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Biomedical subjects

A Seki

Publications and source records attributed to A Seki.

At least 181 records · Page 10Linked to original sources

Fibrillatory wave size in paroxysmal atrial fibrillation.

Little attention has been paid to the atrial fibrillatory waves (f waves) in paroxysmal atrial fibrillation. The present study attempted (1) to compare the f wave size in paroxysmal atrial fibrillation with that in persistent fibrillation, and (2) to examine whether the f wave size can predict the development of persistent from paroxysmal atrial fibrillation. The size of the f waves was measured in 60 patients with paroxysmal atrial fibrillation of non-rheumatic etiology (group A), 87 patients with persistent atrial fibrillation of non-rheumatic etiology (group B), and 34 patients with persistent atrial fibrillation of rheumatic etiology (group C). The f wave size in group A was 1.1 +/- 0.1 mm (mean +/- SE) which was significantly smaller than 1.6 +/- 0.1 mm in group B and 2.2 +/- 0.2 mm in group C (p less than 0.01, respectively). Among patients with paroxysmal atrial fibrillation, persistent atrial fibrillation developed in 9 of 19 patients (47.4%) with f wave size of 1.2 mm or more, and only in 5 of 41 patients (12.2%) with f wave size of less than 1.2 mm. These results indicate that paroxysmal atrial fibrillation generally has smaller f waves than persistent atrial fibrillation, but that the presence of larger f waves indicates potential development of persistent atrial fibrillation.

Atrial Fibrillation↗

Effect of 2'-carboxymethoxy-4,4'-bis(3-methyl-2-butenyloxy)chalcone (SU-88) on gastric local blood flow.

Effect of 2'-carboxymethoxy-4,4'-bis(3-methyl-2-butenyloxy)chalcone (SU-88), a new anti-ulcer drug, on gastric tissue blood flow was investigated by using an inhaled hydrogen gas clearance method in rats. As a result, following the intravenous infusions of 10,20 and 30 mg/kg/h of SU-88, the gastric blood flow increased with an increase rate of 38.1, 70.5 and 61.7% as compared with the control value, respectively. Following the intraperitoneal administrations of 50 and 100 mg/kg of SU-88, the gastric blood flow increased by 59.8 and 51.2%, respectively, immediately after the administration.

Animals↗

The hand and environment (3)--physiological changes of digital functions in two age groups studied by vibratory stimulations and a cold water immersion.

Skin temperature, vibratory sensibility and pinch strength of the hand were recorded continuously in 20 healthy adults through two vibratory stress tests (32 Hz and 125 Hz) and a cold water (10 degrees C) immersion (for 10 min) test in a climatic chamber (20 degrees C, 50% humidity). As a stressor to the hand, the immersion was the most effective and the vibrator stress at 32 Hz was next. As a detector for function of the hand, vibratory sensibility at 125 Hz was proved to be the most valuable and the digital temperature was the next. As to aging, the mature age group showed low vibratory sensibilities at 63 Hz, higher digital temperatures, stronger pinch strengths, and quicker recoveries after the stress tests. Along the passage of time after entering the chamber, the vibratory sensibilities and the pinch strengths did not show any changes. However, the digital temperatures became continuously lower.

Adult↗

Experimental production of papillary muscle and mitral valve lesions by vagal manipulations in rabbits.

The present paper describes peculiar lesions in papillary muscles and mitral valves produced by vagal manipulations. In the 109 rabbits killed one week after clipping or crushing of their cervical vagi, papillary muscle and mitral valve lesions were found in 53 (48.6%) and 52 (47.7%) hearts respectively. The lesions were identified by visible deposits of colloidal carbon which had been injected intravenously during the first 3 postoperative days. The left ventricular free wall, interventricular septum and right ventricle were free of carbon deposits. The papillary muscles involved were characterized by swelling and increased stiffness which corresponded to degeneration of the myocardial cells and interstitial fibrosis on microscopic observation. Hydroxyproline content of the papillary muscles involved was 1.4 times more than that of normal hearts, while there was no significant difference in hydroxyproline content of either interventricular septum or left ventricular free wall between the manipulated and the normal preparations. Heart murmurs were heard in 23 animals studied. Phonocardiograms revealed mid to late systolic murmurs with or without midsystolic click. These results indicate that the vagus nerve plays an important role in the pathogenesis of some forms of papillary muscle and mitral valve lesions.

