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T Oyama

Publications and source records attributed to T Oyama.

At least 145 records · Page 8Linked to original sources
PubMed1995

Detection of CYP1A1 gene polymorphism using designed RFLP and distributions of CYP1A1 genotypes in Japanese.

Isoleucine (Ile)-valine (Val) polymorphism, which is caused by a point mutation from A to G in exon 7, is reported to be associated with an elevated risk of lung cancer among Japanese. Because CYP1A1 catalyzes bioactivation of environmental procarcinogens, such as benzo[a]pyrene, it is very important to study the clinical meaning of Ile-Val polymorphism using an epidemiological study. In an epidemiological study, easy, economical, rapid and reliable identification of the CYP1A1 genotype is necessary. The present study shows that the new method, designed restriction fragment length polymorphism (designed RFLP), can detect Ile-Val polymorphism of CYP1A1. The Ile-Val polymorphism detected using this new method was consistent with that found by the allele-specific PCR amplifications (ASA) method in six cases tested. This new method detected Ile-Val polymorphism of CYP1A1 using 240 healthy Japanese who lived in the northern Kyusyu region. The frequency of the genotypes was as follows: Ile/Ile 159 (66.2%); Ile/Val, 65 (27.1%); Val/Val, 16 (6.7%). The frequency of the Ile gene was 0.798 and that of the Val gene, 0.202. There was no difference in Ile-Val polymorphism based on sex or age. Racial differences influenced the distribution of this polymorphism, but Japanese regional differences did not. Since this new method, designed RFLP, is rapid, reliable and suitable for large-scale screening of polymorphisms, it may be used routinely to detect Ile-Val polymorphism of CYP1A1. Furthermore, it will help to evaluate the relationship between CYP1A1 polymorphism and individual sensitivity to xenobiotics that may affect the incidence of lung cancer.

Adult↗
PubMed1995

Frequent loss of the short arm of chromosome 9 in resected non-small-cell lung cancers from Japanese patients and its association with squamous cell carcinoma.

We analyzed 87 Japanese non-small-cell lung carcinomas (NSCLC) including 30 squamous cell, 51 adenocarcinomas and 6 large-cell carcinomas for loss of heterozygosity (LOH) on the short arm of chromosome 9, and we correlated our findings with clinicopathological features. We used four polymorphic microsatellite markers on 9p (interferon A gene, D9S171, D9S126, and D9S169), which flank the critical region (9p21-22) involved in lung cancer. We observed alterations of DNA sequences at 9p in NSCLC (27 of 82 informative cases or 33%). Concordance among the four markers was high (87%), indicating that the deletions often were relatively large. The 27 genetic alterations observed on 9p include 26 examples of LOH, 1 homozygous deletion, and 1 case with LOH and evidence of microsatellite alteration characterized by shift in band mobility. We noted a high frequency of LOH at 9p especially in squamous cell carcinoma (17 of 29 informative cases or 59%), and in poorly differentiated NSCLC (12 of 23 informative cases or 52%). There was no correlation between LOH at 9p and the other clinical parameters, including survival, gender, tumor size and the presence of regional or distant metastases. In contrast to other reports, we found only rare instances of homozygous deletions (1%) and microsatellite alteration showed as a mobility shift (1%). Our findings demonstrate that LOH at the short arm of chromosome 9 is correlated with squamous cell and poorly differentiated carcinomas in Japanese patients with NSCLC.

Base Sequence↗
PubMed1995

Opioidergic inhibition of capsaicin-evoked release of glutamate from rat spinal dorsal horn slices.

We investigated the effects of opioid agonists on the capsaicin-evoked release of glutamate from nociceptive primary afferent fibers of the rat (6-8 weeks) using a fluorometric on-line continuous monitoring system for glutamate. In the presence of 0.3 microM tetrodotoxin, the application of 3 microM capsaicin to spinal dorsal horn slices produced an evoked glutamate release (55.9 +/- 4.02 pmol.mg-1 protein, n = 15). DAMGO ([D-Ala2,N-Me-Phe4,Gly5-ol]enkephalin; 0.3-10 microM) and morphine (1-30 microM), mu-opioid agonists, produced a concentration-dependent reduction (approximately 85 and approximately 77% reduction, respectively) in the capsaicin (3 microM)-evoked release of glutamate. These inhibitory effects were significantly antagonized by naloxone (1 microM). DPDPE ([D-Pen2,5]enkephalin; 1-10 microM), a delta-opioid agonist, also reduced the capsaicin-evoked release in a concentration-dependent manner (approximately 59% reduction). Naltrindole (1 microM), a selective delta-antagonist, significantly antagonized the inhibitory effect of DPDPE (10 microM). In contrast, neither U-50,488H (1-10 microM) nor U-69,593 (10 microM), kappa-opioid agonists, had any effects on the evoked release of glutamate. These results suggest that mu-, and delta-opioid agonists modulate pain transmission in the spinal dorsal horn, at least in part, by inhibiting the release of glutamate from capsaicin-sensitive primary afferents.

