Thesis (Ph.D. in Clinical Sciences) -- University of Colorado at Denver and Health Sciences Center, 2005. / Typescript. Includes bibliographical references (leaves 100-112). Free to UCDHSC affiliates. Online version available via ProQuest Digital Dissertations;

Made available in DSpace on 2014-10-09T12:46:59Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:39Z (GMT). No. of bitstreams: 1 08289.pdf: 3549738 bytes, checksum: 91c401cfdc71f7626a33edd5a3a3e5ce (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

Made available in DSpace on 2014-10-09T12:46:59Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:39Z (GMT). No. of bitstreams: 1 08289.pdf: 3549738 bytes, checksum: 91c401cfdc71f7626a33edd5a3a3e5ce (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

A literatura tem alertado para a presença de imagens radiopacas em radiografias panorâmicas, adjacentes à coluna cervical, indicativas de calcificações na bifurcação da artéria carótida, representando indícios da presença de ateromas. Diferentes imagens radiopacas podem ser observadas na região cervical (anatômicas e patológicas), cujas características devem ser conhecidas. Existem, no entanto, considerações a serem feitas em relação a diferentes constituições físicas entre sexos, raças, e mesmo relacionadas ao tipo físico do indivíduo, que podem produzir projeções diferenciadas nas radiografias panorâmicas. A interpretação dessas radiografias requer uma compreensão da formação das imagens, já que a radiografia panorâmica é um sistema rotacional que resulta na formação de uma zona de nitidez dentro da qual as estruturas aparecem em foco e as que estivem para fora aparecerão borradas. O objetivo do trabalho foi avaliar a contribuição das telerradiografias, nas normas lateral e frontal, na identificação e localização de calcificações em tecidos moles, quando comparado com as observadas em radiografia panorâmica. Referências radiopacas em guta percha foram posicionadas unilateralmente, em três cabeças de cadáveres, procurando manter sempre no mesmo nível da bifurcação da artéria carótida comum, em diferentes estruturas, sítios de possíveis calcificações e foram obtidas três incidências radiográficas para cada peça anatômica. Assim, a amostra deste estudo foi composta por 27 radiografias panorâmicas, 27 telerradiografias em norma lateral e 27 telerradiografias em norma frontal, totalizando 81 radiografias. Estas imagens foram avaliadas por 05 examinadores para que identificassem qual a localização mais provável da referência radiopaca e se as telerradiografias em norma lateral e frontal auxiliaram no diagnóstico diferencial das calcificações, quando observadas na radiografia panorâmica. Os resultados obtidos apontaram que as telerradiografias em norma lateral e frontal não contribuem eficazmente na identificação e localização de radiopacidades na região cervical, e que a conformação anatômica interfere na observação da presença de radiopacidade na região cervical. / The literature has warned about the presence of radiopaque images in panoramic radiographs, adjacent to the spine, indicative of calcifications in the bifurcation of the carotid artery, representing signs of the presence of atheromas. Different radiopaque images can be observed in the cervical region (anatomic and pathologic), whose characteristics should be known. There are, however, considerations to be made with regard to the different physical constitutions between sexes, races, and even related to the physical type of the individual, which may produce differentiated projections in panoramic radiographs. Interpretation of these radiographs requires an understanding of the formation of the images, since the panoramic radiograph is a rotational system that results in the formation of a zone of nitidity within which the structures appear in focus and those that are outside of it appear blurred. The aim of the study was to evaluate the contribution of lateral and frontal teleradiographs to the identification and location of calcifications in soft tissues, when compared with those observed in panoramic radiographs. Radiopaque references in gutta percha were placed unilaterally on the heads of three cadavers, endeavoring at all times to keep to the same level as the bifurcation of the common carotid artery in different structures, sites of possible calcifications, and three radiographic incidences were obtained for each anatomic part. Thus, the sample of this study was composed of 27 panoramic radiographs, 27 lateral teleradiographs and 27 frontal teleradiographs, totaling 81 radiographs. These images were evaluated by 05 examiners so that they could identify which the most probable location of the radiopaque reference would be, and whether the lateral and frontal teleradiographs were a help in the differential diagnosis of the calcifications, when observed in the panoramic radiograph. The results obtained showed that the lateral and frontal teleradiographs did not contribute efficiently to the identification and location of radiopacities in the cervical region, and that the anatomic conformation interferes in the observation of the presence of radiopacity in the cervical region.

