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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Rapid social regulation of 3β-HSD activity in the songbird brain

Pradhan, Devaleena S. 11 1900 (has links)
Rapid increases in plasma androgens are generally associated with short-term aggressive challenges in many breeding vertebrates. However, some animals such as song sparrows (Melospiza melodia) are aggressive year-round, even during the non-breeding season, when gonads are regressed and systemic testosterone (T) levels are non-detectable. In contrast, levels of the prohormone dehydroepiandrosterone (DHEA) are elevated year-round in the plasma and brain. The local conversion of brain DHEA to potent androgens may be critical in regulating non-breeding aggression. 3β-hydroxysteroid dehydrogenase/Δ4-Δ5 isomerase (3β-HSD) catalyzes DHEA conversion to androstenedione (AE) and the cofactor NAD⁺ assists in this transformation. In this thesis, I asked whether brain 3β-HSD activity is regulated by social encounters in seasonally breeding male songbirds. In Experiment 1, I looked at the long-term seasonal regulation of brain 3β-HSD activity. 3β-HSD activity was highest in the non-breeding season compared to the breeding season and molt. In Experiment 2, I hypothesized that brain 3β-HSD activity is rapidly regulated by short-term social encounters during the non-breeding season. A 30 min social challenge increased aggressive behavior. Without exogenous NAD⁺, there was ~355% increase in 3β-HSD activity in the caudal telencephalon and ~615% increase in the medial central telencephalon compared to controls (p<0.05). With exogenous NAD⁺, there was no effect of social challenge on 3β-HSD activity. These data suggest that endogenous cofactors play a critical role in the neuroendocrine response to social challenges. The increase in brain DHEA conversion to AE during social challenges may be a mechanism to rapidly increase local androgens in the non-breeding season, when there are many costs of systemic T. / Science, Faculty of / Zoology, Department of / Graduate
22

The Effects of Estrogen on the Growth and Tuberization of Potato Plants (Solanum tuberosum cv. 'Iwa') Grown in Liquid Tissue Culture Media

Brown, Greta Suzanne January 2006 (has links)
Mammalian estrogens and estrogen-like compounds known as xeno-estrogens are being found in and excreted into the environment in ever increasing amounts. The xeno-estrogen DDE has been found at high concentrations of 1-5 mg/kg of soil (Aislabie et. al, 1997). These estrogens and xeno-estrogens are having a devastating effect on animal-life, yet little is known or understood on the effects of estrogens on plant-life. Thus it is important to determine what effects (if any) estrogens may have on plants. Other research has shown that estrogen has an effect on plants grown in vitro (Janeczko and Skoczowski, 2005). This research aims to help increase the amount of information on what effects estrogens may have on plants. In this study, the effects of mammalian estrogens (17-β-estradiol, estrone and estriol) on the growth and tuberization of potato plants (Solanum tuberosum L. cv 'Iwa') grown in liquid tissue culture medium are presented. It was found that at even 0.1 mg/L of estrogen, root growth of the plants was diminished and at 10 mg/L of estrogen, plant deformity was apparent and callus growth induced. Acid phosphatase activity of the plants was increased with the addition of 0.1 mg/L and 1 mg/L of estrogen but then decreased with the addition of 10 mg/L of estrogen. Tuber production was slightly reduced in plants treated with estrogen compared to the control.
23

Influência da obesidade e da doença arterial coronária nos níveis séricos de estrona nas mulheres na pós-menopausa / Influence of the obesity and coronary artery disease in blood levels of estrone in postmenopausal women

