Biomedical subjects

K Ohsato

Publications and source records attributed to K Ohsato.

At least 37 records · Page 2Linked to original sources

PubMed1995

[Radiotherapy for carcinoma of the esophagus in aged patients].

One hundred fifty-four patients with esophageal carcinoma were treated with either irradiation alone or irradiation combined with surgery at the University of Occupational and Environmental Health Hospital between January 1980 and February 1992. The number of patients 75 years old and older was 25. In patients 74 years old and younger, the overall five-year survival rate by Kaplan-Meier method was 24.5%. The survival rate was best in the patients who were treated by a combination of irradiation and surgery. In patients 75 years old and older, the one-year survival rate was 59%, and the three-year rate was 20%. Aged patients had a tendency to be worse in performance status, and there was no correlation between treatment modality and survival time. We conclude that radiotherapy is useful for treating esophageal cancer in aged patients particularly when maintenance of the quality of life is considered.

Adult↗

PubMed1994

Experimental carcinogenesis in the rat intestine induced by two different carcinogens--evaluation of carcinogenic action and its effect on ornithine decarboxylase activity.

Carcinogenesis in the rat intestine induced with 1,2-dimethylhydrazine (DMH), N-methyl-N-nitrosourea (MNU), and their combinatorial use was studied. Intestinal tumors, including both adenoma and adenocarcinoma, were induced in all the rats given the carcinogens. The tumor frequently occurred in the intestinal tract extending from the duodenum to the colon in the DMH treated group. In the MNU treated group, the tumor occurred in the colon, especially on the distal side. Distribution of tumors in the group treated with both carcinogens was similar to that seen in the MNU-treated group. Neither obvious macroscopic nor histological differences were observed between groups treated with these carcinogens. In addition, we investigated the effect of carcinogens on ornithine decarboxylase (ODC) activity in rat colon. Tumor tissues showed a remarkably high level of enzyme activity compared with the normal-appearing mucosa, and there was a correlation between the level of the ODC activity and the histological grade of malignancy. ODC activity in the normal-appearing mucosa of the carcinogens-treated rats was significantly higher than that of control rats, and the number of tumors per rat was correlated with the level of ODC activity. These results indicate that mucosal ODC may be a pertinent biological marker for local carcinogenic activity.

1,2-Dimethylhydrazine↗

PubMed1994

Regression of rectal polyps by indomethacin suppository in familial adenomatous polyposis. Report of two cases.

PURPOSE: The effect of indomethacin suppository on rectal polyps was evaluated in two patients with familial adenomatous polyposis who had undergone total colectomy and ileoproctostomy. METHODS: Both patients received intrarectal administration of 50 mg of indomethacin suppository once or twice daily to control the rectal remnant polyps. RESULTS: With this treatment, an almost complete regression was achieved within three months, in both patients. Polyps recurred after the interruption of indomethacin treatment in one patient. At the present follow-up of two to three years, no cancer has developed. CONCLUSIONS: Indomethacin suppository treatment was effective in controlling rectal remnant polyps in the two patients with familial adenomatous polyposis. Intraluminal administration of indomethacin in suppository form seems more beneficial since it allows for direct contact of the drug with the lesions and produces a high local concentration of the drug.

Adenomatous Polyposis Coli↗

PubMed1994

Direct evidence of neuron impairment by oral infection with verotoxin-producing Escherichia coli O157:H- in mitomycin-treated mice.

