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Biomedical subjects

T Furuta

Publications and source records attributed to T Furuta.

At least 379 records · Page 21Linked to original sources
PubMed1984

Selective effects of Lipiodolized antitumor agents.

Lipiodol Ultra-Fluid (Lipiodol) remains selectively in the tumor for an extended time when applied through arteries feeding the tumor. Although lipophilic antitumor drugs are selective when combined with Lipiodol, wide application of common hydrophilic agents is limited, as these compounds are insoluble in oil. We propose "Lipiodolization" of water-soluble agents using as an intermediate Urografin, a water-soluble contrast medium. Thirteen patients with primary hepatocellular carcinoma were treated with this Lipiodol-Urografin system containing antitumor agents. Marked decrease in serum alpha-fetoprotein (AFP) levels, decrease in tumor size in the hepatic imaging, and histologic studies of the resected specimen revealed this mode of therapy to be effective in 10 of 13 patients (77%) with hepatocellular carcinoma. Lipiodolization of antitumor agents is a new approach to selective cancer chemotherapy.

Adult↗
PubMed1984

3-(p-hydroxyphenyl)propionic acid as a new fluorogenic reagent for amine oxidase assays.

A detailed procedure of a new and extremely sensitive fluorometric assay for amine oxidases is presented. Hydrogen peroxide, produced by the oxidase reaction, reacted with 3-(p-hydroxyphenyl)propionic acid in the presence of peroxidase to yield a fluorescent compound by which enzyme activity could be determined. The enzyme reaction was terminated by NaOH solution, which increased the fluorescence intensity three- to fivefold. The detection limit thus obtained was as little as 0.02 nmol. The alkalinization also contributed to stopping the enzyme reaction and to the clarification of assay mixtures containing turbid enzyme preparations.

Amine Oxidase (Copper-Containing)↗
PubMed1984

Limited hepatic resection effective for selected cirrhotic patients with primary liver cancer.

We evaluated in retrospect the applicability of limited hepatic resection in cases of primary liver cancer in cirrhotic patients. According to the severity of impaired liver function, 37 patients underwent limited resection, and for 13, standard major hepatic resection was done. The mortality rate in case of limited resection was 10.8%, and the rate in case of massive excision was 15.4%. One, two- and five-year survival rates of limited operation were 79.9, 60.3, and 32.6%, respectively. After standard resection, the rates were 78.7, 67.5, and 22.5%, respectively. There were no significant differences in the mortality and survival rates between the two groups. These results indicate that, for the patient with a small liver cancer, and poor liver function, the limited procedure leads to a comparatively longer survival. This limited resection can be selectively used to treat cancer associated with cirrhosis and encapsulated tumors. For the preoperative evaluation, hepatic arteriograms aid in patient selection.

Adult↗
PubMed1984

Characterization of a monoclonal antibody specific for lipoteichoic acid from various gram-positive bacteria.

A hybrid cell line, 3G6, producing monoclonal antibody (mAb) against the polyglycerophosphate (PGP) backbone of lipoteichoic acids has been derived by the polyethylene glycol-induced fusion of mouse myeloma cells and spleen cells from mice immunized with partially purified glucosyltransferase from culture supernatant of Streptococcus mutans strain 6715. Immunodiffusion tests and ELISA revealed that the antibody reacted with purified PGP from group A Streptococcus pyogenes strain Sv as well as crude phenol-water and saline extracts of various gram-positive bacteria except for a few species such as biotype B S. sanguis, Micrococcus sp., and Actinomyces viscosus. Whole cells of serotype b S. mutans and Staphylococcus epidermidis were agglutinated upon addition of 3G6 mAb, while those of most other species were not significantly affected by this procedure. A hapten inhibition study showed that glycerophosphate was only a potent inhibitor of passive hemagglutination reactions between LTA coated sheep erythrocytes and 3G6 mAb.

Animals↗
PubMed1984

Electromechanical effects of bepridil on rabbit isolated hearts.