Silva, Teresa Cristina Barbosa Ferreira da 09 February 2007 (has links)
INTRODUÇÃO: Estudos recentes mostraram maior mortalidade em indivíduos nos extremos dos valores do índice de massa corpórea (IMC). Discute-se, também, a intensidade da influência da obesidade na mortalidade por doenças cardiovasculares (DCV), em mulheres na pós-menopausa, e da participação dos estrógenos endógenos. Neste trabalho, analisamos, prospectivamente, a influência da obesidade e os níveis séricos de estrona nos principais fatores de risco em mulheres na pós-menopausa com doença arterial coronária (DAC), ou de alto risco para DAC, matriculadas no Instituto do Coração do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. MÉTODOS: Estudo prospectivo, realizado entre março de 2004 e setembro de 2006, em 251 mulheres na pós-menopausa com alto risco para eventos cardiovasculares, na ausência de reposição hormonal. Foram estudadas, em 3 visitas semestrais (V1-basal, V2 e V3), as características clínicas (pressão arterial, índice de massa corpórea, fatores de risco para DCV, medicação utilizada, e ocorrência de eventos neste período) e as laboratoriais [glicemia, perfil lipídico, inflamatórias (análise PCR ultra-sensível), bem como e os níveis de estrógeno endógeno (estrona)]. Foram classificadas, segundo o IMC (kg/m2), em normal (18,5<=IMC<25), sobrepeso (25<=IMC<30) e obesa (>=30), e também os níveis de estrona (= e =pg/mL). Foram realizadas as análises univariada, curvas de Kaplan-Meier para mortalidade, segundo os níveis de estrona, e regressão multivariada de Cox. RESULTADOS: Não houve diferenças entre os grupos com relação à idade (71±8 vs 70±7 vs 69±6 anos; p=0,112). O aumento do IMC associou-se a maior prevalência de hipertensão arterial sistêmica (HAS) (81% vs 96% vs 100%; p<0,01), diabetes melito (38% vs 52% vs 69%; p=0,001), e níveis de estrona (22,3±11 vs 22,4±9,4 vs 28,2±16,4 pg/mL; p=0,002). Menores níveis de HDL (58±15 vs 53±12 vs 50±11 mg/dl; p=0,009) e LDL (123±30 vs 115±38 vs 107±36 mg/dl; p=0,039). Os níveis de PCR permaneceram inalterados (0,38±0,33 vs 0,79±1,81 vs 0,63±0,57 mg/dl; p=0,180) e houve tendência de maiores níveis de triglicérides (143±81 vs 167±80 vs 191±149 mg/dl; p=0,061). Níveis séricos de estrona >=25 pg/mL foram observados nas pacientes com maiores níveis de pressão arterial sistólica (140±18 vs 145±18 mmHg; p=0,031), pressão arterial diastólica (82±10 vs 85±9 mmHg; p=0,003), e maiores níveis de glicemia (123±48 vs 146±67 mg/dl; p=0,003), com menor prevalência de DAC (81% vs 67%; p=0,010). Para o seguimento de 1,99±0,54 anos, observou-se aumento gradativo dos níveis de estrona (V1=25±13, V2=31±14, V3=33±17 pg/mL; p<0,01). A incidência de eventos cardiovasculares, segundo os níveis de estrona =25 pg/mL, foi semelhante nos dois grupos analisados, e aconteceram no tempo médio de seguimento de 0,62±0,46 anos. Ocorreram 14 óbitos, sendo 8 por DCV, e 6 por outras causas. A curva de Kaplan-Meier mostrou uma tendência (p=0,074) de maior mortalidade, conforme os níveis de estrona =pg/mL. A idade [OR=1,08 (IC95%:1,01-1,18); p=0,037], PCR [OR=1,24 (IC95%:1,03-1,50); p=0,024] e HAS [6,22 (IC95%:1,86-20,81); p=0,003] foram as variáveis independentes para mortalidade. Conclusões: Nível sérico de estrona, para valor >=25 pg/mL, associou-se a menor prevalência de DAC, porém, não influenciou na incidência de eventos cardiovasculares, nem na mortalidade. Observou-se uma tendência de maior mortalidade em mulheres com níveis de estrona <=15 pg/mL. Na divisão em normal, sobrepeso e obesa observamos padrão de síndrome metabólica nas pacientes. / INTRODUCTION: Recent studies showed higher mortality in people with extreme values of body mass index (BMI). The obesity\'s influence intensity in mortality associated with cardiovascular diseases (CVD) in postmenopausal women and the participation of the endogenous estrogens are unknown. In this study we analysed the influence of BMI and blood levels of estrone in the main risk factors for postmenopausal women (registered on the Heart Institute, University of São Paulo Medical School) with coronary artery disease (CAD) or with high risk for CVD. METHODS: Prospective study performed between March/2004 and September/2006, in 251 postmenopausal women with high risk for cardiovascular events in the absence of hormonal therapy. They were studied, in 3 biannual visits (V1-baseline, V2 and V3), clinical characteristics (blood pressure, BMI, risk factors for CVD, medication in use and events occurred during this period), laboratories exams [glucose, total cholesterol, HDL-cholesterol, LDL- cholesterol, triglyceride, C-reactive protein and blood levels of endogenous estrogen (estrone)]. They were classified according to the BMI (kg/m2) in normal (18,5<=IMC<25), overweight (25<=IMC<30) and obese (>=30) and blood levels of estrone (= and =pg/mL). Univariate analysis, Kaplan-Meier estimation curves according to the blood levels of estrone and the Cox multivariate regression were done. RESULTS: No differences were seen among the groups regarding age (71±8 vs 70±7 vs 69±6 years; p=0,112). The increase of BMI was associated with higher prevalence of hypertension (81% vs 96% vs 100%; p<0,01), diabetes melito (38% vs 52% vs 69%; p=0,001) and blood levels of estrone (22,3±11 vs 22,4±9,4 vs 28,2±16,4 pg/mL; p=0,002); lower levels of HDL-cholesterol blood (58±15 vs 53±12 vs 50±11 mg/dL; p=0,009) and LDL-cholesterol (123±30 vs 115±38 vs 107±36 mg/dL; p=0,039). The levels of C-reactive protein remained unchanged (0,38±0,33 vs 0,79±1,81 vs 0,63±0,57 mg/dL; p=0,180) and a trend of higher levels of triglycerides (143±81 vs 167±80 vs 191±149 mg/dL; p=0,061). Blood level of estrone >=25 pg/mL was observed in pacientes with higher level of systolic blood pressure (SBP) (140±18 vs 145±18 mmHg; p=0,031), diastolic blood pressure (DBP)(82±10 vs 85±9 mmHg; p=0,003) and higher levels of glucose (123±48 vs 146±67 mg/dL; p=0,003), with lower prevalence of CHD (81% vs 67%; p=0,010). During the follow-up of 1,99±0,54 years was noticed a gradual increase of blood level of estrone (V1=25±13, V2=31±14, V3=33±17 pg/mL; p<0,01). The incidence of cardiovascular events according to the blood levels of estrone =25 pg/mL was similar in the two groups and occurred during the follow-up period of 0,62±0,46 years. Were reported 14 deaths: 8 associated with CVD and 6 related to another causes. The Kaplan-Meier estimation curve showed a trend (p=0,074) of greater mortality for CVD according the blood level of estrone of =15 pg/mL. The age [OR=1,08 (IC95%:1,01-1,18);p=0,037], C-reactive protein [OR=1,24 (IC95%:1,03-1,50);p=0,024] and hypertension [6,22 (IC95%:1,86- 20,81);p=0,003] were independent variables for mortality. CONCLUSIONS: Blood level of estrone for readings of >=25 pg/mL, can be associated with smaller prevalence of CAD, but had no impact in cardiovascular events and mortality. We noticed a trend of greater mortality in women with estrone level lower than 15 pg/mL.
24

