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Osteoporose nach Lebertransplantation:Gewicht von Lebergrunderkrankung, Anabolen Sexualhormonen, Immunsuppression sowie Therapie mit Calcitriol als Monotherapeutikum und in Kombination mit Kalzium und NatriumfluoridKubo, Andreas 14 January 2000 (has links)
Die sekundäre Osteoporose ist eine der häufigsten mit der Lebertransplantation verbundenen Komplikationen. Sie ist mit spezifischen chronischen Lebererkrankungen assoziiert und manifestiert sich in ihrem ausgeprägtesten Stadium in Form von Frakturen nicht selten nach der Lebertransplantation (LTX). Management und Therapie der Osteoporose stellen noch heute ein wesentliches Problem bei Lebertransplantatempfängern dar. Das erste Ziel dieser Studie bestand in der Erfassung der Bedeutsamkeit verschiedener spezifischer Lebererkrankungen, des Einflusses von anabolen Sexualhormonen und Immunosuppression auf den Knochensubstanzverlust bei Patienten mit LTX. Das zweite Ziel dieser Studie bestand in der Abschätzung des therapeutischen Effektes von Calcitriol (1,25 (OH)2D3) in niedrigen Dosierungen zu 0,25 µg und 0,5 µg als Monotherapeutikum oder in Kombination mit 1000 mg Kalzium (Ca) bei leichter oder mäßiger Osteoporose. Patienten mit schwerer Osteoporose wurden mit einer Dreifachkombination bestehend aus 0,5 µg Calcitriol, 1000 mg Ca und 25 mg Natriumfluorid behandelt. Von 860 Patienten, die sich im Zeitraum von 1988 bis 1996 einer Lebertransplantation unterzogen, wurden insgesamt 509 Patienten (256 Männer, 213 Frauen) 5 Therapiegruppen und einer Kontrollgruppe zugeteilt. Der Mineralstatus des Knochens und der therapeutische Effekt wurden mittels vor LTX und danach halbjährlich erfolgten Knochendichtemessungen (Dual Energy X-ray Absorptiometry - DEXA) an der Lendenwirbelsäule (LWS) sowie am Schenkelhals (SH) bewertet. Patienten mit primärer biliärer Zirrhose, primär sklerosierender Cholangitis und autoimmuner Zirrhose weisen präoperativ und innerhalb der ersten 6 postoperativen Monate den niedrigsten Knochenmineralbestand auf. Den Sexualhormonstatus betrachtend wiesen 17,5% aller gemessenen Testosteronserumspiegel bei Männern und 78,3% aller gemessenen Serumöstrogenspiegel bei postmenopausalen Frauen hypogonadische Werte auf. Jedoch waren die Serumtestosteronkonzentrationen bei Männern und die Serumöstrogenkonzentrationen bei postmenopausalen Frauen zwischen den mit Calcitriol therapierten Patienten und nichttherapierten Patienten (Kontrollgruppe) nicht signifikant verschieden. Die Basisimmunsuppression bestand aus Cyclosporin A und Tacrolimus kombiniert mit Prednisolon. Bei Patienten, die Tacrolimus erhielten war der Knochenverlust an der LWS signifikant geringer (p=0,0249). Diese Beobachtung wurde höchstwahrscheinlich durch deutlich erhöhte Prednisolongaben bei Patienten mit Cyclosporin A bedingt. Mit Calcitriol therapierte Patienten erhielten wesentlich mehr Prednisolon bezogen auf die kumulative Menge und den Zeitraum im Vergleich zur nichttherapierten Kontrollgruppe. Während die niedrige Dosierung von 0,25 mg zusätzlich Kalzium benötigte um bessere Resultate am SH zu erzielen, führte die Dosierung von 0,5 µg zu einem Knochendichtezuwachs von 10,17% an der LWS und 5,9% am SH ohne Kalziumzusatz und zu einem Knochendichtezuwachs von 10,0% an der LWS und 5,2% am SH mit Kalziumgabe in einem durschnittlichen Therapiezeitraum von 1,5 Jahren. Die Dreifachkombination aus 0,5 µg Calcitriol, 1000 mg Ca und 25 mg Natriumfluorid zeigte bei Patienten mit schwerwiegender Osteoporose die besten Resultate an der LWS (Zuwachsrate 10,67%) und am SH (Zuwachsrate 12,97%) nach 1,15 Jahren. Bei nichttherapierten Patienten der Kontrollgruppe wurde ein Spontanzuwachs