We developed a mouse model of acute encephalopathy induced by verotoxin 2 variant (VT2v)-producing Escherichia coli. Three-week-old mice were inoculated intragastrically with approximately 10(10) CFU of E. coli O157:H- strain E32511/HSC and simultaneously given an intraperitoneal injection of mitomycin (MMC; 2.5 mg/kg). Drinking water containing 5 g of streptomycin sulfate per liter was given ad libitum from 3 days before the infection. From 1 to 2 days after bacterial inoculation, clinical features including weight loss, weakness, and flaccid paralysis of the extremities developed, usually culminating in death within 4 days. Diarrhea was not observed during the course of disease. No mice died in the absence of streptomycin or MMC treatment for 2 weeks after the oral bacterial infection. Judging from the clinical course and the biochemical and histological examination, the cause of death was not likely to be attributable to renal failure or to a side effect of MMC. To better understand the cause of death, we examined the brain cortex and spinal cord of the moribund mice by electron microscopy. Mice showing mortal symptoms were given horseradish peroxidase intravenously. The tracer was present in the endothelial basal lamina, in the surrounding extracellular spaces, and even in the neuron fibers of the brain cortex. Furthermore, immunoreactivity of VT2v, proved by the use of rabbit anti-VT2 serum, was localized selectively in the damaged myelin sheaths of neuron fibers which were accompanied by edematous axons in the brain cortex and spinal cord. These findings strongly suggest that VT2v is toxic to both endothelial cells and neurons in the central nervous system and subsequently causes fatal acute encephalopathy.

Acute Disease↗

PubMed1994

Type IV collagen in hypertrophic cardiomyopathy.

Basement membrane of myocytes from patients with hypertrophic cardiomyopathy who died suddenly, seemed to be discontinuous by immunohistochemical methods. With the use of the sandwich immunoassay technique, we determined the frequency of type IV collagen and its influence on functional abnormality in 31 patients with hypertrophic cardiomyopathy and controls. Hypertrophic cardiomyopathy exhibited significantly increased serum type IV collagen compared with controls. A significant correlation was observed between serum type IV collagen and fractional shortening (r = -0.42 p < 0.05), and end-diastolic volume (r = 0.40 p < 0.05), DT (r = -0.50 p < 0.05). These data suggest that serum type IV collagen enhances clusters of cell-surface type IV collagen, including an alteration of the cytoskeleton, which may account for functional abnormalities in hypertrophic cardiomyopathy. Considering the fact that microscopic examination is unable to resolve the structure of the myocardial basement membrane, measurement of serum type IV collagen is thought to be useful in the diagnosis of myocardial basement membrane injury and the progression of hypertrophic cardiomyopathy.

Aged↗

PubMed1994

The healing process of chronic colitis in rats, induced by 2,4,6-trinitrobenzene sulfonic acid, with special reference to the role of fibronectin.

BACKGROUND: The healing process of rat chronic colitis was investigated to evaluate the role of fibronectin produced by fibroblasts in the healing tissue. METHODS: Chronic colitis was produced by intrarectal instillation of 2,4,6-trinitrobenzene sulfonic acid. The healing process was observed by light and electron microscopy and immunocytochemistry. Time course of fibronectin mRNA expression was measured by Northern blot hybridization. RESULTS: By light and electron microscopy, an abundance of young fibroblasts had gathered at the healing tissue and were involved in incorporation into the endothelium of the preexisting vessels, as vasoformative cells, and in transformation to new muscle cells in muscular regeneration. Such processes became pronounced from day 3 and persisted for 6 weeks. Immunocytochemical data showed that fibronectin, produced in the rough endoplasmic reticulum of the fibroblasts and released to the extracellular surface, played inductive roles in the movement and aggregation of such cells and in their contacts with neighboring endothelial cells of the preexisting capillaries. Northern hybridization showed that mRNA coding for fibronectin rapidly reached maximum on day 3 and gradually decreased almost to the control level at 6 weeks. CONCLUSIONS: These observations elucidate the role of young fibroblasts, as multipotent cells, and of fibronectin in acceleration of the healing process in this model of chronic colitis.

Animals↗

PubMed1994

[Intracranial foreign body granuloma caused by fine cotton fibers: a case report].