Electromechanical effects of a new antianginal agent, bepridil, on Langendorff-perfused rabbit hearts were compared with those of verapamil and lidocaine. Bepridil at concentrations above 2 X 10(-7)M caused a dose-related decrease in heart rate (HR), a prolongation of the atrio-His bundle conduction time (A-H interval) and a prolongation of the functional refractory period (FRP) of the atrioventricular (A-V) node. Similar changes in HR, A-H interval and the FRP of the A-V node were observed with verapamil at concentrations above 2 X 10(-8)M. Lidocaine at above 4 X 10(-5)M prolonged slightly the A-H interval and the FRP of the A-V node but did not decrease the HR. Bepridil at concentrations above 10(-6)M prolonged both the His bundle-ventricular conduction time (H-V interval) and the effective refractory period (ERP) of ventricular muscles. Similar changes in the H-V interval and in the ERP of ventricular muscles were observed with lidocaine at above 10(-5)M. Verapamil ranging between 5 X 10(-8)M and 8 X 10(-7)M had no effect on the H-V interval and appreciably shortened the ERP of ventricular muscles. Bepridil at concentrations above 2 X 10(-6)M reduced the developed tension as did verapamil at above 10(-7)M. On a molar basis, the depressant effect of bepridil on HR and the A-V nodal conduction, which may reflect inhibitory action on the slow channels, was less than one tenth that of verapamil. Bepridil was more potent than lidocaine in prolonging the H-V interval and the ERP of ventricular muscles indicating a possible inhibition of the fast sodium channels. Both of these electrophysiological effects of bepridil may afford significant bases for the antiarrhythmic action of the drug.

Animals↗
PubMed1984

Effects of bepridil on the electrophysiological properties of guinea-pig ventricular muscles.

Effects of bepridil, a new antianginal and potential antiarrhythmic agent, on transmembrane action potentials of ventricular muscles were examined in isolated right ventricular papillary muscles of guinea-pig. Bepridil at concentrations above 5 X 10(-6)M caused a dose-dependent decrease in both the maximum upstroke velocity (Vmax) and the action potential duration from the upstroke to 30% repolarization ( APD30 ). On the other hand, the resting potential (RP), the amplitude of action potential (AMP), and the action potential duration from the upstroke to 90% repolarization ( APD90 ) were not affected even at the highest concentration applied (10(-5)M). The curves relating membrane potential and Vmax were shifted by bepridil at 5 X 10(-6)M along the voltage axis in the direction of more negative potentials. The recovery kinetics of Vmax assessed by premature stimuli were definitely slowed by bepridil at above 10(-6)M. This effect was more pronounced with higher [K+]o (10 mM) than normal [K+]o (5 mM). Bepridil at 5 X 10(-6)M caused a rate-dependent decrease of Vmax (use-dependent block) with rapid onset and offset, as did lidocaine. Slow responses, which had been induced by isoprenaline (5 X 10(-6)M) in K+-depolarized preparations, were suppressed significantly by additional application of bepridil at 10(-5)M. These findings suggest that bepridil has electrophysiological characteristics similar to those both of Class Ib and Class IV antiarrhythmic drugs.

Action Potentials↗
PubMed1984

Isolation of paralysis-inducing murine leukemia viruses from Friend virus passaged in rats.

Four clones of murine leukemia viruses (PVC-111, PVC-211, PVC-321, and PVC-441) were isolated from a paralyzed Fischer rat which had been infected with rat-passaged Friend leukemia virus. PVC-211 and PVC-321 viruses induced hind leg paralysis in rats and killed them within 1 month, and PVC-441 did so within 2 months after infection, whereas PVC-111 did not within 4 months. PVC-321 and PVC-441 but not PVC-111 virus grew well in brain and spinal cord media. The viral antigens were found often in glia cells and rarely in neurons of the rats infected with each of these PVC viruses. All of the PVC viruses induced neuronal degeneration but neither inflammation nor leukemic infiltration in the spinal cord. The isolated viruses were all ecotropic and NB-tropic. Age dependency of the susceptibility of rats to paralysis induction was observed.

Animals↗
PubMed1984

[Changes of the DNA synthesis and the amount of S-100 protein associated with the morphological differentiation of cultured glioma cells].