The Effects of Estrogen on the Growth and Tuberization of Potato Plants (Solanum tuberosum cv. 'Iwa') Grown in Liquid Tissue Culture Media

Brown, Greta Suzanne January 2006 (has links)
Mammalian estrogens and estrogen-like compounds known as xeno-estrogens are being found in and excreted into the environment in ever increasing amounts. The xeno-estrogen DDE has been found at high concentrations of 1-5 mg/kg of soil (Aislabie et. al, 1997). These estrogens and xeno-estrogens are having a devastating effect on animal-life, yet little is known or understood on the effects of estrogens on plant-life. Thus it is important to determine what effects (if any) estrogens may have on plants. Other research has shown that estrogen has an effect on plants grown in vitro (Janeczko and Skoczowski, 2005). This research aims to help increase the amount of information on what effects estrogens may have on plants. In this study, the effects of mammalian estrogens (17-β-estradiol, estrone and estriol) on the growth and tuberization of potato plants (Solanum tuberosum L. cv 'Iwa') grown in liquid tissue culture medium are presented. It was found that at even 0.1 mg/L of estrogen, root growth of the plants was diminished and at 10 mg/L of estrogen, plant deformity was apparent and callus growth induced. Acid phosphatase activity of the plants was increased with the addition of 0.1 mg/L and 1 mg/L of estrogen but then decreased with the addition of 10 mg/L of estrogen. Tuber production was slightly reduced in plants treated with estrogen compared to the control.
25

Towards rapid electrochemical test system of polyanilino-laccase-on-gold enzyme nanobiosensor for water estrogens

Qakala, Sinazo January 2013 (has links)
>Magister Scientiae - MSc / Current water treatment technologies do not remove many endocrine disruptor compounds (EDCs) such as 17α-ethynylestradiol (EE2) in its entirety, and the amount of these pollutants that continues to enter the aquatic environment through wastewater effluents is still capable of causing harmful health effects. Therefore the development of simpler and more sensitive biosensor system for detection of EE2 must be developed which have high responsiveness, low cost and easy handling. Therefore the aim of this study was to work towards the development of rapid test system of polyaniline-laccase on gold enzyme nanobiosensor (PANI-PSSA/Lac/Glu) for water estrogens. Preliminary studies were first done on the materials used in this study: estrogens, laccase, gold nanoparticles (AuNPs), and electropolymerized PANI-PSSA. Laccase was shown to be active towards EE2 and the enzyme could be stored for over three months. EE2 solution also could be used for over three months. Buffer used in this study was found to be suitable. Phosphoric acid (H3PO4) was a suitable electrolyte than hydrochloric acid (HCl) to be used for the electropolymerization of aniline and was used because it has same ions as the McIlvaine buffer (McIlB) which the post-deposition CVs indicated the formation of electrochemically very stable film. AuNPs were successfully synthesized and its size was identified to be less than 22 nm. McIlB used for testing electrochemical properties of AuNP. CVs of GC/PANI-PSSA and GC/PANIPSSA/ Au showed no difference before and after exposure to aq. EE2 solution, an indication of being re-usable and could also serve as stable immobilising platform in laccase biosensor. When interrogating with electrochemical impedance spectroscopy (EIS), the charge transfer resistance (Rct) of both GC/PANI-PSSA and GC/PANI-PSSA/Lac/Glu showed an average increase by about 2.4% and 21% before and after exposure of EE2, respectively. This shows that the GC/PANI-PSSA/Lac/Glu was a functional EE2 biosensor and showing a positive step towards achieving a re-usable biosensor for EE2 as a model water estrogen. Future work Page | vi will focus on exploring different ways of improving the biosensor’s surface regeneration and its sensitivity to EE2.
26

