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Biomedical subjects

Y Ogata

Publications and source records attributed to Y Ogata.

At least 217 records · Page 12Linked to original sources
PubMed1989

[An integrated control system for radioisotope facilities].

The authors developed an integrated system for managing the safe use of radioisotope laboratory facilities, users' access to controlled areas, and the control of air-conditioners. This system consisted of a personal computer, an access controller, an eye retinal verifier, magnetic card readers, hand foot cloth monitors, video tape recorders and a fire alarm system. The access controller was set as the central unit to operate the whole system including 13 gates and air-conditioners. Under this program, only registered persons were permitted to enter the laboratories; the exact records on access were easily obtained; and electricity and fuel expenses were largely reduced. We expect that the system would facilitate the safe use of radioisotopes and the utilization of laboratory facilities.

Facility Design and Construction↗
PubMed1989

[Intra-arterial infusion chemotherapy of liver metastases in colorectal cancer].

We report the complications and the results of intra-arterial infusion chemotherapy (IAIC) for liver metastases in colorectal cancer. Fifteen synchronous liver metastases and 11 metachronous liver metastases were treated from September 1986 to February 1989. Eight cases had H1 (metastases in one lobe only), 11 cases H2 (a few scattered metastases in both lobes) and 7 cases had H3 (numerous metastases in both lobes). Eight cases underwent hepatic resection and 20 cases were treated by IAIC with implantable reservoir. Incidence of complication was decreased from 75% to 17% by the improved technique of hepatic arterial catheter intubation. Median survival was 12 months, 20 months and 8 months, respectively. When used with MMC, the IAIC showed unsatisfactory results. We should therefore investigate possible use of alternative drugs, their optimum dosages, and the regimens for improved chemotherapy.

Adult↗
PubMed1988

Purification, characterization, and biosynthesis of bovine enamelins.

Enamelins were extracted from developing bovine enamel with 0.5 M EDTA, 4 M guanidine HCl, and purified by DEAE-Sephacel, Sephacryl S-200, and high-performance gel filtration chromatography. Four distinct enamelins having molecular weights of 70, 45, 30, and 28 K daltons were isolated. Their amino acid compositions were found to be rich in Pro, Glu, Gly, and Asp. Low molecular weight enamelins (45, 30, and 28 K) were more abundant in Pro, Gly, and Phe. Two-dimensional electrophoretic pattern of enamelins revealed several spots that immunoreacted to monoclonal anti-enamelin antibody raised in mice. Enamelins were found to be comprised of heterogeneous proteins as well as amelogenins. Biosynthesis of enamelins was investigated by incubating the bovine ameloblast cell layer, and several radioactive enamelins were identified by the use of two-dimensional electrophoresis. The data in this study suggest that enamelins were synthesized by the ameloblasts.

Ameloblasts↗
PubMed1988

Bile acids are able to reduce blood pressure by attenuating the vascular reactivity in spontaneously hypertensive rats.

Effects of the synthetic bile acids on blood pressure were examined in spontaneously hypertensive rats. Continuous intravenous administration of the bile acids at the rate of 1 mg/min for 20 min significantly lowered the blood pressure by 12 mmHg. In order to examine its blood pressure lowering mechanism, the isolated mesenteric arterial perfusion system was employed. Bile acids in the perfusate inhibited vascular reactivity to norepinephrine and KCl in a dose-dependent manner. This inhibitory action diminished as the concentration of potassium in the perfusate decreased. When the perfusate was free from potassium, its inhibitory action completely disappeared. These results in vivo and in vitro studies strongly suggest that bile acids act directly on the vascular beds and attenuate vascular response to norepinephrine.

Animals↗
PubMed1988

Monitoring of 131I in milk and rain water in Japan following the reactor accident at Chernobyl and estimates of human thyroidal dose equivalents.

Iodine-131 in milk and in rain water in Nagoya, Japan, (a location 8,000 km from Chernobyl) was monitored between May and July 1986. The 131I concentration in rain water ranged from 43.1 Bq L-1 on 4 May to 15 mBq L-1 on 12 July, and that in milk ranged from 21.8 Bq L-1 on 19 May to 11 mBq L-1 on 14 July. Iodine-131 concentrations in milk were estimated to be 4 to 6 times greater than those in rain water during the first few weeks after the accident. Both concentrations decreased with approximately the same effective half-life of 5.9 +/- 0.3 d for rain water and 5.0 +/- 0.2 d for milk. The 131I concentration in milk sold in markets varied from dairy to dairy and ranged from 0.07 to 0.2 times that in fresh milk. The maximum thyroidal dose equivalents estimated for an adult man and for a baby were far lower than the population annual dose equivalent to the thyroid from natural radiation.

Accidents↗
PubMed1987

Epitopes on proliferating cell nuclear antigen recognized by human lupus autoantibody and murine monoclonal antibody.

The immune epitopes of proliferating cell nuclear antigen (PCNA), also called cyclin, were analyzed by determining the reactivity between PCNA peptide fragments and anti-PCNA antibodies from lupus patients, murine monoclonal antibody (19A2), and rabbit anti-NH2-terminal peptide antibody. Limited digestion of PCNA/cyclin with Staphylococcus aureus V8 protease resulted in several peptide fragments. Five fragments of 30, 20, 15, 14, and 13 kDa were reactive with rabbit anti-NH2-terminal peptide antibody denoting that they contained the NH2-terminal peptide. The 30- and 20-kDa fragments reacted with 19A2 but the others did not. Lupus sera reacted with 17- and 15-kDa peptide fragments allowing their classification into three groups. Two of eight sera (type A) reacted only with the 17-kDa fragment. Two others (type B) reacted with both the 17- and 15-kDa fragments and the remaining four sera (type C) reacted only with the 15-kDa fragment. The sera reacting with the 15-kDa fragment also reacted with the 20-kDa fragment, but the sera reactive only with the 17-kDa fragment did not, indicating that the 17-kDa fragment was not a degradation product of 20-kDa fragments. The 19A2 epitope resided in the region between 15 and 20 kDa from the NH2 terminus, whereas there was at least one distinct epitope on each 15- and 17-kDa peptide, which were recognized by lupus autoantibodies.

