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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.
11

Ontogeny of Adenosine Deaminase in the Mouse Decidua and Placenta: Immunolocalization and Embryo Transfer Studies

Knudsen, T B., Blackburn, M. R., Chinsky, J. M., Airhart, M J., Kellems, R. E. 01 January 1991 (has links)
This study has determined the cellular site of adenosine deaminase (ADA) expression in the mouse during development from Days 5 through 13 (day vaginal plug was found = Day 0) of gestation. Developmental expression of ADA progressed in two overlapping phases defined genetically (maternal vs. embryonal) and according to region (decidual vs. placental). In the first phase, ADA enzyme activity increased almost 200-fold in the antimesometrial region (decidua capsularis + giant trophoblast cells) from Days 6 through 9 of gestation but remained low in the mesometrial region. Immunohistochemical staining revealed a major localization of ADA to the secondary decidua. In the second phase, ADA activity increased several-fold in the placenta (labyrinth + basal zones) from Days 9 through 13 of gestation but remained low in the embryo proper. Immunohistochemical staining revealed a major localization of ADA to secondary giant cells, spongiotrophoblast, and labyrinthine trophoblast. Regression of decidua capsularis and growth of the spongiotrophoblast population accounted for an antimesometrial to placental shift in both ADA enzyme activity and a 40-kDa immunoreactive protein band. To verify a shift from maternal to fetal expression, studies were performed with two strains of mice (ICR, Eday) homozygous for a different ADA isozyme (ADA-A, ADA-B). Blastocysts homozygous for Adab were transferred to the uterus of pseudopregnant female recipients homozygous for Adaa. The isozymic pattern in chimeric embryo-decidual units analyzed at Days 7, 9, 11, and 13 revealed a predominance of maternal-encoded enzyme at Days 7 through 11 of gestation and a shift to fetal-encoded enzyme by Day 13. Thus, maternal expression of ADA in the antimesometrial decidua may play a role during establishment of the embryo in the uterine environment, whereas fetal expression of ADA in the trophoblast might be important to placentation.
12

Medidas de indicadores de estresse oxidativo e de remodelamento cardíaco em camundongos expostos à poluição atmosférica ambiental durante o desenvolvimento embrionário e pós-natal / Measurements of oxidative stress indicators and of cardiac remodeling in mice exposed to urban air pollution during embrionary and postnatal development.

