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Tesis sobre el tema "Endokriner Disruptor"

Autor: Grafiati
Publicado: 4 de junio de 2021
Última modificación: 13 de febrero de 2022

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1

Hofmann, Peter Josef. "Aufbau eines Reportergenassays zur Untersuchung der Wechselwirkung endokriner Disruptoren mit der T 3-regulierten Transaktivierung". Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2008. http://dx.doi.org/10.18452/15813.

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Das Schilddrüsenhormon Triiodthyronin (T3) ist ein essenzieller Regulator physiologischer Prozesse der Entwicklung, des Wachstums und im Intermediärstoffwechsel. Täglich werden zahlreiche natürliche und synthetische Stoffe aufgenommen, die mit dem endokrinen System interferieren und deshalb als Endokrine Disruptoren (ED) bezeichnet werden. Zur Untersuchung einer direkten Interferenz von ED mit den Schilddrüsenhormonrezeptoren (TR) und ihrer transkriptionellen Aktivität wurde im Rahmen dieser Arbeit ein neues Luziferase-basiertes T3 Reportergensystem mit TRalpha1-transfizierten humanen Leberzellen aufgebaut. Durch Validierung mit dem synthetischen TR-Agonisten GC-1 und dem Antagonisten NH-3 konnte nachgewiesen werden, dass dieser Assay ein hoch-sensitives System zur Analyse von agonistischen sowie antagonistischen Effekten von Testsubtanzen darstellt. Zur Bestimmung der endokrinen Aktivitäten einiger humanrelevanter Vertreter aus den Stoffkategorien der Nahrungsmittel, Kosmetika, Pestizide und Industriechemikalien wurden Dosis-Wirkungskurven in Aktivierungs- und T3-Kompetitionsexperimenten ermittelt. In mikromolaren Konzentrationen wirkten von insgesamt 21 Testsubstanzen einige als reine Agonisten oder Antagonisten während andere gemischt agonistische/antagonistische Effekte hatten. Aufgrund ihrer hier beobachteten Effekte und der gegebenen Humanexposition wird eine eingehendere Analyse von 4-Methylbenzyliden Campher, 4-Nonylphenol, Acetochlor, Benzophenon 2, Benzophenon 3, Bisphenol A, Genistein, Octylmethoxycinnamat, Tetrabromobisphenol A und Xanthohumol empfohlen. Außerdem erwiesen sich einige Metaboliten von Schilddrüsenhormonen als potente Agonisten im T3-Reportergenassay und bedürfen weiterer Aufmerksamkeit. Für die molekulare Charakterisierung der Einflüsse solcher Substanzen auf die T3-regulierte Transaktivierung konnte mit dem hier etablierten Bioassay ein zuverlässiges neues Testsystem für reproduzierbare Screeningserien geschaffen werden.
Triiodothyronine (T3) is a crucial regulator of many physiological processes during development, growth and metabolism. A variety of natural and synthetic substances, which are collectively termed endocrine disrupters (ED) due to their interference with the endocrine system, is taken up on a daily base. A novel luciferase-based T3-responsive reporter gene system employing a human liver cell line transfected with thyroid hormone receptor (TR) alpha1 was established in this work to elucidate the potential molecular interference of certain ED with TR and their transcriptional activity. This assay was validated to be a highly sensitive and reliable tool for analyzing agonistic and antagonistic effects of test compounds using the synthetic TR agonist GC-1 and the antagonist NH-3. Dose-response data of test compounds contained in food, cosmetics, pesticides, plasticizers and other industrial chemicals were obtained after applying the substances alone in activation assays or in combination with T3 in competition assays. In total 21 test compounds were screened of which some acted as pure agonists or antagonists while others were mixed agonists/antagonists in the micromolar concentration range and only one was without effect. Follow-up studies are recommended for some of these substances with regard to their effects as determined in this bioassay and in light of information known on human exposure, i.e., 4-methylbenzyliden camphor, 4-nonylphenol, acetochlor, benzophenone 2, benzophenone 3, bisphenol A, genistein, octylmethoxycinnamate, tetrabromobisphenol A and xanthohumol. In addition some endogenous metabolites of thyroid hormones were surprisingly potent agonists in the T3 reporter gene assay and merit further attention. The novel bioassay established here represents a reliable tool for the screening and molecular characterization of substances interfering with T3-mediated transactivation of gene expression.
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2

Bacinski, Anja [Verfasser]. "Inhibitorische Wirkung endokriner Disruptoren auf die humane Thyreoperoxidase / Anja Bacinski". Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2013. http://d-nb.info/1031098194/34.

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3

Caldarelli, Antonio. "A study on endocrine disrupters in the environment through the microarray technology". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2007. http://nbn-resolving.de/urn:nbn:de:swb:14-1175076879253-16448.

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Due to the current rise of exposure to natural and synthetic compounds in our daily life, the debate concerning the safety of many substances is becoming increasingly relevant. The estrogenic activity of various compounds, described as xenoestrogens, is the major part of this debate. Humans beings are exposed to these substances from different environmental contaminations ranging from conscious intake of estrogenic substances, as in contraception or in hormone replace therapy (HRT), to unconscious exposure, from food, the use of synthetic material in daily life and air and water pollution. At this point the need for methods to investigate the activity and the safety of these substances is becoming increasingly important. Classical methods for the analysis of the estrogenic activity of substances, like batteries of in vivo test systems on the rat uterotrophic assay are not able to describe the different pathways of action of recently discovered estrogenic substances. This evidence was already shown by the Organization for Economic Cooperation and Development (OECD), introducing new test guidelines for the investigation of effects of endocrine disruptors (according to enhanced Test Guideline 407). As reviewed by Nilsson (Nilsson et al., 2001), after the interaction of the estrogens with the Estrogen Receptor (ER) in the cells, the mechanism of activation possible is not only via direct binding of the ER to the Estrogen Responsive Elements (EREs) present in the promoter region of the target gene, very well described for many target genes, but that also other mechanisms are used: the interaction of the ER with the AP 1, Sp 1 and NFkB modes, that are discovered but not yet comprehensively described. The aim of my work is to produce a microarray DNA chip for the investigation of the estrogenic activity of different compounds present in the environment. The chip will consist of a selection of 100 genes that are estrogen responsive and it will cover the spectrum of activities of estrogenic compounds in various organs of the body. In the gene selection, genes were chosen that are estrogen responsive in the classical target tissues of estrogens, linked to reproduction, like uterus and mammary gland, and also in tissues not related to reproduction like liver, bones and capillars. In addition, other genes are included to monitor different pathways that are related to disease states; control of cell proliferation, apoptosis or cancer related genes. Currently these kinds of investigations are already in process, but by other methods which are more time consuming and with a lower throughput e.g. the gene expression profiling using the real time RT-PCR. The use of microarray’s satisfies the need for a less time consuming, high throughput method, to obtain a fast characterization of the gene expression finger print of the candidate substances and their mechanism of action in the organism. In my work I investigated the estrogenic potency of different Xenoestrogens that commonly occur in our daily life, in rat cells and tissue using well known estrogen sensitive genes like C3, Clu, IGFBP1 and CaBP9k. I focused on their effect on cell proliferation, studying PCNA expression. For the first time sensitivity of the gene CA2 was proofed in liver and uterus. A new identified mRNA sequence, r52, was characterized for its sensitivity to estrogenic exposure. This sequence was investigated at the molecular level expanding the known nucleic sequence. I produce a microarray chip with 16 genes to investigate the estrogenic potency of different compounds. As proof of principle of the microarray method completely produced in house I compared the result of gene expression obtained by the chip to that obtained by real time RT PCR finding a similarity of results. This new established method is less sensitive than the real-time RT PCR but allows a high throughput of gene expression analysis producing at the end a more complete picture of the expression signature of a compound.
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4

Caldarelli, Antonio. "A study on endocrine disrupters in the environment through the microarray technology". Doctoral thesis, Technische Universität Dresden, 2006. https://tud.qucosa.de/id/qucosa%3A24861.

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Due to the current rise of exposure to natural and synthetic compounds in our daily life, the debate concerning the safety of many substances is becoming increasingly relevant. The estrogenic activity of various compounds, described as xenoestrogens, is the major part of this debate. Humans beings are exposed to these substances from different environmental contaminations ranging from conscious intake of estrogenic substances, as in contraception or in hormone replace therapy (HRT), to unconscious exposure, from food, the use of synthetic material in daily life and air and water pollution. At this point the need for methods to investigate the activity and the safety of these substances is becoming increasingly important. Classical methods for the analysis of the estrogenic activity of substances, like batteries of in vivo test systems on the rat uterotrophic assay are not able to describe the different pathways of action of recently discovered estrogenic substances. This evidence was already shown by the Organization for Economic Cooperation and Development (OECD), introducing new test guidelines for the investigation of effects of endocrine disruptors (according to enhanced Test Guideline 407). As reviewed by Nilsson (Nilsson et al., 2001), after the interaction of the estrogens with the Estrogen Receptor (ER) in the cells, the mechanism of activation possible is not only via direct binding of the ER to the Estrogen Responsive Elements (EREs) present in the promoter region of the target gene, very well described for many target genes, but that also other mechanisms are used: the interaction of the ER with the AP 1, Sp 1 and NFkB modes, that are discovered but not yet comprehensively described. The aim of my work is to produce a microarray DNA chip for the investigation of the estrogenic activity of different compounds present in the environment. The chip will consist of a selection of 100 genes that are estrogen responsive and it will cover the spectrum of activities of estrogenic compounds in various organs of the body. In the gene selection, genes were chosen that are estrogen responsive in the classical target tissues of estrogens, linked to reproduction, like uterus and mammary gland, and also in tissues not related to reproduction like liver, bones and capillars. In addition, other genes are included to monitor different pathways that are related to disease states; control of cell proliferation, apoptosis or cancer related genes. Currently these kinds of investigations are already in process, but by other methods which are more time consuming and with a lower throughput e.g. the gene expression profiling using the real time RT-PCR. The use of microarray’s satisfies the need for a less time consuming, high throughput method, to obtain a fast characterization of the gene expression finger print of the candidate substances and their mechanism of action in the organism. In my work I investigated the estrogenic potency of different Xenoestrogens that commonly occur in our daily life, in rat cells and tissue using well known estrogen sensitive genes like C3, Clu, IGFBP1 and CaBP9k. I focused on their effect on cell proliferation, studying PCNA expression. For the first time sensitivity of the gene CA2 was proofed in liver and uterus. A new identified mRNA sequence, r52, was characterized for its sensitivity to estrogenic exposure. This sequence was investigated at the molecular level expanding the known nucleic sequence. I produce a microarray chip with 16 genes to investigate the estrogenic potency of different compounds. As proof of principle of the microarray method completely produced in house I compared the result of gene expression obtained by the chip to that obtained by real time RT PCR finding a similarity of results. This new established method is less sensitive than the real-time RT PCR but allows a high throughput of gene expression analysis producing at the end a more complete picture of the expression signature of a compound.
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5

Schneider, Christian. "Entwicklung, Optimierung und Validierung eines Immunoassays zur sensitiven Detektion des endokrinen Disruptors 17alpha-Ethinylestradiol". [S.l. : s.n.], 2006. http://nbn-resolving.de/urn:nbn:de:bsz:16-opus-60128.

