Thesis (Ph. D.)--UCLA, 2008. / Vita. Description based on print version record. Includes bibliographical references (leaves 76-89).

Thesis (Ph.D.)--University of Western Australia, 2008.

Thesis (M. S.)--University of North Carolina at Greensboro, 2006. / Title from PDF title page screen. Advisor: Cheryl Lovelady; submitted to the School of Human Environmental Sciences. Includes bibliographical references (p. 51-55).

Thesis (Ph. D.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains viii, 113 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 88-113).

O cobalto é um dos principais componentes das ligas metálicas fundidas amplamente utilizadas na odontologia. Ele é considerado o constituinte de 45 a 70% de inúmeros trabalhos protéticos. Há evidência de elementos metálicos causarem toxicidade sistêmica e local. Este trabalho teve como objetivo, avaliar os efeitos do cobalto no epitélio juncional, epitélio adamantino, epitélio da gengiva inserida e ligamento periodontal do 1° molar superior do rato, durante a lactação. Para tal, foram utilizados ratos com 1 dia de vida pós-natal, cujas mães receberam 300mg de cloreto de cobalto por litro de água destilada no bebedouro (grupo tratado -T) e ratos cujas mães não receberam CoCl2 (grupo controle - C), durante toda a lactação. Ao final de 21dias, os filhotes foram sacrificados com sobredosagem anestésica. As cabeças foram separadas e fixadas em solução de alfac (álcool 80%- 85ml, formalina 10ml e ácido acético 5ml) incluídas em parafina e os cortes frontais seriados foram corados com hematoxilina e eosina. Os cortes foram focalizados ao microscópio de luz (100X), munido de uma câmara clara. Os núcleos das células dos tecidos estudados foram projetados sobre o papel com aumento final de 1000X e 50 núcleos de cada estrutura foram contornados com lápis preto para posterior medição do diâmetros maior (D) e menor (d). Uma vez determinados os diâmetros, foram estimados os seguintes parâmetros cariométricos: diâmetro geométrico médio, relação entre D/d, perímetro, área, volume, relação entre volume e área, excentricidade, coeficiente de forma e índice de contorno. Neste trabalho também foi utilizada uma grade impressa sobre papel. As imagens obtidas foram desenhadas sobre a grade. A grade pode ser usada tanto para contar pontos sobre uma determinada estrutura histológica bem como para contar intersecções entre duas estruturas contíguas, bastando para isso, no primeiro caso, considerar o número de pontos que caem sobre a estrutura em estudo, ou, no segundo caso, o número de vezes em que as superfícies vizinhas cortam a linha curva. Com a finalidade de se avaliar o volume citoplasmático, o volume celular, a relação núcleo/citoplasma, a densidade numérica celular, a relação superfície externa/camada basal, a espessura das camadas epiteliais e a densidade de superfície, foi utilizada ora a contagem de pontos ora o número de intersecções e aplicados às equações estereológicas apropriadas para cada uma dessas variáveis. Todos os dados colhidos foram submetidos à estatística não paramétrica - Teste de Wilcoxon-Mann-Whitney. Os núcleos dos tecidos estudados mostraram valores diminuídos, após cariometria, para os diâmetros maior, menor e médio; volume, área, perímetro e relação volume/área. Estereologicamente foi possível observar, no epitélio juncional, epitélio adamantino e no epitélio da gengiva inserida, células menos volumosas com citoplasma mais escasso levando a um maior número de células por mm3 de tecido. O ligamento periodontal também se apresentou desorganizado e com fibras de menor tamanho. Neste estudo, o cobalto ocasionou um quadro de hipotrofia epitelial, indicando uma ação direta nos epitélios juncional e adamantino, epitélio da gengiva inserida bem como no ligamento periodontal. / Cobalt is one of the main components of cast metal alloys broadly used in dentistry. It is the constituent of 45 to 70% of numerous prosthetic works. There is evidence that metal elements cause systemic and local toxicity. The purpose of the present study is to evaluate cobalt effects on the junctional epithelium, adamantine epithelium, inserted gum epithelium, and periodontal ligament of the superior first molar in rats, during lactation. To do this, 1-day old rats were used, whose mothers received 300mg of cobalt chloride per liter of distilled in the drinker (treated group T) and rats whose mothers did not receive CoCl2 (control group C), during lactation. After 21 days, the rat pups were killed with an anesthetic overdose. The heads were separated and fixed in an alfac solution (80% alcohol-85ml, formaline-10ml, and acetic acid-5ml), embedded in paraffin and stained with hematoxylin and eosin. The cuts were viewed under a light microscope (100X) with a clear chamber. The nucleus of the studied tissue cells were projected on paper with a final increase of 100X. Fifty nuclei from each structure were outlined with a black pencil so that the greater (D) and smaller (d) diameters could be measured. After determining the diameters, the following cariometric parameters were established: mean geometric diameter, D/d relation, perimeter, area, volume, volume/area relation, eccentricity, form coefficient, and contour index. This study also used a grid printed on paper. The images obtained were drawn over the grid, which was used to count points over a certain histological structure as well as to count intersections between two contiguous structures. All that was needed, in the first case, was to consider the number of points located over the studied structure, or, in the second case, the number of times that neighboring surfaces cut the curve line. With the aim to evaluate the cytoplasmic volume, cellular volume, cytoplasm/nucleus relation, cellular numeric density, external surface/basal layer relation, the thickness of epithelial layers, and surface density, point counting was used at times and, at others, the number of intersections was considered and applied to the appropriate stereological equations for each variable. All the collected data were subjected to non-parametric statistics Wilcoxon-Mann-Whitney Test. The nuclei of the studied tissues showed reduced values after cariometry for: greater, smaller, and mean diameter; volume; area; perimeter; and volume/area relation. Stereologically, it was observed, in the junctional epithelium, adamantine epithelium, and in the inserted gum epithelium, cells with less volume and with scarce cytoplasm, which caused a greater number of cells per mm3 of tissue. The periodontal ligament was also disorganized and with smaller fibers. In this study, cobalt caused epithelial hypertrophy symptoms, indicating a direct action on the junctional and adamantine epithelium, inserted gum epithelium, as well as on the periodontal ligament.

