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Biomedical subjects

K Masuda

Publications and source records attributed to K Masuda.

At least 505 records · Page 28Linked to original sources
PubMed1991

[Multivariate analysis for the prediction of recurrence in colorectal cancer].

We developed a predictive scale for cancer recurrence by conducting a multivariate analysis (Hayashi's discriminant analysis of qualitative data) on clinicopathologic indicators in 207 patients with Dukes' B or C colorectal cancer who underwent curative resection at our institution. Seven indicators were found to have prognostic value. Nodal status, which was divided into five categories according to the level and number of positive nodes, had the highest coefficient as a predictor of recurrence. The correlation ratio between the group showing recurrence and that showing non-recurrence was 0.49, with 74% discrimination success rate. Liver or lung metastases were more accurately discriminated than local or peritoneal failure. We assessed the accuracy of this predictive scale in 110 patients with Dukes' B or C colorectal cancer who had been surgically treated at another institution (National Cancer Center, Tokyo), and determined it to be 68%. We think that this scale using multivariate analysis for the prediction of cancer recurrence has significant clinical application in the selection of more effective postoperative adjuvant chemotherapy. It is concluded that the present predictive scale is clinically useful, but that the inclusion of other indicators such as immunohistological ones is required to increase its predictive precision.

Colorectal Neoplasms↗
PubMed1991

Colorectal carcinomas incidentally detected in autopsied cases and inpatients.

During the past 20 yr, 17 colorectal carcinomas (0.47%) were incidentally detected among 3,638 autopsied patients without clinically evident colorectal carcinoma, including 2,232 males and 1,406 females, more than 40 yr old. Among the 15 male and two female index subjects, six (0.33%) were detected in the first and 11 (0.60%) in the second decade. During their survival periods, fecal occult blood studies were performed in 14 cases and positive in 12 (86%); however, two of them had gastric ulcers which were responsible for the occult blood. During the recent 11 yr, six cases (0.48%) of colorectal carcinoma (four of them males; two, females) also were detected among 1,249 inpatients who were examined by barium enema and/or colonoscopy, including 816 males and 433 females, 40 yr old, or more, in the Department of Radiology. Fecal occult blood was detected in four cases (67%) before colonic investigation. Compared with 708 surgically resected carcinomas, the incidental lesions from both sources were smaller, consisted of higher percentages of Dukes' A type, and arose predominantly from the sigmoid colon and, rarely, from the rectum. These results indicate that the prevalence of colorectal carcinoma and its predominance in the sigmoid colon have not only apparently but actually increased in Japan, apart from improved diagnostic capabilities, and that false-negative rates with occult blood tests were surprisingly low in these autopsied cases and inpatients.

Aged↗
PubMed1991

Production of cytokines by chondrocytes and its role in proteoglycan degradation.

Increased populations of interleukin 1 (IL-1), tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6) and stromelysin (MMP-3) positive chondrocytes were found in osteoarthritic cartilage with immunoperoxidase microscopy using monospecific antibodies. Chondrocytic cytokine and MMP-3 productions were confirmed with tissue cultures of human osteoarthritic and healthy cartilage and monolayer cultures of rabbit articular chondrocytes. IL-6 production was induced by IL-1 alpha and TNF-alpha. The effects of these cytokines on proteoglycan degradation was also studied. While IL-1 alpha and TNF-alpha accelerated proteoglycan release and caseinase production by chondrocytes, IL-6 had no effect by itself and even depressed the effect of IL-1 alpha. Our results suggest that the cytokine network plays a crucial role in the chondrocyte mediated breakdown of cartilage.

Animals↗
PubMed1990

[The management of stage I lymphomas of the T-cell type].

Between 1980 and 1988, we treated 68 patients with clinical stage I non-Hodgkin lymphomas. Fifteen patients had lesions classified as T-cell type lymphomas, and the remainder as B-cell type lymphomas. The actuarial 5-year survival rate was 42% for patients with T-cell type and 78% for patients with B-cell (p less than 0.03), and freedom from relapse was 25% and 67%, respectively (p less than 0.01). The main relapse sites for patients with T-cell type were extranodal (5 patients) and multiple sites (2 patients). These results suggest that patients with T-cell type lymphomas should be treated by aggressive combination chemotherapy as well as radiotherapy, even though their disease may appear to be limited to one region.

