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Hazardous Waste Site Proximity and Type 2 Diabetes: From Youths to AdultsJohnson, Theresa Ann 01 January 2019 (has links)
Type 2 diabetes has reached epidemic proportions in adults and youths. Persistent organic pollutants and endocrine-disrupting chemicals (EDCs), such as pesticides, dioxins, and organochlorines, are omnipresent and persist in the environment with potential for human exposure via contaminated air, waterways, soil, and human food supply. EDCs have been correlated with diabetes incidence and risks. Residential proximity to hazardous waste sites (HWS) has been correlated with increased hospital admission rates for diabetes. The study used a sample population (N = 1,724), ages ≥ 12 years from the 2005-2012 Continuous NHANES and HWS data from the National Priorities List of Superfund Sites. The ecosocial theory of disease distribution, and geocoordinates provided theoretical support. Mann-Whitney U test and binary logistic regression analysis were used to investigate the relationship between residence ≤ 1 mile compared with residence >1 mile from a HWS in NHANES surveyed counties of NJ, PA, NY, and CA on the outcome abnormal A1c ≥ 5.7% while controlling the effect of the moderators: abnormal body mass index (BMI), age, sex, and race/ethnicity on the relationship. Participants with a BMI ≥ 28.95 kg/m2 were 1.8 times and persons ≥ 58 years of age were 2.1 times more likely to have an A1c ≥ 5.7%. Also, non-Hispanic Whites residing >1 mile of a HWS had 82.1 % reduced risk of abnormal A1c compared with the same group residing ≤ 1 mile of a HWS. The results forge opportunities for future studies to consider border distance between residence and HWS. In addition, the results may promote positive social change through diabetes risks education, environmental health education, and practices and raise dialogue about social justice and the geographic distribution of hazardous waste sites.
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Caractérisation des effets métaboliques d’un mélange de polluants à faibles doses dans un modèle de souris déficientes en oestrogènes / Characterization of the metabolic effects of a low-dose mixture of pollutants in a mouse model of estrogen-deficiencyJulien, Benoit 09 July 2019 (has links)
La ménopause est un facteur de risques associé au développement des maladies métaboliques. Du fait de ce déficit hormonal, les femmes ménopausées pourraient présenter des risques particuliers une fois exposées à des agents chimiques capables de perturber le système endocrinien. Pour en savoir plus, nous avons mis au point un modèle de souris ovariectomisées supplémentées ou non en œstradiol (E2), et exposées de manière chronique à un mélange de polluants (TCDD, PCB153, DEHP et BPA) ajoutés à une alimentation obésogène. Chaque polluant est utilisé à une dose équivalente à la Dose Journalière Tolérable, et l’exposition recouvre différents stades de développement, incluant ou non la période maternelle (gestation + lactation). Nos résultats indiquent qu’en condition d’obésité induite par le régime, l’ovariectomie accentue la prise de poids, l’intolérance au glucose et l’insulino-résistance chez les souris femelles adultes. Ce phénotype est associé à une diminution de la signalisation œstrogénique dans le foie et une dérégulation de l’adipogenèse et de l’inflammation dans le tissu adipeux. De manière intéressante, le mélange de polluants réduit l’impact délétère de l’ovariectomie sur le phénotype métabolique, possiblement par une amélioration de la signalisation œstrogénique dans le foie et le tissu adipeux. Nos résultats suggèrent fortement que ces effets dépendent d’une exposition maternelle. En conclusion, nous montrons que notre mélange de polluants possède une activité œstrogéno-mimétique. Ceci pourrait avoir une implication dans la compréhension du rôle des polluants environnementaux dans le développement des maladies métaboliques chez la femme en transition ménopausique / Menopause is a risk factor associated with the development of metabolic diseases. Because of estrogen deficiency, postmenopausal women may be at particular risk when exposed to chemical agents that can disrupt the endocrine system. To get more insight, we have developed a model of ovariectomized mice supplemented or not with estradiol (E2), and chronically exposed to a mixture of pollutants (TCDD, PCB153, DEHP and BPA) added to an obesogenic diet. Each pollutant was used at a dose close to the Tolerable Daily Intake dose, and the exposure had covered different stages of development, including or not the maternal period (gestation + lactation). Our results indicate that in diet-induced obesity, ovariectomy triggered weight gain, increase glucose intolerance and insulin resistance. This phenotype was associated with decreased estrogenic signaling in liver and deregulation of adipogenesis and inflammation in adipose tissues. Interestingly, the mixture of pollutants reduced the deleterious impact of ovariectomy on the metabolic phenotype, possibly through an alleviation of estrogenic signaling in both liver and adipose tissues. These data were not reproduced in mice not exposed to pollutants during the maternal life. In conclusion, the mixture of pollutants displayed some estrogeno-mimetic activity. This could have implications in understanding the role of environmental pollutants in the development of metabolic diseases in women in menopausal transition.
