In order to evaluate the correlation between sulfur amino acids (derived mainly form animal protein in the diet) and blood pressure, free amino acids, including sulfur amino acids such as taurine and methionine, were determined in the plasma and cerebrospinal fluid (CSF) of twelve normotensive subjects and twelve patients with essential hypertension under nutritional control after at least 10 days of standard hospital diet (total calorie and protein content: 2100-2300 Cal per day and 78-83g per day, respectively). The results obtained were as follows: plasma taurine, serine, methionine and threonine were significantly lower in patients with essential hypertension than in normotensive patients. The levels of plasma taurine, serine, methionine and total sulfur amino acids in individuals correlated inversely to systolic blood pressure. No difference was observed in the CSF levels of free amino acids in normotensive and hypertensive patients. As taurine, methionine and serine are involved in the metabolism of sulfur amino acids, these observations support the view that the decrease in plasma sulfur amino acids may be a factor contributing to elevated blood pressure.

View full abstract

To make a comparison of two exponential models of the time constant (Tw: Weiss's ;method, Tc: exponential analysis with a variable asymptote) during left ventricular (LV) isovolumic relaxation, we assessed LV pressure decay in 104 patients with coronary artery disease (CADpts) and 21 normal subjects at rest and after pacing, and investigated the hemodynamic determinants of these two models using forward-backward stepwise multiple regression analysis. At rest, Tw was prolonged as the left ventricular minimal pressure (LVPmin), the left ventricular end-diastolic pressure (LVEDP) and the end-systolic volume (ESV) increased (multiple regression coefficient: R=0.87), whereas Tc was prolonged as ESV and regional wall motion abnormality (RWMA) increased (R=0.72). Pacing-induced changed in Tw were augmented as LVPmin and RWMA increased (R=0.75), whereas changes in Tc were augmented as RWMA increased (R=0.63). Thus, the changes in Tw may be due to an increase in LVPmin rather than to any direct effect of ischemia on the relaxation rate. the relaxation rate can be evaluated more reliably by Tc than by Tw, irrespective of associated pressure changes during ischemia in CADpts.

View full abstract

This study was designed to clarify the mechanism of reperfusion arrhythmia and with the effect of verapamil on arrhythmia. In vivo study Fifth anesthetized dogs were divided into two groups the control group (n=37) and the verapamil group (n=13). The left anterior descending coronary artery (LAD) was occluded for 15 min and then reperfused for 5 min. Physiological saline or verapamil (0.4 mg/kg) was infused 5 min prior to the LAD reperfusion. Eleven (30%) of the control dogs developed "reperfusion arrhythmia" (arrhythmia group) but 26 did not (non-arrhythmia group), while in the verapamil group, none of the 13 dogs developed arrhythmia. Immediately after 5 min reperfusion, myocardial plasma membrane and mitochondria were prepared from the normal and the reperfused area. In the arrhythmia group, an increase in free fatty acids (FFA) and a decrease in phospholipids were observed in membrane samples, and the content of calcium in the mitochondria increased in the reperfused myocardium; these changes were not observed in the non-arrhythmia group or the verapamil group. In vitro study In vitro study consisted of two experiments. In experiment 1, incubation of myocardial plasma membrane with phospholipase (PLase) A₂ increased only the unsaturated FFA, while PLase C increased all the detected FFA. In experiment 2, the effects on myocardial membrane potentials induced by PLase A₂ and PLase C were studied by using microelectrodes. Each PLase caused a decrease in the resting potential and in the magitude and duration of the action potential. These results and the fact that Ca²⁺ is the essential factor which activates PLase suggest that the activation of PLase, triggered by Ca²⁺ influx associated with reperfusion, develops the arrhythmogenic conditions, and that the protective effect of verapamil is based on inhibiting the activation of PLases by interfering with Ca⁺⁺ influx.

