Biomedical subjects

J Rudel

Publications and source records attributed to J Rudel.

5 recordsLinked to original sources

PubMed1994

[Specific in situ labeling of apoptosis shows different rates of programmed cell death in non-Hodgkin lymphomas].

Two new techniques were used to quantify cell death (i.e. DNA fragmentation) in situ: (1) 3' overhangs of the fragmented DNA were end labelled with biotin-7-dATP and TdT (peroxidase/DAB). (2) In situ nick translation (ISNT) was performed with DNA polymerase 1 and biotin-7-dATP, to label single strand segments of DNA (peroxidase/DAB). Both methods were tested to be negative in ischemic and tumor necrosis, and negative for mitotic figures. In 26 centroblastic Non Hodgkin lymphomas (CB) (monomorphous subtype [n = 9], polymorphous subtype [n = 7], secondary [n = 10]), 14 chronic lymphocytic leukemias and two immunocytomas these methods were employed to quantify the rate of cell death. ISNT proved to be more sensitive than end labelling. By ISNT, CB had a mean cell death rate of 250/10HPF (monomorphous type: 429/10HPF, polymorphous type: 222/10HPF, secondary: 111/10HPF). CLL showed a significantly lower rate (28/10HPF). These data suggest, that the low rate of cell turnover in CLL is indicated by a low rate of cell proliferation and a low rate of programmed cell death. In CB the high proliferation rate was accompanied by a high level of cell death. In CB/monomorphous a high turnover state with a very high proliferation and cell death rate was found, whereas CB/polymorphous represents an expansive state as indicated by a lower rate of cell death. CB/secondary showed almost no programmed cell death and therefore was interpreted as a high expansive state neoplasia.

Apoptosis↗

PubMed1987

[Morphology of diabetic neuropathy].

The morphological findings in peripheral nerves in diabetic subjects are reviewed. Diabetes is probably the most frequent cause of neuropathy. However it does not constitute a single nosological entity but is comprised of a variety of clinical and morphological changes. These are considered to be the consequences of metabolic derangements resulting from chronic hyperglycemia. Distal symmetrical neuropathies, which are most common, are characterized by axonal degeneration and segmental demyelination with loss of nerve fibres and fibrosis. Remyelination and axonal sprouting occur. Microvascular changes consist of thickening and hyalinization of the walls of the vessels. On electron microscopy these vessels appear thickened and show reduplication of the basal lamina that surrounds the endothelial cells and pericytes. The morphological bases of proximal symmetrical motor neuropathy, as well as of focal and multifocal neuropathies are briefly described. The synopsis of current knowledge can be helpful in diagnosis and differential diagnosis of disorders of the peripheral nervous system.

Axons↗

PubMed1984

[Histochemical, biochemical and microelectrophoretic studies of gamma-glutamyl transpeptidase in the central nervous system of the rat].

The activity of the enzyme gamma-glutamyltranspeptidase (GGT, E.C. 2.3.2.1) was studied in brains of Wistar rats at different stages of pre- and postnatal development. In brain homogenates the activity was lowest at day 20 of pregnancy. After birth it increased slightly up to day 10 of postnatal life, than a drastic increase could be observed until day 30, where the enzyme activity reaches a plateau, which was constant over the whole lifetime. At day 15 of pregnancy histochemical examination revealed enzyme activities in brain capillaries and the leptomeninx. No or very low activities were found in the choroid plexus and in the ependyma. The GGT activity continuously increased over the following time of pregnancy and postnatal development. At day 5 of postnatal development additionally to activities in the leptomeninx, brain capillaries, choroid plexus and ependyma the enzyme could also be observed in undifferentiated cells of the subependymal periventricular layer of the telencephalon. Microdiscelectrophoretical separation of Triton X-100 homogenate extracts of microdissected cells from the subependymal layer and the ependyma or the choroid plexus, resp., revealed only one enzyme band of GGT.

Animals↗

PubMed1984

[Use of analytic microelectrophoresis in clinical and experimental pathology].

A short survey is given about the application of microelectrophoresis in clinical and experimental pathology. There are several fields in which microelectrophoresis in combination with enzyme histochemistry offers new possibilities in diagnosis, especially in cytology, liver biopsy and tumor pathology. Some difficulties and own experiences with the application of microelectrophoresis are shortly discussed.

Animals↗

PubMed1982

[Agyria--a clinico-pathological study (author's transl)].

Agyria is an extremely rare malformation of the brain caused by an arrest of neuronal migration towards the cortex. A case of nearly complete agyria is presented in a 2 8/12 year-old boy. The autopsy revealed complete absence of cerebral convolutions in the frontal, parietal and occipital lobes of both hemispheres and discrete convolutions in the temporal lobes. The cortex reached up to 22 mm and the central white matter was very thin, occipitally up to 2 mm. Additionally, hydrocephalus internus was observed. Clinical and pathoanatomical findings are presented and compared with other data published in the literature. The results are discussed in relation to a possible pathogenetic mechanism leading to this cerebral malformation.

Autopsy↗