We present brain MR images in three patients with neonatal-onset hyperammonemic encephalopathy resulting from urea-cycle disorders (two sisters with deficiency of the carbamyl phosphate synthetase I reaction step and one boy with an ornithine transcarbamylase deficiency). MR imaging revealed almost identical findings of injury to the bilateral lentiform nuclei and the deep sulci of the insular ...

AIMS Data on recovery from hormonal and metabolic sequelae of alcoholism in strictly controlled alcohol abstinence are mainly restricted to short-term abstention. Our previous findings of persistently decreased plasma and urinary urea concentrations in long-term abstinent alcoholics prompted us to further elucidate this unexplained phenomenon. METHODS The response of circulating urea cycle me...

Mammals express two isoforms of arginase, designated types I and II. Arginase I is a component of the urea cycle, and inherited defects in arginase I have deleterious consequences in humans. In contrast, the physiologic role of arginase II has not been defined, and no deficiencies in arginase II have been identified in humans. Mice with a disruption in the arginase II gene were created to inves...

Most patients with urea cycle disorders who present as neonates, do so with deteriorating feeding, drowsiness and tachypnoea, following a short initial period when they appear well. The plasma ammonia should be measured at the same time as the septic screen in such patients. Ammonia levels above 200 micromol/l are usually caused by inherited metabolic diseases and it is essential to make a diag...

Accumulation of ammonia in body tissues most commonly occurs in hepatic failure. However, it may also result from a specific deficiency of an enzyme of the urea cycle (Fig., 1). Severe hyperammonaemia has been reported with deficiencies of carbamyl phosphate synthetase (Freeman et al., 1964) and ornithine transcarbamylase (Russell et al., 1962; Levin and Russell, 1967). Some increase in blood a...

Accumulation of ammonia in body tissues most commonly occurs in hepatic failure. However, it may also result from a specific deficiency of an enzyme of the urea cycle (Fig., 1). Severe hyperammonaemia has been reported with deficiencies of carbamyl phosphate synthetase (Freeman et al., 1964) and ornithine transcarbamylase (Russell et al., 1962; Levin and Russell, 1967). Some increase in blood a...

RATIONALE. With no effective clearance system for ammonia, levels increase rapidly, resulting in cerebral edema with severe neurologic compromise. Dialysis is the only means of rapid removal of ammonia from blood in acute neonatal hyperammonemia, and hemodialysis is preferred over peritoneal dialysis because it is much more effective. If hemodialysis is not available, hemofiltration can be used...

Convention terminology. There follows a compilation of numerical abnormalities of chromosome constitution, again in order 1 to 22, X and Y. There is a table of syndromes associated with breakage syndromes. Associations of chromosome anomalies and cancer cell lines have been excluded. The preface contains seven tables, listing chromosome involved in polymorphisms, breakage, and aneuploidy syndro...

A 49-year-old woman with intellectual disability and a food preference for fried chicken entered nursing home. After home diet, she developed episodic attacks of hyperammonemic encephalopathy. Her characteristic the negative results brain liver imaging studies suggested urea cycle disorder. high plasma citrulline level on amino acid analysis genetic test citrine gene confirmed deficiency (adult...