3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cycloh↗
PubMed1995

Growth activity in hyperplastic and neoplastic human thyroid determined by an immunohistochemical staining procedure using monoclonal antibody MIB-1.

To increase our understanding of the basic biological mechanisms of thyroid diseases, growth activity (GA) in 232 thyroid lesions was determined by immunohistochemistry using monoclonal antibody MIB-1. The GA tended to be higher in hyperplastic lesions, adenomatous goiter (MIB-1-positive cell rate, 0.73%), and Graves' disease (1.68%) than in normal tissue (0.19%). The GA for differentiated thyroid carcinomas (2.00%) was much lower than for adenocarcinomas of other organs, such as breast, lung, stomach and colon (44.67%). Of the thyroid carcinomas, the highest GA was observed in undifferentiated carcinomas (32.67%), and follicular carcinomas (3.18%) showed a higher GA than papillary carcinomas (1.83%). There was no significant difference between the GA of follicular carcinomas and solid/trabecular adenomas, although widely invasive follicular carcinomas showed a higher GA than minimally invasive carcinomas. No significant correlations between GA and patient age, sex, and tumor diameter, metastasis, or histological features were observed in papillary carcinomas. Familial medullary carcinomas showed a higher GA than sporadic tumors. All latent papillary carcinomas had a very low GA. Our findings suggest that immunohistochemical investigation using the antibody MIB-1 contributes to the understanding of growth characteristics and biological activities in thyroid diseases.

Adenoma↗
PubMed1995

Immunocytochemical localization of the striatal enriched protein tyrosine phosphatase in the rat striatum: a light and electron microscopic study with a complementary DNA-generated polyclonal antibody.

The present study concerns the immunocytochemical localization of the striatal enriched protein tyrosine phosphatase in the rat striatum. A novel molecular biology technique allowed us to produce a complementary DNA-generated polyclonal antibody raised against the non-catalytic domain of the striatal enriched protein tyrosine phosphatase, which selectively recognized the striatal enriched protein tyrosine phosphatase protein with 46,000 mol. wt on western blots. Immunocytochemical analysis with the specific antibody revealed strong striatal enriched protein tyrosine phosphatase immunoreactivity in the striatum. Light microscopy showed striatal striatal enriched protein tyrosine phosphatase-immunopositive neurons to be of medium size (mean diameter of 14.4 microns), and to comprise approximately 80% of the total neuronal population in the striatum. These cells had round, triangular or polygonal cell bodies with relatively little cytoplasm. Nerve fibers stained positively for striatal enriched protein tyrosine phosphatase were also present in the globus pallidus and the substantia nigra, and the nigral labeling on the ipsilateral side almost disappeared subsequent to cerebral hemitransection, suggesting these immunolabeled structures to be striatal projections. Double-immunofluorescence analysis demonstrated separate populations of striatal enriched protein tyrosine phosphatase-positive cells and neurons stained for parvalbumin. Also, ultrastructural study showed that the striatal enriched protein tyrosine phosphatase-positive neurons (n = 50) possessed no nuclear indentations or intranuclear inclusions. Thus, most striatal striatal enriched protein tyrosine phosphatase-positive neurons were thought to be of the medium-sized spinous type. At the light microscopic level, stained striatal neurons exhibited striatal enriched protein tyrosine phosphatase immunolabeling in their somata, dendrites and axonal processes, but not in their nuclei. Electron microscopic observation showed strong striatal enriched protein tyrosine phosphatase-immunoreactivity on the inner surface of the plasmalemma, on the outer surfaces of mitochondria and on microtubules, particularly of dendrites. A heavy deposit of immunoreaction product was also present on postsynaptic densities in labeled dendrites, while a light deposit was seen on the synaptic vesicles of nerve terminals. The characteristic distribution profile of striatal enriched protein tyrosine phosphatase suggested that the enzyme may play a role in a variety of functional properties of striatal neurons, especially in postsynaptic signaling processes and in regulation of microtubular functions. On the basis of the present findings, we propose the following conclusions: (i) a protein tyrosine phosphorylation system regulated by striatal enriched protein tyrosine phosphatase is involved in certain specialized cellular processes (e.g. signal transduction cascades) of medium-sized spinous neurons distinct from those of other neuronal subsets in the striatum; (ii) a striatal medium spiny neuron is characterized by its expression of striatal enriched protein tyrosine phosphatase and, therefore, the enzyme is useful for detection of the distinct subset of striatal cells or for tracing their axonal projection fibers in the basal ganglia.