Efeitos vasculares promovidos pela estrona em ratas Wistar ovariectomizadas / Vascular effects promoted by estrone in ovariectomized Wistar rats

Oliveira, Thiago Sardinha de 31 August 2018 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2018-09-11T10:46:39Z No. of bitstreams: 2 Tese - Thiago Sardinha de Oliveira - 2018.pdf: 4687551 bytes, checksum: 1e4f2d0e9cb8438779749f49756c0b0b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-09-11T11:12:23Z (GMT) No. of bitstreams: 2 Tese - Thiago Sardinha de Oliveira - 2018.pdf: 4687551 bytes, checksum: 1e4f2d0e9cb8438779749f49756c0b0b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-09-11T11:12:24Z (GMT). No. of bitstreams: 2 Tese - Thiago Sardinha de Oliveira - 2018.pdf: 4687551 bytes, checksum: 1e4f2d0e9cb8438779749f49756c0b0b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-08-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Estrone (E1), the major component of Premarin® and predominant estrogen in postmenopausal women, does not have its vascular effects involving its vasodilatory mechanism of action completely elucidated. Therefore, the aim of this study was to evaluate the effects of E1 treatment on the vascular reactivity of isolated aortic rings and blood pressure in ovariectomized Wistar rats (OVX). For this purpose, 12 week-old Wistar rats were divided into four experimental groups, Sham (physiological estrous rats treated with vehicle), OVX (OVX rats treated with vehicle), OVX + E1 (OVX rats treated with 825μg / kg of E1) and OVX + 17β-estradiol (E2) (OVX rats treated with 15μg / kg of E2). The treatments started after the 8 weeks of surgery trough subcutaneous pathway for 30 days. At the end of treatment, blood pressure measurement by tail plethysmograph was performed. In addition, aortic rings were isolated to evaluate contractile response to phenylephrine (Phe), relaxation to acetylcholine (ACh) or sodium nitroprusside (NPS) by means of concentration curves. The response to ACh in rings previously incubated with superoxide dismutase (SOD), catalase (CAT) or apocynin (NADPH oxidase inhibitor) was also evaluated. The protein expression of SOD, CAT, NOX 1, NOX 2 and NOX 4 were quantified by Western blotting. Follow-up of the weight gain after the OVX or Sham procedure was also performed. After euthanasia, the weight of retroperitoneal fat, uterus and heart were evaluated. E1 treatment decreased body weight and retroperitoneal fat, increased uterine weight, and corrected both the increased blood pressure, and the decreased hyperreactivity to Phe vasoconstrictor agent and also increased endothelium-dependent vasodilatory response to ACh. The effects presented by this hormone are related to compensatory mechanisms in the activity of antioxidant enzymes such as SOD and catalase besides the reduction in the expression of the NADPH oxidase NOX 4 isoform. In addition, E1 reverses the increase in total and LDL cholesterol in the OVX group. Our study confirms the role of oxidative stress in endothelial dysfunction of OVX rats and further demonstrates that E1 reverses elevation of blood pressure and restores endothelial function in OVX rats. / A estrona (E1), componente majoritário do Premarin® e estrogênio predominante na circulação feminina na pós-menopausa, não possui seus efeitos vasculares e mecanismos de ação completamente elucidados. Diante disso, o objetivo do presente trabalho foi avaliar os efeitos do tratamento com E1 em ratas Wistar ovariectomizadas (OVX) sobre a reatividade de anéis de aorta e pressão arterial. Para este estudo, ratas com 12 semanas de idade foram divididas em quatro grupos experimentais, Sham (ratas em estro fisiológico tratadas com veículo), OVX (ratas OVX tratadas com veículo), OVX + E1 (ratas OVX tratadas com 825μg/Kg de E1) e OVX + 17β-estradiol (E2) (ratas OVX tratadas com 15μg/Kg de E2). Os tratamentos foram iniciados após 8 semanas da cirurgia pela via subcutânea pelo período de 30 dias. Ao final do tratamento, foi realizada a medida de pressão arterial por pletismografia de cauda.Além disso, anéis de aorta foram isolados para avaliar resposta contrátil à fenilefrina (Phe), relaxamento à acetilcolina (ACh) ou ao nitroprussiato de sódio (NPS) por meio de curvas de concentração efeito cumulativas. Foi ainda avaliada a resposta à ACh em anéis incubados previamente com superóxido dismutase (SOD), catalase (CAT) ou apocinina (inibidor da NADPH-oxidase (NOX)). A expressão protéica da SOD, CAT, NOX 1, NOX 2 e NOX 4 foi quantificada por Western-blot. Foi realizado o acompanhamento do ganho de peso após o procedimento de ovariectomia nos grupos OVX ou Sham e, após a eutanásia, foi avaliado o peso da gordura retroperitoneal, útero e coração. O tratamento com E1 diminuiu o peso corporal e a gordura retroperitoneal, aumentou o peso uterino, normalizou os níveis de pressão arterial, o aumento da resposta contrátil à Phe e a resposta vasodilatadora dependente de endotélio à ACh. Os efeitos apresentados por este hormônio estão relacionados com mecanismos compensatórios na expressão e atividade de enzimas antioxidantes como SOD e CAT, além da redução na expressão da isoforma NOX 4. Além disso, a E1 reverteu o aumento do colesterol total e LDL observados nas ratas OVX. Os dados apresentados demonstram o papel benéfico da E1 frente ao estresse oxidativo na disfunção vascular, restabelecendo a função endotelial e os níveis fisiológicos da pressão arterial.
27