der Knochendichte an der LWS von 2,25% und ein Knochendichteabfall am SH von 0,86% beobachtet. Die Rate atraumatischer Frakturen konnte mit 1,77% gering gehalten werden. Calcitriol ist ein wirkungsvolles, nebenwirkungsarmes Therapeutikum zum Ausgleich und zur Prävention des Knochenmasseverlustes bei Patienten mit Lebertransplantation. Natriumfluorid steigert den Mineralisationseffekt besonders am Schenkelhals. / Secondary osteoporosis is a frequent complication of endstage liver disease which often detoriates after orthotopic liver transplantation (OLT). Management and therapy of osteopenic bone disease are still a major problem in liver transplant recipients. First purpose of this study was to estimate the magnitude of various specific liver diseases, sexual hormones and immunosuppression on bone loss in patients undergoing OLT. The second aim was to evaluate the effect of calcitriol (1,25(OH)2D3) in comparatively low dosages of 0,25 µg and 0,5 µg as a single therapy or in combination with 1000 mg calcium (Ca) in light and moderate osteoporosis. Patients with severe osteoporosis received a triple combination with 0,5 µg calcitriol, 1000 mg Ca and 25 mg sodium fluoride. Out of 860 patients undergoing OLT from 1988 to 1996, 509 (256 males, 213 females) were assigned to 5 treatment groups as well as to a control group. Bone mineral status and the effect of therapy were estimated by bone mineral density (BMD) measurements with dual energy X-ray absorptiometry of lumbar spine (LS) and femoral neck (FN) before and every six month after OLT. Primary biliary cirrhosis, primary sclerosing cholangitis and autoimmune cirrhosis were associated with a low pre-existing bone mineralisation and most severe decrease of bone mass during the early post-transplantation period. Considering hormonal measuring performed during the study period 17,5% of all measured testosterone levels in men and 78,3% of all measured oestrogen levels in postmenopausal women were in hypogonadic range. Testosterone and oestrogen levels were not significant different among with calcitriol treated and non-treated patients. Baseline immunosuppression consisted of cyclosprin A or tacrolimus initially combined with corticosteroids. Patients treated with tacrolimus had significant less bone mass reduction in the lumbar spine than patients treated with cyclosporine (p=0,0249). This observation was certainly caused by less application of prednisolone. With calcitriol treated patients received considerably more prednisolone and over a longer period of time than non-treated controls. Bone mineralisation essentially increased under calcitriol therapy in all treatment groups. Whereas the low dose of 0,25 µg needed a complementation of Ca especially to achieve better results in the FN, the dosage of 0,5 µg led to BMD improvement of 10,17% in LS and 5,9% in FN without Ca and to an improvement of 10,0 % in LS and 5,2% in FN with Ca supplementation in an average period of 1,5 years. The triple combination with 0,5 µg calcitriol, 1000 mg Ca and 25 mg sodium fluoride which was used in cases of severe osteoporosis showed the best results with a BMD augmentation rate of 10,67% in LS and 12,79% in FN after a period of 1,15 years. In the untreated controls we only found spontaneous BMD improvement of 2,25% in LS and a further bone loss of 0,86% in FN. A small fracture rate of 1,77% was observed. Calcitriol therapy effectively prevents posttransplant bone loss and augments bone mineralisation in osteoporotic patients. Moreover it minimizes the incidence of atraumatic fractures. Additional sodium fluoride increases the bone density in LS and has a special effect on FN. Side effects are negligible.
