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  • 1
    ISSN: 1433-0458
    Keywords: Schlüsselwörter Cholesteatom ; Perimatrix ; Histologie ; Wachstumsfaktoren ; b-FGF ; Gefäßneubildung ; Key words Cholesteatoma ; Perimatrix ; Histology ; Basic fibroblast growth factor ; Angioneogenesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary The growth of a cholesteatoma requires angioneogenesis in the connective tissue of the perimatrix. Angioneogenesis is also needed for wound healing as a host response to tissue injury. Normal wound repair is conducted through a wide number of growth factors. Basic fibroblast growth factor (b-FGF) plays a pivotal role in wound repair. This cytokine exerts its effects through stimulation of a wide range of target cells. B-FGF is chemotactic and mitogenic for fibroblasts, endothelial cells and keratinocytes. In addition, b-FGF can stimulate the production of collagenase and plasminogen activators to enhance fibroblast proliferation and angioneogenesis. Its necessity for normal wound repair has been confirmed by several workers. Method: In order to demonstrate angioneogenesis in the cholesteatoma perimatrix the distribution of b-FGF as the pivotal cytokine of the process was investigated in the perimatrix of 18 cholesteatoma specimens. Results: B-FGF could be observed in 12 of 18 specimens (66%) in close approximation to histological signs of inflammation and wound healing. Areas with b-FGF also exhibited proliferation of the covering squamous epithelium. Cholesteatoma matrix tissue without inflammation or any sign of wound healing did not express b-FGF (6 of 18). Conclusion: Histological changes and distribution pattern of b-FGF in the perimatrix of cholesteatoma in the present study indicate that the perimatrix cells and substances of the wound healing cascade may play an important role in cholesteatoma development, angiogenesis and growth.
    Notes: Zusammenfassung Entwicklung und Wachstum eines Cholesteatomsackes erfordern Gefäßneubildung in der ernährenden Perimatrix. Im Säugetierorganismus beeinflußt der „basic fibroblast growth factor” (b-FGF) die Angioneogenese bei normalem Größenwachstum und der Wundheilung. Dieses Zytokin wird bei der Wundheilung von Fibroblasten und Makrophagen freigesetzt, Zellen die in großer Zahl in der Perimatrix des Cholesteatoms vorkommen. Der B-FGF wurde bereits im Cholesteatomgewebe untersucht. Bisher ist unklar, wann b-FGF in der Cholesteatomperimatrix nachweisbar wird. Methode und Ergebnisse: Zur Untersuchung wurde der b-FGF in der Perimatrix des Cholesteatomsackes immunhistologisch dargestellt. Zur Auswertung gelangten 18 intraoperativ gewonnene Gewebeproben von klinisch unterschiedlichen Cholesteatomen. Der b-FGF konnte in 12 (66%) der Proben nachgewiesen werden. Dabei wurde b-FGF nicht kontinuierlich exprimiert, sondern war nur in Umgebung von entzündlichem Granulationsgewebe und Wundheilungsvorgängen zu beobachten. Das unmittelbar anliegende Epithel der Matrix zeigte deutliche Hyperproliferationszeichen. In dünner Matrix, ohne erkennbare Invasion von Entzündungszellen, war kein b-FGF nachweisbar. Schlußfolgerung: Die Ergebnisse lassen einen Einfluß von Wundheilungsvorgängen in der Perimatrix auf das Wachstum, die Gefäßneubildung und das Verhalten eines Cholesteatomsackes wahrscheinlich werden.
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  • 2
    ISSN: 1432-2307
    Keywords: Immunohistochemistry ; Pituitary gland ; Pituitary adenomas ; Cytokeratins ; Intermediate filaments
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Ten non-neoplastic pituitary glands and 22 pituitary adenomas producing different hormones were studied by immunofluorescence microscopy as well as peroxidase-antiperoxidase and biotin-avidin techniques on frozen sections and formalin-fixed, paraffin-embedded material using antibodies to cytokeratin, vimentin, GFAP, neurofilament protein and different pituitary hormones. The endocrine cells in non-neoplastic pituitary glands as well as in most pituitary adenomas were cytokeratin-positive. The cytoplasmic cytokeratin distribution patterns of non-neoplastic and tumor cells were similar and typical of the type of hormone produced: GH-producing normal cells showed a paranuclear condensation of cytokeratin-reactive intermediate filaments; this accumulation was even further accentuated in GH-producing adenomas resulting in fibrous bodies (Kovacs and Horvath 1978) decorated by cytokeratin antibodies. Prolactin-producing cells showed a less intense cytoplasmic cytokeratin-specific staining with focal paranuclear accentuation in non-neoplastic as well as in neoplastic glands. ACTH-producing cells in normal pituitary glands as well as in adenomas exhibited a strong and more uniform cytoplasmic cytokeratin staining. The cytokeratin reactivity in glycoprotein hormone-producing cells of non-neoplastic tissue and adenomas was weak. Vimentin and GFAP reactivity was confined to agranular folliculo-stellate cells. The specific and different distribution patterns of cytokeratins in pituitary cells can, therefore, provide an (indirect) indication to the production of a specific hormone if immunocytochemistry fails to demonstrate hormone production.
