Search PubMed⌕ Search

Biomedical subjects

M Ohta

Publications and source records attributed to M Ohta.

At least 1,081 records · Page 60Linked to original sources
PubMed1986

[Effect of immunotherapy using the non-specific immunopotentiator OK-432 in malignant ovarian tumors--selecting appropriate cases for immunotherapy].

Immunotherapy for malignant ovarian tumors has been discussed in a number of recent studies. However, the effects of this therapy are produced by an indirect mechanism, and are, therefore, difficult to evaluated. In order to select appropriate cases for immunotherapy using OK-432 against malignant ovarian tumors, clinical and experimental studies were carried out. Clinically patients with ovarian cancer were divided into two groups; OK-432 treated group and no immunotherapy groups. As a parameter of immunoresponse to OK-432, PHA and Su-PS skin tests were performed periodically. Natural killer (NK) cell activity was also measured before and after administration of OK-432. Peripheral blood lymphocyte subsets were analysed by using monoclonal antibody and a laser flow cytometer. Finally tumor growth velocity was evaluated in tumor transplanted nude mice. The survival rate was used as an index for evaluation. The survival rate of the OK-432 treated groups was better than the control groups in advanced cases, but a statistically significant difference was found between the two groups. Among fundamental studies which were carried out to select appropriate cases, Su-PS skin test, the NK response of OK-432 seemed to be actually utilized.

Animals↗
PubMed1986

Prognostic significance of nuclear analysis in invasive carcinoma of cervix patients treated by primary radiation.

The value of microspectrophotometric analysis was studied for the assessment of prognosis in patients with squamous cell carcinoma of the cervix treated with primary radiation therapy. Cellular nuclear desoxyribonucleic acid (DNA) content and nuclear size were measured in smears taken before, during and immediately after radiation therapy. Additional determination of DNA content/nuclear size ratio was made. Changing patterns of DNA distribution, nuclear size and their ratio were classified into Type I, II, III, and IV, according to the mode of their shifts in the course of radiation therapy. The results showed diploid (47%), polyploid (23%) and aneuploid (30%) DNA distribution in pre-treated carcinomas. Particularly, the results showed a distinct correlation between the type of histograms and patient outcome. Patients with Type II histograms (initial shift to the right and posterior shift to the left) showed a better survival rate and no recurrences compared with other types. On the other hand, patients with Type III histograms (initial shift to the left and posterior shift to the right) had poor prognosis and were predominant among dead cases with radioresistant tumors. These results suggested the potential usefulness of cytophotometric analysis for assessing prognosis in advanced cases.

Adult↗
PubMed1985

Increased anticonvulsant effect of phenobarbital with age in mice--a possible pharmacological index for brain aging.

We have recently reported that the anticonvulsant effect of phenytoin increases with age in mice (1). Since some of the mechanisms of anticonvulsant action of phenytoin and phenobarbital may be different, the present study sought to determine whether a similar increase with age in the anticonvulsant effect of phenobarbital could also be observed. The anticonvulsant effect of phenobarbital was examined in BDF1 female mice of different ages (6, 12, 24 and 30 months old) using the abolition of the tonic hindlimb extensor component of maximal electro-shock seizure as the index. The minimal effective concentration (MEC) values of phenobarbital in plasma and brain were significantly lower in aged (24 and 30 month old) mice compared with the respective values in the youngest animal group (6 month old). Series using nearly two-fold different intensities of electroshock (30 and 55 mA) showed almost identical MEC values in 24 month-old mice. It was concluded that the brain of aged mice is more sensitive to phenobarbital, as it is to phenytoin.

Aging↗
PubMed1985

1 alpha,25-Dihydroxyvitamin D3 (calcitriol) stimulates proliferation of human circulating monocytes in vitro.

