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The majority of chemical experiments conducted during educational programs are carried out in laboratories because they require instructors with special skills, in addition to large, expensive instruments. Recently, there has been an increasing demand for chemical experiments that can be carried out anywhere. Herein, we propose a novel type of paper-based analytical device (PAD) for enabling quantitative analysis without the requirement for a micropipette, since the PAD features a large sample loading zone and a waste zone, enabling accurate volume control of a liquid sample. We initially employed a micropipette to evaluate the PAD and demonstrate the quantitative analysis of ascorbic acid (AA) and pH using different loading volumes. Finally, we determined the AA concentrations and pH values of commercially available beverages using disposable plastic droppers, and the obtained results were in good agreement with those obtained through conventional methods. This PAD format can therefore be used as a novel educational tool for conducting certain chemical analyses in remote learning environments.

Analytical methods with fluorescence detection are in widespread use for detecting low abundance analytes. Here, we report a simple method for fluorescence signal amplification utilizing a structure of an azide-unit pendant water-soluble photopolymer (AWP) in a microchannel. The AWP is a poly(vinyl alcohol)-based photocross-linkable polymer, which is often used in biosensors. We determined that the wall-like structure of the AWP (AWP-wall) constructed in a microchannel functioned as an amplifier of a fluorescence signal. When a solution of fluorescent molecules was introduced into the microchannel having the AWP-wall, the fluorescent molecules accumulated inside the AWP-wall by diffusion. Consequently, the fluorescence intensity inside the AWP-wall increased locally. Among the fluorescent molecules considered in this paper, 9H-(1,3-dichloro-9,9-dimethylacridin-2-one-7-yl) (DDAO) showed the highest efficiency of fluorescence signal amplification. We prepared a calibration curve for DDAO using the fluorescence intensity inside the AWP-wall, and the sensitivity was 5-fold that for the microchannel without the AWP-wall. This method realizes the improved sensitivity of fluorescence detection easily because the fluorescence signal was amplified only by injecting the solution into the microchannel having the AWP-wall. Furthermore, since this method is not limited to only the use of microchannel, we expect it to be applicable in various fields.

Preparation of high-quality protein crystals is a major challenge in protein crystallography. Natural convection is considered to be an uncontrollable factor of the crystallization process at the ground level as it disturbs the concentration gradient around the growing crystal, resulting in lower-quality crystals. A microfluidic environment expects an imitated microgravity environment because of the small Gr number. However, the mechanism of protein crystal growth in the microfluidic device was not elucidated due to limitations in measuring the crystal growth process within the device. Here, we demonstrate the real-time measurement of protein crystal growth rates within the microfluidic devices by laser confocal microscopy with differential interference contrast microscopy (LCM-DIM) at the nanometer scale. We confirmed the normal growth rates in the 20 and 30 μm-deep microfluidic device to be 42.2 and 536 nm/min, respectively. In addition, the growth rate of crystals in the 20 μm-deep microfluidic device was almost the same as that reported in microgravity conditions. This phenomenon may enable the development of more accessible alternatives to the microgravity environment of the International Space Station.

Background Recurrent vasospastic angina sometimes occurs. Fresh thrombi have been known to arise without plaque rupture at coronary spasm sites due to blood flow stagnation and intimal erosion caused by vasospasms. The relationship between recurrence of vasospastic angina and thrombus formation remains unclear. Case summary A 67-year-old man presented with sudden chest pain at rest. Electrocardiography and coronary angiography indicated vasospastic angina. His chest pain persisted despite the administration of benidipine, isosorbide mononitrate, nicorandil, and nifedipine. Coronary angiography performed one month after initial presentation showed stenosis refractory to isosorbide administration. Optical coherence tomography revealed a healed plaque, and a stent was deployed. The patient remained symptom-free at 1-year follow-up. Discussion Prolonged coronary vasospasm with limited coronary blood flow could induce total occlusion of the coronary artery, and acute thrombus formation, which resulted in healed plaque erosion. When vasospastic angina cannot be controlled, rapidly progressive stenosis caused by healed plaque erosion could be its underlying cause and mechanism. This report indicates that antiplatelet therapy may be a preventive option for future recurrent vasospastic angina, especially in those caused by healed plaques.

