Дисертації з теми "Estrogenic endocrine disruptors"
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Swart, Johannes Cornelius. "The development and implementation of biomarker assays for estrogenic endocrine disruptors." Thesis, University of the Western Cape, 2008. http://etd.uwc.ac.za/index.php?module=etd&action=viewtitle&id=gen8Srv25Nme4_6792_1258011445.
Повний текст джерела'Endocrine disrupting chemicals (EDCs) are compounds found in the environment that have the potential to disrupt normal endocrine function. Estrogenic EDCs (e-EDCs) is a subclass of EDCs and is defined as substances contaminating the environment that may mimic or inhibit the effect of endogenous estrogen and therefore may influence developmental and reproductive health in humans and animals. The aim of this study was to develop, validate and implement a battery of in vitro and in vivo screening assays for e-EDCs. The study was concluded by implementing this battery of assays to assess the Eerste River, South Africa at three sampling sites, namely Jonkershoek, Stellenbosch sewage treatment works (STW) effluent and Spier for e-EDCs. The control site, Jonkershoek contained very low levels of estrone. Water from this site showed no estrogenic activity when the E-screen and the ER_ induction in MCF-7 cells. Some of the water samples collected at this site tested positive for estrogenicity when analysed with the juvenile tilapia VTG assay, whereas the rest were negative. The estrone levels in the sewage effluent extracts as well as Spier were significantly higher. The assay using ER_ protein induction by the MCF-7 cell line, the MCF-7 proliferation assay and the tilapia in vivo screen for estrogenicity showed that these samples are estrogenic. Results obtained for estrogenicity at the three different sampling sites for each of the assays in the battery were comparable. In this study we developed, validated and also implemented a battery of assays encompassing both in vitro and in vivo assays, based on different biological mechanisms, to detect estrogenic EDCs. To our knowledge, this is the first study that has used a battery of bioassays to specifically assess a South Africa river for estrogenicity...'
Al-Jandal, Noura. "The effects of estrogenic endocrine disruptors on the osmoregulatory functions in euryhaline fish." Thesis, University of Exeter, 2011. http://hdl.handle.net/10036/3131.
Повний текст джерелаTeske, Sondra Sue Gery. "Aspects of Measuring Mass Balances of Endocrine Disrupting Compounds through Wastewater Treatment." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/194944.
Повний текст джерелаBlavier, Julie. "Degradation of estrogenic endocrine disruptors by laccases: from estrogenicity monitoring methods to reactor design." Doctoral thesis, Universite Libre de Bruxelles, 2015. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/222520.
Повний текст джерелаDoctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished
Le, Fol Vincent. "Approche in vivo/in vitro du métabolisme de perturbateurs endocriniens chez le poisson zèbre (Danio rerio)." Phd thesis, Toulouse, INPT, 2015. http://oatao.univ-toulouse.fr/15125/1/lefol_1.pdf.
Повний текст джерелаCox, Brian Joseph. "Development of an assay for estrogenic endocrine disrupters involving the rat liver estrogen receptor alpha." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ31820.pdf.
Повний текст джерелаWu, Fei. "Comparative activation of estrogen receptor alpha (er alpha) by endocrine disruptors." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2433.
Повний текст джерелаZhao, Zunyang. "Removal of Estrogens at Full and Pilot Scale Livestock Manure Treatment Systems." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/26067.
Повний текст джерелаPh. D.
Kwekel, Joshua Caleb. "Cross-species comparison of estrogenic endocrine disruptor-induced, uterotrophic gene expression in the rodent." Diss., Connect to online resource - MSU authorized users, 2008.
Знайти повний текст джерелаShimada, Kiyoshi, Yonju Ha, Akira Tsukada, Noboru Saito, Shinobu Maekawa, Makoto Nishizuka, and Masayoshi Imagawa. "In vivo and in vitro screening of endocrine disrupting chemicals with estrogenic activity in Japanese quail." Science Reviews 2000 Ltd, 2005. http://hdl.handle.net/2237/9265.
Повний текст джерелаChen, Gunilla. "Changes in adipose tissue mRNA expression due to perinatal exposure to bisphenol A in rats." Thesis, Uppsala universitet, Institutionen för kvinnors och barns hälsa, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-235115.
Повний текст джерелаCoufal, Kendra. "A profile of oestrogrens and a survey of endocrine disrupters in marine turtles of Australia and Malaysia /." St. Lucia, Qld, 1998. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16547.pdf.
Повний текст джерелаOlowu, Rasaq Adewale. "Impedimetric and electrode kinetic dynamics of DNA aptamer nanobiosensors for estrogeneous endocrine disruptors." University of the Western Cape, 2011. http://hdl.handle.net/11394/8455.