Previous studies demonstrated that human circulating monocytes can proliferate in vitro when incubated with lectin-induced factor(s) from lymphocytes [(1985) Biochem. Biophys. Res. Commun., in press]. This study shows that human monocytes were induced to proliferate when incubated with 1 alpha,25-dihydroxyvitamin D3 (calcitriol) at physiological concentrations. The optimal dose was about 10 nM. Proliferative activity was examined both by measuring the [3H]thymidine incorporation and by counting cell nuclei. Among other derivatives of vitamin D3, 1 alpha,24R-dihydroxyvitamin D3 and 1 alpha,24R,25-trihydroxyvitamin D3 stimulated mitotic activity of monocytes. Addition of both calcitriol and lectin-stimulated lymphocyte-conditioned medium to the monocyte culture had an additional effect on the mitotic activity of monocytes.

Calcitriol↗
PubMed1985

Age related increased threshold for electroshock seizure in BDF1 mice.

The thresholds for inducing the minimal and maximal electroshock seizures were examined in relation to age in BDF1 mice of both sexes. The 50 percent effective intensities for the maximal electroshock seizure (tonic hindlimb extensor component) were lowest in the youngest age groups (6-month-old) for both male (10.68 mA) and female (9.18 mA) animals. The threshold increased with age and became significantly higher at 24 months (14.00 mA, 12.70 mA for male and female mice respectively). There was also a further increase in threshold at 30 months for both sexes. Similarly, the threshold for inducing the minimal seizure also increased with age but the differences in mean threshold levels between the youngest and oldest groups were much smaller in comparison to the maximal seizure. It was concluded that the threshold for inducing electroshock seizures significantly increases with age in mice of both sexes.

Age Factors↗
PubMed1985

Induction of proliferation of human circulating monocytes in vitro by lectin-induced factor(s) from lymphocytes.

Human peripheral blood monocytes, which have been considered to be non-dividing cells, were induced to proliferate in vitro by soluble mediator(s) from lectin-activated human lymphocytes. The lectin-induced factor from lymphocytes increased both the number of nuclei of cultured monocytes and [3H]-thymidine incorporation into the monocytes. The molecular weights of the soluble factor(s) that promote growth of monocytes were in the range of 20,000-70,000 daltons with two peaks.

Adult↗
PubMed1985

Cushing's disease: pituitary microadenoma demonstrated by high resolution computed tomography with thin slices.

A girl 16 7/12 years of age with Cushing's disease secondary to pituitary microadenoma is described. The tumor was very clearly demonstrated by high-resolution contrast-enhanced computed tomography (CT) with thin slices and was removed by transsphenoidal microadenomectomy. In some patients with Cushing's disease levels of ACTH and cortisol are not always high. Therefore, high-resolution contrast-enhanced CT with thin slices should be performed when the diagnosis of Cushing's disease is suspected even when the definite diagnosis cannot be established by endocrinological examinations.

Adenoma↗
PubMed1985

Congenital choledochal dilatation associated with carcinoma after choledochocystoduodenostomy--case report and a review of the literature.

A 24-year old Japanese woman with congenital choledochal dilatation associated with carcinoma, cholelithiasis and pancreatolithiasis was treated. She had undergone choledochocystoduodenostomy at the age of 5 years. At the present admission, a dilated choledochus was excised and hepaticojejunostomy (Roux-en-Y anastomosis) and pancreatic ductojejunostomy were performed. Adenocarcinoma involved the entire mucosal surface of the resected specimen. We also present a review of the literature on the treatment and prognosis of patients with congenital biliary dilatation associated with carcinoma after bypass operation in childhood. We emphasize that in patients with congenital choledochal dilatation, the dilated choledochus should be excised, even in young children.

Adult↗
PubMed1985

Inhibition by succinyl concanavalin A of strong adjuvant activity of lipopolysaccharides which possess mannans as the O-specific polysaccharide chains.

