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L D Leder

Publications and source records attributed to L D Leder.

137 records · Page 8Linked to original sources
PubMedDate not supplied

Variability of differentiation patterns in xenotransplanted spindle cell sarcomas: a histomorphological, immunohistochemical, and ultrastructural study.

Three leiomyosarcomas, 3 nerve sheath sarcomas, 1 rhabdomyosarcoma, and 1 sarcoma not otherwise classifiable with 17 of their xenografts, grown on nude mice, were analyzed to assess the degree of concordance between histomorphology, immunohistochemistry, and ultrastructure in spindle cell sarcoma xenograft differentiation. Histomorphology was inconclusive or misleading in 4/8 sarcoma strains and immunohistochemistry in 4/8 originals and in 10/17 xenografts, although specific patterns had been identified ultrastructurally. Electron microscopy was superior to immunohistochemistry and histomorphology in spindle cell sarcoma differential diagnosis. A further purpose of this study was to clarify whether spindle cell sarcoma xenografts retain the morphological characteristics of their primaries. Histomorphological features of the primaries were preserved over all passages, whereas the immunohistochemical marker profiles as well as the ultrastructural phenotypes changed in 14/17 xenografts and in 8/17 xenografts, respectively. Moreover, unusual bidirectional or tridirectional patterns of differentiation were identified ultrastructurally with leiomyomatous as well as Schwann cells occurring side by side and with MFH-like areas in 5/17 xenotransplants. These findings suggest genetic instability of tumor cells and may be important in the consideration of mesenchymal differentiation pathways.

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PubMedDate not supplied

[Inverted papilloma: implications for the oral and maxillofacial surgeon].

7 patients with inverted papillomas of the maxillofacial area were subjected to a post-treatment evaluation. Inverted papillomas were found in maxillary and frontal sinuses, ethmoid cells, nasal septa and as isolated lesions in the mucosa of the mandibular alveolar process. Apart from an inverted papilloma, one patient also had a mucoepidermoid carcinoma. The tendency to recur correlated well with the surgical approach. Radical removal of the mucosa must be called for as primary therapy in the paranasal sinus area. In order to safely exclude a concurrent carcinoma, the entire resected material must be examined histologically.

Adult↗
PubMedDate not supplied

[Partially common antigenicity of macrophages, epitheloid cells and foreign body giant cells. Experimental studies on rats].

QUESTION: By means of antimacrophage sera it is possible to demonstrate partially common antigenicity of monocytes with peritoneal macrophages, reticulum cells capable of phagocytosis, mast cells and Kupper's cells. The authors continued these studies important for the explantation of cytogenetical interrelations using a special method on epitheloid and giant cells of rats. The experiments aimed for the detection of possible partially common antigenicity with the above mentioned monocytes/macrophages system.

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