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J Sakamoto

Publications and source records attributed to J Sakamoto.

At least 73 records · Page 4Linked to original sources
PubMed1997

Cold snare excision is a safe method for diminutive colorectal polyps.

Cold snare excision (CSE) has proved to be an effective method for the destruction of diminutive polyps of the colon and rectum. We investigated the correlation between polyp size and bleeding time at the resected end after CSE, and also an appropriate measuring method using CSE. Eighty patients with single polyps were examined. Each polyp was identified as being 5 mm in diameter or smaller using the open-biopsy forceps technique (OBFT). The size of the polyp was calculated using our measuring system (SMS). Of the polyps identified as being 5 mm in diameter or less using OBFT, 15% were 6 mm or more using the SMS. CSE was performed for each polyp, and the time taken for the hemostasis (bleeding time of the CSE; BTCSE) was determined. In seventy-seven polyps that were 6 mm or smaller in SMS, a correlation was noted between SMS and BTCSE. In three polyps that were 7 mm or more by SMS, hemostasis took 10 min or more after CSE, and required electrocoagulation. These results suggest that CSE is a safe method for the removal of polyps determined to be 6 mm in diameter or smaller using the SMS.

Aging↗
PubMed1997

Analysis of specific accumulation of radiolabeled anti-carcinoembryonic antigen monoclonal antibody CEA 102 in colorectal cancer using computed radiography.

The specific accumulation of radiolabeled anti-carcinoembryonic antigen (CEA) monoclonal antibody (MoAb) CEA 102 in colorectal cancers was investigated by autoradiography of surgical specimens using Fuji Computed Radiography (FCR). Five patients with colorectal cancer were injected intravenously with [13I]-labeled intact CEA 102 or its F(ab')2. Primary tumor and liver metastases were successfully detected by external scanning with gamma camera in four cases. Autoradiographic study using FCR showed predominant localization of [13I]-labeled CEA 102 in primary tumors and liver metastases in all cases. Even the small-sized liver metastasis (0.5 cm) was clearly visualized. The pixel distribution curves showed the heterogeneity of the distribution of administered MoAb in the tumors. In the quantitative distribution analysis of CEA 102, the uptake of the primary tumor was 10-fold greater than that of the normal colon mucosa. These results suggest that MoAb has great potential in radioimmunodetection as well as possible use in antibody-directed therapy.

Antibodies, Monoclonal↗
PubMed1996

Cytochrome bd-type quinol oxidase in a mutant of Bacillus stearothermophilus deficient in caa3-type cytochrome c oxidase.

Gram-positive thermophilic Bacillus species contain cytochrome caa3-type cytochrome c oxidase as a terminal oxidase in the respiratory chain. To identify alternative oxidases, we isolated B. stearothermophilus mutants defective in the caa3-type oxidase activity. One mutant contained little cytochrome a and had low cytochrome c oxidase activity. However, growth and the respiratory activity of membranes in the presence of NADH were close to normal, suggesting that the mutant contains an alternative electron transfer pathway. A novel oxidase was isolated from the membrane fraction of the mutant. The enzyme is a cytochrome bd-type quinol oxidase composed of two subunits of 52 and 40 kDa, whose N-terminal regions show sequence similarity to polypeptides of the bd-type oxidase from Escherichia coli and Azotobacter vinelandii. This is the first report of a bd-type terminal oxidase purified from a Gram-positive bacterium.

Amino Acid Sequence↗
PubMed1996

Prognostic value of preoperative immunosuppressive acidic protein in patients with gastric carcinoma. Findings from three independent clinical trials. Tumor Marker Committee for the Study Group of Immunochemotherapy with PSK for Gastric Cancer.