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  • 3
    ISSN: 1433-8491
    Keywords: Eosinophilic meningoencephalitis ; CSF-cytology ; Helminthic infections ; Allergic-toxic encephalitis ; Eosinophile Meningoencephalitis ; CSF-Cytologie ; Wurmerkrankungen ; Allergisch-toxische Enzephalitis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Berichtet wird über eine akute toxische Schädigung des Gehirns bei einem 43-jährigen Patienten, der 12 Tage vor seinem Tode, nach dem Versiegeln seines Bodens an starken Kopfschmerzen ohne Fieber erkrankte und eine extreme Eosinophilie im Liquor cerebrospinalis zeigte. Eine Übersicht über die mannigfaltige Ätiologie der Liquoreosinophilie wird gegeben.
    Notes: Summary The authors report about a 43-year-old male patient, who suffered from an acute toxic brain injury. Twelve days prior to death, after sealing his floor, he experienced progressively increasing headache without fever; the CSF examination disclosed marked eosinophilia. The clinical and pathomorphological features of his illness are discussed and together with the various possible etiologies of eosinophilia in the CSF.
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  • 4
    ISSN: 1432-0533
    Keywords: Immunohistochemistry ; Folliculo-stellate cells ; Pituitary gland ; Pituitary adenoma ; S-100 protein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Presence and distribution of S-100 protein (S-100), neuron-specific enolase (NSE), cytokeratin polypeptides, glial fibrillary acidic protein (GFAP), vimentin, actin, lysozyme and pituitary hormones (prolactin, hGH, ACTH, β-FSH, β-LH, β-TSH, alpha subunit) in folliculo-stellate cells (FSC) were studied in seven normal human pituitary glands and 28 pituitary adenomas using peroxidase-antiperoxidase and the avidin-biotin immunohistochemical techniques. Approximately 5% of the cells of the adenohypophysis were agranular, non-hormon-producing FSC most of which showed a conspicuous and strong reaction with S-100 antibodies but some were, in addition, GFAP- and vimentin-positive. In contrast to endocrine cells (EC), FSC were not decorated by antibodies to NSE or cytokeratins. In addition to supportive functions, these cells, due to their close special relationship to EC, seem to have transport and other metabolic functions yet to be elucidated. By their S-100 reactivity and their distribution FSC are comparable to glial cells of the central and schwann and satellite cells of the peripheral nervous system (PNS) as well as to supportive cells in neuroendocrine organs and related tumors (e.g., pheochromocytomas, paragangliomas, carcinoids). With one exception, S-100 reactive FSC were not found in pituitary adenomas. The immunohistochemical demonstration of S-100 protein in pituitary tissue is, therefore, a reliable aid in the discrimination between adenomas and normal pituitary tissue, particularly in small and poorly preserved specimens. In one adenoma FSC were found in addition to ACTH-producing tumor cells. This seems to be an extremely rare event suggesting a combination tumor.
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  • 5
    ISSN: 1432-0533
    Keywords: Malignant thymoma ; Carcinomatous meningeosis ; CSF cytology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In a 57-year-old male patient meningitic symptoms occurred. CSF cytology exhibited carcinoma cells, thus establishing the diagnosis of carcinomatous meningeosis. The primary site of the tumor or metastases were not detected intra vitam. The autopsy revealed a malignant thymoma with an exclusive metastatic participation of the leptomeninges except for some few regional lymph nodes. Cerebral metastases of malignant thymoma is an extremely rare condition.
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  • 6
    ISSN: 1432-0533
    Keywords: Complement system ; Inflammation ; Blood-brain barrier ; Meningitis ; Cat model
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The effect of the complement-derived polypeptide C3adesArg as a mediator of inflammation in the central nervous system was examined. Twenty-five anesthetized cats received 4 mg of this polypeptide by intraventricular injection, 20 cats who served as controls received saline. Cerebrospinal fluid (CSF) was sampled 3 h after intraventricular injection and the brains were removed. For assessment of the permeability of the blood-brain barrier the CSF penetration of four antibiotics, which were given intravenously, was measured. Five control animals were employed for each antibiotic (tobramycin, ampicillin, imipenem, fosfomycin), whereas six C3adesArg-treated animals were used for each antibiotic and seven for tobramycin. Besides CSF levels of glucose, the prostanoids 6-keto-prostaglandin F1α, thromboxane B2 and prostaglandin E2 were measured. The morphological examinations in the CSF sediments and histological brain sections in the C3adesArg-treated animals disclosed a distinct inflammation with leptomeningeal and perivascular infiltration of polymorphonuclear granulocytes compared to normal findings in the controls. The CSF/serum ratios of all of the antibiotics were markedly elevated compared to controls, indicating a blood-brain barrier disruption. The levels of all prostanoids were significantly higher in the treatment group than in the control group, whereas the glucose levels were lower. These findings are in accordance with a granulocytic meningitis as seen in some infections at the acute stage. It is concluded that C3adesArg acts as a mediator of inflammation in the central nervous system.
