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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.
191

Avaliação do tecido ósseo de sítios implantares em rebordos maxilares por meio de métodos radiográficos e da análise histomorfométrica / Assessment of the bone tissue of implant sites in maxillary ridges with radiographic methods and histomophometric analysis

Côrtes, Arthur Rodriguez Gonzalez 11 June 2014 (has links)
Um dos principais fatores que influencia os resultados da terapia de implantes dentários é a densidade do osso alveolar. A sua avaliação permitiria a predição do torque de inserção do implante levando a um planejamento preciso do tratamento. O presente estudo de coorte teve como objetivo definir e correlacionar características radiográficas e morfológicas do osso, e sua influencia no torque de inserção. Foram analisados dados demográficos, radiografias panorâmicas e tomografias computadorizadas por feixe cônico (TCFC) de um total de 25 pacientes que receberam 31 implantes. Amostras ósseas retiradas dos sítios implantares foram avaliadas com densitometria óssea, micro-tomografia computadorizada, e histomorfometria. A análise de escala de cinzas avaliada com a TCFC foi fortemente correlacionada com a microtomografia computadorizada (r=0,504, p=0,004) e com a histomorfometria (r=0,795, p=0,001). No entanto, os resultados da correlação de Spearman mostraram que o torque máximo de inserção foi fortemente correlacionado com a espessura cortical do rebordo (r=0,609, p=0,001). Os resultados indicam que o torque de inserção é influenciado principalmente pela camada cortical do osso alveolar. O trabalho propõe ainda uma classificação clínica de predição de torque, baseada em resultados de sensitividade e especificidade da combinação de variáveis diferentes. A TCFC de 14-bit foi indicada como confiável para avaliar a densidade do tecido ósseo alveolar através da escala de cinzas. / A main factor influencing dental implant therapy outcomes is the alveolar bone density. Its assessment would allow for prediction of implant insertion torque (IT), leading to a precise treatment planning. The present cohort study aimed to define and correlate imaging and morphometric bone features influencing IT. Demographics, panoramic radiographs and cone beam computed tomographic (CBCT) scans of a total of 25 patients receiving 31 implants were analyzed. Bone samples retrieved from implant sites were assessed with dual x-ray absorptiometry, micro-computed tomography, and histomorphometry. Grayscale analysis using CBCT was strongly correlated with micro-computed tomography and with histomorphometric analysis (r=0.795, p=0.001). However, Spearmans correlation results showed that peak IT was strongly correlated with ridge cortical thickness (r=.609, p=.001). These results indicate that IT is mainly influenced by the amount of alveolar cortical bone layer. This work further propose a clinical classification for IT prediction, based on findings of sensitivity and specificity of the combination of different variables. 14-bit CBCT was indicated as reliable to assess alveolar bone density using grayscale analysis.
192

Associação do tecido adiposo medular ósseo, massa óssea e a expressão do receptor tipo 1 dos IGFs em crianças e adolescentes obesos / Association of bone marrow adipose tissue, bone mass, and type 1 IGF receptor expression in obese children and adolescents

Darrigo, Emiliana Ribeiro 04 September 2017 (has links)
O tecido adiposo e ósseo tem uma íntima relação, desde a origem comum nas células tronco estromais derivadas da medula óssea. Sabe-se que o peso corporal tem estreita correlação com a massa óssea em seres humanos. Porém, ainda não é claro qual componente do peso corporal tem maior influência sobre o ganho de massa óssea e sobre a adiposidade na medula óssea, visto que tanto indivíduos com baixo peso, quanto os obesos, apresentam altas taxas de fraturas. O objetivo deste trabalho foi comparar crianças e adolescentes obesos e eutróficos em relação a composição óssea, adiposidade da medula óssea em coluna lombar (L3), expressão do Receptor tipo 1 de IGF (IGF1R) e concentrações séricas de IGF-I e buscar correlação entre estas variáveis. Para tanto foram avaliados crianças e adolescentes de 10 a 17 anos, divididos em grupo controle e grupo obeso. Esses grupos foram submetidos a avaliação antropométrica, densitometria óssea de coluna lombar e corpo total e ressonância magnética de coluna lombar e abdome total, além de dosagens séricas de parâmetros bioquímicos e hormonais. Os pacientes do grupo obeso apresentaram associação positiva da densidade mineral óssea tanto com massa gorda quanto com massa magra, enquanto que o grupo controle apresentou associação positiva da densidade mineral óssea apenas com a massa gorda. Não houve diferença entre os grupos quanto a adiposidade da medula óssea, nem quanto aos valores de IGF-I, IGFBP3 e expressão do gene do IGF1R. / The adipose and bone tissue has an intimate relationship, from the common origin in stromal stem cells derived from the bone marrow. It is known that body weight has a close correlation with bone mass in humans. However, it is still unclear which component of body weight has a greater influence on bone mass gain and adiposity in the bone marrow, since both individuals with low weight and obese have high fracture rates. The objective of this study was to compare obese and eutrophic children and adolescents in relation to bone composition, bone marrow adiposity in the lumbar spine (L3), expression of IGF type 1 receptor (IGF1R) and serum concentrations of IGF-I and to seek correlation between these variables. For this, children and adolescents between 10 and 17 years old were divided into control and obese groups. These groups were submitted to anthropometric evaluation, bone densitometry of the lumbar spine and total body and lumbar spine and total abdominal magnetic resonance, in addition to serum levels of biochemical and hormonal parameters. The patients in the obese group had a positive association of bone mineral density with both fat mass and lean mass while the control group showed a positive association of bone mineral density with fat mass only. There was no difference between the groups regarding bone marrow adiposity, nor regarding IGF-I, IGFBP3 and IGF1R gene expression.
193

