We describe two siblings from a consanguineous family with autosomal recessive Fanconi's syndrome and hypophosphatemic rickets. Genetic analysis revealed a homozygous in-frame duplication of 21 bp in SLC34A1, which encodes the renal sodium-inorganic phosphate cotransporter NaPi-IIa, as the causative mutation. Functional studies in Xenopus laevis oocytes and in opossum kidney cells indicated complete loss of function of the mutant NaPi-IIa, resulting from failure of the transporter to reach the plasma membrane. These findings show that disruption of the human NaPi-IIa profoundly impairs overall renal phosphate reabsorption and proximal-tubule function and provide evidence of the critical role of NaPi-IIa in human renal phosphate handling.

Avascular necrosis (AVN) of the head of the femur is a potentially crippling disease which mainly affects young adults. Although treatment by exposure to hyperbaric oxygen (HBO) is reported as being beneficial, there has been no study of its use in treated compared with untreated patients. We selected 12 patients who suffered from Steinberg stage-I AVN of the head of the femur (four bilateral) whose lesions were 4 mm or more thick and/or 12.5 mm or more long on MRI. Daily HBO therapy was given for 100 days to each patient. All smaller stage-I lesions and more advanced stages of AVN were excluded. These size criteria were chosen in order to compare outcomes with an identical size of lesion in an untreated group described earlier. Overall, 81% of patients who received HBO therapy showed a return to normal on MRI as compared with 17% in the untreated group. We therefore conclude that hyperbaric oxygen is effective in the treatment of stage-I AVN of the head of the femur.

FDG-PET/CT may be useful and complementary to other imaging modalities for the detection of recurrent pediatric sarcomas, especially at the primary site. Its potential advantages and limitations compared with conventional imaging modalities need to be further investigated in larger homogenous patient groups.

After extensive suprasellar operations for hypothalamic tumor removal, some patients develop Cushing-like morbid obesity while they receive replacement doses of glucocorticoids. In this study, we examined the hypothesis that target tissue conversion of inactive 11-ketosteroids to active 11 beta-OH glucocorticoids might explain the obesity of some patients with hypothalamic lesions. Toward this aim, we studied 10 patients with hypothalamic obesity and secondary adrenal insufficiency and 6 control Addisonian patients while they were on glucocorticoid replacement therapy. Pituitary hormone deficiencies were replaced when medically indicated. Twenty-four-hour urine was collected after a single oral dose of 12 mg/m(2) hydrocortisone acetate. The ratios of free and conjugated cortisol (F) to cortisone (E) and their metabolites, [tetrahydrocortisol (THF)+5 alpha THF]/tetrahyrdocortisone (THE), dihydrocortisols/dihydrocortisones, cortols/cortolones, and (F+E)/(THF+THE+5 alpha THF), were considered to represent 11 beta-hydroxysteroid dehydrogenase (HSD) activity. The 11-OH/11-oxo ratios were significantly higher in the urine of patients with hypothalamic obesity. The 11-OH/11-oxo ratios, however, did not correlate with the degree of obesity, yet a significant correlation was found between conjugated F/E and the ratio of visceral fat to sc fat measured by computerized tomography at the umbilical level. The consequence of increased 11 beta-HSD1 activity and the shift of the interconversion toward cortisol may contribute to the effects of the latter in adipose tissue. We propose that deficiency of hypothalamic messengers after surgical injury induces a paracrine/autocrine effect of enhanced glucocorticoid activity due to up-regulated 11 beta-HSD1 activity.

To assess the physiologic and clinical relevance of newer noninvasive measures of vascular compliance, computerized arterial pulse waveform analysis (CAPWA) of the radial pulse was used to calculate two components of compliance, C1 (capacitive) and C2 (oscillatory or reflective), in 87 normotensive (NlBP, n ‫؍‬ ‫؍‬ 20), untreated hypertensive (HiBP, n ‫؍‬ ‫؍‬ 21), and treated hypertensive (HiBP-Rx, n ‫؍‬ ‫؍‬ 46) subjects. These values were compared with two other indices of compliance, the ratio of stroke volume to pulse pressure (SV/PP) and magnetic resonance imaging (MRI)-based aortic distensibility; and were also correlated with demographic and biochemical values.The HiBP subjects displayed lower C1 (1.34 ؎ ؎ 0.09 v 1.70 ؎ ؎ 0.11 mL/mm Hg, significance [sig] ‫؍‬ ‫؍‬ .05) and C2 (0.031 ؎ ؎ 0.003 v 0.073 ؎ ؎ 0.02 mL/mm Hg, sig ‫؍‬ ‫؍‬ .005) than NlBP subjects. This was not true for C1 (1.64 ؎ ؎ 0.08 mL/mm Hg) and C2 (0.052 ؎ ؎ 0.005 mL/mm Hg) values in HiBP-Rx subjects. The C1 (r ‫؍‬ ‫؍‬ 0.917, P < < .0001) and C2 (r ‫؍‬ ‫؍‬ 0.677, P < < .0001) were both closely related to SV/PP, whereas C1 (r ‫؍‬ ‫؍‬ 0.748, P ‫؍‬ ‫؍‬ .002), but not C2, was significantly related to MRI-determined aortic distensibility.Among other factors measured, age exerted a strong negative influence on both C1 (r ‫؍‬ ‫؍‬ ؊0.696, P < < .0001) and C2 (r ‫؍‬ ‫؍‬ ؊0.611, P < < .0001) compliance components. Positive correlations were observed between C1 (r ‫؍‬ ‫؍‬ 0.863, P ‫؍‬ ‫؍‬ .006), aortic distensibility (r ‫؍‬ ‫؍‬ 0.597, P ‫؍‬ ‫؍‬ .19) and 24-h urinary sodium excretion, and between C1-and MR spectroscopydetermined in situ skeletal muscle intracellular free magnesium (r ‫؍‬ ‫؍‬ 0.827, P ‫؍‬ ‫؍‬ .006), whereas C2 was inversely related to MRI-determined abdominal visceral fat area (r ‫؍‬ ‫؍‬ ؊0.512, P ‫؍‬ ‫؍‬ .042) and fasting blood glucose (r ‫؍‬ ‫؍‬ ؊0.846, P ‫؍‬ ‫؍‬ .001).Altogether, the close correspondence between CAPWA, other compliance techniques, and known cardiovascular risk factors suggests the clinical relevance of CAPWA in the assessment of altered vascular function in hypertension. Am J Hypertens 2000;13:1243-1249