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K Nabeshima

Publications and source records attributed to K Nabeshima.

116 records · Page 7Linked to original sources

Sequential degradation of interstitial collagen by metalloproteinases extracted from tumors of murine ascites hepatomas.

Gelatinolytic and collagenolytic proteinases were separately isolated by different extraction methods from the mouse ascites hepatoma MH134, and from rat ascites hepatoma AH109A. The activities of two proteinases in each extract showed no significant differences, but after trypsin activation the activities of proteinases from the highly metastatic MH134 were significantly increased compared to the enzyme activities in AH109A, which has low metastatic potential. The total activities of collagenase and gelatinase were increased 7.2- and 5.1-fold; their specific activities were increased 5.2- and 4.8-fold, respectively. Gelatinase and collagenase from MH134 were characterized on gelatin zymography. The gelatinase had a molecular weight of 99 and activation by 4-aminophenylmercuric acetate (APMA) or trypsin resulted in its conversion to 79 or 79-95 kD, respectively. The collagenase revealed a major gelatinolytic band at 89 kD, which was converted to 85 and 70 kD by APMA-activation, and a minor gelatinolytic band at 60 kD. These proteinases could degrade native type I collagen to small fragments in a cooperative manner. Trypsin inhibitor, which affects the trypsin activation of latent gelatinase, was extracted together with gelatinase. The inhibitory activity of the enzyme from AH109A showed a 4.1-fold higher specific activity and 3.7-fold greater total activity than that from MH134. The proteinase(s) capable of activating the gelatinase was also extracted from MH134.

Animals↗

Intraoperative squash and touch cytology of chondroid chordoma of the skull base. Report of a case with immunocytochemical and immunohistochemical studies.

BACKGROUND: Chondroid chordoma is a rare variant of chordoma and is usually located in the sphenooccipital region. This tumor shows clinical and histologic features common to both conventional chordoma and low grade chondrosarcoma and has a better prognosis than either of those lesions. To our knowledge, there has been no English language report describing its cytologic features. CASE: The cytologic features of skull base chondroid chordoma observed in intraoperative crush and touch preparations from a 33-year-old female are reported. Touch cytology revealed round or stellate cells distributed in a mucoid background without a typical epithelial cordlike arrangement. The cells had variably vacuolated cytoplasm and round or oval nuclei and showed slight cellular pleomorphism. May-Giemsa staining was superior to Papanicolaou staining in demonstrating the mucoid matrix and vacuolated cytoplasm of the tumor cells. Additionally, crush preparations were effective in demonstrating well-differentiated chondroid elements. Immunocytochemistry with positivity for S-100 protein and cytokeratins was an essential adjunct in the cytologic diagnosis of chordoma and helped in distinguishing it from other chondrogenic tumors. CONCLUSION: It is possible and advantageous to diagnose chondroid chordoma with a combination of cytologic and immunocytochemical studies of intraoperative crush and touch preparations in conjunction with clinical and radiographic information.

Adult↗