Search PubMed⌕ Search

Biomedical subjects

H Aoki

Publications and source records attributed to H Aoki.

At least 577 records · Page 32Linked to original sources

Some characteristics of cytosol binding protein for 1 alpha,25-dihydroxycholecalciferol, 24R,25-dihydroxycholecalciferol and 25-hydroxycholecalciferol in rat parotid gland.

1. 1 alpha,25-dihydroxycholecalciferol (1,25-(OH)2VD3), 24R,25-dihydroxycholecalciferol (24,25-(OH)2VD3) and 25-hydroxycholecalciferol (25-OHVD3) binding proteins were existed in cytosol of rat parotid gland. 2. The dissociation constants of binding proteins for 1,25-(OH)2VD3, 24,25-(OH)2VD3 and 25-OHVD3 were 3.15 x 10(-9), 5.05 x 10(-9) and 6.60 x 10(9) M, respectively. 3. The mol wt and the isoelectric point (pI) of binding proteins for 1,25-(OH)2VD3, 24,25-(OH)2VD3, 24,25-(OH)2VD3 and 25-OHVD3 were the same to each other (with mol wt of 155,000 and pI of 4.87). 4. The binding specificity of 1,25-(OH)2VD3 binding protein was similar to that of 24,25-(OH)2VD3 and 25-OHVD3 binding protein. 5. The extent of loss of binding activity for 1,25-(OH)2VD3 by pronase and trypsin was much greater than that of binding activity for 24,25-(OH)2VD3 and 25-OHVD3.

Animals↗

Role of viral glycoproteins in haemolysis by influenza B virus.

Influenza B virus exhibited haemolytic activity at low pH, but the pH profile for its activity varied from strain to strain. The results of selective heat-inactivation of the enzyme activity of neuraminidase (NA) or elimination from virions of the enzyme-active portion of the NA molecule by trypsin digestion, suggest that proteolytically cleaved haemagglutinin, but not enzyme activity of NA, is essential for haemolysis by influenza B virus.

Animals↗

Studies on a new immunoactive peptide, FK-156. II. Fermentation, extraction and chemical and biological characterization.

An interesting immunoactive peptide, FK-156, has been isolated from the fermentation broth of Streptomyces olivaceogriseus sp. nov. and Streptomyces violaceus. The compound was purified by column chromatography with activated carbon, ion exchange Sephadex and cellulose powder. FK-156, obtained as white powder, exhibits a wide variety of immunostimulatory activity in vivo and in vitro with experimental animals. Pretreatment of mice or rats with this peptide protected the animals against lethal infection with Escherichia coli and resulted in prolongation of life span of tumor bearing animals.

Adjuvants, Immunologic↗

Studies on new vasodilators, WS-1228 A and B. I. Discovery, taxonomy, isolation and characterization.

New vasodilators, designated WS-1228 A and B have been discovered in the culture filtrate of a strain of Streptomyces aureofaciens. The active compounds were purified by column chromatography with Diaion HP-20 and silica gel, and finally separated from each other by high performance liquid chromatography. They were obtained as pale yellow crystals and their molecular formulae were both C11H17N3O.

Animals↗

Involvement of the dopaminergic system in the regulation of the caudate spindle in the rat.

In an attempt to study the neural mechanism of the development of the caudate spindle, effects of dopamine agonist or antagonists and baclofen on the spindle were studied in gallamine-immobilized rats. The spindle was significantly enhanced by chlorpromazine, haloperidol and pimozide, and these effects of drugs were completely antagonized by apomorphine. A marked prolongation of the duration of the spindle was observed by the treatment with baclofen, and this side effect was antagonized by apomorphine but not by methysergide, eserine or picrotoxin. These results suggest that the dopaminergic system may play an important role in the development of the caudate spindle in the rat, i.e. as a negative modulatory system in the manifestation of the caudate spindle.

Action Potentials↗

Effect of helper T cells on prevention of tolerance induction in effector T cells responsible for syngeneic tumor immunity.

The present study investigates the role of helper T cells in preventing tolerance in effector T cells responsible for syngeneic tumor immunity. Tolerance in T cell-mediated immune responses against X5563 plasmacytoma was induced in syngeneic C3H/He mice by intravenous (iv) administration of 7,000 R X-irradiated X5563 tumor cells. Since the anti-X5563 tumor tolerance was observed irrespective of whether the tumor cells had been modified with trinitrophenyl (TNP) hapten prior to iv inoculation, the ability of TNP-reactive helper T cells to prevent the tolerance induced by iv inoculation of TNP-X5563 tumor cells was examined. TNP-reactive helper T cell activity was generated in C3H/He mice by immunization with TNP-isologous mouse gamma-globulin after inoculation with the TNP-conjugate of a non-immunogenic co-polymer of D-glutamic acid and D-lysine. Intravenous inoculation with TNP-modified X5563 cells induced tolerance in mice not primed with TNP. However, such tolerance was prevented in mice in which TNP-reactive helper T cell activity had been generated. These results indicate that helper T cells play a crucial role in preventing effector T cell tolerance. The mechanisms by which tolerance induction in effector T cells is circumvented are discussed in relation to the generation and delivery of signals required for T cell activation.

Animals↗