Animals↗
PubMed1995

Proliferating cell nuclear antigen may be superior to argyrophilic nucleolar organizer regions in predicting shortened survival of patients with non-small cell lung cancer.

We examined proliferating cell nuclear antigen (PCNA) in 102 patients with surgically treated non-small cell lung cancer (NSCLC). PCNA labelling index (LI) tended to be higher in tumours of higher stages than those of early stages, in squamous cell carcinomas than adenocarcinomas, or in poorly differentiated adenocarcinoma than in well-differentiated. A positive correlation was observed between the PCNA LI and argyrophilic nucleolar organizer regions (Ag-NOR) count which we previously examined (r = 0.31, P = 0.002). In survival analysis of 79 patients who died of lung cancer, only age, stage and PCNA LI were found to be significant prognostic factors on multivariate analysis among seven potential prognostic factors including sex, age, year of operation, histological type, stage, Ag-NOR count, and PCNA LI. We conclude that PCNA may be superior to Ag-NOR in predicting shortened survival of patients with non-small cell lung cancer. PCNA staining can be performed with ease and it may be applied in a clinical laboratory on a routine basis to help predict prognosis of NSCLC.

Adult↗
PubMed1995

p53 nuclear immunostaining and gene mutations in non-small-cell lung cancer and their effects on patient survival.

BACKGROUND: p53 gene mutations are known to occur in about half of all non-small-cell lung cancer (NSCLC) cases. Mutations of the p53 gene usually but not always lead to an increased half life of the p53 protein, and result in a nuclear accumulation of protein which can be detected by immunohistochemistry (IHC). Controversy still exists as to whether the presence of an aberration of the p53 gene or protein is a poor prognostic indicator in patients with NSCLC. PATIENTS AND METHODS: DNA samples and paraffin blocks were obtained from 129 patients of 143 consecutive patients who underwent a pulmonary resection during a 22-month period from July 1991 to April 1993. Mutations of the p53 gene occurring at exons 5-8 were detected by a polymerase chain reaction (PCR)/single strand conformation polymorphism (SSCP) assay, while the nuclear accumulation of the p53 protein was detected by immunohistochemistry. RESULTS: Of the patients studied, 35% had mutations and 54% showed overexpression, when we defined a positive case as being one in which more than 10% of the tumor cell nuclei were stained. There was a 59.5% concordance between the p53 gene mutations and p53 immunopositivity. p53 immunopositivity in adenocarcinoma and any p53 abnormality (i.e. p53 immunopositivity and/or mutation) in adenocarcinoma were a poor prognostic indicator. However, Cox's proportional hazards model indicated that the stage was the only significant prognostic factor. CONCLUSIONS: p53 immunopositivity and mutations of the p53 gene are frequently seen in NSCLC. They are considered to be mutually related but may sometimes represent a different aspect of p53 abnormality. p53 alteration may be a poor prognostic indicator only in a subset of patients with NSCLC, especially for adenocarcinoma.

Carcinoma, Non-Small-Cell Lung↗
PubMed1995

Inhibition of colon cancer cell proliferation by antisense oligonucleotides targeting the messenger RNA of the Ki-ras gene.

Point mutations that activate the Ki-ras proto-oncogene are present in approximately 50% of human colorectal tumors and the activated Ki-ras gene is considered to play an important role in colorectal cancer cell proliferation. Five different colon cancer cell lines and two kinds of control cell lines were treated with antisense oligonucleotides complementary to the messenger RNA of Ki-ras. Treatment with antisense oligonucleotides at concentrations between 10 and 40 microM significantly and dose-dependently inhibited cell growth, colony formation and Ki-ras protein production of the colon cancer cells with activated Ki-ras, but did not affect the normal cells and colon cancer cells without Ki-ras mutation. These results show that use of synthetic oligonucleotides is an effective way of producing antisense-mediated changes in the behavior of human colon cancer cells with an activated Ki-ras gene.