Etude des relations os/muscle et projet de courbes de référence de la densité minérale osseuse et de la composition corporelle chez l’homme jeune : étude multicentrique française / Relationships between bone/muscle and project of reference curves of bone mineral density and body composition in young men : french multicenter study

Sutter, Thibault 24 May 2018 (has links)
Notre objectif à court terme est d’établir des courbes de référence Française de la densité osseuse (DMO) et de la composition corporelle masculine une fois que nous aurons toutes les données issues de tous les centres. Nous avons donc réalisé deux études préliminaires dans le cadre de ce projet dont les objectifs sont les suivants :A) Etudier les déterminants de la DMO corps entier mais aussi spécifiques de site osseux en lien avec les mesures de composition corporelle, de force musculaire et de l’activité physique chez l’homme jeune B) Cross-calibration in vitro des paramètres de densité osseuse et de composition corporelle mesurés par l’absorptiométrie bi-photonique à rayons X (DXA) afin d’établir les facteurs correctifs à appliquer in vivo dans le cadre de notre projet de courbe de référence chez l’homme jeune.Grâce à la DXA, notre étude a confirmé que la masse maigre était le facteur le plus important associé aux paramètres de la DMO sur tous les sites osseux étudiés et que la masse grasse avait un impact négatif sur la DMO. Aucune association n'a été trouvée entre activité physique et DMO. La force de préhension était significativement mais modérément corrélée avec la DMO. Concernant la cross-calibration, les résultats ont montré que l’oscillation des résultats entre les différents DXA des centres est un sujet de préoccupation pour les études multicentriques et en particulier pour l’évaluation de la composition corporelle. La cross-calibration nous a permis de calculer les facteurs correctifs à appliquer sur les données issues des centres impliqués. Afin de limiter ces variations, il serait souhaitable de mettre au point un fantôme corps entier standard qui serait utilisé pour les études multicentriques. / Our short-term goal is to establish French reference curves of bone mineral density (BMD) and body composition once we have data from all centers. We have therefore carried out two preliminary studies for this project whose objectives are as follows: A) To study the determinants of whole body BMD but also bone site specific in relation to measurements of body composition, muscle strength and physical activity in young men B) Cross-calibration in vitro of bone mineral density and body composition parameters measured by dual energy X-ray absorptiometry (DXA) in order to establish in vivo the correction factors to be used in our baseline project in young men. Using DXA, our study confirmed that lean mass was the most important factor associated with BMD parameters at all bone sites and fat mass had a negative impact on BMD. Grip strength was significantly but moderately correlated with BMD at all sites. No association was found between physical activity and BMD. Regarding cross-calibration, the results showed that the oscillation of the results between the different DXA centers is a problem for multicenter studies and in particular for the evaluation of body composition. Cross-calibration allowed us to calculate the corrective factors to be applied to the data from the centers involved. In order to limit these variations, it would be desirable to develop a standard whole-body phantom that would be used for multicentre studies.
194