Made available in DSpace on 2014-06-11T19:28:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-09-08Bitstream added on 2014-06-13T20:37:14Z : No. of bitstreams: 1 queiroz_eo_me_botfmvz.pdf: 212466 bytes, checksum: 09c0965bc5e5c2e8c6703a849ea0a63f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / Como em toda produção leiteira, temos que otimizar o sistema produtivo, visando obter os maiores rendimentos financeiros com o menor dispêndio de recursos, sem contanto, perder a qualidade do produto e prejudicar a saúde e bem-estar dos animais. O objetivo do trabalho foi avaliar o efeito do sistema de alimentação sobre a produção de leite, dinâmica do peso e condição corporal, infecção parasitária e análise econômica entre os sistemas. No grupo 1 (P), 14 ovelhas da raça Bergamácia foram mantidas em pasto de Panicum maximum cv. Tanzânia e no grupo 2 (C), 17 ovelhas da mesma raça foram confinadas, alimentados com silagem de milho e concentrado na proporção 85:15% no terço final da gestação e 65:35%, durante a lactação. Os cordeiros foram separados das mães 48h00 pós-parto, e as ovelhas foram ordenhadas mecanicamente duas vezes ao dia, às 4h00 e 14h00, e a produção de leite mensurada diariamente, por sessenta dias. Não houve diferença entre os tratamentos quanto à produção de leite, as ovelhas do confinamento apresentaram-se mais pesadas que as mantidas em pasto por todo o período da lactação, não houve diferença para condição corporal ao parto e o número de ovos por grama de fezes das ovelhas mantidas em pasto foi maior que das ovelhas confinadas durante o periparto, ao parto, lactação e fim de lactação. / As on every milk farm, it is necessary to optimize the production system, aiming to obtain the highest financial revenues with the lowest cost, provided that quality of products, as well as animal health and welfare are maintained. Two groups of Bergamasca sheep were used. 14 animals were grazed and 17 were penned during the final end of pregnancy, and 60 days period of lactation. The objective of this work was to evaluate the effect of feeding on milk production, body weight and corporal condition dynamics, parasitic infection and economic analysis between production systems. Group 1 (P): animals grazed on Panicum maximum var. Tanzania; and Group 2 (C): penned animals fed with corn silage and concentrate diet at 85:15% ratio at the third end of gestation an 65:35% ratio during lactation. Lambs were separated from mothers 48 hours after parturition. Sheep were mechanical milked and milk production was measured twice a day, at 4:00 and 14:00 hours. There was no difference between treatments for milk production and feedlot ewes presented higher live weight than that kept at pasture during the whole lactation. It was not observed difference for body condition at lambing. Ewes kept at pasture presented higher values of eggs per gram of faeces than feedlot ewes from pre-lambing to end lantation.

