Multivariate analysis of TU wave complex on electrocardiogram in Andersen-Tawil syndrome with KCNJ2 mutations.

BACKGROUND: The exact differences between the TU wave complex of ATS1 and that of healthy individuals remain to be investigated. We sought to characterize the TU wave complex of Andersen-Tawil syndrome type 1 (ATS1) using high frequency electrocardiogram (ECG) data. METHODS: Electrocardiograms were recorded as time series data with a 2 kHz frequency ECG amplifier in 13 patients with ATS1 (positive for KCNJ2 mutation, ATS1 group) and age-matched healthy individuals (control group). Conventional ECG parameters were measured, and principal component analysis (PCA) and independent component analysis (ICA) were applied to the TU wave complex. RESULTS: Time from T peak (Tp) to U peak (Up), time from bottom (B) to Up, and time from B to U end (BUe, U duration) (0.232 ± 0.018 vs. 0.165 ± 0.017, p < .0001), where B is the lowest point between T and U waves, were all longer in the ATS1 group than the control group. Multivariate logistic regression analysis revealed that BUe could completely differentiate the two groups. PCA ratios in the ATS1 group were significantly larger than the control group (26.5 ± 12.3 vs. 10.4 ± 6.2, p = .0005). ICA revealed 1 or 2 U-wave-specific independent components (ICs) that exclusively comprise the U wave in ATS1, whereas U waves in the control group were composed of some ICs that also comprised T waves. CONCLUSIONS: U-wave-related temporal parameters, particularly BUe, and the existence of U-wave-specific ICs, extracted in the ICA, are useful for differentiation of U waves in ATS1 from those in healthy individuals.

[Epidemiological analysis and clinical study of pediatric human metapneumovirus detected in patients with acute respiratory infection].

We detected and isolated human metapneumovirus (HMPV) and isolated another respiratory virus in pharyngeal swab specimens from 502 pediatric patients with acute respiratory infection, seen at 3 Kyoto City sentinel hospitals from January to December 2011. Our prospective study detected 43 positive HMPV cases (8.6%). Phylogenetic analysis showed that subgroup A2 was most common, followed by B1 and B2, and that A1 was not detected. HMPV was detected mostly in specimens from patients less than 3 years old, and positive HMPV was identified most in spring, peaking in March. Our clinical study showed that positive HMPV patients had fever above 38 degrees (86%) and cough (65%). Among the 30 whose chest radiography was examined, radiological findings were recognized in 18 cases. We found inflammatory infiltrative shadows around the bronchus and peribronchus near the hilum of the lung. Lobar pneumonia and diffuse infiltrative shadows coinciding with peripheral alveolar involvement were not recognized. No difference affecting illness severity was seen among subgroups, viral isolation results, or mixed coxsackie virus or influenza virus infection. In hospitalization, mean disease lasted significantly longer in those with lower respiratory tract symptoms at first'examination than in those without such symptoms. We detected HMPV RNA in pharyngeal swabs and stool specimens from patients admitted to the hospital for rhabdomyolysis.

Analysis of the shape of the T-wave in congenital long-QT syndrome type 3 by geometric morphometrics.

The characteristic shape of the T-wave in congenital long-QT syndrome type 3 (LQTS3) is considered a late-onset T-wave. We analyzed the difference in the shapes of the T-waves of V5 in the electrocardiograms (ECGs) of LQTS3 cases and normal subjects using generalized Procrustes analysis. The J and Q points of LQTS3 cases are shifted to the upper left compared to those of normal subjects. SdFmax is the point on the ECG where the second derivative is first maximized. SdFmax is the point where the change in the slope of the ascending limb of the T-wave is maximized. SdFmax in LQTS3 cases is shifted to the lower right compared to normal subjects. The interval from J to SdFmax in LQTS3 cases is expanded compared with that of normal subjects. From principal component analysis of the Procrustes mean shape of the T-wave landmarks, the second principal component shows a shift of SdFmax to the lower right. These results can quantitatively explain why the T-wave of LQTS3 cases looks like a late-onset T-wave. After being fitted to a multivariate logistic regression model, LQTS3 cases and normal subjects can be distinguished by the second independent component.