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The evaluation of bone strengthJain, Atul January 2008 (has links)
Bone drilling is a major part of orthopaedic surgery performed during the internal fixation of fractured bones. At present, information related to drilling force, drilling torque, rate of drill bit penetration and drill bit rotational speed is not available to orthopaedic surgeons, clinicians and researchers as bone drilling is performed manually. This research demonstrates that bone drilling force data if recorded in-vivo, during the repair of bone fractures, can provide information about the strength/quality of the bone. Drilling force does not give a direct measure of bone strength; therefore it has been correlated with the shear strength and screw pullout strength to determine the efficacy in estimating the bone strength. Various synthetic bone material densities and animal bones have been tested to demonstrate the use of drilling force data. A novel automated experimental test rig, which enables drilling tests, screw insertion and screw pullout tests to be carried out in a controlled environment, has been developed. Both drilling and screw pullout tests have been carried out in a single setting of the specimen to reduce the experimental errors and increase repeatability of the results. A significantly high value of correlation (r² > 0.99) between drilling force & shear strength and also between drilling force & normalised screw pullout strength in synthetic bone material was found. Furthermore, a high value of correlation (r² = 0.958 for pig bones and r² = 0.901 for lamb bones) between maximum drilling force & normalised screw pullout strength was also found. The result shows that drilling data can be used to predict material strength. Bone screws are extensively used during the internal fixation of fractured bones. The amount of screw been tightened is one of the main factor which affects the bone-screw fixation quality. Over tightening of screw can result into the loss of bone-screw fixation strength, whereas under tightening can result in the screw loosening. Therefore, optimum tightening of the screw is important to achieve the maximum bone-screw fixation strength. At present, optimum tightening of the screw is entirely dependent upon the skill and judgment of the surgeon, which is predominantly based on the feel of the screw tightening torque. Various studies have been reported in the literature to develop an algorithm to set an optimum tightening torque value to be used in surgery. A method which is based on the use of rotation angle of the screw while tightening, rather than using screw insertion/tightening torque, to optimise the bone-screw fixation strength is proposed in this research. The effectiveness of the proposed method has been successfully demonstrated on the synthetic bone material using the designed test rig. The optimum angle for the tested screw was found to be 120° which is equivalent to 33% of the screw pitch.
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Využití vibrací ve sportu a zdravotnictví / Use of vibration in sports and health careKoutná, Martina January 2012 (has links)
Title: The Use of Vibration in Sports and Health Care Objectives: The aim of this study is to confirm or refute established hypotheses. Hypotheses: 1. The use of vibration loading improves muscle strength. 2. The use of vibration loading improves bone mineral density. 3. The use of vibration loading can influence balance. Methods: This diploma thesis is elaborated as search form. It is based on exploration of available literary sources, clinical trials accessible through electronic databases of medical and sports, and library catalogs. The resources from sport, physiology, biomechanics, and various medical disciplines (osteology, physiotherapy, kinesiology) were used also. Results: Due to retrieval process of whole body vibration training it was found out that this method can improve muscle strength, bone mineral density, balance and mobility. The effect depends on chosen parameters of whole-body vibrations. Under certain conditions whole-body vibration training could represent an alternative or a supplement to conventional training in order to increase muscle strength and bone mineral density or improve balance and mobility of elderly. The selection of right vibration parameters could support ordinary physical therapy of some neurological disorders. Keywords: vibration, whole-body vibration...