Influência da obesidade e da doença arterial coronária nos níveis séricos de estrona nas mulheres na pós-menopausa / Influence of the obesity and coronary artery disease in blood levels of estrone in postmenopausal women

Teresa Cristina Barbosa Ferreira da Silva 09 February 2007 (has links)
INTRODUÇÃO: Estudos recentes mostraram maior mortalidade em indivíduos nos extremos dos valores do índice de massa corpórea (IMC). Discute-se, também, a intensidade da influência da obesidade na mortalidade por doenças cardiovasculares (DCV), em mulheres na pós-menopausa, e da participação dos estrógenos endógenos. Neste trabalho, analisamos, prospectivamente, a influência da obesidade e os níveis séricos de estrona nos principais fatores de risco em mulheres na pós-menopausa com doença arterial coronária (DAC), ou de alto risco para DAC, matriculadas no Instituto do Coração do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. MÉTODOS: Estudo prospectivo, realizado entre março de 2004 e setembro de 2006, em 251 mulheres na pós-menopausa com alto risco para eventos cardiovasculares, na ausência de reposição hormonal. Foram estudadas, em 3 visitas semestrais (V1-basal, V2 e V3), as características clínicas (pressão arterial, índice de massa corpórea, fatores de risco para DCV, medicação utilizada, e ocorrência de eventos neste período) e as laboratoriais [glicemia, perfil lipídico, inflamatórias (análise PCR ultra-sensível), bem como e os níveis de estrógeno endógeno (estrona)]. Foram classificadas, segundo o IMC (kg/m2), em normal (18,5<=IMC<25), sobrepeso (25<=IMC<30) e obesa (>=30), e também os níveis de estrona (= e =pg/mL). Foram realizadas as análises univariada, curvas de Kaplan-Meier para mortalidade, segundo os níveis de estrona, e regressão multivariada de Cox. RESULTADOS: Não houve diferenças entre os grupos com relação à idade (71±8 vs 70±7 vs 69±6 anos; p=0,112). O aumento do IMC associou-se a maior prevalência de hipertensão arterial sistêmica (HAS) (81% vs 96% vs 100%; p<0,01), diabetes melito (38% vs 52% vs 69%; p=0,001), e níveis de estrona (22,3±11 vs 22,4±9,4 vs 28,2±16,4 pg/mL; p=0,002). Menores níveis de HDL (58±15 vs 53±12 vs 50±11 mg/dl; p=0,009) e LDL (123±30 vs 115±38 vs 107±36 mg/dl; p=0,039). Os níveis de PCR permaneceram inalterados (0,38±0,33 vs 0,79±1,81 vs 0,63±0,57 mg/dl; p=0,180) e houve tendência de maiores níveis de triglicérides (143±81 vs 167±80 vs 191±149 mg/dl; p=0,061). Níveis séricos de estrona >=25 pg/mL foram observados nas pacientes com maiores níveis de pressão arterial sistólica (140±18 vs 145±18 mmHg; p=0,031), pressão arterial diastólica (82±10 vs 85±9 mmHg; p=0,003), e maiores níveis de glicemia (123±48 vs 146±67 mg/dl; p=0,003), com menor prevalência de DAC (81% vs 67%; p=0,010). Para o seguimento de 1,99±0,54 anos, observou-se aumento gradativo dos níveis de estrona (V1=25±13, V2=31±14, V3=33±17 pg/mL; p<0,01). A incidência de eventos cardiovasculares, segundo os níveis de estrona =25 pg/mL, foi semelhante nos dois grupos analisados, e aconteceram no tempo médio de seguimento de 0,62±0,46 anos. Ocorreram 14 óbitos, sendo 8 por DCV, e 6 por outras causas. A curva de Kaplan-Meier mostrou uma tendência (p=0,074) de maior mortalidade, conforme os níveis de estrona =pg/mL. A idade [OR=1,08 (IC95%:1,01-1,18); p=0,037], PCR [OR=1,24 (IC95%:1,03-1,50); p=0,024] e HAS [6,22 (IC95%:1,86-20,81); p=0,003] foram as variáveis independentes para mortalidade. Conclusões: Nível sérico de estrona, para valor >=25 pg/mL, associou-se a menor prevalência de DAC, porém, não influenciou na incidência de eventos cardiovasculares, nem na mortalidade. Observou-se uma tendência de maior mortalidade em mulheres com níveis de estrona <=15 pg/mL. Na divisão em normal, sobrepeso