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I Tabei

Publications and source records attributed to I Tabei.

9 recordsLinked to original sources
PubMed1997

Title not supplied by PubMed (PMID 11091618)

A comparative study of &sup201;Tl and &sup99m;Tc-methoxy-2 isobutyl isonitrile (&sup99m;Tc-MIBI)was performed in 39 breast tumors. &sup201;Tl scintigraphy was carried out in 24 breast tumors and &sup99m; Tc-MIBI scintigraphy in 15. The sensitivity of &sup201;Tl for malignant tumors was 100%(22/22), but specificity was 0%(0/2). On &sup99m;Tc-MIBI scintigraphy, the sensitivity for malignant tumors was 83.3%(10/12) and specificity was 100%(3/3). &sup99m;Tc-MIBI might be more useful for the diagnosis of breast tumors, because the tumor/background ratio of &sup99m;Tc-MIBI was significantly higher than that of &sup201;Tl. In addition, &sup201;Tl scintigraphy and &sup99m;Tc-MIBI scintigrtaphy showed the same degree of accuracy (93.3%) in detecting lymph node metastasis. Moreover, when either ultrasonography (US) with &sup201;Tl or &sup99m;Tc-MIBI scintigraphy was positive for lymph node metastasis, the accuracy of detection became 94.4% The combined use of ultrasonography and scintigraphy might improve the accuracy of diagnosis of lymph node metastasis.

Journal Article↗
PubMed1997

Treatment of surgically induced acute liver failure by transplantation of conditionally immortalized hepatocytes.

The shortage of human livers available for hepatocyte isolation limits its clinical application. The availability of cloned, conditionally immortalized hepatocytes that could be grown in culture but would lose their transformed phenotype and provide metabolic support upon transplantation would greatly facilitate the treatment of acute liver failure. Toward this goal, we transduced isolated Lewis rat hepatocytes using a replication-defective recombinant retrovirus capable of transferring a gene encoding a thermolabile mutant simian virus 40 T antigen (SV40ts). The cloned, immortalized hepatocytes proliferate at 33 degrees C. At the nonpermissive temperatures (37-39 degrees C), they stop growing and exhibit characteristics of differentiated hepatocytes. These cells did not produce tumors when transplanted in mice with severe combined immunodeficiency disease or in syngeneic rats. To induce acute liver failure, Lewis rats were subjected to 90% hepatectomy (Hpx) and given 5% oral dextrose. All rats that did not undergo hepatocyte transplantation died within 96 hr. Fifty percent of rats that received intrasplenic injection of 10 x 10(6) primary Lewis rat hepatocytes (G2, n=6) or 10 x 10(6) SV40ts-conditionally immortalized (SV40ts-ci) hepatocytes (G3, n=8) 1 day before 90% hepatectomy survived, whereas 80% of rats that received an intraperitoneal injection of 200 x 10(6) primary Lewis rat hepatocytes (G4, n=10) or 200 x 10(6) SV40ts-ci hepatocytes (G5, n=10) on the day of hepatectomy survived. Survival after intraperitoneal injection of a cellular homogenate of 200 x 10(6) primary Lewis rat (G7, n=9) or SV40ts-ci hepatocytes (G8, n=10) on the day of Hpx was 33% and 40%, respectively, whereas survival after intraperitoneal injection of 200 x 10(6) Lewis rat bone marrow cells (G6, n=7) was 29%. Thus, transplanted, conditionally immortalized hepatocytes can be as effective as primary hepatocytes in supporting life during acute liver insufficiency. This work represents the first step in developing an hepatocyte cell line that would partially alleviate the organ-donor shortage and could be of potential clinical value.

Animals↗
PubMedDate not supplied

Characteristics of hepatocytes derived from early ES cells and treatment of surgically induced liver failure rats by transplantation.

BACKGROUND: Although liver transplantation has become a standard therapy for diseases such as fulminant hepatitis and cirrhosis, the lack of donor organs remains a major problem. One solution is the development of transplantable hepatocytes. The metabolic characteristics as well as function and adaptation of hepatocytes (R-EES-hep cell) derived from rat early embryonic stem cells were examined after transplantation into rats with surgically induced liver failure. METHODS: Rat hepatocyte cell lines were established from early embryonic stem cells cultured in the presence of embryotrophic factors by colony cloning methods. The cell lines were established from two cell embryos taken from spontaneous dwarf rats using the novel method of Ishiwata et al. Morphologic differentiation as well as albumin and bilirubin production were observed by immunostaining. R-EES-hep cells were transplanted into the spleens of 90% hepatectomized, surgically induced liver failure rats to analyze survival rates. RESULTS: When cultured in type I collagen gel the cells formed cordlike structures resembling the liver. Both albumin and bilirubin production were observed when transplanted; the spleen was converted into a liver-like structure with prolonged survival of the 90% hepatectomized rats for up to 3 months up to the time of killing. CONCLUSIONS: R-EES-hep cells showed many of the distinctive metabolic characteristics of the liver. These cells may be efficient for further research and application for hepatic cell transplantation to treat liver insufficiency patients and as biologic artificial organs.

Animals↗