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Využití vibrací ve sportu a zdravotnictví / The Use of Vibration in Sports and Health CareKoutná, Martina January 2011 (has links)
Title: The Use of Vibration in Sports and Health Care Objectives: The aim of this study is to determine whole-body vibration training as potential training method in sport and health area. The usage of vibration training should increase strength, bone mineral density, and balance. Methods: This diploma thesis is solely theoretical. It is based on review of available literary sources, clinical trials accessible through electronic databases of medical and sports, and library catalogs. The resources from sport, physiology, biomechanics, and various medical disciplines (osteology, physiotherapy, kinesiology) were used also. Results: The research concluded that the usage of whole-body vibration of an appropriate frequency or acceleration respectively could represent an alternative or a supplement to conventional training in order to increase muscle strength and bone mineral density or improve balance and mobility of elderly. The selection of right vibration parameters could support ordinary physical therapy of some neurological disorders. Keywords: vibration, whole-body vibration training, muscle strength, balance, bone mineral density, neurological disorders, physical therapy
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Évaluation de la microarchitecture trabéculaire et des propriétés mécaniques osseuses in vivo chez l’humain par scanner périphérique a haute résolution : application clinique à l’ostéoporose / In vivo assessment of trabecular microarchitecture and bone biomechanical properties by high resolution peripheral quantitative tomography : application to osteoporosisVilayphiou, Nicolas 16 December 2010 (has links)
La microarchitecture osseuse est un des déterminants de la qualité osseuse qui peut maintenant être évaluée in vivo au radius et au tibia distaux avec une résolution isotropique de 82μm par un nouveau scanner à haute résolution (XtremeCT, SCANCO Medical AG). Par ailleurs, l’utilisation d’analyse en éléments finis sur les volumes 3D obtenus permet d’évaluer les propriétés biomécaniques de l’os comme la résistance osseuse. Nous avons montré qu’il s’agissait d’une technique prometteuse pour évaluer la densité, la microarchitecture et les propriétés biomécaniques osseuses au niveau des sites périphériques, notamment parce que ces mesures étaient associées chez la femme avec des fractures ostéoporotiques de toutes sortes. Nous avons également montré que les mêmes mesures étaient tout aussi pertinentes chez l’homme, alors qu’il est moins sujet à l’ostéoporose. Les résultats étaient associés aux fractures ostéoporotiques de toutes sortes, notamment les fractures vertébrales. L’analyse en éléments finis permet donc la mesure in vivo de la résistance osseuse, ce qui pourrait fournir des informations sur la fragilité osseuse et le risque de fracture non accessible par les seules mesures de densité ou de microarchitecture osseuse. / Bone microarchitecture is one of the determinants of bone quality that can now be evaluated in vivo at the distal radius and tibia with an isotropic resolution of 82μm with a new high-resolution peripheral scanner (XtremeCT, SCANCO Medical AG). Moreover, the use of finite element analysis on the 3D bone volume acquired allows the assessment of bone biomechanical properties such as bone strength. Our studies show that this technique is promising to assess bone density, microarchitecture and strength at peripheral skeletal sites. Indeed those measures were associated with osteoporotic fractures of all kinds in women. We also demonstrated that those same measures were associated with osteoporotic fractures of all kinds, including vertebral fractures, in men, who are less prone to be affected by osteoporosis. Finite element analysis allows in vivo measurement of bone strength, which might provide additional information about bone fragility and fracture risk that are not assessed by measures of density or microarchitecture.
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Effets de la greffe pulmonaire sur la densité minérale osseuse et l’anthropométrie des individus atteints de fibrose kystiqueDurette, Gabrielle 12 1900 (has links)
No description available.
