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M Seki

Publications and source records attributed to M Seki.

At least 271 records · Page 15Linked to original sources
PubMed1992

[Intra-arterial infusion chemotherapy with side-hole catheter for primary and metastatic liver, bile duct, and pancreas cancers].

Dislodgement and obstruction of catheter inserted into the artery are great hazards for the hepatic artery infusion chemotherapy. To prevent dislodgement, a new Anthron-coated catheter with a side hole was applied for the treatment of 32 patients with primary and metastatic liver cancer, bile duct cancer and pancreas cancer. The tip of the catheter was advanced deep into the gastroduodenal artery, proper or right hepatic artery, or splenic artery. Anti-cancer drugs were administered through the proximal side hole for targeting cancer. If necessary, the gastroduodenal artery was occluded with a metal coil. No dislodgement or obstruction of the catheter was noticed in the 32 patients thus treated. The new Anthron-coated catheter with a side hole proved to be useful for prevention of catheter dislodgement and accomplishment of long-term intra-arterial infusion chemotherapy.

Aged↗
PubMed1991

Molecular cloning of the cytochrome aa3 gene from the archaeon (Archaebacterium) Halobacterium halobium.

A novel aa3-type cytochrome oxidase from the extremely halophilic archaeon, Halobacterium halobium, differs significantly from those of other prokaryotic and eukaryotic cytochrome oxidases (Fujiwara, T., Fukumori, Y., and Yamanaka, T. (1989) J. Biochem. 105, 287-292). In the present study, we cloned and sequenced the gene which encodes the cytochrome aa3 by using the polymerase chain reaction methods. The deduced amino acid sequence of subunit I of H. halobium cytochrome aa3 was more similar to that of subunit I of the eukaryotic cytochrome (44%, maize mitochondria) than that of the cytochrome from other bacteria (36%, Paracoccus denitrificans). The consensus sequence in putative metal binding residues is well-conserved also in H. halobium cytochrome aa3.

Amino Acid Sequence↗
PubMed1991

Glycolipid changes in murine myelogenous leukemias: neutral glycolipids as markers for specific populations of leukemias.

We have studied the glycolipid composition of six different murine myelogenous leukemias as well as that of T-cell leukemias and normal spleen cells. Neutral and acidic lipid fractions were isolated by column chromatography on DEAE-Sephadex and analyzed by high-performance thin-layer chromatography (HPTLC) and an HPTLC overlay method. Murine myelogenous leukemias were found to contain globo- and ganglio-series neutral glycolipids, e.g., glucosylceramide (Glc-cer), lactosylceramide (Lac-cer), globotriaosylceramide (Gb3), globoside (Gb4), Forssman glycolipid (Gb5), and asialo-GM1 (GA1). Monoblastic leukemia cells contained increased proportions of Gb3, Gb4, Gb5, and GA1. Monocytic and myelomonocytic leukemia cells contained increased proportions of Glc-cer and Lac-cer. Especially, Glc-cer accounted for approximately 60% of the total neutral glycolipids in monocytic leukemia cells. Gb3 was the major neutral glycolipid in reticulum cell neoplasm type A, and it accounted for approximately 75% of the neutral glycolipids. GA1 was the major neutral glycolipid in myeloblastic and granulocytic leukemia cells as well as T-cell leukemias. Especially, granulocytic leukemia cells contained predominantly GA1, and it accounted for approximately 80% of the total neutral glycolipids. The pattern of gangliosides in myelogenous leukemias was more complex when compared with that of the neutral glycolipids; murine myelogenous leukemias contained at least 13 gangliosides, including such major gangliosides as GM1, GM1b containing N-acetyl neuraminic acid and N-glycolyl neuraminic acid, and Ga1NAc-GM1b. Alterations of glycolipid composition in murine myeloid leukemias may be associated with cellular differentiation and maturation, and therefore these characteristic glycolipid species may be regarded as markers for specific populations of leukemia cells.