Há evidência de elementos metálicos causarem toxicidade sistêmica e local. Este trabalho teve como objetivo, avaliar os efeitos do zinco no epitélio adamantino, epitélio juncional, gengiva inserida e ligamento periodontal do 1° molar superior do rato, durante a lactação. Para tal, foram utilizados ratos com 1 dia de vida pós-natal, cujas mães receberam 300 mg de cloreto de zinco (ZnCl2) por litro de água destilada no bebedouro (grupo tratado - T) e ratos cujas mães não receberam o ZnCl2 (grupo controle - C), durante toda a lactação. Ao final de 21dias, os filhotes foram sacrificados com sobredosagem anestésica. As cabeças foram separadas e fixadas em solução de alfac (álcool 80% - 85ml; formalina - 10ml e ácido acético - 5ml) incluídas em parafina e os cortes frontais seriados foram corados com hematoxilina e eosina. Os cortes foram focalizados ao microscópio de luz (100X), munido de uma câmara clara. Os núcleos das células dos tecidos estudados foram projetados sobre o papel com aumento final de 1000X e 50 núcleos de cada estrutura foram contornados com lápis preto para posterior medição do diâmetros maior (D) e menor (d). Uma vez determinados os diâmetros, foram estimados os seguintes parâmetros cariométricos: diâmetro geométrico médio, relação D/d, perímetro, área, volume, relação entre volume e área, excentricidade, coeficiente de forma e índice de contorno. Neste trabalho também foi utilizada uma grade impressa sobre papel. As imagens obtidas foram desenhadas sobre a grade. A grade pode ser usada tanto para contar pontos sobre uma determinada estrutura histológica bem como para contar intersecções entre duas estruturas contíguas, bastando para isso, no primeiro caso, considerar o número de pontos que caem sobre a estrutura em estudo, ou, no segundo caso, o número de vezes em que as superfícies vizinhas cortam a linha curva. Com a finalidade de se avaliar o volume citoplasmático, o volume celular, a relação núcleo/citoplasma, a densidade numérica celular, a relação superfície externa/camada basal, a espessura das camadas epiteliais e a densidade de superfície, foram utilizadas ora a contagem de pontos, ora o número de intersecções e aplicados às equações estereológicas apropriadas para cada uma dessas variáveis. Todos os dados colhidos foram submetidos à estatística não paramétrica Teste de Wilcoxon - Mann - Whitney. Os núcleos dos tecidos estudados mostraram valores diminuídos, após cariometria, para os diâmetros maior, menor e médio; perímetro, área, volume e relação volume/área. Estereologicamente foi possível observar, no epitélio juncional, epitélio adamantino e no epitélio da gengiva inserida, células menos volumosas, levando a um maior número de células por mm3 de tecido. O ligamento periodontal também se apresentou desorganizado e com fibras de menor tamanho. Pode-se concluir que zinco trouxe alterações nos epitélios juncional e adamantino, gengiva inserida bem como no ligamento periodontal, após avaliações morfométricas e estereológicas. / There is evidence that metal elements cause systemic and local toxicity. The purpose of the present study is to evaluate zinc effects on the adamantine epithelium, junctional epithelium, inserted gum and periodontal ligament of the superior first molar of rat, during lactation. To do this, 1- day old rats were used, whose mothers received 300 mg of zinc chloride (ZnCl2) per liter of distilled in the drinker (treated group T) and rats whose mothers did not receive ZnCl2 (control group C), during lactation. After 21 days, the rat pups were killed with an anesthetic overdose. The heads were separated and fixed in an alfac solution (80% alcohol - 85ml, formaline - 10ml, and acetic acid - 5ml), embedded in paraffin and stained with hematoxylin and eosin. The cuts were viewed under a light microscope (100X) with a clear chamber. The nucleus of the studied tissue cells were projected on paper with a final increase of 1000X and fifty nuclei from each structure were outlined with a black pencil so that the greater (D) and smaller (d) diameters could be measured. After determining the diameters, the following cariometric parameters were established: mean geometric diameter, D/d relation, perimeter, area, volume, volume/area relation, eccentricity, form coefficient, and contour index. This study also used a grid printed on paper. The images obtained were drawn over the grid, which was used to count points over a certain histological structure as well as to count intersections between two contiguous structures. All that was needed, in the first case, was to consider the number of points located over the studied structure, or, in the second case, the number of times that neighboring surfaces cut the curve line. With the aim to evaluate the cytoplasmic volume, cellular volume, cytoplasm/nucleus relation, cellular numeric density, external surface/basal layer relation, the thickness of epithelial layers, and surface density, point counting was used at times and, at others, the number of intersections was considered and applied to the appropriate stereological equations for each variable. All the collected data were subjected to non - parametric statistics Wilcoxon - Mann - Whitney Test. The nuclei of the studied tissues showed reduced values after cariometry for: greater, smaller, and mean diameter; perimeter, area, volume and volume/area relation. Stereologically, it was observed, in the junctional epithelium, adamantine epithelium, and in the inserted gum epithelium, cells with less volume, which caused a greater number of cells per mm3 of tissue. The periodontal ligament was also disorganized and with smaller fibers. It was possible to conclude that zinc caused alterations in the adamantine epithelium, junctional epithelium, inserted gum and periodontal ligament, after morphometric and stereological evaluations.

