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Biomedical subjects

T Okayasu

Publications and source records attributed to T Okayasu.

At least 19 recordsLinked to original sources
PubMed2005

Epithelial and stromal genetic instability contributes to genesis of colorectal adenomas.

BACKGROUND: Previously, we indicated that stromal genetic instability might contribute to tumorigenesis of both sporadic and ulcerative colitis associated colorectal adenocarcinomas. Considering the established adenoma-adenocarcinoma sequence, in this study we analysed genetic instability in colorectal adenoma cells and surrounding stroma. METHODS: In 164 colorectal tumours (34 hyperplastic polyps, 38 tubular adenomas with low grade dysplasia (TA-L), 51 tubular adenomas with high grade dysplasia (TA-H), and 41 invasive carcinomas), epithelial and stromal genetic instability with National Cancer Institute standard microsatellite markers and chromosome 17 (Chr17) markers, were analysed by a combination of laser capture microdissection and GeneScan approaches. RESULTS: While frequencies of both loss of heterozygosity (LOH) and microsatellite instability (MSI) were extremely low in hyperplastic polyps, LOH in tubular adenomas was detected in both epithelial (TA-L 13.2%, TA-H 27.5%) and stromal (5.3% and 5.9%, respectively) elements, along with MSI (5.3% and 13.7%, and 5.3 and 5.9%, respectively). Frequencies of epithelial alterations were higher in TA-H than in TA-L, and greatest in the carcinoma group. On the other hand, frequencies of stromal LOH or MSI were almost constant (5.3% approximately 17.1%, 5.3% approximately 17.1%, respectively) in adenomas and invasive carcinomas. In addition, p53 was found to be significantly overexpressed in a greater proportion of TA-L with LOH than in those without genetic instability. CONCLUSION: The results indicate the presence of genetic alterations in stroma from an early stage of carcinogenesis, accompanied by stepwise increasing genetic instability of epithelia with progression to cancer. Thus microenvironmental changes due to genetic alteration in Chr17 markers in stromal cells may play an important role in colon adenoma and adenocarcinoma development.

Adenocarcinoma↗
PubMed2001

Conservation of the basic pattern of cellular amino acid composition of archaeobacteria during biological evolution and the putative amino acid composition of primitive life forms.

Previous studies showed that the cellular amino acid composition obtained by amino acid analysis of whole cells, differs such as eubacteria, protozoa, fungi and mammalian cells. These results suggest that the difference in the cellular amino acid composition reflects biological changes as the result of evolution. However, the basic pattern of cellular amino acid composition was relatively constant in all organisms examined. In the present study, we examined archaeobacteria, because they are considered important in understanding the relationship between biological evolution and cellular amino acid composition. The cellular amino acid compositions of Archaeoglobus fulgidus, Pyrococcus horikoshii, Methanobacterium thermoautotrophicum and Methanococcus jannaschii differed slightly from each other, but were similar to those determined from codon usage data, based on the complete genomes. Thus, the cellular amino acid composition reflects biological evolution. We suggest that primitive forms of life appearing on earth at the end of prebiotic evolution had a similar-cellular amino acid composition.

Amino Acids↗
PubMed2000

Conservation of the basic pattern of cellular amino acid composition during biological evolution in plants.

The cellular amino acid composition of plant cells was analyzed. The callus of carrot (Daucus carota), leaves of Torenia fournieri and protocomb-like body of Cymbidium, s.p. were examined as examples of plant cells. The cellular amino acid compositions differed in the plant cells, but their basic patterns were quite similar. It is concluded that the basic pattern of the cellular amino acid composition is conserved in all terrestrial organisms, including plants.

Amino Acids↗
PubMed2000

[Surgery for intrathoracic recurrence of non-small cell lung cancer].

In this study, we defined a solitary lung nodle in the same histology which could be traced its' origin from carcinoma in situ or was found over than two years' follow up as a second primary lung cancer. These cases were excluded. Eighteen cases underwent second surgery for intrathoracic recurrence. Fourteen cases were male and four cases were female. Their ages ranged from 23 to 75 (average 59.6) years. The histology were adenocarcinoma in 9 cases, squamouscarcinoma in 7, adenosquamous carcinoma in 1, large cell carcinoma in 1. The initial surgical procedures were lobectomy in 17, partial resection in 1. The initial stage were I in 13, II in 2, IIIA in 1. Pulmonary recurrence were found in 10, bronchial stump recurrence were found in 4, pulmonary hilus lymph node recurrence were found in 2, mediastinal lymph node recurrence were found in 2, pulmonary stump recurrence was found in 1. The second surgical procedures were completion pneumonectomy in 7, completion lobectomy in 1, lobectomy with segmentectomy in 1, segmentectomy or partial resection in 7, mediastinal dissection in 2. The overall 5-year survival rate of the patients with recurrence after reoperation was 31.8%. An aggressive surgical approach for recurrent lung cancer should be recommended.

