Amino acid transport system of the guinea pig small intestine is injured by hydroxyl radicals.

The mechanism for the damage to the alanine-preferring amino acid transport system (A system) of guinea pig intestinal brush border membrane vesicles induced by active oxygen species was studied in vitro. The transport activity of L-proline, which is a model amino acid for the A system, and the tryptophan fluorescence intensity of intestinal brush border membrane vesicles were decreased, and lipid peroxidation of these membrane vesicles was induced by ultraviolet irradiation, which generated active oxygen species. Thiourea (hydroxyl radical scavenger) protected L-proline transport activity and tryptophan fluorescence intensity of intestinal brush border membrane vesicles and also inhibited lipid peroxidation in these membrane vesicles in the presence of active oxygen radicals.

Partial cloning of cDNA for hamster liver cholesterol 7 alpha-hydroxylase.

A partial cDNA clone encoding cholesterol 7 alpha-hydroxylase (pHA 7 alpha-3) was isolated from a hamster liver cDNA library using rat P-450 ch7 cDNA (p 7 alpha-11) as a probe. In comparison with the complete base sequence of p 7 alpha-11, pHA 7 alpha-3 lacked about 500 base pairs at the 5' end. Circadian rhythms of mRNA for hamster liver 3-hydroxy-3-methylglutaryl coenzyme A reductase and cholesterol 7 alpha-hydroxylase were investigated with cDNA clones encoding 3-hydroxy-3-methylglutaryl coenzyme A reductase (pRed-227) and pHA 7 alpha-3.

Effect of dietary hydrogenated corn oil (trans-octadecenoate rich oil) on plasma and hepatic cholesterol metabolism in the hamster.

The effect of dietary hydrogenated corn oil (trans-octadecenoate-rich oil) on plasma cholesterol and triglyceride concentrations was compared with dietary palmitic acid in hamsters given a cholesterol-rich diet. The addition of dietary palmitic acid and hydrogenated corn oil accelerated the increase in plasma VLDL- and LDL-cholesterol levels and plasma triglyceride level induced by dietary cholesterol loading. Dietary cholesterol, palmitic acid and hydrogenated corn oil showed no effect on plasma HDL-cholesterol concentration.

Role of cholesterol-accumulating macrophages on vascular smooth muscle cell proliferation.

The proliferation of vascular smooth muscle cells (VSMC) was stimulated by co-incubation with macrophages. Further stimulation was observed when co-incubated macrophages were supplied with LDL or cholesterol. However, the stimulation of VSMC proliferation did not result from co-incubation with macrophages supplemented with acetylated LDL or delipidated LDL.

Analysis of neutral amino acid transport systems in the small intestine: a study of brush border membrane vesicles.

Transport of L-proline, L-leucine and L-cysteine was studied in brush border membrane vesicles prepared from guinea pig ileum. Concentrative transport of L-proline, L-leucine and L-cysteine was obtained in the presence of an Na+ gradient from, outside to inside of the vesicles, which indicated contribution of either system A (alanine-preferring) or system ASC (alanine-, serine- and cysteine-preferring) to the transport. When Na+ was replaced by Li+, L-leucine and L-cysteine maintained the same concentrative transport.

Determinants of left atrial systolic time intervals--assessment by pulsed Doppler echocardiography.

To evaluate the responsible factors for left atrial ejection, the left atrial preejection period (LAPEP), i.e., the time interval between atrial pacing pulse and onset of atrial ejection, and left atrial ejection time (LAET), i.

[Clinical electrophysiological effects of nicorandil on the conduction system in humans].

The electrophysiological effects of nicorandil on the conduction system in humans were examined. Twelve patients with sick sinus syndrome (SSS), 3 patients with AV block and 3 subjects with normal conduction system were studied. The clinical electrophysiological effects were examined before, and 5 min after intravenous administration of nicorandil 2 mg over 3 min.

[A case of cardiac tamponade showing respiratory variation in inflow and outflow velocities in both ventricles and venous return].

A case of a 62-year-old man with a large pericardial effusion is presented. He developed clinical signs of cardiac tamponade. Two-dimensional echocardiography revealed collapse of the right ventricle in early diastole and inversion of the free wall of both atria in systole.

[Clinical estimation of coronary risk factors with special reference to coronary arteriographic findings].

