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Biomedical subjects

T Kohno

Publications and source records attributed to T Kohno.

At least 397 records · Page 22Linked to original sources
PubMed1986

A highly sensitive enzyme immunoassay of anti-insulin antibodies in guinea pig serum.

A highly sensitive enzyme immunoassay of anti-insulin antibodies in guinea pig serum is described. Guinea pig anti-insulin serum was diluted to various extents with nonspecific guinea pig serum and incubated with insulin. After incubation, free insulin was separated from insulin-anti-insulin antibody complex by treatment with dextran-charcoal. Anti-insulin antibodies in the complex were dissociated from insulin by incubation with 0.23 M HCl and inactivated. The amount of dissociated insulin was measured by sandwich enzyme immunoassay using anti-insulin IgG-coated polystyrene balls and affinity-purified anti-insulin Fab'-horseradish peroxidase conjugate. The detection limit of anti-insulin antibodies in guinea pig serum was 6.7 pg/assay or 150 ng/liter of serum. The present enzyme immunoassay was 10,000-fold more sensitive than the previously described enzyme immunoassay, in which insulin-coated polystyrene balls were incubated with diluted guinea pig anti-insulin serum and subsequently with rabbit (anti-guinea pig IgG) Fab'-horseradish peroxidase conjugate.

Animals↗
PubMed1986

An autopsied case of acute hemorrhagic leukoencephalitis.

This is a clinico-pathological study of one case of acute hemorrhagic leukoencephalitis occurring in a patient with lung cancer. The main changes observed by light microscopy were in the white matter. All of these changes were the result of hemorrhage and demyelination around the venous vessels. Glial mesenchymal reactions were minimal. In view of these findings, this case supports the hypothesis that immune mechanisms play a role in the pathogenesis of neuropsychiatric symptoms during malignant illnesses. Here we will discuss the problem of differential diagnoses of acute hemorrhagic leukoencephalitis and its close morphologic similarities to perivenous encephalitis. Acute hemorrhagic leukoencephalitis and perivenous encephalitis may be a single entity of a demyelinating disease.

Acute Disease↗
PubMed1986

Down's syndrome associated with seminoma.

A case of unilateral seminoma in Down's syndrome is reported. The relation of testicular cancer with Down's syndrome and the necessity of the follow-up biopsy of the contralateral testis are discussed.

Adult↗
PubMed1986

Cerebral venous thrombosis due to high-altitude polycythemia. Case report.

A case of cerebral venous thrombosis due to polycythemia secondary to adaptation to a high altitude is reported. A 27-year-old previously healthy man developed severe neurological symptoms after climbing 8511 m. Computerized tomography and cerebral angiography suggested hemorrhagic infarction or intratumoral hemorrhage, and a craniotomy was performed. Pathological examination confirmed the diagnosis of hemorrhagic infarction secondary to cortical venous thrombosis. The etiology and incidence of cerebral venous thrombosis secondary to polycythemia are discussed.

Adult↗
PubMed1986

The state of the art on the chemical characterization of diesel particulates in Japan.

In this paper, the state of the art of the chemical characterization of diesel particulates in Japan is presented. However, some of these results are only preliminary. The principal contents may be summarized as follows: Characterization of Diesel Particulates; Examples of the application of the chemical characterization to various studies are described. Measurements for elemental composition and distributions of molecular weight and boiling point of diesel particulates and related samples were carried out to gain a better understanding of the main components of diesel particulates. Determinations of carbonaceous components, elemental carbon and organic carbon, in diesel particulates were made by a thermal carbon analyzer, and these results were applied to the study of the relations between such components and the driving conditions of diesel vehicles and to the estimate of emission rates of carbonaceous components from on-road diesel vehicles in a highway tunnel. It seems that the thermal carbon analyzer can be used to advantage in the determination of such carbonaceous components. Artifacts of PAH and 1-NP during Collection of Diesel Particulates; In order to minimize the artifacts of PAH during collection of diesel particulates, three methods were investigated for the artifacts of BkF, BaP and BghiP; two methods incorporated the removal of reactive gaseous components such as NO2, with an ACF method and an impinger method, and the third was a high dilution sampling method. These results suggest that the high dilution sampling method is very promising. From the results of various studies including model experiments, it is clear that the artifact formation of 1-NP is of first order dependence on total amounts of nitrate on carbon black and diesel particulates, not on gaseous nitric acid, although second order dependence of the artifact formation on NO2 concentration is ambiguous. Aside from the above studies, the relation between 1-NP concentrations in diesel exhaust and NO2 concentrations in the dilution tunnel with changing the dilution ratio at a fixed driving condition was utilized for an estimate of the artifact formation of 1-NP, and the estimated results are discussed in connection with the reaction order of the artifact formation on NO2 concentration. Concentrations of Various Components in Diesel Exhaust and Ambient Air; Analytical results are presented for the PAH, mononitro-PAH and dinitro-PAH in particulate samples collected from the exhaust of both IDI and DI diesel vehicles and the ambient air in several areas in Japan and China.(ABSTRACT TRUNCATED AT 400 WORDS)