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6

Levy, Gregor. "Gewässerbelastung mit endokrin wirksamen Substanzen". Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2005. http://dx.doi.org/10.18452/15224.

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In der vorliegenden Arbeit wurde untersucht, inwieweit die Reproduktionsbiologie von aquatischen Lebewesen durch die Gewässerbelastung mit endokrin wirksamen Substanzen (endocrine disruptors, ED) beeinflusst wird. Mit dem Amphib Xenopus laevis steht ein etabliertes Studienmodell zur Untersuchung der Wirkungen von ED auf die Reproduktionsbiologie zur Verfügung, das für die vorliegenden Studien modifiziert und erweitert sowie mit gewässeranalytischen Methoden verknüpft wurde. Die Gefährdung wasserlebender Tiere durch Gewässerbelastung mit ED kann erfasst werden, indem die Wirkung einer ausgewählten Einzelsubstanz auf die Reproduktionsbiologie untersucht wird. Anschließend erfolgt ein Nachweis der Substanz in Umweltproben. Durch Expositionsversuche, histologische Untersuchungen und Expressionsnachweis eines molekularen östrogenen Biomarkers konnte festgestellt werden, dass Bisphenol A (BPA) in Kaulquappen von Xenopus laevis verweiblichend wirkt und seine Effekte über eine Bindung an den Östrogenrezeptor vermittelt. Chemische Analysen während der Expositionsversuche zeigten, dass BPA von den Kaulquappen aufgenommen wird und dass eine geringe Abbaubarkeit der Substanz während eines Zeitraums von 48 Stunden besteht. Die Analyse von BPA in Wasserproben, die aus dem Fluss Alb oder aus Kläranlagenausläufen stammten, zeigte, dass BPA im Gewässer in relevanten Konzentrationen vorhanden ist und hauptsächlich durch eine Kläranlage in den Fluss eingeleitet wird. In einem Gewässer liegt allerdings ein Gemisch aus unterschiedlichen ED mit verschiedenen Wirkmechanismen vor. Die Gewässerbelastung mit endokrin wirksamen Substanzen kann weiterhin untersucht werden, indem Gewässerextrakte fraktioniert und in in vitro-Screeningmethoden getestet werden. Als Screeningmethoden dienten Rezeptorbindungsstudien an Östrogen- und Androgenrezeptoren sowie die Behandlung von Leberzellkulturen mit den Gewässerextrakten aus der Alb, um eine Regulation der Expression bestimmter Biomarkergene durch potenzielle ED nachzuweisen. Dazu wurde als neuer (anti)androgener und (anti)östrogener Biomarker das Retinol-binding Protein eingeführt. Die Untersuchung der Gewässerextrakte mit diesen Methoden zeigte, dass die Alb eine Belastung mit endokrin wirksamen Substanzen aufweist und dass hauptsächlich östrogen wirksame Substanzen vorkommen. Die Proben aus den Kläranlagenausläufen weisen die höchste endokrine Aktivität auf.
The present study examined the influence of endocrine active compounds (endocrine disruptors, ED), which are present in surface waters, on reproductive biology of aquatic organisms. The amphibian Xenopus laevis is a well-established model organism for the study of effects of ED on reproduction. It has been modified and broadened for the purpose of this study, and it was combined with chemical methods for water analyses. It is possible to assess water pollution with ED by detecting effects on repro-ductive biology of one particular substance, and then by looking for this substance in environmental water samples. We showed the feminizing potency of Bisphenol A (BPA) in conducting exposure experiments with tadpoles, in examining histological samples of gonads and in detecting the induction of the expression of a molecular estrogenic biomarker. BPA was recognized to mediate its effects via binding to the estrogen receptor. Moreover, analysis of BPA during exposure experiments revealed that BPA is taken up by tadpoles and is not readily degradable during a time period of 48 hours. Chemical analyses of environmental water samples from the river Alb or samples from sewage treatment works (STW) showed that BPA is released into the environment by STW effluents. In surface waters, there are different kinds of ED with different modes of action. Thus, it is another possibility to assess water pollution with ED by fractionating environmental water samples and by testing these fractions in rapid in vitro-screening methods. In the present work, receptor binding assays were carried out, both examining the binding to estrogen and androgen receptors. Furthermore, Xenopus laevis hepatocyte cultures were treated with fractions of environmental samples and biomarker expression was detected. A new biomarker to assess (anti)androgenic or (anti)estrogenic modes of action, respectively, was established. This new biomarker was the Retinol-binding Protein. The results obtained by these methods revealed that the river Alb is mainly polluted with estrogenic ED. Samples from STW effluents possessed the highest endocrine activity.
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7

Fojt, Jakub. "Stanovení organických sloučenin cínu v životním prostředí". Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2018. http://www.nusl.cz/ntk/nusl-376809.

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Organotin compounds are one of the most produced and most used organometallic compounds. Some of these substances are endocrine disruptors, persistent organic polutants and their high toxic effects are observed. That’s why their presence in the environment caused by human activity could endanger many organisms. The aim of this thesis is summarize their properties and their occurrence in the environment. Then the quick, easy and relatively cheap method for determination of trialkyltin compounds in heavily poluted aquatic sediments using capillary zone electrophoresis is developed.
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8

Ivana, Fratrić. "Uticaj organofosfornih pesticida na pojavu nespuštenog testisa". Phd thesis, Univerzitet u Novom Sadu, Medicinski fakultet u Novom Sadu, 2019. https://www.cris.uns.ac.rs/record.jsf?recordId=110721&source=NDLTD&language=en.

