New upper limit of physiologic cardiac hypertrophy in Japanese participants in the 100-km ultramarathon

OBJECTIVES: The goal of our study was to define the structural characteristics of the heart in Japanese 100-km ultramarathon runners. BACKGROUND: During screening of participants in a 100-km ultramarathon, we found some participants who had larger cardiac chambers than had ever been previously reported. METHODS: A total of 291 male participants in a 100-km ultramarathon age from 20 to 73 years were examined using echocardiography. RESULTS: The mean heart rate (HR) was 50.6 +/- 5.6 beats/min (38 to 79 beats/min), the systolic blood pressure (SBP) was 110.5 +/- 5.6 mm Hg (94 to 138 mm Hg), the diastolic blood pressure (DBP) was 65.9 +/- 6.6 mm Hg (58 to 90 mm Hg), the left ventricular end-diastolic diameter (Dd) was 61.8 +/- 6.9 mm (42 to 75 mm), the left ventricular end-systolic diameter (Ds) was 39.6 +/- 6.0 mm (23.0 to 55.0 mm), the interventricular septal thickness (IVS) was 10.2 +/- 1.9 mm (5 to 19 mm), the posterior wall thickness (PW) was 10.0 +/- 1.4 mm (5 to 15 mm), the aortic diameter (Ao) was 38.5 +/- 4.0 mm (27 to 50 mm), the left atrial diameter (LA) was 40.2 +/- 4.8 mm (26 to 49 mm), and the systolic wall stress (WS) was 221.5 +/- 52.9 kdyne/cm(2) (108.0 to 537.6 kdyne/cm(2)). Significant predictors of these parameters were the monthly running distance for HR, SBP, DBP, Dd, Ds, Ao, LA, and WS, as well as the age for IVS, PW, and Ao. CONCLUSIONS: Thirty-three participants had a Dd larger than 70 mm. Moreover, some athletes had a larger aorta and left atrium than had ever been previously reported. The oldest runner was 73 years old.     

Dipole-tracing of abnormal slow brain potentials after cerebral stroke--EEG, PET, MRI correlations

A patient with major neurological deficits 5 years after a left cerebral infarction underwent correlative EEG, MRI and PET studies of cerebral blood flow and oxygen metabolism. The EEG showed abnormal slow electroencephalographic activity in the frontopolar region. The intracranial location of the slow electrical activity was estimated, as an equivalent current dipole, by using a newly developed dipole tracing (DT) method. The DT analysis showed that the dipole equivalent of the slow wave is approximately located at the frontal part of the left cingulate gyrus, away from the margins of the infarction and enlarged left lateral ventricle demonstrated by MRI, and in a region with intact oxygen consumption rate. The genesis of the slow wave is discussed.     

Equivalent dipole estimation of spontaneous EEG alpha activity: two-moving dipole approach

A method of estimating equivalent moving and fixed dipoles from the scalp-recorded EEG alpha waves, with the realistic geometry of the head taken into account, is presented. Twenty-one silver electrodes were used to collect spontaneous EEG alpha waves on the scale. Four models, the single-moving dipole model, the single-fixed dipole model, the two-moving dipole model and the two-fixed dipole model were applied to approximate the EEG alpha field on the scalp. The algorithm, based on a least-squares fit for estimating the moving and the fixed dipoles by using a realistically shaped head model, is described. The numerical accuracy of the algorithm is also evaluated by a computer simulation. It is found that the spontaneous EEG alpha activity observed on the scalp can be represented by two equivalent moving dipoles, simultaneously located separately in the occipital regions of the right and the left hemisphere, at a depth of 4–6 cm beneath the scalp, with a goodness-of-fit of up to 97 per cent for all subjects examined. The excellent fit of the two-moving dipole model to the EEG human alpha activity is also compared with the single-dipole fit.     

Lipoprotein analysis using agarose gel electrophoresis and differential staining of lipids.

We established a strategy to directly measure cholesterol and triglyceride levels of each lipoprotein fraction using a combination of agarose gel electrophoresis and differential staining. The cholesterol and triglyceride levels determined by electrophoresis correlated significantly with those of ultracentrifugation. The correlation coefficients between these methods were, for cholesterol levels 0.975(very low density lipoproteins, VLDL), 0.986(low density lipoproteins, LDL) and 0.965(high density lipoproteins, HDL) and for triglyceride levels 0.994(VLDL), 0.963(LDL) and 0.959(HDL) respectively. Both intra-and inter-assays showed low values of coefficients of variation (CV) (less than 3.57%). We observed a strong linearity between staining and triglyceride concentration. An increased VLDL-cholesterol was observed in type III subjects, a result which enabled distinction between type III and type IIb or type V lipoproteinemia. The method revealed lipoprotein patterns in some samples otherwise unexpected from their corresponding serum lipid parameters. Analyses of these electrophoretic patterns thus provide an effective technique to classify types of hyperlipidemia defined by the WHO. Furthermore, quantitative measurement of chylomicrons, usually difficult, proved to be achievable, providing an additional analysis of postprandial hyperlipidemia and the exact measurement of LDL-cholesterol after diet. Consequently, we recommend this simple and easy method for clinical evaluation of abnormalities in lipoprotein profiles.     

