Biomedical subjects

T Kaiho

Publications and source records attributed to T Kaiho.

46 records · Page 3Linked to original sources

PubMed1983

Establishment and properties of a human choriocarcinoma cell line of ovarian origin.

A human nongestational choriocarcinoma cell line of ovarian origin (IMa) was established in vitro. This cell line had been subcultured serially more than 22 times over 18 months. Small polygonal cells with a prominent nucleus were dominant and a sparsity of cytoplasmic organelles was an ultrastructural characteristic of the IMa cells. The production and secretion of human chorionic gonadotropin and its subunits were identified by radioimmunoassay. The IMa cells were transplantable in the hamster cheek pouch and the histological diagnosis was choriocarcinoma. A newly established ovarian choriocarcinoma cell line can be considered useful for clarifying the biological differences between nongestational and gestational choriocarcinoma cells.

Animals↗

PubMed1983

A newly established human gestational choriocarcinoma cell line and its characterization.

The cell biological characteristics of a newly established human gestational choriocarcinoma cell line, HM, were examined and compared with four other gestational and two nongestational choriocarcinoma cell lines. Striking heterogeneity in the production and secretion of hCG and its subunits was observed among the cell lines. The HM cell line consisted mainly of cytotrophoblast-like cells, and the hCG and its subunit values in both the cells and culture fluid were extremely low. The syncytiotrophoblast-like multinucleated giant cells which were occasionally seen in other cell lines were scarce in the HM cell line in vitro. On the other hand, deviation of the LDH isozyme pattern to the heart-type (LDH1) was characteristic of the HM cells in contrast to the other cell lines in which LDH3 was dominant. The HM cell line represents useful material for investigating the cell biological heterogeneity of human choriocarcinomas.

Adult↗

PubMed1983

Characterization of human choriocarcinoma cell lines secreting high and low amounts of chorionic gonadotropin.

The secretory potential of human chorionic gonadotropin (hCG) in eight strains of human choriocarcinoma cell lines was examined in vitro and the correlation between the secretory potential and certain cell biological characteristics was studied. Multinucleated giant cells (syncytiotrophoblast-like cells) were occasionally observed only in high hCG-secreting cell lines in accordance with inhibition of growth. Appearance of abundant dilated rough endoplasmic reticulum and aggregated glycogen particles in the cytoplasm seemed to represent ultrastructural characteristics of high hCG-secreting cell lines. A shift of nuclear DNA to hyperploidy, its wide distribution, and S phase accumulation of cells by flow cytometry were also characteristic of them. However, no correlation was noted between the hCG secretory potential and population doubling time of the cell lines in vitro.

Cell Line↗

PubMed1983

[Characterization of two choliocarcinoma cell lines and their sensitivity to MTX].

Both the sensitivity to MTX and hCG secretion were compared in two choriocarcinoma cell lines (BeWo and HCCM-5) and study on mechanisms about MTX-resistance was described. The uptake of nucleotides and protein precursors was decreased in dose-dependent manner in both cell lines when exposed to MTX, but HCCM-5 cells showed more sensitivity to MTX. In HCCM-5 cells, both hCG and hCG-beta levels in the medium were decreased with exposure to 10(-9)M MTX, but they tended to increase when exposed to higher concentration of MTX in contrast to the inhibition of 3H-thymidine uptake. However, in BeWo cells, an inverse relationship between the incorporation of 3H-thymidine and secretion of hCG was not clearly observed. The content of dihydrofolate reductase (DHFR) in HCCM-5 cells was about one-half of that in BeWo cells. Although the peak of 3H-MTX incorporation was observed at 120 minutes in both cell lines, HCCM-5 cells incorporated about 4 times higher 3H-MTX than BeWo cells. The difference of sensitivity to MTX between those two cell lines seems to be concerned with both the decrease of MTX transport and increase of intracellular DHFR levels.

Animals↗

PubMed1983

[MTX sensitivity and the mechanism of resistance of various choriocarcinoma cells in culture].

The sensitivity to methotrexate (MTX) and mechanisms of the drug resistance of seven kinds of human choriocarcinoma cell lines were studied in vitro. The results were as follows. Each cell line of HCCM-5 , BeWo, IMa, and NUC-1 secreted more than 200ng/10(6) cells/48 hours of human chorionic gonadotropin (hCG), whereas GCH-1, ENAMI-1, and SCH secreted less than 20ng/10(6) cells/48 hours. HCCM-5 cell line was the most sensitive to MTX judging from the inhibition of both 3H-thymidine uptake and cell growth in vitro. Each cell line of BeWo, IMa, and NUC-1 revealed sensitivity to 2 X 10(-8)M MTX, but such cell lines as GCH-1, ENAMI-1, and SCH showed resistance to MTX. The cell lines which revealed sensitivity to MTX incorporated more 3H-MTX and showed less intracellular dihydrofolate reductase activity than resistant cell lines.

Cell Line↗

PubMed1982

An extracellular poly(3-hydroxybutyrate) depolymerase from Alcaligenes faecalis.