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Nespušteni testis predstavlja odsustvo testisa u skrotumu sa jedne ili obe strane. Faktori rizika za pojavu nespuštenog testisa obuhvataju genetsku predispoziciju, prevremeno rođenje, nisku porođajnu masu i prenatalnu izloženost endokrinim disruptorima ili duvanskom dimu. Endokrini disruptori se definišu kao egzogene supstance koje imaju uticaj na homeostazu organizma i proizvodnju reproduktivnih hormona. U ovoj grupi nalaze se organofosforni pesticidi koji se široko upotrebljavaju u poljoprivredi. Većina organofosfornih pesticida ima antiandrogeni uticaj i uz činjenicu da živimo u pretežno agrarnoj sredini predmet su našeg interesovanja. Cilj istraživanja je da se utvrdi razlika u izloženosti organofosfornim pesticidima korišćenjem upitnika kreiranog po modelu standardizovanog Evropskog upitnika QLK 4-1999-01422 kod osoba koje su rodile zdravu mušku decu i osoba koje su rodile decu sa nespuštenim testisom. Pored toga, cilj istraživanja je i da se odredi i uporedi vrednost metabolita organofosfornih pesticida (dimetilfosfat, dimetilditiofosfat, dietilfosfat, dietiltiofosfat i dietilditiofosfat) u urinu majki koje su rodile mušku decu sa nespuštenim testisima i majki koje su rodile zdravu mušku decu. Metodologija: Rad je radomizovano, prospektivno, kliničko istraživanje sprovedeno na Klinici za ginekologiju i akušerstvo Kliničkog centra Vojvodine i Katedri za farmakologiju i toksikologiju Medicinskog fakulteta, Univerziteta u Novom Sadu. U kliničko istraživanje uključeno je 50 porodilja koje su rodile mušku decu sa nespuštenim testisima (eksperimentalna grupa) i 53 porodilje koje su rodile zdravu mušku decu (kontrolna grupa) u periodu od oktobra 2012. godine do aprila 2018. godine. Tokom boravka u porodilištu ispitanice su popunjavale upitnik o navikama nakon čega im je uzet uzorak urina radi analiziranja nivoa metabolita OF pesticida. Uzorci urina su pripremljeni metodom koju su opisali Wu i saradnici 2010. godine, a potom analizirani na gasnom hromatografu masenom spektrofotometaru marke Agilent 7890A. Rezultati: Ispitivane grupe se ne razlikuju po starosti ispitanica (prosečna starost kontrolne grupe 29,41 ± 5,58 godina, a eksperimentalne 30,54 ± 4,87 godina). U obe grupe prosečno je ispitanicama ovo bila druga trudnoća. Ispitanice se nisu razlikovale ni po načinu porođaja. Prosečna gestacijska nedelja trudnoće na porođaju iznosila je 39,45 ± 1,38 nedelja za kontrolnu grupu i 39,20 ± 1,38 nedelja za eksperimentalnu grupu, a porođajna masa novorođenčeta 3527,30 ± 470,16 g u kontrolnoj grupi i 3404,37 ± 508,20 g u eksperimentalnoj grupi. Statistički značajna razlika postoji u odnosu na mesto stanovanja (50,9 % ispitanica kontrolne grupe i 77,6 % ispitanica eksperimentalne grupe žive u gradu), jedinicu stanovanja (67,9 % kontrolne i 45,7 % ispitanica eksperimentalne grupe žive u kući) i načinu začeća (6 % ispitanica eksperimentalne i 1,9 % ispitanica kontrolne grupe prijavilo je IVF kao način začeća). Skoro polovina ispitanica obe grupe su pušači, a njih 32,7 % kontrolne grupe i 38,8 % eksperimentalne pušile su i tokom trudnoće. Izloženost pesticidima prijavilo je 50,9 % ispitanica kontrolne i 44 % ispitanica eksperimentalne grupe, a profesionalnu izloženost prijavilo je 3 ispitanice kontrolne i 2 ispitanice eksperimentalne grupe. Ispitanice se ne razlikuju ni po poreklu voća i povrća koje konzumiraju, kao ni po vrsti voća koje su konzumirale tokom trudnoće. Prosečne izmerene vrednosti DMF u kontrolnoj grupi iznose 5,604 ± 6,103 ug/L, a u eksperimentalnoj 4,815 ± 6,729 ug/L. Izmerene vrednosti DEF u kontrolnoj grupi su 0,408 ± 0,447 ug/L, a u eksperimentalnoj 0,461 ± 0,593 ug/L. Nivo DMDTF u kontrolnoj grupi bio je 0,431 ± 0,508 ug/L, a u eksperimentalnoj 0,547 ± 0570 ug/L, a DETF 0,403 ± 0,606 ug/L u kontrolnoj i 0,529 ± 0,725 ug/L u eksperimentalnoj grupi. Ni jedan metabolit ne pokazuje statistički značajnu razliku u ispitivanim grupama. Slične vrednosti dobijene su i za vrednosti korigovane za nivo kreatinina. Univarijantna regresiona analiza pokazala je da ispitanice koje žive u gradu imaju 3,3 puta veće šanse da rode dete sa nespuštenim testisom, a one koje žive u stanu imaju 2,5 puta veće šanse za isti ishod. Statistički značajna razlika primećena je u nivou DEDTF u zavisnosti od starosti ispitanica i jedinici stanovanja. Više vrednosti DETF dobijene su kod ispitanica koje su bile na hormonskoj terapiji tokom trudnoće. Ispitanice koje su prijavile da su bile izložene pesticidima tokom trudnoće u urinu su imale statistički značajno više vrednosti DMDTF u odnosu na ispitanice koje su se izjasnile da nisu bile izložene pesticidima. Slični rezultati za vrednost DEDTF dobijeni su kod ispitanica koje su se izjasnile da poseduju kućne ljubimce. Statistički više vrednosti DEF i DETF korigovano za nivo kreatinina dobijene su kod ispitanica koje nisu konzumirale jabuke, a više vrednosti DEF i DEDTF dobijene su kod ispitanica koje su konzumirale maline i kupine tokom trudnoće. Ostale grupe nisu pokazale statistički značajnu razliku među ispitivanim grupama. Zaključci: Izloženosti trudnica OF pesticidima nije značajno veća u grupi majki koje su rodile decu sa nespuštenim testisom u odnosu na izloženost OF pesticidima kod majki zdrave muške dece. Vrednosti metabolita OF pesticida (dimetilfosfat, dimetilditiofosfat, dietilfosfat, dietiltiofosfat, dietilditiofosfat) u urinu majki koje su rodile mušku decu sa nespuštenim testisima nije viša u odnosu na vrednosti metabolita OF pesticida (dimetilfosfat, dimetilditiofosfat, dietilfosfat, dietiltiofosfat, dietilditiofosfat) izmerene u jutarnjem urinu majki koje su rodile zdravu mušku decu.
Undescended testis is the absence of testis in the scrotum on one or both sides. Risk factors for the occurrence of undescended testis include genetic predisposition, premature birth, low birth weight and prenatal exposure to endocrine disruptors or tobacco smoke. Endocrine disruptors are defined as exogenous substances that can affect homeostasis of the organism and the production of reproductive hormones. In this group are organophosphorus pesticides that are widely used in agriculture. Most of organophosphorus pesticides have anti-androgenic effect and with the fact that we live in a predominantly agricultural area, they are the focus of our interest. The aim of the research: The aim of this study is to determine the difference in exposure to organophosphorous pesticides using questionnaires created by standardized European model questionnaire QLK 4-1999-01422 in individuals who gave birth to a healthy male children and women who gave birth to children with undescended testis. In addition, the aim of this study is to determine and compare the value of metabolites of organophosphorus pesticides (dimethylphosphate, dimethyldithiophosphate, diethylphosphate, diethylthiophosphate and diethyldithiophosphate) in the urine of mothers who gave birth to male children with undescended testis and mothers who gave birth to healthy male children. Methodology: This work is randomized, prospective, clinical research conducted at the Clinic for gynaecology and obstetrics of the Clinical center of Vojvodina and the Department of Pharmacology and toxicology of the Faculty of Medicine, University of Novi Sad. This clinical research includes 50 new mothers that gave birth to male children with undescended testes (experimental group) and 53 new mothers that gave birth to healthy male children (control group) in the period from October 2012 to April 2018. During their stay at the maternity hospital the subjects were asked to fill out a questionnaire about habits and to give a urine sample for analyzing the level of metabolites of organophosphus pesticides. Urine samples were then prepared using the method described by Wu and associates 2010, and analyzed on gas chromatograph with a mass spectrophotometer Agilent 7890A brand. Results: Study groups do not differ according to the age of women (average age of control group is 29.41 ± 5.58 years, and experimental 30.54 ± 4.87 years). In both groups this was second pregnancy on average. The subjects did not distinguish either by the way of delivery. The average gestational weeks of pregnancy to childbirth was 39.45 ± 1.38 weeks for the control group and 39.20 ± 1.38 weeks for the experimental group, and birth weight of newborn was 3527.30 ± 470.16 g in control group and 3404.37 ± 508.20 g in the experimental group. There is no statistically significant difference in relation to the place of residence (50.9 % of the control group and 77.6 % of experimental live in the city), the living unit (67.9 % and 45.7 % of the control and experimental groups are living in the house) and the way of conception (6 % of experimental and 1.9 % of the control group reported IVF as a way of conception). Nearly half of both groups are smokers, and 32.7 % of women in the control group and 38.8 % in experimental smoked during pregnancy. Exposure to pesticides reported 50.9 % of mothers in control and 44 % of mothers in the experimental group. Professional exposure was reported by 3 control subjects and 2 subjects in experimental group. The subjects did not differ according to the origin of fruits and vegetables they were consuming, neither regarding the type of fruits they consumed during pregnancy. Average level of dimethylphosphate in control group was 5.604 ± 6.103 ug/L, and in experimental 4.815 ± 6.729 ug/l. Levels of diethylphosphate in control group were 0.408 ± 0.447 ug/L, and in experimental 0.461 ± 0.593 ug/l. DMDTP level in the control group was 0.431 ± 0.508 ug/L, and in experimental 0.547 ± 0570 ug/L, and the DETP was measured 0.403 ± 0.606 ug/L in control, and 0.725 ± 0.529 ug/L in the experimental group. These metabolites showed no statistically significant difference in the examined groups. Similar values are obtained for the adjusted values for creatinine level. Univariate regression analysis showed that the subjects who live in town are 3.3 times more likely to have child with undescended testis, and those who live in the apartment are 2.5 times more likely for the same outcome. Statistically significant difference was noticed in DEDTP level depending on the age of the subject and the living unit. Higher levels of DETP metabolites were detected in subjects that have been on hormonal therapy during pregnancy. The subjects who reported being exposed to pesticides during pregnancy had statistically significantly higher DMDTP values in relation to the subjects that were not exposed to pesticides. Similar results are obtained for the DEDTP level with higher levels in subjects owning pets. Statistically higher levels of DEP and DETP adjusted for creatinine were obtained in subjects that were not reporting eating apples, and higher levels of DEP and DEDTP were obtained in subjects that consumed raspberries and blackberries during pregnancy. Other groups showed no statistically significant difference between the study groups. Conclusion: Exposure of pregnant women to OP pesticides is not significantly greater in the group of mothers who gave birth to children with undescended testis in relation to exposure to OP pesticides in mothers of healthy male children. The level of OP metabolites (dimethylphosphate, dimethyldithiophosphate, diethylphosphate, diethylthiophosphate and diethyldithiophosphate) in the urine of mothers who gave birth to children with undescended testis is not higher in relation to the levels of OP metabolites (dimethylphosphate, dimethyldithiophosphate, diethylphosphate, diethylthiophosphate and diethyldithiophosphate) recorded in urine of mothers who gave birth to healthy male children.
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9

Zeuß, Dominique Victoria [Verfasser]. "Marine Kontamination mit Kunststoffen : mögliche Krebsrisiken beim Menschen über Endokrine oder Epigenetische Disruption? / Dominique Victoria Zeuß". Köln : Deutsche Zentralbibliothek für Medizin, 2013. http://d-nb.info/104515864X/34.

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Bögi, Christian. "Endokrin wirksame Stoffe (endocrine disruptors) und deren Wirkungen auf die Sexualdifferenzierung bei Amphib Xenopus laevis". Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2003. http://dx.doi.org/10.18452/14889.

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Die vorliegende Arbeit befasst sich mit der Erweiterung des etablierten Stu-dienmodells Xenopus laevis zur Untersuchung der Wirkung von endocrine disruptors auf die Reproduktionsbiologie von Amphibien. Um einen Einblick in die grundlegenden Mechanismen der sexuellen Differenzierung von Amphibien zu gewinnen, wurden die Konzentrationen bestimmt, mit denen androgene und estrogene Sexualsteroide während der larvalen Entwicklung in verschiedenen Stadien von Xenopus vorliegen. Parallel wurde das Auftreten der korrespondierenden Rezeptoren im Verlauf der Entwicklung untersucht, über welche die hormonelle Wirkung vermittelt wird. Auf der Basis der gewonnenen Erkenntnisse konnte eine neue Hypothese zur sexuellen Differenzierung von Amphibien entwickelt und vorgestellt werden. Sie stellt das Enzym 5alpha-Reduktase, das die Umwandlung von Testosteron in das potentere und nicht weiter aromatisierbare Androgen Dihydrotestosteron (DHT) bewerkstelligt, in den Mittelpunkt des Prozesses der Geschlechtsdifferenzierung. Abhängig von der genetisch bedingten Expression dieses Enzyms kommt es zu einem höheren oder niedrigeren Auftreten des DHT und damit zu Unterschieden im Verhältnis von DHT zu Estradiol (E2). Der Charakter dieses Verhältnisses scheint der entscheidende Auslöser für die Entwicklung eines weiblichen oder männlichen Phänotyps zu sein. In einem zweiten, anwendungsorientierten Teil wurde untersucht, in wie weit die bislang auf Laboruntersuchungen beschränkte Arbeit mit X. laevis auf Feldstudien erweiterbar ist und ob sich auf diese Weise gewonnene Daten auf die Situation heimischer Amphibien übertragen lassen. Parallele Expositionen des Krallenfrosches einerseits und des Grasfrosches (Rana temporaria) andererseits gegenüber realen Medien unter Freilandbedingungen bestätigten die hervorragende Eignung des Studienmodells X.laevis zur Beurteilung endokriner Belastungssituationen. Darüber hinaus konnte gezeigt werden, dass sich durch die Verwendung von Festphasenextrakten die endokrinen Wirkungen komplexer Matrizes unter standardisierten Laborbedingungen charakterisieren lassen. Rezeptorbindungsstudien sowie Untersuchungen zur Genexpression spezifischer Marker, histologische Betrachtungen von Gonadengewebe und die Bestimmung von Geschlechterverhältnissen ermöglichten Aussagen auf vielfältigen Nachweisebenen. Auf diese Weise konnte das Potenzial, mit dem Proben jeder Art, sowohl durch kurz- als auch durch langfristige Exposition, adverse Effekte auf das amphibische Hormonsystem hervorrufen können, umfassend und differenziert analysiert werden.
The presented work aims to contribute to the various opportunities of studying the effects of endocrine disruption on sexual differentiation in amphibians provided by the well established model Xenopus laevis. In order to gain insight into the basic mechanisms underlying the sexual differentiation in amphibians, the concentrations of androgen and estrogen sexual steroids during several stages of the larval development of Xenopus were determined. In parallel, the ocurrence of the corresponding receptors, which mediate the effects of the respective hormones, was observed. Based on the results of the studies described, a new hypothesis regarding sexual differentiation in amphibians is presented, which assignes the enzyme 5alpha-reductase as the central element of sexual development. This enzyme converts the androgen testosterone into dihydrotestosterone, which can not be aromatized into estradiol. Depending on the genetic sex of the indivual, genexpression of 5a-reductase may differ and therefore lead to a characteristic ratio of androgens and estrogens. We suggest, that this ratio might be the essential trigger for amphibians to develop into a male or a female. A second part aimed to enlarge the Xenopus model to the use in field studies and to proof the transferability of such data to the situation of endemic amphibians. Exposure in parallel of Xenopus on one hand and the green frog Rana temporaria on the other to the effluent of a bavarian wastewater treatment plant revealed the exceeding suitability of the model to asess the endocrine charge of the environment. Furthermore, the use of solid phase extracts derived from natural samples allowed the characterization of the respective endocrine potential under standardized laboratory conditions. Rezeptor binding studies, detection of genexpression of specific biomarkers, histological examination of gonadal tissue and the determination of sex ratios provided the evaluation of effects on several levels of investigation. By this means the Xenopus model offers the opportunity to assess the ability of any kind of sample to cause endocrine impacts on amphibians after short time as well as after long time exposure in a broad and at the same time differentiated way.
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Viljoen, Ignatius Michael. "Possible endocrine disruption in molluscs from the Limpopo Province / Ignatius Michael Viljoen". Thesis, North-West University, 2010. http://hdl.handle.net/10394/4510.