Female↗
PubMed1990

[Radiotherapy and chemotherapy in stages I and II non-Hodgkin's lymphomas of Waldeyer's ring].

Sixty-four patients with stages I and II non-Hodgkin's lymphomas (NHL) involving Waldeyer's ring treated between 1970 and 1987 were reviewed. Patients with stage II NHL were subdivided into stage II 1 (limited type) and stage II2 (advanced type) from the state of neck nodes. Stage II1 was defined as involvement of unilateral cervical nodes less than 4 cm in diameter as well as Waldeyer's ring involvement. Other stage II cases were classified as stage II2. All 17 patients with stage I NHL were treated with radiation therapy alone. Their diseases were well controlled, and none of them died of causes related to the lymphoma. Among 14 patients with stage II1 NHL, the 5-year survival rate for the 9 patients treated with radiation therapy alone was 87.5%. Until 1982, 19 of 21 patients with stage II2 NHL treated with radiation therapy alone or radiation therapy and adjuvant chemotherapy (VEMP or COPP) died within 5 years mainly of disseminated diseases. Since 1983, CHOP has been used as the main treatment as well as radiotherapy for the 12 stage II2 NHL patients. So far, only 3 of them relapsed and 2 of them died of causes related to the lymphoma. Only 1 of these 12 patients was T-cell lymphoma compared to 7 of 9 stage II2 patients before 1982. This suggests that patients with stage I and those with limited stage II can be safely treated with radiotherapy. Also aggressive chemotherapy as well as radiotherapy should be used for patients with advanced stage II NHL involving Waldeyer's ring.

Adult↗
PubMed1990

Comparison of I-123 IMP and Tc-99m HMPAO SPECT studies with PET in dementia.

We compared I-123 IMP and 99m-Tc HMPAO SPECT studies with 0-15 H2O and F-18 FDG PET studies, and evaluated the clinical significance of SPECT studies in dementia. Seventeen patients including 9 patients with Alzheimer's disease, 3 patients with Pick's disease and 5 patients with multi-infarct dementia were studied. IMP and HMPAO SPECT studies could not detect mildly affected areas when compared with FDG PET. However, they revealed decreased perfusion in the bilateral parietal regions in Alzheimer's disease and in the bilateral frontal regions in Pick's disease, while MRI and/or CT showed mild to moderate cerebral atrophy. IMP and HMPAO SPECT studies can be easily performed in clinical practice, and these findings were useful in the differential diagnosis of dementia. Our preliminary results suggested that SPECT studies with I-123 IMP and Tc-99m HMPAO, despite their limitations, are useful in the differential diagnosis of dementia.

Aged↗
PubMed1990

Bone growth retardation induced by single and multifractionated irradiation.

The right hind legs of 12- to 14-week-old mice were exposed to single and multifractionated courses of gamma-ray irradiation. The recovery curves, time-dose relationships, and fraction number-dose relationships were analyzed using femoral growth retardation as an endpoint. The bones grew 2 mm, about a 10% increase over their original lengths, in 12 months; and 63% and 85% in volume in 6 and 12 months, respectively. The ratio of the volume increase of the irradiated right leg per unit time, the actual growth, to the volume increase of the non-irradiated left leg, the potential growth, was calculated for each mouse. The doses necessary to produce a given degree of bone growth retardation in 50% of the tested animals were calculated for each treatment schedule. The isoeffect doses for a given degree of bone growth retardation after 2 and 4 equal fractionation exposure increased (peak at one day-interval) and decreased (trough at 2-day interval), and later increased additionally with increasing time intervals between doses.

Animals↗
PubMed1990

The efficacy of combined treatment with recombinant human tumor necrosis factor-alpha and 5-fluorouracil is dependent on the development of capillaries in tumor.

The antitumor effects of recombinant human tumor necrosis factor-alpha (rTNF-alpha) and 5-fluorouracil (5-FU) in combination treatment were examined on Meth A fibrosarcoma implanted intradermally in mice. Growth of the tumor was inhibited when rTNF-alpha was given i.v. on day 7 or 11 after implantation, but the effect was countered when 5-FU was additionally given i.p. once a day on days 1-4 after implantation. Conversely, 5-FU given on days 5-8 after implantation augmented the antitumor effects of rTNF-alpha. Injection of carbon particles showed that fine capillaries did not develop in the tumors of mice treated with 5-FU on days 1-4 after implantation, but that a delicate network of capillaries developed in the tumors of both the mice treated with 5-FU on days 5-8 after implantation and the controls given saline. The results show that the timing of 5-FU treatment is important when attempting to enhance the antitumor effects of rTNF-alpha, and suggest that these effects are directly associated with newly formed fine capillaries in the tumor.

