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Biomedical subjects

K Schwechheimer

Publications and source records attributed to K Schwechheimer.

At least 73 records · Page 4Linked to original sources

Hallervorden-Spatz syndrome restricted to the pallidal nuclei.

The case history is presented of a man who died at the age of 38 years and had been suffering from severe torsion dystonia and a hypokinetic-rigid motor disturbance since the age of 10. The pathological findings were isolated pallidal degeneration with demyelination and moderate neuronal loss, iron pigment accumulation and spheroid bodies in both pallidal nuclei. In addition the zona reticularis of the substantia nigra was hypoplastic and not affected. The red nucleus, the dentate nucleus and the zona reticularis of the substantia nigra showed iron depigmentation. The rare condition of non-familial Hallervorden-Spatz syndrome, without involvement of the zona reticularis and the cerebral cortex, was considered to be the diagnosis.

Adult↗

Lectin-binding spectra in the hyperplastic human tonsil. Effect of formalin fixation and paraffin embedding on lectin affinity of tissue components.

In order to determine the effect of routine fixation on the lectin affinity of tissue structures, we used unconjugated lectins and an indirect immunoalkaline-phosphatase method for frozen sections, and the peroxidase-anti-peroxidase method for paraffin-embedded, formalin-fixed tissue sections. Fourteen hyperplastic human tonsils were used, and the results of the binding spectra of each lectin were compared. In general, the binding spectrum detected in the paraffin sections was part of the broader range of affinity obtained in the frozen sections. The lectin receptors on the cell surface were especially affected by formalin fixation. On the other hand, the paraffin sections, because of their superior morphology, showed a better localization of the cytoplasmic reaction product and discriminated the cell types more accurately. Thus, the two tissue preparations are rather complementary. In the tonsil peanut agglutinin (PNA) and periodic acid/Concanavalin A (PA/Con A) proved to be suitable tools for distinguishing exactly between the crypt and the surface epithelium. Ulex europaeus agglutinin I (UEA) is a reliable endothelial marker with a strong affinity to the crypt epithelium. In the frozen sections, PNA regularly stained follicular-centre cells on their cell surface. PNA, Helix pomatia agglutinin (HPA), soybean agglutinin (SBA) and Con A stained the histiocytic population, especially PNA which additionally stained an "asteroid" histiocyte. This cell probably corresponds to the antigen-presenting histiocyte of the T-system.

Alkaline Phosphatase↗

Lectin target cells in human central nervous system and the pituitary gland.

Peanut lectin (PNL), Concanavalin A (Con A) and Ulex europaeus lectin I (Ulex) were chosen to map their binding sites in different regions of formalin fixed and paraffin embedded human central nervous system tissue and pituitary gland tissues. An extended PaP method was used for PNL and Ulex, whereas a direct peroxidase technique was employed for Con A. In astrocytes, the cytoplasm as well as the delicate processes were stained by PNL and Con A; the most conspicuous binding of PNL was seen in the ependymal cells and on the surface of plexus epithelial cells; in the anterior part of the pituitary gland a selective population was PNL positive. Intracytoplasmic Con A acceptors could be demonstrated in neurons, in ependymal cells, and in plexus epithelial cells. Intracytoplasmic Con A receptors were finely granular in astrocytes, oligodendrocytes, and in some cells in the pituitary gland. Ulex binding was restricted to the vascular endothelial cells and a selective population of cells in the pituitary gland. Our results suggest that lectins may be good tools for the evaluation of their respective target cells in the central nervous system and in the pituitary gland.

Arachis↗

Lymphoepithelial carcinoma (Schmincke type) as a derivate of the tonsillar crypt epithelium.