View full abstract

The role of phospholipase (PLase) on the mechanism of the so called "down regulation", which decreases the number of β-adrenergic receptors (β-AR) of rat cardiac membranes during successive β-agonist administration, was investigated. In vivo study: The rats were divided into 3 groups; (1) the control group, untreated; (2) the isoproterenol (ISP) one day group, ISP (10 mg/kg) was subcutaneously injected once; and (3) the ISP 6 days group, ISP (10 mg/kg) was injected once a day for 6 successive days. Binding assay using [³H] dihydroalprenolol and analysis of the content and the composition of fatty acids in phospholipids in cardiac membranes were conducted. The endogenous PLase activity in heart homogenate and tissue ATP levels were also determined. In the 6 days group, the equilibrium dissociation constant of β-AR was not affected; however the number of β-AR decreased significantly when compared with the control group. Phospholipid content also decreased in parallel with the decrease in the number of β-AR and the composition of fatty acids was altered. However, in the one day group, there were no significant changes in either the number of -AR or the phospholipid content. The PLase activity of heart homogenate increased significantly, and the tissue ATP levels decreased in both the one day and the 6 days group. In vitro study: Cardiac membranes prepared from intact rats were incubated with 0.03 and 0.1 unit of PLase A₂. PLase A₂ reduced the number of -AR dose-dependently. These results suggested that the degradation of membrane phospholipids caused by persistent activation of endogenous PLase is closely related to the decrease in the number of -AR during successive administration of -agonist.

View full abstract

Studies on the prevalence of beta-hemolytic streptococci in throats among primary school children were performed in Otsu City. In the first study, evidence of streptococcal infections was investigated in 41373 children of first grade of all primary schools for the 13 years from 1970 to 1982. An average of 12.2% of the strains isolated belonged to group A. the order of frequency of the other Groups was B, C and G respectively. The most predominant type of Group A streptococci was Type 12. In the second study, evidence of streptococcal infections was investigated in 87 children of the first grade of one primary school for the 5 years from 1977 to 1982. Throat cultures were repeated four times a year during the period of five years. Entire negative throat cultures over a 5-years period were observed in only 4 children. The prevalence of beta-hemolytic streptococci and Group A streptococci in throats were higher than those observed in the first study. The predominant types of Group A were Types 1, 6 and 28, although the relative predominance of these Types varied at different times during 5 years. High serum ASO titers were observed in the children who harbored Type 6 strains of Group A streptococci in throats. In 5 children Group A streptococci were frequently recovered from throats during the study period, and the same type of strains of Group A streptococci were isolated repeatedly.

View full abstract

From the clinical signs and symptoms of 145 cases of streptococcal pharyngitis and 126 cases of non-streptococcal pharyngitis, a new scoring system for diagnosis of streptococcal pharyngitis was devised. Efficacy of diagnosis for streptopharyngits by this method was 54% if a case had 5 items, 75% if he had 6 items and 93% if he had more than 7 items respectively.

View full abstract

In hemolytic streptococcal infection, a high ASE value in the absence of a rise in ASO has shown to occasionally occur. The relationship between ASO and ASE titers in rheumatic fever and rheumatic heart disease and the significance of these values was therefore studied. ASE values were measured by ASE Kit "Marupi" in 8 patients during the acute stage of rheumatic fever and in 9 patients with rheumatic heart disease, and then compared with the corresponding ASO values. Among the patients with rheumatic fever, a rise of ASO only was seen in 1 patient and a rise of ASE only was seen in another., In the remaining 6 patients, both ASE and ASO were elevated. Only in 1 patient with rheumatic heart disease was ASE found to be elevated.

View full abstract

Wistar rats were administered M-protein fraction (MP) of group A type 12 hemolytic streptococci on day 9 of gestation. When 9 mg/kg of MP was injected, the incidence of malformations was 11.8%, and the incidence of cardiovascular malformations was 7.9%. The main malformations were ventricular septal defect, microphthalmia, and hydrocephaly. Light and electron microscopic studies revealed no myocarditis nor endocarditis in either the maternal or fetal heart. Fluorescent antibody technique demonstrated no immunological cross-reaction between MP and rat heart tissue. the results suggest that MP is slightly teratogenic in the rat.

