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Biomedical subjects

Y Oku

Publications and source records attributed to Y Oku.

At least 145 records · Page 8Linked to original sources
PubMed1989

Rapid growth of a meningioma during pregnancy: relationship with estrogen and progesterone receptors--case report.

Meningiomas are often described as hormone-dependent because of their preponderance in females and their tendency to clinically manifest during or after pregnancy. We describe a case of meningioma that grew rapidly during two pregnancies over a 2-year period. The tumor's rapid growth was confirmed by high-resolution computed tomography. Its estimated doubling time was 110 days. The tumor was removed and found to be a benign meningothelial meningioma. The tumor tissue was positive for estrogen receptors (ERs) and progesterone receptors (PRs). In nine cases, including this one, in which ERs and PRs were measured, the positive rate was much higher for PRs than for ERs; only two were positive for ERs. In the case reported here, it is presumed that the growth of the meningioma was influenced by estrogen and/or progesterone binding to receptors, although it is unclear whether one or both hormones was involved.

Adult↗
PubMed1989

[Limitation of RI imaging in evaluating lung function test--development of new methods].

We developed two methods for determining the regional distribution of (1) RV/TLC and air trapping during forced expiration and (2) the ratio or pulmonary blood volume to blood flow. 1) The regional distributions of RV/TLC and air trapping ratio: A.T.R. (air trapping caused by forced expiration) were measured in respiratory disease cases and normal subjects using Xe-133 gas. In normal subjects, RV/TLC gradually decreased from the apex to the base of the lung. A.T.R. was very low in all lung fields. In chronic emphysema (CPE), both RV/TLC and A.T.R. were much higher than the value in normal subjects at the highly diseased areas. In contrast, in case of diffuse panbronchiolitis (DPB), RV/TLC remained within the normal range and A.T.R. was increased considerably in the diseased regions. These results suggest that airway obstruction occurs only during the forced expiration in DPB. 2) The regional distribution of the ratio of pulmonary blood volume to blood flow (tau p) were measured in a normal subject and a case of mitral regurgitation. In both subjects, the distribution of 1/tau p consisted of three zones: upper, middle and lower. The distribution of 1/tau p was constant in the middle zone, but, in the upper and lower zones, it decreased in proportion to the distance from the middle zone. In the case of mitral regurgitation, the middle zone shifted to the apex. Applying the results to the lung perfusion model proposed by West, it was suggested that these phenomena might reflect the increase of the pulmonary venous pressure and the perfusion disorder in the lower lung.

Blood Volume↗
PubMed1989

[Evaluation of respiratory disability in patients of respiratory diseases using relationships between ventilatory drive, ventilation and thoracic pump function during exercise].

We studied the parameters of breathing control during exercise in patients with respiratory diseases for the evaluation of respiratory disability. The ventilatory drive during the same load exercise was increased in patients with respiratory diseases compared with that in normal subjects. In addition, the ratio of ventilation to ventilatory drive during exercise was decreased in patients with respiratory diseases. Impairment of rapid thoracic movement was suggested to be one of the mechanical limitations for ventilation in these patients, based on the findings of smaller esophageal pressure fluctuation during maximum ventilation of 40 respirations per minute than that in normal subjects. Flow at 0.1 sec after initiation of inspiration was designated V0.1. The increase of the ratio of V0.1 at rest to that at maximum voluntary inspiration (V0.0 (rest)/V0.1 (max)) indicate the grade of respiratory disability showing the impossibility of rapid movement of thorax as a parameter of thoracic pump function. It was recognized that the decrease of VE/P0.1 during incremental exercise indicated ventilatory insufficiency.

Exercise Test↗
PubMed1988

Development of a highly sensitive bead-ELISA to detect bacterial protein toxins.