BACKGROUND: Immunosuppressive acidic protein (IAP) has been reported to have close correlation with the impairment of host immune response. To evaluate the significance of IAP in clinical studies, the prognostic value of preoperative IAP was investigated in clinical trials of patients with gastric carcinoma after curative resection. METHODS: An appropriate IAP threshold value of 580 micrograms/mL was determined using Cox's proportional hazards model. Five-year survival rates were estimated for high and low IAP groups in three different clinical studies. Meta-analysis was performed based on individual patient data, and summarized hazard ratios were estimated using a stratified proportional hazards model. RESULTS: Meta-analysis of the three clinical trials demonstrated that patients with preoperative IAP levels above the threshold had significantly poorer cancer related survival (P = 0.0039) and absolute survival (P = 0.0023), even after adjustment for the major prognostic factors. CONCLUSIONS: Gastric carcinoma patients with an IAP value above the threshold level of 580 micrograms/mL have a higher risk of cancer death and absolute death than patients with an IAP value below the threshold value.

Adult↗
PubMed1996

Nucleotide and amino acid sequences for cytochrome caa3-type oxidase of Bacillus stearothermophilus K1041 and non-Michaelis-type kinetics with cytochrome c.

A pseudo-sigmoidal cytochrome c-dependence curve of oxidase activity was observed with cytochrome oxidase from the Bacillus stearothermophilus strain K1041, while the other thermophilic Bacillus PS3 which has been extensively studied possessed normal Michaelis-Menten type kinetics. The genes coding for four subunits of cytochrome caa3-type oxidase and for heme O synthase were isolated from a genomic DNA library of K1041 by using a PS3 DNA fragment containing the highly-conserved region of the largest subunit as a probe, and sequenced. Most residues in subunits I (COI/caaB product), III (COIII/caaC product), and IV (COIV/caaD product) of K1041 were highly conserved when compared with those of PS3. However, the sequence of K1041 subunit II (COII/caaA product) was distinctly different from that of the PS3 subunit II. These Bacillus COIIs have an additional sequence for cytochrome c after the CuA binding protein portion with two transmembrane segments which is homologous to the mitochondrial counterpart, and represents the site of electron ingress. Several charged residues in the vicinity of cytochrome c moiety are replaced by oppositely charged residues. It is likely that these amino acid replacements in subunit II are the cause of the abnormal sigmoidal saturation curve for extrinsic cytochromes c of the K1041 enzyme.

Amino Acid Sequence↗
PubMed1996

Immunohistochemical analysis of the poorly differentiated stomach adenocarcinoma with medullary growth pattern.

Poorly differentiated gastric adenocarcinoma with medullary features (poor medullary) is distinguished by a propensity for hepatic metastasis. To classify it antigenically, we compared it to poorly differentiated adenocarcinoma with scirrhous growth pattern (poor scirrhous), well and moderately differentiated adenocarcinoma (differentiated adenocarcinoma), and normal gastric mucosa (foveolar and deep epithelium) using immunohistochemistry with antibodies against CEA, AFP, NSE, and Lewis-type antigens. Lewis(a) antigen was significantly associated with differentiated adenocarcinoma and foveolar epithelium, although Lewis(x) antigen was significantly expressed in poor medullary, poor scirrhous, and deep gland epithelium. From the viewpoint of expression of Lewis(a), there was no significant differentiation between poor medullary and differentiated adenocarcinoma, but it was definite between poor scirrhous and differentiated adenocarcinoma. Therefore, we conclude that in antigenic expression, poor medullary carcinoma is allied with differentiated adenocarcinoma rather than poorly differentiated scirrhous carcinoma.

Adenocarcinoma↗
PubMed1996

The effectiveness of medroxyprogesterone in the treatment of multiple metastasizing leiomyosarcomas: report of a case.

A 51-year-old woman was admitted to our hospital for further investigation of chest X-ray films which showed multiple shadows that had been growing slowly over 2 years. Her only symptom was hemosputa. The lesions were suspected of being metastasizing leiomyoma due to her past history of uterine leiomyoma. Just 1 week before undergoing scheduled open lung biopsy, the lung lesions increased remarkably in size and number. A thoracotomy was performed and six of the numerous nodules were removed. The resected specimens were pathologically diagnosed as metastasizing leimyosarcoma which was positive for the progesterone and estrogen receptors. Thus, 1 month postoperatively, a course of medroxyprogesterone (MPA), 600 mg daily, was commenced. The residual lesions in her chest started to diminish, shortly afterward. She has remained well on this MPA regimen for 45 months. The prognosis of patients with metastasizing leiomyosarcoma is poor because of its low sensitivity to chemotherapy; however, some types of leiomyosarcoma are hormone-sensitive. It is therefore important to examine the hormone receptors of excised tumors from patients suspected of having metastasizing leiomyoma or leimyosarcoma.