Rodrigues, Nilsa Regina Damaceno 26 March 2007 (has links)
A poluição atmosférica de São Paulo (SP) pode provocar alterações cardiovasculares em seres humanos e animais experimentais, com maior vulnerabilidade em crianças e fetos. O mecanismo fisiopatológico que explicaria a relação entre a exposição aos poluentes e doenças cardiovasculares não está totalmente estabelecido, sendo que o estresse oxidativo pode estar ligado ao dano e morte celular. Há evidências de que o dano oxidativo pelo mecanismo da peroxidação lipídica pode estar relacionado às causas de diversas cardiovasculopatias. Estudamos o efeito da exposição ao ar ambiental nos níveis de peroxidação lipídica no coração de camundongos nos períodos pré e pós-natal. Os animais foram mantidos em duas câmaras de exposição, uma recebendo ar ambiente e outra ar filtrado, em quatro diferentes grupos: 1) LL: gestados e crescidos em câmara com ar filtrado, 2) PP: gestados e crescidos em câmara com ar poluído de SP, 3) PL: gestados na câmara poluída e crescidos na limpa, e 4) LP: gestados na câmara limpa e crescidos na poluída. A peroxidação lipídica do miocárdio foi avaliada tanto pelo método TBA como por imunohistoquímica para 15-F2t-isoprostano. As concentrações de malondialdeído (MDA, indicador de peroxidação lipídica) foi maior nos animais PP quando comparados aos LL (p = 0,004) e PL (p = 0,026), e não mostrou diferença significativa em relação ao grupo LP (p = 0,894). Os valores de MDA para animais PL e LP mostraram-se equivalentes (p = 0,168). Chama a atenção que o grupo PL apresentou um valor de MDA maior que o LL (p = 0,026). A fração de volume de miocárdio marcada imunohistoquimicamente para 15- F2t-isoprostano apresentou valores maior em PL (p = 2,884x10-5), LP (p = 6,632x10-6) e PP (p = 5,45x10-8) que em LL. O valor de PP foi maior que os de PL e LP (p = 3,661x10-4 e 1,058x10-3, respectivamente), sendo esses últimos equivalentes entre si (p = 0,624). A análise ultra-estrutural mostrou de maneira consistente a presença de lisossomos secundários contendo estruturas lipídicas membranosas nos grupos LP e PP. A porcentagem média de arteríolas com área entre 200 e 1000 ?m² em relação ao número total de vasos de cada grupo foi maior no grupo PP do que nos grupos LL e PL (p=0,0387 e p=0,0362, respectivamente). Estes resultados sugerem que existem altos níveis de peroxidação lipídica no tecido cardíaco dos animais expostos ao ar ambiental de SP. Chama a atenção o fato de que a exposição intra-uterina ter implicado em níveis maiores de estresse oxidativo na fase adulta, mesmo com a melhoria das condições ambientais. Comparam-se estes achados no miocárdio a outros resultados da literatura. / I t is well known that air pollution exposure in São Paulo can elicit cardiovascular injuries in humans and experimental animals and that children and fetuses appear to be particularly vulnerable. However, the mechanisms involved in this cardiovascular damage are not well understood. It has been suggested that the oxidative stress generated by air pollution exposure can trigger tissue injury. There is evidence supporting the idea that injury caused by lipid peroxidation may be related to the causes of several cardiovascular diseases. The aim of this study was to investigate the effects of prenatal and postnatal exposure to urban air pollution on the myocardium lipid peroxidation levels of adult mice. Myocardium lipid peroxidation was determined by the TBA method and by the detection of 15-F2t-isoprostan by immunohistochemical technique. The animals were placed in two chambers: one received air that passed through an air filter (clean) and the second received ambient air (polluted), according to four different exposure procedures: 1) Clean (CC): prenatal and postnatal in the clean chamber (control group), 2) Polluted (PP): prenatal and posnatal in the polluted chamber, 3) Polluted-clean (PC): prenatal in the polluted and posnatal in the clean chamber and 4) Clean-polluted (CP): prenatal in the clean and posnatal in the polluted chamber. The concentration of of malondialdehyde (MDA, a indicator of lipid peroxidation) was higher in group PP compared to CC (p = 0.004) and to PC (p = 0.026), and was not different of group CP (p = 0.894). The values of MDA for groups PC and CP turned to be equal (p = 0.168). Interestingly, group PC had a higher value of MDA than group CC (p = 0.026). The volume fraction of myocardium with detection of 15-F2tisoprostane is higher in PC (p = 2.884x10-5), CP (p = 6.632x10-6) and PP (p = 5.45x10-8) than in CC. The value of PP in higher than those of PC and CP (p = 3.661x10-4 and 1.058x10-3, respectively), while the latter two were equal to each other (p = 0.624). ). The mean ratio of arterioles wiht lumen area between 200 and 1000?m² to the total number of vessels in each group was higher in PP than in CC and PC (p=0.0387 and p=0.0362, respectively). These results, which suggest that exposure to air pollution is associated to higher levels of lipid peroxidation in the myocardium, are compared to other results previously published about respiratory and reproductive alterations related to pollution. Interestingly, the increased levels of lipid peroxidation in the PC group gives evidence that the prenatal exposure to urban air pollution can be linked to cardiovascular effects in adult life.
13

The inhibitory effect of trans fatty acids on maternal and neonatal essential fatty acid metabolism.