Повний текст джерелаIn this work, DNA aptamer biosensor systems were developed for the detection of l7p-estradiol - an estrogeneous endocrine disrupting chemical (EDC). Endocrine disrupting chemicals are group of compounds that impact negatively on the endocrine system of humans and wildlife. High concentrations of l7p-estradiol in water or food chain disrupts the physiology of the endocrine system of various animal species, leading to feminisation in fish and stimulates the proliferation of cancer cells in humans. Aptasensor systems for the determination of l7pestradiol were prepared with three immobilization platforms: (i) poly(3,4- ethylenedioxythiophene) {PEDOT} doped with gold nanoparticles (AuNPs) to form PEDOTIAuNPs polymeric nanocomposite, (ii) generation 1 poly(propylene thiophenoimine)-copoly( 3 ,4-ethy lenedioxythiophene) dendritic star copolymer (G 1PPT -co-PEDOT), and (iii) generation 2 poly (propylene thiophenoimine)-co-poly(3,4-ethylenedioxythiophene) dendritic star copolymer (G2PPT-co-PEDOT). The morphological properties of the sensor platforms were interrogated by scanning emission microscopy (SEM) and atomic force microscopy (AFM), while their spectroscopic characteristics were studied by Fourier transform infra red spectroscopy (FTIR) and fluorescence spectroscopy. The electrochemical behaviour of the platforms and the aptasensors were studied by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and square wave voltammetry (SWV). The DNA aptamer developed for detecting 17~-estradiol and which was used in the fabrication of all aptamer biosensors in this study is a 76-mer biotinylated aptamer (5'-BiotinGCTTCCAGCTTATTGAATTACACGCAGAGG TAGCGGCTCTGCGCATTCAATGCTGCGCGCTGAAGCGCGGAAGC-3'). AulPEDOTIAuNPslAptamer (platform 1) was obtained by covalently attaching streptavidin to the polymeric nanocomposite platform using carbodiimide chemistry and the aptamer immobilized via streptavidin-biotin interaction. The electrochemical signal generated from the aptamer-target molecule interaction was monitored electrochemically using cyclic voltammetry and square wave voltammetry in the presence of [Fe(CN)6J 3-/4- as a redox probe. The signal current observed was inversely proportional to the concentration of 17Bestradiol. The aptasensor demonstrated specificity toward 17~-estradiol. The detectable concentration range of the 17B estradiol was 0.01 nM-O .09 nM with a detection limit of 3.2 pM. The 76-mer biotinylated aptamer for 17~-estradiol was incorporated into a generation 1 poly(propylenethiophenoimine )-co-poly(3 ,4-ethylenedioxythiophene) dendritic star copolymer modified Au electrode via biotin-avidin interaction (platform 2). The Bode plot shows that the charge transfer dynamics of the nanoelectrode can be frequency modulated while the AulG 1PPTco- PEDOT nanoelectrode exhibited greater semi-conductor behavior (higher phase angle value) than AulG 1PPT due to the incorporation of charged functionalized dendrimer at low frequencies (100 mHz). The biosensor response to 17~-estradiol was based on the decrease in the SWV current as the EDC binds to the ssDNA aptamer on the biosensor. The dynamic linear range of the sensor was 0.01-0.07 nM with a detection limit of7.27 pM. Synthesis of electro synthetic generation G2PPT-co-PEDOT (platform 3) was performed by copolymerization of PEDOT with G2PPT dendrimer modified electrode immersed in a solution of 0.1 M LiCI04 containing 0.1 M EDOT monomer and 0.1 M sodium dodecyl sulphate (SDS) for ten (10) cycles. The electrochemical behaviour of the dendritic star copolymer was investigated with CV and EIS in LiCI04 and phosphate buffer solutions. The results show that the electrochemical deposition of G2PPT-co-PEDOT on gold electrode decreased the electrochemical charge transfer resistance when compared to AuiPEDOTILiCI04 and AuiLiCI04 interfaces. Bode impedimetric analysis indicates that G2PPT-co-PEDOT is a semiconductor. The fabrication of two novel aptasensors (based on platforms 2 and 3) simultaneously on a screen printed micro array electrode of 96-well multichannel electrochemical robotic sensor testing system for the detection of endocrine disrupting l7~-estradiol, was also carried out. The aptasensors responses to l7~-estradiol, based on the decrease in the SWV current, were evaluated.
Holbrook, Richard David Jr. "Fate and Transport of Endocrine Disrupting Compounds during Wastewater Treatment: The Role of Colloidal and Particulate Material." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/28853.
Повний текст джерелаPh. D.
Bousoumah, Radia. "Le challenge de l’analyse multi-résidus de perturbateurs endocriniens à activité estrogénique dans les fluides et tissus biologiques humains : Choix de stratégies de préparation des échantillons et de mesure par spectrométrie de masse." Electronic Thesis or Diss., Paris, AgroParisTech, 2015. http://www.theses.fr/2015AGPT0028.