Adult↗
PubMed1998

[Clinical evaluation of Dumon stent for tracheobronchial stenosis due to advanced esophageal carcinoma].

We inserted Dumon stent to 13 patients with tracheobronchial stenosis due to advanced or recurrent esophageal carcinoma. Severe dyspnea was improved in 11 patients except for 2 patients with bilateral recurrent nerve palsy. 3 cases who had radiation therapy or chemotherapy lived over 150 days. We inserted esophageal stent in 4 cases. 2 patients died due to hemoptysis after 156 days and 35 days. We conclude that Dumon stent is one of the useful treatments in order to improve quality of life and prognosis of advanced or recurrent esophageal carcinoma.

Aged↗
PubMed1998

Acetabular dysplasia and hip osteoarthritis in Britain and Japan.

OBJECTIVE: Geographic differences in the prevalence of hip osteoarthritis (OA) have been ascribed to differences in the frequency of acetabular dysplasia among different ethnic groups. However, there are few data on the shape of the acetabulum in various populations around the world. We examined this issue in samples of pelvic radiographs from Britain and Japan. METHODS: Measurements were made on the pelvic radiographs of 1303 men and 195 women, aged 60-75 yr, who attended for i.v. urography in two British centres. These were compared with 99 men and 99 women aged 60-79 yr who were included in a population-based study in a rural community in Japan, and who agreed to undergo standardized pelvic radiography. Acetabular dysplasia was assessed by morphometric measurement of the centre-edge (CE) angle and acetabular depth. RESULTS: The mean CE angle among men was 36 degrees (95% CI 35-37 degrees ) in Britain and 31 degrees (95% CI 29-32 degrees ) in Japan; that in women was 37 degrees (95%, CI 36-38 degrees ) in Britain and 31 degrees (95% CI 29 33 degrees ) in Japan. The mean values of acetabular depth were also significantly (P < 0.001) lower in Japan than in Britain. However, the prevalence of hip OA was lower in Japan (0% in men, 2% in women) than in Britain ( 11% in men, 4.8 / in women). In a random effects model, there were negative relationships between measures of acetabular dysplasia and minimum joint space among individuals. CONCLUSIONS: We conclude that there are marked differences in pelvic morphometry between Britain and Japan. The acetabular dimensions of Japanese subjects are considerably shallower than those of their British counterparts of similar age and sex. Nevertheless, hip OA is more frequent in Britain than in Japan. Further studies are required on the risk factors for hip OA in Oriental populations, in order that the aetiology of this disorder can be better understood.

Acetabulum↗
PubMed1995

[Histological effect and prognosis after preoperative chemotherapy in esophageal cancer].

Preoperative chemotherapy for esophageal cancer was performed and the toxic effects, post-operative complications, histological effects and survival time were evaluated. Toxic effects and post-operative complications were rare. The histological effect was evaluated according to the Guidelines for Clinical and pathologic studies on carcinoma of the esophagus by the Japanese Society for Esophageal Disease. A histological effect of more than Grade II was seen from 25 to 42.1%. A significant difference was seen in the Kaplan-Meier survival curves between the response group and the no response group (p < 0.05). If we perform preoperative chemotherapy for esophageal cancer only to responsive cases determined by chemosensitivity tests, the prognosis of advanced esophageal cancer may be improved.

Adult↗
PubMed1995

[Clinical experiences with the insertion of Dumon-type endotracheal stent tube for the patients with tracheal stenosis due to advanced esophageal carcinoma].

To relieve tracheal stenosis due to esophageal carcinoma, we have inserted Dumon-type endotracheal stent tube to 2 patients with stenosis of the left main bronchus and a patient with tracheal stenosis. Severe dyspnea and stridor found in these patients was much improved in all three cases. After insertion of the stent tube to 2 patients with stenosis of the left main bronchus, radiation therapy with the dose of 65 Gy to main esophageal lesion was undergone, which resulted in the partial remission. These management allowed the patients to discharge. The last case with tracheal stenosis was due to recurrence of the esophageal carcinoma, which required additional insertion of the stent tube at the proximal site after initial insertion in a short period. We conclude that the quality of life and prognosis of patients with tracheal stenosis due to advanced esophageal carcinoma may be improved by the insertion of Dumon-type endotracheal stent tube.

Aged↗
PubMed1994

Inhibition of catabolic pathway of 5-fluorouracil by 3-cyano-2,6-dihydroxypyridine in human lung cancer tissues.

