Search PubMed⌕ Search

Biomedical subjects

T Motoyama

Publications and source records attributed to T Motoyama.

At least 109 records · Page 6Linked to original sources
PubMed1994

Different characteristics of hepatoid and non-hepatoid alpha-fetoprotein-producing gastric carcinomas: an experimental study using xenografted tumors.

The characteristics, including metastatic potential, of 5 xenografts of alpha-fetoprotein (AFP)-producing gastric carcinomas in nude mice, designated TSG1, TSG3, TSG11, TSG17 and TSG20, were examined. Of these xenografts, TSG1, TSG11 and TSG20 were regarded as hepatoid adenocarcinomas based on their morphological resemblance to hepatocellular carcinoma, frequent immunoreactivity for liver-cell markers, and excessive production of AFP with a high concanavalin A (Con-A)-binding property of hepatic type. On the other hand, TSG3 and TSG17 tumors showed the features of poorly differentiated medullary adenocarcinoma with scattered AFP-positive cells consistent with low AFP levels in mouse sera, and negative immunoreactivity for other liver-cell markers. Ultrastructurally, these tumors were composed of undifferentiated cells with a little adenocarcinomatous differentiation. Moreover, the AFP produced by TSG3 and TSG17 tumors had an extremely high Con-A nonbound fraction (80% to 90%), which was different from that of the hepatic or yolk-sac types. Therefore, both TSG3 and TSG17 tumors were regarded as non-hepatoid, poorly differentiated adenocarcinomas which could be differentiated from any types of AFP-producing gastric carcinoma. Furthermore, cells from hepatoid adenocarcinoma strains (TSG1, TSG11 and TSG20) injected into the spleens of nude mice produced liver metastases in all the mice examined, whereas cells from non-hepatoid carcinoma strains (TSG3 and TSG17) produced few or no liver metastases. Our data show that some non-hepatoid AFP-producing gastric carcinomas have lower liver-metastasizing potential than hepatoid AFP-producing gastric carcinomas.

Adenocarcinoma↗
PubMed1994

Functional and morphological effects of tumour necrosis factor alpha in an interleukin 6-producing pulmonary large cell carcinoma with sarcomatoid features.

We established a clonal cell line, HAT.MC8, derived from a human pulmonary large cell carcinoma with sarcomatoid features. This cell line was successfully maintained in a protein-free medium and exhibited sarcomatoid fibroblastic features in vitro. The cells constitutively produced a large amount of interleukin 6 (IL-6) in vitro. Tumour necrosis factor alpha (TNF-alpha) not only stimulated HAT.MC8 cells to produce IL-6, but also induced a morphological change from sarcomatoid fibroblastic to epithelial features. Although this change was related to actin and zonula adherens, there was no evidence that E-cadherin participated in the change. Interleukin 1 beta (IL-1 beta) had a stimulatory effect on IL-6 production by HAT.MC8 cells, but no influence on the morphology of the cells.

Carcinoma, Non-Small-Cell Lung↗
PubMed1994

Ciliated carcinoma of the endometrium associated with mucinous and neuroendocrine differentiation: a case report with immunohistochemical and ultrastructural study.

A case of endometrial ciliated carcinoma mixed with foci of mucinous adenocarcinoma and argyrophil cells is described. The patient suffered from diabetes mellitus, hypertension and obesity, but had no history of estrogen use. Although the tumor presented well differentiated histologic features, it showed complete diffuse, endophytic extension. Approximately half of the cilia had abnormal inner structures, with 8 + 2 microtubular pattern. Some ciliated cells contained intracytoplasmic mucin, while others contained neurosecretory granules. These findings suggest that malignant ciliated cells have the capacity of further transformation into mucinous or endocrine cells.

Adenocarcinoma, Mucinous↗
PubMed1994

Neoplastic and non-neoplastic intermediate trophoblasts: an immunohistochemical and ultrastructural study.