Повний текст джерелаFor over twenty years, the issue of endocrine disruptors (EDs) mobilizes the scientific community and public authorities because of the negative effects, actual or suspected, of these compounds on human health. In particular, the generation of internal exposure data (impregnation) in some subpopulations, which are recognized or assumed as being sensitive (pregnant women, fetuses, infants), is both a priority and a demanding field associated with a certain rarity. Considering their structural diversity and with regards to their physicochemical properties, the simultaneous analysis of a large panel of EDs remains a real analytical challenge. In this context, the objective of this work was to develop a multi-residue method for the simultaneous isolation and measurement of estrogenic endocrine disruptors (13 EDs in total). Firstly, an analysis method using liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) after chemical derivatisation by dansyl chloride was developed. Secondly, a molecularly imprinted polymer (MIP with phenolic imprint) was implemented for the simultaneous extraction of the targeted EDs from aqueous medium and biological matrices of increasing complexity (urine, serum, breast milk). The strategy developed on MIP was applied, after validation, to a set of samples (maternal serum, cord serum and urine of newborns). Finally, a column support grafted with estrogen receptor α (ERα column) was applied for the simultaneous isolation of the targeted compounds from an aqueous medium
Yiu, Kwok Wing. "Measuring the binding between estrogen receptor alpha and potential endocrine disruptors by fluorescence polarization and total internal reflection fluorescence." HKBU Institutional Repository, 2013. http://repository.hkbu.edu.hk/etd_ra/1503.
Повний текст джерелаMehrotra, Mamta. "Characterisation of electrochemical detection of oestrogen by using yeast oestrogen binding protein." Thesis, University of Canterbury. School of Biological Sciences, 2015. http://hdl.handle.net/10092/10223.
Повний текст джерелаSiegel, Jan. "Matematické modelování systému reverzní osmózy pro detekci estrogenů ve vodě." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-316845.
Повний текст джерелаTan, Benjamin L. L. "Chemical and Biological Analyses of Selected Endocrine Disruptors in Wastewater Treatment Plants in South East Queensland, Australia." Thesis, Griffith University, 2007. http://hdl.handle.net/10072/365603.
Повний текст джерелаThesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Faculty of Environment and Planning
Full Text
Hoffmann, Frauke. "Mating behavior as non-invasive biomarker in Xenopus laevis for the assessment of endocrine disrupting compounds." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2012. http://dx.doi.org/10.18452/16519.
Повний текст джерелаEndocrine disrupting compounds (EDCs), such as herbicides, pesticides or pharmaceuticals enter the environment via sewage effluents and especially accumulate in surface waters. Research efforts so far mainly focused on EDCs with (anti)androgenic and (anti)estrogenic modes of action (MOAs), which can interfere with reproductive biology of vertebrates. To date, biomarkers for the assessment of such compounds are invasive techniques, which are not sensitive enough to detect EDCs after short-term exposures and which cannot distinguish between the four MOAs. Hence, in this study a non-invasive method for the assessment of EDCs was developed using male African clawed frogs (Xenopus laevis) as model species. Frogs were exposed to individual (anti)androgenic and (anti)estrogenic EDCs in the surrounding water and their calling behavior was analyzed. This non-invasive method turned out to be a fast and highly sensitive biomarker for the detection of (anti)androgenic and (anti)estrogenic EDCs. Moreover, this method was able to differentiate between the four different MOAs solely by determining affected parameters of the calling behavior. It was also shown that by using this method, it might be possible to reuse already tested experimental animals, because the measured affected parameters were reversed after a period of six weeks under control conditions. Taken together the here established non-invasive behavioral method can be used as biomarker for the detection of (anti)androgenic and (anti)estrogenic EDCs. Furthermore, the high sensitivity of this testing method, as well as the possibility of analyzing vast datasets rapidly in a completely automated fashion indicate the huge potential for this rapid behavior test to become a sensitive, standardized, non-invasive biomarker.
Guimarães, Tatiane Sant\'Ana. "Detecção e quantificação dos hormônios sexuais 17 \'beta\'-estradiol (E2), estriol (E3), estrona (E1) e 17 \'alfa\'-etinilestradiol (EE2) em água de abastecimento: estudo de caso da cidade de São Carlos, com vistas ao saneamento ambiental." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-26022009-100015/.
