Influence of body composition on the bone mass of postmenopausal women

Aims: To investigate the influence of body weight (BW), fat mass (FM) and lean mass (LM) on the bone mineral density (BMD) of several areas of the skeleton. Participants: Sixty one white postmenopausal women (50.1 + 4.8 years). Measurements: Measurement of BMD by dual energy x-ray absorptiometry. The results were analyzed by linear regression and the slopes of each curve were compared. Results: The results showed that the correlations between BW, FM and LM to BMD were positive, whilst the correlations between age and years since menopause to BMD were negative. LM was the main factor that influence BMD in almost all areas. Conclusions: FM and LM present a positive effect on BMD, although LM is the main determinant of bone mass. Moreover, higher values of LM and FM present a protective effect against the reduction of BMD combined with menopause. Therefore postmenopausal women with low BM, especially low LM, present serious risk for developing osteoporosis.

Proposal for a compputer program for 99m Tc-DTPA alveolar capillary clearance study

Os radioaerossóis e a cintilografia de ventilaçäo tem papeis bem definidos na rotina medica nuclear. Estudos sobre o clearance alveolo-capilar de tecnécio-99m marcando o ácido dietileno triamino penta-acético (99mTc-DPTA) permitem um diagnóstico precoce, ao menos presuntivo, de infecçöes pulmonares oportunistas, com uma sensibilidade maior que a dos estudos convencionais. Nós desenvolvemos um programa no computador acoplado à câmara de cintilaçäo para processar as imagens adquiridas, resultando em modo rápido e eficiente para quantificaçäo do clearance alveolo-capilar. Realizamos, a título de ilustraçäo, um teste clínico em um voluntário (35 anos, fumante, normal), que nos mostrou ser o programa adequado do ponto de vista de processamento. Adicionalmente, os resultados (pulmäo direito: 2,22 por cento/min; pulmäo esquerdo: 1,86 por cento/min) estäo de acordo com os dados encontrados na literatura