HIV, antiretroviral therapy, pregnancy, lactation and bone health in Uganda

Nabwire, Florence January 2018 (has links)
Globally, ~17 million women and ~2.1 million children are living with HIV. Sub-Saharan Africa accounts for 70% of HIV-infected (HIV+) persons. Mother-To-Child Transmission of HIV (MTCT) during pregnancy, delivery and breastfeeding, is the main route of HIV infection in children. The World Health Organisation recommends lifelong antiretroviral therapy (ART) for all HIV+ pregnant and breastfeeding mothers to prevent MTCT, and breastfeeding for ≥24 months for optimal child health in resource limited settings (Option B+ strategy). Initiation of ART in HIV+ adults is associated with a 2-6% decrease in areal bone mineral density (aBMD) regardless of ART regimen, but data are limited in pregnant and lactating women. Tenofovir, a preferred first-line drug in Option B+ ART regimen, is associated with 1-2% greater decreases in aBMD. Pregnancy and lactation are associated with physiological changes in maternal bone mineral density, but most evidence shows that this is recovered after cessation of breastfeeding. The hypothesis of this thesis is that ART may accentuate the normal process of bone mobilisation during pregnancy and lactation, leading to bone loss that is not recovered in the mother and/or compromised infant growth and bone mineral accretion. The primary objective of this research was to investigate if HIV+ women experience greater reductions in bone mineral compared to HIV-uninfected (HIV-) counterparts. Two groups of pregnant women, 95 HIV+ on ART (Tenofovir-Lamivudine-Efavirenz, previously ART naïve) and 96 HIV- were followed prospectively in Kampala, Uganda. Data were collected at 36 wks gestation (PG36), 2 (PP2) and 14 wks postpartum (PP14). Dual-energy x-ray absorptiometry was used to measure bone phenotype (aBMD, bone mineral content (BMC), bone area (BA), and size-adjusted BMC (SA-BMC, adjusted for height or length, weight and BA) of the whole body (WB) and lumbar spine (LS) in mother-baby pairs, and total hip (TH) in mothers. The primary outcome was the difference between groups in % change (± SE) in maternal LS aBMD between PP2 and PP14. Secondary outcomes included changes in maternal markers of bone formation (P1NP and BAP) and resorption (CTX), serum 25-hydroxy vitamin D (25(OH)D), parathyroid hormone (PTH), plasma and urine concentrations of creatinine (Cr), calcium (Ca), phosphate (PO4) and magnesium (Mg), urine mineral:creatinine ratios, TmCa/GFR and TMP/GFR, respectively), breastmilk mineral composition (Ca, P, Na, K and Na/K ratio); and infant growth Z-scores and bone mineral. Statistical models were adjusted for potential confounders. Median maternal age was 24.5 (IQR 21.1, 26.9) yrs. Mean gestation was 40.9±1.8 wks and not significantly different between groups. All women were breastfeeding at PP2 and PP14. More HIV+ women reported exclusive breastfeeding (PP2: 82.9% v 58.7%, p=0.0008; PP14: 86.7% v 66.2%, p=0.002). Body weight was 4-5% lower in HIV+ women. By PP14, mean duration of ART was 29.3±5.1 wks, adherence was > 95%, and the median CD4 count was 403 (IQR 290-528) cells/mm3. Maternal aBMD decreased between PP2 and PP14 at all skeletal sites in both groups as expected in lactation. Reductions in LS aBMD were not significantly different between groups (-1.8±0.4% vs -2.5±0.4%, p=0.3). However, HIV+ women had a