e obesa observamos padrão de síndrome metabólica nas pacientes. / INTRODUCTION: Recent studies showed higher mortality in people with extreme values of body mass index (BMI). The obesity\'s influence intensity in mortality associated with cardiovascular diseases (CVD) in postmenopausal women and the participation of the endogenous estrogens are unknown. In this study we analysed the influence of BMI and blood levels of estrone in the main risk factors for postmenopausal women (registered on the Heart Institute, University of São Paulo Medical School) with coronary artery disease (CAD) or with high risk for CVD. METHODS: Prospective study performed between March/2004 and September/2006, in 251 postmenopausal women with high risk for cardiovascular events in the absence of hormonal therapy. They were studied, in 3 biannual visits (V1-baseline, V2 and V3), clinical characteristics (blood pressure, BMI, risk factors for CVD, medication in use and events occurred during this period), laboratories exams [glucose, total cholesterol, HDL-cholesterol, LDL- cholesterol, triglyceride, C-reactive protein and blood levels of endogenous estrogen (estrone)]. They were classified according to the BMI (kg/m2) in normal (18,5<=IMC<25), overweight (25<=IMC<30) and obese (>=30) and blood levels of estrone (= and =pg/mL). Univariate analysis, Kaplan-Meier estimation curves according to the blood levels of estrone and the Cox multivariate regression were done. RESULTS: No differences were seen among the groups regarding age (71±8 vs 70±7 vs 69±6 years; p=0,112). The increase of BMI was associated with higher prevalence of hypertension (81% vs 96% vs 100%; p<0,01), diabetes melito (38% vs 52% vs 69%; p=0,001) and blood levels of estrone (22,3±11 vs 22,4±9,4 vs 28,2±16,4 pg/mL; p=0,002); lower levels of HDL-cholesterol blood (58±15 vs 53±12 vs 50±11 mg/dL; p=0,009) and LDL-cholesterol (123±30 vs 115±38 vs 107±36 mg/dL; p=0,039). The levels of C-reactive protein remained unchanged (0,38±0,33 vs 0,79±1,81 vs 0,63±0,57 mg/dL; p=0,180) and a trend of higher levels of triglycerides (143±81 vs 167±80 vs 191±149 mg/dL; p=0,061). Blood level of estrone >=25 pg/mL was observed in pacientes with higher level of systolic blood pressure (SBP) (140±18 vs 145±18 mmHg; p=0,031), diastolic blood pressure (DBP)(82±10 vs 85±9 mmHg; p=0,003) and higher levels of glucose (123±48 vs 146±67 mg/dL; p=0,003), with lower prevalence of CHD (81% vs 67%; p=0,010). During the follow-up of 1,99±0,54 years was noticed a gradual increase of blood level of estrone (V1=25±13, V2=31±14, V3=33±17 pg/mL; p<0,01). The incidence of cardiovascular events according to the blood levels of estrone =25 pg/mL was similar in the two groups and occurred during the follow-up period of 0,62±0,46 years. Were reported 14 deaths: 8 associated with CVD and 6 related to another causes. The Kaplan-Meier estimation curve showed a trend (p=0,074) of greater mortality for CVD according the blood level of estrone of =15 pg/mL. The age [OR=1,08 (IC95%:1,01-1,18);p=0,037], C-reactive protein [OR=1,24 (IC95%:1,03-1,50);p=0,024] and hypertension [6,22 (IC95%:1,86- 20,81);p=0,003] were independent variables for mortality. CONCLUSIONS: Blood level of estrone for readings of >=25 pg/mL, can be associated with smaller prevalence of CAD, but had no impact in cardiovascular events and mortality. We noticed a trend of greater mortality in women with estrone level lower than 15 pg/mL.
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Method development for determination and removal of the selected steroids from water sources in selected areas around the Vaal River in South Africa using High performance Liquid Chromatography, Macadamia Activated Carbon and Solid Phase Extraction