Ten tumours of tonsillar or epipharyngeal localization showing the histological picture of "lymphoepithelial carcinoma" (Schmincke 1921) were examined immunohistochemically using Peanut lectin, Ulex europaeus lectin-I and an antiserum to S-100 protein. The findings suggest a close relationship of this type of carcinoma to the normal tonsillar crypt epithelium. The majority of tumour cells are UEA-I-positive and PNL-negative, as is the crypt epithelium, while oral mucosa is both PNL- and to a lesser extent UEA-I-reactive. Tumour areas expressing this pattern contain a large number of asteroid-shaped PNL-positive histiocytes and arachnoid-shaped histiocytes reacting with anti-S-100 protein; both cell types being probably identical and representing typical elements of the normal tonsillar crypt epithelium. Consequently, the WHO-term "nasopharyngeal carcinoma, undifferentiated type" seems to be inadequate for this type of tumour.

Carcinoma, Squamous Cell↗

Concanavalin A binding and neuronal differentiation. A light microscopic study on neuronal tumours.

Concanavalin A (Con A) acceptors have been demonstrated in large differentiated neurons in a previous paper. In order to elucidate the correlation between Con A binding in normal and neoplastic neurons and lectin binding dependence upon the differentiation grade, 26 tumours of the neuronal series were examined using formalin fixed and paraffin embedded biopsy specimen. The neoplasms included 3 gangliocytomas, 7 gangliogliomas, 1 central neuroblastoma, 11 medulloblastomas, 2 retinoblastomas, and 2 sympathicoblastomas. Well differentiated neurons in gangliocytomas and gangliogliomas expressed a high intracytoplasmic Con A acceptor density comparable to the feature in large non-neoplastic neurons. Less differentiated neurons and neuroblasts showed a weak perinuclear fine granular binding or an absolute lack of binding molecules, respectively. Our results suggest that in a variety of tumours, Concanavalin A receptor density in neurons depends upon the degree of differentiation of the cell. Well differentiated cells have a higher density than poorly differentiated neoplastic neurons.

Adolescent↗

Concanavalin A target cells in human brain tumours.

Using a lectin-peroxidase method, Concanavalin A binding was examined on formalin-fixed paraffin-embedded biopsy specimens (n = 143) of the most frequent central nervous system tumours. The brain tumours included oligodendrogliomas, astrocytomas, glioblastomas, ependymomas, neurinomas, meningiomas, medulloblastomas and plexus papillomas. In oligodendroglioma cells, only a weak granular intracytoplasmic staining was observed. The astrocytomas showed a strong reaction in fibrillary astrocytes and in tumour areas undergoing small cystic degeneration. Staining of protoplasmic astrocytes was weaker; pilocytic astrocytes demonstrated poor perinuclear staining. Intracytoplasmic Con A binding in gemistocytic astrocytes was distinct but inconstant and rather diffuse. In the glioblastomas the lymphocyte-like small astrocytes were negative. Giant multinucleated astrocytes stained strongly. In ependymomas no or at most a weak perinuclear reaction was observed, whereas the acceptor density was as high as in the normal ependymocytes in areas where the tumour was capable of producing organotypical structures. Plexus papillomas showed a strong intracytoplasmic staining comparable to the normal plexus epithelial cell. This feature was preserved in the malignant variants. In general, meningiomas and neurinomas were negative. Xanthomatous-degenerated meningioma cells, however, showed a distinct to strong intracytoplasmic staining. This feature was characteristic for the xanthomatous subtype of meningiomas. Granular cells with strong intracytoplasmic Con A staining often occurred at the border of fibrillary to reticular differentiated areas of neurinomas. Medulloblastomas were completely negative. Our results indicate that Con A binding to human brain tumours is specific and rather cytotypical than histotypical . The Con A acceptor density is probably related to the grade of differentiation. Lectin mapping of tumours leads to cytotypical binding patterns which may contribute to the differential diagnosis of neoplasias.

Astrocytoma↗

Attachment of vimentin filaments to desmosomal plaques in human meningiomal cells and arachnoidal tissue.

