The changing picture of pseudotumor cerebri in children

Among 38 children with pseudotumor cerebri only 3 cases were due to ear disease or its complications. The commonest cause was a refeeding syndrome either due to nutritional deprivation or as an early finding in the treatment of cystic fibrosis. It is uncommon to find the cause of pseudotumor in older children but in those under 6 years the cause was found in 85%. Because of the adverse effects of steroids we use this treatment in the more resistant cases.     

Nonsurgical and surgical treatments for sleep apnea

This article reviews the various treatments currently available for obstructive sleep apnea and discusses some newer and more controversial therapies. Decisions regarding the best treatment should be aimed at relieving the unique levels of obstruction in each patient. Increased controlled outcome trials will be needed to assess the success of each therapy in certain subpopulations in comparison with CPAP. As these data become available, the roles of each therapy will become clearer in treating this major health problem.     

Characterization of cells with high alkaline phosphatase activity derived from human bone and marrow: preliminary assessment of their osteogenicity

Confluent cellular layers are reproducibly obtained (from 21 of 24 specimens) by outgrowth from composite pieces of human trabecular bone and marrow. The cells resemble fibroblasts in terms of morphology, esterase profile, and production of collagen type 1. However, the cells displayed some osteoblastlike features. Both the primary outgrowths and passaged cultures had high alkaline phosphatase activities (37 nmols min-1 X microgram DNA-1) in the range displayed by embryonic osteoblastlike cells. The cellular alkaline phosphatase activity, which showed similarity to the bone isoenzyme on kinetic criteria, was stimulated by 1,25-dihydroxyvitamin D3 but decreased by PTH (1-34). In addition, the cell preparations were shown to increase osteocalcin (bone Gla protein) production in response to 1,25-dihydroxyvitamin D3. The osteogenic potential of the bone and marrow-derived cells has been assessed in an in vivo diffusion chamber assay in which congenitally athymic (nude) mice were used as hosts. None of the 25 chambers examined showed evidence of osteogenesis, although the cells remained viable and fibroblastlike. The alkaline phosphatase activities decreased to less than 1% of the original, high in vitro values. The findings question the hypothesis that bone and marrow-derived cells are osteoblasts or osteoblastlike cells, rather than a mixture of cell lines of the bone and marrow stromal system.     

The relationship between muscle surface pH and oxygen transport.

The relationship between muscle surface pH (pHM) and the arterial-venous oxygen content difference (AVO2D) was studied in 4 patients undergoing reconstructive arterial surgery and in 6 patients undergoing acute normovolemic hemodilution. There was a consistent inverse relation between pHM in the ischemic lower extremity and the femoral AVO2D before, during and after aortic clamping. There was also an inverse relation between AVO2D and pHM during hemodilution. These data confirm that pHM is a reliable indicator of tissue perfusion and correlates with the AVO2D.