[Diagnosis and management of the aminoacidopathies (author's transl)].

Since its description by Garrod, the concept of the "inborn errors of metabolism" has become a clinical reality that the physician cannot ignore. The aminoacidopathies represent a group historically notable in that they represent the first diseases recognized as metabolic in origin (alcaptonuria, albinism) and for which some measure of therapeutic success can be claimed. Dietary prophylaxis of the encephalopathy of phenylketonuria is a prominent example.

Radiological signs of mucolipidosis II or I-cell disease. A study of nine cases.

Nine cases of mucolipidosis II are presented with illustrations and a discussion of specific radiologic features: these distinguish Mucolipidosis II from other storage diseases.

Phenylalanine analogues as inhibitors of phenylalanine-hydroxylase from rat liver. New conclusions concerning kinetic behaviors of the enzyme.

The conversion of phenylalanine to tyrosine is catalysed by phenylalanine-hydroxylase. The substrate phenylalanine shows two effects: (1) allosteric transition at low phenylalanine concentrations, (2) excess substration inhibition. The molecular structure of phenylalanine-hydroxylase has not yet been elucidated.

[Langer's type mesomelic dwarfism. Apropos of a case].

One case of Lnger's type mesomelic dwarfism is reported in a 7-day old newborn. Height retardation was severe and concerned essentially the middle segment of limbs. Cubituses and fibulae were hypoplastic.

[N-Acetyl-beta-hexosaminidases. Present knowledge regarding chemical characterization and genetic relationships (author's transl)].

In recent years considerable attempts have been directed towards the chemical characterization of lysosomal hexosaminidases. Hexosaminidase A had been shown to be a heterotetramer: alpha2 beta2 and hexosaminidase B a homotetramer: beta4. Studies of GM2 gangliosidosis supported this theory, in fact alpha and beta chains require genes on different chromosomes.

Carbamyl-phosphate-synthetase deficiency with neonatal onset of symptoms.

The clinical course and biochemical findings in a case of carbamyl-phosphate-synthetase deficiency are described. The patient, a boy, presented 48 h after birth with rapidly developing hypotonia and hypothermia. Pulmonary haemorrhage, melaena and haematemesis ensued and despite ventilatory assistance and peritoneal dialysis the patient died on the fifth day.

[A new complex polymalformative syndrome (author's transl)].

The authors discuss the nosological position and the aetiology of a complex of malformations affecting a boy, born at the end of a 40-week pregnancy with a weight of 1420 g and height of 42.5 cm, who died at the age of 3 1/2 months. The case presented an association of an acrocephalosyndactyly, phalangeal hypoplasias with anonychia, aplasia of the abdominal muscles, a genital hypoplasia with cryptorchidism and hypospadias, patches of lipodystrophy localised on the outside of the arms, at the folds of the elbow and the popliteal fossae.

Ocular findings in I-cell disease (mucolipidosis type II).

The ultrastructural study of the eyes in seven patients affected with I-cell disease (mucolipidosis type II) revealed important changes in the corneal, scleral, and uveal fibroblasts, while other cells were rarely involved. This explains the inconstant corneal clouding and the absence of ophthalmoscopic abnormalities clinically. At any moment of a patient's life, conjunctival biopsy specimens show characteristic alterations and allow the rapid and secure diagnosis of I-cell disease.

Study of blood aminoacids in experimental hyperphenylalaninemia.

Hyperphenylalaninemia was induced in rats treated with p. chlorophenylalanine and cotrimoxazole, without administration of excess phenylalanine. Enhancement of phenylalaninemia and abnormalities in other serum amino acids were similar to those found in phenylketonuric patients, out of the restricted diet.