A highly sensitive sandwich enzyme-linked immunosorbent assay to detect bacterial toxins was developed. Fab' of anti-toxin IgG was conjugated with horseradish peroxidase by the maleimide method and tetramethylbenzidine was used as substrate. As the solid phase, a 6.5 mm diameter polystyrene bead was used and this was coated with the anti-toxin IgG. The entire assay could be completed within 3.5 hr. The sensitivity of this bead-ELISA was found to be quite high with various bacterial toxins: less than 20 pg/ml for thermostable direct hemolysin of Vibrio parahaemolyticus, less than 60 pg/ml for Shiga toxin, less than 20 pg/ml for VT2 (Shiga-like toxin II) of Escherichia coli, less than 200 pg/ml for heat-labile enterotoxin of E. coli, and less than 6 pg/ml for cholera enterotoxin.

Bacterial Proteins↗
PubMed1988

Immunoelectron microscopic studies on spore coat proteins of Bacillus megaterium.

An immunochemical staining technique for the spore coat proteins of Bacillus megaterium ATCC 12872 was developed using colloidal gold as a second antibody. For reducing the non-specific immunogold binding and increasing the specific binding, the affinity-purified IgG was used as a first antibody. In sporulating cells at t10, gold particles were found not only in the spore coat but also in the mother cell cytoplasm, suggesting that some coat proteins were synthesized in the cytoplasm. Use of the specific affinity-purified antibody to 48K-protein demonstrated that this protein was one of the components of the outer coat.

Bacillus megaterium↗
PubMed1988

Toxin profiles of Vibrio cholerae non-O1 from environmental sources in Calcutta, India.

A collection of Vibrio cholerae non-O1 isolated from the aquatic environs of Calcutta, a cholera-hyperendemic area, were examined for the production of cholera toxin (CT), Shiga-like toxins (Vero toxins), heat-stable enterotoxin, and hemolysins. Two (0.5%) V. cholerae non-O1 isolates produced CT. The DNA from both these isolates also hybridized with a DNA probe containing sequences encoding the A subunit of CT. None of the strains produced Shiga-like toxins or heat-stable enterotoxin. Hemolytic activity was observed in 89.7% of the strains, of which 36.1% exhibited biological activity in the suckling mouse. However, none of them produced a hemolysin that cross-reacted with the thermostable direct hemolysin of Vibrio parahaemolyticus. It appears from this study that a small percentage of environmental V. cholerae non-O1 strains do possess the potential for causing cholera-like diarrhea.

Cholera↗
PubMed1988

[Effect of ACNU against experimental brain tumor--immunohistochemical study using anti-BrdU monoclonal antibody].

We have studied the efficacy of intrathecal ACNU against experimental leptomeningeal tumors. In the present report, the effect of ACNU on the growth kinetics of the tumor was evaluated by the immunohistochemical technique using anti-BrdU monoclonal antibody. The experimental leptomeningeal tumor was developed by inoculation of Walker 256 carcinosarcoma cells into the cisterna magna of rats. Seven days after the inoculation of tumor cells, the animals were treated either by intravenous (15 mg/kg) or intrathecal (1.5 mg/kg) ACNU. Four, 12, 24, 48, 96 or 144 hours after treatment, the animals received intravenous BrdU (200 mg/kg). Thirty minutes thereafter, they were sacrificed and the brain was removed. L. I. was calculated by counting the immunoreactive tumor cells. L. I. of the tumor without treatment on the seventh day after inoculation was over 40%. L. I. began to decrease 24 hours after intravenous ACNU, and remained 11% up to 96 hours. On the other hand, L. I. already decreased to 20% 4 hours after intrathecal ACNU and remained to be low (17%) up to 48 hours. However, L. I. increased to 38% at 96 hours. Thus, the effect on the growth kinetics of the tumor differs between intravenous and intrathecal ACNU. These results are considered to be useful informations for determining the optimal dosage of the antineoplastic agent against the brain tumor and developing the effective combination chemotherapy.

Animals↗
PubMed1988

[Effect of MX-2, a morpholino anthracycline derivative, against human and rat glioma cells and experimental leptomeningeal tumors in rats].