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Calcificação prematura de artérias coronárias no lúpus eritematoso sistêmico: associação com duração de doença e densidade mineral óssea / Premature coronary artery calcification is associated with disease duration and bone mineral density in young female systemic lupus erythematosusRibeiro, Giovana Gomes 13 March 2009 (has links)
Objetivo: Avaliar a relevância de fatores de risco tradicionais para doença cardiovascular (FRC), fatores relacionados ao lúpus e densidade mineral óssea (DMO) na calcificação prematura de artérias coronárias (CAC) em mulheres jovens com lúpus eritematoso sistêmico (LES). Métodos: Noventa e quatro pacientes lúpicas do sexo feminino com duração de doença 5 anos e idade menor que 45 anos foram selecionadas consecutivamente para este estudo. Os fatores de risco cardiovascular analisados foram: diabetes mellitus, hipertensão arterial sistêmica, dislipoproteinemia, fumo, índice de massa corpórea (IMC), insuficiência ovariana e renal. Fatores de risco relacionados ao LES estudados foram: duração de doença, critérios ACR, SLICC/ACR modificado (excluindo escores relacionados à aterosclerose), SLEDAI, tratamento com glicocorticóide e ciclofosfamida. A densidade mineral óssea de corpo inteiro, coluna lombar e colo do fêmur foram realizadas por densitometria de dupla emissão de fontes de raios-X (DXA). Calcificação de artérias coronárias foi determinada usando tomografia computadorizada com 16 multidetectores. Resultados: Calcificação prematura de artérias coronárias foi identificada em 12 (12,7%) dos pacientes, havendo associação com maior freqüência de pacientes com FRC (p=0,008), maior número de FCR (p=0,003), idade (p=0,025), duração de doença (p=0,011) e SLICC (p=0,011). A análise individual dos FRC demonstrou que a presença de menopausa (p=0,036), dislipidemia (p=0,003) e hipertensão (p=0,006) foram significativamente associados com calcificação coronariana. Análise de regressão logística múltipla usando FRC, idade, duração de doença, SLICC e DMO de corpo inteiro revelou que apenas duração de doença (p=0,042) e DMO de corpo inteiro (p=0,023) permaneceram fatores significantes para calcificação coronariana. Conclusão: Identificamos que duração de doença e DMO reduzida são preditores independentes para calcificação coronariana prematura em mulheres jovens com LES, sugerindo um mecanismo subjacente comum / Objective: To evaluate the relevance of traditional cardiovascular risk factors (CVR), disease-related risk factors and bone mineral density (BMD) for premature coronary artery calcification (CAC) in young female systemic lupus erythematosus (SLE). Methods: Ninety-four female SLE patients 5 years disease duration and age <45 years were consecutively selected for this study. Cardiovascular risks (CVR) analyzed were: diabetes mellitus, arterial hypertension, dyslipoproteinemia, smoking, body mass index (BMI), ovarian and renal insufficiency. SLE-related risk factors evaluated were: disease duration, ACR criteria, modified SLICC/ACR (excluding atherosclerosis-related scores), SLEDAI, glucocorticoid and cyclophosphamide treatment. Bone mineral density (BMD) in whole body, lumbar spine and femoral neck was assessed by dual X ray absorptiometry (DXA). Coronary artery calcification was determined using the 16-slice multidetector computed tomography. Results: Premature coronary artery calcification was identified in 12 (12.7%) patients and was associated with a higher frequency of patients with CVR (p=0.008), a higher mean number of CVR (p=0.003), mean age (p= 0.025), mean disease duration (p=0.011) and mean SLICC (p=0.011). Individual analysis of CVR demonstrated that the presence of menopause (p= 0.036), dyslipidemia (p= 0.003) and hypertension (p=0.006) were significantly associated with coronary calcification. Additionally, premature calcification was associated with a lower whole body BMD (p=0.013). Multiple logistic regression analysis using CVR, age, disease duration, SLICC and whole body BMD revealed that only disease duration (p=0.042) and whole body BMD (p=0.023) remained significant factors for coronary calcification. Conclusion: We have identified that disease duration and decreased BMD are independent predictors for premature coronary calcification in young women with SLE, suggesting a common underlying mechanism
