and Sprague-Dawley rats. After three daily subcutaneous injections with 17beta-estradiol (0.1-500 microg/kg/day), immature mice and rats demonstrated a similar dose-response increase in absolute uterine wet weight and uterine weight:body weight ratio. Further, morphologic and biochemical parameters of estrogenicity, including uterine epithelial cell height and number, gland number, and induction of estrogen-responsive proteins lactoferrin and complement C3, mirror wet weight increases. We conclude that mice are as well suited as rats for the uterotropic bioassay. Because of the advantages of using mice, including lower costs, less space required, and smaller amounts of compound needed for tests, mice should be given appropriate consideration in testing paradigms for EDCs.

Distribution of endocrine disruptors in the Llobregat River basin (Catalonia, NE Spain)

Céspedes, Raquel; Lacorte Bruguera, Silvia; Raldúa, Demetrio; Ginebreda Martí, Antoni; Barceló, Damià; Piña, Benjamín
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 22195 bytes; application/pdf
ENG
Relevância na Pesquisa
27.18%
10 pages, 3 figures.-- PMID: 15893793 [PubMed].-- Printed version published Dec 2005.; The Llobregat basin is a Mediterranean fluvial system with major agricultural, urban and industrial impacts. We combined chemical quantification by liquid chromatography–mass spectrometry with electrospray interface (LC-ESI-MS) and the recombinant yeast assay (RYA) assays to estimate the loads of endocrine disrupting compounds (EDCs) along the basin. Chemical analysis revealed maximum concentrations (at μg l−1 level) of alkylphenols at the lower course of the Llobregat River, which correlated with high levels of estrogenic activity detected by RYA. Analysis by RYA and LC-ESI-MS of influent and effluent waters from four sewage treatment plants (STP) discharging into the basin showed the removal of 80–95% of EDCs by STP treatment. Chemical analysis data and RYA data showed a quasi-linear correlation, demonstrating the complementariness of both methods. Our data suggest that the concentrations of the analysed compounds were enough to explain the total estrogenicity of water and STP samples from the Llobregat basin.; This work was supported by the Catalan Water Agency contract and by the Ministerio de Ciencia y Tecnología (Spain) project BQU2002-10315-E...

Integrated procedure for determination of endocrine-disrupting activity in surface waters and sediments by use of the biological technique recombinant yeast assay and chemical analysis by LC-ESI-MS

Céspedes, Raquel; Petrovic, Mira; Raldúa, Demetrio; Saura, Úrsula; Piña, Benjamín; Lacorte Bruguera, Silvia; Viana, Paula; Barceló, Damià
Fonte: Springer Publicador: Springer
Tipo: Artículo Formato: 22195 bytes; application/pdf
ENG
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12 pages, 5 figures, 4 tables.-- PMID: 14658021 [PubMed].-- Available online Dec 5, 2003.; An integrated procedure using mass spectrometry and molecular biology for determination of estrogenicity in natural waters and sediments is reported. Solid-phase extraction (SPE) and pressurized-liquid extraction (PLE), respectively, were used for isolation of endocrine-disrupting compounds (EDC) from surface waters and sediments, followed by liquid chromatography–mass spectrometry using an electrospray interface (LC–ESI-MS). Twenty seven EDC were determined: non-ionic surfactants (nonylphenol ethoxylate), alkylphenols (e.g. nonylphenol and octylphenol), bisphenol A, phthalates, and natural and synthetic steroid sex hormones. Limits of detection varied from 0.02 to 0.22 μg L–1 and from 1 to 10 μg kg–1 in water and sediments, respectively. Recoveries ranged from 65 to 125% and 73 to 97% for waters and sediments, respectively. In addition to LC–ESI-MS determination, extracts obtained by SPE and PLE were analyzed by the recombinant yeast assay (RYA) to assess total estrogenic activity. This bioassay detects natural estrogens and xenoestrogens, producing a quantitative measurement of EDC irrespective of the identity of the chemical responsible for the activity. As a novelty...