Повний текст джерелаOne of the major problems of environmental engineering is the water contamination. The sanitary persons have been concerned with the gonadal hormones, notably the estrogen, biologically active compounds extremely, which have been referred to as etiologic agents of feminization and several types of cancers. The natural estrogen 17 \'beta\'-estradiol (E2), estriol (E3), estrone (E1) and synthetic 17 \'alpha\'-ethinylestradiol (EE2), developed for medical use of hormone replacement therapy in women and contraceptive methods, are those that attract larger concerns by the continuous introduction into the environment; hormones that have the best conformation recognized by receptors that result answers maximum, so they are considered responsible for most of the effects disruptors triggered by the wastewater disposal. The change in patterns on the sexual activity of young people and the concern with family planning, led to the large consumption of contraceptives that, in the urine, are led by the distribution net to water. The indiscriminate use of these hormones in cattle, pigs, poultry and aquaculture are responsible for part of this contaminant in the source. The hormones excreted in the urine and feces and agents from the food processing industries in the sanitary concern that the launch of effluents in nature or treated, are the main routes of contamination of the aquatic environment, either by lack of infrastructure, sanitation, or by inefficiency technological and/or operating in the removal of these compounds in the treatment plants, water or effluent. Despite having relatively short stocking-lige when compared to other organics such as pesticides, natural estrogens are continuously released into the environment, which gives them character cumulative. The proposal of this research was to verify the presence of estrogen in the gross water that arrives at the water treatment plant, after the treatment, in water treated by reverse osmosis and by Milli Q technology. To verify and quantify presence of these hormones estrogen in water supply of San Carlos-SP, examinations were conducted through immunoassay chemiluminescent and radioimunoassays. The results showed that the ETA has no efficient solution for removal of interest analytes of this research, because in the treated water were found values similar to crude water.
Gerolin, Eleonilce Rosa Rossi. "Ocorrencia e remoção de disruptores endocrinos em aguas utilizadas para abastecimento publico de Campinas e Sumare - SP." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/257939.
Повний текст джерелаTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo
Made available in DSpace on 2018-08-12T13:40:20Z (GMT). No. of bitstreams: 1 Gerolin_EleonilceRosaRossi_D.pdf: 4382249 bytes, checksum: 11ae4682864ae425b2aad5ee5844f76c (MD5) Previous issue date: 2008
Resumo: A ocorrência de compostos considerados disruptores endócrinos (DE) em efluente de Estação de Tratamento de Esgoto (ETE) e em águas superficiais em concentrações de risco para animais silvestres constitui campo de pesquisa de elevado interesse devido à probabilidade de que esses micropoluentes não sejam removidos nos processos físico-químicos empregados em Estação de Tratamento de Água (ETA) convencional. O presente trabalho avaliou a ocorrência de estrógenos naturais estrona (E1), 17ß Estradiol (E2), Estriol (E3), o estrógeno sintético 17a Etinilestradiol (EE2) e Nonilfenol (NP) em água de abastecimento público das cidades de Campinas e Sumaré-SP. Para tal, coletou-se água bruta (do rio Atibaia, na entrada da estação) e água tratada nas ETAs 3 e 4 de Campinas e ETA 2 de Sumaré, num período de três semanas. Os procedimentos analíticos empregados foram extração em fase sólida e análise por cromatografia líquida de alta eficiência e espectrometria de massa (CLAE-EM/EM). A média dos resultados obtidos para água tratada de Campinas e Sumaré foram, respectivamente, de 0,10 e 0,08 ng/L de E1, 0,92 e 1,30 ng/L de E2, 0,70 e 0,62 ng/L de E3, 275 e 472 ng/L de EE2 e 6,14 e 4 ng/L de NP. O tratamento utilizado em Campinas remove, em média, acima de 80% dos DE em estudo, com exceção de EE2, cuja remoção foi de 38%. Em Sumaré, a remoção foi da ordem de 80% de E1 e E2, 64% de E3 ; 55% NP e 41% de EE2. Considera-se que a oxidação por cloro tenha sido preponderante na remoção dos DE alertando-se, porém, para a probabilidade da formação de subprodutos potencialmente estrogênicos. Mesmo ante tal eficiência de remoção, a presença de DE, detectados em água tratada, ainda que em pequenas concentrações, pode atribuir atividade estrogênica, haja vista que estrógenos naturais e sintéticos no ambiente podem exercer efeitos mesmo em concentrações muito baixas (1ng/L).