View full abstract

In order to determine the characteristics of the interstitial fibrotic change of the myocardium in cases with viral or idiopathic myocarditis, right ventricular endomyocardial biopsy findings in 9 cases where serial endomyocardial biopsy had been performed at the acute (5-10 days after the onset of the disease), subacute (11-21 days) and convalescent stages (22-167 days) and in 1 case at the acute stage were analyzed. They were then compared with right ventricular endomyocardial biopsy findings from 58 cases with chronic right ventricular overloading and which were of various kinds of congenital and valvular heart diseases. The following results were obtained: 1)Interstitial fibrosis was seen at the acute stage along with an increase in fibroblasts, macrophages and lymphocytes. 2) An analysis of the interstitial changes revealed that, at the acute stage, thin collagenous fibers were prominent as well as interstitial edema and at the convalescent stage, the edema became less prominent and instead, thick collagenous fibers increased. 3) comparison with the 58 cases with chronic right ventricular overloading revealed that diffuse and/or subendocardial fibrosis and endocardial thickening were more frequent and statistically more significant in cases with myocarditis.

View full abstract

In an investigation of the relationship between mural thrombosis and congestive heart failure (CHF) in acute viral myocarditis, inbred BALB/c mice were inoculated intraperitoneally with the M variant of encephalomyocarditis (EMC) virus and sacrificed on days 7(n=33), 10(n=35) and 14(n=39). Myocarditis was found in 105 of 107 sacrificed mice (98.1%). Myocardial necrosis with cellular infiltration was evident after day 7 and was extensive in the ventricles and atria. In the 105 mice with myocarditis, 17 mice (16.2%) developed CHF after day 10, and 15 mice (14.3%) had thrombi as early as day 7. All thrombi were in the left and/or right atrium. The incidence of thrombi in mice with CHF was higher, but not significantly so, than that in mice without CHF (23.5% vs 12.5%). All 50 control mice had no myocardial lesions or thrombi. This study demonstrates that thrombus formation was not rare in the absence of CHF in the acute stage of viral myocarditis and suggests that clinically acute viral myocarditis has a risk of systemic and/or pulmonary embolism even when resting cardiac function is normal.

View full abstract

In 1981, a mass survey for Kawasaki disease was performed in Shimane Prefecture. The incidence of the disease was 0.3% in elementary and 0.1% in junior high schools, respectively. The number of children with a past history of Kawasaki disease was 40. Selective coronary arteriography (S-CAG) was performed on 37 children by December 1983 and 3 cases having coronary lesions were detected. In all these 3 children, more than 8 years had elapsed since the onset of the disease and in one of them there were severe stenotic changes in the coronary artery, with coexisting mitral incompetence. Two-dimensional echocardiography (2D echo) was able to detect dilatatory coronary lesions, but it failed to delineate stenotic changes adequately in these 3 cases. The present data indicate that 2D echo cannot demonstrate the stenotic segments of the coronary artery and therefore S-CAG is necessary for that purpose. We suggest coronary arteriography (CAG) for school children with a past history of Kawasaki disease.

View full abstract

Transmural conduction velosity index (TCVI) was obtained in 174 healthy children. TCVI was defined as the echocardiographically determined interventricular septal thickness (IVST) devided by the ventricular activation time (VAT) measured by body surface potential mapping. TCVI ranged from 14 to 49 cm/sec and was highly correlated with IVST (r=0.75, TCVI=3.25x IVST+0.56). It was concluded that the left ventricular hypertrophy with muscular thickness does cause the greater conduction velosity in healthy children.