Animals↗
PubMed1990

Differential diagnosis of bilateral parietal abnormalities in I-123 IMP SPECT imaging.

This report discusses the clinical significance of bilateral parietal abnormalities on I-123 IMP SPECT imaging in 158 patients with cerebral disorders. This pattern was seen in 15 out of 21 patients with Alzheimer's disease; it was also seen in 4 out of 5 patients with Parkinson's disease with dementia, in 3 out of 17 patients with vascular dementia, in 1 out of 36 patients with cerebral infarction without dementia, in 1 out of 2 patients with hypoglycemia, and in 1 out of 2 patients with CO intoxication. Detection of bilateral parietal abnormalities is a useful finding in the diagnosis of Alzheimer's disease, but one should keep in mind that other cerebral disorders may also show a similar pattern with I-123 IMP SPECT imaging.

Aged↗
PubMed1990

Neuronal migration anomalies causing extensive ventricular indentation.

Neuronal migration disorders include various anomalies of the brain, and cortical heterotopia is the most common type. In this report, we present the radiological findings of two adults with unusually large cortical heterotopia associated with fused-lip schizencephaly that caused extensive ventricular indentation. The lesion showed density on a computed tomographic scan and signal intensity on a magnetic resonance imaging scan similar to normal gray matter. Perifocal edema, contrast enhancement, and calcification were not seen. An abnormally decreased volume of the ipsilateral cerebral hemisphere, the presence of adjacent microgyri, and deep fissures that contained blood vessels were also characteristic findings, indicating abnormal development. Knowledge of this entity is important in differentiating true intracerebral neoplasms.

Adult↗
PubMed1990

Cerebral hemodynamic change in the child and the adult with moyamoya disease.

To clarify the differences in cerebral hemodynamics and metabolism between children and adults with bilateral moyamoya disease, we measured regional cerebral blood flow, regional oxygen extraction fraction, regional metabolic rate for oxygen, regional cerebral blood volume, and regional transit time using positron emission tomography in nine patients (five children and four adults) and compared the values with those in controls (four children with unilateral moyamoya disease and six normal adults). The major differences between pediatric and adult patients were in regional cerebral blood volume and regional oxygen extraction fraction. Regional cerebral blood volume was more markedly increased relative to the control value in the children than in the adults. Also, regional oxygen extraction fraction was greater than control in areas with low blood flow in the children but was never increased in the adults. However, in the adults, only regional transit time was significantly prolonged relative to the control values. The increased regional oxygen extraction fraction relative to the control value observed in children with moyamoya disease may explain why transient ischemic attacks are a common symptom in this group.

Adolescent↗
PubMed1990

Specific metabolic activation of FK973, a new antitumor antibiotic, in L1210 leukemia cells.

FK973 (11-acetyl-8-carbamoyloxymethyl-4-formyl-14-oxa-1,11- diazatetracyclo[7.4.1.O2,7O10,12]tetradeca-2,4,6-trien -6,9-diyl diacetate), a new substituted dihydrobenzoxazine, has potent cytotoxic and antitumor effects on murine and human tumors in vivo and in vitro, and forms interstrand DNA-DNA and DNA-protein cross-links after being activated in the cytoplasm. In this study, the mechanism(s) by which FK973 is activated in the cytoplasm of in vitro cultured murine L1210 leukemia cells were studied using compounds that affect monoamine oxidase. When the cells were incubated with an antitumor drug and the compounds, tranylcypromine, benzylamine, phenylethylamine and tyramine of the many compounds tested reduced the cytotoxicity of FK973, but not that of mitomycin C or cisplatin. These compounds also suppressed the formation of interstrand DNA-DNA cross-links with FK973 in the cells, but did not suppress cross-links with mitomycin C or cisplatin. The incorporation of 14C-FK973 into the cells was not affected by these compounds. The results suggest that FK973 is activated by some drug-metabolic system(s) in the cytoplasm to form interstrand DNA-DNA cross-links, and induces cytotoxicity against the cells. This activation of FK973 in the cytoplasm is discussed in connection with the drug-metabolic system(s) in relation to the structures of the compounds.