Antineoplastic Agents, Hormonal↗
PubMed1996

Primary linitis plastica of the rectum: report of four cases and review of the literature.

Primary linitis plastica of the rectum is a rare form of large bowel carcinoma, with only 30 cases having been reported in the English literature to date. Of significance is the fact that it carries a prognosis that is poor compared to other types of colorectal cancers. We report herein the cases of four patients with primary linitis plastica of the rectum who underwent surgery, followed by intensive postoperative chemotherapy using 5-fluorouracil (5-FU) derivatives in our institution. A review of the literature is presented with special reference to the diverse treatment and prognosis of this unusual disease. Although three of the patients died of recurrent cancer, one has survived for 5 years and 10 months despite advanced disease. This is only the third reported case of a patient with linitis plastica of the rectum achieving 5-year survival. We believe that this unexpected long survival could be related to the patient's extensive lymphadenectomy and intensive postoperative chemotherapy using cisplatin and 5-FU derivatives.

Aged↗
PubMed1996

Preoperative embolization of gastric arteries for esophageal cancer.

BACKGROUND: We developed a novel treatment of preoperative embolization therapy in an attempt to prevent anastomotic leakage after esophageal resection. We report the results of this new treatment. METHODS: Preoperative embolization therapy (PET) was performed in 24 cases of esophageal carcinoma. The femoral artery was punctured, and celiac angiography was performed. The left gastric artery and splenic artery underwent embolization. The right gastric artery then underwent embolization at a site beyond the second or third branch to the gastric wall. With a laser flow meter the stomach tissue blood flow was measured before and after construction of the gastric tube, and the change in blood flow was compared. RESULTS: The average decrease in gastric blood flow was 23% in patients with PET and 65% in patients without PET. Twenty-one (88%) of 24 cases maintained more than 50% tissue blood flow in patients with PET and in 1 (8%) of 12 in patients without PET (p < 0.001 by t test). No serious complications occurred. CONCLUSIONS: Preoperative embolization therapy is a safe and uncomplicated technique, and tissue blood flow in the stomach was better preserved. This new technique is expected to reduce the frequency of anastomotic leakage after esophageal operation.

Adult↗
PubMed1996

Association between preoperative plasma CEA levels and the prognosis of gastric cancer following curative resection. Tumor Marker Committee, Japanese Foundation for Multidisciplinary Treatment of Cancer, Tokyo, Japan.

A large-scale retrospective study was undertaken to evaluate the association between preoperative plasma carcinoembryonic antigen (CEA) levels and the prognosis of 2768 gastric cancer patients who underwent curative gastrectomy between 1983 and 1984 at 66 leading medical institutions in Japan Postoperative follow-up was at least 5 years. Preoperative plasma CEA levels were also analysed against other prognostic factors. Preoperative plasma CEA levels showed strong correlations to the degree of lymph node metastasis (P < 0.001), TNM stage (P = 0.004) and the histopathology of the gastric cancer (P < 0.001). Preoperative CEA levels were also evaluated against survival, after being adjusted for the effect of clinically important factors by multivariate analysis. Patients with lower preoperative plasma CEA levels survived significantly longer than patients with higher CEA levels (P = 0.0001). This analysis demonstrates that curatively resected gastric cancer patients with higher preoperative plasma CEA levels have a poorer prognosis than those with lower levels, despite the adjustment for the effects of major prognostic factors.

Adolescent↗
PubMed1996

Comparison of resistant starch with cellulose diet on 1,2-dimethylhydrazine-induced colonic carcinogenesis in rats.