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With parts of SA in a malaria endemic area, a preventative way of fighting malaria is with the use of pesticides such as 1,1,1–Trichloro–2,2–bis(pclorophenyl) ethane, also known as DDT. DDT is listed under the persistent organic pollutants (POPs) and considered an endocrine disruptive compound (EDC) under the Stockholm Convention. SA registered an exemption to use DDT as means to fight malaria. DDT and its isomers are, however, known EDCs. Combined with their ability to persist in the environment while not being target specific motivates further studies into possible detrimental effects. The present study aimed to establish if ED was present by comparing the male reproductive organs from snails from an area currently sprayed with DDT (for malaria control) to an area not sprayed with DDT in the Limpopo Province. A possible endpoint (the penis sheath/preputium length ratio or PSPLR) was identified for the freshwater snail Bulinus tropicus. B. tropicus and sediment samples were collected from DDT–sprayed and nonsprayed areas located close together. The snails were dissected and various morphometric parameters measured. Sediments from the sites where the snails were collected were analysed for DDT using GC–MS. Statistical analysis showed significant differences in PSPLR (and therefore possible ED) between snails from the two areas. The difference in PSPLR values was mainly due to a relatively shorter preputium for the snails from the DDT–sprayed area. Even though the sediment samples showed that DDT was present in most of the DDT–sprayed sites and not in the non–DDT sprayed sites, causality of the possible ED could not be established from this field study. This study indicated the possibility of using the PSPLR as endpoint for ED. Recommendations are made for further development of the PSPLR and B. tropicus as biological indicators for endocrine disruption, but causality must first be established.
Thesis (M.Sc (Environmental Science))--North-West University, Potchefstroom Campus, 2011.
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12

Reder, Sabine. "Multi-Analyt-Bestimmung von endokrinen Disruptoren im Wasser mit Hilfe eines Fluoreszenz-Immunoassays unter Verwendung von neuronalen Netzen". [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=966590414.

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Dragana, Bosić-Živanović. "Uticaj ftalata iz spoljašnje sredine na neke metaboličke poremećaje". Phd thesis, Univerzitet u Novom Sadu, Medicinski fakultet u Novom Sadu, 2015. http://www.cris.uns.ac.rs/record.jsf?recordId=93650&source=NDLTD&language=en.

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Uvod. Ftalati su endokrini disruptori, široko se koriste kao plastifikatori, rastvarači i aditivi u mnogim potrošačkim proizvodima. Eksperimentalni podaci i humane studije sugerišu na povezanost ftalata sa gojaznošću i dijabetesom. Cilj. Utvrditi da li su i koji urinami metaboliti ftalata prisutni i da li postoje razlike u njihovim nivoima između bolesnika s tipom 2 šećeme bolesti, gojaznih i kontrolne grupe zdravih osoba; da li postoji povezanost između metabolita ftalata i gojaznosti, lipida i lipoproteina seruma, glikemije, insulinemije i insulinske rezistencije.Metode. Istraživanje je obuhvatilo 305 ispitanika, podeljenih u 3 grupe: gojazni (n=104), dijabetesni bolesnici tip 2 (n=101) i zdrave osobe (n=100), oba pola. U svih ispitanika su izvršena antropometrijska merenja (BMI i obim struka), određivanje serumskih lipida (ukupni holesterol, trigliceidi, HDL i LDL holesterol), te glikemija, insulinemija i izračunat indeks insulinske rezistencije (HOMA IRI). U jutarnjem uzorku urina meren je nivo 10 ftalatnih metabolita: mono-metil ftalat (MMP), mono-etil ftalat (MEP), mono-n-butil ftalat (MnBP), mono- benzil ftalat (MBzP), mono-cikloheksil ftalat (MCHP), mono-n-propil ftalat (MPP), mono-n-amil ftalat (MnAP), mono-izo-amil ftalat (MiAP), mono- n-oktil ftalat (MOP), mono-2-etilheksil ftalat (MEHP). U odnosu na prisustvo ftalata u urinu svaka grupa je podeljena u podgrupe na one sa prisutnim ftalatima i one bez ftalata u urinu, odnosno na podgrupe MEP pozitivne, MEP negativne, MEHP pozitivne i MEHP negativne. Rezultati. Kod polovine ispitanika registrovali smo prisustvo u urinu pojedinih metabolita ftalata. Najčešći su bili MEHP i MEP. Najveća sličnost u nivou MEP-a i MEHP-a je bila između gojaznih i dijabetesnih ispitanika. U odnosu na antropometrij ske parametre uočena je pozitivna korelacija MEP-a sa BMI i obimom struka, a negativna korelacija MEHP-a sa BMI i obimom struka, ali su bile nesignifikantne. Samo kod MEHP pozitivnih kontrolne grupe uočena je statistički značajna pozitivna korelacija MEHP-a i obima struka. Utvrđena je statistički značajna negativna korelaciju MEP-a i HDL holesterola, a pozitivna korelacija MEP-a i triglicerida samo kod gojaznih. Samo u kontrolnoj grupi MEHP pozitivnih postojala je statistički značajna negativna korelacija sa HDL holesterolom. Postojala je pozitivna korelacija MEP-a i HOMA-IRI, a pozitivna korelacija MEHP-a sa glikemijom samo kod MEHP pozitivnih DM tip 2. Zaključak. Potvrđeno je da je kontaminacija ftalatima prisutna u našoj populaciji, a najčešće su prisutni MEHP i MEP, ukazujući na ekspoziciju DEHP i DEP. Indirektno smo stekli uvid da povećana izloženost DEP i DEHP može doprineti nastanku izvesnih poremećaja lipida i lipoproteina, insulinskoj rezistenciji kao i razvoju gojaznosti.
Introduction. Phthalates are endocrine disruptors, widely used as plasticizers, solvents and additives in a wide range of consumer products. Experimental data and human studies suggest that phthalate exposure is linked with obesity and diabetes. Aim. To determine whether urinary phthalate metabolites are present, which ones are present, whether there are differences between their levels among the patients with type 2 diabetes, obesity patients and a control group of healthy individuals; whether there is a link between phthalate metabolites and obesity, lipids, serum lipoproteins, glycemia, insulinemia and insulin resistance. Methods. The research included 305 participants divided into three groups: obesity patients (n=104), type 2 diabetes patients (n=101) and healthy individuals (n=100) in both sexes. Anthropometric measurements were taken from all participants (BMI and waist circumference), as well as measurement of serum lipids (total cholesterol, triglycerides, HDL and LDL cholesterol), glycemia, insulinemia and a calculation of insulin resistance index (HOMA IRI). The levels of ten phthalate metabolites weremeasured in a morning sample of urine: Mono-methyl phthalate (MMP), Mono-ethyl phthalate (MEP), Mono-n-butyl phthalate (MnBP), Mono-benzyl phthalate (MBzP), Mono- cyclohexyl phthalate (MCHP), Mono-n-propyl phthalate (MPP), Mono-n-amyl phthalate (MnAP), Mono-iso-amyl phthalate (MiAP), Mono-n-octyl phthalate (MOP), Mono-2- ethylhexyl phthalate (MEHP). Regarding the presence of phthalates in urine, each group was divided into subgroups, containing phthalates and or not containing phthalates, i.e. subgroups MEP positive and MEP negative, MEHP positive and MEHP negative. Results. In a half of participants, we have registered the presence of certain phthalate metabolites in urine, most often MEHP and MEP. The highest similarity in the levels of MEHP and MEP was between obesity and diabetes participants. Regarding anthropometric measurements, positive correlation has been registered between MEP and BMI and waist circumference, while negative correlation has been registered between MEHP and BMI and waist circumference, but it was insignificant. Only in MEHP positive control group, statistically significant positive correlation between MEHP and waist circumference has been registered. Statistically significant negative correlation between MEP and HDL cholesterol has been registered, while positive correlation between MEP and triglycerides has been registered only in obesity patients group. Only in MEHP positive control group statistically significant negative correlation with HDL cholesterol has been registered. There has been a positive correlation between MEP and HOMA-IRI, while positive correlation between MEHP and glycemia has been registered only in MEHP positive DM type 2. Conclusion. It has been confirmed that our population is contaminated with phthalates, most commonly MEHP and MEP, indicating exposure to DEHP and DEP. Indirectly, we have realized that an increased exposure to DEHP and DEP can contribute to the development of certain lipid and lipoprotein disorders, insulin resistance, as well as the development of obesity.
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14

Nobis, Inga [Verfasser]. "Wirkung ausgewählter endokriner Disruptoren auf T3-regulierte Endpunkte in der Hypothalamus-Hypophysen-Schilddrüsenhormonachse und verschiedene von ihr regulierte Enzyme / Inga Nobis". Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2009. http://d-nb.info/1023704072/34.

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Litvinov, Vitali [Verfasser], Wolfgang [Akademischer Betreuer] Wuttke y Paul [Akademischer Betreuer] Thelen. "Wirkungen endokriner Disruptoren auf Prostata und Samenblase der Sprague-Dawley-Ratte / Vitali Litvinov. Gutachter: Wolfgang Wuttke ; Paul Thelen. Betreuer: Wolfgang Wuttke". Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2012. http://d-nb.info/1043509127/34.

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Hintemann, Therese. "Entwicklung, Optimierung, Validierung und Automatisierung eines Immunoassays zur sensitiven Detektion des endokrinen Disruptors 17[beta]-Östradiol [17-Beta-Östradiol] im Wasserkreislauf /". Bonn : Inst. für Nutzpflanzenwiss. und Ressourcenschutz, 2007. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=016669810&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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17

Bredhult, Carolina. "Effects of some Endocrine Disruptors on Human and Grey Seal Uterine Cells". Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8334.

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Scheider, Jessica [Verfasser], Jörg [Akademischer Betreuer] Oehlmann, Jörg [Gutachter] Oehlmann y Sven [Gutachter] Klimpel. "Entwicklung einer Tierversuchsersatzmethode für endokrine Disruptoren - Grundlagenuntersuchungen am Hühnerembryo / Jessica Scheider ; Gutachter: Jörg Oehlmann, Sven Klimpel ; Betreuer: Jörg Oehlmann". Frankfurt am Main : Universitätsbibliothek Johann Christian Senckenberg, 2020. http://d-nb.info/1220774839/34.