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Consommation chronique d'alcool, exercice physique et tissu osseux : modifications densitométriques, architecturales, biomécaniques et métaboliques chez le rat / Chronic alcohol consumption, physical exercise and bone tissue : densitometric, microarchitectural, biomechanic and metabolic changes in the ratMaurel, Delphine 24 November 2011 (has links)
La consommation d’alcool a des effets sur le tissu osseux. L’alcoolisme est une des causes d’ostéoporose secondaire chez l’homme. Dans ce travail nous avons mené différentes expérimentations chez le rat afin d’étudier les effets d’une consommation chronique d’alcool combinée ou non à un entraînement aérobie sur le tissu osseux. Nous avons montré qu’une faible dose d’alcool administrée pendant une période courte peut avoir un effet positif sur la densité minérale osseuse et l’épaisseur trabéculaire. En revanche, la combinaison activité physique et consommation modérée d’alcool n’a pas d’effet additif sur la potentialisation du tissu osseux. Nous avons également démontré un effet dose de l’alcool indiquant des effets délétères majorés sur la densité minérale osseuse (DMO), la microarchitecture corticale et la résistance osseuse avec des apports croissants (25%, 30% et 35% v/v). La modification de DMO s’accompagne d’un changement de composition corporelle et d’une diminution de la leptine systémique. Cependant, le nombre d’adipocytes augmente dans la moelle osseuse. Nous avons mis en évidence dans ce modèle d’ostéoporose secondaire due à l’alcool une augmentation de l’apoptose des ostéocytes, corrélée à la diminution de la DMO et à l’augmentation de l’adiposité médullaire. Nous avons de plus mis en évidence une incorporation de lipides dans les ostéocytes, incorporation fortement corrélée à l’apoptose de ces cellules. Enfin, nos résultats montrent qu’un exercice physique régulier combiné à une consommation chronique et excessive d’alcool permet de prévenir les effets délétères de l’alcool sur les paramètres osseux (porosité corticale, épaisseur corticale) et limite la diminution de la DMO. Cette diminution est associée à une régulation de l’apoptose des ostéocytes. / Heavy chronic alcohol consumption has deleterious effects on bone tissue. It is one of the major causes of secondary osteoporosis in men. In this work, we draw several experimentations to assess the effects of chronic alcohol consumption on bone, combined or not to an aerobic training in the rat. We showed that light to moderate chronic alcohol consumption during a short time lead to an increase of bone mineral density (BMD) and trabecular thickness, whith no additive effects of physical exercise on bone tissue. When the alcohol doses were increased, we showed deleterious effects on BMD, microarchitecture, bone resistance with a dose effect with increasing alcohol doses (25%, 30% and 35% v/v): the more alcohol was concentrated and the more the bone parameters were decreased. The BMD decrease was associated with a change in body composition, and with a decrease in serum leptin. However, the number of lipid droplets in the bone marrow was increased dramatically. We demonstrated that there was a huge increase in osteocyte apoptosis with alcohol (35% v/v) in this alcohol-induced osteoporosis model, which was correlated with BMD and bone marrow adiposity. We have also shown that there was lipid incorporation in bone micro vessels and in osteocytes, which was correlated with osteocyte apoptosis. Lastly, we showed that when regular exercise was associated with heavy chronic alcohol consumption, the bone parameters were normal (trabecular, cortical thickness, femur length) and the BMD was less decreased compared to alcohol-fed and sedentary rats. These effects were associated with a regulation of osteocyte apoptosis.