January 1997 (has links)
by Kwan Kwok Yiu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 145-155). / Acknowledgment --- p.i / Abstract --- p.ii / List of Tables --- p.vii / List of Figures --- p.x / List of Abbreviations --- p.xii / Chapter Chapter 1 --- Literature review / Chapter 1.1 --- Historical background --- p.1 / Chapter 1.2 --- Chemistry of trans and cis fatty acids --- p.3 / Chapter 1.3 --- Dietary source of trans fatty acids --- p.6 / Chapter 1.4 --- Consumption of trans fatty acids among Western countries --- p.9 / Chapter 1.5 --- Current health concern for excessive intake of trans fatty acids --- p.10 / Chapter 1.6 --- Metabolism of trans fatty acids --- p.13 / Chapter 1.6.1 --- Absorption --- p.15 / Chapter 1.6.2 --- Oxidation --- p.15 / Chapter 1.6.3 --- Incorporation --- p.16 / Chapter 1.6.4 --- Selectivity --- p.17 / Chapter 1.7 --- Impact of trans fatty acids on essential fatty acid metabolism --- p.19 / Chapter 1.8 --- Desaturation and elongation of trans fatty acids --- p.21 / Chapter 1.9 --- Trans fatty acids and neonatal growth --- p.23 / Chapter Chapter 2 --- Amount of trans fatty acids in Hong Kong fast foods / Chapter 2.1 --- Introduction --- p.25 / Chapter 2.2 --- Objective --- p.25 / Chapter 2.3 --- Materials and methods --- p.26 / Chapter 2.4 --- Results --- p.27 / Chapter 2.5 --- Discussion --- p.31 / Chapter Chapter 3 --- Cross-cultural study of trans fatty acids in human milk / Chapter 3.1 --- Introduction --- p.35 / Chapter 3.2 --- Objective --- p.35 / Chapter 3.3 --- Materials and methods --- p.36 / Chapter 3.4 --- Results / Chapter 3.4.1 --- Dietary information --- p.38 / Chapter 3.4.2 --- Fatty acid composition of Chinese and Canadian human milk --- p.40 / Chapter 3.4.3 --- Difference between Chinese and Canadian human milk --- p.40 / Chapter 3.4.4 --- Difference between Hong Kong and Chongqing Chinese human milk --- p.43 / Chapter 3.4.5 --- The change in milk fat and LCPUFA as lactation progresses --- p.43 / Chapter 3.5 --- Discussion / Chapter 3.5.1 --- Trans fatty acids in human milk --- p.46 / Chapter 3.5.2 --- Content of LCPUFA in human milk --- p.47 / Chapter 3.5.3 --- Content of 18:2n-6 in human milk --- p.48 / Chapter 3.5.4 --- Fat content in Hong Kong and Chongqing Chinese human milk --- p.49 / Chapter 3.6 --- Conclusion --- p.50 / Chapter Chapter 4 --- Trans fatty acids and maternal and neonatal essential fatty acid metabolism / Chapter 4.1 --- Introduction --- p.51 / Chapter 4.2 --- Objectives --- p.53 / Chapter 4.3 --- Materials and methods --- p.53 / Chapter 4.4 --- Results / Chapter 4.4.1 --- Experiment1 / Chapter 4.4.1.1 --- Relationship between the trans fatty acids in maternal diet and those in milk --- p.64 / Chapter 4.4.1.2 --- Relationship between the trans fatty acids in maternal diet and those in neonatal liver --- p.64 / Chapter 4.4.1.3 --- Content of 20:4n-6 in milk and in neonatal liver relative to that in maternal diet --- p.72 / Chapter 4.4.2 --- Experiment2 / Chapter 4.4.2.1 --- Amount of trans fatty acids in rat milk --- p.75 / Chapter 4.4.2.2 --- Trans fatty acids in rat liver phospholipids --- p.75 / Chapter 4.4.2.3 --- Linoleic acid (18:2n-6) content in rat and its relation to maternal diets --- p.86 / Chapter 4.4.2.4 --- Content of 20:4n-6 in rat milk --- p.86 / Chapter 4.4.2.5 --- Content of20:4n-6 in rat liver --- p.89 / Chapter 4.4.2.6 --- Suppression of the synthesis of 20:4t isomers in maternal and neonatal liver --- p.89 / Chapter 4.5 --- Discussion / Chapter 4.5.1 --- Relationship between fatty acid composition of diet and that of milk --- p.93 / Chapter 4.5.2 --- 20:4n-6 in rat milk --- p.95 / Chapter 4.5.3 --- Transfer of trans fatty acids from maternal diet to neonatal liver phospholipids --- p.98 / Chapter 4.5.4 --- The inhibitory effect of trans fatty acids on synthesis of 20:4n-6 in neonatal liver --- p.99 / Chapter 4.5.5 --- Effect of 18:2n-6 supplement on 20:4n-6 level of neonatal liver --- p.101 / Chapter 4.5.6 --- Suppression of 18:2n-6 supplement on synthesis of 20:4t isomers --- p.101 / Chapter 4.6 --- Conclusion --- p.104 / Chapter Chapter 5 --- Accumulation and turnover of trans fatty acids / Chapter 5.1 --- Introduction --- p.105 / Chapter 5.2 --- Objective --- p.105 / Chapter 5.3 --- Materials and methods --- p.106 / Chapter 5.4 --- Results / Chapter 5.4.1 --- Accumulation of trans fatty acids in liver and adipose tissue --- p.108 / Chapter 5.4.2 --- Selectivity of individual 18:2 trans isomersin liver and adipose tissue --- p.112 / Chapter 5.4.3 --- Turnover of trans fatty acids --- p.112 / Chapter 5.4.4 --- Accumulation and turnover of 18:lt in brain --- p.115 / Chapter 5.5 --- Discussion / Chapter 5.5.1 --- Accumulation of trans fatty acids in liver and adipose tissue --- p.120 / Chapter 5.5.2 --- Turnover of trans fatty acids --- p.122 / Chapter 5.5.3 --- Accumulation and turnover of trans fatty acidsin brain --- p.124 / Chapter 5.6 --- Conclusion --- p.125 / Chapter Chapter 6 --- In vivo Oxidation of trans fatty acids in rat / Chapter 6.1 --- Introduction --- p.126 / Chapter 6.2 --- Objective --- p.127 / Chapter 6.3 --- Materials and methods --- p.127 / Chapter 6.4 --- Results --- p.129 / Chapter 6.4.1 --- Apparent oxidation of saturated fatty acids --- p.136 / Chapter 6.4.2 --- Apparent oxidation of 18:lt relative to 18:ln-9 --- p.136 / Chapter 6.4.3 --- Oxidation of 18:2t isomers relative to 18:2n-6 --- p.137 / Chapter 6.4.4 --- Effect of 18:2n-6 supplement in PHCO diet on oxidation per se --- p.137 / Chapter 6.5 --- Discussion --- p.138 / Chapter 6.5.1 --- Oxidation of 18:lt and 18:2t isomers --- p.139 / Chapter 6.5.2 --- Effect of 18:2n-6 supplement on oxidation per se --- p.140 / Chapter 6.6 --- Conclusion --- p.141 / General conclusion --- p.142 / References --- p.145
14