Animals↗
PubMed1991

Molecular cloning of phosphofructokinase 1 gene from a thermophilic bacterium, Thermus thermophilus.

Phosphofructokinase 1 (PFK1) from Thermus thermophilus differs from other bacterial PFKs in that it is regulated by effector-induced reversible tetramer-dimer conversion rather than conformational change alone. We have cloned its gene and the deduced amino acid sequence was compared with that of other PFKs. While almost all amino acid residues involved in substrate binding sites, which are assigned from crystal structures of other PFKs, are well conserved, some possibly important changes are found at subunit interfaces.

Amino Acid Sequence↗
PubMed1991

Suppression of tumorigenicity in human colon carcinoma cells by introduction of normal chromosome 5 or 18.

Development of colon carcinomas can be associated with allelic deletions on several chromosomes, including 5q and 18q. The APC gene on 5q and the DCC gene on 18q have been identified as potential tumour suppressor genes, whose suppression contributes to colon carcinogenesis. To investigate the role of genes in these deleted regions, we have now introduced a single normal human chromosome into a human colon carcinoma cell line, COKFu, through microcell hybridization. Several clones of hybrid cells containing normal chromosome 5, and others containing normal chromosome 18, were obtained. The morphology of the hybrid cells was markedly altered: the hybrids with chromosome 5 exhibited a closely packed polygonal morphology, and the hybrid cells with chromosome 18 were flattened. The cloning efficiency of the hybrid cells in soft agar was reduced from 0.46 to 0% of that of the parental carcinoma cells, and the tumorigenicity of these hybrid cells in athymic nude mice was completely suppressed. The growth properties of the hybrid cells with chromosome 11 were not substantially changed. These results strongly suggest that the genes on normal chromosome 5 and 18 function as tumour suppressors in colon carcinogenesis.

Animals↗
PubMed1991

Response of newly established mouse myeloid leukemic cell lines to MC3T3-G2/PA6 preadipocytes and hematopoietic factors.

Some mouse myeloid leukemias induced by X-irradiation and serially transplanted into syngenic mice do not proliferate in vitro even in the presence of hematopoietic factors. To examine whether such leukemic cells can proliferate in response to stromal cells, we cocultured them with MC3T3-G2/PA6 (PA6) preadipocytes, cells that can support the growth of hematopoietic stem cells. All leukemias developed into in vitro cell lines, showing a dependence on contact with the PA6 cells. Two cell lines responded to none of the known hematopoietic factors including interleukin-3 (IL-3), IL-4, IL-5, IL-6, GM-CSF, G-CSF, M-CSF, and Epo. These results demonstrate that the mechanism of the action of PA6 cells is different from that of any of the known hematopoietic factors, and that, because these two leukemic cell lines retained the ability to grow in vivo, responsiveness to the known hematopoietic factors is not essential for the leukemic cell growth in vivo. Furthermore, all leukemic cell lines could respond also to the preadipocytes fixed with formalin, paraformaldehyde, or glutaraldehyde, suggesting that some molecule(s) associated with the surface of PA6 cells or with extracellular matrix secreted by the preadipocytes is responsible for the leukemic cell growth.

Adipose Tissue↗
PubMed1991

Murine acute leukemia cell line with megakaryocytic differentiation (MK-8057) induced by whole-body irradiation in C3H/He mice: cytological properties and kinetics of its leukemic stem cells.