Our studies of the degradation and the phosphorylation of 5-fluorouracil (5-FU) in normal and tumor lung tissues from 10 cases of lung cancer have shown that the phosphorylation of 5-FU in the tumor tissues was about 2- to 3-fold higher than that in normal tissues, and that the degradation of 5-FU in tumor tissues was nearly 6-fold higher than that in normal tissues. BOF-A2 is an anti-neoplastic agent newly synthesized from 1-ethoxymethyl-5-FU and 3-cyano-2,6-dihydroxypyridine (CNDP). The inhibitory effect of CNDP on the degradation of 5-FU in the tumor tissues was potent (IC50 3.9 x 10(-9) M). Thus, BOF-A2 exerts its anti-neoplastic effect on tumors by potentiating the action of 5-FU through inhibition of 5-FU degradation by the CNDP moiety.

Adenocarcinoma↗
PubMed1994

[Clinical study on reoperation for recurrent pulmonary metastasis].

Ninety seven patients with metastatic lung tumors were treated surgically in our department. Second pulmonary resections were performed in 13 patients. They consists of 9 males and 4 females, their age ranged from 12 to 75 years old (average 54.4 years old). Tumors originate from sarcoma in 5 cases, laryngeal cancer, colorectal cancer, renal cell cancer in 2 cases respectively, oral cavity cancer and transitional cell cancer in 1 case respectively. No second pulmonary resection was performed in patients with metastatic lung tumors originating from lung cancer or breast cancer, because they metastatize not only lung but also general organs. No second pulmonary resection was required in patients with testicular tumor and choriocarcinoma, because chemotherapy take good effect on them.

Adult↗
PubMed1993

[Surgical analysis for lung cancer with scalene node metastasis].

In this study, we evaluated 15 surgically treated cases of lung cancer with scalene node metastasis. Eleven males and 4 females with ages ranging from 41 years to 78 years (average 59.1 years) were examined. Seven cases was in the right upper lobe, 3 in the left upper lobe, 2 in the right lower lobe, 2 in the left lower lobe, 1 in the middle lobe. Adenocarcinomas were found in 9 cases squamous cell carcinomas were in 4 cases and large cell carcinomas were in 2 cases. Two cases was in T 1, 7 in T 2, 2 in T 3, 4 in T 4. In all cases, lobectomy was performed. Five year survival rate was 14.3% as determined by the Kaplan-Meier method. Average survival period was 26.6 months. Three cases survived over 3 years including one case survived over 10 years.

Adenocarcinoma↗
PubMed1993

[Surgical analysis for metastatic lung tumor originating from renal cell carcinoma].

In this study, we evaluated 16 surgically treated cases of metastatic lung tumors originating from renal cell carcinoma. Ten males and 6 females with ages ranging from 31 years to 74 years (average 60.8 years) were examined. Five cases had solitary metastasis, 4 had ipsilateral multiple metastasis, and 7 had bilateral metastasis. The average number of lung metastatic legion was 3.3. Disease free intervals ranged from 0 to 120 months (average 22.6 months). Tumor doubling time calculated in only 8 cases, ranged from 36 to 510 days (average 126 days). In 8 cases, tumor doubling time could not be calculated because tumor growth was too slow. Partial resection or segmental resection was performed in 14 cases, 8 with ipsilateral and 6 with bilateral lung metastasis. Lobectomy was performed in only two cases. Five year survival rate was 43% as determined by the Kaplan-Meier method. We believe that such cases possessing a slow tumor growth rate have a better survival rate.

Adult↗
PubMed1992

Inherited copper toxicity in Long-Evans cinnamon rats exhibiting spontaneous hepatitis: a model of Wilson's disease.

The copper concentrations in organs of developing Long-Evans Cinnamon (LEC) rats (2 d to 13 mo) were measured to elucidate the pathogenesis of their hereditary hepatitis. Hepatic copper contents of LEC rats were significantly higher than those of control rats (26 to 92 times higher). The subcellular distribution of hepatic copper indicated that the nuclear and large granular fractions had been saturated and the cytosol fraction contained about 70% of all the hepatic copper in LEC rats. The serum concentrations of copper and ceruloplasmin were significantly lower than those of control rats from the 4th wk (10-12% and 5-19%, respectively). Copper contents in kidney of LEC rats did not exhibit an increase over those of control rats until 12 wk, but then increased to nearly 40 times higher during fulminant hepatic failure. Accumulation of copper was not detected in the brain or small intestines of LEC rats until 13 mo. The hepatic copper concentration, its subcellular distribution, and serum copper concentration of F1 rats (LEC x Long-Evans Agouti) exhibited the same levels as those of Long-Evans Agouti rats. In addition to their similarity concerning inheritance of autosomal recessive means and clinical course, we found causality relating copper accumulation to the pathogenesis of the disease. We propose that LEC rats will be the most promising animal model for the study of Wilson's disease.