significantly greater reduction in TH aBMD which persisted after adjustment for body size (-3.7±0.3% vs -2.7±0.3%, p=0.04). Median serum 25(OH)D was 67.4 nmol/L (IQR 54.8, 83.7) at PG36 and 57.6 nmol/L (48.7, 70.1) at PP14 with no significant difference between groups. Changes in 25(OH)D and PTH from PG36 to PP14 were not significantly different between groups (25(OH)D: -13.9±4.1% vs -11.1±3.1%; PTH: +60.0±6.4% vs +57.6±6.4%; both p > 0.05). However, HIV+ women had 33-35% greater plasma PTH concentrations at both PG36 and PP14. Bone formation and resorption markers increased in both groups between PG36 and PP14. HIV+ women had greater increases (CTX: +74.6±5.9% vs +56.2±5.9%; P1NP: +100.3±5.0% vs +72.6±5.0%; BAP: +67.2±3.6% vs +57.1±3.6%, all p < 0.05). They also had a greater decrease in plasma Ca (-6.6±0.5% vs-3.8±0.5%, p≤0.0001) and greater increase in plasma phosphate (+14.4±2.0% vs +7.7±2.0%, p=0.02). Changes in plasma Cr and Mg, TmP/GFR and urine mineral:creatinine ratios were not significantly different between the groups. However, at both PG36 and PP14, HIV+ had significantly lower mean plasma Ca (PG36: -1.0±0.5%; PP14: -4.1±0.6%) and TmP/GFR (PG36: -11.4±3.1%; PP14: -7.2±3.0%) but higher PTH (PG36: +33.0±7.0%; PP14: +35.3±7.6%) compared to HIV- women (all p < 0.05). Mean breastmilk Ca decreased between PP2 and PP14, and the changes were not different between the groups (-19.9±3.0% vs -24.2±3.1%, p=0.3). There were no significant changes in breastmilk phosphorus (P) in both groups, but HIV+ women had significantly higher concentrations (PP2: +9.7±3.8%, p=0.01; PP14:+9.6±3.5 %, p=0.007). Breastmilk P was significantly correlated with maternal plasma [CTX] in a separate ANCOVA model (β = +0.13±0.04% per 1% increase in CTX, p=0.0003). Mean breastmilk Na, K concentrations and Na/K decreased between PP2 and PP14 in both groups. However, HIV+ women had a smaller decrease in breastmilk Na (-44.3±8.9% vs -72.6±9.0%, p=0.03). They also had a trend towards smaller reduction in Na/K ratio (-22.2±9.3% vs -46.6.6±9.5%, p=0.07). Babies born to HIV+ mothers (HIV-exposed infants, HEI) had significantly lower gains in weight +53.0±1.4% vs +57.5±1.4%, p=0.02) compared to HIV-unexposed infants (HUI), and also lower weight-for-age (-0.47±0.16, p=0.003) and length-for-age (-0.53±0.18, p=0.005) Z-scores at PP14. HEI had a slower gain in WB BMC (+51.2±1.9% vs +57.3±1.9%, p=0.02), but the difference was not significant after adjustment for body size (-6.0±3.5% vs -7.6±3.8%, p=0.2); showing that the bone mineral accretion was appropriate for achieved infant size. In contrast, HEI had a greater increase in LS BMC (+29.5±1.7% vs +24.4±1.7%, p=0.03), a difference which remained after size-adjustment (+9.4±5.8% vs +4.3±6.2%, p=0.02). This is the first study to compare changes in maternal aBMD and bone metabolism between HIV+ mothers on Option B+ ART and HIV- counterparts. The results show a greater reduction in TH aBMD in Ugandan HIV+ women on Option-B+ ART compared to HIV- in the first three months of lactation, consistent with their greater increases in bone turnover markers, lower TmP/GFR and plasma phosphate, and higher breastmilk phosphorus concentration. Also, HEI have slower growth and whole body bone mineral accretion compared to HUI. It is important to determine if these changes are temporary or have long-term consequences for the bone health of the mother and child.
195