Estudos têm reportado o impacto periodontite na aterosclerose. Neste estudo verificamos a associação determinando alguns marcadores de risco para aterosclerose, e verificarmos a influência do tratamento periodontal sobre esses marcadores. Quarenta pacientes com periodontite e 40 sem periodontite foram incluídos. Colesterol Total, e frações, triacilglicerol (TG), níveis de citocinas, anticorpos anti-oxLDL, proteína C Reativa (PCR), contagem de leucócitos e neutrófilos, e índice de refração foram investigados. Interleucina (IL)-6, -8 e PCR, anticorpos anti-oxLDL, TG e contagem de leucócitos e neutrófilos foram maiores em pacientes com periodontite. Os pacientes com periodontite passaram por tratamento periodontal. Novas coletas foram feitas após 3, 6 e 12 meses após o tratamento. Um ano após o tratamento, as concentrações de TG, IL-6, -8, PCR, contagem de leucócitos e neutrófilos e anticorpos anti-oxLDL foram significantemente menores. Nossos resultados confirmam que o tratamento periodontal induz mudanças sistêmicas em vários marcadores de risco para aterosclerose. / Studies have reported the impact of periodontitis on atherosclerosis. In this study we verify the association by determining some of risk markers for atherosclerosis, and we verify the effect of periodontal treatment on these risk markers. Forty patients with chronic periodontitis and 40 without periodontal disease were included. Total cholesterol and fractions, triacyglycerol (TG), levels of cytokines, antibodies anti-oxLDL, C reactive protein (CRP), leukocyte and neutrophils count, and the non-linear index were investigated. Interleukin (IL)-6,-8 and CRP, antibodies anti-oxLDL, TG and leukocyte and neutrophils counts were higher in periodontitis patients. The patients with periodontitis underwent periodontal treatment. Additional samples were collected after 3, 6 and 12 months after treatment. One year after the treatment, TG, IL-6,-8, CRP, Leukocyte and neutrophils counts, anti-oxLDL antibody were significantly lower. Our results confirmed that the periodontal treatment induces systemic changes in several markers the risk for atherosclerosis.

Leptin is the prototypical adipokine that circulates in direct proportion to whole body adiposity. As such, serum leptin levels decrease when white adipose tissue depletes by calorie restriction whereas they increase as white adipose tissue expands by overnutri-tion. At both sides of the spectrum, i.e. too little and too much leptin, the adipokine con-tributes to vascular complications such as atherosclerosis and reproductive dysfunction. Mice that lack both leptin and the low density lipoprotein receptor (LDLR−/−;ob/ob) are an ideal model to study atherosclerosis as they present with atherosclerotic plaques in the aortic root and brachiocephalic artery. In this thesis, dose-dependent effects of re-combinant leptin administration from the subphysiological to physiological range on atherosclerotic plaque formation and fertility was studied in LDLR−/−;ob/ob mice. Lep-tin dose-dependently reduced plaque lesions and improved Leydig cell function and spermatogenesis. The effect of leptin treatment on atherosclerotic plaques was inde-pendently and significantly associated with improvements in lipid homeostasis and liver steatosis, as well as increased adiponectin. The beneficial effects of leptin treatment on several measures of fertility such as intratesticular testosterone, circulating follicle stim-ulating hormone, and seminiferous tubule morphology appeared to be direct and body weight-independent. Besides genetic leptin-deficiency, lipodystrophy (LD) patients and lipodystrophic mice were studied. LD is a leptin-deficient condition caused by the lack of subcutaneous white adipocytes leading to several metabolic complications including severe insulin resistance and hypertriglyceridemia. The effects of adipose tissue loss in LD on the adipokines chemerin, progranulin, and fibroblast growth factor 21 have not been investigated so far. Circulating levels of these three adipokines were all increased in LD patients as compared to weight- and age-matched controls. Furthermore, none of these adipokines was significantly regulated in 10 LD patients by leptin treatment over 6 months. In a mouse model of generalized LD, increased expression of these adipokines was found in various adipose tissue depots at the mRNA level providing first preliminary evidence as to the source of higher circulating levels in LD patients. Collec-tively, the findings of this thesis show for the first time dose-dependent beneficial ef-fects of leptin on atherosclerosis and reproductive function and provide new information about the association of LD with changes in various adipokines that have an established impact on metabolic function.

No description available.

The toxicity of elevated levels of very low density lipoproteins (VLDL, d < 1.006 g/ml) was investigated using porcine aortic endothelial cells in vitro. VLDL isolated from normal rat serum and added at elevated levels was as toxic as VLDL isolated from streptozotocin-induced diabetic rat serum. Injury was detected by scanning electron microscopy in 4-day-old primary cultures of endothelial cells after a 1 2 exposure to diabetic rat serum. Bleb formation and contraction was seen first in isolated cells ( 1 2 h), followed by cells at the periphery of the monolayer (1 h) and finally in cells throughout the monolayer (4 h). By 10 h few cells remained attached to the dish. A similar sequence of events occurred in 1-day-old cultures after a 3-h lag period. Serum from sucrose-fed as well as aged rats was also found to be toxic to endothelial cells in vitro. Elevated levels of VLDL were responsible for the toxicities of these sera. Scanning electron microscopy of the aortas from diabetic and sucrose-fed rats revealed endothelial desquamation, platelet and leukocyte attachment, fibrin deposition and the presence of microthrombi. The common occurrence of both micro- and macrovascular disease in diabetic, sucrose-fed, and aged rats and the toxicity of their serum in vitro suggest that elevated levels of VLDL may initiate vascular disease in these models.

M.S.

Thesis (Ph. D.)--University of Missouri--Columbia, 2001. / "May 2001." Typescript. Vita. Includes bibliographical references (leaves 176-195). Also available on the Internet.