[Norovirus infection outbreaks in Kyoto City--2006-2007].

We studied 96 mass outbreaks of infectious gastroenteritis due to Norovirus in winter 2006-2007. Of these, 56 occurred in welfare institutions for aging adults 31 in hospitals, and 9 in other facilities such as kinder gardens. Affected staff accounted for 25.9% and users (inpatients, etc.) for 74.1%. The shortest outbreak lasted 10 days and the longest 67 days. We found a positive corelation between periods from the beginning of an outbreak to warnings by public health centers and periods from the beginning to the end of outbreaks. The sooner advice was aired by public health centers, the sooner outbreaks ended. Dementia among users and insufficient knowledge and skills of staff were high risk factors in outbreaks. All 74 of specimens which we examined showed the GII4 genotype. We observed reoutbreaks at three institutions. We compared first and second specimens from the same institution. Two specimens from the second outbreak belonged to the same cluster as the first outbreak. We analyzed 310 bases of RT-PCR products in Capsid regions in both specimens, finding three point mutations accompanied by amino acids changes. This may change the antigenicity of Capsid protein, and may be why reoutbreaks occurred so quickly.

Characterization of latex particles for aqueous polymeric coating by electroacoustic method.

Concentrated dispersions are used as coating dispersions for aqueous polymeric coatings, and characterization of the actual concentrated dispersions is an important in the pharmaceutical industry. The commonly used aqueous coating polymers are acrylic polymers and cellulose derivatives. We conducted a characterization study of polymethacrylate-based aqueous polymeric latex for aqueous coating, Eudragit L30D-55 (A-latex) and Eudragit RL30D (C-latex), by electroacoustic method. Colloidal Vibration Current (CVI) is one of the most important parameters relating to dynamic electrophoretic mobility and zeta potential, so we evaluated this parameter first. Volume fractions var of the latex in concentrated dispersions affect the CVIs according to the theory of Dukhin et al. The A-latex and C-latex CVI(*)s which were corrected with regard to the effect of volume fraction by the theoretical equation were nearly constant independent of phi in the ranges >0.04 and >0.03, respectively. The zeta potentials and colloidal stabilities of the concentrated dispersions were evaluated using an electroacoustic method by altering the pH and salt concentration. A-latex strongly aggregated at and below pH 2.5 and at and beyond 0.06 mol/L of electrolyte concentration. Regarding C-latex, instable dispersion was observed at 0.3 and 1 mol/L of NaCl concentration. The total potential energy of interaction between pairs of latex particles was changed by altering the salt concentration in this dispersion based on DLVO theory. The experimental results of stability in the concentrated latex dispersions can be explained by the total interaction energies.

Colloidal stability of aqueous polymeric dispersions: effect of water insoluble excipients.

An important issue in the aqueous coating process is dispersion stability. An unstable dispersion results in aggregation of the colloidal particles, thereby affecting the film coating process. In the coating suspension containing pigment, a latex for aqueous film coating might interact with pigment, resulting in unstable dispersion. We therefore conducted a stability investigation in a mixed dispersion including latexes, EudragitL30D-55 (A-latex), EudragitRL30D (C-latex) and EudragitNE30D (N-latex) and pigments, titanium dioxide and iron oxide yellow. An aggregation of the dispersion containing A-latex was observed at pH 2. Regarding the dispersions with C-latex and N-latex, no aggregation was observed in the range pH 2-11. We calculated total interaction energy between latex-latex particles, pigment-pigment particles and latex-pigment particles based on DLVO theory. The calculated results explained two mechanisms of the stable mixed dispersion. The first was that the individual latex particle and the pigment particle dispersed without aggregation in the mixed dispersion because of the electrostatic interaction. The next was that the latexes adsorbed onto the surface of the pigments, making electrostatically stable heterocoaggregates. We also calculated the binding constant of iron oxide yellow for C-latex at pH 10. The value of the constant was determined to be 1.1 x 10(-2).

