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Y Kitamura

Publications and source records attributed to Y Kitamura.

At least 37 records · Page 2Linked to original sources
PubMed1992

[An evaluation of perioperative and continuous infusion of tegafur as surgical adjuvant chemotherapy of resected gastric cancer].

Perioperative continuous intravenous infusion of Tegafur (FT) seems theoretically an effective adjuvant chemotherapy for patients with gastric carcinoma. Then we estimated the clinical effect of this therapy on the survival of patients who had undergone curative (Stage I, II, III) and non-curative (Stage IV) resection of a primary gastric carcinoma. One hundred fifty patients received chemotherapy and two hundred thirty-seven were observed. Results showed a significant difference in survival curves of Stage I (p less than 0.01) and Stage III (p less than 0.01). The 5-year survival rate was 100% for the adjuvant therapy arm and 82% for the observation arm in Stage I. In stage III, the survival curve of both arms was similar from the beginning to the 5th year, but the 7-year survival rate was 53% and 39%, respectively. There was no serious side effect of chemotherapy. These results demonstrate that this chemotherapy regimen is beneficial and recommendable as a perioperative adjuvant chemotherapy for resected gastric cancer in which the cancer cells were almost removed.

Chemotherapy, Adjuvant↗
PubMed1991

Anemia and mast cell depletion in mutant rats that are homozygous at "white spotting (Ws)" locus.

Mice possessing two mutant alleles at the W or Sl locus are anemic and deficient in mast cells. These mouse mutants have black eyes and white hair. Because homozygous mutant rats at the newly found white spotting (Ws) locus were also black-eyed whites, the numbers of erythrocytes and mast cells were examined. Suckling Ws/Ws rats showed a severe macrocytic anemia and were deficient in mast cells. When bone marrow cells of normal (+/+) control or Ws/Ws rats were injected into C3H/He mice that had received cyclophosphamide injection and whole-body irradiation, remarkable erythropoiesis occurred in the spleen of +/+ marrow recipients but not in the spleen of Ws/Ws marrow recipients. When skin pieces of Ws/Ws embryos were grafted under the kidney capsule of nude athymic rats, mast cells did develop in the grafted skin tissues. Therefore, the anemia and mast cell deficiency of Ws/Ws rats were attributed to a defect of precursors of erythrocytes and mast cells. Because the magnitude of the anemia decreased and that of the mast cell deficiency increased in adult Ws/Ws rats, this mutant is potentially useful for investigations about differentiation and function of mast cells.

Anemia↗
PubMed1991

6-Deoxy-D-talan and 6-deoxy-L-talan. Novel serotype-specific polysaccharide antigens from Actinobacillus actinomycetemcomitans.

Serotype-specific polysaccharide antigens from Actinobacillus actinomycetemcomitans ATCC 29523 (serotype a) and NCTC 9710 (serotype c) were extracted from whole cells by autoclaving and purified by ion-exchange chromatography and gel filtration. Analysis of component sugars by gas-liquid chromatography-mass spectrometry, high performance liquid chromatography, and NMR together with optical rotation data showed that the serotype a antigen was composed solely of 6-deoxy-D-talose, whereas the serotype c antigen consisted of 6-deoxy-L-talose. Structural analysis indicated that both of these antigens were composed of closely related repeating units, -3)-6-deoxy-alpha-D-Talp-(1-2)-6-deoxy-alpha-D-Talp-(1-(sero type a) and -3)-6-deoxy-alpha-L-Talp-(1-2)-6-deoxy-alpha-L-Talp-(1-(sero type c). 1H and 13C NMR analysis showed that both of these serotype antigens contained one acetyl group/2 sugar residues. These acetyl groups localized at the O-2 position of 3-linked 6-deoxy-D-talose (serotype a) or O-4 position of 3-linked 6-deoxy-L-talose residues (serotype c), respectively. These results coupled with our previous findings on the serotype b antigen (Amano, K., Nishihara, T., Shibuya, N., Noguchi, T., and Koga, T. (1989) Infect. Immun. 57, 2942-2946) showed that the serotype antigens from A. actinomycetemcomitans are a group of novel polysaccharides with structural features closely related biosynthetically.

Actinobacillus↗
PubMed1991

Illegitimate recombination in a bovine papillomavirus shuttle vector: a high level of site specificity.