A strain of Alcaligenes faecalis T1, which was isolated from activated sludge, excreted an extracellular poly(3-hydroxybutyrate) depolymerase as it grew in a medium containing poly(3-hydroxybutyrate) as the sole carbon source. The molecular weight of the enzyme, purified from the culture medium to electrophoretic homogeneity, was 48 000 as determined by Sephadex G-100 filtration, and 50 000 by polyacrylamide gel electrophoresis in the presence of sodium dodecylsulfate. The pH optimum for the enzyme reaction was 7.5. The purified enzyme depolymerized poly(3-hydroxybutyrate) purified from Zoogloea ramigera 1-16-M, but did not attack the bacterial native poly(3-hydroxybutyrate)-containing granules. Km values were 13.3 micrograms/ml (= 0.78 microM, based on an estimated average molecular weight of 17 000) for poly(3-hydroxybutyrate) and 5.4 mM for the trimeric ester of D(--)-3-hydroxybutyric acid. Analysis of hydrolytic products of poly(3-hydroxybutyrate), several oligomeric esters of D(--)-3-hydroxybutyric acid, and the methyl ester of the trimeric ester indicated that the enzyme hydrolyzed these substrates from the free hydroxyl terminus, releasing D(--)-3-hydroxybutyrate dimer units one at a time.

Alcaligenes↗

PubMed1982

[Antitumor effect of interferon against human choriocarcinoma cell lines].

In this report, we describe the inhibitory effect of two kinds of human interferons, IFN-alpha and IFN-beta, on the growth of human choriocarcinoma cell lines in vitro and in vivo on comparing the other various cell lines derived from gynecologic malignancies. As compared to human endometrial (HEC-1B) or ovarian (HOC-21) adenocarcinoma cells which were highly resistant to the inhibitory effect of IFN-beta on the DNA synthesis at any doses up to 10,000U/ml, two human choriocarcinoma cell lines, BeWo and HCCM-5, and yolk sac tumor cell line YS-K were relatively sensitive. However, the inhibition was not dose-dependent. The growth of BeWo and HCCM-5 cells were also inhibited by either IFN-alpha or IFN-beta at concentration of 1,000U/ml and the inhibition became conspicuous when the treatment was prolonged to 4 days or more. When the hamsters transplanted with BeWo or HCCM-5 cells were treated with 10,000U IFN-beta on every day from the first till the 7th day after inoculation of cells, the tumor weights decreased to about one-half of those of non-treated controls. In contrast, the tumor weights were almost the same as non-treated controls when the animals were given with IFN-beta from the 7th day till the 13th day.

Animals↗

PubMedDate not supplied

A case of classical carcinoid tumor of the gallbladder: review of the Japanese published works.

A 58 year-old man was admitted to Kimitsu Chuo Hospital complaining of epigastralgia. Abdominal ultrasound and computed tomography revealed a polypoid lesion at the neck of the gallbladder. Given the pre-operative diagnosis of gallbladder carcinoma, we resected the gallbladder along with the extrahepatic bile duct. There was a papillary tumor (25 x 16 mm) at the neck of the gallbladder. Histopathological examinations showed a subserosal nodular proliferation of uniform small tumor cells. Grimelius staining was slightly positive and Fontana-Masson staining was negative. Most of the tumor cells stained positively for chromogranin A and neuron-specific enolase (NSE), and some of the tumor cells were positive for pancreatic polypeptide. The presence of neurosecretory intracytoplasmic granules was proven ultrastructurally. It was diagnosed as a classical carcinoid tumor of the gallbladder. We reviewed the Japanese reported cases and discussed the difference in clinicopathological findings between classical and atypical carcinoid tumors of the gallbladder. Classical carcinoids of the gallbladder have neither a metastatic nor invasive character, and an extremely favorable prognosis compared with atypical carcinoids. The difference in character between classical and atypical carcinoids of the gallbladder is thought to be derived from their histogenetic origin.

Carcinoid Tumor↗

PubMedDate not supplied

Treatment of unresectable hepatic hilar malignancies with self-expanding metallic stents.

BACKGROUND/AIMS: This study assesses the treatment of biliary obstruction in patients with hilar malignancies by metallic stents. METHODOLOGY: Twenty-one consecutive patients with unresectable malignant biliary obstruction at the hepatic hilum (Bismuth type II, III and IV) were treated with percutaneous transhepatic placement of self-expandable metallic endoprostheses. The endoprostheses were successfully inserted in all patients. In 12 patients all segments of the liver were drained and in 9 patients partial segments of the liver were drained. RESULTS: Seventeen patients (81%) showed relief from jaundice and could be freed of external drainage tubes. Ten patients (48%) showed no recurrent symptoms due to stent obstruction until death. Overall survival was 4.86+/-4.15 (mean+/-SD) months, stent patency was 3.76+/-3.64 months and comfort index representing a ratio of well-being was 70.5+/-38.3%. There was no significant difference in survival rate, stent patency or comfort index between the groups with complete and those with partial drainage. CONCLUSIONS: Even in patients with complicated hepatic hilar biliary occlusions, internal drainage using metallic stents can relieve jaundice and leave patients free of external tubes with a comfortable quality of life.

Aged↗

PubMedDate not supplied

A successful treatment for hepatocellular carcinoma with atrial tumor thrombus.

A 66-year-old man with an advanced hepatocellular carcinoma and tumor thrombus extending into the right atrium was treated by transcatheter arterial infusion of lipiodol and aclarubicin. This brought about a remarkable reduction of the tumor and the disappearance of the right atrial tumor thrombus. The tumor was then radically resected by hepatic posterior segmentectomy with combined resection of the right hepatic vein, where the tumor thrombus remained. He is doing well without any signs of recurrence 22 months after the operation.

Aclarubicin↗