Acetonemia is a metabolic disorder common among dairy cattle in the period from 10 days to six weeks post partum. It is during this time that milk production is at its maximum and in addition, the cow is beginning to exhibit regular estrous cycles. Thus, the profound demands for the precursors of milk production are superimposed upon a relatively unstable endocrine environment. The initial objective of this study was a clarification of the interactions between estrogens and endogenous substrates of glucose metabolism in the lactating cow. Since estrogen levels during the bovine estrous cycle had not been convincingly reported at the outset of this work, their measurement was the subject of the first experiment. Both estradiol and estrone exhibited peaks on the two days prior to the day of standing heat. These findings were later substantiated with the appearance of reports where plasma estrogen levels were measured by competitive protein binding and radioimmunoassay. A significant decline in plasma amino nitrogen concentration occurred after the estrogen peak, the decrease being reflected in marked reductions in the concentrations of threonine, methionine, proline and the branched chain amino acids. A notable hypoglycemia occurred somewhat later than the decline in amino acids. These findings were rationalized in terms of increased uterine and mammary uptake and/or decreased tissue mobilization of amino acids which may have given rise to the hypoglycemia as a result of decreased availability of glucogenic substrate. A possible mechanism of decreased tissue mobilization of amino acids was considered to be the inhibition by estrogens of adrenal glucocorticoid output, since glucocorticoids play a major role in regulating amino acid balance in peripheral tissues. In addition, the efficacy of glucocorticoid therapy in the treatment of bovine acetonemia is well recognized. With these considerations in mind, the role of estrogens in the modification of ACTH-stimulated glucocorticoid secretion was assessed in two further experiments. Following suppression of endogenous ACTH secretion by dexametha-sone, both estrogen treated and non-estrogen treated cows were subjected to stimulation with incremental doses of exogenous ACTH. At all levels of ACTH stimulation, estrogen treatment resulted in reduced response when measured in terms of plasma glucocorticoid concentrations. However, estrogen treatment had no effect on plasma binding of glucocorticoids. The concentrations measured were, therefore, a direct reflection of glucocorticoid activity. In the second experiment to test adrenal inhibition by estrogens, plasma ACTH and glucocorticoid levels were measured during the estrous cycles of lactating cows. For this purpose, a radioimmunoassay for ACTH was developed, providing a sensitive, reproducible method for the measurement of this hormone in bovine plasma. A significant increase in circulating ACTH concentration was seen during the estrogenic phase of the estrous cycle. No such increase was noted in the concentration of glucocorticoids, levels fluctuating within the normal, low range. This result implied that during the estrogenic phase of the estrous cycle, inhibition of glucocorticoid secretion by estrogens resulted in a compensatory rise in circulating ACTH concentration, bringing the glucocorticoid level back to normal. The results of these experiments are discussed with reference to the possible role of alterations in endocrine balance in the etiology of bovine acetonemia. / Land and Food Systems, Faculty of / Graduate