Ventricular arrhythmia (VA) arising from the tricuspid annulus in the posterior septum (PS) (TAPS-VA) has similar electrocardiographic characteristics as VA arising from the mitral annulus in the PS (MAPS-VA) because the two locations are adjacent. We examined the electrocardiographic characteristics that differentiate MAPS-VA from TAPS-VA and the efficacy of catheter ablation. We studied 13 patients whose VAs were successfully ablated in the TAPS (n = 7) and MAPS (n = 6). QRS morphologies of both groups were characterized by left and right bundle block morphologies in lead V1, superior axis deviation, and precordial transition at ≤ lead V3 in nine patients. Compared with TAPS-VA, MAPS-VA had (1) R

Single-molecule detection of the biomolecules in a label-free manner has a tremendous impact for various fields. Recently, we developed a label-free detection method without any pretreatment procedures, which is based on optical diffraction derived from a nanofluidic channel array (in other words, a nanowall array). However, the single-molecule detection is hampered by the inherent sensitivity of the method. We propose a solution to improve the sensitivity of the method by adjusting the height of the nanowall array. Numerical simulations showed that a larger nanowall array height could provide better sensitivity, but a lower nanowall array height could provide better sensitivity difference, contrary to what we would intuitively expect. We used a 250 nm height nanowall array to achieve a label-free detection of 0.18 DNA molecules to verify the simulation prediction. These results demonstrate our method has a potential to be implemented in a highly sensitive refractometer with small sample consumption.

The detection system which enables simultaneous fluorescence polarization (FP) measurement of multiple samples was proposed and proven by a proof-of-concept experiment on the viscosity dependence of FP of fluorescein sample in water-ethylene glycol solution and another experiment on the FP immunoassay of prostaglandin E2 sample. The measurement principle of FP is based on the synchronization between the orientation of the liquid crystal molecules and the sampling frequency of a CCD. This report is the first description of the simultaneous FP measurement of multiple samples. This system has a great potential for equipment miniaturization and price reduction as well as providing simultaneous FP measurement of multiple samples.

We describe the case of a 23-year-old woman who had His-Purkinje system-related incessant ventricular tachycardia with a narrow QRS configuration. The ventricular tachycardia was ablated successfully in the left coronary cusp where the earliest endocardial activation had been recorded. We hypothesize that a remnant of the subaortic conducting tissue was the source of the ventricular arrhythmias.

Background The long-term survival of vasospastic angina (VSA) patients is generally good, so long as they remain on calcium channel blockers (CCBs) and avoid smoking. However, the pathogenesis, appropriate treatments, and prognosis of VSA associated with cardiac arrest remain unclear. This study aimed to elucidate the clinical features and long-term outcomes of patients with VSA associated with cardiac arrest. Methods and results Eighteen consecutive patients with VSA associated with cardiac arrest [13 patients resuscitated after out-of-hospital cardiac arrest (OHCA) and 5 resuscitated after in-hospital-cardiac arrest] were retrospectively analyzed. Sixteen of the eighteen patients were smokers. None had other cardiac diseases possibly causing cardiac arrest. Although 1 patient resuscitated after OHCA later died of cerebral hypoxia, the remaining 17 were discharged without complications. One patient died of cancer 50 months after resuscitation. The other 16 patients are still alive and none have shown ventricular arrhythmias, syncope, or cardiac arrest during a mean follow-up of 67 months. All are treated with long-acting CCBs/nitrates and successfully quit smoking. Six patients received implantable cardioverter defibrillators (ICD). However, none demonstrated any ventricular arrhythmias and appropriate ICD actuation was achieved. Conclusion Appropriate medical treatment can achieve favorable long-term outcomes even for patients with VSA associated with cardiac arrest.