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19

Hilgendorf, Leonie [Verfasser], Wolfgang [Akademischer Betreuer] Wuttke, Hubertus [Akademischer Betreuer] Jarry y Carsten [Akademischer Betreuer] Gründker. "Östrogenes Potential des endokrinen Disruptors 4-MBC im Reproduktionstrakt von ovariektomierten Ratten / Leonie Hilgendorf. Gutachter: Hubertus Jarry ; Carsten Gründker. Betreuer: Wolfgang Wuttke". Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2011. http://d-nb.info/1042348324/34.

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20

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.

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Hormonell wirksame Chemikalien, wie Pflanzenschutzmittel oder Pharmaka gelangen durch Abwässer in die Umwelt und akkumulieren vor allem in Oberflächengewässern. Ein erhöhtes Augenmerk liegt auf Substanzen, die durch (anti)androgene und (anti)östrogene Wirkungsweise die Reproduktion von Tieren und Menschen beeinträchtigen. Bei den bisherigen Nachweismethoden für diese Stoffe handelt es sich um invasive Methoden, die das Töten der Tiere beinhalten. Diesen Methoden mangelt es jedoch an der nötigen Sensitivität, um umweltrelevante Konzentrationen der endokrinen Disruptoren (EDs) nach Kurzzeitexposition nachweisen zu können, sowie am Vermögen, alle vier Wirkmechanismen (androgen, antiandrogen, östrogen und antiöstrogen) mit einer einzelnen Testmethode feststellen und unterscheiden zu können. In dieser Studie wurde deshalb mit Hilfe männlicher Afrikanischer Krallenfrösche (Xenopus laevis) eine Testmethode entwickelt, bei der die Frösche verschiedenen (anti)androgenen und (anti)östrogenen EDs ausgesetzt wurden und ihr Rufverhalten untersucht wurde. Diese nicht-invasive Methode erwies sich als schnell und höchst sensitiv. Zudem war es erstmals möglich, die vier verschiedenen Wirkmechanismen allein anhand veränderter Ruftypen und Rufparameter zu bestimmen und zu unterscheiden. Darüber hinaus konnte gezeigt werden, dass bei Anwendung dieser Methode die Möglichkeit besteht, die Versuchstiere in weiteren Tests wiederzuverwenden, da die Rufparameter nach einer expositionsfreien Zeit von sechs Wochen wieder Kontrollwerte erreichten. Zusammengefasst kann die hier vorgestellte verhaltensphysiologische und damit nicht-invasive Methode als Biomarker für den Nachweis von (anti)androgenen und (anti)östrogenen EDs verwendet werden. Ferner zeigt die hohe Sensitivität des Tests, sowie die Möglichkeit der vollautomatischen Analyse enormer Datenmengen, dass dieser schnelle Verhaltenstest ein großes Potential hat, ein sensitiver, standardisierter und nicht-invasiver Biomarker zu werden.
Endocrine 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.
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Vossmann, Vera [Verfasser], Wolfgang [Akademischer Betreuer] Wuttke y Carsten [Akademischer Betreuer] Gründker. "Wirkung von Endokrinen Disruptoren auf die Tibiametaphyse der ovarektomierten Sprague-Dawley-Ratte / Vera Vossmann. Gutachter: Wolfgang Wuttke ; Carsten Gründker. Betreuer: Wolfgang Wuttke". Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2011. http://d-nb.info/1042732914/34.

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Klinker, Friederike E. [Verfasser], Wolfgang [Akademischer Betreuer] Wuttke, Jörg [Akademischer Betreuer] Männer, Paul [Akademischer Betreuer] Thelen y Martin [Akademischer Betreuer] Oppermann. "Die Effekte von endokrinen Disruptoren auf den Herzmuskel orchidektomierter Ratten / Friederike E. Klinker. Gutachter: Jörg Männer ; Paul Thelen ; Martin Oppermann. Betreuer: Wolfgang Wuttke". Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2014. http://d-nb.info/1050873084/34.

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Schmidt, Juliane-Susanne Verfasser], Bernd [Akademischer Betreuer] [Fischer, Gabriele [Akademischer Betreuer] Stangl y Hubertus [Akademischer Betreuer] Jarry. "Einfluss der endokrinen Disruptoren DEHP und PCB auf Fertilität und Adipositasentwicklung weiblicher Mäuse / Juliane-Susanne Schmidt. Betreuer: Bernd Fischer ; Gabriele Stangl ; Hubertus Jarry". Halle, Saale : Universitäts- und Landesbibliothek Sachsen-Anhalt, 2014. http://d-nb.info/1068809728/34.

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Bögi, Christian. "Endokrin wirksame Stoffe (endocrine disruptors) und deren Wirkungen auf die Sexualdifferenzierung bei Amphib Xenopus laevis Untersuchungen in vitro, in vivo und im Freiland /". [S.l.] : [s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=968749658.

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Siegel, 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.

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Estrogen compounds are a subgroup of the environmental pollutants named Endocrine Disrupting Chemicals. It is a large group of chemicals which are capable of causing hormonal imbalance of an organism and affecting its reproductive, developmental or behavioral functions. In the environment, they are found in very low concentrations (below ng/l). This makes their detection and elimination highly problematic. The Research Centre for Toxic Compounds in the Environment (RECETOX) has been developing an experimental device which employes reverse osmosis (RO) to concentrate the trace amounts of micropollutants (e.g. estrogens). The aim is to lower the detection limit of subsequent analytical methods. RO seems to be a promising alternative to commonly used methods which are more time consuming and costly. The aim of this thesis is to create a mathematical model of RO, which would describe the process of estrogen concentration and therefore could contribute to the optimization of experimental device. The mathematical model was created in MATLAB-simulink and verified by comparison to thirteen experimental results. The solutions used to test the model were NaCl at 0.002–2 g/l and drinking water with 17-ethinylestradiol of 25 ng/l. In order to concentrate the retentate on a flat-sheet RO membrane the model achieves a mean relative error in the range of 0.9–4.9 % for NaCl and drinking water. For the concentration of estrogens the deflection is 3.6 %. Comparing the model and experimental concentration of NaCl on a spiral wound RO-membrane, the deviation is in the range of 5.9–8.7 %. So far, ratio of retentate volume from the beginning to the end of the process has been used to determine the process recovery. However, due to the results obtained in the thesis, this approach appears inaccurate. A more accurate recovery would likely be achieved by using the theoretical concentration value obtained by the proposed mathematical model. However, to increase reliability, the further measurements with estrogens are needed, and also to determine the causes of deflection of model and experimental retentate volume values at the end of the concentration
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Bögi, Christian [Verfasser], Andreas [Gutachter] Elepfandt, Jörg [Gutachter] Oehlmann y Werner [Gutachter] Kloas. "Endokrin wirksame Stoffe (endocrine disruptors) und deren Wirkungen auf die Sexualdifferenzierung bei Amphib Xenopus laevis / Christian Bögi ; Gutachter: Andreas Elepfandt, Jörg Oehlmann, Werner Kloas". Berlin : Humboldt-Universität zu Berlin, 2003. http://d-nb.info/120766457X/34.

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Andrijana, Milankov. "Povezanost estara ftalne kiseline i sindroma policističnih jajnika". Phd thesis, Univerzitet u Novom Sadu, Medicinski fakultet u Novom Sadu, 2019. https://www.cris.uns.ac.rs/record.jsf?recordId=108382&source=NDLTD&language=en.

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Uvod: Ftalati su vrsta endokrinih disruptora koji se široko koriste kao plastifikatori i rastvarači ali i kao aditivi brojim proizvodima koji se svakodnevno koriste. Prema dosadašnjim studijama na eksperimentalnim životinjama, ali i u humanoj populaciji, diestri ftalne kiseline utiču na reproduktivni sistem, učestvuju u nastanku insulinske rezistencije i gojaznosti. Sindrom policističnih ovarijuma (PCOS) je najčešći endokrinološki poremećaj reproduktivnog sistema žena u generativnom periodu. Insulinska rezistencija i centralna gojaznost, kao faktori kardiometaboličkog sindroma imaju značajnu ulogu u etiologiji PCOS. Ciljevi: Utvrditi prisustvo metabolita ftalne kiseline kod žena u reproduktivnom periodu u našoj sredini, kao i da li postoji povezanost ovih endokrinih disruptora sa antropometrijskim parametrima, parametrima glikoregulacije, lipidima i lipoproteinima seruma, gonadotropinima, polnim hormonima, leptinom i indeksima kardiometaboličkog rizika kod žena sa sindromom policističnih jajnika. Metode: Istraživanje je obuhvatalo 61 ženu sa sindromom policističnih jajnika koje su podeljene u dve podgrupe: 31 ispitanica sa PCOS i prisutnim ftalatnim metabolitima u urinu i 30 ispitanica sa PCOS bez ftalatnih metabolita u urinu. Kontrolnu grupu je činilo 30 zdravih žena. Kod svih ispitanica vršena su antropometrijska merenja (TV, TM, OS) i određivane vrednosti parametara glikoregulacije (glikemija i insulinemija, izačunat je HOMA index), lipidi i lipoproteini seruma (ukupan holesterol, trigliceridi, LDL i HDL holesterol), gonadotropini (LH i FSH), polni hormoni (estradiol i testosteron) i leptin. U proceni kardiometaboličkog rizika korišćena su dva indeksa LAP i VAI. Iz jutarnjeg uzorka urina određivano je prisustvo i koncentracija 10 ftalatnih metabolita: Mono-metil ftalat- MMP, Mono-etil ftalat - MEP, Mono-n-butil ftalat - MBP, Mono-n-propil ftalat- MPP, Mono-izo-amil ftalat - MiAP, Mono-n-amil ftalat - MnAP, Mono-cikloheksil ftalat - MCHP, Monobenzil ftalat- MBzP, Mono-(2-etilheksil) ftalat- MHEP, Mono-n-octil ftalat-MOP. Za statističku obradu podataka korišćeni su odgovarajući parametarski i neparametarski testovi. Rezultati: Kod 51 % ispitanica sa PCOS potvrđeno je prisustvo ftalatnih metabolita u urinu. Najzastupljeniji ftalatni metabolit je bio MEHP, zatim MEP, ali je potvrđeno i prisustvo MMP, MPP i MOP. Kod ispitanica sa PCOS su potvrđene statistički značajne korelacije između ukupnih ftalatnih metabolita i BMI, obima struka, glikemije, insulinemije, HOMA indeksa, ukupnog holesterola, triglicerida, LDL holesterola, leptina i testosterona. Analizom pojedinačnih ftalatnih metabolita utvrđene su pozitivne korelacije između MMP i obima struka, parametara glukoznog metabolizma, ukupnog holesterola, LDL holesterola, triglicerida, LAP i VAI indeksa. Zaključak: Kod žena sa PCOS u reproduktivnom periodu u našoj sredini je potvrđeno prisustvo ftalanih metabolita. Najviše koncentracije su verifikovane za MEHP i MEP, ukazujući na visoku ekspoziciju di-etilheksil ftalatu (DEHP) i di-etil ftalatu (DEP). Ukupni ftalati značajno povećavaju vrednosti parametara koje učestvuju u razvoju metaboličkog sindroma kod PCOS, ali i povećavaju kardiovaskularni rizik ovih bolesnica. Direktna, značajna veza je potvrđena između MMP i testosterona, parametara i indeksa kardiometaboličkog sindroma.
Introduction: Phthalates are a type of endocrine disruptor widely used as plasticizers and solvents but also as additives to many products that are used daily. According to previous studies in experimental animals, but also in the human population, phthalic diesters affect the reproductive system, participate in the onset of insulin resistance and obesity. Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder of the reproductive system of women in the generative period. Insulin resistance and central obesity, as factors of cardiometabolic syndrome, have a significant role in the etiology of PCOS. Objectives: To determine the presence of phthalic acid metabolites in women in the reproductive period in our environment, and whether there is a connection between these endocrine disruptors with anthropometric parameters, glycoregulation parameters, lipids and serum lipoproteins, gonadotrophins, sex hormones, leptin and indexes of cardiometabolic risk in women with polycystic ovarian syndrome. Methods: The study included 61 women with polycystic ovarian syndrome divided into two subgroups: 31 subjects with PCOS and present phthalate metabolites in urine and 30 subjects with PCOS without phthalate metabolites in urine. The control group consisted of 30 healthy women. In all subjects, anthropometric measurements were carried out (TV, TM, WC) and the values of glycoregulation parameters (glycemia and insulinemia, HOMA index), lipids and serum lipoproteins (total cholesterol, triglycerides, LDL I HDL cholesterol), gonadotropins FSH), sex hormones (estradiol and testosterone) and leptin. In the assessment of cardiometabolic risk LAP and VAI indexes were determined. From the morning urine sample, the presence and concentration of 10 phthalate metabolites were determined: Mono-methyl phthalate-MMP, Mono-ethyl phthalate-MEP, Mono-n-butyl phthalate-MBF, Mono-n- propyl phthalate- MPP, Mono-iso-amyl phthalate – MiAP, Mono-n-amyl phthalate – MnAP, Mono-cyclohexyl phthalate-MCHP, Monobenzyl phthalate-MBzP, Mono- (2-ethylhexyl) phthalate-MHEP, Mono-n-octyl phthalate-MOP. For statistical data processing, appropriate parametric and non-parametric tests were used. Results: 51% of subjects with PCOS confirmed the presence of phthalate metabolites in urine. The most common phthalate metabolite was MEHP, then MEP, but the presence of MMP, MPP and MOP also was confirmed. In subjects with PCOS, a statistically significant correlations between total phthalate metabolites and BMI, waist circumference, glycemia, insulinemia, HOMA index, total cholesterol, triglyceride, LDL cholesterol, leptin and testosterone were confirmed. By analyzing individual phthalate metabolites, a positive correlations between MMP and waist circumference, glycoregulation parameters, total cholesterol, LDL cholesterol, triglyceride, testosterone and LAP and VAI index were determined. Conclusion: In women with PCOS in the reproductive period, the presence of phthalic metabolites in our environment was confirmed. The highest concentrations were verified for MEHP and MEP, indicating a high exposure of DEHP and DEP. Total phthalates significantly increase the values of parameters involved in the development of metabolic syndrome in PCOS, but also increase the cardiovascular risk of these patients. A direct, significant association was confirmed between MMP and testosterone, parameters and index of cardiometabolic syndrome.
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Titzmann, Adriana [Verfasser], Peter [Akademischer Betreuer] Fasching y Peter [Gutachter] Fasching. "Ernährungsformen in der Schwangerschaft – Einfluss von Ernährungsmustern mit hohem Expositionsrisiko für endokrine Disruptoren auf den Schwangerschaftsverlauf und Geburtsparameter / Adriana Titzmann ; Gutachter: Peter Fasching ; Betreuer: Peter Fasching". Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2021. http://d-nb.info/1235224597/34.