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  • 7
    ISSN: 1432-0533
    Keywords: Key words Human ; Spinal cord trauma ; Axon ; regeneration ; Nerve growth factor receptor ; Schwann cell
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract To investigate the effects of Schwann cells and nerve growth factor receptor (NGFR) on the regeneration of axons, autopsy specimens of spinal cord from 21 patients with a survival time of 2 h to 54 years after spinal cord trauma were studied using immunohistochemistry and electron microscopy. Regenerating sprouts of axons could be observed as early as 4 days after trauma. At 4.5 months after trauma, many regenerating nests of axons appeared in the injured spinal cord. The regeneration nests contained directionally arranged axons and Schwann cells. Some axons were myelinated. In injured levels of the spinal cord, the Schwann cells exhibited an increased expression of NGFR within spinal roots. These results show that an active regeneration process occurs in traumatically injured human spinal cord. The NGFR expressed on Schwann cells could mediate NGF to support and induce the axon regeneration in the central nervous system.
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  • 8
    Electronic Resource
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    Acta neuropathologica 48 (1979), S. 211-214 
    ISSN: 1432-0533
    Keywords: Medullomyoblastoma ; Desmoplastic medulloblastoma ; Teratoid ; Ultrastructure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A case of cerebellar medullomyoblastoma in a young boy was investigated by electron microscopy. The neuroectodermal component shows the characteristics of a desmoplastic medulloblastoma. The mesodermal component consists of more or less differentiated cross-striated muscle cells. Undifferentiated muscle cells are very similar to proliferated endothelial cells of blood vessels within the muscular component, so that an origin of this component from pluripotential endothelial cells of the vessel wall is suggested. This tumor is considered a malignant teratoid because of the derivation from two blastodermic layers and because of the midline localization in children suggesting a malformative origin.
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  • 9
    ISSN: 1432-0533
    Keywords: Key words Parkinson’s disease ; Neural transplantation ; Allogeneic ; Major histocompatibility complex antigens ; Rat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Neural transplantation, as a therapeutic approach to Parkinson’s disease, still requires allogeneic graft material and raises questions of immunosuppression and graft rejection. The present study investigated the time course of major histocompatibility complex (MHC) expression and astrocytic response in allogeneic dopaminergic grafts, comparing two different grafting protocols. Adult 6-hydroxydopamine-lesioned Lewis 1.W rats received intrastriatal cell suspension grafts from the ventral mesencephalon of DA rat fetuses, either as single 1-μl macrograft via metal cannula or as four micrografts of 250 nl/deposit via a glass capillary. No immunosuppression was administered. Immunohistochemistry was performed at 1, 3, 6, and 12 weeks after grafting, using antibodies against donor- and host-specific MHC class I and II antigen, glial fibrillary acidic protein (GFAP) and tyrosine hydroxylase (TH). Most animals showed good allograft survival up to 12 weeks after transplantation with no signs of rejection. Reinnervation of the lesioned striatum by TH-positive neurites was observed from 3–6 weeks on. Expression of donor-specific MHC class I was comparably low in both allogeneic grafting groups, while host MHC class I and II reaction as well as astrocytic response tended to be higher in the macrografted animals. Donor MHC class II was not observed at any time point. It is concluded that intraparenchymal allografts of fetal mesencephalic cell suspensions can survive well in the rat Parkinson model without immunosuppression for at least 12 weeks, and that the expression of moderate amounts of donor-specific MHC class I antigen does not suffice to initiate a rejection process. In addition, the microtransplantation approach may reduce the level of trauma and subsequent MHC and GFAP expression and may, thereby, minimize the risk of graft rejection.
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  • 10
    ISSN: 1432-0533
    Keywords: Key words Abdominal brain ; Dysraphism ; Ectopic brain tissue ; Foix-Alajouanine syndrome ; Retroperitoneal tumor
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract An encapsulated mass of brain tissue was found in the retroperitoneum of a fetus of gestational week 15 and a boy of age 3 years. The masses possessed fibrous tissue that bound them to the spine and intraspinal connective tissue, respectively, but there was no evidence of direct continuity of the ectopic brain tissue with the normal central nervous system. There was no dysraphism. In our fetal case, possible Foix-Alajouanine anomaly was additionally found. The ectopic neural tissue in the retroperitoneal region may be termed “abdominal brain.” In the literature, an identical state has been described in the head (paracranial region) but there are no other records of the paraspinal region. Despite the different locations of the masses (head/paracranial or retroperitoneum/paraspinal), these ectopic brain masses should belong to the same disorder spectrum of the paraneuraxial neural ectopia, a new concept.
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