Antineoplastic Agents↗
PubMed1995

N-ras mutation of thyroid tumor with special reference to the follicular type.

Using the method of polymerase chain reaction-single strand conformation polymorphism, the point mutations of the ras oncogenes in a total of 33 thyroid tissues, including 12 follicular adenomas, 6 follicular carcinomas, 11 papillary carcinomas, and 4 undifferentiated carcinomas, were examined. The frequency of the mutation was 3% (1/33) in codon 12, 13 of Ki-ras and 18% (6/33) in codon 61 of N-ras, including 17% (2/12) in follicular adenoma, 50% (3/6) in follicular carcinoma, 0% (0/11) in papillary carcinoma and 25% (1/4) in undifferentiated carcinoma. In follicular adenoma, positivity was observed in microfollicular or trabecular subtypes. Furthermore, the mutation of ras, was examined in histologically different parts, coexisting in the same tumor in a total of four cases. Both the undifferentiated carcinoma and coexisting follicular adenoma, and both the microfollicular adenoma and trabecular nodule growing in the tumor, had the same N-ras (61) mutation. Direct sequencing analysis showed that all mutations were CAA (Gln) to CGA (Arg) transition of codon 61, except for CAA to AAA transversion in one case of follicular carcinoma. A similar genetic abnormality of N-ras genes at codon 61 between follicular adenoma and follicular carcinoma suggests that the mutation of N-ras at codon 61 might play a part in oncogenesis in follicular tumors.

Adenocarcinoma, Follicular↗
PubMed1995

Structure determination of biliary metabolites of schizandrin in rat and dog.

After oral administration of schizandrin (1) to rat, the bile was collected and treated with beta-glucuronidase and arylsulfatase. Eleven metabolites, SZ-M0 (3), SZ-M1 (4), SZ-M2 (5), SZ-M3 (6), SZ-M4 (7), SZ-M5 (8), SZ-M6 (9), SZ-M7 (10), SZ-M8 (11), SZ-M9 (12) and SZ-M10 (13) were isolated from the bile treated with the enzymes. The bile after oral administration of 1 to dog was collected and treated with enzymes in the same way, and eight metabolites, 3-8, 10 and SZ-MD2 (14) were isolated from the bile treated with enzymes. The structures of these metabolites were determined on the basis of chemical and spectral studies. The major metabolite in the bile of rat was 7 and the major metabolites in the bile of dog were 7 and 14.

Animals↗
PubMed1995

Serum level and tissue expression of c-erbB-2 protein in lung adenocarcinoma.

Serum levels of c-erbB-2 protein were measured by an enzyme immunoassay in 64 patients with lung adenocarcinoma. Immunohistochemical staining was performed in 40 of these tumors. The mean serum concentration was 16.5 +/- 8.5 U/mL (range: 3.4 to 49.0) in patients with lung adenocarcinoma, whereas it was 14.0 +/- 3.7 U/mL (range: 6.9 to 20.9) in 15 controls (1 U/mL = 0.61 ng/mL). Elevated concentrations (> or = 22.0 U/mL, control mean + 2 SD) were observed in 17/64 lung adenocarcinoma patients (26.6%), as compared with none of the control subjects (p < 0.05). Patients with stage IIIB or T4 disease had increased serum levels. The serum concentration was decreased significantly by surgical tumor ablation. Tissue overexpression was obtained in 17/40 cases (42.5%), and serum levels in patients with tissue overexpression were higher than in patients without overexpression. Serum c-erbB-2 protein may be a useful indicator of tumor burden in patients with lung adenocarcinoma.

Adenocarcinoma↗
PubMed1995

Pneumocystis carinii pneumonia during treatment for recurrent breast cancer: a case report.

We describe a case of Pneumocystis carinii pneumonia (PCP) in a woman with recurrent breast cancer without human immunodeficiency virus (HIV) infection. The PCP was associated with severe lymphocytopenia due to treatment with anticancer agents in combination with granulocyte colony-stimulating factor (G-CSF). Despite the severe lymphocytopenia, the total leucocyte count never fell below 3000/mm3 during the treatment. It was difficult to determine whether the patient's respiratory failure was caused by severe infectious pneumonia, hypersensitivity pneumonia or pneumonitis carcinomatosis. She was treated with steroid for suspected drug-induced hypersensitivity pneumonia. However, as her condition did not improve, PCP was suspected, and sulfamethoxazole-trimethoprim was administered. At the same time, anticancer drugs were administered to half the progression of the cancer, since lymphangitis carcinomatosa was also suspected. The severe respiratory failure did not improve, and the patient died on day 23 after admission. At autopsy, the cause of death was confirmed to respiratory failure due to PCP.