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Ladewig, Vanessa. "Der Einfluss von hormonell wirksamen Umweltchemikalien auf die Populationsökologie von Gammarus fossarum". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2004. http://nbn-resolving.de/urn:nbn:de:swb:14-1094121391765-54938.

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Bei zwei Fließgewässern (Lockwitzbach und Körsch) wurde ein Expositions- und Effektmonitoring an Probenahmestellen jeweils ober- und unterhalb des Einleiters eines kommunalen Klärwerks über einen Zeitraum von zwei Jahren durchgeführt. Gegenstand der vorliegenden Arbeit waren dabei die Untersuchungen zur Populationsstruktur und -dynamik von Gammarus fossarum (Amphipoda, Crustacea). Folgende Populationsvariablen wurden erfasst: Abundanz, Geschlechterverhältnis, Anteil von Juvenilen, Anteil brütender Weibchen, Fekundität, Körperlängen und Infektion mit Acanthocephalen. Erstmalig wurde Intersexualität bei G. fossarum festgestellt. Im Lockwitzbach war der Anteil an Intersexen bei den adulten Gammariden mit etwa 5 - 15 % höher als in der Körsch mit < 1 %. Intersexualität wurde nicht durch die Einleiter induziert. Bei den Intersexen handelt es sich um funktionelle Weibchen. Wodurch dieses Phänomen ausgelöst wird und welche Bedeutung es für die Population hat, ist unbekannt. In den Freilanduntersuchungen wurden im Projekt Xehogamm (Umweltbundesamt Berlin, FKZ 299 65 221/05), in dessen Rahmen diese Dissertation entstand, verschiedene Umweltchemikalien im Bachwasser analysiert. Bei Vertebraten ist eine östrogene Wirksamkeit dieser Substanzen bekannt oder wird vermutet. In den Gammaridenpopulationen unterhalb der Klärwerkseinleiter waren wichtige populationsrelevante Variablen im Vergleich zu oberhalb verändert. An der unteren Probenahmestelle bei der Körsch war der Anteil der Juvenilen mit der kleinsten Körperlänge sowie der Anteil brütender Weibchen erniedrigt. Tendenziell traf dies auch für die untere Probenahmestelle beim Lockwitzbach zu. Bei der Körsch ist außerdem der frühere Beginn der herbstlichen Reproduktionspause und die geringere Körperlänge adulter Gammariden möglicherweise auf endokrine Umweltchemikalien im Wasser des Einleiters zurückzuführen. Von den nachgewiesenen Substanzen wurde eine Einzelsubstanz, Bisphenol A, für ein Fließrinnenexperiment ausgewählt. In künstlichen Fließrinnen im Gewächshaus wurde G. fossarum paarweise, in Gruppen sowie als größenstrukturierte Population in der Fließrinne selbst über 103 Tage exponiert, und verschiedene Populationsvariablen wurden erfasst. Die Nominalkonzentrationen von Bisphenol A in drei Fließrinnen betrugen 5, 50 und 500 µg/L. In den ersten drei aufeinanderfolgenden Bruten zeigte sich in der höchsten Bisphenol A-Konzentration die größte Brutgröße. Im weiteren Verlauf des Experiments übte Bisphenol A einen hemmenden Einfluss auf die Reproduktion der Gammariden aus. Basierend auf den Nominalkonzentrationen wurden folgende EC10-Werte berechnet: Anteil reproduzierender Weibchen für die 4. Brut (bei Gammaridenpaaren): 22 µg/L, Brutgröße der 4. Brut (bei Gammaridenpaaren): 11 µg/L, Anteil brütender Weibchen (Population): 212 µg/L und Anteil Juveniler (Population): 153 µg/L Bisphenol A. Die EC10-Werte basierend auf Effektivkonzentrationen für dieselben Endpunkte betragen: bei den Paaren 1,1 µg/L (reproduzierende Weibchen) und 0,5 µg/L (Brutgröße), in der Population 10 µg/L (Anteil brütender Weibchen und Anteil Juveniler). Im Fließrinnenexperiment wurde Bisphenol A zwar in höheren Konzentrationen als im Freiland vorhanden eingesetzt, die beobachteten Effekte weisen jedoch in dieselbe Richtung wie die Effekte im Freiland. Daher kann nicht ausgeschlossen werden, dass auch die Effekte im Freiland auf einer endokrinen Wirkung von Umweltchemikalien beruhen könnten. Zusätzlich wurde der Einfluss von Bisphenol A auf die Osmoregulation bei G. lacustris untersucht, wobei unterschiedliche Effekte auf die Natrium- und Calciumkonzentration, nicht jedoch auf die Osmolalität, in der Hämolymphe nachgewiesen wurden. Anlage: Rohdaten (3,87 MB)- Nutzung: Referat Informationsvermittlung der SLUB
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Tamschick, Stephanie. "Sex-linked molecular markers and their application to endocrine disruption research in amphibians". Doctoral thesis, Humboldt-Universität zu Berlin, Lebenswissenschaftliche Fakultät, 2016. http://dx.doi.org/10.18452/17649.

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Die weltweit mehr als 7500 Amphibienarten sind durch anthropogene Ursachen wie Habitatzerstörung, Krankheitsverbreitung, Klimawandel und Umweltverschmutzung in ihrem Bestand bedroht. Einige der Ursachen sind kaum erforscht, so die Verschmutzung aquatischer Ökosysteme durch endokrine Disruptoren (EDs), Substanzen, die mit dem Hormonsystem interagieren. Ausgehend von neuen molekularen Markern, welche die Ermittlung des genetischen Geschlechts erstmals bei einigen Hyliden und Bufoniden erlauben, wurde in der vorliegenden Arbeit auf die Wirkung des synthetischen Östrogens 17α- Ethinylestradiol (EE2)und des Weichmachers Bisphenol A (BPA) fokussiert. Für drei Bufonidenarten wurde zunächst die Geschlechtsgebundenheit von Mikrosatelliten getestet und ein XX/XY-System nachgewiesen. Diese und bereits etablierte Marker wurden anschließend in ein neu entwickeltes Versuchsdesign für ED-Studien integriert: Nach gleichzeitiger Aufzucht von Modell- (Xenopus laevis) und Nicht-Modell-Arten (Hyla arborea, Bufo viridis) unter EE2- bzw. BPA- Exposition wurde das genetische Geschlecht bestimmt und mit dem anatomisch und histologisch ermittelten phänotypischen Geschlecht erglichen. Die drei Anuren zeigten starke Empfindlichkeitsunterschiede gegenüber beiden EDs. Umweltrelevante Konzentrationen beeinflussten die somatische Entwicklung und führten zu artspezifischen Gonaden-Fehlbildungen. EE2 bewirkte zahlreiche partielle und komplette Geschlechtsumwandlungen, mit stärkeren Effekten bei X. laevis. Diese Arbeit zeigt somit, dass bereits niedrige EE2- und BPA-Konzentrationen zu starken Schädigungen führen können und die Substanzen aufgrund ihrer erheblichen aquatischen Präsenz als ernstzunehmende Faktoren der Amphibienkrise anzusehen sind. Die Ermittlung des genetischen Geschlechts wird als wichtig eingestuft, um verlässliche Aussagen über ED-Effekte zu treffen. Zudem sollten an der Modell-Art X. laevis gewonnene Erkenntnisse nicht vorbehaltlos auf andere Amphibienarten extrapoliert werden.
The more than 7500 known amphibian species are globally threatened, mainly due to anthropogenic causes like habitat destruction, dispersing diseases, climate change and environmental pollution. Some of the causes are barely investigated, e.g. the pollution of aquatic ecosystems with endocrine disrupting compounds (EDCs), substances that interfere with the hormone system. Based on new molecular markers, for the first time allowing genetic sexing in some hylids and bufonids, this thesis focused on the effects of the synthetic estrogen 7α-ethinylestradiol(EE2) and the plasticizer bisphenol A (BPA). Initially, several microsatellite markers were tested for sex-linkage in three bufonid species, and an XX/XY system could be revealed. Subsequently, these and other established markers were integrated into a newly developed experimental design for EDC-research: after simultaneous exposure of model (Xenopus laevis) and non-model species (Hyla arborea, Bufo viridis) to EE2 or BPA, metamorphs were genetically sexed. Anatomically and histologically determined phenotypic sexes were directly compared with the genetic sex of each individual. The three anurans showed striking differences in their susceptibilities in both EDCexperiments. Environmentally relevant concentrations affected the somatic development and led to species-specific gonadal anomalies. In addition, EE2 provoked high numbers of mixed sex and completely sex-reversed individuals, with more pronounced effects in X. laevis than in the two non-model species. This work shows that low concentrations of EE2 and BPA lead to severe damages. Due to their widespread presence in the aquatic environment, these substances might contribute to the worldwide amphibian crisis. To produce reliable results in EDC-studies, genetic sexing is considered important. Furthermore, findings gained with the model species X. laevis should not unreservedly be extrapolated to other amphibian species.
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Ivana, Bajkin. "Uticaj estara ftalne kiseline na tiroidnu funkciju". Phd thesis, Univerzitet u Novom Sadu, Medicinski fakultet u Novom Sadu, 2016. http://www.cris.uns.ac.rs/record.jsf?recordId=100256&source=NDLTD&language=en.

