Hidden peculiar magnetic anisotropy at the interface in a ferromagnetic perovskite-oxide heterostructure.

Understanding and controlling the interfacial magnetic properties of ferromagnetic thin films are crucial for spintronic device applications. However, using conventional magnetometry, it is difficult to detect them separately from the bulk properties. Here, by utilizing tunneling anisotropic magnetoresistance in a single-barrier heterostructure composed of La0.6Sr0.4MnO3 (LSMO)/LaAlO3 (LAO)/Nb-doped SrTiO3 (001), we reveal the presence of a peculiar strong two-fold magnetic anisotropy (MA) along the [110]c direction at the LSMO/LAO interface, which is not observed in bulk LSMO. This MA shows unknown behavior that the easy magnetization axis rotates by 90° at an energy of 0.2 eV below the Fermi level in LSMO. We attribute this phenomenon to the transition between the e g and t 2g bands at the LSMO interface. Our finding and approach to understanding the energy dependence of the MA demonstrate a new possibility of efficient control of the interfacial magnetic properties by controlling the band structures of oxide heterostructures.

Classification and assessment of computerized diagnostic criteria for Brugada-type electrocardiograms.

BACKGROUND: Although a Brugada-type electrocardiogram (ECG) is occasionally detected in mass health screening examinations in apparently healthy individuals, the automatic computerized diagnostic criteria for Brugada-type ECGs have not been established. OBJECTIVE: This study was performed to establish the criteria for the computerized diagnosis of Brugada-type ECGs and to evaluate their diagnostic accuracy. METHODS: We examined the ECG parameters in leads V1 to V3 in patients with Brugada syndrome and cases with right bundle branch block. Based on the above parameters, we classified the ECGs into 3 types of Brugada-type ECGs, and the conditions for defining each type were explored as the diagnostic criteria. The diagnostic effectiveness of the proposed criteria was assessed using 548 ECGs from 49 cases with Brugada-type ECGs and the recordings from 192,673 cases (36,674 adults and 155,999 school children) obtained from their annual health examinations. RESULTS: The Brugada-type ST-segment elevation in V1 to V3 was classified into 3 types, types 1, 2/3, and a suggestive Brugada ECG (type S). The automatic diagnostic criteria for each type were established by the J-point amplitude, ST-segment elevation with its amplitude and configuration, as well as the T-wave morphology in leads V1 to V3. CONCLUSION: The proposed criteria demonstrated a reasonable accuracy (type 1: 91.9%, type 2/3: 86.2%, type S: 76.2%) for diagnosing Brugada-type ECG in comparison to the macroscopic diagnosis by experienced observers. Moreover, the automatic criteria had a comparable detection rate (0.6% in adults, 0.16% in children) of Brugada-type ECGs to the macroscopic inspection in the health screening examinations.

Automated detection of Brugada-type electrocardiogram using diagnostic criteria of the European Society of Cardiology and the American Heart Association.

The diagnostic criteria of Brugada syndrome were reported from the European Society of Cardiology (ESC) and the American Heart Association in 2002. We examined the automated detection of Brugada-type electrocardiogram (ECG) on 12-lead ECG analysis program by modifying ESC criteria and evaluated it. In ESC criteria, Brugada-type ECG was classified into 3 types of ST-segment abnormalities of V1 to V3 leads. We modified these criteria and determined automated detection criteria as follows: type 1: STj>or=0.2 mV and STj>ST1>ST2 and T<0 mV; type 2: STj>or=0.2 mV and STj>STmin>or=0.1 mV and T>0 mV and T<1.8xR' and Sor=0.2 mV and 0.1 mV>STmin>0 mV and T>0 mV and T<1.8xR' and S>or=3.0 mV; STj, ST1, and ST2 are amplitude of the ST segment (STj: J point, ST1: J point +40 milliseconds, ST2: J point +80 milliseconds). We evaluated these criteria with 97 ECGs from 27 patients, which are diagnosed as Brugada syndrome in university hospital. Brugada-type ECGs were detected correctly in 85 of total 97 ECGs (sensitivity, 88.7%, type 1: 32/32, type 2: 50/61, type 3: 4/4). As compared with 5 cardiologists interpretation of Brugada-type ECGs, computer classified incorrectly in 20 ECGs (type 1: 2, type 2: 17, type 3: 1) in 21,524 cases.

QT dispersion correlates with systolic rather than diastolic parameters in patients receiving anthracycline treatment.

OBJECTIVE: The aim of this study was to investigate the relation of QT dispersion to left ventricular (LV) systolic and diastolic function in patients undergoing anthracycline therapy. METHODS: We used echocardiography to evaluate LV systolic and diastolic function and electrocardiography to evaluate QT dispersion and corrected QT dispersion (QTcD) in patients with hematological diseases, who received anthracycline therapy. PATIENTS: Seventy-two patients with hematological diseases who were receiving anthracycline treatment were enrolled in the present study. RESULTS: LV end-diastolic diameter or LV end-systolic diameter had a significant positive correlation to QTcD (r = 0.35, p < 0.01, r = 0.43, p < 0.01). Also left ventricular ejection fraction of (LVEF) or fractional shortening had a significant negative correlation to QTcD (r = -0.46, p < 0.001, r = -0.27, p = 0.02). The highest QTcD group had a significantly larger LV end-diastolic diameter or LV end-systolic diameter than the lowest QTcD [48.5 +/- 5.7 vs. 44.4 +/- 4.5 (mm), p < 0.001, 34.1 +/- 6.4 vs. 28.8 +/- 4.3 (mm), p < 0.001] and the highest QTcD group had a significantly lower LVEF than the lowest QTcD [57.5 +/- 8.0 vs. 65.5 +/- 6.4 (%), p < 0.001]. On the other hand, none of the diastolic function markers were significantly correlated with QTcD. CONCLUSION: We concluded that increased QTcD is correlated with LV dilation and systolic dysfunction induced by anthracycline therapy, and does not reflect a dispersion of ventricular repolarization or asynchronous motion.

Gender and age differences in lifestyle factors related to hypertension in middle-aged civil service employees.

The aim of this study is to identify lifestyle factors related to hypertension in man and woman workers, and to investigate age and gender differences in the relationships of the factors. From 6,000 civil service employees (4,937 men and 1,063 women) aged 40-69 years, information on lifestyle-related factors such as stress, exercise habits, preference for salty taste, alcohol drinking and smoking habits, and body mass index, as well as age and family history of hypertension was obtained through self-administered questionnaires in 1997. Hypertension was defined as either a systolic blood pressure > or = 140 mmHg, a diastolic blood pressure > or = 90 mmHg, or undergoing treatment for hypertension, and was present by 37.0% in men and 19.6% in women. Only body mass index was a significant lifestyle-related risk factor common to both genders with an odds ratio and its 95% confidence interval in parentheses of 2.2 (2.0-2.5) for men and 3.2 (2.3-4.6) for women. Men and women who preferred salty taste showed multivariate adjusted odds ratios of 0.9 (0.8-1.1) and 1.5 (1.1-2.2) for hypertension, respectively. In the stratified subanalysis, women aged 50 years and over had a significant odds ratio of 2.7 (1.5-4.9), whereas women aged 40-49 years and men of all age classes failed to show significant relationships. Salt intake was suggested to be a key factor for hypertension particularly for women after menopause.