Longitudinal magnetic resonance imaging study of rhesus monkey brain development.

To examine early brain development, T1-weighted structural MRI scans of seven rhesus monkeys (Macaca mulatta) were obtained longitudinally between the ages of 1 week and 4 years at 12 age points. Total brain volume, calculated at each age point, increased significantly, by 56%, between 1 week and 4 years. The greatest increase of 22% occurred between 1 week and 1 month, followed by further significant increases between 1 and 2 months, and 3 and 4 months. Gradually smaller increases continued up to 3 years with no further significant changes thereafter. A robust maturation of white matter occurred between 1 week, at which the only easily identifiable fibre tracts were internal capsule and optic radiations, and 3 months, at which most large fibre tracts were visible; only at this age reproducible measurements were possible for all cases. White matter volume increased by 126% between 3 months and 4 years, with the biggest increase between 3 and 4 months (32%) followed by smaller but significant increases up to 4 years. The macaque brain development parallels that of humans by reaching the maximum in total brain volume around the age of sexual maturity (in macaques 3-4 years) and by the increases in white matter continuing beyond this age. The most rapid growth in both total brain volume and white matter from birth to approximately 4 months is consistent with the emergence of various cognitive abilities in macaques at that age.

[Dowling-Meara Epidermolysis bullosa herpetiformis]. / Epidermolysis bullosa herpetiformis Dowling Meara.

A new born girl perinatally suffered from a generalized blistering disease of the skin. By means of histological, in particular ultrastructural methods the diagnosis of Epidermolysis bullosa herpetiformis Dowling Meara could be confirmed in the first weeks of life. The Dowling Meara type is one of the epidermal variants of this group of inherited blistering diseases with a relative benign course. The early diagnosis is helpful in the prognostic assessment of the disease and in the medical and genetic advice for the parents.

Plasma digoxin levels in anuric patients and normal subjects taking digitoxin.

Plasma digoxin suspected to be elevated in anuric patients taking digitoxin was determined by radioimmunoassay in 15 anuric patients and 15 normal persons subjected to 0.1 mg digitoxin therapy per day. All plasma digoxin values from the anuric patients and the normal subjects were far below the lower limit of the therapeutic range of plasma digoxin. There existed no difference between the digoxin values determined in anuric patients and subjects with normal renal function; in both groups there was a scatter of digoxin values about the cross reaction line between digitoxin and digoxin antibody. It is concluded from the results that digoxin retention in anuric patients taking digitoxin plays an insignificant role; thus, the pharmacological effect is mediated by digitoxin itself.

Intestinal recycling and substitution of haemofiltrate in dogs.

Haemofiltrate was administered into the duodenum of 5 ambulatory dogs through an implanted silastic catheter at a rate of 5-10 ml/min. None of the dogs presented signs of discomfort or suffered from regurgitation or diarrhoea. All 5 dogs had solid stools, enhanced diuresis and no change in body weight over a time period of 8 hours. Filtration rates between 5 and 10 ml/min were obtained in 7 dogs after connecting an Amicon in-line Ultrafilter with an external a.v. shunt. The intestinal recycling rate via the duodenal tube as a rule was 2 ml/min lower than the free flow ultrafiltration. Recirculation of autologous haemofiltrate in 5 uraemic dogs indicated unselective reabsorption of all electrolytes and small molecules. In 5 experiments with intestinal substitution of ultrafiltrate by a potassium-free Ringer's lactate solution, correction of acidosis and decrease in plasma potassium, creatinine and BUN was achieved.