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Electrolytic determination of phthalates organic pollutants with n nostructured titanium and iron oxides sensorsMatinise, Nolubabalo. January 2010 (has links)
<p>This work reports the chemical synthesis, characterisation and electrochemical application of titanium dioxide (TiO2) and iron oxide (Fe2O3) nanoparticles in the determination of phthalates. The other part of this work involved electrochemical polymerization of aniline doped with titanium and iron oxide nanoparticles for the sensor platform in the electrolytic determination of phthalates. The TiO2 and Fe2O3 nanoparticles were prepared by sol gel and hydrothermal methods respectively. Particle sizes of 20 nm (TiO2) and 50 nm (Fe2O3) were estimated from transmission electron microscopy (TEM) The other technical methods used in this study for the characterization of the TiO2 and iron oxide Fe2O3 NPs were SEM, XRD and UV- visible spectroscopy. Cyclic voltammetry, square wave voltammetry and electrochemical impedance spectroscopy (EIS) were used to study the electrochemical properties of the nanoparticles. These electrochemical studies of the nanoparticles were performed with a Fe2O3 or TiO2/nafion/glassy carbon membrane electrode in 0.1 M phosphate buffer (pH 7.0) and 0.1 M lithium perchlorate (pH 6.8) under an aerobic condition.</p>
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Vergleichende In-Vivo- und In-Vitro-Untersuchungen zur Bestimmung der CYP1A1-Aktivitätsveränderung durch hormonell aktive Stoffe / Comparative in vivo and in vitro studies to determine the CYP1A1 activity modulation through hormonal active substancesVeelken, Karen 02 June 2015 (has links)
No description available.
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Wirkung von Endokrinen Disruptoren auf die Tibiametaphyse der ovarektomierten Sprague Dawley Ratte / The effect of endocrine disruptors on the tibial methaphysis of ovariectomized Sprague-Dawley-ratsVossmann, Vera 08 November 2011 (has links)
No description available.
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Wirkungen endokriner Disruptoren auf Prostata und Samenblase der Sprague-Dawley-Ratte / Effects of endocrine disruptors on prostate and seminal vesicle of the Sprague-Dawley-ratLitvinov, Vitali 02 April 2012 (has links)
No description available.
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Electrolytic determination of phthalates organic pollutants with n nostructured titanium and iron oxides sensorsMatinise, Nolubabalo. January 2010 (has links)
<p>This work reports the chemical synthesis, characterisation and electrochemical application of titanium dioxide (TiO2) and iron oxide (Fe2O3) nanoparticles in the determination of phthalates. The other part of this work involved electrochemical polymerization of aniline doped with titanium and iron oxide nanoparticles for the sensor platform in the electrolytic determination of phthalates. The TiO2 and Fe2O3 nanoparticles were prepared by sol gel and hydrothermal methods respectively. Particle sizes of 20 nm (TiO2) and 50 nm (Fe2O3) were estimated from transmission electron microscopy (TEM) The other technical methods used in this study for the characterization of the TiO2 and iron oxide Fe2O3 NPs were SEM, XRD and UV- visible spectroscopy. Cyclic voltammetry, square wave voltammetry and electrochemical impedance spectroscopy (EIS) were used to study the electrochemical properties of the nanoparticles. These electrochemical studies of the nanoparticles were performed with a Fe2O3 or TiO2/nafion/glassy carbon membrane electrode in 0.1 M phosphate buffer (pH 7.0) and 0.1 M lithium perchlorate (pH 6.8) under an aerobic condition.</p>
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Avaliação da presença de metilparabeno e propilparabeno no ambiente aquático e seus potenciais estrogênicos e a toxicidade aguda. / Evaluation of the presence of methylparaben and propylparaben in the aquatic environment and their potential estrogenic and acute toxicity.Carolina Gomes Moreira 14 April 2014 (has links)
Atualmente no cenário mundial a qualidade da água tem gerado muitas
preocupações, pois milhares de produtos sintéticos são produzidos para facilitar
muitas práticas industriais, domésticas e pessoais e com isso diversas substâncias
químicas utilizadas para esses fins são introduzidas no meio ambiente. Os
parabenos são substâncias químicas utilizadas pelas indústrias farmacêuticas, de