Abstract: The occurrence of potential endocrine disruptor compounds (EDC) in wastewater treatment plant (WWTP) effluent and surface waters at high concentrations harmful for aquatic life has been an interesting research field due to the probability of these micro pollutants to break through water treatment plant (WTP). The present paper evaluated the occurrence of natural estrogens such as estrone (E1), 17ß-estradiol (E2), estriol (E3), as well as the synthetic estrogen 17a ethinylestradiol (EE2) and nonylphenol (NP) at water supply systems of Campinas and Sumaré. Raw water from Atibaia River and treated water samples were collected from Campinas WTP-3-and-4 and Sumaré WTP-2 over a three-week period. The analytic technique used was solid phase extraction and liquid chromatography/ tandem mass spectrometry (LC-MS/MS). The average results obtained for drinking water in Campinas and Sumaré were, respectively, 0.03 and 0.06ng/L for E1, 0.93 and 1.32ng/L for E2, 0.70 and 0.72ng/L for E3, 91.2 and 154ng/L for EE2 and 6.14 and 4ng/L for NP. Campinas WTP obtained an average removal of = 80% of focused EDC, except for EE2, whose efficiency was 38%; Sumaré WTP removal efficiency was 80% for E1 and E2, 60% for E3 and NP and 41% for EE2. Chlorine oxidation was probably the major treatment step for EDC removal, though potentially estrogenic by-products could have been formed as well. The presence of EDC in drinking water, despite the low concentrations, could provide estrogenic activity, since it is well known that natural and synthetic estrogen in the environment can produce effects at very low concentration (1ng/L).
Doutorado
Saneamento e Ambiente
Doutor em Engenharia Civil
Slater, Heather. "Development of a chemical analysis protocol and application with whole estrogenic and androgenic assays to assess endocrine disruptor activity during wastewater and sludge treatment processes." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/48628.
Повний текст джерелаApplied Science, Faculty of
Civil Engineering, Department of
Graduate
Verbinnen, Raphael Teixeira. "Avaliação da atividade estrogênica das águas do rio Itapecuru no município de Bacabeira-MA." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/75/75135/tde-26012015-112322/.
Повний текст джерелаThe Itapecuru river (Maranhão, Brazil) was investigated regarding its estrogenic activity by means of aquatic ecotoxicology and liquid chromatography. At Bacabeira, water samples were collected at the river Itapecuru uptake point of the public water supply system that serves about half the population of Sao Luis, Brazil. Using them, we performed 21 days chronic ecotoxicological tests using Danio rerio and Oreochromis niloticus. In these test organisms, VTG was quantified by means of enzyme-linked immunosorbent assay ELISA, whose results indicated the induction of VTG in males of both species. Therefore, the Itapecuru river water had substances in concentration sufficient to cause endocrine disruption in the reproductive system of Danio rerio and Oreochromis niloticus. To investigate the occurrence of 17β-estradiol (E2) and 17α-ethinylestradiol (EE2) in that same river, we developed an analytical method using solid phase extraction followed by high performance liquid chromatography coupled to a fluorescence detector. The method was validated and shown to be selective, precise (E2 = 3.08% and EE2 = 2.26%), exact (E2 = 78.05% and EE2 = 92.26%) and with suitable recovery (E2 = 99.24% and EE2 = 99.71%). LOD of 6.96 and 20.78 ng.L-1 and LOQ of 10.36 and 29.33 ng.L-1 were found, respectively to E2 and EE2. The robustness was assessed by Youden test and highlighted the robust and the critical points of the chromatographic method. In two of the water samples analyzed from Itapecuru River, EE2 was found, one of it with 13.48 ng.L-1 and the another below the LOQ. E2 was not detected in any of the samples.
Dell\'Acqua, Marcelo Marques. "Efeito do hormônio 17α-etinilestradiol sobre a biologia de Chironomus sancticaroli (Chironomidae, Diptera)." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-09062017-152252/.
Повний текст джерелаWater is one of the compounds of great distribution and importance in the Earth\'s. Its importance to life lies in the fact that no metabolic process occurs without its direct or indirect action. Among the various contaminating compounds in aquatic environments, hormones, natural and synthetic estrogens, should be viewed with great importance because of their persistence in the environment. 17α-ethinylestradiol (EE2) is a synthetic hormone used in the formulation of oral, transdermal, and injectable contraceptives. The present study aims to analyze the effect of the synthetic hormone 17α-ethinylestradiol on the biology of the aquatic invertebrate Chironomus sancticaroli analyzing three generations of life cycle. In the experiments, common fine sand was used (washed with deionized water, oven dried at 60ºC and muffled for 4 hours at 560ºC) and deionized water (conductivity between 25-55 μS.cm-1, hardness between 12 and 16 mg.L-1 for CaCO3, and pH between 6.5 to 7.5). Four replicates were performed using 2-liter pots for each concentration of the hormone and for the control. For the tests, 15 larvae, containing 60 g of sand and 240 ml of solution containing 17α- ethinylestradiol (1:4, sediment solution) in the concentrations of 50; 100; 200; 400; 800 and 1600 μg.L-1, and photoperiod of 12h light/12h dark and with a temperature of 22 to 26ºC. The acute tests were performed using III larvae instar without aeration and the chronic tests were performed using I instar larvae with aeration. The organisms were fed with 5 ml of a solution containing 1 liter of deionized water and 5.0 g of crushed fish feed (TetraMin®). The test performed was static, were the solution was not changed from the beginning to the end of the test of each F1, F2 and F3 generation. In acute tests (96h) the results showed that the compound under study shows no toxicity. In chronic tests only the third generation showed a low survival (43.3 to 56.6%) indicating toxicity to the test organism, which was confirmed by the one-way ANOVA test with p ≤ 0.05. The adult emergency of the organism in the third generation was of 22 days, with a delay of five days in comparison to the other treatments, indicating that the compound tested influences development. In the analysis of potential fecundity, the statistical tests indicated that there was a significant difference between the treatments and the control only in the third generation, which can be inferred that the tested compound interferes in the potential fecundity of Chironomus sancticaroli. No oral deformities were found in the larvae in the three generations analyzed. In order to do so, further studies are required, aiming at a larger number of organisms (n ≥ 100) in a larger number of generations, so that the results are more conclusive with respect to the interference of the tested compound on the biology of Chironomus sancticaroli.