Air↗
PubMed1985

Fibronectin of the chorioretinal interface in the monkey: immunohistochemical and immunoelectron microscopic studies.

The distribution of fibronectin in the chorioretinal interface of the monkey eye was studied by indirect immunofluorescent and immunoelectron microscopic techniques. Immunofluorescent staining revealed fibronectin in Bruch's membrane and the choriocapillaris. Immunoelectron microscopic techniques revealed fibronectin associated with basement membranes, collagen fibers and elastic fibers in Bruch's membrane; the stromal side of the basement membrane of the choriocapillaris also showed staining. This study thus demonstrates that fibronectin is an integral component of Bruch's membrane in the monkey eye.

Animals↗
PubMed1985

Purification and properties of beef liver aldehyde reductase catalyzing the reduction of D-erythrose 4-phosphate.

An aldehyde reductase catalyzing the NADPH-dependent reduction of D-erythrose 4-phosphate to D-erythritol 4-phosphate was purified from beef liver. It was proved to be homogeneous by polyacrylamide gel electrophoresis, sodium dodecyl sulfate polyacrylamide gel electrophoresis and ultracentrifugation analysis. The enzyme was proved to be a monomeric enzyme and its molecular weight was about 40,000. The enzyme was able to reduce not only tetroses but also trioses, aromatic aldehydes, D-glucuronate and succinic semialdehyde. Apparent Km-values for aromatic aldehydes were lower than those for tetroses, trioses, D-glucuronate and succinic semi-aldehyde. Barbiturates and valproate were potent inhibitors of the enzyme and their apparent K1-values were in the range of 80-180 microM. Quercitrin was the most potent inhibitor and its K1-value was about 7 microM. From the viewpoint of substrate specificity and inhibitor sensitivity, it seems that the enzyme belongs to the high-Km type aldehyde reductases.

Alcohol Oxidoreductases↗
PubMed1985

A more sensitive enzyme immunoassay of anti-insulin IgG in guinea pig serum with less non-specific binding of normal guinea pig IgG.

An enzyme immunoassay of anti-insulin IgG in guinea pig serum was improved in sensitivity by reducing the non-specific binding of normal guinea pig IgG and enhancing the specific binding of anti-insulin IgG. Silicone rubber pieces or polystyrene balls were coated with normal rabbit IgG, followed by coupling of insulin using glutaraldehyde. The insulin-normal rabbit IgG-coated silicone rubber pieces or polystyrene balls were incubated with normal rabbit IgG and then with diluted guinea pig anti-insulin serum in the presence of normal rabbit IgG at a lower temperature (20 degrees C). Finally, the solid phases were incubated with rabbit (anti-guinea pig IgG) Fab'-horseradish peroxidase conjugate to measure the amount of guinea pig IgG bound. The detection limit of anti-insulin IgG in guinea pig serum was improved 10 to 100-fold compared to that of enzyme immunoassay performed by incubating insulin-bovine serum albumin-coated solid phases with diluted guinea pig anti-insulin serum at 37 degrees C and then with rabbit (anti-guinea pig IgG) Fab' conjugated to beta-D-galactosidase from Escherichia coli, according to a previous report (Kato, K., et al. (1978) J. Biochem. 84, 93-102).

Animals↗
PubMed1985

A micro-scale method for the conjugation of affinity-purified Fab' to beta-D-galactosidase from Escherichia coli.

