PubMed Health⌕ Search

Biomedical subjects

T Ikebe

Publications and source records attributed to T Ikebe.

At least 91 records · Page 5Linked to original sources
PubMed1987

Effect of guanosine triphosphate on the release and uptake of Ca2+ in saponin-permeabilized macrophages and the skeletal-muscle sarcoplasmic reticulum.

The effects of GTP, with or without polyethylene glycol (PEG), on the release and uptake of Ca2+ were examined by using saponin-treated macrophages and sarcoplasmic reticulum isolated from skeletal muscles. The application of GTP in concentrations in the range 0.1-10 microM induced a gradual, small but sustained release of Ca2+ from the saponin-treated macrophages. The addition of PEG to GTP markedly enhanced the GTP-mediated Ca2+ release. GTP at the same concentration ranges used for Ca2+ release decreased the amount of Ca2+ uptake, at a steady state, but stimulated the rate of Ca2+ accumulation in the presence of oxalate, the Ca2+-precipitating anion. The addition of PEG abolished the GTP-evoked stimulation of Ca2+ accumulation in the presence of oxalate. The stimulating effect on the rate of Ca2+ accumulation by GTP and its elimination by PEG were not due to changes in the permeability of oxalate by either GTP or PEG, or both. The Ca2+-releasing effect of GTP without PEG was enhanced by eliminating the uptake activity by decreasing the content of ATP. These results indicate that GTP has an inherent activity to release Ca2+ from non-mitochondrial intracellular stores of saponin-treated macrophages, and PEG enhances the GTP-mediated Ca2+ release, partly owing to its eliminating effect on GTP-stimulated Ca2+ uptake activity. These effects of GTP observed with saponin-permeabilized macrophages were not apparent in the isolated skeletal-muscle sarcoplasmic reticulum.

Animals↗
PubMed1986

Human recombinant interleukin 1-mediated suppression of glycosaminoglycan synthesis in cultured rat costal chondrocytes.

Effects of human recombinant interleukin 1 (IL-1) on the synthesis of glycosaminoglycan were examined with cultured rat costal chondrocytes. Incorporation of [35S]sulfate into glycosaminoglycan was strikingly diminished by the addition of IL-1 in a dose- and time- dependent manner. When the cells were cultured with 340 micrograms/ml of IL-1 for 72 hr, the synthesis of glycosaminoglycan was inhibited to 10% of the control. On the other hand, IL-1 had no effect on the morphology and proliferation of the chondrocytes. The suppression of glycosaminoglycan synthesis remained unchanged after the addition of indomethacin, indicating that the effect of IL-1 is independent of the enhanced synthesis of prostaglandins.

Animals↗
PubMedDate not supplied

Efficacy of major hepatic resection for large hepatocellular carcinoma.

BACKGROUND/AIMS: A large hepatocellular carcinoma (HCC) generally carries a poor prognosis despite curative hepatic resection. However, some cases have had good outcomes without recurrences. In this study, we investigated the factors which predicted a good prognosis. METHODOLOGY: Sixty-six patients with large HCC greater than 5 cm who underwent curative hepatic resections were divided into two groups. There were 55 patients who had recurrences within 5 years after surgery (group A) and 11 patients who did not have recurrences at the fifth year after surgery (group B). We compared the clinicopathological features between the two groups. RESULTS: No differences were seen in the pre-operative liver function tests and the incidence of histological cirrhosis. The incidence of positive rate of histological recurrence factors, such as intrahepatic metastasis and incomplete surgical margins, was significantly less in group B. Five (45%) and 10 (91%) of 11 patients in group B underwent pre-operative portal vein embolization and major hepatic resection, respectively, while 10 (18%) and 29 (53%) of 55 patients in group A underwent these procedures (p < 0.05). CONCLUSIONS: In order to increase tumor-free survival rates for patients with large HCC greater than 5 cm, major hepatic resection after portal vein embolization with complete surgical margins should be performed.

Aged↗
PubMedDate not supplied

Hyperplastic foci as a prognostic factor after resection of hepatocellular carcinoma.

