Alopecia/mental retardation syndrome

We report on an African-American patient with alopecia universalis, microcephaly, hypogonadism, and mental and growth retardation, and compare his phenotype to others with recessive alopecia/mental retardation syndromes in the literature. Our patient represents the first case reported from nonconsanguineous African-American parents. © 1995 Wiley-Liss, Inc.     

Energy supplementation and the nutritional status of hemodialysis patients

Twenty-one patients undergoing regular hemodialysis completed a trial of energy supplementation. Nine patients added the glucose polymer Polycose to their usual diet and 12 acted as control subjects. The supplemented patients were asked to incorporate 100 or 150 g polymer, equivalent to 1600 or 2400 kJ (400 or 600 kcal) into their usual diet, daily for 6 mo. This resulted in a mean increase in energy intake of 1630 kJ (p less than 0.05) and a mean weight gain of 3.1 kg (p less than 0.005). The addition of glucose polymer to the diet resulted in a mean increase in body fat of 1.8 kg and the lean body mass increased by 1.3 kg. No significant effect on plasma triglycerides, urea, or creatinine was detected. The intake of macro- and micronutrients was not adversely affected and no clinical or psychological side effects were reported. Follow-up of these patients showed that the weight gain was maintained after 6 mo. Glucose polymer was an effective energy supplement that had beneficial effects on the nutritional status of hemodialysis patients.     

Aspirin, protein transacetylation and inhibition of prostaglandin synthetase in the kidney

1 The effect of aspirin on the kidney has been investigated in mice and rabbits. [Acetyl-¹⁴C]-aspirin was administered intraperitoneally in doses ranging from subtherapeutic to toxic. The degree of acetylation of protein was determined by the radioactivity remaining on protein precipitates of renal cortex and medulla after sequential washing designed to remove non-covalently bound material. Controls were established, by the use of [carboxyl-¹⁴C]-aspirin.

2 The acetyl-¹⁴C residue was bound to renal proteins in a linear manner in increasing amounts with increasing dosage up to 100 mg/kg. The [carboxyl-¹⁴C]-aspirin was not bound and thus the salicylate portion of the molecule was not bound covalently to the renal protein. The time course of the acetylation was rapid, consistent with the rate of aspirin absorption. The disappearance of acetylated protein was slow, with a T_1/2 of 112.5 h in the renal cortex, and 129.5 h in the renal medulla.

3 Differential centrifugation, Sephadex chromatography and gel electrophoresis were carried out on tissue homogenates to determine the site of acetylation. The acetylation was greatest in the microsomal fraction, although all protein fractions showed some degree of acetylation.

4 The prostaglandin synthetase activity of a particulate preparation from rabbit kidney was determined by a spectrophotometric assay of malondialdehyde formation. Aspirin (10 mg/kg, i.v.) significantly inhibited prostaglandin synthetase in the renal cortex and medulla.

5 Aspirin and renal proteins undergo a transacetylation reaction resulting in stable acetylated protein, with acetylation being greatest in the microsomal fraction. Aspirin has been shown to inhibit prostaglandin synthetase and this could lead to functional impairment of the tissue.