Respostas densitométricas, morfofisiológicas e desempenho de frangos de corte tratados com água filtrada e não filtrada /

Amoroso, Lizandra. January 2009 (has links)
Orientadora: Silvana Martinez Baraldi Artoni / Banca: Nilce Maria Soares / Banca: Douglas Emygdio de Faria / Banca: Edivaldo Antônio Garcia / Banca: Otto Mack Junqueira / Resumo: A água é um recurso natural escasso que deve ser utilizada de forma racional e apresentar qualidade química, física e microbiológica. Neste contexto, o presente trabalho avaliou a densitometria óssea, os níveis séricos de cálcio e fósforo, a histologia, a microscopia eletrônica de varredura, a morfometria intestinal e renal, o desempenho de frangos de corte, a qualidade microbiológica e química da água de consumo em frangos de corte tratados com água filtrada e não filtrada. Observou-se que a densitometria óssea apresentou níveis crescentes aos 14 e aos 21 dias de idades, estabilizando-se aos 45 dias de idade. A densidade mineral óssea foi maior na epífise distal de aves que ingeriram água filtrada fazendo com que estas aves resistissem a uma maior pressão óssea nesta região em relação às aves que ingeriram água não filtrada. Os valores médios de cálcio sérico não apresentaram variações significativas entre os tratamentos analisados. Por outro lado, os níveis de fósforo sérico de aves tratadas com água filtrada foram menores em relação às que receberam água não filtrada. Na microscopia eletrônica de varredura, observou-se que enquanto a densidade dos vilos intestinais aumentou em aves que receberam água não filtrada, a integridade intestinal foi mantida em frangos tratados com água filtrada em resposta à sua condição microbiológica. Na análise macroscópica do intestino delgado e dos rins, não houve diferença entre os tratamentos para as medidas de comprimento, largura, peso absoluto e relativo dos órgãos. Na morfometria intestinal, observou-se que o comprimento das vilosidades e o número de células caliciformes não variaram entre os tratamentos. Entretanto, houve aumento na profundidade das criptas intestinais em aves que receberam água não filtrada provavelmente em função do aumento da taxa de turnover intestinal... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Water is a lean natural resource that must be used in a rational way and must be present chemical, physical and microbiological quality. In this context, the present work evaluated bone densitometry, serum levels of calcium and phosphorus, chicken performance, chemical, physical and microbiological quality of consumption water by chickens treated with filtered water and no filtered. It was observed that the bone densitometry presented crescent levels from 14 to 21 days old, and it was being stabilized on 45 days old. The bone mineral density was larger on the epiphyisis distal of birds that ingested filtered water doing these birds to resist a larger bone pressure in this area comparing to birds that ingested no filtered water. The medium values of serum calcium didn't present significant variations among the analyzed treatments. On the other hand, the serum levels of phosphorus of birds treated with filtered water were smaller in relation to the one that received water no filtered. On the scanning electron microscopy, it was observed that while the density of intestinal villi increased in birds that received no filtered water, the intestinal integrity was maintained in chickens treated with water filtered in response to their microbiological condition. In macroscopic analysis of the small intestine and of the kidneys, there wasn't difference among the treatments for length measures, width, absolute and relative weight of the organs. In the intestinal morphometry, it was observed that the length of the villi and the number of goblet cells didn't vary among the treatments. However, there was increase of small intestinal crypts depth in birds that received no filtered water, probably in function of the tax of intestinal turnover increase. Moreover, length intestinal villi were more significant in duodenum of birds that ingested water no filtered in relation to filtered water... (Complete abstract click electronic access below) / Doutor
196