alimentos e cosméticos e que cuja função é a conservação, sendo que há muitos
questionamentos em relação a sua segurança, pois alguns relatórios têm mostrado
que a exposição a esses parabenos pode modular ou perturbar o sistema endócrino
e com isso gerar consequências prejudiciais à saúde humana e aos ambientes
aquáticos. Esse estudo teve como objetivo avaliar a presença dos Parabenos
Metilparabeno e Propilparabeno no ambiente aquático e os seus potenciais
estrogênicos e a toxicidade aguda. A metodologia se desenvolveu a partir do ensaio
in vitro YES para a determinação da atividade estrogênica, ensaios de toxicidade
aguda em Daphnia similis e em Aliivibrio fischeri e a quantificação dos parabenos na
água do Rio Maracanã-RJ através da cromatografia líquida acoplada ao
espectrômetro de massa. Os resultados obtidos para a CE50 dos MP e PP, a partir
do ensaio in vitro YES, foi de 18,91 mgL-1 e 7 mgL-1 e a magnitude da resposta foi de
10-5 e 10-4 menos potente que 17ß-estradiol para o MP e o PP, respectivamente. A
partir do ensaio de toxicidade aguda, os valores de CE50 obtidos em Daphnia
similis, foi de 29,42 mgL-1 e 9,94 mgL-1e em Aliivibrio fischeri foi de 3,047 mgL-1 e
1,946 mgL-1, respectivamente, com isso observou-se que o PP é mais tóxicos em
todos os organismos testados, sendo mais tóxicos para um e menos para outros. A
água do Rio Maracanã não foi tóxica para a Daphnia similis em nenhum dos dois
pontos, já para o Aliivibrio fischeri foi tóxica em apenas um ponto. As concentrações
encontradas de MP e PP foram maiores no ponto onde, de acordo com os
parâmetros físico-químicos, a qualidade da água não está dentro dos padrões
exigidos pela legislação, sendo quantificados na ordem de ngL-1, contudo é válido
ressaltar que os DEs não são encontrados no meio ambiente separados, eles
interagem entre si e provocam efeitos aditivos ou sinérgicos, sendo muito difícil de
prever qual o efeito, por isso é importante o conhecimento do potencial estrogênico
das substâncias simples, pois em um estudo com uma matriz ambiental, pode-se
observar se houve algum efeito aditivo ou sinérgico de outras substâncias. / Currently on the world stage water quality has generated many concerns,
because thousands of synthetic products are produced to facilitate many industrial,
domestic and personal practices and thereby various chemicals used for these
purposes are introduced into the environment. Parabens are chemicals used by the
pharmaceutical, food and cosmetic and whose function is to conserve, and there are
many questions regarding its safety , as some reports have shown that exposure to
these parabens can modulate or disrupt endocrine system and thereby generate
harmful consequences for human health and aquatic environments . The aim of this
study was to evaluate the presence of Methylparaben and Propylparaben in the
aquatic environment and their potential estrogenic and acute toxicity. The
methodology developed from the in vitro YES assay for the determination of
estrogenic activity, acute toxicity tests with Daphnia similis and Aliivibrio fischeri and
quantification of parabens in water of Maracanã River RJ by liquid chromatography
coupled with mass spectrometry. The EC50 results for the PP and MP, from the in
vitro YES, was 18,91 mgL -1 and 7 mgL-1 and the magnitude of response was less
potent 10-5 and 10-4 that 17ß - estradiol for MP and PP , respectively. From the acute
toxicity test, the EC50 values obtained in Daphnia similis was 29,42 mgL-1 and 9,94
mgL-1, and Aliivibrio fischeri was 3,047 mgL-1 and 1,946 mgL-1, respectively, with it
was observed that PP is more toxic in all organisms tested, and more toxic to one
and less to others . The water of the Maracanã River was not toxic to Daphnia similis
in either points, since for Aliivibrio fischeri was toxic at only one point. Found
concentrations of MP and PP were higher at the point where, according to the
physico-chemical parameters, water quality is not within the standards required by
legislation and quantified in order ngL-1, however its worth to note that the DEs are
not found in the middle separate environment, they interact with each other and
cause additive or synergistic effects , its very difficult to predict what effect , so its
important to know the estrogenic potential of simple substances , since in a study
with an environmental matrix, one can observe if there were any additive or
synergistic effect of other substances .