Five cases of murine leukemia with megakaryocytic differentiation were observed among the 417 cases of radiation-induced leukemias which developed in 30% of C3H/HeMs mice exposed at 8 to 10 weeks to 0.5 to 5 gy total body irradiation. Cells from individual leukemic colonies in the spleen of the irradiated mice, and cells from colonies in methylcellulose (MC) culture in vitro, derived from one of these leukemias, MK-8057, were injected into mice; both types of cells caused the deaths of the recipient mice by inducing the same type of leukemia. MK-8057 can be maintained in Dexter-type liquid culture with a feeder layer of irradiated bone marrow cells. There was a linear reciprocal relationship between the increasing number of MK-8057 cells injected versus the survival of the recipient mice. A reciprocal relationship also was seen between an increasing number of leukemic stem cells, corresponding to the number of MK-8057 cells, and the survival of mice injected with MK-8057. Giant nuclear megakaryocytes developed during the course of colony growth in the spleen as they did in the MC culture. Such megakaryocytes were acetylcholinesterase positive, whereas leukemic cells in the peripheral blood showed no sign of platelet production nor of a positive reaction to acetylcholinesterase. Cells maintained in culture were entirely positive in platelet glycoprotein IIb/IIIa when anti-human antibody was used. The larger cells in a splenic cell suspension derived from a moribund mouse were separated and enriched by velocity sedimentation using centrifugal elutriation (CE), and then subjected to flow cytometry using propidium iodide staining. Cells with up to 32N-DNA content were detected. After separating MK-8057 by counter-flow CE, the larger cell fraction (mode at 540 microns3) produced more leukemic colonies when injected into irradiated mice than did the small cell fraction (mode at 240 microns3). A higher percent of the larger cell fraction (61.9%) was killed by the addition of tritiated thymidine cytocide than in the smaller cell fraction (14.9%). Thus, the smaller cell fraction is considered to have more leukemic spleen colony-forming units (L-CFU-s) in the resting state.

Animals↗
PubMed1991

Transient expression of beta-glucuronidase in Arabidopsis thaliana leaves and roots and Brassica napus stems using a pneumatic particle gun.

Successful transient expression of beta-glucuronidase (GUS) in Arabidopsis thaliana leaves and roots and Brassica napus stems was obtained after gene delivery with a pneumatic particle gun driven by compressed air. Effects of the pneumatic pressure used to accelerate the particles (accelerating pressure; 85 to 200 kg/cm2) and of preculture periods of plant tissues (0 to 6 days) on the efficiency of gene delivery were studied. In A. thaliana leaves, best results were obtained at 115 kg/cm2 of accelerating pressure and 3 days of preculture. In A. thaliana roots, the optimum was at 200 kg/cm2 of accelerating pressure and 3 days of preculture. These results indicate that both preculture period and accelerating pressure are vital factors that determine the efficiency of gene delivery by particle gun.

Atmospheric Pressure↗
PubMed1991

Clinical evaluation of endoscopic hemostasis for bleeding gastric and duodenal ulcers.

The present study shows the excellent efficacy of endoscopic hemostatic therapy by ethanol injection. At the same time, the results emphasize the significant efficacy of intensive pharmaceutical treatment for peptic ulcer patients with clinical symptoms of hematemesis and/or melena. Concerning endoscopic hemostatic therapy, we prefer ethanol injection therapy to most other methods, such as laser irradiation, microtase or heat probe, because the ethanol injection method is the most simple, inexpensive, safe, technically easy, can be performed any time and in any place, and is more effective than other methods. In rare cases where direct ethanol injection into the exposed blood vessels is difficult, we do not hesitate to select other contact methods such as heat probe or microtase.

Endoscopy, Digestive System↗
PubMed1991

Gallium-67 citrate scintigraphy in the pre-operative evaluation of soft tissue tumors of the extremities.