Influência da associação de osso bovino mineral com osso alógeno fresco congelado em enxertos para levantamento de seio maxilar. Estudo clínico, histológico e histomorfométrico em humanos / Bovine bone mineral combined with fresh frozen allografts bone in sinus augmentation. Case series, histological and histomorphometrical in humans.

Sehn, Felipe Perraro 30 May 2014 (has links)
O osso alógeno fresco congelado e o Bio-Oss® (OBM) são materiais conhecidos como substitutos ao osso autógeno em cirurgias de levantamento de seio maxilar. O objetivo deste estudo foi avaliar clínica, histológica e histomorfometricamente o processo de reparo de enxertos alógenos com e sem a utilização de OBM, utilizados em técnicas de levantamento de seio maxilar em humanos. Neste estudo do tipo prospectivo, randomizado, tipo série de casos, comparativo, foram operados 34 seios maxilares de pacientes de ambos os sexos, que apresentavam um rebordo ósseo residual com altura máxima de 5 mm na região de seios maxilares para reconstrução em altura para cirurgias de levantamento de seio maxilar prévia à reabilitação por implantes. Os pacientes foram divididos em a) Grupo Controle: Dezessete (17) seios maxilares enxertados somente com a utilização de osso alógeno e b) Grupo Teste: 17 seios maxilares reabilitados com osso alógeno e OBM, na proporção de 2:1. Seis meses após a enxertia, no momento da instalação dos implantes, amostras ósseas foram coletadas por meio de trefinas para análise histológica e histomorfométrica. Os dados da investigação foram submetidos ao teste t de Student para amostras independentes empregado para comparações entre os dois grupos, Mann-Whitney e testes de correlação foram aplicados. 29 pacientes com uma média de idade de 51,32 anos (± 6,44), foram divididos em grupos controle (17) e teste (12), sendo 34 seios avaliados no total. Não houve diferença estatística entre os grupos com relação à idade (p = 0,23) e ao gênero (p = 0,56). Mediana do torque de inserção dos implantes foi de 32N para o grupo controle, e 45N para o grupo teste (p < 0,0001). Taxa de sucesso no grupo controle foi de 93,02% e 100% no grupo teste. Análise histológica apresentou no grupo controle osso alógeno residual com lacunas osteocíticas vazias e padrão lamelar; osso neoformado com lacunas osteocíticas com osteócitos viáveis e padrão imaturo; osteoblastos em íntimo contato matriz osteóide, formando pontes entre os blocos de osso alógeno e osso neoformado; osteoclastos em proximidade às áreas remodelação óssea; ausência de sinais de infiltrado inflamatório; tecido conjuntivo; e no grupo teste, todos os ítens acima e osso bovino mineral. Histomorfometria: material enxertado remanescente (p = 0,74); osso alógeno remanescente (35.78% ± 6.21% grupo controle, 19.72% ± 10.42% grupo teste; p < 0,0001); OBM remanescente no grupo teste (14,78% ± 8,67); osso neoformado (11.94% ± 1.71% grupo controle, 25.79% ± 8.76% grupo teste; p < 0,001); osso total (47.72% ± 5.6% grupo controle, 58.96% ± 8.1% grupo teste; p < 0,001); tecido conjuntivo (52.27% ± 5.6% grupo controle, 41.45% ± 8.4% grupo teste; p < 0,01). Adicionar OBM ao osso alógeno em cirurgias de levantamento de seio maxilar mostrou-se uma técnica de enxertia eficaz para a instalação de implantes. Resultou em maior torque de inserção, porcentagens maiores de osso neoformado e osso total, permitindo a instalação de implantes e reabilitação protética funcional. / Allograft fresh frozen bone and Bio-Oss are knows as autogenous bone materials substitutes in maxillary sinus lifting. The aim of this study was to evaluate clinical, histological and histomorphometrically the process of repair with and without the association of BBM in maxillary sinus augmentation. In this prospective, randomized, comparative case series study, 34 maxillary sinuses were augmented, which had a residual bone ridge with a maximum height of 5 mm in maxillary sinus reconstruction region at the time for surgery of maxillary sinus prior to rehabilitation by implants. Patients were divided into a) control group: seventeen (17) grafted maxillary sinuses with only allograft bone and b) test group: 17 maxillary sinuses rehabilitated with allograft bone and BBM in a 2:1 ratio. Six months after grafting, at time of implant placement, bone samples were collected using a trephine burr for histological and histomorphometrical analysis. The research data were subjected to Student\'s t test for independent samples used for comparisons between two groups, Mann - Whitney and correlation tests were applied. 29 patients with a mean age of 51.32 years (± 6.44), were divided into control group (17) and test (12), with 34 maxillary sinuses evaluated in total. There was no statistical difference between the groups regarding to age (p = 0.23) and gender (p = 0.56). Median insertion torque of the implants was 32N for the control group and 45N for the test group (p < 0.0001). Survival rate in the control group was 93.02% and 100% in the test group. Histological analysis showed, at the control group, residual allograft bone with empty osteocytic lacunae and lamellar pattern; newly formed bone with osteocytic lacunae with viable osteocytes and immature pattern; osteoblasts in close contact with osteoid matrix, forming bridges between the blocks of allograft bone and new bone formation; osteoclasts in bone remodeling surrounding areas; no evidence of inflammatory infiltrate; connective tissue; and in the test group, all the items above and bovine bone mineral. Histomorphometry: graft remaining material (p = 0.74); remaining allogenous bone (35.78% ± 06.21% control group, 19.72% ± 10:42% test group, p < 0.0001); BBM remaining in the test group (14.78% ± 8.67); newly formed bone (11.94% ± 1.71% control group, 25.79% ± 8.76% test group, p < 0.001); total bone (47.72% ± 5.6% control group, 58.96% ± 8.1% test group, p < 0.001); connective tissue (52.27% ± 5.6% control group, 41.45% ± 8.4% test group, p < 0.01). Adding bovine bone mineral to allogenous bone in maxillary sinus surgery proved to be an effective technique of grafting for implant placement. It resulted in higher insertion torque, higher percentages of new bone formation and total bone, allowing installation of implants and functional loading.
197