View full abstract

Seventeen healthy children with QS-pattern in lead V1 were studied vector-cardiographycally. Age ranged from 6 to 15 years old. Azimuth at 10 and 20 msec displaced leftward an azimuth of maximum spatial voltage slightly displaced posteriorly. Anterior component was minimal. QS-pattern in lead V1 in children is not necessarily abnormal finding. The main cause of QS-pattern in lead V1 is electrical rotation of the heart.

View full abstract

Long-term ambulatory electrocardiography was utilized in a heart disease screening system for elementary school children and junior and senior high school students in Nagoya, Japan. The elementary school children, and junior and senior high school students who have serious arrhythmias or potential risk of syncope and sudden death are the subjects of ambulatory monitoring. Of 42 school children and students taking ambulatory electrocardiography for frequent ventricular premature contractions, 8 had Lown's grade 4A, 4B or 5. The cases with third-degree AV block showed ventricular tachycardia or frequent ventricular premature contractions during exercise in ambulatory electrocardiograms. These complex ventricular arrhythmias are possible risk factors of sudden death. It has been proved that ambulatory monitoring is beneficial in the screening and management of serious arrhythmias in the heart disease screening system.

View full abstract

One thousand and twenty-two of senior high school students and 274 of primary and junior high school students screened as positive through heart disease mass examination were tested by the Master's two step Method. The results are as follow: 1) In order to get informations to give the guide line for school life, it is still insufficient triple amounts of exercise performed during 3 minutes and 45 seconds for high schoolmate students although this may be appropriate for primary, junior high school students and female senior high school students. 2) Fatigue and their history concerning to athletic activity should not be neglected to evaluate the results of exercise test. 3) It is important to consider before valuation of the test that QTc immediately after exercise shorten by 6 to 8% and QTc 3 minutes after the exercise prolonged by 3 to 4%.

View full abstract

In order to elucidate fundamental relationship between exercise and cardiac reserve, we investigated the parameters of regression equation (VO₂=A·HR+B) between oxygen consumption (VO₂ ml/kg/min) and heart rate (HR) during exercise test (Bruce). 62 male children were devided into 3 groups based on history and clinical evaluation. HR related linearly with VO₂ (average r=0.967, range 0.900.993). both of the parameters A and |B| were significantly high in Athlete (A=0.465±0.043, |B|=36±6.07), low in Failed (0.297±0.055, 17.4±6.1) and middle in Ordinary group (0.366±0.078, 23.5±8.6) (p<0.005). Based on our result of linear VO₂-HR relation, and on the previously reported studies that cardiac output linearly and consistently related with VO₂, we considered the meaning of the parameters as follows; A determines the possible maximum stroke volume (SV), and B determines the HR where SV reaches plateau. In conclusion, since the SV is considered as a ;measure of cardiac function, measureing the parameters of VO₂-HR relation allows us to isolate cardiac functional reserve through the exercise tolerance test.

View full abstract

Incidence of mitral valve prolapse (MVP) in 4517 students of Kobe University, and clinical features in cases with MVP were studied. MVP was detected in 42 cases by two-dimensional echocardiography, and the prevalence of MVP was 0.93 percent (42 of 4517 cases). Among 42 cases with MVP, apparent mitral regurgitation (MR) was noted in one case with severe MVP, ventricular tachycardia was detected in one and ST-T wave abnormalities were detected in 10 respectively. In another follow up study of our hospital, 14 of 85 patients followed more than one year were noted to be deterioration in echocardiographic parameters. Eight of 14 patients had severe prolapse with severe MR, but remaining 6 had mild or moderate prolapse with mild or absent of MR. However, ST-T wave abnormalities, serious arrhythmias, and low response of %FS increase on exercise were found in high incidence in 6 of mild or moderate prolapse as well as in severe prolapse. So these follow up results suggested that only only students with severe MVP but also students with mild or moderate MVP with ST-T wave changes or VPC found in university medical examination must be followed up carefully.

View full abstract