Colloidal stability of aqueous polymeric dispersions: effect of pH and salt concentration.

Aqueous film coatings often contain some electrolytes, organic acids, and pigments to give functions of sustained release, time-controlled release, or protection against light. Additions of some electrolytes or organic acids into latex dispersion for an aqueous film coating affect its colloidal stability. We characterized the aqueous polymeric latexes used in the pharmaceutical industry by measuring zeta potential and particle size, and evaluated this colloidal stability using DLVO theory. Three polymethacrylate-based aqueous polymeric latexes, Eudragit L30D-55, Eudragit RS30D and Eudragit NE30D, having anionic, cationic, and neutral polymer, respectively, were used in this study. The Hamaker constant of the polymethacrylate-based latex was determined to be 6.35 x 10(-21) J, and the total potential energy of the latex dispersion was calculated. The total potential energy of interaction between pairs of latex particles changes by altering the salt concentration and pH. The experimental results of stability in the anionic and the cationic latex dispersions can be explained by the total interaction energies. However, the stabilization of the neutral latex did not match the calculated result. The steric interaction produced by the surfactant likely resulted in the stable dispersion of this latex.

Late-onset familial amyloid polyneuropathy: an autopsy study of two Japanese brothers.

We report an autopsy study of late-onset familial amyloid polyneuropathy with a variant transthyretin Val30Met in 2 brothers living in Kyoto, Japan. The disease onsets were at 64 and 59 years, and they died at 71 and 74 years old, respectively. They exhibited almost the same postmortem findings. Amyloid deposition was remarkable in the hearts, but was not seen in the renal glomeruli. In the peripheral nervous system, amyloid deposition was most prominent in the nerves immediately caudal to ganglia, moderate in the dorsal and sympathetic ganglia, and mild in the spinal roots, sciatic nerves, and distal nerves. The difference between the amyloid deposition in the proximal portion and distal portion of the extremity nerves appeared to be greater in the late-onset type than in the ordinary type, and this proximal deposition of amyloid may have induced severe distal nerve fiber degeneration.

The fetal electrocardiogram by independent component analysis and wavelets.

Once the fetal electrocardiogram (FECG) waveforms from ECG on the maternal abdomen are detected, the fetal P wave and T wave cannot always be identified by using continuous wavelet transform (CWT). We took noninvasive FECG from the maternal abdomen, extracted it from the maternal electrocardiogram waveforms after an Independent Component Analysis (ICA), and identified the features of those waveforms by using CWT. We also simultaneously analyzed the observed signals by Primary Component Analysis (PCA). FECG has been extracted by ICA from 25 of 30 pregnant women. The fetal P wave and T wave could be identified in 21 of the 25 cases. FECG was extracted by PCA in only one case. ICA is superior to PCA, whose separation quality highly depends on the careful positioning of the electrodes. We believe that after ICA, FECG obtained by the wavelet theory based method will become a powerful tool for the differential diagnosis of fetal arrhythmias.

Leber's hereditary optic neuropathy with intracranial arteriovenous malformation: a case report.

We reported a patient with Leber's hereditary optic neuropathy (LHON) with an intracranial arteriovenous malformation (AVM). Genetic analysis of this patient revealed a point mutation in mitochondrial DNA (mtDNA) at nucleotide position 11,778 in the ND4 subunit of complex I. Although the relationship between intracranial AVM and mtDNA mutations remains uncertain, some patients with intracranial AVM may be associated with mitochondrial abnormality. Further study is necessary to confirm whether the above conditions are coincidental or closely interrelated.

Monitoring of radioactive substances in foods distributed in Kyoto, Japan (1991-2011). - Comparison of detection rates and concentrations before and after the Fukushima Daiichi Nuclear Power Plant accident - .