BACKGROUND/AIMS: Since chronic liver disease is generally considered a pre-malignant condition, recurrence in the residual liver after hepatic resection for hepatocellular carcinoma may be related to the malignant potential of the underlying liver disease. METHODOLOGY: We studied non-cancerous regions of hepatocellular carcinomas that were 3 cm or smaller in diameter from 170 patients who underwent curative hepatic resection. The presence of clusters of hyperplastic small cells, which we called hyperplastic foci, was investigated microscopically. The nuclei of the cells in hyperplastic foci were normal, but the nuclear/cytoplasmic ratio was high, cellularity was increased compared with neighboring regions, and the hepatic trabeculae were somewhat thick. We also calculated the labeling index in hyperplastic foci areas by proliferating cell nuclear antigen and compared this to that of hepatocytes without cellular atypia. RESULTS: In 59 of 170 patients (35%), hyperplastic foci were found. The labeling index in hyperplastic foci was significantly higher than in control regions (p = 0.0016). As of December 1995, 113 patients (63%) were found to have a recurrence. When hyperplastic foci were found, the tumor-free survival rate was significantly lower (p = 0.0443). CONCLUSIONS: Hyperplastic foci represent an important predictor of recurrence after hepatic resection for a small hepatocellular carcinoma.

Adult↗
PubMedDate not supplied

Post-operative blood tests and multicentric recurrence of hepatocellular carcinoma.

Second hepatic resections (SHR) were performed in 2 patients with recurrent hepatocellular carcinoma (HCC) with hepatitis C virus (HCV) more than 10 years after initial curative resections. Appearance on imaging studies of the late recurrences thought to be multicentric primary tumors, was preceded by fluctuating laboratory abnormalities such as increased alanine aminotransferase activity (ALT), increased serum alpha-fetoprotein (AFP), and decreased platelet counts by as long as 2 years. Therefore, serial changes of blood tests after resection of HCC with HCV might be useful predictors of late multicentric recurrence.

Aged↗
PubMedDate not supplied

Patterns of and risk factors for recurrence after liver resection for well-differentiated hepatocellular carcinoma: a special reference to multicentric carcinogenesis after operation.

BACKGROUND/AIMS: We studied the patterns of, and risk factors for, recurrence after resection of well-differentiated hepatocellular carcinoma to make a strategy for such carcinoma. METHODOLOGY: The subjects were 36 patients who underwent liver resection for well-differentiated hepatocellular carcinoma. Multicentric carcinogenesis after the operation (multicentric recurrence) was diagnosed when a recurrent tumor included a component of well-differentiated hepatocellular carcinoma. Tumor-free survival rates of patients with various risk factors were calculated and differences between groups were evaluated. For multivariate analysis, Cox's proportional hazard model was used. RESULTS: All recurrent tumors after operation were of multicentric origin. Univariate analysis showed a history of blood transfusion, high alpha-fetoprotein concentration (> 20 ng/ml), and low platelet count (< 10(5)/mm3) to be significant factors. By multivariate analysis, a history of blood transfusion and a low platelet count were independent risk factors. Nonanatomic resection was not a risk factor. CONCLUSIONS: In patients with well-differentiated hepatocellular carcinoma, especially with risk factor(s) for multicentric recurrence, not only anatomic but also nonanatomic resection (partial resection) are indicated for a primary tumor, because almost all recurrent tumors are of multicentric origin. After resection of well-differentiated hepatocellular carcinoma, careful monitoring for multicentric recurrence is important in patients with risk factors.

Adult↗
PubMedDate not supplied

Ornithine decarboxylase activity in the non-cancerous hepatic tissue of patients with hepatocellular carcinoma.

BACKGROUND/AIMS: Hepatocellular carcinoma may develop in patients with chronic hepatitis and cirrhosis. Active hepatitis is an important etiologic factor in the development of hepatocellular carcinoma. We measured ornithine decarboxylase activity, an important enzyme during cell proliferation, in non-cancerous hepatic tissue in patients with hepatocellular carcinoma. METHODOLOGY: Thirty-four patients who underwent liver resection for hepatocellular carcinoma were the subjects of this study. Hepatitis B surface antigen was detected in 7 patients (HBV group) and hepatitis C virus antibody was detected in 27 patients (HCV group). Tissue ornithine decarboxylase activity was measured. Histologic severity in active hepatitis (activity score) and degree of fibrosis (staging score) were determined. RESULTS: Ornithine decarboxylase activity was significantly higher in the HCV group than in the HBV and control groups. In all patients, ornithine decarboxylase activity correlated directly with the histologic activity score and the histologic staging score. In the HCV group, ornithine decarboxylase activity correlated with the histologic activity score. CONCLUSIONS: Ornithine decarboxylase activity in non-cancerous hepatic tissue correlated with the severity of active hepatitis and degree of fibrosis. In patients with hepatitis C virus, active hepatitis with increased ornithine decarboxylase activity is an important factor in the development of hepatocellular carcinoma.

Adult↗