Actin sheath

Berven et al. described the toxic effects induced by OA after intravenous injection in rats (100-200 g). The toxin (50-500 4g/kg) had little effect on intestinal function, but caused liver damages. At doses of 0.2 pg/kg or more, rats became inactive, cyanotic, and died within few hours. Autopsy and histological examination revealed a pronounced congestion of blood in the liver and a dissolution of hepatic bile canalicular actin sheaths, but neither the microtubular nor the keratin network of hepatocytes was affected by the toxin. Similarly, administration of OA did not induce apoptotic DNA fragmentation in hepatocytes. 

Reuzeau C, Doolittle KW, McNally JG, Pickard BG. Covisualisation in living onion cells of putative integrin, putative spectrin, actin, putative intermediate filaments, and other proteins at the cell membrane and in an endomembrane sheath. Protoplasma 1997 199 173-197. 

KER, keratin, detected by a mixture of GAMS.2, MAK-6, and AEl /AE3 EMA, epithelial membrane antigen VIM, vimentin DES, desmin MSA, muscle-specific actin SMA, smooth muscle (alpha isoform) actin GALD, h-caldesmon S-IOOP, S-100 protein OCN, osteocalcin LM, laminin UL, Ulex europaeus I lectin binding FS, fibrosarcoma SGRMS, spindle cell rhabdomyosarcoma LMS, leiomyosarcoma MPNST, malignant peripheral nerve sheath tumor MSS, monophasic spindle cell synovial sarcoma SCAS, spindle cell angiosarcoma KS, Kaposi s sarcoma FOS, fibroblastic osteosarcoma. 

Fibroma of tendon sheath and collagenous fibroma (desmoplastic fibroblastoma) are usually sufficiently distinct clinically and histologically to separate them from fibromatosis. They often react either diffusely or focally for muscle-specific actin and smooth muscle actin and may even show faint S-100 positivity.Desmin, however, is not found. In addition to sharing an immunophenotypic profile, fibroma of tendon sheath and collagenous fibroma have been observed to harbor the same abnormality of chromosome... 

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