Human femur assessment using isotropic and orthotropic materials dependent of bone density

The bone mass reduction and the deterioration of the tissue micron-architecture lead to a bigger fragility of the bone and to the consequent increase of the fracture risk. For this fact, it is considered excellent the quantification of the mass density and the verification of its influence in the bone resistance assessment. The apparent density is defined as the density without fluid influence, being the effective density at that includes the marrow mass, essentially fluid. This measurement is made through the use of a gray scale values on the medical image in study. The values in Hounsfield units are determined, being this scale later converted into measure of the bone density. With this measure an exponential relation will be used allowing calculate the biomechanics properties dependence for cortical and trabecular bone. With this work it is intended to assessment the susceptible weak zones, for a human femur with 70 years old, using the finite element method through ANSYS® program. The main objective is obtaining the stresses distributions, using different values of bone density and their relation with exponential laws for isotropic and orthotropic materials properties

The thickness of the cortical bone in different maxillae using medical images

The aim of this study was to investigate whether there is a relationship between the thickness of the cortical bone of mandible human and the age and the sex of patient. In this work the measure of the cortical bone thickness was obtained in different computed tomography (CT). Different human mandibles were scanned using high resolution micro-CT instrument in which many axial slices were obtained. A total of four medical images were studied and observed. Two different groups were characterized. The first one, with two female maxillae (F): an old and a young patient. The second group of two males mandibles (M), with similar age. A comparison between the male and female sex was also obtained. The cortical bone thickness of the mandible may be affected by tooth extraction, age and sex patient. The use of this type of information is useful for complementary diagnostic information and treatment planning

Cutaneous lesions associated to multiple endocrine neoplasia syndrome type 1

Original article[Abstract] Background  Multiple endocrine neoplasia type 1 (MEN1) is a genetic disease that predisposes to endocrine tumour development. Some cutaneous lesions (angiofibromas, collagenomas, melanosis guttaca, lipomas, melanomas, ‘cafe au lait macules’) have been associated to this syndrome. We compare the prevalence of cutaneous lesion in affected patients with their non‐carrier relatives. Patients and method  We studied 9 patients with MEN1 and 20 non‐carrier, first‐degree relatives. Genetic screening was realized in all of them. Patients were examined by dermatologist, and biopsy was performed when necessary. Results  Patients with MEN1 presented hyperparathyroidism (100%), neuroendocrine tumours of pancreas (66%) and pituitary adenomas (44%); their relatives were free of endocrine features of MEN1. The studied cutaneous lesions were more prevalent in affected patients than in non‐carriers (55.5% vs. 25%; P = 0.029). Odds ratio of developing cutaneous lesions in MEN1 patients was 6.6 (95% confidence interval, 1.09–40.43). The frequency of angiofibromas was lower (22.2%) than the reported in other studies (43–88%), and we did not find any collagenoma. Conclusions  MEN1 is associated to some cutaneous lesions and could be useful for detecting MEN1 carriers in an affected family. Cutaneous lesions should be assessed in MEN1 patients.Instituto de Salud Carlos III; FIS PI051024Xunta de Galicia; PGIDT05PXIC91605P

Applying spatial reasoning to topographical data with a grounded geographical ontology

Grounding an ontology upon geographical data has been pro- posed as a method of handling the vagueness in the domain more effectively. In order to do this, we require methods of reasoning about the spatial relations between the regions within the data. This stage can be computationally expensive, as we require information on the location of points in relation to each other. This paper illustrates how using knowledge about regions allows us to reduce the computation required in an efficient and easy to understand manner. Further, we show how this system can be implemented in co-ordination with segmented data to reason abou

Homocysteine levels in pediatric renal transplant recipients.

Transplant Proc. 2003 May;35(3):1093-5. Homocysteine levels in pediatric renal transplant recipients. Mota C, Fonseca I, Santos MJ, Costa T, Faria MS, Henriques AC, Sarmento AM, Pereira E, Pereira M. Department of Paediatric Nephrology, Maria Pia Children's Hospital, R. da Boavista, 827, 4050-111, Porto, Portugal. [email protected] PMID: 12947872 [PubMed - indexed for MEDLIN