Five cases of non-molar trophoblastic disease including one placental site trophoblastic tumor (PSTT), two exaggerated placental sites and two choriocarcinomas were compared with each other and with normal chorionic villi and placental site. This involved light microscopic, immunohistochemical and ultrastructural studies. Comparison of PSTT with choriocarcinoma suggested that the former represented a neoplastic transformation of placental site intermediate trophoblast. The PSTT showed a characteristic immunohistochemical distribution of human placental lactogen and human chorionic gonadotropin, resembling that of the placental site intermediate trophoblast. Placental site trophoblastic tumor cells were also characterized ultrastructurally by prominent perinuclear filaments, abundant rough endoplasmic reticulum, or both. Infiltrating intermediate trophoblasts in exaggerated placental sites were similar to PSTT cells rather than normal placental site intermediate trophoblasts. However cells with vacuolated cytoplasm or spindle-shaped intermediate trophoblastic cells were observed more frequently in the PSTT than the exaggerated placental sites. The intermediate trophoblastic cells in the choriocarcinomas showed a morphologically transitional form from cytotrophoblastic cell to syncytiotrophoblastic cell, but did not share unique ultrastructural similarities with placental site intermediate trophoblasts.

Adult↗
PubMed1994

Coexistence of choriocarcinoma and hepatoid adenocarcinoma in the stomach.

The case is presented of a 46 year old woman who had a gastric tumor with components of choriocarcinoma, hepatoid adenocarcinoma and common types of adenocarcinoma. Although two histologic types of tumor producing carcinoplacental or carcinofetal proteins were contained within the tumor, immunohistochemical analyses, especially of placental alkaline phosphatase, clearly showed that each component was present separately within the same tumor. It was only hepatoid adenocarcinoma cells that permeated the lymph and blood vessels. After the recurrence, the serum level of alpha-fetoprotein (AFP) markedly elevated, but that of human chorionic gonadotropic beta-subunit (hCG-beta) was always within normal range. These findings indicate that in the present case the hepatoid adenocarcinoma component was more aggressive in growth than the choriocarcinoma component.

Adenocarcinoma↗
PubMed1994

Isolation and characterization of two chitin synthase genes of Rhizopus oligosporus.

Two chitin synthase genes (chs1 and chs2) were isolated from Rhizopus oligosporus by plaque hybridization probed with the chitin synthase 2 gene of Saccharomyces cerevisiae. From their deduced amino acid sequences, they were both class II chitin synthases according to the classification proposed by Bowen et al. The expression of these genes was controlled differently in each stage of differentiation. It was suggested that the gene products of chs1 and chs2 function mainly in the hyphae growing stage but not in the late stage of spore formation. When each of these genes was expressed in S. cerevisiae, elevation of chitin synthase activity was observed in both cases.

Amino Acid Sequence↗
PubMed1994

Isolation of a chitin synthase gene (chsC) of Aspergillus nidulans.

We isolated a class I chitin synthase gene (chsC) from Aspergillus nidulans. Expression of this gene was confirmed by Northern analysis and by sequencing of the PCR-amplified DNA fragments from cDNA. chsC disruptants showed no difference of morphology in the asexual cycle and no difference of growth rate compared to a wild-type strain.

Amino Acid Sequence↗
PubMed1993

Characterization of four new cell lines derived from small-cell gastrointestinal carcinoma.

Four human small-cell gastrointestinal carcinoma cell lines were established from tumor tissues of patients with esophageal, gastric or rectal cancer, and were studied morphologically and biochemically in comparison with small-cell lung carcinoma (SCLC) cell lines and common gastric cancer cell lines. Cells from all the small-cell gastrointestinal carcinoma lines were as small as classic SCLC cells and had characteristic neurosecretory granules. Cells from only one line grew as tightly packed spherical aggregates of floating cells, and those of the other 3 grew attached to substrate. Although high levels of creatine kinase brain isoenzyme (CK-BB) were detected in all 4 cell lines, 2 of them showed low levels of aromatic L-amino-acid decarboxylase and 3 had low levels of neuron-specific enolase (NSE). None of the lines showed simultaneous elevation of enzymes. C-myc, N-myc, and L-myc were not amplified in any of the cell lines, but c-myc mRNA was expressed in 2 lines. Our findings indicate that all small-cell gastrointestinal carcinoma cells examined belong to the variant type which is used in the classification of SCLC. Furthermore, the ECC18 line, derived from esophageal cancer, seemed to be of true endocrine cell origin, while the 3 other small-cell gastrointestinal carcinoma lines seemed to arise via neoplastic neometaplasia from adenocarcinoma cells to endocrine cells.