Reported here is a rare case of intracranial foreign body granuloma caused by fine cotton fibers originating from the cotton sheet, which was used in the previous operation. The patient was a 54-year-old woman who presented with headache and right hemiparesis. CT scan demonstrated a large enhanced tumor in the left temporal lobe. During the operation, the tumor bled easily and was hard to remove. The brain surface was covered with oxidized cellulose (Oxycell) after the tumor was subtotally removed. Cotton sheets (Surgical Patty) were also used during the operation. The microfibrillar collagen hemostat (Avitene) was not applied. The histological diagnosis was astrocytoma. Radio-chemotherapy was given. CT and MRI on the 40th day after the operation, showed a large tumor in the left temporal lobe, which led to suspicions of tumor recurrence. The second operation disclosed a mass which was harder in consistence than the previous one. The histological diagnosis was foreign body granuloma, which contained a lot of fine cotton fibers. Oxycell was not found in it. The cotton-sheet is well documented as a cause of granuloma in the literature, but it is seldom mentioned that the foreign body granuloma is caused by cotton fibers, scattered in the operative fields. This case report suggests the possibility of cotton-fiber granuloma and our simple experiment indicated that a lot of cotton fiber might be scattered in the operative fields, if dry cotton sheets are used. These results stress that washed cotton sheets should be applied to avoid the possibility of the development of cotton-fiber foreign body granuloma.

Adult↗

PubMed1994

Multicentre randomised study of adjuvant chemotherapy with mitomycin C and tegafur or tegafur-uracil in gastric cancer.

OBJECTIVE: To compare therapeutic results and five year survival after two regimens of adjuvant chemotherapy after resections for gastric cancer. DESIGN: Prospective randomised multicentre trial. SETTINGS: 21 departments of surgery. SUBJECTS: 243 patients with stage II, III, or IV gastric cancer. INTERVENTIONS: All patients received an intravenous bolus of mitomycin C 20 mg on the day of operation, and 10 mg on the first postoperative day. They were then randomised to receive either tegafur 600 mg or tegafur-uracil 600 mg orally daily beginning two weeks after operation and continuing for two years. Patients with histological confirmed stage IV disease also received mitomycin C 10 mg every three months starting one month after operation. MAIN OUTCOME MEASURES: Survival and side effects. RESULTS: 13 patients (5%) were withdrawn from the study, leaving 230 for analysis. There were no serious side effects and both drugs were safe when given continuously for two years. There were no significant differences in 5 year survival (though patients who were given tegafur-uracil tended to live longer), except when patients who had histological curative resections were compared with and those with poorly differentiated adenocarcinoma (p = 0.04).

Adult↗

PubMed1993

Immunoelectron microscopy on the localization of endothelin in the umbilical vein of perinatal rabbits.

Immunoelectron microscopic localization of endothelin (ET) using the mouse monoclonal anti-ET sera was performed on the pre- and postnatal rabbit umbilical vein during stages when Weibel-Palade (WP) bodies increase in number in the endothelial cells. The immunoreactions are localized in the rough endoplasmic reticulum, Golgi cisterns, and WP bodies that are actively segregated from the Golgi apparatus. After degranulation and extracellular release of WP bodies was induced by compound 48/80, heavy immunoreactions were seen in both vascular lumen and cytoplasm near the degranulated WP bodies. These results indicate that ET is stored in WP bodies after segregation from the Golgi apparatus and released from the endothelial cells concomitantly with other components of these granules by exocytosis. Because the immunoreactions are also seen in pinocytotic vesicles that are occasionally in contact with WP bodies, it seems likely that WP bodies are also involved in the uptake and storage of ET from blood plasma.

Animals↗

PubMed1993

Turcot's syndrome and familial adenomatous polyposis associated with brain tumor: review of related literature.

We investigated clinical manifestations in 124 patients with a possible Turcot's syndrome whose data were taken from documented cases. The cases were subclassified mainly on the bases of the type of familial occurrence and listed in five Tables. We searched for differences in colonic manifestation, histologic type of glioma, mode of inheritance, frequency of parental consanguinity, skin lesions and other accompanying lesions among these five groups. The differences of these clinical findings suggested that glioma-polyposis syndrome should be classified as follows; (1) cases of Turcot's syndrome who had characteristic colonic and brain manifestations, (2) cases of FAP associated with glioma, (3) suspicious cases of glioma-polyposis, and (4) cases other than glioma-polyposis syndrome.

Adenomatous Polyposis Coli↗

PubMed1993

Benign schwannoma in the hepatoduodenal ligament: report of a case.

