Search PubMed⌕ Search

Biomedical subjects

N Nagao

Publications and source records attributed to N Nagao.

81 records · Page 5Linked to original sources

A D variant, Del?

Explore the source record for details and available documents.

Erythrocytes↗

Heterogeneity of the phenotype Jk(a-b-) found in Japanese.

Fourteen Jk(a-b-) persons were detected by testing 638,460 Osaka blood donors with an automated 2 M urea technique. Two of these 14 Jk(a-b-) samples were quite different from the hitherto reported Jk(a-b-) phenotype, and a family study showed that the mode of the inheritance was dominant. The red cell membranes of these Jk(a-b-) samples were studied by polyacrylamide gel electrophoresis and unusual protein bands (apparent mw, 67,000 d) were detected.

Blood Group Antigens↗

Cytotoxicity of docosahexaenoic acid and eicosapentaenoic acid in tumor cells and the dependence on binding to serum proteins and incorporation into intracellular lipids.

Docosahexaenoic acid (DHA) inhibited the DNA synthesis in Ehrlich ascites tumor cells more markedly than eicosapentaenoic acid (EPA), which was more inhibitory than oleic-, linoleic-, linolenic-, and arachidonic acids. Their activities augmented according to the increase of number of double bonds in the molecule. To correlate the cytotoxicity with lipid syntheses in the cells, distribution of EPA and DHA incorporated into cellular lipids was assessed. EPA was incorporated into triglycerides (TG) and DHA into phosphatidylcholine (PC). These synthesis into TG and PC etc., which shattered from cytotoxicity, may be involved in tumor-cellular protecting actions against EPA or DHA. EPA and DHA involved in cytotoxicity exhibition are their free acid forms. Thus, as an anticancer reaction, intracellular accumulation in the free acid form of DHA was more marked than that of EPA.

Animals↗

Anti-metastatic effect of an autooxidation-resistant and lipophilic ascorbic acid derivative through inhibition of tumor invasion.

The invasion of human fibrosarcoma HT-1080 cells through Matrigel was shown to be inhibited by pretreatment with ascorbic acid (Asc) or its four derivatives, such as Asc-6-O-palmitate (Asc6Plm), Asc-2-O-phosphate (Asc2P), Asc-2-O-phosphate-6-O-palmitate (Asc2P6Plm), and Asc-5,6-benzylidene (Asc5,6Bz) of non-cytotoxic concentrations for 1 or 18 hr. Two lipophilic derivatives such as Asc6Plm and Asc2P6Plm exerted an invasiveness-inhibitory activity more markedly with 1-hr pretreatment, being a more practical index in terms of the plasma half-life, than Asc, Asc5,6Bz or Asc2P being less lipophilic. Considerably less cytotoxicity (a > 3.3-fold higher IC50 for 1-hr pretreatment) of Asc2P6Plm sufficiently compensated a slightly lower invasiveness-inhibitory activity (a < 1.8-fold higher EC50) as compared with Asc6Plm. Pulmonary metastasis of mouse melanoma B16BL6 cells injected into the tail vein was also inhibited by intravenous administration with Asc2P6Plm dose-dependently. Thus Asc2P6Plm, a lipophilicity-hydrophilicity balanced molecule protectively blockd in the autooxidation-prone moiety, is anticipated as a potent anti-metastatic agent via inhibition of tumor invasion.

Animals↗

The signaling pathway of cardiotrophin-1 is not activated in hypertrophied ventricles of carnitine-deficient juvenile visceral steatosis (JVS) mice.

Cardiotrophin-1 (CT-1) is a novel cytokine which is involved in the growth and survival of cardiac cells. We examined whether CT-1 plays a role in the development of cardiac hypertrophy in carnitine-deficient juvenile visceral steatosis (JVS) mice. The CT-1 mRNA level was quantitatively measured by the competitive RT-PCR method. In contrast to other models including spontaneously hypertensive rats, CT-1 mRNA in the ventricles of JVS mice was comparable to the control at 5 days and was less than half the control value at 2 and 8 weeks when the ventricles of the JVS mice were highly hypertrophied. There were no significant differences in CT-1 mRNA levels in the lung, liver, kidney, small intestine and skeletal muscle between the JVS and control mice at 2 weeks. We did not find any difference between JVS and control mice at 2 weeks in the mRNA level of ventricular leukemia inhibitory factor (LIF) which binds to the same receptor as CT-1. Furthermore, almost no phosphorylated STAT3 (signal transducer and activator of transcription 3), downstream of the LIF receptor and the gp130 signaling subunit, was observed in the ventricles of JVS and control mice. These data show that the CT-1 signaling pathway does not play a significant role in the development of cardiac hypertrophy in JVS mice. Furthermore, we could not detect any differences in insulin-like growth factor I and II mRNA levels. All these data suggest distinct differences in the mechanisms of cardiac hypertrophy between JVS mice and other model animals.

Animals↗

Wool grease-derived alpha-monohydric fatty alcohols are carcinostatic depending on their branched alkyl moiety bulkiness.

Wool fatty alcohols (WF-Alc) separated from esterolysates of sheep cutaneous wax were fractionated by molecular distillation and HPLC, resulting in two homogeneous antitumor compounds identified by GC-MS and 13C-/1H-NMR as a-monohydric branched saturated fatty alcohols, 14-methyl-1-pentadecanol (iso-C16OH) and 14-methyl-1-hexadecanol (anteiso-C17OH). Both the alcohols markedly prolonged the life-span of Ehrlich ascites carcinoma- or S180 fibrosarcoma-implanted mice without acute toxic side-effects, whereas other iso- or n-fatty alcohols (C16-C30) contained in WF-Alc were slightly effective. Thus antitumor activity of WF-Alc depended on the molecular balanced hydrophobicity attributed to both the branched alkyl moiety bulkiness derived from the diverse fatty alcohols contained, and a hydroxyl group.

Animals↗