Aged↗
PubMed1993

Differential production of interleukin 6 in human osteosarcoma cells and the possible effects on neoplastic bone metabolism.

Interleukin 6 (IL-6) exerts well-established effects on cells of the immune system as well as on various other cell types. We have investigated the effects of IL-6 produced by human osteosarcoma cells on tumor cells from two clonal human osteosarcoma cell lines, KSU.C3 and NOS-1.C8. We were unable to identify any effects of IL-6 such as cell proliferation, alkaline phosphatase activity, osteocalcin production, or collagen synthesis on the bone-forming phenotypes. However, the KSU.C3 cell line, which showed a little osteoid and no bone formation and was accompanied by a few osteoclasts in the xenografted tumors, produced high levels of IL-6, the production of which was quickly and easily stimulated by various agents. On the other hand, the NOS-1.C8 cell line, which formed abundant osteoid or bone and was accompanied by no osteoclasts in the xenografted tumors, produced no detectable levels of IL-6 without stimulation, and the production of IL-6 in response to IL-1 beta was slower. Our data suggest that IL-6 produced by osteosarcoma cells does not play an important role in bone formation, but may mediate osteoclastic bone resorption.

Alkaline Phosphatase↗
PubMed1993

Interleukin 6-producing malignant mesothelioma.

Systemic amyloidosis of the amyloid A (AA) type, is occasionally associated with various neoplasms, but the cause is still unclear. We obtained interleukin 6 (IL-6)-producing cells designated YO from a primary culture of a malignant peritoneal mesothelioma of epithelial type obtained from a 62-year-old woman. Post mortem examination revealed that the patient had systemic amyloidosis of the AA type. The supernatant media of YO cells, as well as recombinant human IL-6, successfully induced nonneoplastic liver cells to produce serum AA (SAA). Our data suggest that IL-6 produced by the tumor cells may have played an important role in the paraneoplastic syndrome of AA amyloidosis in this patient.

Amyloidosis↗
PubMed1993

alpha-Fetoprotein producing gastric carcinomas: a comparative study of three different subtypes.

Nine cases of gastric carcinoma with excessive production of alpha-fetoprotein (AFP) were analyzed morphologically, histochemically and biochemically. Consequently, it was proposed that AFP-producing gastric carcinomas should be divided into three subtypes: (i) hepatoid type; (ii) yolk sac tumor-like type; and (iii) fetal gastrointestinal type. The data from the study suggested that the hepatoid type and the yolk sac tumor-like type are derived from liver cell metaplasia and yolk sac cell metaplasia of common poorly differentiated medullary adenocarcinoma, respectively. The fetal gastrointestinal type seemed to be a result of the imitation of fetal gastrointestinal epithelium by common tubular adenocarcinoma. The hepatoid type was also the most common in the file of AFP-producing gastric carcinoma. Unfortunately, most of the hepatoid types seemed to be highly malignant.

Aged↗
PubMed1993

Early stage of development in testicular choriocarcinomas.

Choriocarcinoma is the most malignant among germ cell tumors in the testis. However little is known about the early stage of its development. To understand the development of testicular choriocarcinomas, twenty cases of testicular choriocarcinoma were studied histologically and immunohistochemically. It was found that in the early stage of development, choriocarcinomas imitate the morphologic or functional differentiation of normal trophoblasts. It was also found that some choriocarcinomas regress spontaneously in the early stage. The majority of choriocarcinomas seemed to develop by first going through the embryonal carcinoma phase. However, there were some choriocarcinomas that showed no relationship with embryonal carcinoma.