Recombination in a bovine papillomavirus shuttle vector carrying direct repeats of Moloney murine leukemia virus LTR sequence was examined. Differently from similar vectors carrying direct repeats of SV40 polyA addition signal or neomycin resistance gene, the vector exhibited no homologous recombination between the repeats. Instead, illegitimate recombination took place. There were two major types of recombination products from the restriction cleavage pattern. The plasmids in independent cellular clones belonging to the same recombination type shared the identical crossover point. Thus, in this plasmid, illegitimate recombination occurred at preferential sites involving exactly the same sequences.

Animals↗
PubMed1991

In vitro "progression" of bovine papillomavirus-transformed cells: loss of contact sensitivity after multiple rounds of selection.

The transformed phenotype of C127 cells harboring bovine papillomavirus shuttle vector pdBPVMMT neo(342-12) was suppressed by direct contact with untransformed C127 cells. By repeated selections of rare foci developing on untransformed cell monolayers, we obtained a cellular clone of BPV transformants which formed foci on the untransformed C127 cells as efficiently as on plastic surface. The BPV genome in the mutant cells showed extensive genetic rearrangements, duplication of upstream regulatory region and deletion of pBR322-derived sequence and its flanking. There was an increase in BPV-transformant in contact with the untransformed C127 cells resulted in a marked reduction of the BPV transcripts, while in the case of the mutant transformant the reduction was much slighter. This indicates that the transcription level of the BPV genome was controlled by a cell-cell contact signal.

Animals↗
PubMed1991

Nerve growth factor induces development of connective tissue-type mast cells in vitro from murine bone marrow cells.

The effect of nerve growth factor (NGF) on proliferation/differentiation of mast cells was investigated in vitro. Although NGF alone neither supported colony formation of bone marrow-derived cultured mast cells (BMCMC) nor induced development of mast cell colonies from nonadherent bone marrow cells (NBMC), addition of NGF to the suboptimal dose of interleukin 3 (IL-3) significantly increased the numbers of mast cell colonies produced by BMCMC or NBMC in methylcellulose. When stimulated by IL-3 alone, cells in mast cell colonies were not stained by berberine sulfate, a fluorescent dye. In contrast, mast cells developing in methylcellulose cultures obtaining both IL-3 and NGF were stained by berberine sulfate. The fluorescence was abolished by the treatment of heparinase but not of chondroitinase ABC, suggesting that mast cells stimulated by IL-3 and NGF produced and stored heparin proteoglycan. The histamine content of BMCMC maintained by IL-3 was also increased by addition of NGF. Since BMCMC showed mucosal mast cell-like phenotype, NGF appeared to induce the phenotypic change to connective tissue-type mast cells (CTMC). In the culture containing BMCMC, 3T3 fibroblasts, and IL-3, the phenotypic change of BMCMC to CTMC was observed as well. Since NGF was detected in this coculture and since addition of anti-NGF monoclonal antibody suppressed the phenotypic change, NGF produced by fibroblasts appeared to induce the phenotypic change. Neither BMCMC alone nor IL-3 alone increased the concentration of NGF. Therefore, there is a possibility that BMCMC stimulated by IL-3 may induce the production and/or release of NGF by fibroblasts.

Animals↗
PubMed1991

Homologous recombination in bovine papillomavirus shuttlevecter; effect of relative orientation of substrate sequences.

Relative orientation of recombination substrates, neo gene, strongly influenced homologous recombination events in a bovine papillomavirus shuttle vector. Between direct repeats, recombination occurred at a high frequency while between inverted repeats, it was rare. Double strand break near the mutation site increased the recombination frequency between inverted repeats but not between direct repeats. Formation of long heteroduplex as a recombination intermediate may explain this apparently paradoxical phenomenon.

Base Sequence↗
PubMed1991

Anaesthetic management of phaeochromocytoma associated with tricuspid atresia.