Ajj, Hussein. "Influence des micropolluants en mélange sur la croissance de tumeurs testiculaires d'origine germinale." Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0215/document.
Повний текст джерелаIn vitro and in vivo epidemiological studies showed that the exposure of men to endocrine disruptors triggers the initiation and the progression of the testis cancer (Beiki et al., 2010). The fetal exposure to these products is able to alter the differentiation of germ cells in the timing of their development during the fetal life. The aim of our study was to determine the role of an endocrine disruptor mix on the proliferation of seminoma cells TCam-2. We also identified the pathways involved. In this study, we focused on the estrogen-like effects of an alkylphenol mixture called M4 (4-tert-octylphenol and 4-nonylphenol): in vitro we measured the proliferation of TCam-2 seminoma cells after M4 exposure and in vivo, we measured the tumor growth of NT2/D1 cells xenografted into Nude mice. The results highlighted the implication of ERα36 receptor, a truncated isoform of ERα, in the response to the alkylphenol mixture M4. This mixture stimulates the cell proliferation of testicular cancer cells and the expression of the ERα36 receptor. These effects are mediated by CREB phosphorylation via the PI3K-ERα36-dependant pathway, and end by downregulation of Dnmt3 genes, thus limiting the level of DNA methylation. Therefore ERα36 appears to be a promising therapeutic target for testis cancer treatment
Essandoh, Helen M. K. "Efficiency of soil aquifer treatment in the removal of wastewater contaminants and endocrine disruptors. A study on the removal of triclocarban and estrogens and the effect of chemical oxygen demand and hydraulic loading rates on the reduction of organics and nutrients in the unsaturated and saturated zones of the aquifer." Thesis, University of Bradford, 2011. http://hdl.handle.net/10454/5710.
Повний текст джерелаNetherlands Organisation for International Cooperation in Higher Education (Nuffic)
The Appendix files for this thesis are unavailable online via Bradford Scholars.
Julien, Benoit. "Caractérisation des effets métaboliques d’un mélange de polluants à faibles doses dans un modèle de souris déficientes en oestrogènes." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1092.
Повний текст джерелаMenopause is a risk factor associated with the development of metabolic diseases. Because of estrogen deficiency, postmenopausal women may be at particular risk when exposed to chemical agents that can disrupt the endocrine system. To get more insight, we have developed a model of ovariectomized mice supplemented or not with estradiol (E2), and chronically exposed to a mixture of pollutants (TCDD, PCB153, DEHP and BPA) added to an obesogenic diet. Each pollutant was used at a dose close to the Tolerable Daily Intake dose, and the exposure had covered different stages of development, including or not the maternal period (gestation + lactation). Our results indicate that in diet-induced obesity, ovariectomy triggered weight gain, increase glucose intolerance and insulin resistance. This phenotype was associated with decreased estrogenic signaling in liver and deregulation of adipogenesis and inflammation in adipose tissues. Interestingly, the mixture of pollutants reduced the deleterious impact of ovariectomy on the metabolic phenotype, possibly through an alleviation of estrogenic signaling in both liver and adipose tissues. These data were not reproduced in mice not exposed to pollutants during the maternal life. In conclusion, the mixture of pollutants displayed some estrogeno-mimetic activity. This could have implications in understanding the role of environmental pollutants in the development of metabolic diseases in women in menopausal transition
Essandoh, Helen Michelle Korkor. "Efficiency of soil aquifer treatment in the removal of wastewater contaminants and endocrine disruptors : a study on the removal of triclocarban and estrogens and the effect of chemical oxygen demand and hydraulic loading rates on the reduction of organics and nutrients in the unsaturated and saturated zones of the aquifer." Thesis, University of Bradford, 2011. http://hdl.handle.net/10454/5710.
Повний текст джерелаSilva, Mariana Aguilera Alencar da. "Avaliação da neurotoxicidade do Bisfenol A em cultura primária de hipocampo." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/9/9141/tde-04102016-152552/.