A 62-year-old woman with a large mass in the hepatic hilus underwent surgery. Histologically the tumor was predominantly composed of spindle-shaped cells with nuclear palisading and cells that stained positively for S-100 protein. The diagnosis was benign schwannoma (neurilemoma). The presence of lymphoid cuffing with lymphoid follicles in the capsule and xanthomatous change differed from conventional soft parts schwannoma and closely resembled benign schwannoma in the gastrointestinal tract.

Bile Duct Neoplasms↗

PubMed1993

[Advancement in the diagnosis of disseminated intravascular coagulation for the surgeon].

A brief explanation of the molecular markers of coagulation, fibrinolysis and endothelial cell activation was done. The clinical significance of markers, such as, soluble fibrin monomer complex, FDP D-dimer, prothrombin fragment 1 + 2, thrombin-antithrombin III complex, plasmin-alpha 2 plasmin inhibitor complex and plasma thrombomodulin in our patients with disseminated intravascular coagulation (DIC) due to abdominal sepsis and malignancy is discussed. The coagulopathy in the DIC patients due to abdominal sepsis had a different aspect from that in the DIC patients due to malignancy. Activation of the coagulation and fibrinolytic systems in sepsis was milder than that in malignancy, despite the decrease of antithrombin III activity in the patients with sepsis. In the patients with sepsis, granulocyte elastase was increased. It was proposed that the coagulopathy was caused not only thrombin formation but also by granulocyte proteinase. It could be expected that the pathophysiology of disseminated intravascular coagulation should be clarified, because of the high sensitivity.

Antifibrinolytic Agents↗

PubMed1992

Antihepatitis C virus status in hepatocellular carcinoma and the influence on clinicopathological findings and operative results.

Antihepatitis C virus (HCV) status was investigated in 100 patients undergoing hepatectomy for hepatocellular carcinoma (HCC) between 1980 and 1989. The clinicopathological findings and operative results, in patients with or without HCV marker, were compared retrospectively. The positivity rate of anti-HCV was 51 per cent. In this group there was a higher mean age, fewer symptoms, raised alanine aminotransferase level, higher 15-min indocyanine green clearance rate and earlier tumour stage compared with the anti-HCV negative group. Positive tumour margins and vascular invasion were seen less frequently in the anti-HCV positive group. HCC with HCV marker showed characteristic features of chronic non-A non-B hepatitis and of HCC originating from liver cirrhosis. There was a better cumulative 1-year survival rate for anti-HCV positive patients, but 3- and 5-year survival rates after hepatectomy were similar in both groups. Although HCV-related HCC had typical features of chronic non-A non-B hepatitis and a relatively early stage of tumour, biological features and operative results were similar with or without the HCV marker.

Adult↗

PubMed1992

Coagulopathy in disseminated intravascular coagulation due to abdominal sepsis: determination of prothrombin fragment 1 + 2 and other markers.

To estimate the degree of coagulopathy in abdominal sepsis, we measured the plasma levels of prothrombin fragment 1 + 2 (F1 + 2), thrombin-antithrombin III complex (TAT) and plasmin-alpha 2-plasmin inhibitor complex (PIC) by the enzyme-linked immunosorbent assay in 38 patients with disseminated intravascular coagulation (DIC). In 20 patients with DIC due to abdominal sepsis, plasma levels of F1 + 2, TAT and PIC were 2.6 nmol/l, 27.9 micrograms/l and 1.5 micrograms/ml, respectively, with a mean antithrombin III (AT III) activity of 41.7%. F1 + 2, TAT, PIC and AT III levels were 4.7 nmol/l, 75.8 micrograms/l, 8.8 micrograms/ml and 70.9% in 18 patients with DIC as the result of malignancy. Though AT III levels in DIC due to sepsis were lower than those in DIC due to malignancy, the levels of F1 + 2, TAT and PIC in the former were not significantly more increased than those in the latter. The plasma levels of F1 + 2 were positively correlated with TAT and PIC in DIC patients with malignancy; however, there was no correlation between F1 + 2 and TAT or PIC in DIC patients with sepsis. In addition, the levels of serum albumin in the two groups were similar. These results suggest that activation of coagulation and fibrinolytic systems may not be so prominent in cases of DIC due to abdominal sepsis, compared to related events in DIC due to malignancy. It is also suggested that the depletion of AT III in cases of sepsis is not only caused by a consumption related to intravascular coagulation or to an alternate distribution of protein.(ABSTRACT TRUNCATED AT 250 WORDS)

Antifibrinolytic Agents↗

PubMed1992

Histopathological factors related to diastolic function in myocardial hypertrophy.