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Correlação entre Densidade Radiográfica - DR e Absorciometria por Raios-X de Duas Energias - DXA: Estudo “in vitro” / Correlation between Radiographic Density - RD and Dual-energy X-ray Absorptiometry - DXA "in vitro" studyFernandes, Rodrigo Antonio 18 January 2019 (has links)
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Previous issue date: 2019-01-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo desse estudo foi inferir a Densidade Mineral óssea (DMO) a partir da imagem radiográfica (Raios-X) usando como referência a DMO de uma escada de alumínio mensurada por Absorciometria por de Duas-Energias (DXA). Para isso foram utilizadas 30 amostras de tecido ósseo cortical e 30 amostras de tecido ósseo trabecular de osso bovino “in vitro”. Foram mensurados neste estudo a Densidade Mineral Óssea (DMO), o Conteúdo Mineral Ósseo (CMO) ambos obtidos pelo densitômetro LUNAR®–DPX ALPHA; a Quantidade Mineral Óssea (QMO) massa das cinzas após a calcinação das amostras; a densidade real das amostras (dReal=massa/volume). Foram feitas 10 tomadas de RX com as 60 amostras, entremeadas pela escada de alumínio (referencial densitométrico). A correlação entre as técnicas (DR-tons de cinza e DXA g/cm2) gerou equações de regressão para cada uma das dez radiografias e permitiu inferir a densidade mineral óssea (DMODR), obtida através da conversão dos tons de cinza em densidade radiográfica pelo software ImageJ® para cada uma das 10 tomadas radiográficas; calculou-se então a média da densidade mineral óssea calculada pela densitometria radiográfica (XDMODR) de todas as dez radiografias. Foi observado que a média da densidade real das amostras foi de 2,2±0,23g/cm2 e 1,05±0,09g/cm2 enquanto que a média da densidade mensurada pelo DXA foi de 0,73±0,11g/cm2 e 0,22±0,11g/cm2, observou que a media da DMODR ficou em 0,93±0,11g/cm2 e 0,34±0,14 g/cm2 para o osso cortical e trabecular respectivamente. A média da CMO foi de 0,19±0,9g e 0,08±0,02g e a media da QMO 0,14±0,04g e 0,05±0,03g para o osso cortical e trabecular respectivamente. Foi possível obter bons coeficientes de determinação entre todas as variáveis estudadas: CMO e QMO, R2 =0,747; DMO e dReal com R2 = 0,765; dReal e DMODR; DMO e XDMODR, respectivamente 0,764 e 0,856. Para as correlações foram usadas amostras de dois tecidos ósseos cortical e trabecular, o que sugere distinção entre as amostras com as metodologias utilizadas / The aim of this study was to infer the bone mineral density (BMD) from the radiographic image (X-X) with reference to the BMD of an aluminum step wedge measured by absorptiometry Dual-energy (DXA). For this we used 30 samples of cortical bone 30 and cancellous bone tissue samples of bovine bone "in vitro". Were measured in this study Bone Mineral Density (BMD), bone mineral content (BMC) both obtained by densitometer LUNAR® DPX-ALPHA; Volume Bone Mineral (QMO) mass of ash after calcination of the samples; the real density of the samples (dReal = mass / volume). 10 taken RX were made with the samples 60, interspersed by aluminum step wedge (densitometric reference). The correlation between the techniques (gray DR-tones and DXA g / cm 2) generated regression equations for each of the ten X-rays and allowed to infer bone mineral density (DMODR) obtained by converting grayscale radiographic density by ImageJ® for each of the 10 radiographic taken. It was then calculated average bone mineral density calculated by X-ray densitometry (XDMODR) radiographs of all ten. Was observed that the average true density of the samples was 2.2±0.23g/cm2 and 1.05±0.09g/cm2 while the average density measured by DXA was 0.73±0.11g/cm2 and 0.22±0.11g/cm2 interesting that the average DMODR was 0.93±0.11g/cm2 and 0.34±0.14g/cm2 for cortical and cancellous bone respectively. The average of the BMC was 0.19±0.08g and 0.9±0.02g, and the average QMO 0.14±0.04g and 0.05±0 03g for cortical and cancellous bone respectively. It was possible to obtain good determination coefficients between all variables: BMC and QMO, R2 = 0.747; BMD and dReal with R2 = 0.765; dReal and DMODR; BMD and XDMODR respectively 0.764 and 0.856. For correlations were used two samples of cortical and cancellous bone tissues, suggesting a difference between the samples with the methodologies used.