The relationship between coronary risk factors and the severity of coronary artery stenosis (coronary score: CS) was estimated in 225 male subjects (aged 29-82 years, median 60 years old) who had undergone coronary arteriography for suspected coronary heart disease. CS was positively related to age, and levels of fasting blood sugar, uric acid, total cholesterol, low density lipoprotein cholesterol, and apolipoprotein B. Alcohol consumption, apolipoprotein AI and AII levels were inversely correlated to CS.

Assessment of supra-valvular abnormal signal with color Doppler flow mapping in patients with aortic regurgitation.

A supra-aortic abnormal flow signal (proximal acceleration) was studied in 62 patients with aortic regurgitation with the use of color Doppler flow mapping. The proximal acceleration signal was detected in 28 of the 62 patients and was shaped like a V or a teardrop. In the 29 patients who underwent aortography, a proximal acceleration signal was observed in all 18 patients with severe and moderate regurgitation and in only one of the 11 patients with mild regurgitation.

[Secundum atrial septal defect in two families].

Two families having secundum atrial septal defect (ASD) were reported. In one family, a 31-year-old male and his 60-year-old mother had secundum ASD without PR prolongation. His 38-year-old brother was diagnosed as having ASD.

[Hemodynamic responses to sublingual nifedipine during exercise and recovery in congestive heart failure].

To elucidate the hemodynamic responses to sublingual nifedipine administration during exercise and recovery in congestive heart failure, 16 patients with dilated cardiomyopathy (DCM) and 11 controls were studied using supine bicycle exercise testing. The cardiac index (CI) was measured at rest, at peak exercise and successively during recovery by the thermodilution method. The heart rate (HR), mean blood pressure (mBP) and mean pulmonary arterial pressure (mPAP) were measured every minute.

[Left atrial systolic time intervals: their relations to left atrial preload, afterload and acute left ventricular pressure loading].

Using pulsed Doppler echocardiography, the left atrial pre-ejection period (LAPEP) and left atrial ejection time (LAET) were studied in relation to left atrial loading and acute left ventricular pressure loading conditions in 17 patients with various heart diseases. LAPEP was defined as the time interval from the onset of a right atrial pacing pulse to the upstroke in the atrial contraction phase on the mitral flow velocity pattern; LAET was defined as the duration of left ventricular filling due to atrial contraction. 1.

[Left ventricular diastolic reserve during acute pressure loading in hypertrophic cardiomyopathy and dilated cardiomyopathy].

To evaluate left ventricular diastolic reserve during acute pressure loading, changes in mitral flow velocity patterns before and after the elevation of blood pressure were analyzed by pulsed Doppler echocardiography in 11 cases of hypertrophic cardiomyopathy (HCM), nine cases of dilated cardiomyopathy (DCM), and 11 control subjects. Systolic blood pressure was elevated 25% above basal values by methoxamine infusion (0.01 mg/kg/min).

Periarteritis of coronary arteries with severe eosinophilic infiltration. A new pathologic entity (eosinophilic periarteritis)?

A 40 year-old male presented symptoms of angina pectoris for about nine years and expired with symptoms of unstable angina, changing pattern at the terminal stage. At autopsy, both right and left coronary arteries of the subepicardial region were grayish white and elastic hard. Histologically, inflammatory infiltration was localized in adventitia of coronary arteries located in the subepicardial region.

[The suction signal detected by color Doppler echocardiography in patients with mitral regurgitation: its clinical significance].

The present study clarified the clinical significance of the suction signal--regurgitant signal near the mitral valve in the left ventricle--as obtained by two-dimensional color Doppler echocardiography in patients with mitral regurgitation. The study population consisted of 39 patients with various heart diseases having mitral regurgitation. The presence of a mitral regurgitant signal was determined not only in the left atrium but in the left ventricle using the long-axis view, four-chamber view, and short-axis view.

Premature opening of the pulmonary valve in endomyocardial fibrosis.

Two-dimensional and Doppler echocardiographic findings in a 67-year-old man with endomyocardial fibrosis (EMF) are described. The two-dimensional echocardiogram showed typical features of EMF, right ventricular endomyocardial calcification, a thickened right ventricular wall, obliteration of the apex of the right ventricle and marked dilatation of the right atrium. In addition, premature opening of the pulmonary valve was observed during late diastole.

[Echo and Doppler cardiographic findings of isolated quadricuspid aortic valve: a case report and a review of the literature].

The two-dimensional and pulsed Doppler echocardiographic features of a case of isolated quadricuspid aortic valve with aortic regurgitation are described. A 62-year-old woman was hospitalized for exertional palpitation and dyspnea. Her physical examination showed the typical findings of aortic regurgitation.