Bibliothek

feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
Filter
  • Cortical tuber  (2)
  • Argon laser-induced thermal injury  (1)
  • 1
    ISSN: 1432-0533
    Schlagwort(e): Key words Tuberous sclerosis ; Cortical tuber ; Subependymal giant cell astrocytoma ; Immunoelectron ; microscopy ; Crystalloid
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract The cellular nature of the giant eosinophilic cells of tuber and of the cells comprising subependymal giant cell astrocytoma (SEGA) in tuberous sclerosis (TS) remains unclear. To assess the characteristics of these lesions, 13 tubers and 6 SEGA were immunohistochemically studied with glial and neuron-associated antigens. In addition to conventional ultrastructure, 6 tubers and 8 SEGA were subjected to immunoelectron microscopic study for glial fibrillary acidic protein (GFAP) and somatostatin. Eosinophilic giant cells of tubers were positive for vimentin (100%), GFAP (77%) and S-100 protein (92%); such cells were also found to a various extent to be reactive for neuron-associated antigens, including neurofilament (NF) proteins (38%) or class III β-tubulin (77%). SEGA also showed variable immunoreactivity for GFAP (50%) or for S-100 protein (100%); NF epitopes, class III b-tubulin, and calbindin 28-kD were expressed in 2 (33%), 5 (83%) and 4 (67%) cases, respectively. Cytoplasmic staining for somatostatin (50%), met-enkephalin (50%), 5-hydroxytryptamine (33%), β-endorphin (33%) and neuropeptide Y (17%) was noted in SEGA, but not in tubers. Ultrastructurally, the giant cells of tubers and the cells of SEGA contained numerous intermediate filaments, frequent lysosomes and occasional rectangular or rhomboid membrane-bound crystalloids exhibiting lamellar periodicity and structural transition to lysosomes. Some SEGA cells showed features suggestive of neuronal differentiation, including stacks of rough endoplasmic reticulum, occasional microtubules and a few dense-core granules. Furthermore, in one case of tuber, a process of a single large cell was seen to be engaged in synapse formation. Intermediate filaments within a few cells of both lesions were decorated by gold particle-labeled GFAP antiserum. Within the tumor cells of SEGA, irregular, non-membrane-bound, electron-lucent areas often contained somatostatin-immunoreactive particles, whereas the latter could not be detected in tuber. The present study provides further evidence of divergent glioneuronal differentiation, both in the giant cells of tubers and the cells of SEGA. The findings of similar cells at different sites, including the subependymal zone, white matter ("heterotopias"), and cortex indirectly supports the idea that these lesions of TS result from a migration abnormality.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 2
    ISSN: 1432-0533
    Schlagwort(e): Tuberous sclerosis ; Cortical tuber ; Subependymal giant cell astrocytoma ; Immunoelectron microscopy ; Crystalloid
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract The cellular nature of the giant eosinophilic cells of tuber and of the cells comprising subependymal giant cell astrocytoma (SEGA) in tuberous sclerosis (TS) remains unclear. To assess the characteristics of these lesions, 13 tubers and 6 SEGA were immunohistochemically studied with glial and neuron-associated antigens. In addition to conventional ultrastructure, 6 tubers and 8 SEGA were fibrillary acidic protein (GFAP) and somatostatin. Eosinophilic giant cells of tubers were positive for vimentin (100%), GFAP (77%) and S-100 protein (92%); such cells were also found to a various extent to be reactive for neuron-associated antigens, including neurofilament (NF) proteins (38%) or class III β-tubulin (77%). SEGA also showed variable immunoreactivity for GFAP (50%) or for S-100 protein (100%); NF epitopes, class III β-tubulin, and calbindin 28-kD were expressed in 2 (33%), 5 (83%) and 4 (67%) cases, respectively. Cytoplasmic staining for somatostatin (50%), met-enkephalin (50%), 6-hydroxytryptamine (33%), β-endorphin (33%) and neuropeptide Y (17%) was noted in SEGA, but not in tubers. Ultrastructurally, the giant cells of tubers and the cells of SEGA contained numerous intermediate filaments, frequent lysosomes and occasional rectangular or rhomboid membrane-bound crystalloids exhibiting lamellar periodicity and structural transition to lysosomes. Some SEGA cells showed features suggestive of neuronal differentiation, including stacks of rough endoplasmic reticulum, occasional microtubules and a few dense-core granules. Furthermore, in one case of tuber, a process of a single large cell was seen to be engaged in synapse formation. Intermediate filaments within a few cells of both lesions were decorated by gold particle-labeled GFAP antiserum. Within the tumor cells of SEGA, irregular, non-membrane-bound, electron-lucent areas often contained somatostatin-immunoreactive particles, whereas the latter could not be detected in tuber. The present study provides further evidence of divergent glioneuronal differentiation, both in the giant cells of tubers and the cells of SEGA. The findings of similar cells at different sites, including the subependymal zone, white matter (“heterotopias”), and cortex indirectly supports the idea that these lesions of TS result from a migration abnormality.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 3
    Digitale Medien
    Digitale Medien
    Springer
    European archives of oto-rhino-laryngology and head & neck 253 (1996), S. 193-200 
    ISSN: 1434-4726
    Schlagwort(e): Fiberoptic argon laser stapedotomy ; Skeeter microdrill stapedotomy ; Inner ear ; Temperature measurements ; Argon laser-induced thermal injury
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Since 1992 a small air-cooled opthalmological argon laser (Augus system, 3 W max.) equipped with a fiberoptic microhandpiece has been used for stapedotomy at the Inselspital, Berne. The microhandpiece has been developed especially for otological purposes in our electronic laboratory. In order to measure the effect of argon laser pulses applied through the handpiece to the ear, we performed temperature measurements in a saline-filled inner ear model by using ultrathin (2 μm thick), ultrafast (4 ns) thermosensitive rhodamine-coated polyurethane films. Multiple laser pulses of 1–2.5 W and 0.1 s duration — as used in clinical applications — produced a temperature elevation of about 1 ° C in the liquid of the inner ear model. The local laser effect was then examined histologically on the isolated stapes. The thermal damage zone around the stapedotomy perforation was limited to about 100 μm. In a clinical study we compared the results of argon laser stapedotomy (n = 54) with those of a skeeter microdrill stapedotomy (n = 29). Substantial hearing gains were found in all cases in both groups. In the laser stapedotomy group the mean residual air-bone gap (0.5–2 kHz) was 10 dB or less in all cases but one. Inner ear function remained unchanged except for a 40-dB loss at 4000 Hz in one case. Transient vertigo with nystagmus occurred in one case. Facial nerve dysfunction did not occur in any patient. The most important advantage of the laser found was the absence of mechanical trauma to the stapes. Stapes luxation and a floating footplate were avoided. In contrast, thick footplates were more easily perforated with the skeeter. Use of an argon laser equipped with a fiberoptic microhandpiece and a skeeter microdrill as needed seems particularly advantageous for stapedotomy.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...