Automated computation of femoral angles in dogs from three-dimensional computed tomography reconstructions: Comparison with manual techniques.

The aim of this ex vivo study was to test a novel three-dimensional (3D) automated computer-aided design (CAD) method (aCAD) for the computation of femoral angles in dogs from 3D reconstructions of computed tomography (CT) images. The repeatability and reproducibility of three manual radiography, manual CT reconstructions and the aCAD method for the measurement of three femoral angles were evaluated: (1) anatomical lateral distal femoral angle (aLDFA); (2) femoral neck angle (FNA); and (3) femoral torsion angle (FTA). Femoral angles of 22 femurs obtained from 16 cadavers were measured by three blinded observers. Measurements were repeated three times by each observer for each diagnostic technique. Femoral angle measurements were analysed using a mixed effects linear model for repeated measures to determine the levels of intra-observer agreement (repeatability) and inter-observer agreement (reproducibility). Repeatability and reproducibility of measurements using the aCAD method were excellent (intra-class coefficients, ICCs≥0.98) for all three angles assessed. Manual radiography and CT exhibited excellent agreement for the aLDFA measurement (ICCs≥0.90). However, FNA repeatability and reproducibility were poor (ICCs<0.8), whereas FTA measurement showed slightly higher ICCs values, except for the radiographic reproducibility, which was poor (ICCs<0.8). The computation of the 3D aCAD method provided the highest repeatability and reproducibility among the tested methodologies.

Powder-based 3D printing for bone tissue engineering.

Bone tissue engineered 3-D constructs customized to patient-specific needs are emerging as attractive biomimetic scaffolds to enhance bone cell and tissue growth and differentiation. The article outlines the features of the most common additive manufacturing technologies (3D printing, stereolithography, fused deposition modeling, and selective laser sintering) used to fabricate bone tissue engineering scaffolds. It concentrates, in particular, on the current state of knowledge concerning powder-based 3D printing, including a description of the properties of powders and binder solutions, the critical phases of scaffold manufacturing, and its applications in bone tissue engineering. Clinical aspects and future applications are also discussed.

Association of white blood cell count with systolic blood pressure within the normotensive range.

Hypertension and inflammation promote cardiovascular disease (CVD). Even high normal systolic blood pressure (SBP) is associated with increased CVD risk. We assessed the relationship of elevated SBP within the normotensive range and white blood cell (WBC) count. This is a cross-sectional study of 3484 white asymptomatic individuals (mean age: 43+/-8 years, 79% males) without hypertension with SBP<140 mm Hg. White blood cell count >or=75th percentile (8.35 x 10(9) cells/l) was considered cutoff for elevated WBC. Subjects were classified into three levels of SBP (first: <120 mm Hg, n=1,176, 34%; second: 120-129 mm Hg, n=1,654, 47%; third: 130-139 mm Hg, n=654, 19%). Mean WBC count increased linearly across SBP categories (first: 6.14+/-1.54, second: 6.20+/-1.52, third: 6.41+/-1.62, P=0.02 for trend). There was a linear increase in prevalence of elevated WBC across higher SBP categories (22, 24 and 28%, P=0.02). As compared to those with SBP<120 mm Hg, in multivariate linear regression analyses (adjusting for age, gender, smoking status, diabetes, body mass index, physical activity, cholesterol/high-density lipoprotein cholesterol ratio) WBC count was significantly higher among participants with SBP 130-139 mm Hg (regression coefficient: 2.64, 95% confidence interval: 1.04-4.24, P=0.001). Odds ratio for prevalence of elevated WBC with SBP<120 mm Hg as reference group was 1.14 (0.92-1.41) for SBP 120-129 mm Hg and 1.50 (1.15-1.92) for SBP 130-139 mm Hg. In conclusion, Higher SBP within the normotensive range is also associated with elevated WBC count. Further studies are needed to clarify the role of inflammation in high normal SBP and associated CVD risk.

Improving accuracy of bone resections using robotics tool holder and a high speed milling cutting tool.

The use of non-cemented prosthetic components in implant surgery is demanding a high quality of bone beds in order to allow for a good level of osseointegration. Two parameters are significant in the evaluation of the quality of the host bone: roughness, which reports on the presence of gaps and peeks, and flatness, which reports on the total percentage of bone which lies in a given interval from the prosthesis. Robot assisted cutting of 32 pig femours and tibiae was performed using various techniques and options. This paper demonstrates roughness and flatness can be taken of the order of the limits necessary for osseointegration, by using a milling cutting tool mounted on a strong support, in this case a robot arm, improving on the results obtained by similar studies referred to hand sawed bones by 10 times.

Cintigrafia do miocardio com talio-201 em pacientes com prolapso da valva mitral, com e sem coronariopatia. / Myocardial scintillography with thalium 201 in patients with mitral valve prolapse, with or without coronary disease

Trinta pacientes com dor precordial e prolapso da valva mitral a cineangiografia e ao ecocardiograma modo-M foram submetidos a cintigrafia do miocardio com Talio-201 (201Tl) associado ao teste ergometrico (TE). Os pacientes foram assim distribuidos: grupo I (GR I) - 18 pacientes portadores de prolapso da valva mitral com arterias coronarias normais, dos quais 10 apresentavam TE positivo (55,6%) e 8 negativos; a cintigrafia do miocardio com 201Tl foi normal em 14 pacientes (77,8%); 4 apresentaram isquemia transitoria (3 em parede inferior e 1 em parede lateral); grupo II (GR II) - constituido por 12 pacientes com prolapso da valva mitral de doenca obstrutiva coronariana grave (lesoes maior igual 60% em pelo menos um vaso principal da circulacao coronaria), dos quais 9 apresentavam TE positivo (75%) e 3 negativo. A cintigrafia do miocardio com 201Tl apresentou defeitos de captacao em 9 (75%), sendo 6 com isquemia transitoria e 3 definitiva; nos outros 3 pacientes o mapeamento foi normal. Baseados nestes achados, os autores concluem que a cintigrafia do miocardio com 201Tl foi mais sensivel para detectar presenca de doenca obstrutiva coronariana em portadoes de prolapso da valva mitral (PVM) que o TE, apesar de um pequeno numero (22,2%) de pacientes com PVM e coronarias normais exibir defeitos de captacao do radioindicador

Formation of acetoacetate from 3-hydroxy-3-methylglutarate by rat liver and isolation of a mitochondrial coenzyme A-transferase activity involved.

1. Formation of acetoacetate from 3-hydroxy-3-methylglutarate was observed in the perfused rat liver. Production of 3.5mumol of acetoacetate/h per g of tissue was obtained. 2. Formation of acetoacetate was catalysed mainly by the mitochondrial fraction of the homogenized liver, at a rate of 62nmol/h per mg of protein. 3. Experiments with hydroxy-[3-(14)C]methylglutarate demonstrated that the acetoacetate formed was derived mainly from this compound. 4. A mitochondrial transferase activity catalysing the transfer of a CoA molecule from succinyl-CoA (3-carboxypropionyl-CoA) to hydroxymethylglutarate was shown. The K(m) value for hydroxymethylglutarate was 5x10(-3)m.