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Biomedical subjects

N Fujii

Publications and source records attributed to N Fujii.

At least 487 records · Page 27Linked to original sources
PubMed1987

Increased activity of oligo-2',5'-adenylate synthetase in Down's syndrome and epilepsy.

The level of oligo-2',5'-adenylate synthetase activity is a good marker for the response of cells to interferon. This enzyme can polymerize ATP to form oligonucleotides in the presence of double-stranded RNA, i.e. polyinosinate-cytidylate in vitro. The activity of this enzyme in peripheral blood mononuclear leucocytes was significantly increased in Down's syndrome (P less than 0.01) and epilepsy (P less than 0.01) compared with that in healthy controls, but the increase of activity was not significant in multi-infarct dementia (MID) (P greater than 0.05). Although the patients with Down's syndrome showed higher levels of this enzyme activity than the controls, interferon activity was never detected in the circulation. In addition, the serum of patients with Down's syndrome lacked the capacity to induce this enzyme in NC-37 and FL cells, and furthermore it was shown that the inhibitor of interferon activity was not found in the serum of patients. This discrepancy in Down's syndrome may be the result of the hypersensitivity of cells to interferon. On the contrary, interferon activity (32 IU/ml) was detectable in the circulation of one patient with epilepsy, and the serum of this patient had the capacity to induce this enzyme in NC-37 and FL cells.

2',5'-Oligoadenylate Synthetase↗
PubMed1986

H-NMR studies of calmodulin: the effect of W-7 (N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide) and Ca2+ on conformational changes of calmodulin.

The effect of W-7 (N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide), a calmodulin antagonist, on the structure of calmodulin was studied with 400 MHz H-NMR. W-7 affected the calcium-induced conformational change of calmodulin in several resonances. One resonant peak was assigned to the His-107 H2 proton. The other peaks were seen in the area of the methionine methyl group (around 2 ppm) and the high-field methyl group (0-1 ppm), these peaks cannot be assigned. The modifying effect of W-7 on the methyl-group resonances of calmodulin fully bound with Ca2+ was similar to that of trifluoperazine. However, the effect on the His-107 H2 proton was unique to W-7.

Calcium↗
PubMed1986

Genetic control of the immune response in mice to a Plasmodium falciparum sporozoite vaccine. Widespread nonresponsiveness to single malaria T epitope in highly repetitive vaccine.

Different H-2 congenic strains of mice were immunized with a P. falciparum sporozoite vaccine currently being tested in humans, or with different segments of the vaccine molecule. Specific IgG production or lymph node cell proliferation in response to different antigens was then determined. Only four of seven strains (representing three of eight possible different class II restriction molecules) responded to the vaccine. Of those restriction molecules, only one, I-Ab, was associated with a response to a malaria-encoded T epitope [contained within NP(NANP)3NA], while the other two molecules (E alpha dE beta d and E alpha kE beta s) were associated with a T cell response to a nonmalarial epitope(s) carboxyterminal to the malaria sequence and encoded by a tetracycline resistance gene, read out of frame. If an analogous situation applies in humans, natural boosting by sporozoites will be very restricted. This has serious implications for the effectiveness of the vaccine, since constant high levels of antisporozoite antibodies and possibly antibody-independent T cell effector functions are required for immunity.

Animals↗
PubMed1986

Characterization of a diphosphonopentaosylceramide containing 3-O-methylgalactose from the skin of Aplysia kurodai (sea hare)

The complete structure is proposed for a ceramide (Cer), bis(2-aminoethylphosphono)-pentaoside, isolated from the skin of Aplysia kurodai. This new phosphonoglycosphingolipid was purified using two systems of column chromatography on silicic acid. The purity of the glycolipid was confirmed by thin-layer chromatography, analysis of its composition, and proton magnetic resonance spectrometry. The component carbohydrates were glucose, galactose, N-acetylgalactosamine, and 3-O-methylgalactose. Most (90%) of the fatty acid was palmitic acid and the major sphingosine bases were octadeca-4-sphingenine (51%) and anteisononadeca-4-sphingenine (38%). 2-Aminoethylphosphonyl-6-galactose was identified after its partial hydrolysis. From studies by methanolysis, permethylation, mild acid hydrolysis, hydrogen fluoride treatment, chromium trioxide oxidation combined with thin-layer chromatography, gas liquid chromatography, gas chromatography-mass spectrometry, and proton magnetic resonance spectrometry, the structure of the glycolipid was concluded to be 3-OMeGal beta 1----3GalNAc alpha 1----3[6'-O-(2-aminoethylphosphonyl)-Gal alpha 1----2](2-aminoethylphosphonyl----6)Gal beta 1----4Glc beta 1----1Cer.

Animals↗
PubMed1986

Antithrombogenic heparinized polyacrylonitrile copolymer.

A new antithrombogenic polymer was synthesized by the photograft-copolymerization of methoxypolyethyleneglycol methacrylate and dimethylaminoethyl methacrylate to polyacrylonitrile containing bromine atoms, and by quaternizing and heparinizing the graft-copolymer. Hydrophilicity and heparin content of the polymer could be controlled by changing the feed ratio of the acrylates to be grafted. The heparinized polymer showed excellent mechanical and antithrombogenic properties.

Acrylic Resins↗
PubMed1986

Human calcitonin gene-related peptide possesses weak inhibitory potency of bone resorption in vitro.

Synthetic human calcitonin gene-related peptide (CGRP) was examined for the action on the bone in vitro. Human CGRP inhibited bone resorption stimulated by both human parathyroid hormone and basal. The mode of inhibitory action of human CGRP seemed to be similar to that of calcitonin and the relative potency of human CGRP to inhibit bone resorption is one five-hundredth of that of human calcitonin. Thus, a novel pharmacological action of CGRP was demonstrated.

Animals↗
PubMed1986

Induction of oligo-2',5'-adenylate synthetase in human lymphoid cells treated with 5-azacytosine and 5-iododeoxyuridine.

Oligo-2',5'-adenylate synthetase activity was investigated in several human lymphoblastoid cell lines of B cell origin treated with reagents having effects on gene expression, 5-azacytosine (5AZct), 5-azacytidine (5AZcd) and 5-iodo-2'-deoxyuridine (IUdR). Enzyme activity did not increase in cells treated with 5AZcd, but the other reagents induced significant levels of activity. Interferon (IFN) activity was not detected in culture fluids of cells treated with 5AZcd or 5AZct. On the other hand, treatment of cells with IUdR led to the production of 5 to 10 units/ml IFN by NC-37 and Raji cells, but not by other human B cell lines. Enzyme induction by IUdR occurred in IFN-producing cells, NC-37 and Raji, exposed to anti-IFN-alpha sera and also in IFN-non-producing human B cells. The effect of 5AZct on enzyme induction was observed only after cultivation of cells for more than 1 month. This compound could not induce enzyme activity in Epstein-Barr virus (EBV)-negative cells, BJAB, but only in the EBV-positive cell lines NC-37 and Raji. In contrast, treatment of cells with IUdR for only 3 days induced the enzyme in all human lymphoblastoid cell lines of B cell origin except P3HR-1, but not in other human cell lines, FL, HeLa and K562. Oligo-2',5'-adenylate synthetase activity in P3HR-1 cells, which produce EBV particles, was hardly affected by IUdR or IFN treatment.

2',5'-Oligoadenylate Synthetase↗