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T Oyama

Publications and source records attributed to T Oyama.

At least 109 records · Page 6Linked to original sources
PubMed1998

In situ hybridization with biotinylated tyramide amplification: detection of human papillomavirus DNA in cervical neoplastic lesions.

A novel peroxidase-mediated amplification system, which is based on the deposition of biotinylated tyramide (BT) molecules, was recently described for immunohistochemistry and in situ hybridization (ISH). We report here a highly sensitive ISH system combined with a microwave prehybridization treatment and BT enhancement after hybridization. Our ISH with BT amplification can detect human papillomavirus (HPV) 16 DNA signals in the fixed SiHa cell, suggesting the ability to detect single or few copies of HPV DNA. To confirm its diagnostic usefulness, we used our ISH with BT amplification to detect HPV 16 DNA in 81 cases of cervical neoplastic lesions, which had been used for routine pathologic diagnosis. Of 81 tumors, 47 (58%) showed HPV 16 DNA, of which 29 and 18 were cervical intraepithelial neoplasia (CINs) and invasive cancers, respectively. In almost all of the invasive cancers positive for HPV 16 DNA, ISH revealed a basic dot signal pattern in the nuclei, suggesting that HPV DNA integrated into tumor cell DNA. On the other hand, low-grade CINs displayed a diffuse, mainly episomal, signal pattern, which decreased in frequency with increased grade of CIN. Our ISH with BT amplification is highly sensitive and can be used to detect various genes and their expressions.

DNA, Viral↗
PubMed1998

[Analysis for predicting the prognostic factors of gastrointestinal tract leiomyosarcoma using MIB-1 and DNA flow cytometry].

PURPOSE: The present study was undertaken to investigate the possibility of determining a prognosis for gastrointestinal tract leiomyosarcoma with the use of DNA analysis and MIB-1 staining. SUBJECTS AND METHODS: Malignant tumors originating in smooth muscle of the gastrointestinal tract, surgically excised from 23 lesions in 17 patients (stomach; 8 cases, 12 lesions; small intestine: 6 cases, 8 lesions; colon: 3 cases, 3 lesions) and embedded in paraffin, were examined. DNA was analyzed using flow cytometry to produce a DNA histogram, and aneuploidy and diploidy were found. MIB-1 staining was done in conformity with the ABC method. RESULTS: 1. An investigation of prognoses using the Kaplan-Meier method revealed a tendency for more favorable prognoses in patients determined to be aneuploid through DNA analysis. However, this was not significantly better than those exhibiting diploidy. 2. All patients who died had a MIB-1 staining positivity rate of over 10%, while all patients who had no recurrence within one year or survived had a MIB-1 staining positivity of less than 10%. 3. No consistent trends were observed between MIB-1 positivity rate and DNA analysis, MIB-1 positivity rate and size of tumor, or DNA analysis and size of tumor. 4. The MIB-1 positivity rate of patients with remote metastases was significantly greater than that of patients with no remote metastases. CONCLUSION: From the fact that patients with MIB-1 positivity rates of greater than 10% had a poor prognosis, while those with rates of less than 10% had a favorable prognosis, we conclude that a MIB-1 positivity rate of 10% is an important value in determining the prognosis of patients with gastrointestinal tract leiomyosarcomas.

Adult↗
PubMed1998

[Genetic testing for ret mutation for early diagnosis and treatment in familial medullary thyroid carcinoma: a case report].

A 13-year-old girl and her older sister were referred to our hospital because her father and another older sister and been suffering from medullary thyroid carcinoma (MTC). Physical examinations revealed no thyroid mass. Ultrasonography (US) detected a small hypoechoic lesion in the right thyroid lobe, 3 mm in size. The serum calcitonin level was slightly elevated for their age. One and half year later, US finding showed a slightly larger mass, 7 mm in size, which was not palpable. Genetic testing for ret protooncogene mutation revealed a point mutation at codon 634 (Cys-->Arg) in exon 11. Surgical treatment was recommended, however, the patient wanted to receive it only after the admission to senior high school. Her sister had no mutation in ret protooncogene. The patient underwent total thyroidectomy with modified neck dissection at 16 years of age. At that time, a new mass emerged in the left thyroid lobe and the serum calcitonin level increased to 171 pg/ml. MTC was found in each lobe with positive staining of CEA and carcitonin. No lymph node metasis was found. Her postoperative course was uneventful. Genetic testing for ret mutation is effective for early diagnosis and treatment of patient with FMTC, and is recommended as standard management for hereditary MTC in affected families.

Adolescent↗
PubMed1997

The Arabidopsis HY5 gene encodes a bZIP protein that regulates stimulus-induced development of root and hypocotyl.

