Alfons Cornelis

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We examined liver biopsies from 4 patients with the infantile form of Refsum disease. No peroxisomes were visualized by light microscopy after cytochemical staining for catalase, a marker enzyme for this organelle. Absence of peroxisomes was confirmed by electron microscopy in 3 patients; in the 4th patient we observed organelles of peculiar size and(More)
In an autopsy study of 37 infants who suffered from hyaline membrane disease (HMD), two distinct patterns of pulmonary lesions could be defined. One pattern, characterized by marked interstitial fibrosis in the absence of airway abnormalities, was labelled 'interstitial-type' histology. A second type, labelled 'bronchiolar-type' histology, showed marked(More)
Three patients affected by infantile Refsum disease are described with mental retardation, minor facial dysmorphia, chorioretinopathy, sensorineural hearing deficit, hepatomegaly, failure to thrive and hypocholesterolaemia. Initially, only an accumulation of phytanic acid was thought to be present. More recent findings showed a biochemical profile very(More)
Hepatocellular peroxisomes stained for catalase activity have different electron densities. When measured by scanning transmission electron microscopy, density is inversely linear to diameter. We investigated whether this phenomenon is the result of a staining artifact that reflects more efficient diffusion of substrate into smaller peroxisomes (higher(More)
The number, intracellular distribution, and staining characteristics of human hepatocellular peroxisomes that had been made visible by cytochemical staining for catalase were evaluated in biopsies from 75 patients with hepatic, inflammatory, or malignant disease and ten normal individuals. Intensity of staining was found to be proportional to enzymatic(More)
In ethanol-water mixtures (90:10), the gramicidin dimer binds Na+ cations at well-defined sites, with a binding constant K = 4 M-1. Partial desolvation of Na+ occurs upon binding, as judged from the magnitude of the quadrupolar coupling constant (1.7 MHz) for bound sodium. The binding sites are identified with the outer sites flanking the channel entrances.(More)
We present autopsy studies in 4 unrelated fetuses with the lethal multiple pterygium syndrome (LMPS) with special emphasis on the neuromuscular system. The data suggest that LMPS combines the manifestations of a jugular lymphatic obstruction sequence with those of an early severe fetal akinesia sequence. The jugular lymphatic obstruction sequence with(More)
This paper describes our work concerning densitometry and morphometry of subcellular structures in thin sections. The techniques of automatic image analysis were applied to light and electron microscopic observations of enzymatically stained lysosomes, renal brush borders and mitochondria (in human and rat kidney) and peroxisomes (in human liver). To obtain(More)
Software was developed for the acquisition, segmentation and analysis of microscopic OD-images on a VICOM digital image processor, extended with a VISIOMORPH morphoprocessor board. The delineation algorithms for peroxisomes, lysosomes, and nuclei in liver, kidney, and adrenal gland sections start by thresholding the difference between the original image and(More)