Khotha, Doctor Elias January 2018 (has links)
M. Tech (Department of Chemistry, Faculty of Applied and Computer Sciences) Vaal University of Technology. / A simple and rapid method for determination of estrone (E1) and β-estradiol (E2) was developed and validated using high performance liquid chromatography (HPLC). The solutions of standards and sample were prepared with distilled water. HPLC separation was performed in isocratic method 50/50 (water/methanol) using 4.6 mm x 250 mm id film thickness 5 µm) XDB-C18 capillary column, detector DAD, UV on 254 nm, temperature 20 ºC with flow rate of 2 mL/min, sample volume 20 µL and run time of 10 min. Calibration curves were linear between concentration range 1.0 - 15.0 ppm. The method was validated for limit of detection and quantification, linearity, precision, trueness and specificity. Also the method was applied to directly and easily to the analysis of the E1 and E2. Adsorption experiments were carried out in batch mode using multistirrer in a series of Erlenmeyer flasks of 50 ml capacity covered to prevent contamination having concentration ranges of E1 and E2 from 1 to 10 mg/L with adsorbent dose range 0.01 to 1 g at pH range 1 to 10 and temperature range 15°C to 35°C, placed on multistirrer. The results of the batch studies showed that simultaneous adsorption shows the maximum percent (91%) removal of E1 and (86 %) E2 at optimum temperature 25 °C of adsorbent dose 0.1 g, and pH 7. The mechanism, isotherms and kinetics of removal of two endocrine disrupting chemicals, estrone (E1) and β-estradiol (E2) by activated carbon adsorption were investigated in an agitated non-flow batch adsorption studies. Mathematical models were used to describe the adsorption phenomenon with the kinetic and thermodynamic parameters evaluated using the adsorption equilibrium data at varying temperatures. Higher adsorption rates were achieved at acidic to neutral pH ranges, with the sorption kinetic data showing a good fit to the pseudo second order rate equation and the Langmuir adsorption isotherm model for both E1 and E2. The Gibbs free energy were –16.68 kJ/mol and –17.34 kJ/mol for E1 and E2 respectively. The values of enthalpy for both E1 (84.50 kJ/mol) and E2 (90 kJ/mol) indicated a chemical nature of the sorption process. Both the isotherm and thermodynamic data obtained all supported the mechanism of adsorption of E1 and E2 to be mainly chemisorption’s supported by some physical attractions.
29

Heterogeneous photocatalytic degradation of organic pollutants in water over nanoscale powdered titanium dioxide. The photocatalytic degradation of organic compounds in water (Reactive Orange 16, Triclocarbon, Clopyralid and Estrogens (estrone, 17ß-estradiol, and 17α-ethinylestradiol)) was studied; the reaction kinetics and the effect of the operating parameters on the performance of the system were determined; a comparison with other advanced oxidation processes (O3, H2O2, UV) was also made.

Mezughi, Khaled M. January 2010 (has links)
Organic contaminants from industrial and/or domestic effluents may be harmful to humans directly or indirectly by degrading the quality of the aquatic environment. Consequently these contaminants must be reduced to levels that are not harmful to humans and the environment before disposal. Chemical, physical and biological methods exist for the removal of these pollutants from effluents. Among the available chemical methods, heterogeneous photocatalytic oxidation has been found particularly effective in removing a large number of persistent organics in water. In this study, photocatalytic degradation was explored for the removal of reactive azo-dye (textile dye), triclocarban (disinfectant), clopyralid (herbicide) and three endocrine disrupting compounds (EDCs) (estrone, 17ß-estradiol and 17α-ethinylestradiol) from synthetic effluents. The major factors affecting the photocatalytic processes including the initial concentration of the target compounds, the amount of catalyst, the light intensity, the type of catalyst, the electron acceptor, the irradiation time and the pH were studied. Other oxidation techniques including (O3, H2O2, UV) were also studied. Generally UV light is used in combination with titanium dioxide, as photocatalyst, to generate photoinduced charge separation leading to the creation of electron-hole pairs. The holes act as electron acceptors hence the oxidation of organics occur at these sites. These holes can also lead to the formation of hydroxyl radicals which are also effective oxidants capable of degrading the organics. The results obtained in this study indicated that photolysis (i.e. UV only) was found to have no effect on the degradation of reactive azo-dye (RO16). However, complete photocatalytic degradation of 20 mg/L (3.24×10-2 mM) RO16 was achieved in 20 minutes in the presence of 1g/L TiO2 Degussa P25 at pH 5.5. Comparison between various types of catalysts (i.e. Degussa P25, VP Aeroperl, Hombifine N) gave varied results but Degussa P25 was the most effective photocatalyst hence it was selected for this study. For RO16 the optimum catalyst concentration was 0.5 g/L TiO2 with initial concentration of 20 mg/L RO16. It was found that the disappearance of RO16 satisfactorily followed the pseudo first-order kinetics according to Langmuir-Hinshelwood (L-H) model. The rate constant was k= 0.0928 mol/min. Photodegradation of TCC was studied in 70%v acetonitrile: 30%v water solutions. UV light degraded TCC effectively and the reaction rates increased with decreasing initial concentration of TCC. UV/TiO2 gave unsatisfactory degradation of triclocarban (TCC) since only 36% were removed in 60 minutes with initial concentration of TCC 20 mg/L. The degradation of clopyralid and the EDCs was studied using three oxidation systems UV/TiO2, UV/H2O2 and O3. Complete degradation of clopyralid (3,6-DCP) was achieved with UV/TiO2 in about 90 minutes at an optimum catalyst concentration of 1g/L. Zero-order kinetics was found to describe the first stage of the photocatalytic reaction in the concentration range 0.078-0.521 mM. At pH 5 the rate constant was 2.09×10-6-4.32×10-7 M.s-1.Complete degradation of all the three EDCs was achieved with UV/H2O2 in 60 minutes at catalyst concentration of (2.94×10-2 M). On the other hand complete degradation of the EDCs was achieved in just 2 minutes with ozonation. For high concentration EDCs, TiO2/UV gave low efficiency of degradation as compared with ozone and H2O2/UV. First-order kinetics was found to describe the photocatalytic reaction of the EDCs. / Education Service Department of the Libyan Government
30

