Nodular lesions of choroid plexus in Hurler disease.

Neuropathologic examination of six brains from children with Hurler disease revealed nodular lesions in the glomus of choroid plexus caused by proliferation of vacuolated pericytes, fibroblasts, and arachnoid cells on the background of collagenized and myxoid stroma. This localization of lesions can be explained by the presence of a rich vascular network, as well as cellular heterogeneity greater in the glomus than in other parts of the choroid plexus or in the brain parenchyma. The development of nodules did not correlate with the age, severity of hydrocephalus, or the degree of expansion of the perivascular spaces in the brain.

A comparison of the demography, clinical profile and treatment of adopted and non adopted children at a children's mental health centre.

A retrospective analysis of adopted and non adopted children attending a children's mental health centre between 1959 and 1973 indicated a higher than expected number of males and a significantly higher number of professional fathers than expected in the adopted group. A sub-group of adopted children identified as having learning problems by reports of the parents and teachers had a different pattern of test scores on the Wechsler Intelligence Scale for Children from a non adopted group, who were also selected for learning difficulties. On the parent's and clinician's ratings, the adopted group had more parent-identified hyperactivity symptoms and clinicians' diagnoses of hyperactivity.

Purification and structure of human liver aspartylglucosaminidase.

We have recently diagnosed aspartylglucosaminuria (AGU) in four members of a Canadian family. AGU is a lysosomal storage disease in which asparagine-linked glycopeptides accumulate to particularly high concentrations in liver, spleen and thyroid of affected individuals. A lesser accumulation of these glycopeptides is seen in the kidney and brain, and they are also excreted in the urine.

Psychopharmacogenetic aspects of Prader-Willi syndrome.

The study of genes, drugs, and behavior in three male adolescents with Prader-Willi syndrome (PWS) revealed a clinical profile that raises questions about the indications for neuroleptic and appetite-suppressing medications in this condition. Evidence of the inadvisability of neuroleptic medication and of the pathophysiology of PWS has led to a remarkable control of violent outbursts and hyperphagia by carbamazepine in one patient afflicted with both PWS and Klinefelter's syndrome. Testosterone and behavioral therapy proved to be useful in the management of two patients.

Enzymatic fluorometric assay for plasma pyridoxal 5'-phosphate.

An enzymatic fluorometric assay to quantitate plasma pyridoxal 5'-phosphate (PLP) is described. PLP is preincubated for 30 min with purified tyrosine decarboxylase apoenzyme (TDA) in acetate buffer and is then incubated with L-tyrosine for 60 min. The decarboxylated metabolite, tyramine, is extracted into ethyl acetate, air dried, dissolved in borate buffer and reacted with fluorescamine to form a fluorophor (395/475 nm).

The genesis of atherosclerosis in pediatric age-group.

The three forms of origin of the atherosclerotic plaque of adults, that is, the fatty streaks, gelatinous elevations, and microthrombi, all occur in arteries of normal infants and children. Some of these may become arrested or regress, but many progress to the prominent lesions that precipitate various clinical catastrophies. The aim of modern medicine is to modify or eliminate many of the factors known to advance the atherosclerotic process and thus decrease the incidence of this disease, which ranks highest on the list of causes of morbidity and mortality in the Western world.

Mentally retarded adolescent sex offenders. A survey and pilot study.

There is not a great deal of empirical research on adolescent sex offenders and even less on mentally retarded adolescent sex offenders. This study provides some preliminary data in this area. Results of a survey of the extent and types of sexual problems evident amongst groups of mentally retarded and intellectually normal adolescents (N = 196), seen at an assessment and treatment centre in southwestern Ontario during a 14 month period is presented.

The lead program at CPRI.

A lead (Pb) screening program in operation at CPRI in London, Ontario, since 1977 involves simultaneous measurement of blood Pb and erythrocyte protoporphyrin (EP) in a randomized population of physically and/or mentally handicapped children and adolescents on admission, discharge and during outpatient visits. This 11-year study has yielded a large database for computerized evaluation. Based upon log normal transformation of data obtained from the admission and outpatient groups, the normal curve yielded a mean and standard deviation (SD) for blood Pb of 0.

The preparation of rat liver lysosome membranes. Several membrane proteins contain complex oligosaccharides.

Lysosome membranes were isolated, and membrane proteins and glycoproteins were characterized by electrophoresis and lectin probes of nitrocellulose blots. Rat liver lysosomes were isolated on a discontinuous metrizamide gradient and characterized by subcellular marker enzymes. Lysosomes were lysed by hypotonic freeze-thaw shock and membranes were isolated.

The hyperornithinemia, hyperammonemia, homocitrullinuria syndrome: an ornithine transport defect remediable with ornithine supplements.

The primary defect in patients presenting with a history of protein intolerance, mental retardation, and epilepsy of variable degree, with the unique triad of hyperornithinemia, hyperammonemia, and homocitrullinuria (the HHH syndrome) has been postulated to be a defect in translocation of ornithine into the mitochondria. In a 12-year-old boy with the HHH syndrome, the hyperammonemia observed following a protein load was prevented when the same load was given orally with a 1 mmol/kg of ornithine-HCl. At a dosage level of 0.

Cytogenetic practice in a mental retardation clinic.

Chromosome abnormalities are known to be associated with a wide variety of psychiatric disorders varying from severe mental retardation to aberrant social behaviour. Principles and methods used in contemporary cytogenetic laboratories are discussed and an attempt is made to illustrate how the integration of these techniques can be of considerable value for diagnostic and genetic counselling purposes.