Uticaj modela programa vežbanja na koštanu gustinu i biohemijske markere koštanog remodelovanja kod žena u pre- i postmenopauzi / The effects of the model of exercise program onbone mineral density and biochemical markers of bone turnover in pre- and postmenopausal women

Marijanac Ana 24 September 2018 (has links)
<p>Generalni cilj ovog istraživanja je da se utvrdi da li postoji uticaj primenjenog<br />programa vežbanja na parametre ko&scaron;tane gustine i biohemijske markere ko&scaron;tanog<br />remodelovanja kod žena u periodu premenopauze i postmenopauze.<br />Uzorak ispitanica je činilo 26 žena starosti 45 do 55 godina, od kojih su 13 u periodu<br />premenopauze, a 13 u periodu postmenopauze. Ispitanice su učestvovale u programu vežbanja<br />u trajanju od 6 meseci, koji se realizovao u Novom Sadu, 4 puta nedeljno u trajanju od sat<br />vremena. Za utvrđivanje uticaja programa vežbanja na ko&scaron;tanu gustinu merena su 3<br />osteodenzitometrijska parametra na kičmi, vratu butne kosti i kuku i 5 parametara<br />biohemijskih markera ko&scaron;tanog remodelovanja.<br />Da bi se utvrdio uticaj vežbanja kod ispitanica, primenjena je multivarijatna analize<br />varijanse (MANOVA). Na celokupnom uzorku ispitanica nije utvrđena statistički značajna<br />razlika ni u jednom merenom parametru ko&scaron;tane gustine. U odnosu na biohemijske markere,<br />do&scaron;lo je do značajnog smanjenja nivoa ukupne alkalne fosfataze. Kod žena u periodu<br />premenopauze i kod žena u periodu postmenopauze, program vežbanja nije značajno uticao<br />na parametre ko&scaron;tane gustine merene na kičmi, vratu butne kosti i kuku (DXA, Lunar<br />Prodrigy), kao ni na parametre biohemijskih markera ko&scaron;tanog remodelovanja.<br />Primenom multivarijatne analize kovarijanse (MANCOVA) utvrđena je značajna<br />razlika u uticaju programa vežbanja između žena u pre- i postmenopauzi u mineralnoj<br />ko&scaron;tanoj gustini vrata butne kosti (BMD VF) i markera beta-crosslaps (CTX). Mineralna<br />ko&scaron;tana gustina je nakon programa vežbanja veća, a nivo beta-crosslapsa niži kod žena u<br />premenopauzi nego kod žena u periodu postmenopauze.<br />Na osnovu dobijenih rezultata, zaključujemo da je potreban duži vremenski period<br />realizacije programa vežbanja kako bi se mogla primetiti statistički značajna promena<br />merenih parametara. Ispitanicama se savetuje da nastave sa vežbanjem kako bi usporile<br />gubitak kosti</p> / <p>The genaral aim of this research is to determine is there an effects of the applied exercise<br />program on bone mineral density and and biochemical markers of bone turnover in the<br />premenopausal and postmenopausal period.<br />The sample was consisted of 26 women aged 45 to 55 years, of which 13 were in<br />premenopausal and 13 in postmenopausal period. Subjects were included (had performing) in 6-month<br />exercise program, which was implemented (maintained) in Novi Sad, 4 times a week in duration for an<br />hour. Three osteodensitometric parameters on lumbar spine, femoral neck and hip (DXA, Lunar<br />Prodrigy) and five parameters of biochemical markers of bone turnover were measured to assessed<br />(to determine) the effects of exercise program on bone density.<br />Multivariate analysis of variance (MANOVA) was used to determine the effect of exercise.<br />For the entire sample of subjects, there were no statistically significant difference in any measured<br />bone density parameter, but looking at biochemical markers, total alkaline phosphatase level were<br />significanly reduced. There were no significant changes in bone density parameters on the lumbar<br />spine, femoral neck and hip nor on the parameters of biochemical markers of bone turnover in women<br />in premenopausal and postmenopausal period.<br />Applying multivariate analyse of covariance it was found a significant difference in the<br />exercise program effect between pre- and postmenopausal women in bone mineral density of femoral<br />neck (BMD VF) and beta-crosslaps marker of turnover (CTX). Femoral neck BMD was higher, and<br />beta-crosslaps level was lower in premenopausal women than in postmenopausal women after<br />completion exercise program.<br />Based on obtained results, we conclude that is required a longer perod of exercise program<br />ralization in order to notice a statistically significant change in measured parameters. Subjects are<br />advised to continue their exercising in order to slow down the bone loss</p>
198

Bone Metabolism in Men

Gillberg, Peter January 2001 (has links)
<p>In this thesis, the importance of the growth hormone (GH)/insulin-like growth factor (IGF) system and sex steroids for male bone metabolism has been investigated, and the effects of continuous low dose GH replacement in GH deficient (GHD) adults. In a population-based sample of men, positive correlations were found between bone mineral density (BMD) and IGF-I, IGF-II, IGF binding protein (IGFBP)-3 and the testosterone/sex hormone binding globulin (SHBG) ratio. Serum IGFBP-3 and testosterone levels and weight accounted for 34% to 48% of the variation in BMD at different sites. Compared to healthy age matched controls, men with idiopathic osteoporosis had lower estradiol/SHBG ratio and higher SHBG levels. There were no differences between the groups in serum levels of IGF-I, IGFBP-3, 24 hour cumulated GH secretion or peak GH secretion. In the patients, there was a positive correlation between the estradiol/SHBG ratio and BMD in femoral neck. Treatment of patients and controls with GH 0.8 mg/day for one week resulted in similar increases in serum markers for bone turnover in both groups. Several positive correlations between indices of GH secretion and markers for bone turnover were found in the patients. Men with idiopathic osteoporosis were treated with GH, continuously (0.4 mg/day) or intermittently (0.8 mg/day for two weeks every third month), for two years followed by one year of follow-up. After two years, the BMD and bone mineral content in lumbar spine and total body and serum osteocalcin levels were increased in both groups. This increase was sustained one year post treatment. Treatment of GHD adults with a low fixed dose of GH (0.17 mg/day) for three months, resulted in increases in serum IGF-I and IGFBP-3 levels and lean body mass, and a reduction in fat mass and total and low-density lipoprotein cholesterol levels. These beneficial effects were accomplished without serious side effects. These findings indicate that: i) the sex hormone and GH/IGF systems are important in male bone metabolism, ii) a combination of subtle disturbances in these two systems could contribute to the development of male idiopathic osteoporosis, iii) GH treatment could be considered as a treatment option in this condition.</p>
199