Повний текст джерелаBisphenol A (BPA) is used in the manufacture of polycarbonate plastics and epoxy resins. The prenatal exposure to this agent may cause several effects, such as anticipation of puberty, prostate hyperplasia, reduced number of sperm, reduced testosterone levels, alteration in the development and tissue organization of the mammary gland, decreased cellular response induced by hormones, breast cancer, diabetes, cardiovascular disease, changes in the functions of liver enzymes, and effects on cognitive development. Few studies have evaluated the effects of BPA in neuronal cells, however there are evidences that this agent may induce apoptosis. This work aims to study the neurotoxicity of BPA, by analyzing the signaling pathways of apoptosis in hippocampus primary culture. Cells were exposed to BPA at 50, 100, 150, 200, and 250 µM (0.1% DMSO v/v) for 6, 12, 24, and 48 hours for the assay of mitochondrial activity (MTT) and the release of the enzyme lactate dehydrogenase (LDH). From the results of MTT and LDH, new exposure times (3, 6 and 9 hours) and only 200 and 250 µM were used. In this new experimental design we performed the quantification of the BPA concentration in the primary culture by HPLC-PDA, intracellular Ca2+ quantification by Fluo-4 AM assay and the characterization of the mechanisms involved in cell death by flow cytometry and Western Blotting assays. Furthermore, evaluation of the estrogen receptor ER-α and ER-β was done by Western Blotting. Our results demonstrate that about 20% of the BPA concentration of 250 µM after 6 hours of exposure and 18% for the concentration of 200 µM with 9 hours of exposure were absorbed by the cell culture. Cells exposed to 200 and 250 µM of BPA for 12, 24 and 48 hours, showed a significant decrease in mitochondrial function, by the MTT assay, compared to control. However, there was no release of LDH into the culture medium for any of the BPA concentrations in any of incubation times studied, which suggests no rupture of the plasma membrane by BPA. Apoptotic activity was observed after 6 hours of exposure to 250µM BPA by flow cytometry. It was not observed cell necrosis and changes in intracellular calcium concentration in any of the studied conditions. Regarding the cell death markers, exposure to 250 µM BPA in all periods of exposure resulted in an increased Bax/Bcl-2 ratio; moreover, an increase in caspase 8, 9 and 3 was detected after exposure to 250 µM BPA for 6 hours. Taken together, these findings indicate that BPA activates both the intrinsic and the extrinsic pathway during the apoptotic process. We also verified by Western Blotting the presence of the estrogen receptors ER-α and ER-β at the primary culture of hippocampus, and that they can be modulated by BPA. The exposure to 200 and 250 µM BPA for 6 hours caused an increase of ER-α and ER-β, however, 9 hours of exposure to 200 µM and 250 µM BPA increased the expression of ER-α and ER-β, respectively. In conclusion, BPA can lead hippocampal neuronal cells to death by both, intrinsic and extrinsic, apoptotic pathways and this process is more evident at 250 µM BPA after 6 hours of exposure. Furthermore, we suggest that the increase of both estrogen receptors might represent an attempt to interrupt or reverse the cell death process.
Mercado-Feliciano, Minerva. "Estrogenic Activity of the Polybrominated Diphenyl Ether Flame Retardant Mixture DE-71." Thesis, 2008. http://hdl.handle.net/1805/1603.
Повний текст джерелаPolybrominated diphenyl ethers (PBDEs) are widely used flame retardants suspected to act as endocrine disruptors. We tested the commercial PBDE mixture DE-71 and its in vivo metabolites for estrogenic activity. MCF-7 breast cancer cells culture, ERE-luciferase gene expression, 3H-β-estradiol displacement from recombinant ERα, and ovariectomized (OVX) mice served as bioassays. Although DE-71 did not bind ERα, it was able to increase MCF-7 cell proliferation and this was prevented by the antiestrogen fulvestrant. DE-71 co-treatment reduced the effect of estradiol in MCF-7 cells. In the OVX mouse (BALB/c) 3-day assay, DE-71 administered alone had no effect on uterine or vaginal tissues but when administered subcutaneously potentiated estradiol’s effect on uterine weight in a dose-dependent manner. DE-71 administered SQ to BALB/c mice for 34 days slightly increased uterine epithelial height (UEH), vaginal epithelial thickness (VET) and mammary ductal lumen area, and attenuated the estradiol-induced increase in UEH; these effects were not seen in C57BL/6 mice. DE-71 increased liver weight in BALB/c, C57BL/6 and estrogen receptor-alpha knockout (ERαKO) mice. Liver cytochrome P450 1A (CYP1A) and CYP2B activities increased 2.5-fold and 7-fold respectively when DE-71 was administered PO, but only CYP2B increased (5-fold) after SQ treatment. Six OH-PBDE metabolites were found in mice after 34-day DE-71 treatment and all were able to bind recombinant ERα. Para-hydroxylated metabolites displayed a 10- to 30-fold higher affinity for ERα compared to ortho-hydroxylated PBDEs. Para-OH-PBDEs induced ERE-luciferase and produced an additive effect when coadministered with β-estradiol. DE-71 was also additive with β-estradiol. At high concentrations (≥ 5x10-5 M), ortho-OH-PBDEs were antiestrogenic in the ERE-luciferase assay. In conclusion, DE-71 behaves as a weak estrogen in both MCF-7 breast cancer cells and ovariectomized adult mice. Mice strain, treatment route and duration determined if DE-71 was estrogenic. BALB/c mice are more susceptible to DE-71 effects in estrogen target tissues than C57BL/6 mice. DE-71 increased liver weight, 5%-51% depending on mouse strain and treatment regime, independently of ERα. The observations that the DE-71 mixture does not displace 3H-β-estradiol from ERα while the hydroxylated metabolites do, suggest that the cellular and tissue effects were due to a metabolic activation of individual congeners.