Choriocarcinoma↗
PubMed1992

Functioning ovarian carcinoids induce severe constipation.

Five patients with ovarian carcinoid who had severe constipation for a long period preoperatively showed marked reduction of this symptom postoperatively. Because this phenomenon was believed to be caused by some biologically active substance rather than a mechanical effect of the tumor, reactivity to 17 amine and peptide hormones was studied immunohistochemically in these patients. Numerous peptide YY (PYY)-positive cells were detected, with PYY-positive cells representing more than 50% of all carcinoid tumor cells in each patient. PYY, which has a pharmacologic inhibitory action on intestinal motility, was presumably the cause of the constipation in these patients.

Adult↗
PubMed1992

Three human osteosarcoma cell lines exhibiting different phenotypic expressions.

to elucidate the differences in histological features and biological behavior of osteosarcomas, three human osteoblastic-type osteosarcomas were studied in vitro and in nude mice. The secretory processing and extracellular fiber formation of type I collagen proved to be the most important factor in bone formation in the osteosarcomas. Alkaline phosphatase also seemed to be important. However, we were unable to find any particular protooncogene abnormalities which could have been implicated in the occurrence or biological behavior of these osteosarcomas.

Alkaline Phosphatase↗
PubMed1992

Percutaneous introduction of left atrial cannula for left heart bypass: utility of biplane transesophageal echocardiographic guidance for transseptal puncture.

For introduction of a left atrial (LA) cannula by the transseptal puncture technique, we examined the feasibility of using biplane transesophageal echocardiography (B-TEE). A transseptal puncture was performed on 15 patients (3 male; 12 female; mean age, 48.9 +/- 11.2 years) by B-TEE guide during percutaneous transvenous mitral comissurotomy (PTMC). The entire Brocken-brough needle and the position of its tip were clearly observed in the right atrium by a longitudinal image of B-TEE in all patients (100%), and in 2 (13%) of them also by the transverse image of B-TEE. The puncture was about 1 cm caudal from the center of the fossa ovalis to avoid any large residual atrial septal defect. After transseptal puncture, a Mullin's sheath (7 Fr) and a dilator (14 Fr) were inserted into the left atrium in order, and then an Inoue's balloon catheter (12 Fr) was introduced without difficulty into the left atrium in all patients. With contrast injection, the position of the sheaths's tip was clearly confirmed by B-TEE. Left heart bypass support (left atrial-femoral artery bypass or AAB) was performed on 2 patients after percutaneous introduction of the LA cannula using this technique, and both were successfully supported and survived. With B-TEE guidance, the Brockenbrough atrial septal puncture and introduction of the LA cannula into left atrium can be performed easily. Thus, percutaneous left heart bypass can be set up quickly and safely even in an intensive care unit or outpatient emergency room without radiographic guidance.

Adult↗
PubMed1992

A case of hypersensitivity syndrome resembling Langerhans cell histiocytosis during phenobarbital prophylaxis for convulsion.

The case of a two-year-old girl with generalized histiocytosis, probably induced by phenobarbital, is reported. Symptoms, including intermittent fever, systemic lymphadenopathy, maculopapular skin eruption and hepatosplenomegaly, suggested Langerhans cell histiocytosis. Laboratory examinations revealed leukocytosis with lymphocytosis and eosinophilia and a high LDH serum level, while GOT and GPT were within normal ranges. Cytological studies of lymph node and pleural effusion specimens revealed proliferation and infiltration of Langerhans cell histiocytes with eosinophilia. No histiocyte proliferation was observed in the bone marrow or skin. The clinical manifestations shown by the patient were, however, transient, and improved spontaneously after the discontinuation of phenobarbital. The case was considered to be one of phenobarbital hypersensitivity syndrome based on clinical course and laboratory findings. The mechanism and differential diagnosis of the syndrome are discussed.

Child, Preschool↗