Desmosomal proteins are co-expressed with intermediate-sized filaments (IF) of the cytokeratin type in epithelial cells, and these IF are firmly attached to the desmosomal plaque. In meningiomal and certain arachnoidal cells, however, vimentin IF are attached to desmosomal plaques. Meningiomas obtained after surgery, arachnoid "membranes", and arachnoid granulations at autopsy, as well as meningiomal cells grown in short-term culture have been examined by single and double immunofluorescence and immunoelectron microscopy using antibodies to desmoplakins, vimentin, cytokeratins, glial filament protein, neurofilament protein, and procollagen. In addition, two-dimensional gel electrophoresis of the cytoskeletal proteins has been performed. Using all of these techniques, vimentin was the only IF protein that was detected in significant amounts. The junctions morphologically resembling desmosomes of epithelial cells have been identified as true desmosomes by antibodies specific for desmoplakins and they provided the membrane attachment sites for the vimentin IF. These findings show that anchorage of IF to the cell surface at desmosomal plaques is not restricted to cytokeratin IF as in epithelial cells and desmin IF as in cardiac myocytes, suggesting that binding to desmosomes and hemidesmosomes is a more common feature of IF organization. The co-expression of desmosomal proteins and IF of the vimentin type only defines a new class of cell ("desmofibrocyte") and may also provide an important histodiagnostic criterion.

Arachnoid↗

Vimentin filament-desmosome cytoskeleton of diverse types of human meningiomas. A distinctive diagnostic feature.

Ten human meningiomas of different histologic subtypes (endotheliomatous, transitional, fibroblastic, and angioblastic) were examined for the expression of intermediate-sized filaments (IF) and desmosomal plaque proteins (desmoplakins I and II), using immunofluorescence and immunoelectron microscopy. All meningiomas gave a strong positive reaction for vimentin as well as for desmoplakins. IF of the cytokeratin type, desmin IF, and glial filaments were not detected in any of these tumors. The exclusive expression of vimentin in these tumors was confirmed by two-dimensional gel electrophoresis and immunoblot analysis of cytoskeletal proteins obtained after microdissection of well-defined tumor areas. Ultrastructural immunolocalization showed that, in the various tumors, vimentin IF were attached to the desmosomal plaques. With respect to the markers examined, all of the diverse types of meningiomas reacted like their putative non-neoplastic counterparts, i.e., arachnoidal cells. Our results indicate that the different histologic subtypes of meningiomas are derived from cells of the arachnoidal layer. The exclusive expression of vimentin-type IF in combination with desmoplakins is very unusual and so far seems unique to arachnoidal and meningioma cells. We consider this unusual combination, i.e., vimentin IF and desmoplakin plaques, to be a diagnostic feature for meningiomas, and we propose that the cytoskeletal property be used in differential diagnosis of intracranial tumors.

Cytoskeletal Proteins↗

Morphological feedback effect on neurons of the nucl. arcuatus (sive infundibularis) and nucl. subventricularis hypothalami due to gonadal atrophy.

We have correlated the light-microscopic features in the unmyelinated hypothalamus with gonadal atrophy in 15 women of 30-111 years of age and in 7 men between 29 and 82 years. In the postmenstrual cases there is a distinct concordance of gonadal atrophy and the manifestation of nucleolar changes (augmentation, multiplication and vacuolization) in many nerve cells of the arcuate and subventricular nuclei. In younger, still fertile women this nucleolar finding was seen only rarely and sporadically, was limited to the arcuate nucleus and was absent in the subventricular nucleus. We interpret this nucleolar finding as a feedback effect. In man, too, this coincidence is obvious with age and in gonadal atrophy, with fewer nucleolar changes in old age than are seen in women. This difference is probably caused by a more rapid drop of the estradiol than of the testosterone level. - The hypertrophy of the subventricular nucleus (Sheehan and Kovacs) was also observed in our postmenstrual cases.

Adult↗

Emphasis on peanut lectin as a marker for granular cells.