Animals↗
PubMed1987

The long-term survival of patients with carcinoma of the main hepatic duct junction.

Carcinoma of the main hepatic duct junction tends to invade extensively the bile ducts and hepatic parenchyma, although dissemination is rarely seen. Therefore, extensive resection of the bile ducts combined with hepatic resection is the procedure of choice for treating this disease. From January 1973 to January 1987, 23 of 41 patients underwent resection, giving a resectability rate of 56%. One patient died postoperatively, yielding an operative mortality rate of 4.3%. The 5-year actuarial survival rate is 29.8%. Three patients are now alive and well 6 years and 9 months, 5 years and 10 months, and 5 years and 5 months after the operation. One additional patient who underwent resection in an affiliated hospital has done well for 8 years and 8 months. The results from these four patients treated by curative resection support a strategy featuring curative resection with aggressive surgery.

Aged↗
PubMed1987

[Data processing system of personnel exposure with personal computer].

This paper describes a software package that manages personnel exposure data with a personal computer. The exposure data is automatically transferred to the computer through a floppy disk supplied by film badge service companies. The computer processes data of about 4000 persons who belong to the 11 facilities and prints out the reports on the distribution of personal exposure level. This system made it possible for the radiation protection division to rapidly investigate the actual situation of occupational exposure with less laborious works.

Air Pollution, Radioactive↗
PubMed1987

[Serological test of carbohydrate antigen CA50 in patients with cancer of the digestive tract].

In order to determine the clinical usefulness of carbohydrate antigen CA50 as a marker for cancers of the digestive tract, an attempt was carried out to measure the CA50 levels (normal level less than or equal to 18.1 U/ml) in sera of patients with various diseases of the digestive tract including pancreatic cancer. In patients with pancreatic cancer, the frequency of elevation of CA50 was 85.7% (6/35), which was the highest frequency of elevation, and a serum level of over 1,000 U/ml was observed in 6 (17.1%) of these 35 pancreatic cancer patients. Furthermore, patients with gall bladder carcinoma, hepatocellular carcinoma and gallstones showed relatively high frequencies of elevation. On the other hand, the maximum level of CA50 in serum was 41 U/ml in patients with benign pancreatic disease. Therefore, it was thought that CA50 was able to differentiate pancreatic cancer from benign pancreatic disease in patients with pancreatic disease with extremely high levels of CA50. The serum level of CA50 showed significant correlation with that of CA19-9. This study suggested that CA50 might be a potentially useful marker.

Antigens, Neoplasm↗
PubMed1986

Relationship of exercise or pacing induced ST segment depression and myocardial lactate metabolism in patients with hypertrophic cardiomyopathy.

To elucidate a mechanism and clinical implications of chest pain and ST segment depression during exercise in patients with hypertrophic cardiomyopathy (HCM), we investigated myocardial lactate metabolism during atrial pacing in 18 patients with HCM and 7 control subjects with normal coronary arteriograms. At an average peak pacing rate of 146 beats/min, 11 patients with HCM showed the lactate extraction ratio decreasing to less than 5%, and 6 of them produced lactate, suggesting the development of myocardial ischemia. These 11 patients with abnormal lactate metabolism demonstrated ST segment depression (82%) and chest pain (73%) during pacing and also presented abnormal results (55%) on an exercise stress test. These abnormal findings were not observed in the other 7 patients who had ratios of 5% or more at peak pacing. These observations suggest that ST segment depression and chest pain are manifestations of myocardial ischemia even in patients with HCM who have normal coronary arteriograms, and that patients with pacing induced abnormal lactate metabolism are at an increased risk of developing myocardial ischemia during exercise.

Adolescent↗
PubMed1986

[Detection of DU-PAN-2 antigen (pancreatic cancer-associated antigen) in sera of patients with cancer of the digestive tract].

DU-PAN-2 is an antigen detected by a monoclonal antibody to pancreatic adenocarcinoma. In order to determine the clinical usefulness of DU-PAN-2 for diagnosis and monitoring in cancer patients, the DU-PAN-2 level (EIA, less than or equal to 300 U/ml) was measured in 238 patients with cancer of the digestive tract including 47 with pancreatic cancer, and in 57 with benign abdominal disease. The positive rate and maximum level for pancreatic cancer were 48.9% and 85,960 U/ml, respectively. However, DU-PAN-2 levels were also relatively high in hepatobiliary cancers. For stage II pancreatic cancer, the positive rate and maximum level of DU-PAN-2 were only 22.2% and 661 U/ml, respectively. On the other hand, these values were 0% and 196 U/ml (pancreatic cyst) in 15 benign pancreatic diseases. In postoperative monitoring of up to 35 months in 17 resected patients with pancreatic cancer, the DU-PAN-2 level decreased on resection of the tumor and increased on recurrence. This study suggested that DU-PAN-2 seems promising as a means for differentiating pancreatic cancer from benign pancreatic disease and for detecting the recurrence of pancreatic cancer. However, differentiation between pancreatic and hepatobiliary cancers appears difficult.

Antigens, Neoplasm↗