Plant developmental processes are controlled by both endogenous programs and environmental stimuli. As a photomorphogenetic mutant, hy5 of Arabidopsis has been isolated and characterized. Our detailed characterization has revealed that the mutant is deficient in a variety of stimulus responses, including gravitropic response and waving growth of roots, as well as light-dependent hypocotyl elongation. In the roots and hypocotyl, the hy5 mutation also affects greening and specific cell proliferation such as lateral root formation and secondary thickening. Those phenotypes indicate that the HY5 gene is responsible for the regulation of fundamental developmental processes of the plant cell: cell elongation, cell proliferation, and chloroplast development. Molecular cloning of the HY5 gene using a T-DNA-tagged mutant has revealed that the gene encodes a protein with a bZIP motif, one of the motifs found in transcriptional regulators. Nuclear localization of the HY5 protein strongly suggests that the HY5 gene modulates the signal transduction pathways under the HY5-related development by controlling expression of genes downstream of these pathways.

Amino Acid Sequence↗
PubMed1997

Detection of interstitial pneumonitis in patients with rheumatoid arthritis by measuring circulating levels of KL-6, a human MUC1 mucin.

In rheumatoid arthritis (RA), interstitial-pneumonitis is one of the major extraarticular complications that worsens a patient's prognosis. KL-6, a human MUC1 mucin, has been reported to be a sensitive serum marker for activity of interstitial pneumonitis. We investigated the clinical significance of serum KL-6 level in patients with RA. Serum levels of KL-6 and RA-associated inflammatory markers were evaluated in 177 RA patients. The diagnosis of active interstitial pneumonitis was made by clinical symptoms, pulmonary function tests, chest X-ray film, and high resolution CT. Serum KL-6 was increased in 8 of 9 (88.9%) RA patients with active interstitial pneumonitis but in only 1 of 168 (0.6%) RA patients without active interstitial pneumonitis. No significant correlation was found between KL-6 level and conventional clinical parameters. In RA, abnormal elevation of serum KL-6 strongly indicates the complication of active interstitial pneumonitis.

Adult↗
PubMed1997

Micrometastatic tumor cells in the bone marrow of patients with non-small cell lung cancer.

BACKGROUND: This study was designed to evaluate the incidence and clinical implications of detection of micrometastatic cancer cells in bone marrow aspirates of patients with operable non-small cell lung cancer. The relationship between micrometastatic cells and p53 overexpression in the primary tumor was also assessed. METHODS: Thirty-nine patients with stages I through III non-small cell lung cancer who underwent curative resection were entered into this study. Immunohistochemistry with monoclonal antibody to cytokeratin 18 was used to detect tumor cells in bone marrow. Immunostaining of p53 protein in the corresponding primary tumors was also done. RESULTS: Cytokeratin 18-positive cells were detected in 15 (39%) of the 39 patients. Overexpression of p53 was associated with positivity of the tumor cells in the bone marrow at borderline significance (14/29 versus 1/10; p = 0.0574). The patients with cytokeratin 18-positive cells in bone marrow demonstrated a significantly earlier recurrence than those without such cells (p = 0.0083, log-rank test). CONCLUSIONS: Micrometastatic cancer cells were frequently present in bone marrow of patients with operable non-small cell lung cancer and may be a significant predictor of early recurrence. Further evaluation of this method may be useful in identifying patients with non-small cell lung cancer who are most likely to benefit from adjuvant chemotherapy.

Aged↗
PubMed1997

Immunohistochemical assessment of proliferative activity in mammary adenomyoepithelioma.

AIMS: Two cases of adenomyoepithelioma of the breast were examined by immunohistochemistry to evaluate proliferative activity of epithelial and myoepithelial components. METHODS AND RESULTS: The tumours showed a bicellular pattern of gland-forming epithelial cells and proliferative myoepithelial cells with clear cytoplasm. They showed foci of monotonous growth of myoepithelial cells devoid of glands with low mitotic rate (1-2/10 high-power fields) and mild cytological atypia. Immunohistochemically, the glandular cells were positive for epithelial membrane antigen, cytokeratin (KL-1 and CAM5.2) and carcinoembryonic antigen, whereas tumour cells with clear cytoplasm were reactive with muscle-specific actin (MSA), alpha smooth muscle actin, vimentin, and S100 protein but negative for desmin. Proliferative activities assessed by MIB-1 (Ki-67)/MSA positive cell index were greater in myoepithelial cells in both cases (19.2% and 17.7%) as compared to those in epithelial cells (MIB-1/CAM5.2 index: 10.2% and 9.5%). CONCLUSIONS: These results might account for the previous findings that myoepithelial components predominate over the epithelial ones in an advanced stage of this tumour as well as in recurrent or metastatic lesions.

Aged↗
PubMed1997

Spindle cell carcinoma of the breast.