Adult↗
PubMed1995

[Aortic valve replacement for rheumatoid aortic valve regurgitation].

Valve replacement for aortic regurgitation in patient with rheumatoid arthritis was rare in Japan. We report a successful case in which aortic regurgitation necessitated aortic valve replacement. A 62-year-old woman was admitted for shortness of breath, chest pain and progressive edema. She had been treated for rheumatoid arthritis for more than ten years using steroids. The aortic valve was successfully replaced by a prosthetic mechanical valve. The histopathological examination of the excised aortic valve demonstrated rheumatic nodules in the right- and non-coronary cusp. It was supported that these changes caused shrinkage of cusp and resulted in aortic regurgitation. This patient was discharged on the 20th postoperative day. There was no evidence of detachment of the prosthetic valve.

Anti-Bacterial Agents↗
PubMed1995

[Pneumocystis carinii pneumonia associated with low dose methotrexate treatment for malignant rheumatoid arthritis].

Low dose pulse methotrexate (MTX) has become a widely used therapy for rheumatoid arthritis (RA) because of its good response rate profile. With the increased use of MTX, reports of opportunistic infections associated with MTX therapy have appeared. Fourteen cases of pneumocystis carinii (PC) pneumonia in patients receiving low dose MTX have been previously reported. Yet, no case of PC pneumonia associated with low dose MTX has so far been reported in Japan. We report the first case in Japan of PC pneumonia occurring in a patient with rheumatoid vasculitis who was receiving low dose MTX. A 70-year old woman with 13 year history of RA presented with 3-day history of rapidly aggravating dyspnea, dry cough and fever. She had been receiving MTX 7.5 mg/week for 2.5 months because of her vasculitis symptoms. She had also been receiving prednisolone 7.5 mg/day which had been successfully tapered from an initial dose of 15 mg/day. At the time of her presentation with respiratory symptoms, all of her vasculitis symptoms had been alleviated. A chest radiograph revealed diffuse interstitial shadowing bilaterally and bilateral hilar and right lower lung field infiltrates. Her arterial blood gas showed severe hypoxemia (PaO2 27.7 torr). Polymerase chain reaction assay of bronchoalveolar lavage fluid showed PC. Although the patient required ventilatory support for 9 days, she was successfully treated with trimethoprime-sulphamethoxazole and methylprednisolone pulse therapy. Eight months later, the patient was well with no evidence of vasculitis or respiratory symptoms.

Aged↗
PubMed1995

[Sleep apnea syndrome in rheumatoid arthritis (RA) patients complicated with cervical and temporomandibular lesions].

All-night polysomnographic studies were performed on ten patients (all female) with rheumatoid arthritis complicated with temporomandibular joint destruction and cervical lesions. The mean age of these subjects was 67.5 yrs, ranging from 48-81 yr. They all had some morphologic abnormalities of cervical spines and/or temporomandibular joints. Sleep study revealed that all of them had sleep apnea; five of them were of obstructive type (obstructive group) while the remaining showed central type of sleep apnea (central group) predominantly. There were no statistically significant differences of the levels of apnea index, mean-nadir SO2 and the lowest SO2 between the obstructive group and the central group. No detectable differences of cephalographic measurements and MRI findings existed between the two groups either. In one patient, nasal-CPAP converted central apnea to normal breathing dramatically. Our observations indicate that the cause of central apnea in RA patients with temporomandibular lesions is collapse of upper airway, inducing inhibitory inputs from the mechanoreceptors in that region.

Aged↗
PubMed1995

Fibromatosis of the breast: a case report.

Fibromatosis of the female breast is rare. We dealt with a recurrent case of fibromatosis four months after a wide excision of the tumor. It was difficult to differentiate the tumor from carcinoma and only a pathological examination could lead to the final diagnosis. Ultrasonographic findings are so characteristic that we would like to emphasize the usefulness of ultrasonography not only in distinguishing between recurrence and operative scar but also in defining the diagnosis as fibromatosis of the breast.

Adult↗