Biomedical subjects
Publications and source records attributed to R Stenger.
Syndromes presenting with interstitial radiological signs are often difficult to diagnose aetiologically. Surgical biopsy prevents certain rare cases being neglected notably when there are atypical manifestations. We describe a case of bronchiolitis obliterans with an organising pneumonia which was classical as regards the histology and its response to treatment but unusual as regards the clinical presentation and the aetiology.
At present the classic "kernicterus" has nearly disappeared, but toxic effects of bilirubin, nevertheless, play an important role in the etiology of late neurologic sequelae in VLBW infants. Even in very low concentrations of serum bilirubin CNS damages have to be expected when other metabolic disturbances induce the opening of blood-brain-barrier. Since safe criteria for predicting toxic effects of bilirubin do practically not exist, in VLBW infants with perinatal metabolic disorders early preventive phototherapy is indicated to keep the serum bilirubin level as low as possible. Experimental studies in animals showed brain protective effects of barbiturates apart from enzyme induction.
The transepithelial potential difference of the gastrointestinal mucosa as a diagnostic parameter obtains increasing importance in clinical medicine. Therefore it is necessary to consider methodical aspects of the tPD-measurement under in-vivo conditions. The current paper presents methodical considerations for instance electrode arrangement, positions, composition of the electrolyte electrodes, diffusion potentials, rate of perfusion and unstirred water layer and their influence on the tPD-measurement.
Previous studies indicated that exposure to compression-decompression increases blood-brain barrier (BBB) permeability to vital dyes and antibiotics. This report concerns functional and ultrastructural BBB changes induced by altitude decompression. A 2% trypan blue solution was intravenously injected (4 ml.kg-1) into 29 experimental and 19 control rabbits. Some animals also received horseradish peroxidase. The experimental animals were subjected to 30,000 ft (4.3 psi) for 45 min. Controls were kept at ground level. The animals were sacrificed 90 min postinjection. Gross and microscopic examination and spectrophotometric dye determination revealed significantly greater tracer penetration in experimental brains (mean dye concentration 27.06 +/- 4.42 micrograms.g-1) than in controls (4.52 +/- 1.52 micrograms.g-1). No sex differences were noted. Electron microscopy suggested that the increased BBB permeability was due to transendothelial vesicular transport and, occasionally, to penetration through interendothelial junctions. These observations may have relevance to pharmacotherapy in space and at high altitudes and to the pathogenesis of altitude decompression sickness.