Spindle cell carcinoma is a rare breast tumor. We present herein three cases of spindle cell carcinoma of the breast and review its characteristics from the literature. Spindle cell carcinoma frequently forms a large and well-circumscribed tumor with gross cyst formation. Histologically, its dominant component is of sheets of spindle shaped cells, and it includes such contiguous carcinoma components as squamous differentiation or invasive ductal carcinoma. Estrogen receptor expression and lymph node metastasis tend to be low. Despite the sarcomatous features, spindle cells are likely to be derived from epithelial cells of mammary glands. Immunohistochemical and ultrastructural examination demonstrated the expression of keratin and the desmosome-like junctional structure in the spindle cell components. Relatively favorable prognosis is expected in spindle cell carcinoma of the breast compared to common breast carcinoma.

Aged↗
PubMed1997

Why is cyclooxygenase-2 expressed in neuroendocrine cells of the human alimentary tract?

During immunohistochemical studies of cyclooxygenase-2 (COX-2) on human colon cancers, many strong COX-2-immunoreactive cells scattered in the bottom of the crypt of normal colon mucosa were unexpectedly noticed. COX-2-immunoreactive cells were morphologically very similar to neuroendocrine cells and were confirmed immunohistochemically to be positive for chromogranin A or serotonin. Moreover, COX-2-immunoreactive neuroendocrine cells were observed not only in the large intestine, but also in the stomach, duodenum and small intestine. The role of COX-2 expression in neuroendocrine cells of the human alimentary tract was speculated.

Blotting, Western↗
PubMed1997

Intractable diarrhoea associated with secondary amyloidosis in rheumatoid arthritis.

OBJECTIVE: To examine the clinical characteristics of intractable diarrhoea associated with secondary amyloidosis in rheumatoid arthritis (RA). METHODS: Of 179 RA patients with biopsy confirmed secondary amyloidosis, 24 cases (23 women and one man) with intractable diarrhoea lasting for more than one month were retrospectively evaluated. RESULTS: The mean (SD) duration of diarrhoea was 87 (64) days. Prodromal symptoms of gastrointestinal dysfunction (n = 21) and impaired peristalsis (n = 16) were observed. Laboratory data showed hypoproteinaemia (4.7 (0.85) g/dl) caused by malabsorption or protein loss and high values of C reactive protein (17.0 (9.3) mg/dl). Recurrence of intractable diarrhoea (n = 4) and transition from intractable diarrhoea to other gastrointestinal problems of amyloidosis (ischaemic colitis (n = 2) and intestinal pseudo-obstruction (n = 4)) were observed. In 19 patients (25 episodes) the duration of intravenous hyperalimentation at remission (18 episodes) was 68 (52) days. Corticosteroid pulse therapy was administered to 10 patients (11 times) and the time elapsed from the end of corticosteroid pulse therapy to the end of diarrhoea was 18 (14) days. One and five year survival rates after the onset of intractable diarrhoea were 73.4% and 38.9%. Seven of 13 patients (54%) had died as a result of infectious diseases. CONCLUSION: Intractable diarrhoea associated with secondary amyloidosis in RA is a serious clinical entity and the prognosis is poor. Although it is assumed that intravenous hyperalimentation treatment and corticosteroid pulse therapy are favourable regimens for intractable diarrhoea, the patients should be monitored for possible infectious complications.

Adult↗
PubMed1997

Analgesic effect of a herbal medicine for treatment of primary dysmenorrhea--a double-blind study.

We evaluated the analgesic effect of Toki-shakuyaku-san (TSS) in women who had a combination of "deficiency," of "Yin," "cold," and "stagnated blood" syndromes, and were suffering from dysmenorrhea. A diagnostic scoring system was used for determination of these conditions. We treated patients with either TSS or placebo during 2 menstrual cycles with a double-blind technique, and we followed them for 2 additional cycles. A significant alleviation of dysmenorrhea was observed in patients treated with TSS as compared to those treated with placebo. Our results suggest that TSS is effective for treatment of dysmenorrhea in patients with the above-mentioned conditions.

Adolescent↗
PubMed1997

Effectiveness of retrograde perfusion of the cerebral vein for attenuating neuronal injury after transient ischemia following reperfusion in the rat brain.