The anaesthetic management of a patient with phaeochromocytoma, tricuspid atresia and pulmonary vascular stenosis is reported. The patient received no preoperative preparation with adrenergic blockers. Anaesthesia was induced and maintained with fentanyl, diazepam and sevoflurane. Intraoperative blood pressure was controlled with sodium nitroprusside, sevoflurane, phentolamine, and propranolol. For hypotension after resection of the tumour norepinephrine was required. This patient did not have a systemic to pulmonary shunt procedure performed, so the maintenance of pulmonary blood flow in the presence of haemodynamic instability during operation for phaeochromocytoma was a major concern. Monitoring of oxyhaemoglobin saturation (SpO2) with a pulse oximeter was considered to be useful because SpO2 may reflect pulmonary flow. During serious haemodynamic disturbances due to the manipulation of the tumour, the heart rate was inversely correlated with SpO2, but the relationship between mean arterial pressure and SpO2 was weak. Therefore, control of heart rate appeared to be more important than control of blood pressure in this case.

Adolescent↗
PubMed1991

Effect of dexamethasone on uterine cell death.

Oestrogen, progesterone and androgen inhibit uterine cell death after the depletion of oestrogen. In the present study, we investigated effects of glucocorticoid on death of mouse uterine cells. Castrated female mice were given a daily injection of 17 beta-oestradiol (0.2 microgram/mouse/day) for 3 days, and then an injection of 5'-[125I]iodo-2'-deoxyuridine ([125I]IdUrd) to label DNAs of uterine cells with 125I. Mice were killed at intervals during subsequent treatments, and the retention of [125I]IdUrd incorporated into the whole uterus was determined. On subsequent injection of vehicle only, the 125I-radioactivity retained in the whole uterus rapidly decreased. Injections of dexamethasone (50 micrograms/mouse/day) reduced the loss of 125I-radioactivity slightly but significantly. Dexamethasone also showed synergistic effects on the retention of 125I-radioactivity when it was daily injected together with 17 beta-oestradiol, progesterone or 5 alpha-dihydrotestosterone. The present results suggest that glucocorticoid may affect the processes involved in the uterine cell death, in a manner such as inhibiting the uterine cell death or delaying the removal of DNAs of dead cells from the uterus.

Animals↗
PubMed1991

Fibroblast-dependent differentiation/proliferation of mast cells.

Fibroblast-dependent differentiation and proliferation of mast cells were reviewed from the viewpoint of mast cell-deficient mutant animals. Mice of W/Wv, Sl/Sld or mi/mi genotype are deficient in mast cells. However, since T cell-dependent differentiation and proliferation of mast cells are intact in these mutant mice, mast cells do develop when bone marrow cells of these mutant mice were cultured in the presence of T cell-derived growth factors. Cultured mast cells (CMC) of W/Wv mice cannot receive the proliferative stimulus from fibroblasts whereas fibroblasts derived from Sl/Sld embryos cannot provide normal (+/+) CMC with the proliferative stimulus. The W locus encodes a tyrosine kinase receptor and the Sl locus the ligand for the receptor. Although +/+ CMC acquire the phenotype resembling connective tissue-type mast cells when cocultured with fibroblasts in medium containing T cell-derived growth factors, mi/mi CMC do not. We recently found a mast cell-deficient mutant of rats. Biological features of the mast cell-deficient rats were very similar to those of W/Wv mice. The mast cell-deficient mutant animals are invaluable tools for investigations of differentiation/proliferation and functions of mast cells.

Animals↗
PubMed1991

Survey of Hanganutziu and Deicher antibodies in operated patients.

The appearance of Hanganutziu and Deicher (HD) antibody in the sera of patients suffering from various diseases, including malignancies of some organs and liver disorders, was investigated by enzyme-linked immunosorbent assay using N-glycolylneuraminyl-lactosylceramide (HD3) and 4-O-acetyl-HD3 as the antigenic molecules. More than 25% of sera from patients suffering from malignancies, cholelithiasis and liver cirrhosis had HD antibody, whereas none of 41 sera from healthy persons had HD antibody. The percentage of HD antibody-positive patients was similar in stages I, II and III of gastric cancer and recurrence cases. Antibody titers of the positive patients in each stage were also not different from those in each other stage. These results indicated that HD antigenic expression on cancerous tissue is not dependent on the cancerous malignancy. The HD antibody level was elevated after surgical removal of cancerous tissues in 5 of 6 patients examined, indicating that tumor growth absorbed the serum antibody. Serum antibody against 4-O-acetyl-HD3 was detected independently of HD3 antibody in some cases; however, in most cases, correlation between the two antibody titers was observed.