Age Factors↗
PubMed1992

[The relationship between evaluation of school stressors and stress responses in junior high school students].

The purpose of this study is to develop a school stressor scale from the events experienced frequently by junior high school students in their daily school life, and to examine the relationship between school stressors and stress responses. In study I, factor analysis of data by 552 students revealed four main factors "teacher", "friend", "club activity", and "study", which were extracted from initial set of 72 items. In study II, factor analysis of 50 items, of which 39 items were extracted in study I, and 11 new items of free-description type, of data by 622 students, revealed that main stressors in junior high school were following six, "teacher", "friend", "club activity", "study", "rule", and "official activity". Furthermore, multiple regression analyses revealed that "friend" strikingly correlated with "depressive-anxious emotion" and "study" did with "cognition-thought of helplessness".

Adolescent↗
PubMed1992

[Surgical analysis of mediastinal lymphangioma--analysis of 7 cases].

Mediastinal lymphangioma is a very rare disease. In this study, we evaluated 7 surgically treated cases of mediastinal lymphangioma. Four males and 3 females with ages ranging from 5 months to 74 years (average 31.4 years) were examined. Four patients were asymptomatic but had abnormal shadows on their chest X-ray. Of the remaining patients, one had hoarseness and another had superior vena cava syndrome and both had dyspnea. The other patient was discovered because of cervical tumor. Multiple lymphangiomas were found in only 2 patients. One patient had 4 tumors and the other had 2 tumors in the mediastinum. Of all lymphangiomas, 2 were found in the superior mediastinum, 2 in the anterior mediastinum, 3 in the median mediastinum and 3 in the posterior mediastinum. All patients had cystic lymphangioma including 1 with capillary lymphangioma and 1 with cavernous lymphangioma. Median sternotomy was performed in 3 of the patients and posterolateral thoracotomy was performed in the remainder. The cervical tumor was removed by local incision. Complete resection of the lymphangiomas was performed and no recurrence was observed after surgery.

Adult↗
PubMed1991

The improved effects of specific active immunotherapy on a rat fibrosarcoma by antitumor drugs.

We have tried to find out if the combination of a xenogenized tumor cell vaccine and antitumor drugs is able to induce a synergistic increase in the antitumor therapeutic effect. The degree of increase in the LTD50 (50% lethal tumor dose) is expressed numerically, as a quantitative index designed to compare degrees of transplantation resistance to tumor cell challenge. A LTD50 was achieved by an intradermal (i.d.) immunization with xenogenized tumor cells when challenged with tumor cells implanted intraperitoneally 2 weeks after the immunization: this LTD50 value was 527,000 times higher than that of the non-immunized group. When we combined this type of immunization with appropriate doses of bleomycin (BLM) or cyclophosphamide (CY), which are able to augment antitumor immunity, the LTD50 was 723,000-1,190,000 times higher than that of the non-immunized group. This increase in the LTD50 is definitely higher than that achieved by a single immunization with irradiated tumor cells (x 33,000) and combined with either BLM (x 93,000) or CY (x 140,000). We also studied the therapeutic effect of a tumor cell vaccine combined with antitumor drugs BLM or CY in tumor-bearing rats. We observed a synergistic effect caused by BLM or CY after i.d. immunization with xenogenized tumor cells: this showed a significant increase when compared with the therapeutic effects obtained by chemotherapy alone (P less than 0.01). Nevertheless, there was no evidence that the above antitumor effects is superior to the effect achieved by irradiated tumor cells.

Animals↗
PubMed1991

[A case of bronchial artery aneurysm demonstrating a mass shadow on chest X-ray film].

A 66-year-old woman was admitted on May 13, 1989, because of an abnormal round shadow in the right hilum on chest X-ray film. Bronchoscopy revealed a stenosis of the right B8 caused by a bulging lesion. An aortogram showed a large meandering bronchial artery and a saccular aneurysm. The aneurysm was about 25 mm in diameter and associated with a bronchopulmonary anastomosis. It was surgically removed by right lower lobectomy. Pathological examination proved that the resected lesion was an arterial aneurysm. Patchy arteriosclerotic change was present in the intima of the aneurysm, but there was no evidence of inflammatory change in the arterial wall and the adjacent alveoli and bronchi. Twenty-six cases of bronchial artery aneurysm have been previously reported in the literature, but this is the first case that appeared as a solitary nodule on conventional chest X-ray.

Aneurysm↗