It has been reported that lipopolysaccharides (LPS) from Klebsiella O3 and O5 and Escherichia coli O8 and O9 exhibit extraordinarily strong adjuvant activity in augmenting antibody responses against protein antigens in mice as compared with other kinds of LPS. These four kinds of LPS all possess homopolysaccharides consisting of mannose (mannans) as the O-specific side chains. When these kinds of LPS were mixed in vitro with succinyl concanavalin A (Con A) which is known to bind specifically to alpha-mannoside and alpha-glucoside, their strong adjuvant activity was inhibited. Degree of the inhibition of the adjuvant activity of Klebsiella O3 LPS by succinyl Con A was dependent upon the dose of succinyl Con A. However, phytohemagglutinin, which is known to bind specifically to N-acetyl-D-galactosamine, did not inhibit the adjuvant activity of Klebsiella O3 LPS and O5 LPS. When Klebsiella O3 LPS was mixed with succinyl Con A in the presence of excess amounts of alpha-methyl mannoside or the polysaccharide fraction isolated from Klebsiella O3 LPS, the inhibitory effect of succinyl Con A on the adjuvant activity of Klebsiella O3 LPS was blocked. By contrast, the activity of Klebsiella O3 LPS as a polyclonal B-cell activator was not affected by treatment with succinyl Con A. From these results it is concluded that the mannans, as the O-specific polysaccharide chains of the LPS, significantly contribute to expression of their strong adjuvant activity.

Adjuvants, Immunologic↗
PubMed1985

Potent adjuvant action of lipopolysaccharides possessing the O-specific polysaccharide moieties consisting of mannans in antibody response against protein antigen.

It was previously reported that Klebsiella O3 lipopolysaccharide (LPS) exhibits extraordinarily strong adjuvant activity in augmenting antibody response against protein antigens in mice compared with other kinds of LPS, for example, LPS from Escherichia coli O55, O111, and O127 and Salmonella enteritidis. The present study was undertaken to clarify the relationship between the strong adjuvant activity in augmenting antibody response against deaggregated bovine gammaglobulin and the chemical structure of LPS. Among LPS from Klebsiella O1, O4, O5, and O7, only O5 LPS exhibited nearly the same degree of the strong adjuvant activity as did O3 LPS. The adjuvant activity of the other LPS was very weak in a degree similar to that of LPS from E. coli O55 and O127. Even when the natural forms of Klebsiella O3 LPS and O1 LPS were converted to various defined uniform salt forms, their adjuvant activity did not significantly differ from that of the respective natural forms. It is therefore unlikely that the difference in strength of the adjuvant activity between Klebsiella O3 LPS and O1 LPS is due to the difference in their salt forms. The common feature in the structures of Klebsiella O3 LPS and O5 LPS is their O-specific polysaccharide chains consisting of the mannose homopolysaccharides (mannans). LPS from E. coli O8 and O9, the O-specific polysaccharide chains of which consist of the mannans, also exhibited much stronger adjuvant activity than do LPS from E. coli O55 and O127, and the strength of the adjuvant activities of the former two was comparable to that of LPS from Klebsiella O3 and O5. On the other hand, LPS from Klebsiella O3 and O5 and E. coli O8 and O9 showed the ability to activate B lymphocytes polyclonally in vivo in a degree similar to that of the other kinds of LPS. From the present results it can be concluded that LPS possessing the O-specific polysaccharide moieties consisting of the mannans exhibit extraordinarily strong adjuvant activity in augmenting antibody response against protein antigen.

Adjuvants, Immunologic↗
PubMed1985

Mixed colloid cyst-xanthogranuloma of the third ventricle. A light and electron microscopic study.

A mixed colloid cyst-xanthogranuloma of the third ventricle is described. The xanthogranuloma associated with the cyst completely occupied the third ventricle. On light microscopy, a single epithelial layer with a basal lamina was seen lining the cyst wall. Electron microscopic study revealed three different kinds of cells in the epithelial layer: ciliated, nonciliated, and basal cells. Many lipid droplets were present in the superficial epithelial cells, macrophages, pericytes, and endothelia. The pathogeneses of the cyst and of the xanthogranuloma are discussed.

Brain Diseases↗