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Uvod: Poslednjih godina u fokusu istraživača je efekat sintetskih jednjenja na endokrini sistem. Estri ftalne kiseline se koriste u procesu plastifikacije, kao industrijski rastvarači, lubrikanti, aditivi u tekstilnoj industriji, u pesticidima, kozmetičkim proizvodima. Raste broj dokaza da je tiroidna žlezda podložna dejstvu endokrinih disruptora. Tiroidni hormoni imaju važnu ulogu u regulaciji rasta, tkivne diferencijacije, energetskog metabolizma, reprodukcije i formiranja centralnog nervnog sistema. Brojna istraživanja ukazala su da ftalati deluju kao EDs. Ciljevi istraživanja: 1. Procena izloženosti populacije mono-etilheksil-ftalatu (MEHP) i mono-etil-ftalatu (MEP). 2. Evaluacija razlika u nivou pokazatelja tirodine funkcije između ftalat pozitivnih i ftalat negativnih ispitanika i između gojaznih i normalno uhranjenih ftalat pozitivnih ispitanika. 3.Utvrđivanje razlika u serumskom nivou leptina gojaznih ispitanika sa i bez pozitivnih ftalatnih metabolita i procena povezanosti leptina sa MEP i MEHP i pokazateljima tiroidne funkcije. Izbor ispitanika i metod rada: Istraživanje je sprovedeno kao studija preseka, obuhvatilo je 201 ispitanika. Ispitanici su podeljeni u grupu MEP/MEHP pozitivnih i negativnih i na podgupe normalno uhranjenih i gojaznih. Od antropometrijskih mera određena je telesna visina, telesna masa, obim struka i indeks telesne mase. Laboratorijske analize: jutarnji uzorak urina za određivanje MEP i MEHP; našte uzet uzorka venske krvi za FT4, FT3, TSH i leptin. Statististička analiza sprovedena je na softverskom paketu SPSS. Rezultati: Polovina stanovništva je izložena ftalatima. MEP dovodi do povišenja FT4 samo u subpopulaciji gojaznih. Nije utvrđen statistički značajan uticaj MEP na FT3. Kod gojaznih MEP pozitivnih osoba ženskog pola povišen je TSH. MEHP uzrokuje sniženje FT4 kod normalno uhranjenih ispitanika, a kod normalno uhranjenih muškaraca snižava FT3. Nije utvrđen uticaj MEHP na tirotropin. U gojaznih nije ustanovljen uticaj DEHP i DEP na leptinsku sekreciju.Uočena je tendencija negativne korelacije leptina i FT4 kod gojaznih, dok uticaja na FT3 i TSH nema. Zaključak: Naša populacija je u velikoj meri izložena ftalatima. Potvrđeno je da MEP i MEHP imaju uticaj na pojedine indikatore tiroidne funkcije. Ftalati u našem istraživanju ne uzrokuju poremećaj leptinske skrecije, a leptin ima blag uticaj jedino na FT4.
Introduction: Effects of synthesized chemicals on endocrine system has been in the focus in the last years. Phthalates are used in plasticization, as industrial solvents, lubricants, textile industry additives, in pesticides and cosmetic products. Evidence for thyroid disruption is growing. Thyroid hormones (TH) have an important role in regulation of growth, tissue differentiation, energy metabolism, reproduction and central nervous system formation. Studies show phthalates can cause endocrine disruption. Aims: 1. Estimation of burden of mono-ethyl phthalate (MEP) and di-2-ethylheksyl phthalate(MEHP) in the population. 2. Evaluation of differences in TH and TSH in MEP/MEHP positive and negative participants, as in obese and lean MEP/MEHP positive participants. 3. Evaluation of differences in leptin in obese MEP/MEHP positive and negative subjects and evaluation of the connection between leptin, MEP, MEHP and thyroid indicators. Patients and methods: This was a cross-sectional study that comprised 201 subjects divided into MEP/MEHP positive and negative group, further subdivided in obese and lean. Anthropometric parameters done: body height, body weight, waist and body mass index. Laboratory tests done: morning urine sample analysis for MEP/MEHP and venous sample analysis for free thyroxine (FT4), free tri-iodothyronine (FT3), thyroid stimulating hormone (TSH) and leptin. Statistical analysis was done in SPSS. Results: Half of subjects were exposed to phthalates. MEP induced an increase in FT4 in obese participants and had no influence on FT3. TSH was increased in obese MEP positive female subjects. MEHP induced a decrease in FT4 in lean participants and a decrease of FT3 in lean males. There was no correlation between MEHP and TSH. Influence of MEP/MEHP on leptin secretion. A tendency for negative correlation between leptin and FT4 was seen. There was no influence of leptin on FT3 and TSH. Conclusion: Our population is greatly exposed to phthalates. MEP and MEHP influence certain thyroid indicators i.e. cause thyroid disruption. Phthalates do not influence leptin secretion in our study. There is a mild effect of leptin on FT4.
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32

Potratz, Sarah [Verfasser]. "In vitro Untersuchungen zellulärer Effekte nach Exposition mit polyzyklischen aromatischen Kohlenwasserstoffen und endokrinen Disruptoren mittels Metabolomanalysen : Identifizierung von Biomarkern für die Risikobewertung und Einblick in toxikologisch relevante Stoffwechselwege in HaCaT und MCF-7 Zellen / Sarah Potratz". Berlin : Freie Universität Berlin, 2017. http://d-nb.info/1139255118/34.

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Merker, Philine [Verfasser], Wolfgang [Akademischer Betreuer] Wuttke, Michael [Akademischer Betreuer] Hüfner y Martin [Akademischer Betreuer] Oppermann. "Wie gefährdet sind wir durch endokrine Disruptoren? : Effekt von Daidzein und 4-MBC im Vergleich mit 17β-Östradiol auf den Uterus der ovarektomierten Ratte / Philine Merker. Gutachter: Wolfgang Wuttke ; Michael Hüfner ; Martin Oppermann. Betreuer: Wolfgang Wuttke". Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2013. http://d-nb.info/1044736437/34.

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Giffing, Antje [Verfasser]. "Untersuchung der Effekte der Modellsubstanz Methimazol als Endokriner Disruptor der Schilddrüsenfunktion am Zebrafisch (Danio rerio) / Antje Giffing". 2007. http://d-nb.info/985143916/34.

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Hilgendorf, Leonie. "Östrogenes Potential des endokrinen Disruptors 4-MBC im Reproduktionstrakt von ovariektomierten Ratten". Doctoral thesis, 2011. http://hdl.handle.net/11858/00-1735-0000-0006-B1DD-0.

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Klammer, 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.

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Linhartová, Zuzana. "Funkční analýza kvality spermií po působení vybraných endokrinních disruptorů". Master's thesis, 2011. http://www.nusl.cz/ntk/nusl-296426.

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The aim The aim of my study was to determine whether the selected endocrine disruptors (EDs) affect reproductive parameters of sperm. Due to two experimental models, in which was tested the influence of selected Eds, my work is divided into two parts: A) On the boar model (Sus scrofa) was tested effect of selected EDs (zearalenone (ZEN), di(2-ethylhexyl) phthalate (DEHP), vinclozolin (VIN) on the course of capacitation, acrosome responses in vitro and changes in the detection and localization of selected proteins. B) On the fish model (Perca fluviatilis L.) was tested the influence of the selected ED- bisphenol A (BPA) on the motility and velocity of fish sperm movement. Results Mammalian model In mammalian model the course of capacitation and acrosome reaction was significantly influencing by the examined EDs in comparision with control samples. The increase of the number of marked cells during capacitation and reduce of the number of marked cells after AR compared with the differences between experimental and control samples was confirmed by the flow cytometry method. At higher concentrations EDs clearly inhibited acrosome response and thus reduce the number of sperm capable of fertilization. The relevancy of the results of detection acrosome reaction was confirmed by using various methodological...
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Klinker, Friederike E. "Die Effekte von endokrinen Disruptoren auf den Herzmuskel orchidektomierter Ratten". Doctoral thesis, 2014. http://hdl.handle.net/11858/00-1735-0000-0022-5E9D-F.