Aged↗
PubMed1991

Biologically active kit ligand growth factor is produced by mouse Sertoli cells and is defective in SId mutant mice.

In order to define the role of Kit ligand (KL) growth factor encoded at the mouse steel (SI) locus in spermatogenesis, we have examined its production in Sertoli cells. As a measure KL growth factor bioactivity, the ability to support proliferation and maintenance of mast cells was used in co-culture with primary mouse Sertoli cells. On the sertoli cells derived from +/+ and Wv/Wv mice, +/+ mast cells proliferated and were supported for more than 2 weeks, but not W/Wv mast cells. In contrast, Sertoli cells from SId/SId mice could not support +/+ mast cell proliferation under similar conditions. The supportive effect required close-range interaction of Sertoli cells with cultured mast cells. These results indicate that Sertoli cells derived from +/+ and Wv/Wv but not SId/SId mutant mice produce biologically active KL growth factor as a membrane-bound form. The biologically active KL of Sertoli cells may also play an important role in germ cell growth and differentiation.

Animals↗
PubMed1991

Effects of nebracetam (WEB 1881 FU), a novel nootropic, as a M1-muscarinic agonist.

We here investigated the effects of nebracetam (WEB 1881 FU 4-aminomethyl-1-benzylpyrrolidin-2-one-hemifumarate), a novel pyrrolidinone nootropic, on the rise of intracellular Ca2+ concentration ([Ca2+]i) in Jurkat cells, a human leukemic T cell line. Nebracetam induced a rise of [Ca2+]i in the medium with 1 mM Ca2+ and without Ca2+ (plus 1 mM EGTA). The nebracetam-induced [Ca2+]i rise was blocked by atropine greater than pirenzepine greater than AF-DX 116. From these results, nebracetam seems to act as an agonist for human M1-muscarinic receptors.

Animals↗
PubMed1991

Effects of bifemelane hydrochloride, a brain function improver, on muscarinic receptors in the CNS of senescence-accelerated mouse.

Senescence-accelerated mouse (SAM-P/8) is known as a murine model of aging and memory dysfunction, compared with control mouse (SAM-R/1). In the hippocampus of 9-month-old SAM-P/8, the Bmax of [3H]QNB binding was decreased compared with that of SAM-R/1 at the same age. Single and repeated administrations of bifemelane to SAM-P/8 induced an increase in the Bmax of [3H]QNB binding in the hippocampus. From these results, bifemelane seems to exert pharmacological effects through possible activation of the cholinergic system in the hippocampus of SAM.

Aging↗
PubMed1991

Bone marrow-derived cultured mast cells and peritoneal mast cells as targets of a growth activity secreted by BALB/3T3 fibroblasts.

When fibroblast cell lines were cultured in contact with bone marrow-derived cultured mast cells (CMC), both NIH/3T3 and BALB/3T3 cell lines supported the proliferation of CMC. In contrast, when contact between fibroblasts and CMC was prohibited by Biopore membranes or soft agar, only BALB/3T3 fibroblasts supported CMC proliferation, suggesting that BALB/3T3 but not NIH/3T3 cells secreted a significant amount of a mast cell growth activity. Moreover, the BALB/3T3-derived growth activity induced the incorporation of [3H]thymidine by CMC and the clonal growth of peritoneal mast cells in methylcellulose. The mast cell growth activity appeared to be different from interleukin 3 (IL-3) and interleukin 4 (IL-4), because mRNAs for these interleukins were not detectable in BALB/3T3 fibroblasts. Although mast cells are genetically deficient in tissues of W/Wv mice, CMC did develop when bone marrow cells of W/Wv mice were cultured with pokeweed mitogen-stimulated spleen cell-conditioned medium. Because BALB/3T3 fibroblast-conditioned medium (BALB-FCM) did not induce the incorporation of [3H]thymidine by W/Wv CMC, the growth activity in BALB-FCM appeared to be a ligand for the receptor encoded by the W (c-kit) locus. Because CMC and peritoneal mast cells are obtained as homogeneous suspensions rather easily, these cells may be potentially useful as targets for the fibroblast-derived mast cell growth activity.

Animals↗