Teratogenic Potential of Atrazine and 2,4-D Using Fetax

Morgan, M. K., Scheuerman, Phillip R., Bishop, C. S., Pyles, Rebecca A. 07 June 1996 (has links)
The teratogenic potential of commercial formulations of atrazine (40.8%) and 2,4-D was evaluated using FETAX (frog embryo teratogenic assay--Xenopus). Because these herbicides have been detected in ground and surface water, this study was designed to determine the adverse effects in buffer and natural water for both herbicides. All treatments showed a significant concentration-response effect on exposed embryos, except for the 2,4-D natural water sample. Atrazine (solubility of the commercial formula used 70 mg/L at 20 degrees C), compared to 2,4-D (solubility = 311 mg/L at pH = 1 and 25 degrees C), had a significantly greater teratogenic effect in both the buffer (atrazine EC50 = 33 mg/L, LC50 = 100 mg/L, TI = 3.03; 2,4-D EC50 = 245 mg/L, LC50 = 254 mg/L, TI = 1.04) and natural water samples (atrazine EC50 < 8 mg/L, LC50 = 126 mg/L; 2,4-D EC50 and LC50 > 270 mg/L). The 2,4-D EC50 and LC50 values for the buffer were similar at 245 mg/L and 254 mg/L. These similar values and the teratogenic index (TI) of 1.04 suggested that 2,4-D was more embryotoxic than teratogenic to frog embryos at high concentrations. Atrazine in natural water demonstrated a significantly greater EC50 (100% abnormality at 8 mg/L, the lowest test concentration) to frog embryos than the buffer experiment (EC50 = 33 mg/L). The extrapolated lowest observable adverse effect concentration (LOAEC) for the natural water experiment was 1.1 mg/L. These results suggest that atrazine toxicity is enhanced by the synergistic or additive effects of some component of the water or atrazine was already present in the sample. In contrast to atrazine, 2,4-D was less toxic in natural water than buffer. These results suggest that both atrazine and 2,4-D pose little threat, since their embryotoxicity and teratogenicity to frog embryos occur at high concentrations approaching their maximum solubility levels in water.
15

Medidas de indicadores de estresse oxidativo e de remodelamento cardíaco em camundongos expostos à poluição atmosférica ambiental durante o desenvolvimento embrionário e pós-natal / Measurements of oxidative stress indicators and of cardiac remodeling in mice exposed to urban air pollution during embrionary and postnatal development.