To clarify the histopathologic influence on diastolic function in the hypertrophied heart, we compared the echocardiographic and histopathologic findings in 9 controls, 10 patients with hypertrophic cardiomyopathy (HCM), and 8 hypertensive patients with asymmetric septal hypertrophy (HT-ASH). M-mode echocardiography was used to determine the left ventricular diastolic function. Mean diameter of myocytes, percentage of fibrosis and disarrangement were quantitatively calculated from right ventricular endomyocardial biopsy specimens. In both HT-ASH and HCM, the isovolumic relaxation time was significantly longer and the rapid filling volume tended to be smaller than in the controls. Histopathologically, the mean diameter of myocytes and percentage of myocardial interstitial fibrosis did not differ significantly between HT-ASH and HCM. However, quantitative disarrangement of myocytes in HCM was significantly greater than that in HT-ASH. Multiple regression analysis showed that the percentage of fibrosis was the most significant factor related to diastolic left ventricular dysfunction in HT-ASH, while disarrangement of myocytes was the most significant in HCM. We conclude that diastolic dysfunction in HT-ASH can be attributed to the percentage of fibrosis, and to disarrangement of myocytes in HCM.

Adult↗

PubMed1992

Methyldopa-induced colitis in a patient with membranoproliferative glomerulonephritis.

A 76-year-old man with membranoproliferative glomerulonephritis complicated by methyldopa-induced colitis is reported. Eight months after administration of methyldopa, mucous bloody stool was noted. A barium enema examination showed disappearance of haustra and a spastic rectosigmoid with pseudo-polyposis. Biopsy specimens obtained from the sigmoid mucosa revealed interstitial edema and small inflammatory cells. After cessation of methyldopa treatment, the sigmoid findings, blood pressure, and proteinuria were improved, suggesting that methyldopa not only induced the acute colitis but also worsened the nephrotic syndrome in this patient.

Acute Disease↗

PubMed1992

Sweet's syndrome associated with subacute necrotizing lymphadenitis.

A 34-year-old man with Sweet's syndrome associated with subacute necrotizing lymphadenitis is reported. Histological examination of an erythematous, painful, cutaneous plaque revealed a dermal interstitial neutrophilic infiltrate. A biopsy specimen obtained from an inguinal lymph node showed granulomatous formation, consisting of histiocytes, with central necrosis in the paracortex and macrophages in the sinus. Although the causes of the two diseases remain obscure, this appears to be the first report of Sweet's syndrome associated with subacute necrotizing lymphadenitis.

Adult↗

PubMed1992

[Therapeutic value of hepatectomy and transcatheter arterial embolization (TAE) for hepatocellular carcinoma].

Therapeutic value of hepatectomy and TAE was evaluated retrospectively in 150 hepatectomized and 117 non-hepatectomized patients of hepatocellular carcinoma (HCC). Operative death was seen in 5 patients. Cumulative 5 years survival rate and disease free cumulative 5 years survival rate of the 145 hepatectomized patients were 35.4 per cent and 23.6 per cent respectively. These survival rates were significantly affected by tumor size, intrahepatic metastasis (IM) and vascular invasion (Vp). But the influences of tumor margin (TW) and curative resection (relative curative or relative non-curative) were slight. Ninety-two patients (69:dead, 23:alive) had tumor recurrences. TAE was performed in 56 out of 92 patients effectively and 2 years survival rate was 31.5 per cent. Overall cumulative 5 years survival rate of non-hepatectomized patients was 6.6 per cent, but this group showed a more reduced hepatic reserve and more advanced tumor stage. Six patients treated by TAE survived more than 4 years. Hepatectomy is a first option for the treatment of HCC since complete cure may be estimated. However, because of operative risk and higher recurrence rate, use of current multidisciplinary treatment including TAE is necessary for the prognostic improvement of HCC with or without hepatectomy.

Aged↗