BACKGROUND & AIMS: Epidemiological and experimental studies have shown that dietary fiber may prevent colon cancer. Resistant starch, like dietary fiber, is not subject to digestion in the small intestine. However, it is unknown whether resistant starch inhibits colonic carcinogenesis. In vitro studies have shown that butyrate slows the growth of cultured colon cancer cells. The effect of resistant starch diet on 1,2-dimethylhydrazine-induced colonic carcinogenesis in rats was evaluated, and the colonic butyrate concentration was measured. METHODS: Sprague-Dawley rats were randomly divided into five groups that were fed diets containing no fiber, 3% cellulose, 10% cellulose, 3% resistant starch, or 10% resistant starch. Colonic carcinogenesis and butyrate concentration of colonic contents and feces in each diet group were compared. RESULTS: Total cancer volume per rat in the 10% cellulose group was significantly lower than that in the basal group (109 +/- 54 mm3 and 247 +/- 83 mm3; P < 0.05), but the other groups showed no significant differences. The butyrate concentration in colonic content and in feces were higher in the resistant starch groups than in the cellulose groups. CONCLUSIONS: The resistant starch diet increased butyrate concentration but did not inhibit colonic carcinogenesis. It remains doubtful whether butyrate inhibits the proliferation of colon cancer cells.

1,2-Dimethylhydrazine↗
PubMed1996

Intra- and inter-complex cross-linking of subunits in the quinol oxidase super-complex from thermophilic Bacillus PS3.

Gram-positive thermophilic Bacilli contain quinol-cytochrome c reductase and cytochrome c oxidase as two major respiratory complexes of the electron transfer chain, and these enzymes can be extracted with mild detergents as an associated quinol oxidase super-complex. The reductase is composed of three subunits; cytochrome b6, cytochrome c1, and FeS protein, whereas cytochrome c oxidase consists of four subunits numbered 1 through 4. In order to clarify the interactions between the subunits, the super-complex isolated from Bacillus PS3 was cross-linked with three bifunctional cross-linkers; disuccinimidyl tartrate, 3,3'-dithiobis(succinimidylpropionate), and ethylene glycolbis(sulfosuccinimidylsuccinate). The most prominent cross-linking was observed for the combination of subunit 1 plus 2 in cytochrome c oxidase, and for that of cytochrome b6 plus cytochrome c1 in the reductase. In addition to these intra-complex cross-linkings, inter-complex linking was observed for the combination of cytochrome b6 plus subunit 1 with ethylene glycolbis(sulfosuccinimidylsuccinate), and for the combinations of cytochrome b6 plus subunit 1 and cytochrome b6 plus subunit 2 with 3,3'-dithiobis(succinimidylpropionate). Incubation in the presence of Triton X-100, which was confirmed to cleave the two enzyme complexes, selectively reduced the inter-complex cross-linking, suggesting that the chemical cross-linking reflect the spatial arrangement of subunits in the super-complex.

Bacillus↗
PubMed1996

Identification of peptide fragments chemically cross-linked in cytochrome c oxidase from thermophilic Bacillus PS3.

In order to study steric arrangement of subunits in cytochrome c oxidase isolated from thermophilic Bacillus PS3, we developed a simple procedure including chemical cross-linking, two consecutive runs of electrophoresis, proteolytic digestion, and peptide sequencing for simultaneous identification of two cross-linked fragments. By this procedure, the cytochrome c domain of subunit 2 was found cross-linked to C-terminal region of subunit 1 including two hydrophobic transmembrane segments, suggesting that these two regions were located close each other. The present simple procedure might be applicable to proteins whose crystal structures are not revealed.

Amino Acid Sequence↗
PubMed1996

[Administration of oral etoposide for one year as adjuvant chemotherapy for non-small cell lung cancer-side effect].

The possibility of using etoposide 25 mg daily as adjuvant chemotherapy for non-small cell lung cancer was discussed. Initially, 73 patients who had undergone resection participated in this trial; 49 of them were eligible, 24 including a patient over 70 years of age (8) took the drug for 1 year, 22 patients resigned from the study due to side effects, and a further 3 patients died during the trial. The main side effects observed were gastro-intestinal trouble (13) and pneumonia (4). The side effects of this drug appeared early in the treatment phase. During the first month of treatment, 9 patients discontinued the drug due to side effects, and 10 more did so within 4 months. To achieve optimal conditions for the trial study of low-dose etoposide it was found important to select patients under 70 years of age and to control side effects of the drug on the gastro-intestinal tract from the beginning.

Administration, Oral↗