A 58-year-old man was referred to our emergency room with hemodynamically unstable sustained ventricular tachycardia (VT). The morphology of the VT exhibited a left bundle branch block and inferior axis deviation. He had no past history of cardiovascular disease. Echocardiography, cardiac catheterization, cardiac biopsy, gallium scintigram, myocardial scintigram, T1,T2-weighted magnetic resonance imaging (MRI), and gadolinium-enhanced cine MRI did not detect any structural heart disease or abnormal cardiac function. However, delayed-enhancement MRI (DE-MRI) detected a focal intramural scar within the septal ventricular outflow tract. An electrophysiological study revealed a sustained VT with several morphologies and the entrainment phenomenon. Radiofrequency catheter ablation to the site corresponding to the focal scar detected by DE-MRI successfully eliminated the VT.

Limited information is available about focal atrial tachycardia (AT) arising from cavotricuspid isthmus (CTI). The purpose of this study is to evaluate the electrocardiographic and electrophysiologic characteristics of a focal AT arising from the CTI. From a consecutive series of 92 patients undergoing radiofrequency catheter ablation (RFCA) for focal AT, three (4.4%) patients (three men) with a focal AT arising from the CTI were studied. The median age was 71 years (range, 50 to 81 years). None of the patients had a history of CTI-dependent atrial flutter. The electrocardiogram (ECG) of a focal AT showed a significant negative F-wave in the inferior leads. Focal AT could be reproducibly initiated and terminated with programmed stimulation. The focus of the tachycardia was localized to the central isthmus in two and the paraseptal isthmus in one patient. The median tachycardia cycle length was 275 ms (range, 260 to 310 ms). In two patients, the focal AT was adenosine insensitive. In all of the patients, tachycardia was entrained from multiple right atrial sites, including the earliest activation site. RFCA was acutely successful in all patients. Long-term success was achieved in all patients over the median follow-up of 18 months (range, 6 to 33 months). Cavotricuspid isthmus is an uncommon site of origin for focal AT. This focal AT has unique electrocardiographic characteristics such as saw-tooth morphology on ECG and is suggested to be caused by a focal reentrant circuit located at the CTI. Long-term success is achieved with focal ablation.

Category: 27. Clinical Electrophysiology—Ventricular ArrhythmiasSession-Poster Board Number: 1057-381 Authors: Yoshihiro Yamashina, Tetsuo Yagi, Akio Namekawa, Akihiko Ishida, Hirokazu Sato, Takashi Nakagawa, Manjirou Sakuramoto, Eiji Sato, Tomoyuki Yambe, Sendai City Hospital, Sendai, Japan, Tohoku University School of Medicine, Sendai, Japan Background: The relationship between J waves during sinus rhythm and idiopathic ventricular tachycardia (VT) or premature ventricular complexes (PVCs) originating from the right ventricular outflow tract (RVOT) has not been reported. The aim of this study was to investigate the prevalence and characteristics of idiopathic RVOT-VT/PVCs associated with J waves. Methods: The study enrolled 121 consecutive idiopathic RVOT-VT/PVC patients (mean age 45 ± 16 years, 46 males) undergoing radiofrequency catheter ablation (RFCA). The prevalence of J waves was assessed. The clinical and electrophysiological data were compared between the patients with J waves (J-wave group) and those without (Non-J-wave group). Results: J waves were present in 53 (43.8%) idiopathic RVOT-VT/PVC patients. The distribution of the J waves was as follows: Inferior leads = 62%, inferior-lateral leads = 24.5% and lateral leads = 13.2%. The J-wave group had a higher incidence of sustained VT (22.6% vs. 3.5%, P