We conducted a study of 90 patients with soft tissue tumor in their arms or legs, in order to determine the usefulness of scintigraphy with gallium-67 citrate as a diagnostic means. All patients had adequate scan images, and tumor tissues had been histologically confirmed by surgical resection. The subjects consisted of 19 patients with malignant tumors, 55 patients with benign tumors, and 16 patients with other disorders in which soft tissue tumor-like lesions occurred. When the activity of the tumor was more than the activity of the normal region of the contralateral extremity, it was estimated to be positive. The positive rate was found in 78% (15/19) of patients with malignant tumors, in 25% (14/55) of patients with benign tumors and in 31% (5/16) of patients with other disorders. Classified by diseases, high positive rates were observed in liposarcoma, leiomyosarcoma, malignant lymphoma, neurinoma, extra-abdominal desmoid and sarcoidosis. Out of 7 patients in which the activity of the tumor was equal to, or higher than that of the liver, 6 patients had malignant tumors and one patient was diagnosed as having an abscess. It seemed possible to distinguish between liposarcoma and lipoma by means of a gallium-67 scan. Furthermore, the gallium-67 scan was useful in detecting lesions of sarcoidosis as well as in evaluating the response to treatment.

Adolescent↗
PubMed1991

Further evaluation of one-point microcapsule agglutination test for diagnosis of leptospirosis.

A total of 100 serum samples including 22 acute phase sera and 39 paired sera collected from clinically diagnosed cases of leptospirosis in Ming-shan County, Sichuan Province, China were examined by the one-point microcapsule agglutination test (MCAT), which was developed in Japan, and by conventional microscopic agglutination tests (MAT). The one-point MCAT is more reactive to IgM antibody than MAT and is superior in detecting antibodies in the early stages of the disease.

Acute Disease↗
PubMed1991

Submucosal dissection of the esophagus: a case report.

A 38-year-old male was admitted to our hospital complaining of dysphagia, sore throat and fever. An upper GI series revealed a "double-barrelled" esophagus. Endoscopic examination of the esophagus showed multiple ulcers and mucosal bridges resulting from laceration of the submucosal layer. An acute ulcer of the stomach was also found. Fasting and total parenteral nutrition for several weeks failed to bring about any changes in the endoscopic findings. As treatment, the mucosal bridges throughout the esophagus were divided with a diathermy knife under endoscopic control. Soon after the procedure, the patient's symptoms disappeared completely, and the massive dissection of the esophagus had improved except for slight depressions.

Adult↗
PubMed1991

[Leiomyosarcoma of the esophagus associated with pulmonary edema by the compression of the left atrium].

Leiomyosarcoma of the esophagus is a rare neoplasm. We reported a very rare case of esophageal leiomyosarcoma associated with pulmonary edema by the compression of the left atrium. A 67-year-old man was admitted with a 3-month history of chest pain, exertional dyspnea and dysphagia. Chest X-ray computed tomography showed posterior mediastinal tumor. Esophageogastroscopy and fiberoptic bronchofiberscopy showed no direct invasion of the tumor. By echocardiography, the left atrium was found to be compressed by the tumor and pulmonary hypertension (58/25 mmHg) and increased pulmonary wedge pressure (25 mmHg) was present. Open biopsy specimen demonstrated elongated cells suggestive of sarcoma. At autopsy, the tumor was confirmed to be leiomyosarcoma and to be originated from the lower esophagus.

Aged↗
PubMed1991

Characterization of a new human apolipoprotein A-I Yame by direct sequencing of polymerase chain reaction-amplified DNA.

A new genetic variant apolipoprotein (apo), A-I Yame, was discovered during screening for apoA-I genetic variants with isoelectric focusing gel electrophoresis. To investigate the structural abnormality of apoA-I Yame, we amplified the apoA-I gene isolated from the proband's peripheral blood leukocytes with the polymerase chain reaction (PCR) method and directly sequenced these PCR fragments. ApoA-I Yame was found to have aspartic acid (GAC) substituted by tyrosine (TAC) at residue 13. We also identified this substitution by an automated DNA sequencer. This substitution was confirmed with amino acid sequencing of the isolated apoA-I Yame by Immobiline gel electrophoresis. This combined method, direct PCR from genomic DNA-derived individual peripheral blood leukocytes and subsequent direct sequencing, can be used to identify the entire sequence of apoA-I in a short period of time. Furthermore, with this method, it is possible to identify both alleles in heterozygous individuals.

Alleles↗