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ZIEL Die Auswirkungen von Endokrinen Disruptoren (ED) auf die Reproduktionsorgane sind umfangreich untersucht, da eine Vielzahl endokrin wirksamer Substanzen östrogene und antiandrogene Wirkungen haben. Da sowohl Östrogen- als auch Androgenrezeptoren auch am Herzen nachgewiesen werden konnten, wurde in der vorliegenden Arbeit der Frage nachgegangen, ob ED auch direkte Wirkungen auf den Herzmuskel haben. METHODEN Die Untersuchungen erfolgten am Rattenmodell. Als Kontrollgruppe dienten orchidektomierte männliche Ratten. Getestet wurden folgende Substanzen, die den Tieren über das Futter zugesetzt wurden: Die Phytoöstrogene Genistein (Gen), Resveratrol (Res) und 8-Prenylnaringenin (8-PN), die UV-Filter-Substanzen Benzophenon-2 (BP-2), 4-Methylbenzyliden-Camphor (4-MBC) und Octylmethoxycinnamat (OMC), denen eine östrogene Wirkung zugeschrieben wird, sowie die die Steroidhormone Östradiol (E2) und Testposteron (T). Weiterhin wurden die Pestizide Linuron (Lin) und Procymidon (Pro) untersucht, die dagegen antiandrogene Wirkung haben und deshalb an intakten Tieren getestet wurden. Untersucht wurden einerseits die Herzmuskelfaserfläche mittels histomorphometrischer Auswertung, andererseits die Anzahl der proliferierenden Zellen mittels immunzytologischer Färbung mit Proliferating Cell Nuclear Antigen (PCNA). ERGEBNISSE Die Orchidektomie führte zu einer signifikanten Verkleinerung der Herzmuskelfaserfläche sowie einer Erhöhung der proliferierenden Zellen. Unter den östrogen wirksamen Substanzen führten - bis auf 4-MBC und OMC - alle Testsubstanzen sowie die E2 und T zu einer signifikanten Vergrößerung der Herzmuskelfaserfläche , wobei Res den stärksten Effekt hatte. Alle Testsubstanzen außer 8-PN erzeugten außerdem eine Verringerung der proliferierenden Zellen. Hier zeigte sich der kleinste Anteil an proliferierenden Zellen bei 4-MBC. Bei den Substanzen mit bekannter antiandrogener Wirkung, Lin und Pro, bewirkte lediglich Lin eine signifikante Vergrößerung der Herzmuskelfaserfläche. Auch der Anteil an proliferierenden Zellen wurde durch die Gabe von Lin und Pro kaum beeinflusst. SCHLUSSFOLGERUNG Alle untersuchten Endokrinen Disruptoren hatten Auswirkungen auf das Herz. Einige Wirkungen der Substanzen mit bekannter östrogener Wirkung entsprechen nicht denen von E2, weshalb hier von anderen, Östrogenrezeptor-unabhängigen Wirkmechanismen ausgegangen werden muss. Die beiden antiandrogenen Substanzen Lin und Pro zeigten keine wesentliche Wirkung auf den Herzmuskel der intakten Tiere. Zur Klärung der Frage, ob die Veränderungen am Herzmuskel gesundheitsschädlich für den Menschen sind, sind weitere Untersuchungen nötig.
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39

Litvinov, Vitali. "Wirkungen endokriner Disruptoren auf Prostata und Samenblase der Sprague-Dawley-Ratte". Doctoral thesis, 2012. http://hdl.handle.net/11858/00-1735-0000-0006-B2E7-1.

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40

Otáhalová, Barbora. "Inhibice enzymové aktivity cytochromů P450 endokrinním disruptorem 17α-ethinylestradiolem". Master's thesis, 2020. http://www.nusl.cz/ntk/nusl-434099.

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17α-ethinylestradiol (EE2) is a synthetic hormone, derivative of the natural hormone estradiol. EE2 is one of the the most prescribed drugs in the world. It belongs to the estrogenic endocrine disrupter chemicals. These compounds are able to alter functions of the endocrine system and cause adverse effects in the organism, offspring and (sub)population. In this thesis, there are observed effects of 17α-ethinylestradiol on enzyme activities of main enzymes involved in phase I of xenobiotic biotransformation, i.e. cytochromes P450 (CYP), in vitro. Isoforms of CYP subfamilies 1A, 2B, 2C, 2E and 3A were studied in rats and humans. Each CYP isoform was incubated with EE2 at two concentrations, 10μM EE2 and the concentration corresponding to the substrate concentration in the specific marker reactions of individual CYP isoforms. The results indicate, that in rat liver microsomes the activity of all studied isoforms except CYP1A2 was decreased in the presence of EE2. When EE2 was added to the incubation mixture at the concentration of the reaction substrate, the greatest decrease in enzyme activity was observed for CYP2C6, with the remaining activity only 36%. In human liver microsomes, the activity of CYP2B6, CYP2C9, CYP2E1 and CYP3A4 was also effected by EE2. As in the case of rat model, CYP2C subfamily...
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41

Ezechiáš, Martin. "Nové zpomalovače hoření v životním prostředí". Master's thesis, 2011. http://www.nusl.cz/ntk/nusl-312233.

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In the recent years, many research articles focused on endocrine disrupting compounds in the environment. Some of these compounds are listed in a group named brominated flame retardants. However, only few articles investigated endocrine activity of several "new" brominated flame retardants. These chemicals such as 1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE) or bis(2-ethylhexyl) tetrabromophthalate (TBPH) are newly used due to ban of some previously most produced brominated flame retardant mixes. In this study, we used two recombinant yeast screens to measure estrogenic, androgenic, antiestrognic and antiandrogenic activities of some alternative brominated flame retardants. We also used ligninolytic fungi to investigate biodegradation of these compounds. Our results suggest, that 2,4,6-tribromophenol (TBP) may be a new environmental endocrine disruptor. This substance showed antiestrogenic and antiandrogenic activity in our tests. 1,2-bis(2,4,6- tribromophenoxy)ethane (BTBPE) had certain antagonistic activity too. In the biodegradation experiment, only three compounds showed significant degradation during the test period. No biodegradation have been observed for other compounds. In this study, we applied gas chromatography with mass spectrometry to analyze these "new" flame retardants. Method for gas...
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42

Vossmann, Vera. "Wirkung von Endokrinen Disruptoren auf die Tibiametaphyse der ovarektomierten Sprague Dawley Ratte". Doctoral thesis, 2011. http://hdl.handle.net/11858/00-1735-0000-0006-B259-1.

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43

Čermáková, Tereza. "Hormonální aktivita v odpadních vodách". Master's thesis, 2018. http://www.nusl.cz/ntk/nusl-380276.

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Endocrine disruptors are natural or manmade substances which affect hormonal systems of organisms. Biologically relevant concentrations are commonly being detected in the environment. The effluents of wastewater treatment plant present their significant secondary source. Due to their occurence and quantity the interest in mixtures increases. Ecotoxicological assays with genetically modified Saccharomyces cerevisiae were aplied to verify reliability of predictive mathematical models for mixtures of standards (estrone, 17β-estradiol, 17α-ethinylestradiol, estriol, bisphenol A, irgasan, 4-nonylphenol). Chromatographic analysis along with yeast assays were used for the evaluation of real samples of wastewater treatment plant effluents and sediments. Schindler's predictive model and Full logistic model (FLM) were more reliable for predicting the whole dose-response curve compared to Generalized concentration addition (GCA). Predicted values of a parameter EC50 from all three models were comparable to empirical measurements. Three out of four samples exhibited estrogenic activity 0.65 - 1.70 ng/L 17β-estradiol ekvivalent (EEQ) above the limit of detection 0.13 - 0.33 ng/L EEQ. Antiestrogenic activity was detected in one of the samples. Prediction could be carried out only in the case of the sediments...
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44

Langová, Jana. "Stanovení zástupců endokrinních disruptorů ve vzorcích odpadních vod v ČR". Master's thesis, 2013. http://www.nusl.cz/ntk/nusl-322735.

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Endocrine disruptors represent a group of chemical compounds that are able to negatively influence the hormonal system of vertebrates. Environmental Protection Agency (U.S.EPA) defines these compounds as exogenous substance or mixture that interferes with the synthesis, secretion, transport, binding, activity, or degradation of natural hormones. This can be observed at the level of the individual organism, its progeny, populations and subpopulations. All these changes have negative effects on homeostasis, reproduction, development or change the behavior of the affected animals. This work focuses on 7 endocrine disruptors - natural estron, 17β estradiol, estriol, and synthetic 17α-ethynylestradiol, irgasan (triclosan), 4-nonylfenol, bisphenol A in the influent and effluent of wastewater plants in the Czech Republic. The thesis contains an optimization of endocrine disruptors determination in wastewater, a preliminary screening to determinate concentration levels, 24 hours composite samples and monitoring of one selected wastewater plant during a day. The analytical procedure is based on filtration, solid-phase extraction (SPE), gel permeation chromatography (GPC), derivatization and gas chromatography coupled with mass spectrometry (GC/MS). Keywords: endocrine disruptors, wastewaters, Czech...
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45

Müller, Matthias. "Der Einfluss endokriner Disruptoren auf das Fettgewebe der Sprague-Dawley-Ratte". Doctoral thesis, 2007. http://hdl.handle.net/11858/00-1735-0000-0006-AF3B-B.

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46

Dvořáková, Eva. "Vliv zearalenonu na reprodukční parametry a expresi vybraných genů u myší". Master's thesis, 2012. http://www.nusl.cz/ntk/nusl-306656.

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A number of chemicals may have a negative impact on the environment and wildlife. Endocrine disruptors (EDs), which can mimic estrogen, interfere with natural hormones in organism and can have a negative effect on the reproductive system. Such substances include zearalenone (ZEA) - mycotoxin, produced by the fungi Fusarium. Despite the non-steriodal structure of its molecule, ZEA and its derivates possess potent estrogenic activity. The influence of ZEA on reproductive parameters and changes in expression of selected genes were tested in the outbred line of mice. This study showed significant effects of ZEA on number of reproductive performances. This effect was observed at lower examined dose, to which are humans normally exposed, and at higher doses, both showed changes in the tested parameters.
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47

Opitz, Carl Christian. "Auswirkungen von Östradiol, Bisphenol A und Octylmethoxycinnamat in östrogen-sensitiven Organen im Langzeitversuch an ovarektomierten Mäusen". Doctoral thesis, 2012. http://hdl.handle.net/11858/00-1735-0000-000D-EFDC-4.

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48

Kausch, Ulf [Verfasser]. "Auswirkung verschiedener oestrogen wirksamer endokriner Disruptoren auf die Genexpression des Zebrabärblings (Danio rerio) / Ulf Kausch". 2006. http://d-nb.info/985435402/34.

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Müller, Matthias [Verfasser]. "Der Einfluss endokriner Disruptoren auf das Fettgewebe der Sprague-Dawley-Ratte / vorgelegt von Matthias Müller". 2007. http://d-nb.info/991514386/34.

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50

Holecová, Jana. "Vliv vybraných endokrinních disruptorů na cytochromy P450 1B1 a 3A1/2". Master's thesis, 2017. http://www.nusl.cz/ntk/nusl-365115.

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Many exogenous and endogenous compounds are referred to as endocrine disruptors (EDCs), as they interfere with natural synthesis, signaling and metabolism of endogenous hormones. Common exogenous endocrine disruptors are benzo(a)pyrene (BaP) and 17α-ethinylestradiol (EE2). Endogenous endocrine disruptor 17β-estradiol (E2) is frequently present in the environment as well. In this thesis, the effect of the mentioned EDCs and their combinations on gene and protein expression of CYP1B1, 3A1 and 3A2 in rat liver, kidney and lung was determined. Protein expression was studied using Western blot method and specific antibodies; gene expression was assessed by quantitative PCR. Moreover, the effect of tested EDCs and their combinations on BaP metabolism and CYP3A specific activity (measured as testosterone 6β-hydroxylation) were studied in liver microsomal samples. It was confirmed, that BaP significantly increases CYP1B1 expression in rat liver and lung both alone and together with EE2 or E2. Pretreatment of rat with E2 and BaP increases the ability of BaP to induce CYP1B1 expression. On the contrary, EE2, E2 and their combination decrease the CYP1B1gene expression. The rate of BaP metabolites formed in liver microsomal samples increases in rats pretreated with BaP and its combinations. In liver, there was...
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