Fluorescence polarization (FP) offers easy operation and rapid processing, making it implementable in molecular interaction analysis. Previously we have developed a unique FP measurement system using a liquid crystal (LC) layer and an image sensor. The system is based on a principle of synchronized detection between the switching rate of the LC layer and the sampling rate of the CCD. The FP system realized simultaneous multiple sample detection; however, the measurement precision was lower than that of the conventional FP apparatus. The main drawbacks were low light transmittance of the LC layer and insufficient synchronization between the LC layer and CCD. In this paper, we developed a new FP analyzer based on LC-CCD synchronization detection. By using a newly designed LC with high transmittance and improving synchronization, the performance of the system has been dramatically improved. Additionally, we reduced the cost by using an inexpensive CCD and an LED as the excitation source. Simultaneous FP immunoassay of multiple samples of prostaglandin E2 was performed. The error rate of the FP system is reduced from 16.9% to 3.9%, as comparable to the commercial conventional FP system. Published by AIP Publishing.

Background Cardiac memory (CM) after idiopathic left ventricular tachycardia (ILVT) mimics ischemic T wave inversion (TWI) induced by acute coronary syndrome (ACS). We aimed to establish electrocardiography criteria for differentiating the CM from ischemic TWI. Methods and results We evaluated 16 ILVT and 48 ACS patients. We identified TWI after ILVT in 9/16 patients (CM group), typically in leads II, III, aVF, aVR, and V 4–6 . The characteristics of CM were similar to TWI induced by ACS involving right coronary artery, but the CM group had more TWI in V 4 and shorter QTc. The criteria of (1) positive T in aVL, (2) negative or isoelectric T in II, and (3) negative T in V 4–6 or (4) QTc Conclusion CM after ILVT can be differentiated in most cases from ischemic TWI by the distribution of TWI and the QTc.

The comparative usefulness of 10 min of beat-to-beat 12-lead QT dispersion (QTd) and QT interval variability index (QTVI) analysis for identifying patients with organic heart disease (OHD) at risk for ventricular arrhythmias was assessed in 86 subjects: 54 had OHD without a history of ventricular arrhythmias, 15 had OHD with documented ventricular tachycardia, and there were 17 controls. The following parameters were analyzed among the groups: (1) the average QTd (mean QTd), (2) the difference between the maximum and minimum QTd observed over the recording time (QTd variation), (3) the maximum difference of QTd between consecutive beats (QTd maximum), (4) the QTd standard deviation (QTd variability), and (5) QTVI, calculated in lead I or II according to an established formula: log 10 [(QTv/QTm2) / (HRv/HRm2)]. All the analyzed parameters were significantly increased in the patients with and without ventricular tachycardia when compared with the controls. QTd variation, QTd maximum and QTd variability were the only variables that remained significantly increased in the group of patients with documented ventricular tachycardia, compared with those without arrhythmia. Thus, beat-to-beat fluctuations of both the QT interval and QTd may be markers of temporal electrical instability in patients with OHD. (Circ J 2003; 67: 125 - 128)

Nonischemic dilated cardiomyopathy (DCM) is associated with a high risk of sudden cardiac death. Signal-averaged electrocardiography (SAECG) is a useful clinical tool for detecting late ventricular potentials (LP). Gap junction alterations have recently been shown to be involved in the pathogenesis of ventricular arrhythmias in DCM; however, the possible relationship between gap junctional connexin43 (C x 43) expression and SAECG has not yet been evaluated. In the present study 16 patients (47+/-13 years) with DCM who had undergone SAECG testing were evaluated. In each patient, the expression of C x 43 proteins was qualitatively and quantitatively determined using immunoconfocal microscopy and right ventricular biopsy specimens. The level of expression of C x 43 protein was defined as the proportion of tissue area occupied by C x 43 (percent tissue area) in each test area. The abundance and distribution of the C x 43 signal was assessed in relation to LP. Late ventricular potentials were positive in 5 patients (LP (+) group) and negative in 11 patients (LP (-) group). The incidence of sustained ventricular tachycardia in the LP (+) group was higher than that in the LP (-) group (80% vs 18%, p=0.04). The percent tissue area of C x 43 in the LP (+) group was significantly lower than that in the LP (-) group (p=0.02). Furthermore, C x 43 protein in the LP (+) group was distributed more heterogeneously than that in the LP (-) group (p=0.001). The heterogeneous expression of C x 43 protein may contribute to impaired ventricular conduction, which may be related to the LP detected on SAECG.