Plasma brain natriuretic peptide in takotsubo cardiomyopathy

BACKGROUND: Takotsubo cardiomyopathy is a reversible left ventricular dysfunction with symptoms resembling acute myocardial infarction, but without coronary lesions. Patients have wall motion abnormalities (apical akinesis and basal hyperkinesis), and characteristic left ventricular morphology. AIM: To investigate plasma brain natriuretic peptide (BNP) concentrations in takotsubo cardiomyopathy. METHODS: Ten consecutive patients with takotsubo cardiomyopathy underwent cardiac catheterization on their first hospital day, and blood was collected to measure BNP. To evaluate acute basal hyperkinesis, the difference in diameter between systole and diastole was measured at 10 mm below the aortic valve (the deltaBase value). RESULTS: Coronary angiography revealed no significant stenosis in any patient. Initial ejection fraction was 42.2 +/- 7.3%, cardiac index was 1.90 +/- 0.39 l/min/m(2), and plasma BNP was 522.5 +/- 632.9 pg/ml. Ventricular contraction and the ejection fraction were normalized on echocardiography after 17.9 +/- 6.3 days. BNP was significantly correlated with deltaBase, but not with other cardiac parameters. DISCUSSION: Initial deltaBase value seems to be a good indicator of the severity of basal hyperkinesis in patients with takotsubo cardiomyopathy. In contrast to other diagnoses, a high BNP concentration is not associated with a poor prognosis in this condition.     

Etiological study of spinal ligament ossification with special reference to dietary habits and serum sex hormones

We studied the relationship between dietary habits and the ossification of the posterior longitudinal ligaments (OPLL) in 55 patients. We analyzed carbon and nitrogen isotope ratios of the patients' hair in order to measure the intake of various types of food. Two sets of questionnaire on the patients' food preference and the intake are also analyzed. The patients showed a tendency to prefer vegetable protein to animal protein, in comparison with the control. In 23 OPLL male patients, level of the estrogen in the serum was higher than in the control. The results suggest that the dietary habits of OPLL patients and the sex hormone imbalance are responsible for the development of OPLL.     

Estimation of the rising phase of EPSP analyzed by computer simulation of the coding process

Based on data obtained from intracellular recordings of cat alpha-motoneurons in the stretch reflex, the firing process of these motoneurons was computer-simulated. The impulse response EPSP (IR-EPSP) was simulated to correspond to a monosynaptic mass EPSP elicited by a spindle afferent volley, while the returning potential was simulated to correspond to a potential gradient rising toward an augmenting depolarization of the membrane (augmentative EPSP) after motoneuronal spike generation. The IR-EPSPs were generated by input at random intervals and added to each other, linearly, on the returning potential. As soon as the resultant potential attained the critical threshold level, V_th, motoneuron firing occurred. Then IR-EPSPs were again added to the returning potential until another motoneuron firing occurred. This process was repeated continuously, and the time relation between input and output, lag-time distribution (P_T(T)), was determined Distribution of the bias potential, P_V(v), from which the motoneuron spike triggering EPSP started to rise, was also calculated. The relations between P_T(T), P_V(v) and a waveform of the IR-EPSP were obtained analytically. The relation indicated that the shape of P_T(T) corresponds to a time derivative of the rising phase of the IR-EPSP if the P_V(v) distribution is uniform. In this study, we investigated the possibility of making the P_V(v) distribution uniform.     

Studies on nicotinic acid interaction with bilirubin metabolism

The mechanism by which intravenous administration of nicotinic acid (NA) increases serum unconjugated bilirubin in patients with the Gilbert's syndrome has been investigated. Studies using the technique of percutaneous transhepatic catheterization of the splenic vein and coil planet centrifuge suggested that following intravenous injection of NA some of the circulating erythrocytes were rendered osmotically fragile and trapped by the spleen and that unconjugated bilirubin increased in the splenic vein blood. In patients with liver cirrhosis, the increments of unconjugated bilirubin were closely correlated with the weights of the spleens removed for the management of varices. In rats, intravenous NA injection enhanced heme oxygenase activities in the spleen, but not uridine-5-diphosphate (UDP)-glucuronyltransferase activity in the liver. These results are consistent with the hypothesis that NA-induced unconjugated hyperbilirubinemia is a result of complex reactions which include increased erythrocyte fragility, increased splenic heme oxygenase activity, and increased formation of bilirubin in the spleen.     

Cruveilhier-Baumgarten syndrome presenting with precordial murmur and thrill

Summary A 47-year-old male who presented with a huge spleen and a loud continuous murmur with palpable thrill over the sternum is described. He had had several episodes of massive hematemesis prior to admission, and a traumatic arteriovenous fistula was suspected because of the past history of a blow over the left flank. Celiac arteriography was not diagnostic. Percutaneous transhepatic portography demonstrated a large collateral vein arising from the left portal branch and coursing behind the sternum.