"Effect of dietary and environmental endocrine disruptors on estrogen metabolic enzyme expression." Thesis, 2009. http://library.cuhk.edu.hk/record=b6074976.
Повний текст джерелаBreast cancer is one of the most prevalent female cancers in Hong Kong and western countries. Prolonged exposure to estrogen has been associated with increased risk of breast cancer. Many enzymes are responsible for estrogen metabolism, for instance, aromatase (CYP19) is responsible for biosynthesis; CYP1 family enzymes hydroxylate estrogen; COMT (catechol-O-methyltransferase) inactivates the hydroxyestrogen; and UDP-glucuronosyltransferase 1A1 (UGT1A1) eliminates the estrogen metabolites. In this project, we employed cell and animal models to address estrogen metabolism-related questions under the influence of endocrine disruptors.
TCDD is a prototype compound of a whole class of halogenated aromatic hydrocarbons termed dioxin-like contaminants, which are also known to be endocrine disruptors. Because of their persistence in the environment dioxins are one of the most concerned classes of carcinogens. Humans can be exposed to this pollutant through contaminated food, air, drinking water, etc. We found that pre-ovariectomy administration of TCDD could significantly reduce aromatase expression in the brain but increase the expression in the adipose tissue. Our results suggested that the timing of exposure to the toxicant could determine the estrogenicity of TCDD.
The present project indicated that endocrine disruptors can alter the metabolism of estrogen; however, the significance of this alteration may be specific to tissues' phenotype and the timing of exposure.
Ye Lan.
Source: Dissertation Abstracts International, Volume: 73-01, Section: B, page: .
Thesis (Ph.D.)--Chinese University of Hong Kong, 2009.
Includes bibliographical references (leaves 169-192).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstract also in Chinese.
Medková, Jaroslava. "Optimalizace stanovení endokrinních disruptorů v čistírenských kalech a aplikace metody v reálných vzorcích." Master's thesis, 2012. http://www.nusl.cz/ntk/nusl-307047.
Повний текст джерела"Effect of endocrine disruptors on the synthesis of estrogen and corticotrophin-releasing hormone in vitro and in vivo." Thesis, 2011. http://library.cuhk.edu.hk/record=b6075154.
Повний текст джерелаThesis (Ph.D.)--Chinese University of Hong Kong, 2011.
Includes bibliographical references (leaves 141-154).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstract also in Chinese.
Cotter, Kellie Anne. "Alternative splicing of estrogen receptor alpha: potential mechanism for endocrine disruption and adaptation in teleost fishes." Thesis, 2014. https://hdl.handle.net/2144/15399.
Повний текст джерелаDytczak, Magdalena Anna. "Using ozonation and alternating redox potential to increase nitrogen and estrogen removal while decreasing waste activated sludge production." 2008. http://hdl.handle.net/1993/3062.
Повний текст джерелаOctober 2008
Hill, Corinne E. "Effects of Developmental Exposures of Two Emerging Environmental Toxicants on Estrogen-Sensitive Endpoints." 2015. https://scholarworks.umass.edu/masters_theses_2/200.
Повний текст джерелаKlammer, Holger. "Pharmakologische Untersuchungen zu endokrinen Effekten des UV-Filters Ethylhexyl-methoxycinnamat." Doctoral thesis, 2006. http://hdl.handle.net/11858/00-1735-0000-0006-ABC4-2.
Повний текст джерелаAdamusová, Hana. "Využití vysokoúčinných separačních metod pro analýzy biologicky aktivních látek." Doctoral thesis, 2017. http://www.nusl.cz/ntk/nusl-369437.
Повний текст джерела