Osteoporosis in chronic liver disease

Ormarsdóttir, Sif January 2001 (has links)
<p>Ormarsdóttir, S. 2001. Osteoporosis in Chronic Liver Disease. Acta Universitatis Upsaliensis. <i>Comprehensive Summaries of Uppsala Dissertations from the Faculty of Medicine</i> 1037. 60 pp. Uppsala. ISBN 91-554-5021-0. </p><p>Osteoporosis is a well-known and frequently reported complication of chronic liver disease (CLD) with a high fracture rate contributing to significant morbidity after liver transplantation. The pathogenesis is unknown and controversy exists about many risk factors for osteoporosis in CLD. </p><p>In the present thesis, bone mineral density (BMD) was found to be significantly lower at the lumbar spine (<i>p</i><0.01) in a cohort of patients with CLD compared with age- and gender -matched individuals. Osteoporosis was found in 30% of the patients and 15% of the controls, respectively. Low body mass index (BMI), corticosteroid treatment, prothrombin time, age and female gender were independent risk factors for osteoporosis in the patients. </p><p>In a follow-up study, 43 of 72 patients were available for a second BMD measurement 25 months (median) after the first. Bone loss at the femoral neck was 1.5 ± 2.4% in females and 2.9 ± 2.0% in males with a significant decrease in BMD Z-score over time (<i>p</i>=0.005 and <i>p</i>=0.02 for females and males, respectively), indicating increased bone loss at this site. Hyperbilirubinaemia and low circulating levels of 25-hydroxy vitamin D<sub>3</sub> predicted increased bone loss at the femoral neck. These findings suggest that cortical bone, in addition to trabecular bone, may be affected in CLD and bilirubin and vitamin D<sub>3</sub> may be involved in the pathophysiology of osteoporosis in CLD. </p><p>In order to elucidate the suggested role of insulin-like growth factors (IGFs) and leptin in the pathophysiology of osteoporosis in CLD, we studied the relationship between these factors and BMD. Levels of IGFs were extremely low (<i>p</i><0.0001 compared with the controls) and related to liver function but no correlation was found between the IGFs and BMD. Serum leptin adjusted for BMI correlated negatively with BMD in female patients (<i>p</i>=0.003 and <i>p</i>=0.04 at the lumbar spine and the femoral neck, respectively) and in male patients at the femoral neck (<i>p</i>=0.04). Thus, the IGFs appear not to be involved in the pathophysiology of osteoporosis in CLD but a role of circulating leptin is possible. </p>
200

Osteoporosis in chronic liver disease

Ormarsdóttir, Sif January 2001 (has links)
Ormarsdóttir, S. 2001. Osteoporosis in Chronic Liver Disease. Acta Universitatis Upsaliensis. Comprehensive Summaries of Uppsala Dissertations from the Faculty of Medicine 1037. 60 pp. Uppsala. ISBN 91-554-5021-0. Osteoporosis is a well-known and frequently reported complication of chronic liver disease (CLD) with a high fracture rate contributing to significant morbidity after liver transplantation. The pathogenesis is unknown and controversy exists about many risk factors for osteoporosis in CLD. In the present thesis, bone mineral density (BMD) was found to be significantly lower at the lumbar spine (p&lt;0.01) in a cohort of patients with CLD compared with age- and gender -matched individuals. Osteoporosis was found in 30% of the patients and 15% of the controls, respectively. Low body mass index (BMI), corticosteroid treatment, prothrombin time, age and female gender were independent risk factors for osteoporosis in the patients. In a follow-up study, 43 of 72 patients were available for a second BMD measurement 25 months (median) after the first. Bone loss at the femoral neck was 1.5 ± 2.4% in females and 2.9 ± 2.0% in males with a significant decrease in BMD Z-score over time (p=0.005 and p=0.02 for females and males, respectively), indicating increased bone loss at this site. Hyperbilirubinaemia and low circulating levels of 25-hydroxy vitamin D3 predicted increased bone loss at the femoral neck. These findings suggest that cortical bone, in addition to trabecular bone, may be affected in CLD and bilirubin and vitamin D3 may be involved in the pathophysiology of osteoporosis in CLD. In order to elucidate the suggested role of insulin-like growth factors (IGFs) and leptin in the pathophysiology of osteoporosis in CLD, we studied the relationship between these factors and BMD. Levels of IGFs were extremely low (p&lt;0.0001 compared with the controls) and related to liver function but no correlation was found between the IGFs and BMD. Serum leptin adjusted for BMI correlated negatively with BMD in female patients (p=0.003 and p=0.04 at the lumbar spine and the femoral neck, respectively) and in male patients at the femoral neck (p=0.04). Thus, the IGFs appear not to be involved in the pathophysiology of osteoporosis in CLD but a role of circulating leptin is possible.

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