1,25(OH)2D3 is not the only D metabolite involved in the pathogenesis of osteomalacia.

Three patients are described in whom there was no simple correlation between plasma 1,25(OH)2D3 concentration and the occurrence of osteomalacia. One patient had severe osteomalacia with high plasma 1,25(OH)2D3 and normal mineral ion product; the second had a normal mineral ion product and no evidence of osteomalacia even though plasma 1,25(OH)2D3 was undetectable; and the third had osteomalacia, low plasma 1,25(OH)2D3 and a reduced mineral ion product. In considering these data in the light of presently available information, it is concluded that osteomalacia can occur as a consequence of a lack of a vitamin D metabolite other than 1,25(OH)2D3, or a consequence of a reduced mineral ion product, but not as a consequence of 1,25(OH)2D3 lack if the mineral ion product is normally maintained and other D metabolites are present.

Anomalous left coronary artery in the infant: recovery of ventricular function following early direct aortic implantation.

A successful direct aortic implantation of an anomalous left coronary artery (ALCA) in an infant is reported. Detailed evaluation of postoperative ventricular function, including repeat cardiac catheterization and serial echocardiography, demonstrated progressive enhancement of ventricular contractility and function. Postoperative angiography confirmed vascular patency.

Primary hyperparathyroidism with intermittent hypercalcaemia: serial observations and simple diagnosis by means of an oral calcium tolerance test.

Ten patients with subtle primary hyperparathyroidism and intermittent hypercalcaemia were followed serially for periods of 2--18 months (mean 10 months). Fasting serum calcium was elevated (greater than 10.6 mg/dl) in only 20% of determinations and fluctuated widely (9.

Surgical palliation in aortic atresia.

In an infant with aortic atresia, two surgical procedures resulted in a 45 day postoperative survival. An atrial septectomy was initially performed. This was followed by the insertion of a Dacron graft from the main pulmonary artery to the descending thoracic aorta; the pulmonary artery was handed distal to the graft and the ductus arteriosus was ligated.

The importance of circulating 1,25-dihydroxyvitamin D in the pathogenesis of hypercalciuria and renal-stone formation in primary hyperparathyroidism.

Fifty patients with primary hyperparathyroidism were studied with an oral calcium-tolerance test, measurements of plasma levels of vitamin D metabolites, and determination of calcium excretion on both a low-normal (400 mg) and high-normal (1000 mg) calcium intake. There were strong positive correlations between plasma levels of 1,25-dihydroxyvitamin D (1,25(OH)2D) and both the calciuric response to the calcium-tolerance test (r = +0.75, P less than 0.

Beyond averaging. II. Single-trial classification of exogenous event-related potentials using stepwise discriminant analysis.

Using stepwise discriminant analysis (SWDA), single-trial event-related potentials (ERPs) were classified as to whether they were elicited by a checkerboard presented to the upper or lower visual half-field. Discriminant functions were computed on the basis of 'training sets' constructed of upper and lower half-field ERPs, and applied to 'test sets' of other ERPs elicited by the same stimuli. Individual-subject discriminant functions for data recorded at PZ classified the single ERPs in the test sets with a mean accuracy of 83.

Assay for vitamin D2 and vitamin D3 in plasma of dairy cows: changes after massive dosing of vitamin D3.

A sensitive, precise assay for vitamin D in plasma is described. Three to five milliliters of plasma were extracted with methanol:methylene chloride (2:1). The lipid extract was chromatographed on Sephadex LH-20 and then on lipidex-5000 columns.

25-Hydroxyvitamin D3 26,23-lactone: a new in vivo metabolite of vitamin D.

A major vitamin D metabolite was isolated in pure form from the blood plasma of chicks either maintenance levels or large doses of vitamin D3. The isolation involved methanol-chloroform extraction and five column chromatographic procedures. The metabolite purification and elution position on these columns were followed by a competitive protein binding assay.

Parathyroid function and vitamin D metabolism during human growth hormone replacement.

Changes in calcium and phosphorus metabolism were studied in nine children with GH deficiency before and during human GH replacement therapy. Parathyroid function and serum concentrations of physiologically important vitamin D metabolites were examined to determine their relationship to changes in mineral metabolism. By comparison with pretreatment values, the GH-treated children showed significant increases in growth rate and renal tubular phosphate reabsorption and a significant decrease in urinary calcium excretion after a standardized oral load.

Determination of vitamin D and its metabolites in plasma from normal and anephric man.

A multiple assay capable of reliably determining vitamins D(2) and D(3) (ergocalciferol and cholecalciferol), 25(OH)D(2) (25-hydroxyvitamin D(2)) and 25(OH)D(3) (25-hydroxyvitamin D(3)), 24,25(OH)(2)D (24,25-dihydroxyvitamin D), 25,26(OH)(2)D (25,26-dihydroxyvitamin D) and 1,25(OH)(2)D (1,25-dihydroxyvitamin D) in a single 3-5ml sample of human plasma was developed. The procedure involves methanol/methylene chloride extraction of plasma lipids followed by separation of the metabolites and purification from interfering contaminants by batch elution chromatography on Sephadex LH-20 and Lipidex 5000 and by h.p.

Potential use of 1,25-dihydroxycholecalciferol for prevention of parturient paresis.

Twelve cows, at least third parity, were assigned randomly to either a control or treatment group. Treated cows received .4 mg of the vitamin D metabolite, 1,25-dihydroxycholecalciferol intramusculary in 5 ml corn oil.

Interrupted aortic arch operation in the first week of life: hemodynamic and angiographic evaluation one year later.

Operation for interrupted aortic arch (IAA) was successful in 2 infants during the first week of life. Both had postoperative hemodynamic and angiographic evaluation at one year of age. The first infant had a type A IAA, and prostaglandins were infused to prevent ductal closure prior to the insertion of a graft between the two ends of the interrupted aorta.

Pericardial calcification in childhood.

Calcific constrictive pericarditis (CCP) in a three-year-old child with symptoms of cardiac compression was confirmed by cardiac catheterization and angiography. Histologic examination of the pericardial tissue removed at operation revealed a tuberculous etiology. Though unusual in the pediatric age group, constrictive pericarditis (CP) may occur in children, most often as a complication of tuberculosis.

25-hydroxycholecalciferol for prevention of "milk fever" in dairy cows.

Intramuscular injections of 4 or 8 mg 25-hydroxycholecalciferol (25-OH D3) in 5 ml corn oil given three days before the predicted calving date and repeated at weekly intervals until calving effectively reduced the incidence of parturient paresis. Drug efficacy was improved in cows receiving low to normal recommended levels of dietary phosphorus prepartum. With proper management techniques, 25-OH D3 could prevent parturient paresis in dairy cattle.

Right aortic arch, right patent ductus arteriosus, and mirror-image branching of the brachiocephalic vessels.

Two patients with a right aortic arch, right patent ductus arteriosus, and mirror-image branching of the brachiocephalic vessels are described. The clinical, angiographic, and surgical findings in these two cases are detailed, and a description of the embryologic basis for these anomalies is given.