Effect of temperature on bone tissue: histological changes.

The analysis of burned human remains has been of great interest among forensic anthropologists largely due to the difficulty that their recovery, classification, reconstruction, and identification present. The main purpose of this analysis is to present histological methodology for the interpretation of bones altered by thermal processes. We include analyses of the microscopic changes among bones exposed to different temperatures, with the goal of establishing categories of histological morphology in relation to fire temperature. Samples of bone (ilium) were exposed systematically to controlled temperatures. Analysis of the resulting histological changes has allowed the formation of a clear four-stage classification of the alterations observed. This classification should prove useful in assessing bone changes in relation to temperature of exposure, particularly in cases where this temperature was previously not known.

Relation between body mass index and bone mineral density among haemodialysis patients with chronic kidney disease.

UNLABELLED: Renal osteodystrophy is a serious problem for patients with chronic kidney disease. Measurements of bone mineral density, T-score and Z-score were taken in the lumbar region and femur of 73 patients who were being treated on the haemodialysis programme. These measurements were compared with the anthropometric values of weight, height and body mass index (BMI) obtaining a positive correlation between them. INTRODUCTION: Alterations in the bone mineral metabolism are an important cause of morbidity and mortality among haemodialysis patients with chronic renal failure. Bone mass diminution, together with fracture risk, is a frequent finding in these patients; this fact is explained by different factors, amongst which are those related to their anthropometric values. MATERIALS AND METHODS: Bone mineral density (BMD) was studied, T-score and Z-score measurements were taken in the neck of the femur, trochanter, intertrochanter, 1/3 of proximal femur, Ward's triangle and L2, L3 and L4 vertebrae; body composition was also studied. With this aim, DXA densitometry was used on 73 haemodialysis patients (40 men and 33 women). The mean of the total haemodialysis time in these patients was 9.7 years. The group showed a very significant positive correlation between BMD, weight, height, BMI, fractures, dialysis time and intact PTH. CONCLUSIONS: CKD patients undergoing the haemodialysis programme show a significant BMD reduction, which affects both lumbar spine and femur. Weight and height affect BMD and bone change, being thus important factors of prediction for fracture risk. Furthermore, BMI is the main determinant of BMD, a finding that is confirmed in the units in this study and with the evidence described by other authors (Negri et al. (2005).