Peanut lectin (PNL) binding to a total of 13 granular cell tumours was examined by means of the peroxidase antiperoxidase technique. The tumours included six tumourettes of the neurohypophysis, one malignant granular cell tumour of the brain, and six peripheral tumours of distinct locations. Every tumour studied showed intracytoplasmic fine granular PNL binding; after pretreatment with neuraminidase, the weakly positive reaction was enhanced to a great extent. In all tumours simultaneous examination for the detection of lysozyme and glial fibrillary acidic protein (GFAP) was also carried out. Lysozyme was negative in all cases, whereas GFAP expression could be demonstrated at the periphery of the malignant granular cell tumour of the brain. The data presented clearly demonstrate that PNL can be used as a histochemical marker for granular cells regardless of their location. The fact that the presence of lysozyme could not be proved does not support the view of a histiocytic origin for granular cells, whereas the expression of GFAP in some immature granular cells of the brain tumour examined is considered to be an argument in favor of its glial origin.

Adult↗

Immunohistochemical localization of peanut lectin binding sites on human brain tumors as determined by peroxidase-antiperoxidase technique in paraffin sections.

Peroxidase-antiperoxidase (PAP) technique was selected for visualizing the binding of peanut lectin (PNL) to the most frequent human brain tumors. The randomly selected material included neoplasms of neuroectodermal and mesenchymal origin. We employed 1--5 micrometers of routinely processed and paraffin-embedded tissues. PNL receptors were detected to a variable extent on the cell surface of astrocytoma, glioblastoma multiforme, oligodendroglioma, ependymoma, meningotheliomatous meningeoma, and plexus papilloma. In gliomas as increase in malignancy seems to be associated with a decrease in PNL binding. Except for the plexus papillomas, neuraminidase pretreatment had neither a qualitative nor a quantitative influence on the binding behavior of PNL. Intracellular PNL receptors could be detected in "granular cells" and in the perinuclear region of malignant gliomas.

Arachis↗

Brain metastases in malignant fibrous mesothelioma. Case report and review of the literature.

A malignant fibrous mesothelioma is reported in a man of 70, arising from the left pleura with widespread metastases in the regional lymph nodes, diaphragm, chest wall, adrenal glands, and brain. Asbestos bodies were not found. Histologically, the primary tumor consisted of interlacing bundles of spindle-shaped malignant cells with a considerable number of mitoses. In the brain two large metastases occurred. Macroscopically, the occipital metastasis looked like an intracranial hemorrhage. Microscopically, the metastases mimicked the pattern of a glioblastoma multiforme. The present case is discussed against the background of the pertinent literature.

Aged↗

Arteriovenous angioma of the vein of Galen causing cardiac failure in the neonate. Report on clinical and pathological findings in two cases.

Clinical details of two cases of arteriovenous angioma of the vein of Galen are presented. In one case a diffuse meningo-cerebral angiodysplasia was found at necropsy. Due to a large arteriovenous shunt both cases became apparent in the neonatal period by progressive and fatal heart failure as the main clinical feature. Increased head circumference and a loud cranial bruit suggested the final diagnosis. Improvement of diagnostic work-up by computerized axial tomography and two-dimensional ultrasound with less discomfort to the patient is emphasized.

Brain Neoplasms↗

Interaction of simian virus 40 with human glioma cells.

A human oligo-astrocytoma grade II was successfully grown in tissue culture. Using glial fibrillary acidic protein (GFAP) as an astrocytic marker two main cell types could be differentiated: GFAP-positive astrocytes and GFAP-negative oligodendrocytes. After transformation by SV40 about 90% of the tumor cells expressed SV40 T-antigen as detected by indirect immunofluorescence. The percentage of viral capsid (V-)antigen was much lower; it was only found in oligodendrocytes. Six passages after transformation the oligodendrocytes were eliminated due to lytic viral infection. By double immunofluorescence with anti-GFAP as a cell marker and anti-T as a viral marker the remaining cell type was identified as transformed astrocytes. These data suggest a different susceptibility of oligodendrocytes and astrocytes, respectively, to transformation by SV40. While the oligodendrocytes permit the production of infectious virus, the astrocytes are more sensitive to transformation. The evident correlation to human progressive multifocal leukoencephalopathy will be discussed.

Antigens, Viral, Tumor↗