Since the Chernobyl Nuclear Power Plant accident, radioactive substances have been continually monitored in foods collected in the city of Kyoto, Japan. The importance of the monitoring was increased by the Fukushima Daiichi Nuclear Power Plant accident in March 2011. Here, the detection rates and concentrations of radioactive substances were compared among food samples collected before and after the accident in Fukushima prefecture. Before the accident, (137)Cs was the only radioactive substance detected in foods. The detection rate was 70% for fish and shellfish samples and the highest concentration was 1.7 Bq/kg. It was also 83% for fresh mushroom samples and the highest concentration was 7.5 Bq/kg. In contrast, the detection rate was low for vegetables and the concentrations were also lower than those of the above samples. On the other hand, after the accident, (131)I was detected in food produced in the Tohoku and Kanto areas. Actually, (131)I (3,400 Bq/kg), (134)Cs (280 Bq/kg), and (137)Cs (280 Bq/kg) were detected in mizuna, a leaf vegetable, on March 23, 2011. These radioactive substances were detected in all leaf vegetable samples examined in March and April 2011, but they were not detected in samples examined in November 2011. (131)I was not detected in any food sample examined after May 2011. However, (137)Cs (average=7.9 Bq/kg) was consistently detected in fish and shellfish samples until November, although the concentrations were less than the regulatory limits. It appears unlikely that foods containing radioactive substances over the regulatory limits are currently being distributed in Kyoto.

Detection of extra components of T wave by independent component analysis in congenital long-QT syndrome.

BACKGROUND: The main ECG criteria for the diagnosis of long-QT syndrome (LQTS) include abnormal T-wave morphology as well as prolonged QT interval. The T wave in LQTS probably includes additional components of the myocardial repolarization process, which are derived from aberrant ion currents. We investigated whether independent component analysis (ICA) can extract such abnormal repolarization components. METHODS AND RESULTS: Digital ECG data were obtained as a time series from 10 channels using 20 surface electrodes in 22 patients with genetically confirmed LQTS type 1 (LQT1) and 30 normal subjects. In each case, T-wave area was analyzed by radical ICA after noise reduction by the wavelet thresholding method. Furthermore, inverse ICA was applied to determine the origin of each independent component (IC). Radical ICA revealed that a T-wave consisted of 4 basic ICs in all control subjects, whereas ≥ 5 (mostly 6) ICs were identified in all 22 patients with LQT1. The extra ICs, which were not evident in normal subjects, were assumed to contribute to the formation of abnormal T-wave morphology. The extra ICs were identified even in patients with normal QTc values and in those taking ß-blockers. Inverse ICA indicated that the additional ICs originate predominantly from the late phase of the T wave of the left ventricle. CONCLUSIONS: Extra ICs appear during repolarization in all patients with LQT1 but not in normal subjects. ICA is a potentially useful multivariate statistical method to differentiate patients with LQT1 from normal subjects.

Inverse independent component analysis facilitates clarification of the accessory conductive pathway of Wolf-Parkinson-White syndrome electrocardiogram.

Our aim was to demonstrate a digital analyzing method that could extract the potential of early excitation derived from accessory conductive pathway (ACP) from fusion of the QRS complex wave of the electrocardiogram of Wolf-Parkinson-White (WPW) syndrome. A 13-year-old boy with WPW syndrome received successful catheter ablation therapy. ECG was recorded and analyzed using independent component analysis (ICA) and inverse independent component analysis (I-ICA), at pretherapy and posttherapy. We identified the ACP potential and the following potential spread to the ventricle. Results agreed with those of intracardiac mapping, locating the ACP in the left posterior side of the heart. ICA and I-ICA might be useful for noninvasive analysis of WPW syndrome ECG and other electrocardiac abnormalities.

Prenatal diagnosis of long QT syndrome by non-invasive fetal electrocardiography.

Long QT syndrome is a high-risk condition associated with arrhythmia due to its sudden cause of death. Prenatal diagnosis of long QT syndrome, however, is impossible using the fetal echocardiogram. Here we present the first reported case of long QT syndrome in which a prenatal diagnosis was made using non-invasive fetal electrocardiogram. We consider that the non-invasive fetal electrocardiogram may be a good method for diagnosing fetal QT prolongation.