S-100 protein is a highly acidic protein unique to the nervous system and exists predominantly in the cytoplasm of glial cells in a water-soluble form. The exact biological function is still unknown in spite of its well-known biochemical properties. Some investigators have reported that the amount of S-100 protein in developing brains increased in proportion to the brain's development and differentiation. In order to clarify the relationship between S-100 protein and differentiation of glial cells the changes of DNA synthesis and the amount of the water-soluble S-100 protein were investigated on cultured rat glioma (C-6) cells in the course of the morphological differentiation induced by dibutyryl cyclic AMP (dbc-AMP). C-6 cells were cultured in Eagle's minimum essential medium supplemented with 10% fetal calf serum and incubated in a humidified atmosphere of 5% CO2-95% room air at 37 degrees C. Dbc-AMP was added to the media at the concentration of 1 mM, and the media were changed every 48 hrs. A flow cytometric analysis of DNA histogram patterns was performed to investigate the changes of DNA synthesis using a Cytofluorograf FC 4800 A-50 (Bio/Physics). The changes of the amount of S-100 protein were examined by micro-complement fixation assay as described by Levine using rabbit antisera against bovine S-100 protein. Dbc-AMP inhibited the growth of C-6 cells remarkably and induced morphological changes resembling normal astrocytes.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1984

Effect of T-cell transfer on Pneumocystis carinii infection in nude mice.

The effect of transfer of spleen lymphocytes from euthymic heterozygote littermates (nu/+) or rabbit antiserum on Pneumocystis carinii (P. carinii) infection in nude (nu/nu) mice was investigated. After intravenous administration of nu/+ spleen T-cells, the number of cysts in the lung of previously infected mice was markedly decreased at day 14 and further at day 30. Intense cellular reactions were seen at day 14 and subsided lesions at day 30. Increased IgG antibody titers were observed at days 14 and 30. Multiple treatments with immune rabbit serum after infection were not effective for reducing the cyst number in the lung, neither enhanced cellular reaction, while the immune serum administered prior to infection prolonged the survival time. The results indicated an important role of T-cell mediated immunity for the resistance to P. carinii infection in mice.

Animals↗
PubMed1984

Experimental Pneumocystis carinii infection in nude rats.

The role of cell-mediated and humoral immunities to Pneumocystis carinii infection was studied on athymic nude rats and their heterozygous euthymic littermates inoculated intranasally with 10(6) cysts. Some of both groups were injected subcutaneously with cortisone (25 mg) twice a week. At 30 and 60 days postinoculation a large number of cysts were detected in the lung of cortisone treated euthymic rats as well as athymic rats with or without cortisone treatment. IgG antibody appeared in all groups of rats at 60 days post-inoculation while IgM antibody was not detectable. Delayed type footpad reaction to P. carinii antigen was recognized in euthymic rats without cortisone at 4 and 5 weeks postinfection but not in those rats with cortisone or without infection. These results suggest that cell-mediated immunity is important for protection of P. carinii infection in rat.

Animals↗
PubMed1984

Identification and quantitative determination of fentanyl metabolites in patients by gas chromatography--mass spectrometry.

Although fentanyl has been used widely as a short-acting narcotic analgesic, its metabolism in humans has not been clarified. In this study, three fentanyl metabolites were identified in the urine of eight surgical patients receiving 0.3-0.5 mg of fentanyl intravenously. The metabolites 4-N-(N-propionylanilino)piperidine, 4-N-(N-hydroxypropionylanilino)piperidine and 1-(2-phenethyl)-4-N-(N-hydroxypropionylanilino)piperidine, and unchanged fentanyl were identified by GC-mass spectrometry in urine collected 6 h after administration. Fentanyl and its main metabolite, 4-N-(N-propionylanilino)piperidine, were determined quantitatively in the urine of five additional patients receiving 0.5 mg fentanyl intravenously. Urinary excretion of fentanyl and 4-N-(N-propionylanilino)-piperidine during the first 12 h after injection accounted for 0.3-4.0% and 26 to 55% of the dose, respectively.

Adult↗