Heterogeneous photocatalytic degradation of organic pollutants in water over nanoscale powdered titanium dioxide : the photocatalytic degradation of organic compounds in water (Reactive Orange 16, Triclocarbon, Clopyralid and Estrogens (estrone, 17ß-estradiol, and 17α-ethinylestradiol)) was studied : the reaction kinetics and the effect of the operating parameters on the performance of the system were determined; a comparison with other advanced oxidation processes (O₃, H₂O₂, UV) was also made

Mezughi, Khaled M. January 2010 (has links)
Organic contaminants from industrial and/or domestic effluents may be harmful to humans directly or indirectly by degrading the quality of the aquatic environment. Consequently these contaminants must be reduced to levels that are not harmful to humans and the environment before disposal. Chemical, physical and biological methods exist for the removal of these pollutants from effluents. Among the available chemical methods, heterogeneous photocatalytic oxidation has been found particularly effective in removing a large number of persistent organics in water. In this study, photocatalytic degradation was explored for the removal of reactive azo-dye (textile dye), triclocarban (disinfectant), clopyralid (herbicide) and three endocrine disrupting compounds (EDCs) (estrone, 17ß-estradiol and 17α-ethinylestradiol) from synthetic effluents. The major factors affecting the photocatalytic processes including the initial concentration of the target compounds, the amount of catalyst, the light intensity, the type of catalyst, the electron acceptor, the irradiation time and the pH were studied. Other oxidation techniques including (O3, H2O2, UV) were also studied. Generally UV light is used in combination with titanium dioxide, as photocatalyst, to generate photoinduced charge separation leading to the creation of electron-hole pairs. The holes act as electron acceptors hence the oxidation of organics occur at these sites. These holes can also lead to the formation of hydroxyl radicals which are also effective oxidants capable of degrading the organics. The results obtained in this study indicated that photolysis (i.e. UV only) was found to have no effect on the degradation of reactive azo-dye (RO16). However, complete photocatalytic degradation of 20 mg/L (3.24×10-2 mM) RO16 was achieved in 20 minutes in the presence of 1g/L TiO2 Degussa P25 at pH 5.5. Comparison between various types of catalysts (i.e. Degussa P25, VP Aeroperl, Hombifine N) gave varied results but Degussa P25 was the most effective photocatalyst hence it was selected for this study. For RO16 the optimum catalyst concentration was 0.5 g/L TiO2 with initial concentration of 20 mg/L RO16. It was found that the disappearance of RO16 satisfactorily followed the pseudo first-order kinetics according to Langmuir-Hinshelwood (L-H) model. The rate constant was k= 0.0928 mol/min. Photodegradation of TCC was studied in 70%v acetonitrile: 30%v water solutions. UV light degraded TCC effectively and the reaction rates increased with decreasing initial concentration of TCC. UV/TiO2 gave unsatisfactory degradation of triclocarban (TCC) since only 36% were removed in 60 minutes with initial concentration of TCC 20 mg/L. The degradation of clopyralid and the EDCs was studied using three oxidation systems UV/TiO2, UV/H2O2 and O3. Complete degradation of clopyralid (3,6-DCP) was achieved with UV/TiO2 in about 90 minutes at an optimum catalyst concentration of 1g/L. Zero-order kinetics was found to describe the first stage of the photocatalytic reaction in the concentration range 0.078-0.521 mM. At pH 5 the rate constant was 2.09×10⁻⁶ ± 4.32×10⁻⁷ M.s⁻¹. Complete degradation of all the three EDCs was achieved with UV/H₂O₂ in 60 minutes at catalyst concentration of (2.94×10⁻² M). On the other hand complete degradation of the EDCs was achieved in just 2 minutes with ozonation. For high concentration EDCs, TiO₂/UV gave low efficiency of degradation as compared with ozone and H2O2/UV. First-order kinetics was found to describe the photocatalytic reaction of the EDCs.

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