Search PubMed⌕ Search

Biomedical subjects

M Matsuo

Publications and source records attributed to M Matsuo.

At least 559 records · Page 31Linked to original sources
PubMed1978

Electron spin resonance studies of radicals obtained by the reaction of alpha-tocopherol and its model compound with superoxide ion.

alpha-Tocopherol (vitamin E) and its model compound, 6-hydroxy-2,2,5,7,8-pentamethylchroman, were found to be oxidized by O2- to yield free radicals which were detected at room temperature by ESR spectroscopy. The ESR spectra of these radicals showed seven main lines with additional hyperfine structure and have the same g-values at 2.0046. Assignments of the ESR spectra were done on the basis of the spectra of the free radicals of deuterated hydroxypentamethylchroman obtained from the same reaction with O2-. The radicals observed are chromanoxyls generated by the abstraction of hydrogen from the 6-hydroxy group of tocopherols.

Electron Spin Resonance Spectroscopy↗
PubMed1978

Evidence for an essential arginine recognition site on adenosine 3':5'-cyclic monophosphate-dependent protein kinase of rabbit skeletal muscle.

On the basis of the chemical and structural features of the amino acid sequences in the vicinities of phosphorylatable hydroxyamino acid residues in several of the well-known protein substrates for skeletal-muscle cyclic AMP-dependent protein kinase, it is hypothesized that the phosphorylatable residue at position i and arginine residue at position i-3 of these protein substrates are located on a peptide turn on the hydrophilic protein surface. It is further hypothesized that there is an arginine-recognition site near the active centre on the protein kinase. This site is essential for the function of cyclic AMP-dependent protein kinase, for, not only does it recognize specifically the exposed arginine residue of the protein substrate, but, more importantly, via the interaction with arginine-(i--3), it may help to steer the topologically adjacent serine-i into proper orientation on the nearby active centre for phosphorylation. Model-building and kinetic data that provide support for the proposed hypotheses are presented.

Adenosine Triphosphate↗
PubMed1978

Congenital generalized lipodystrophy with insulin-resistant diabetes.

Hyperglycemia, glucose intolerance, hyperinsulinemia and resistance to exogenous insulin were found in a 10-year-old Japanese boy diagnosed as having congenital generalized lipodystrophy. Studies on insulin receptors of circulating mononuclear leucocytes indicated that insulin-resistant diabetes combined with congenital generalized lipodystrophy may be due to disturbance of insulin binding to membrane receptors. No insulin-binding antibody or antibody that impairs insulin-receptor binding was found. Plasma glucagon showed an exaggerated response to L-arginine before treatment. After treatment with a controlled diet and an oral sulfonylurea (500 mg/day) for 4 weeks, there was improvement in the plasma glucagon response to L-arginine. Improvement in the hyperglycemia, hyperinsulinemia and acanthosis nigricans was also observed. On the other hand, on completion of a 7-day high-fat diet, a marked increase in serum free fatty acids, triglycerides and beta-lipoproteins was observed. The total plasma post-heparin lipolytic activity during the high fat diet was within the normal range. However, the level of protamine-inactivated activity was 3 times that of the control.

Acanthosis Nigricans↗
PubMed1978

Computer analysis of periventricular lucency on the CT scan.

Of 53 patients with periventricular lucency, 70% revealed obstructive hydrocephalus, mainly due to infratentorial tumors, and the remainder were cases of communicating hydrocephalus, usually secondary to subarachnoid hemorrhage. Of the patients with PVL, 95% had hypertensive hydrocephalus and 60% showed slightly dilated ventricles. Computer analysis was helpful in displaying PVL objectively and clarifying its nature. In experimentally induced obstructive hydrocephalus, PVL was observed at the acute hypertensive stage. We concluded that the pathogenesis of PVL might be the passive diffusion or acute extravasation of CSF into white matter through the disrupted ventricular wall, rather than transependymal absorption of CSF.

Animals↗
PubMed1978

Ageing of chick embryo fibroblasts in vitro. II. Relationship between cell proliferation and increased multinuclear cells.

The cell lines of chick embryo fibroblasts obtained from different embryos were sequentially cultivated and relationship between growth potential and increased multinuclear cells was examined. During ageing in vitro multinuclear cells increased with decreasing growth rate. Their percentage in the senescent cell populations reached 11--15% when the cells stopped growing, and 20--25% just before the cultures died out. This phenomenon may be useful as a parameter for cellular ageing. Most of the multinuclear cells were binucleates. The mean cell volume of the cells also increased through their lifespan with a sharp rise at the latest passages.

Aging↗