Animals↗

Left atrial enlargement in patients with paroxysmal atrial fibrillation.

The present study was designed to examine whether the left atrium is dilated in paroxysmal atrial fibrillation or not. Left atrial dimension (LAD) on M-mode echocardiogram was (1) 23.3 +/- 0.7 mm (mean +/- S.E.) in 24 normal subjects, (2) 30.5 +/- 0.7 mm in 58 patients without atrial fibrillation who had hypertension and/or ischemic heart disease, (3) 35.5 +/- 0.9 mm in 27 patients with paroxysmal atrial fibrillation of whom 23 had non-rheumatic cardiovascular diseases and 4 had idiopathic atrial fibrillation, (4) 40.5 +/- 1.1 mm in 38 patients with persistent atrial fibrillation of whom 30 had nonrheumatic cardiovascular diseases and 8 had idiopathic atrial fibrillation, and (5) 53.3 +/- 2.0 mm in 17 patients with persistent atrial fibrillation who had rheumatic heart disease. LAD showed a stepwise and significant increase from the first to the fifth group. LAD of patients with paroxysmal atrial fibrillation was not related to either the number or duration of paroxysms. These results indicate that the left atrium is slightly dilated in patients with paroxysmal atrial fibrillation.

Adult↗

Experimental production of poststenotic dilatation in the carotid arteries of rabbits.

Arterial dilatation distal to a stenosis has been known as poststenotic dilatation (PSD). This paper describes arterial constriction enough to produce PSD, time course of PSD, structural changes of the dilated segments and influence of hypertension on the development of PSD. These problems were studied in 2 experimental protocols. In protocol I, 87 carotid arteries of 45 rabbits were constricted by silver clip of 0.65 to 2.0 mm in diameter. The arterial diameter was measured at the sites both proximal and distal to the constriction after 3 days to 8 weeks. In protocol II, 22 carotid arteries of 12 rabbits with experimental one-or two-kidney Goldblatt hypertension were constricted and the development of PSD was compared with age matched controls. Remarkable PSD developed in arteries with moderate stenosis of 45 to 60% constriction. The degree of dilatation expressed as ratio of distal to proximal diameter reached about 1.5 at the end of the second week and remained unchanged thereafter. Destruction of the elastic fibers with intimal hyperplasia was observed in the dilated segments even at the early stages of the PSD. Both mild and severe stenosis failed to produce prominent PSD. In protocol II, the PSD averaged 1.18 +/- 0.05 (mean +/- SE) in hypertensive, and 1.32 +/- 0.03 in normotensive animals (p less than 0.05). The result suggests that chronic hypertension decreases the distensibility of the arteries.

Animals↗

Clinical features of paroxysmal atrial fibrillation. An observation of 94 patients.

During the past 10 years we experienced 234 patients with atrial fibrillation of whom 94 patients (40.2%) showed a paroxysmal form. Underlying diseases of these 94 patients were hypertension and/or coronary heart disease in 51 (54.3%), rheumatic valvular disease in 3 (3.2%), hyperthyroidism in 2 (2.1%), and miscellaneous diseases in 15 patients (16.0%). Idiopathic atrial fibrillation was found in the remaining 23 patients (24.5%). Frequency of paroxysm was variable. paroxysm occurred only once or twice in 35 patients (37.2%) and more than 21 times in 20 patients (21.3%). Duration of a single paroxysm ranged from less than 24 hours in 49 patients (52.1%) to more than 15 days in 7 patients (7.4%). Atrial fibrillation became permanent in 19 (25.3%) of 75 patients who had been observed for a period of more than 1 year.

Adult↗

Elevation of serum creatine phosphokinase during pindolol treatment.

We observed elevation of serum CPK in hypertensive patients under pindolol treatment. In this report, we showed a representative patient and compared serum CPK values in 56 patients under pindolol treatment to those in 64 patients under propranolol treatment. Mean serum CPK values in the patients under pindolol treatment and propranolol treatment were 117.0 +/- 12.6 (S.E.) and 50.8 +/- 3.8 IU/liter, respectively (p less than 0.01). Although the mechanism of elevation of serum CPK cannot be well understood, we should be careful in clinical evaluation of serum CPK during pindolol treatment.

Creatine Kinase↗