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Caractérisation de protéines bovines potentiellement impliquées dans la reproduction : GPA2, GPB5, PDI, PEBP et Ubiquitine / Characterization of bovine proteins potentially involved in reproduction : GPA2, GPB5, PDI, PEBP et UbiquitinHaj Hassan, Maya 13 December 2011 (has links)
Nous avons caractérisé cinq protéines bovines qui sont potentiellement impliquées dans la reproduction.Un travail de clonage a été initié qui permettra à terme de purifier les GPA2 et GPB5 recombinantes puis naturelles pour étudier leurs structures. GPA2 et GPB5 sont considérés comme les ancêtres moléculaires des sous-unités α et β des hormones glycoprotéiques. Nous avons montré la relative fragilité thermique de la structure quaternaire de la FSH bovine par rapport aux FSH ovine et humaine et nous avons étudié les propriétés enzymatiques de la PDI (Protein Disulfide Isomerase) en préalable à l’étude de l’activité PDI de GPA2/GPB5. Nous avons aussi purifié la phosphatidyl-ethanolamine-binding protein (PEBP) et l’ubiquitine testiculaires par chromatographie hydrophobe à très haute concentration de sulfate d’ammonium. A partir de la PEBP purifiée, on a produit des anticorps spécifiques chez le lapin qui nous ont permis d’être les premiers à développer un dosage ELISA fiable pour cette protéine. / We characterized five bovine proteins that are potentially involved in reproduction. We started with the cloning of gpa2 and gpb5 cDNAs in order to eventually purify recombinant and natural GPA2 and GPB5 to study their possible quaternary structure. GPA2 and GPB5 are the evolutionary ancestors of Glycoprotein hormones α and β subunits respectively. Meanwhile, we have shown the relative quaternary structure fragility of bovine FSH compared to human and sheep FSH. We also studied the effect of endocrine disruptors on PDI (Protein Disulfide Isomerase) before addressing GPA2/GPB5 PDI activity of GPA2/GPB5 once purified.We succeeded to purify the phosphatidyl-ethanolamine-binding protein (PEBP) and ubiquitin from bovine testis by hydrophobic interaction chromatography at very high ammonium sulfate concentration and we produced specific antibodies (anti-PEBP) in rabbits that allowed us to be the first to develop a reliable Elisa assay for this protein.
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Electrolytic determination of phthalates organic pollutants with n nostructured titanium and iron oxides sensorsMatinise, Nolubabalo January 2010 (has links)
Magister Scientiae - MSc / This work reports the chemical synthesis, characterisation and electrochemical application of titanium dioxide (TiO2) and iron oxide (Fe2O3) nanoparticles in the determination of phthalates. The other part of this work involved electrochemical polymerization of aniline doped with titanium and iron oxide nanoparticles for the sensor platform in the electrolytic determination of phthalates. The TiO2 and Fe2O3 nanoparticles were prepared by sol gel and hydrothermal methods respectively. Particle sizes of 20 nm (TiO2) and 50 nm (Fe2O3) were estimated from transmission electron microscopy (TEM) The other technical methods used in this study for the characterization of the TiO2 and iron oxide Fe2O3 NPs were SEM, XRD and UV- visible spectroscopy. Cyclic voltammetry, square wave voltammetry and electrochemical impedance spectroscopy (EIS) were used to study the electrochemical properties of the nanoparticles. These electrochemical studies of the nanoparticles were performed with a Fe2O3 or TiO2/nafion/glassy carbon membrane electrode in 0.1 M phosphate buffer (pH 7.0) and 0.1 M lithium perchlorate (pH 6.8) under an aerobic condition. / South Africa
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