The effect of retrograde perfusion of the cerebral vein (RPCV) with antioxidant LY231617 on neuronal injury after transient ischemia in rat brain was examined. Transient ischemia was caused by left middle cerebral artery (MCA) occlusion and reperfusion. Rats were assigned to three groups: Group A (n = 6), MCA occlusion only; Group B (n = 8), RPCV with saline (flow rate 4.95 ml/hr) into the left inferior cerebral vein; and Group C (n = 6), RPCV with LY231617 (20 mg/kg/hr, flow rate 4.95 ml/hr). RPCV in Groups B and C was performed simultaneously with occlusion. Both occlusion and RPCV were performed for 30 minutes in awake animals. Seven days later, all rats were investigated for rotational behavior elicited by apomorphine (1.0 mg/kg), and then immunohistochemical analysis of brain specimens was carried out using calcineurin as a neuronal marker in the striatum to detect the ischemic damaged area. The number of turns to the left (lesioned side) in both Groups B (42 +/- 12) and C (46 +/- 14) was significantly lower (p < 0.01) than in Group A (222 +/- 45), but there was no significant difference between Groups B and C. The percentage ischemic damaged area in both Groups B (17.9 +/- 6.2%) and C (1.6 +/- 1.0%) was significantly less (p < 0.01) in Group A (51.1 +/- 2.1%). RPCV with and without LY231617 during occlusion was effective for attenuating reperfusion injury.

Animals↗
PubMed1997

[Quantitative evaluation of response at acetazolamide test using 99mTc-ECD SPECT; a trial of production of the response map].

In the method by Matsuda and Takeuchi et al. for easy regional cerebral blood flow (rCBF) measurements at pre- and post-acetazolamide tests using 99mTc-ECD, a study was done for producing the increase rate of rCBF as a response map after acetazolamide administration. To prepare the response map calculated from the arithmetic operation of [(rCBF image at administration--rCBF image at rest)/rCBF image at rest x 100], the images were preprocessed by combination of matrix size conversion and smoothing techniques and then areas outside the brain were masked to remove amplified noises. The response map seemed helpful for visual evaluation of the response after acetazolamide administration, and also for understanding the disease conditions and clinical courses.

Acetazolamide↗
PubMed1996

Postoperative complications after pneumonectomy for treatment of lung cancer: multivariate analysis.

The charts of 62 patients with primary lung cancer who underwent a pneumonectomy at our department from 1979 through 1992 were reviewed for the evaluation of postoperative morbidity and mortality. The 30-day mortality was 3/62 or 4.8%. Postoperative complication occurred in 37 of 62 patients (60%). The most common complication was a supraventricular tachyarrythmia. A major complication, which was defined as one necessitating re-thoracotomy or one which caused death, occurred in 19 patients (31%). We analyzed 43 perioperative variables for their predictive value of postoperative morbidity and mortality. Univariate analysis indicated that an elevated serum LDH, low predicted forced vital capacity, low predicted forced expiratory volume in 1 sec (FEV1) were significantly associated with the occurrence of a major complication. A multivariate logistic regression model indicated that a high LDH level, a low predicted FEV1 and no extubation following surgery were associated independently with a postoperative major complication. Since only the complete removal of a tumor offers a chance for cure for the treatment of non-small cell lung cancer, it is sometimes necessary to perform a pneumonectomy for these high-risk patients. Patients identified as being at high risk of a major complication should be candidates for intensive preoperative evaluation and perioperative care.

Adult↗
PubMed1996

Case of myoepithelioma originating from the palate: collagenogenesis in myoepithelial tumor cells.

We report a case of myoepithelioma of the palate in a 53-yr-old man. Myoepithelioma cells consisting of both plasmacytoid type and spindle type were obtained. A reticular pattern composed of a mosaic arrangement of hyaline-like abundant cytoplasm, and scant matrix and considerable fiber formation were characteristic features of the plasmacytoid type; granular cytoplasm and a snake-like shape were characteristic features of the spindle type. These are important points in differentiating this tumor from cellular type pleomorphic adenoma. The present study shows that tumorous myoepithelial cells can synthesize and secrete extracellular components such as proteoglycans, basal lamina, collagen fibers, and elastic fibers.

Adenoma, Pleomorphic↗
PubMed1996

Cytochrome oxidase activity during acute focal ischaemia in rat brain. A pathophysiology of acute focal ischaemia: Part 2.

An enzyme-histochemical technique was used to examine the changes in cytochrome oxidase activity during acute focal ischaemia in the rat. In the somatosensory cortex, the enzyme activity began to increase significantly (p < 0.01) 1 hour after middle cerebral artery occlusion (MCAO) and continued to increase up to 3 hours, during which ischaemic cell damage was not detected. In the striatum, the enzyme activity increased significantly (p < 0.01) 1 hour after MCAO in the absence of morphological evidence of ischaemic cell damage; a peak activity was reached at 2 hours, and began to decline 3 hours after MCAO when moderate ischaemic change was detected. In both cortical and subcortical areas, the enzyme activity tended to decrease from 4 hours after MCAO, and was reduced to a level similar to or below that of the non-ischaemic hemisphere 5 hours after MCAO, when severe ischaemic damage was demonstrated. The relation of this transient increase of cytochrome oxidase activity in the early stage of acute ischaemia and the hypermetabolism of neuronal cells during ischaemic insult was discussed.

Animals↗