Keizo Ohmori

Risk factors of atherosclerosis and aortic pulse wave velocity.

Aortic pulse wave velocity (PWV) is a noninvasive technique that can estimate aortic stiffness or organic change quantitatively. The authors examined the correlation between age and the PWV value in 113 subjects and also examined the relationship between ather osclerotic associated diseases and PWV. A positive correlation was observed between age and the PWV value. No significant difference was found in the PWV value between groups with and without risk factors of atherosclerosis. No significant difference was observed in the PWV value between groups with and without a history of atherosclerotic disease.

Successful Treatment of Intermittent Claudication Due to Spinal Canal Stenosis Using Beraprost Sodium, a Stable Prostaglandin I2 Analogue: A Case Report

The syndrome of intermittent claudication can be induced not only by vascular insuffi ciency of the lower limbs but also by diseases of the spinal cord and cauda equina. The authors describe a sixty-year-old man with intermittent claudication due to spinal canal stenosis who was successfully treated with beraprost sodium, a stable prostaglandin I2 analogue. This drug has a long biological half-life and is orally effective in vasodilation, which is suggested to be beneficial in treating this syndrome. Beraprost sodium may become one of the major drugs for conservative therapy of intermittent claudication induced by spinal canal stenosis.

Cerebral Infarction in a Young Adult Associated with Protein C Deficiency A Case Report

Protein C deficiency is a cause of thromboembolic disease. Venous thrombosis is the most common clinical manifestation. Arterial thrombosis is unusual and involvement of the intracranial arteries is especially rare. Herein the authors describe a case of cerebellar infarction associated with protein C deficiency and review the relevant medical literature. A thirty-year-old man was hospitalized because of dysarthria, right limb ataxia, and a gait disturbance. Cranial computed tomography disclosed an infarction in the right cerebellar hemisphere and brachium pontis. Three months earlier the patient had had a transient ischemic attack with truncal ataxia and gait disturbances. On admission, the protein C antigen was 57% and protein C activity was 45%. Investigation of family members revealed protein C deficiency in an uncle. Literature review of stroke cases associated with protein C deficiency revealed that most had had a previous vascular event and/or a positive family history or had used oral contraceptives chronically. Protein C deficiency should be considered in young stroke patients with a positive family history of vasooc clusive disease, previous ischemic events, or chronic oral contraceptive use.

Tissue-specific and non-tissue-specific heavy-chain isoforms of myosin in the brain as revealed by monoclonal antibodies

Four types of monoclonal antibody (BM-1, BM-2, BM-3 and BM-4) each having distinctive tissue specificity were obtained by immunizing mice with purified bovine cerebrum myosin. Both BM-1 and BM-2 reacted most efficiently with cerebrum myosin and less efficiently with myosins from other limited nonmuscle tissues, the tissue specificity of BM-1 being much narrower than that of BM-2. BM-3 reacted more efficiently with several other nonmuscle myosins than with cerebellar or cerebral myosin. BM-4 recognized various nonmuscle and smooth muscle myosins with a nearly equal efficiency. Cerebral myosin as well a cerebellar myosin contained two or more electrophoretic variants of the heavy chains. BM-1 and BM-3 as well as BM-2 and BM-3 were found to recognize selectively these distinct heavy-chain isoforms. The antigenic sites of the three tissue-specific antibodies (BM-1, BM-2 and BM-3) were all localized near the head/tail junction of the myosin molecules, while that of non-tissue-specific antibody BM-4 was near the center of the tail. These and additional results indicate that mammalian brain tissues as well as several other nonmuscle tissues contain multiple heavy-chain isoforms of myosin, the levels of which differed considerably from one tissue to another.

Quantitative analysis of antiatherosclerotic effect of nifedipine in cholesterol-fed rabbits

SummaryReports concerning the effect of slow calciumchannel blockers on experimental atherosclerosis are controversial. We examined the antiatherosclerotic effect of nifedipine (40 mg/day for 16 weeks) on aorta of rabbits on diets containing 0.3%, 0.5%, and 1.0% cholesterol. There were no significant differences in levels of serum lipids with or without nifedipine in the same cholesterol-fed rabbits. The results obtained show that nifedipine suppressed the extent of lipid deposition and surface involvement (S.I) in aorta in 0.3% cholesterol-fed rabbits, whereas nifedipine only tended to suppress S.I. in 0.5% cholesterol-fed rabbits and had no effect in 1.0% cholesterol-fed rabbits. The log dose-response relationship of S.I. was obtained by plotting the concentration of cholesterol in the feed or the “integrated value” of the total serum cholesterol (TC), i.e., the cumulative sum of the serum TC values obtained at each week. The log, doseresponse curve was shifted in parallel with the right in nifedipine groups. The Lineweaver-Burk plot constructed from the dose-response curve had the same points crossing the ordinate with or without nifedipine. These results suggested that nifedipine suppressed S.I. in a competitive manner with cholesterol on the specific binding site of lipid deposition. Electron-microscopic findings also demonstrated that fat droplets in smooth muscle cells, extracellular matrix containing collagen, and elastic fibers decreased in nifedipinetreated rabbits.

Granule-laden perivascular cells observed in rabbits with experimental cerebral atherosclerosis

Granule-laden perivascular cells distributed around the fine vessels in brain of hypertensive rabbits fed a cholesterol diet were examined by electron microscopy. Perivenule granule-laden cells contained secondary lysosomes, residual bodies, Golgi vesicles, fusion vesicles, and vacuoles. In periarteriole granule-laden cells, secondary lysosomes and vacuoles were not prominent. Findings indicated that the granule-laden cell may be a histiocyte that appears during the vascular reaction to hypertension and hypercholesterolemia. This vascular reaction may occur more strongly in the veins than the arteries.

Subclavian Steal Phenomenon Associated with Stress Polycythemia A Case Report

A case of stress polycythemia without symptoms of cerebral ischemia is presented. The patient demonstrated a blood flow reversal through the right vertebral artery that was caused by a complete obstruction of the right subclavian artery at its origin. This obstruc tion may have been due to thrombosis associated with stress polycythemia. This is a rare example of a case in which thrombotic complications of stress polycythemia occurred in a larger caliber vessel such as the subclavian artery.