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Calcificação prematura de artérias coronárias no lúpus eritematoso sistêmico: associação com duração de doença e densidade mineral óssea / Premature coronary artery calcification is associated with disease duration and bone mineral density in young female systemic lupus erythematosusGiovana Gomes Ribeiro 13 March 2009 (has links)
Objetivo: Avaliar a relevância de fatores de risco tradicionais para doença cardiovascular (FRC), fatores relacionados ao lúpus e densidade mineral óssea (DMO) na calcificação prematura de artérias coronárias (CAC) em mulheres jovens com lúpus eritematoso sistêmico (LES). Métodos: Noventa e quatro pacientes lúpicas do sexo feminino com duração de doença 5 anos e idade menor que 45 anos foram selecionadas consecutivamente para este estudo. Os fatores de risco cardiovascular analisados foram: diabetes mellitus, hipertensão arterial sistêmica, dislipoproteinemia, fumo, índice de massa corpórea (IMC), insuficiência ovariana e renal. Fatores de risco relacionados ao LES estudados foram: duração de doença, critérios ACR, SLICC/ACR modificado (excluindo escores relacionados à aterosclerose), SLEDAI, tratamento com glicocorticóide e ciclofosfamida. A densidade mineral óssea de corpo inteiro, coluna lombar e colo do fêmur foram realizadas por densitometria de dupla emissão de fontes de raios-X (DXA). Calcificação de artérias coronárias foi determinada usando tomografia computadorizada com 16 multidetectores. Resultados: Calcificação prematura de artérias coronárias foi identificada em 12 (12,7%) dos pacientes, havendo associação com maior freqüência de pacientes com FRC (p=0,008), maior número de FCR (p=0,003), idade (p=0,025), duração de doença (p=0,011) e SLICC (p=0,011). A análise individual dos FRC demonstrou que a presença de menopausa (p=0,036), dislipidemia (p=0,003) e hipertensão (p=0,006) foram significativamente associados com calcificação coronariana. Análise de regressão logística múltipla usando FRC, idade, duração de doença, SLICC e DMO de corpo inteiro revelou que apenas duração de doença (p=0,042) e DMO de corpo inteiro (p=0,023) permaneceram fatores significantes para calcificação coronariana. Conclusão: Identificamos que duração de doença e DMO reduzida são preditores independentes para calcificação coronariana prematura em mulheres jovens com LES, sugerindo um mecanismo subjacente comum / Objective: To evaluate the relevance of traditional cardiovascular risk factors (CVR), disease-related risk factors and bone mineral density (BMD) for premature coronary artery calcification (CAC) in young female systemic lupus erythematosus (SLE). Methods: Ninety-four female SLE patients 5 years disease duration and age <45 years were consecutively selected for this study. Cardiovascular risks (CVR) analyzed were: diabetes mellitus, arterial hypertension, dyslipoproteinemia, smoking, body mass index (BMI), ovarian and renal insufficiency. SLE-related risk factors evaluated were: disease duration, ACR criteria, modified SLICC/ACR (excluding atherosclerosis-related scores), SLEDAI, glucocorticoid and cyclophosphamide treatment. Bone mineral density (BMD) in whole body, lumbar spine and femoral neck was assessed by dual X ray absorptiometry (DXA). Coronary artery calcification was determined using the 16-slice multidetector computed tomography. Results: Premature coronary artery calcification was identified in 12 (12.7%) patients and was associated with a higher frequency of patients with CVR (p=0.008), a higher mean number of CVR (p=0.003), mean age (p= 0.025), mean disease duration (p=0.011) and mean SLICC (p=0.011). Individual analysis of CVR demonstrated that the presence of menopause (p= 0.036), dyslipidemia (p= 0.003) and hypertension (p=0.006) were significantly associated with coronary calcification. Additionally, premature calcification was associated with a lower whole body BMD (p=0.013). Multiple logistic regression analysis using CVR, age, disease duration, SLICC and whole body BMD revealed that only disease duration (p=0.042) and whole body BMD (p=0.023) remained significant factors for coronary calcification. Conclusion: We have identified that disease duration and decreased BMD are independent predictors for premature coronary calcification in young women with SLE, suggesting a common underlying mechanism
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