Animals↗
PubMed1990

[Nephrotoxicity of cefpirome sulfate in rabbits--single and multiple intravenous administration].

Nephrotoxic potential of cefpirome sulfate (CPR) was examined by single and multiple intravenous administrations to Japanese white male rabbits. In single administration studies, no nephrotoxic symptoms were observed at the dose level of 320 mg/kg of CPR or less. At the dose level of 500 mg/kg or more, nephrotoxic findings were noted in both CPR and cefazolin sodium(CEZ) groups, such as proteinuria, glucosuria, increase in serum level of urea nitrogen, creatinine and uric acid, and necrosis and calcification in the proximal tubular epithelium of kidney. Renal phenolsulfonphthalein(PSP) excretion was suppressed at the dose level of 500 mg/kg of CPR or more, and 2000 mg/kg of CEZ. In 14 and 21 days repeated administration studies, no nephrotoxic symptoms were observed at the dose level of 100 mg/kg of CPR and CEZ or less. At the dose level of 200 mg/kg of CPR or more, urinary and serum biochemical findings mentioned above were observed, and histopathological changes in the kidney described above were added in 400 mg/kg group. The similar nephrotoxic symptoms including histopathological changes of the kidney were observed in the groups of 100 mg/kg of cefaloridine(CER) and 200 mg/kg of CEZ. In addition, renal PSP excretion was suppressed in the group of 200 mg/kg of CEZ. The results would suggest that CPR is less nephrotoxic than CER and that the nephrotoxic potential of CPR is comparable to CEZ because CPR caused more severe renal failures in single administration study and less severe renal failures in multiple administration study than CEZ.

Animals↗
PubMed1990

Influences of TV games on physical and psychological development of Japanese kindergarten children.

The present study was an investigation of playing a TV game and its influences on physical and psychological development of kindergarten children. A self-completed questionnaire was delivered to the parents of 426 children. Of these, 408 had fully completed answers. Questions regarded the amounts of TV game play, its influences on health and on development of children and the attitudes of parents toward the game. Analysis indicated that the kindergarten children, especially boys, played frequently and both the percentage of players and the number of playing hours increased with age. Few adverse effects were reported on vision or other aspects of physical health. Children who played the game had much higher scores on sociability than those with no experience. This seemed to reflect that children acquired a new repertoire of plays from the TV game.

Child Behavior Disorders↗
PubMed1990

[Screening for gynecologic cancer].

Results of mass screening for cervical cancer, endometrial cancer and breast cancer in Miyagi Prefecture were presented. Systems of screening for endometrial cancer and breast cancer are now arranging in Japan.

Adult↗
PubMed1990

[Radiation enteritis: mucosal regeneration and stromal reaction of the small intestine after irradiation].

D-glucose absorption in vivo in mice decreased as a function of dose and time after irradiation returning to normal within a week after irradiation. The lamina propria is seen full of polymorphonuclear leukocytes, other infiltrative cells, capillary and lymphatic network, which seem closely related to chronic enteritis. Since acute and chronic diarrhea after irradiation can be reduced by cholestyramine or acetylsalicylate, malabsorption of bile salts or prostaglandin E of the luminal content has been regarded as a cause of radiation-induced diarrhea. LD 50 of irradiated mice was increased by SOD. From the clinical data, thin physique, previous operation, and total dose of more than 50 Gy could be predisposing factors of radiation-related enteritis.

Adult↗
PubMed1990

Distraction arthroplasty of the hip by bicentric femoral head prosthesis.

Distraction arthroplasty of the hip with bicentric femoral head prosthesis was performed on 18 hips with advanced secondary osteoarthritis. This method of hip arthroplasty consists of reconstruction of the deformed acetabulum into the dome-shaped acetabulum, replacement of the femoral head by the bicentric femoral head prosthesis, and postoperative continuous long-axis traction to the lower extremity. Postoperative physical therapy is performed on the assumption that the articular cartilage is formed in a narrow empty space between the articular surfaces made by continued application of distraction to the hip. In distraction arthroplasty, the hip may regain a wide range of painless motion. Roentgenographically, the dome-shaped acetabulum was covered by a narrow radiolucent zone backed with a dense bone plate. The functionally remodeled structure of the hip was maintained during the follow-up period of six months to four years 11 months.

Acetabulum↗