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Biomedical subjects

E Brauner

Publications and source records attributed to E Brauner.

At least 19 recordsLinked to original sources
PubMed1991

Neuronal and glial properties of a murine transgenic retinoblastoma model.

Antigenic properties of a murine transgenic model for hereditary retinoblastoma, induced by a chimeric gene coding for Simian virus 40 large T antigen, an oncogene that inactivates the retinoblastoma susceptibility gene product, were studied by immunohistochemistry. All transgenic mice develop bilateral intraocular retinal tumors in the inner nuclear layer with Homer Wright-like rosettes, and one quarter develop midbrain tumors resembling trilateral retinoblastoma. Cell lines TE-1 and TM-1 were established from intraocular and metastatic tumors, respectively. Intraocular tumors reacted with antibodies to neuron-specific enolase and synaptophysin, while vimentin, glial fibrillary acidic, and S-100 proteins were detected only in reactive glia derived from adjacent retina. The midbrain tumors showed weak reactivity to synaptophysin, and they blended with reactive astrocytes positive for glial markers. The tumors were negative for cytokeratins. Finally both derived cell lines expressed synaptophysin and individual neurofilament triplet proteins in immunofluorescence and Western blotting, supporting their essentially neuronal nature. The antigenic profile resembles human retinoblastoma, but differences in morphology and antigen distribution suggest a more close relationship to neurons of the inner nuclear layer than to photoreceptor cells.

Animals↗
PubMed1991

Primitive neuroectodermal tumor of the midbrain in a murine model of retinoblastoma.

The first heritable model of retinoblastoma was established by retina-specific expression of simian virus 40 T-antigen (SV40 T-ag) in transgenic mice. Bilateral, multifocal ocular tumors were observed in 100% of transgene-bearing mice. Central nervous system neoplasms occurred at a lower rate (27%) and represented the murine counterpart of human trilateral retinoblastoma. The authors characterized the transgenic brain tumors and found them to be primitive neuroectodermal tumors (PNET) of the midbrain. Murine brain tumors do not involve the pineal gland and most closely resemble undifferentiated suprasellar or parasellar tumors occasionally observed in human trilateral retinoblastoma. The murine malignancies arose from the subependymal cells of the cerebral aqueduct. Immunohistochemical and ultrastructural examination revealed that the transgenic brain tumors were undifferentiated and lacked all antigens associated with normal murine neuronal, glial, and ependymal cells.

Animals↗
PubMed1989

Comparative study of clindamycin, imipenem, oxacillin and vancomycin in the infected granuloma pouch model.

In a rat granuloma pouch model, Staphylococcus aureus infection was treated with clindamycin, oxacillin or vancomycin and Bacteroides fragilis infection with clindamycin or imipenem. The model simulates a subcutaneous abscess and has the advantage of permitting frequent sampling of exudate for bacterial counts and antibiotic levels in the same animal. In staphylococcal infection all drugs reduced the bacterial counts in the infected pouch by 1-1.7 log, with a significant effect lasting for 3 h after the last injection. A 1.06-1.4 log reduction lasted for 24 h with clindamycin and oxacillin, but there was only an 0.3 log reduction at 24 h with vancomycin. The ratio of the drug concentration in the infected pouch to the MIC was highest with clindamycin (2.3) compared to oxacillin (1.6) and vancomycin (0.8). With Bact. fragilis infection the bacterial counts dropped 1.5 log at 3 h after the last injection with clindamycin and imipenem. At 24 h the counts were reduced 1.0 log with clindamycin and 0.5 log with imipenem. The ratios of pouch fluid concentration to MIC was 7.6 and 4.08 for imipenem and clindamycin, respectively, at 3 h, and 1.0 and 2.3 for imipenem and clindamycin at 24 h.

Animals↗
PubMedDate not supplied

[Effectiveness of repeated antibiotic or chemotherapeutic treatments on Shigella carrier states].

A group of 39 former dysentery patients, who continued to excrete Shigella bacteria after a first cure of antibiotics when full clinical recovery was obtained, were treated differentially under bacteriological control. The carrier state was still extent in 7% of the cases after three antibiotic or chemotherapeutical cures. No direct relation was found between the sensitivity of Shigella to chemotherapeutics and the level of the carrier state. Although treated already in the acute stage with adequate antibiotics, resistance to a second therapeutical attempt was recorded in a proportion of 33%. It is considered useless to repeat the antibiotic or chemotherapeutical cures in the treatment of convalescent carriers because of the low efficiency and the biological and economical disadvantages.

Adolescent↗