MX-2, a new morpholino anthracycline derivative, showed broad anti-neoplastic activity against experimental tumors. Molecular weight of MX-2 is 622.07, and it can cross blood-brain barrier because of its high lipid solubility. In this report, we described its in vitro and in vivo effects on brain tumors. The growth of rat 9L and human KNS-42 glioma cells were markedly inhibited by the medium containing more than 1 ng/ml of MX-2. The inhibitory concentration of MX-2 for 50% cell kill was 1.8 ng/ml for 9L cell and 18 ng/ml for KNS-42, respectively. These values were the almost same as those reported with P388 leukemia. In rats with meningeal carcinomatosis induced by intracisternal inoculation of Walker 256 carcinosarcoma cells, the median survival time was significantly prolonged. The increased life span was 40, 40, 40 (p less than 0.01), and 20% (p less than 0.05) in the animals given intravenous MX-2 of 1.5, 1.0, 0.75, and 0.375 mg/kg on day 1, 5, and 9 after tumor inoculation respectively. These results indicate that MX-2 may be a promising new antineoplastic agent for the treatment of malignant brain tumor.

Animals↗
PubMed1987

Comparative antigenicity of spore coat proteins from Bacillus species using antibody to spore coat proteins of Bacillus megaterium.

Spore coat proteins obtained by extraction with sodium dodecylsulfate/dithiothreitol from six Bacillus spores were compared by immunoblot analysis using antibodies to spore coat proteins from two strains of B. megaterium. Although the extract from spores of each strain had heterogenous proteins with various molecular weights, there were some bands which cross-reacted with specific antibodies from B. megaterium spores. Specific antibody to 48K protein from B. megaterium ATCC 12872 cross-reacted with 17K protein from B. megaterium ATCC 19213, 13K protein from B. cereus and 50K protein from B. subtilis 60015 and B. subtilis NRRL B558. Also, specific antibody to 22K protein from the same strain cross-reacted with 22K and 17K proteins from B. megaterium ATCC 19213 and 13K protein from B. cereus T. Specific antibody to 17K protein from B. megaterium ATCC 19213 reacted with 22K and 19K proteins in addition to 17K protein of own strain, and it was cross-reactive with 16K protein from B. megaterium ATCC 12872, 19K and 27K proteins from B. thiaminolyticus, 13K protein from B. cereus.

Antibodies, Bacterial↗
PubMed1987

[Hyperprolactinemia in patients with non-functioning adenoma: analysis of 85 patients treated by transsphenoidal operation].

Today, many gynecologists consider that the first choice of the treatment of prolactinomas is bromocriptine therapy. Because bromocriptine not only decreases the levels of serum prolactin but also reduces the tumor size. On the other hand, the patients with non-functioning adenoma sometimes show hyperprolactinemia, probably because PIF (prolactin inhibiting factor) cannot reach the normal prolactin-producing cells of the adenohypophysis. Therefore non-functioning adenoma with elevated serum prolactin levels should be distinguished from prolactinoma. Eighty five patients with non-functioning adenoma were treated with transsphenoidal operation at Hiroshima University Hospital, and Kansai Rosai Hospital from May, 1978 to March, 1981 and at Osaka University Hospital, The Center for Adult Diseases, and Kansai Rosai Hospital from April, 1981 to May, 1986. Non-functioning adenomas were diagnosed by clinical feature, endocrinologic examination, and immunohistochemical study. There were 42 male and 43 female patients, whose age ranged from 17 to 76 years (mean: 49). The most frequent chief complaint was visual disturbance (86%). Amenorrhea-galactorrhea was complained by 9 female patients. However, 7 of them had visual disturbance at the same time. Hyperprolactinemia was seen in 21 patients (30%). The highest serum level of prolactin was 163.2 ng/ml. All of the patients had macroadenomas. There were 2 invasive adenomas and 83 expensive adenomas in them. After operation, cure or improvement of the visual disturbance was noted in almost all the patients. The serum levels of prolactin were normalized in 16 of 17 hyperprolactinemic patients. In conclusion, transsphenoidal operation is the best treatment of non-functioning adenomas. However, it is difficult to decide before operation whether the macroadenoma with serum prolactin level between 100 and 200 ng/ml is non-functioning adenoma or prolactinoma.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma↗