A micro-scale method for the conjugation of affinity-purified Fab' to beta-D-galactosidase from Escherichia coli is described. Rabbit anti-human chorionic gonadotropin serum (0.2 ml) was digested with pepsin to convert IgG to F(ab')2 and applied to a column of human chorionic gonadotropin-Sepharose 4B, followed by elution at pH 2.5. The affinity-purified anti-human chorionic gonadotropin F(ab')2 was mixed with non-specific goat F(ab')2 (0.5 mg) as a carrier, reduced with 2-mercaptoethylamine to split F(ab')2 to Fab' and conjugated to beta-D-galactosidase using N,N'-o-phenylenedimaleimide. The affinity-purified rabbit anti-human chorionic gonadotropin Fab'-beta-D-galactosidase conjugate was separated from non-specific goat Fab'-beta-D-galactosidase conjugate and unconjugated beta-D-galactosidase by affinity chromatography on a column of goat (anti-rabbit IgG) IgG-Sepharose 4B using 4 M urea. The amount of the affinity-purified conjugate obtained was 56-69 micrograms. The detection limit of human chorionic gonadotropin by a sandwich enzyme immunoassay technique was improved 30-fold by using the affinity-purified conjugate as compared with that before affinity-purification. This method is applicable to the conjugation with alkaline phosphatase from calf intestine and probably also other enzymes which are stable in 4 M urea.

Animals↗
PubMed1985

[Metastatic intracerebral malignant fibrous histiocytoma from the lung].

Malignant fibrous histiocytoma usually develops in the extremities, peritoneal or retroperitoneal space and the thigh. The occurrence in the lung and brain is quite rare. We report two cases of metastatic intracerebral malignant fibrous histiocytoma from the lung. The first patient developed cerebral metastasis six years after treatment of the primary site, and the second one died two months after the diagnosis of generalized metastases. Both were quite resistant to radiation therapy.

Brain↗
PubMed1985

[Effects of anticancer drugs on multicellular spheroid of 9L rat brain tumor].

The effects of the anticancer drugs Nimustine (ACNU), Aclacinomycin A (ACR), Adriamycin (ADM), Bleomycin (BLM), Cisplatin (CDDP), and 5-Fluorouracil (5-FU) on the multicellular spheroid of a chemically-induced 9L rat glioma was studied. The multicellular spheroid in which cells grow in vitro as three-dimensional aggregates represents a biological model, which is intermediate between monolayer cells in vitro and solid tumors. Spheroids were initiated in bacteriological grade petri dishes seeded with 10(6) 9L rat glioma cells, cultured for four days and thereafter transferred and further developed in a spinner flask. Spheroids of 200-400 micron diameter were sorted and exposed for 24 hours to 5-FU and one hour for other drugs. After treatment both cytotoxic effect and growth delay were analyzed. Following disaggregation using collagenase, pronase and DNAase, cytotoxic effect on multicellular spheroids was measured by colony forming assay and were compared with those effects on 9L monolayer culture cells in the exponential growth. For growth delay assay, multicellular spheroids were individually transferred to 16 mm well containing 0.4 ml agarose base and 2 ml culture medium. Spheroid size was measured twice a week and growth curves were drawn. The growth delay was determined as the treated group vs. control differences in time required to a size four times that of the initial volume. For cells both in the monolayer culture and the multicellular spheroid, the dose response curve for ADM, BLM and 5-FU was "biphasic" and that for ACNU, ACR and CDDP "shoulder-threshold" type.(ABSTRACT TRUNCATED AT 250 WORDS)

Aclarubicin↗
PubMed1985

Separation of hemolytic substances from anticancer preparations of hemolytic streptococci.

Preparations 60F and 50F isolated from the cell-free extract of anticancer hemolytic streptococci possessed not only anticancer activity but hemolytic activity. Thus, the experiment to separate hemolytic substances from 60F and 50F were carried out. Three kinds of fractions were obtained from 60F or 50F by dissolving them in ammonium sulfate solutions of various concentrations. These fractions were named 60F-I, 60F-II and 60F-III, and 50F-I, 50F-II and 50F-III, respectively. 60F-I and 50F-I possessed neither anticancer activity nor hemolytic activity. 60F-II and 50F-II possessed only anticancer activity, and 60F-III and 50F-III possessed only hemolytic activity. Thus, hemolytic substances were separated from 60F and 50F, and it was demonstrated that the anticancer activity of hemolytic streptococci was not due to their hemolysins or hemolytic activity.

Ammonium Sulfate↗