Portuguese study of familial dilated cardiomyopathy: the FATIMA study

Dilated cardiomyopathy (DCM) is a myocardial disease, characterized by ventricular dilatation and impaired systolic function, that in more than 30% of cases has a familial or genetic origin. Given its age-dependent penetrance, DCM frequently manifests in adults by signs or symptoms of heart failure, arrhythmias or sudden death. The predominant mode of inheritance is autosomal dominant, and in these cases mutations are identified in genes coding for cytoskeletal, sarcomeric or nuclear envelope proteins. To date, most studies aimed at molecular diagnosis of DCM have been in selected families, or in larger groups of patients, but screening for mutations in a limited number of genes. Consequently, the epidemiology of mutations in familial DCM remains unknown. There is thus a need for multicenter studies, involving screening for a wide range of mutations in several families and in cases of idiopathic DCM. The present article describes the methodology of a multicenter study, aimed at clinical and molecular characterization of familial DCM patients in the Portuguese population.A miocardiopatia dilatada (MCD) é uma doença do músculo cardíaco caracterizada pela dilatação ventricular e compromisso da função sistólica, sendo possível identificar, numa percentagem superior a 30% dos casos, uma origem familiar ou genética. Dada a penetrância dependente da idade, manifesta-se muitas vezes em adultos por sinais ou sintomas de insuficiência cardíaca, arritmias ou morte súbita. O padrão autossómico dominante predomina, sendo possível identificar, nestes casos, mutações em genes de proteínas do citoesqueleto celular, sarcómero ou membrana nuclear. Até ao momento, a maioria dos trabalhos visando o diagnóstico molecular nos casos de MCD foi realizada em famílias seleccionadas, ou em grupos mais abrangentes de doentes, mas rastreando mutações num número restrito de genes. Consequentemente a epidemiologia das mutações nos casos familiares de MCD continua por esclarecer. É neste contexto que se coloca a necessidade de efectuar estudos multicêntricos, envolvendo uma pesquisa mutacional diversificada em várias familias e nos casos idiopáticos de MCD. O presente artigo descreve a metodologia de um estudo multicêntrico que tem como objectivo a caracterização clínica e molecular de casos familiares de MCD na população portuguesa

The thickness of the cortical bone in different maxillae using medical images

The aim of the present study was to investigate whether there is a relationship between the thicknesses of the cortical bone of mandible human and the age and the sex of patient. In this work the measure of the cortical bone thickness was obtained in different computed tomography (CT) dental of medical images. Different human mandibles were scanned using high resolution micro‐CT instrument in which many axial slices were obtained, see figure 1. Pixel by pixel for each slice and using image control system software, different layers were measured. A total of four medical images were studied and observed. Two different groups were characterized. The first one, with two female mandibles (F): an old and a young patient. The second group of two males mandibles (M), with similar age. A comparison between the male and female sex was also obtained. The cortical bone thickness of the mandible may be affected by tooth extraction, age and sex patient. The use of this type of information is useful for complementary diagnostic information and treatment planning

Hyperhomocysteinemia in Renal Transplantation: Preliminary Results

Cardiovascular disease (CVD) is a major cause of morbidity and mortality after renal transplantation (RT).[1] and [2] The excess risk of CVD in RT is due in part to a higher prevalence of established atherosclerotic risk factors, including hypertension, dyslipidemia, diabetes, obesity, and physical inactivity.[1] and [2] However, some renal-related risk factors like immunosuppressive medication and residual renal insufficiency also contribute to this excess CVD risk and may complicate the management of dyslipidemia and hypertension in this population.[1] and [2] Accordingly, there is a compelling need to identify and safely manage other putative CVD risk factors among RT patients. Elevated plasma homocysteine is emerging as an important risk factor for cardiovascular disease in general populations.[3] and 4 R Clarke, L Daly and K Robinson et al., N Engl J Med 324 (1991), p. 1149. View Record in Scopus | Cited By in Scopus (1372)[4] Some studies have demonstrated that hyperhomocysteinemia is present in patients with impaired renal function and is associated with CVD.[5], [6] and [7] Only a small number of studies are available on the prevalence and determinants of hyperhomocysteinemia in renal transplant recipients.[8], [9], [10], [11], [12], [13], [14] and [15] We undertook this study to 1. estimate the prevalence of hyperhomocysteinemia in renal transplant recipients; 2. examine the relationships between plasma total homocysteine (tHcy) and its metabolic determinants vitamin B6, vitamin B12, and folic acid; and 3. identify other determinants of tHcy

CONCENTRAÇÕES DE LACTATO SANGUÍNEO E DETERMINAÇÃO DO V4 DE CAVALOS DA RAÇA ÁRABE DURANTE TESTE DE EXERCÍCIO PROGRESSIVO EM ESTEIRA DE ALTA VELOCIDADE

Com este estudo objetivou-se avaliar as alterações da concentração de lactato sanguíneo e determinar o V4 de cavalos da raça Árabe submetidos ao teste de exercício progressivo em esteira de alta velocidade. Onze eqüinos adultos foram submetidos a um período de condicionamento e ao teste de exercício progressivo em esteira de alta velocidade. Nas condições em que foi realizado o experimento foi possível concluir que o protocolo de exercício proposto para aplicação do teste padrão de exercício progressivo, mostrou-se eficaz na indução de respostas metabólicas e fisiológicas para várias intensidades de exercício de cavalos da raça Árabe durante o trabalho físico em esteira de alta velocidade. As concentrações de lactato sanguíneo elevam-se exponencialmente a partir da velocidade de exercício de 8,0m/s, determinada como o V4 para o presente estudo. Blood concentration of lactate and determination of V4 in Arabian horses during a incremental exercise test performed at a high-speed treadmill Abstract The purpose of this study was to evaluate the changes in the blood lactate concentrations and to determine the V4 in Arabian horses, submitted to incremental exercise test performed on a high-speed treadmill. Eleven adult horses underwent a conditioning period as well as incremental exercise test performed on a high-speed treadmill. Under the circumstances that the experiment was developed, it was possible to conclude that the results obtained during the incremental exercise test were useful to assess the horses metabolic capability. The blood lactate levels exponentially increase beyond the speed of 8.0 m/s, determined as the V4 for this study