Nilsa Regina Damaceno Rodrigues 26 March 2007 (has links)
A poluição atmosférica de São Paulo (SP) pode provocar alterações cardiovasculares em seres humanos e animais experimentais, com maior vulnerabilidade em crianças e fetos. O mecanismo fisiopatológico que explicaria a relação entre a exposição aos poluentes e doenças cardiovasculares não está totalmente estabelecido, sendo que o estresse oxidativo pode estar ligado ao dano e morte celular. Há evidências de que o dano oxidativo pelo mecanismo da peroxidação lipídica pode estar relacionado às causas de diversas cardiovasculopatias. Estudamos o efeito da exposição ao ar ambiental nos níveis de peroxidação lipídica no coração de camundongos nos períodos pré e pós-natal. Os animais foram mantidos em duas câmaras de exposição, uma recebendo ar ambiente e outra ar filtrado, em quatro diferentes grupos: 1) LL: gestados e crescidos em câmara com ar filtrado, 2) PP: gestados e crescidos em câmara com ar poluído de SP, 3) PL: gestados na câmara poluída e crescidos na limpa, e 4) LP: gestados na câmara limpa e crescidos na poluída. A peroxidação lipídica do miocárdio foi avaliada tanto pelo método TBA como por imunohistoquímica para 15-F2t-isoprostano. As concentrações de malondialdeído (MDA, indicador de peroxidação lipídica) foi maior nos animais PP quando comparados aos LL (p = 0,004) e PL (p = 0,026), e não mostrou diferença significativa em relação ao grupo LP (p = 0,894). Os valores de MDA para animais PL e LP mostraram-se equivalentes (p = 0,168). Chama a atenção que o grupo PL apresentou um valor de MDA maior que o LL (p = 0,026). A fração de volume de miocárdio marcada imunohistoquimicamente para 15- F2t-isoprostano apresentou valores maior em PL (p = 2,884x10-5), LP (p = 6,632x10-6) e PP (p = 5,45x10-8) que em LL. O valor de PP foi maior que os de PL e LP (p = 3,661x10-4 e 1,058x10-3, respectivamente), sendo esses últimos equivalentes entre si (p = 0,624). A análise ultra-estrutural mostrou de maneira consistente a presença de lisossomos secundários contendo estruturas lipídicas membranosas nos grupos LP e PP. A porcentagem média de arteríolas com área entre 200 e 1000 ?m² em relação ao número total de vasos de cada grupo foi maior no grupo PP do que nos grupos LL e PL (p=0,0387 e p=0,0362, respectivamente). Estes resultados sugerem que existem altos níveis de peroxidação lipídica no tecido cardíaco dos animais expostos ao ar ambiental de SP. Chama a atenção o fato de que a exposição intra-uterina ter implicado em níveis maiores de estresse oxidativo na fase adulta, mesmo com a melhoria das condições ambientais. Comparam-se estes achados no miocárdio a outros resultados da literatura. / I t is well known that air pollution exposure in São Paulo can elicit cardiovascular injuries in humans and experimental animals and that children and fetuses appear to be particularly vulnerable. However, the mechanisms involved in this cardiovascular damage are not well understood. It has been suggested that the oxidative stress generated by air pollution exposure can trigger tissue injury. There is evidence supporting the idea that injury caused by lipid peroxidation may be related to the causes of several cardiovascular diseases. The aim of this study was to investigate the effects of prenatal and postnatal exposure to urban air pollution on the myocardium lipid peroxidation levels of adult mice. Myocardium lipid peroxidation was determined by the TBA method and by the detection of 15-F2t-isoprostan by immunohistochemical technique. The animals were placed in two chambers: one received air that passed through an air filter (clean) and the second received ambient air (polluted), according to four different exposure procedures: 1) Clean (CC): prenatal and postnatal in the clean chamber (control group), 2) Polluted (PP): prenatal and posnatal in the polluted chamber, 3) Polluted-clean (PC): prenatal in the polluted and posnatal in the clean chamber and 4) Clean-polluted (CP): prenatal in the clean and posnatal in the polluted chamber. The concentration of of malondialdehyde (MDA, a indicator of lipid peroxidation) was higher in group PP compared to CC (p = 0.004) and to PC (p = 0.026), and was not different of group CP (p = 0.894). The values of MDA for groups PC and CP turned to be equal (p = 0.168). Interestingly, group PC had a higher value of MDA than group CC (p = 0.026). The volume fraction of myocardium with detection of 15-F2tisoprostane is higher in PC (p = 2.884x10-5), CP (p = 6.632x10-6) and PP (p = 5.45x10-8) than in CC. The value of PP in higher than those of PC and CP (p = 3.661x10-4 and 1.058x10-3, respectively), while the latter two were equal to each other (p = 0.624). ). The mean ratio of arterioles wiht lumen area between 200 and 1000?m² to the total number of vessels in each group was higher in PP than in CC and PC (p=0.0387 and p=0.0362, respectively). These results, which suggest that exposure to air pollution is associated to higher levels of lipid peroxidation in the myocardium, are compared to other results previously published about respiratory and reproductive alterations related to pollution. Interestingly, the increased levels of lipid peroxidation in the PC group gives evidence that the prenatal exposure to urban air pollution can be linked to cardiovascular effects in adult life.

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