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S Kornguth

Publications and source records attributed to S Kornguth.

25 records · Page 2Linked to original sources

Defect of cerebellar Purkinje cell histogenesis associated with type I and type II renal cystic disease.

The cerebellar vermises from a 1 day old child who died with cystic dysplastic kidneys (Potter Type II) and from a 28 day old who died with infantile polycystic kidneys (Potter Type I) were studied by the Golgi silver method and electron microscopical procedures. Golgi stains showed that Purkinje cells from both cases had the following abnormal characteristics: (1) they retained perikaryal processes even at 37-42 weeks after conception although these processes are normally absent from the cerebellar vermis after 34 weeks of gestation; (2) The Purkinje cell dendrites had dilations at their numerous branchpoints. Ultrastructural studies indicated that climbing fibers remained in contact with the perikaryon of the Purkinje cell in both cases although they are not normally present on the perikaryon after 33 weeks gestation. The 1 day old child (Type II) had unusual synaptic structures of the dyad and serial type. The concurrence of cerebellar and kidney cell maldevelopment in this and a variety of other conditions suggests that there may be a pathogenetic and causal relationship between the two.

Cerebellum↗

Isolation of dendrodendritic synapses from swine olfactory bulbs.

Dendrodendritic synapses from swine olfactory bulbs were isolated by homogenization of the gray layer, followed by centrifugation at 1000 X g. Centrifugation of the supernatant at 10,000 X g revealed that all dendrodendritic synapses had pelleted at 1000 X g. The upper portion of the 1000 X g pellet was further purified in a discontinuous sucrose gradient, and each resultant fraction was examined by electron microscopy. The dendrodendritic synapses band below the 1.2-1.4 M sucrose interface, appear to be minimally contaminated with other membranous elements, and have retained their adhesions. The banding pattern and relative amounts of proteins from dendrodendritic synaptosomes were very similar to those of axonal synaptosomes as determined by electrophoresis on polyacrylamide gels containing sodium dodecyl sulfate (SDS) and 8 M urea.

Animals↗

Crystals, paracrystals, and rigid tubules in multiple sclerotic brain and spinal fluid.

Brain and spinal fluid were obtained post mortem from an individual with multiple sclerosis who died following carbon monoxide inhalation. Electron microscopic examination of the plaque region revealed a crystalline structure (repeat unit 380 to 410 A) within rough endoplasmic reticulum of astrocytes, a paracrystal (160 to 220 A) within the cytoplasm of astrocytes, and rigid tubules (outer diameter 320 to 450 A) within a cell in the lumen of a capillary. The paracrystal was enclosed by the glial fibrils. A second crystalline material was observed within cells in the 15,000 X g pellet from spinal fluid. The ultrastructural pattern of this second crystal was generated by three sets of parallel lines; a given set was intersected by the other two sets. The crystal had only two different repeat units (410 to 450 A; 310 to 350 A) since the smaller dimension was common for two sets of lines. The two crystals were large; the one in astrocytes had a length of 52,000 A and that in spinal fluid sediment was 62,000 A. These structures were observed in the one multiple sclerotic brain obtained at autopsy but were not detected in multiple sclerotic brains that had been frozen for extended periods. Plaque regions and grossly normal white matter were homogenized and the 1000 X g supernatant of this material was fractionated in a continuous CsCl-sucrose density gradient. Long tubules (320 to 500 A diameter) were observed in the 1.24 to 1.26 density region. The major proteins of the 1.24 to 1.26 fraction had molecular weights clustered at 40,000 to 45,000, 88,000 to 130,000, and 300,000.

Astrocytes↗

Glioblastoma multiforme: MR imaging at 1.5 and 9.4 T after injection of polylysine-DTPA-Gd in rats.

Polylysine-DTPA-Gd, a new MR contrast agent, was injected into the aorta of rats 7 days after C6 glioblastoma was implanted in their brains; MR imaging was performed 3 days later. The imaging was done at two field strengths: (1) 1.5 T with a 3-mm slice thickness and in-plane resolutions of 600 microns and (2) 9.4 T with a 125- or 500-microns slice thickness and in-plane resolutions of 95 microns. In animals injected with polylysine-DTPA-Gd (1 microgram or more per rat), the T1-weighted images and mixed T1, T2 images of the C6 glioblastoma revealed a higher signal intensity at the marginal region between tumor and normal brain than that seen in surrounding normal brain. The central tumor region had a low signal intensity. The concentration of Gd in the C6 glioblastoma, after injection of 1 microgram polylysine-DTPA-Gd per rat, was calculated to be 0.14 mumol/l. The central tumor region also had a low signal intensity in animals that were not injected with the contrast agent, but the margin between tumor and normal brain was resolved poorly, if at all. The polylysine-DTPA-Gd revealed the microvasculature of the C6 glioblastoma in the 125-micron-thick slices obtained at 9.4 T. This is the first study to reveal the utility of the 9.4-T MR imager for examination of glioblastomas in situ and to demonstrate the utility of polylysine-DTPA-Gd as a contrast agent for the definition of the margin between glioblastoma and normal brain tissue.

Animals↗