The aim of the work was to evaluate significant changes in body composition in Czech breastfeeding women during lactation and to confront them with the already available results of other similar studies. For this purpose, 10 female participants of the longitudinal study were selected. Body composition was determined by bioimpedance spectroscopy with a Fresenius Body Composition Monitor. Furthermore, anthropometric methods were used to evaluate the basic body parameters and compare their dependent loss with the values measured by BCM. The measurement was repeated in four periods - 3 weeks, 3 months, 6, and 9 months after delivery. During the observed period, an overall decrease in median weight of 4,2 kg was observed in lactating women. The median weight 9 months postpartum was still 1,2 kg greater than the median weight before pregnancy. No statistically significant differences in body composition were found during lactation. Human milk volume correlated positively with age of women (p = 0,0404; r = 0,3386), negatively with calf circumference (p = 0,0313; r = -0,3545), chin skinfold (p = 0,0198; r = -0,3816), triceps skinfold (p = 0,0905; r = -0,3302), LTI (p = 0,0216; r = -0,3767) and Cm (p = 0,0490; r = -0,3260). Correlations were also found between milk volume and some values needed to calculate...

Periconceptional heat stress is known to reduce the likelihood of establishing pregnancy; however, some conceptuses will survive. Of the pregnancies that continue to term, a proportion will be heifers which are retained as replacement animals. Alterations that occur as a result of exposure to thermal stress during such critical stages in development likely result in differential performance between the heat stress-conceieved (HSC) cows and thermoneutral-conceived (TNC) cows. National Dairy Herd Improvement Association data was obtained from Dairy Records Management Systems. Records (n =14,189,891) included cows born between 1977 and 2010 in FL, GA, SC, MS, LA, AL, and TX. Records were edited to include only Holsteins born between 2000 and 2010 (n = 704,419). Conception dates were calculated by subtracting 276 d from the recorded birth date. Records for cows conceived within the months of June, July, and August were retained as HSC cows; cows conceived within the months of December, January, and February were retained as TNC contemporaries. Significant differences (P<0.01) in mature-equivalent milk yield were observed in all first lactation cows, and in cows that were retained within one herd for three lactations. In the latter group alterations in milk compositions were statistically significant (P<0.01), but not biologically so. Furthermore, significant differences (P<0.01) in days open were observed in cows retained within one herd for three lactations. The effects of periconceptional heat stress were particularly noticeable during seasonal comparisons, with HSC cows seemingly having an advantage in subsequent episodes of heat stress. / Master of Science