ObjectivesThis study was designed to determine the prognostic value of onset heart rate (OHR) in T-wave alternans (TWA) in patients with nonischemic dilated cardiomyopathy (DCM).BackgroundOne of the current major issues in DCM is to prevent sudden cardiac death (SCD). However, the value of the OHR of TWA as a prognostic indicator in DCM remains to be elucidated.MethodsWe prospectively investigated 104 patients with DCM undergoing TWA testing. The end point of this study was defined as SCD, documented sustained ventricular tachycardia/ventricular fibrillation. Relations between clinical parameters and subsequent outcome were evaluated.ResultsForty-six patients presenting with TWA were assigned to one of the following two subgroups according to OHR for TWA of ≤100 beats/min: group A (n = 24) with OHR ≤100 beats/min and group B (n = 22) with 100 < OHR ≤ 110 beats/min. T-wave alternans was negative in 37 patients (group C) and indeterminate in 21 patients. The follow-up result comprised 83 patients with determined TWA. During a follow-up duration of 21 ± 14 months, there was a total of 12 arrhythmic events, nine of which included three SCDs in group A, two in group B and one in group C. The forward stepwise multivariate Cox hazard analysis revealed that TWA with an OHR ≤100 beats/min and left ventricular ejection fraction were independent predictors of these arrhythmic events (p = 0.0001 and p = 0.0152, respectively).ConclusionsThe OHR of TWA is of additional prognostic value in DCM.

Approaches to ex vivo gene therapy hold great promise for the treatment of central nervous system disorders where there is currently no care or enough treatment for suffering patients. In this review we have focused on the application of ex vivo gene therapy techniques in Parkinson's disease models, however, the issues and approaches are applicable to other neurodegenerative disorders. In utilizing the ex vivo strategy two considerations are critical for delivery of therapeutic levels of transgene product to the target organ: (i) the vector system and (ii) the cell type for grafting. We describe different vector systems that are currently available and review the various cell types that have been genetically modified and grafting into the striatum of animal models with experimental Parkinson's disease. The strategies for application of gene therapy techniques to the treatment for Parkinson's disease have expanded beyond the classical dopamine replacement toward the use of neurotrophic factors in enhancing cell function or preventing cell death. In addition, we explore the utility of autologus primary skin fibroblasts as alternative cell type for ex vivo gene therapy in the animal model of Parkinson's disease. These results have general implications for the application of ex vivo gene therapy to human neurological diseases and specific implications for Parkinson's disease.

[目的] Permanent form of junctional reciprocating tachycardia (PJRT) のカテーテルアブレーション (ABL) で得られた所見から, その副伝導路の特徴や至適通電部位を明らかにする, [方法] 対象は心電図上long RP'頻拍を呈し, 電気生理学的検査で長い伝導時間と減衰伝導を示す不顕性の副伝導路 (SK) が関与する房室リエントリー性頻拍と診断された8例 (男4例, 女4例, 21～72歳, 平均43±17歳) , 10SKである, 10SKに対しABL時の通電は計34回 (1～7, 平均3.4回/1SK) 行い, 一過性または永続的な頻拍の停止がみられた15通電 (44%) (停止群) と停止しなかった19通電 (非停止群) の電気生理学的指標を比較検討した.ABLは1SK (2通電) を除き弁上アプローチを用いた. [結果] 1) SKの局在: 右後中隔が4例 (40%) , 右後壁2例 (20%) , 右中中隔1例 (10%) , 左後壁1例, 左側壁1例, 左前壁1例であった.2例は2本のSKを合併し (右後中隔と右後壁, 右中中隔と右後壁) , 3例は左側に副伝導路を有するWPW症候群のABL後にPJRTが出現した (SKは右後中隔, 左後壁, 左側壁) .2) SKのABL: 停止群は非停止群に比し, 通電部位の心房電位が逆行性P波からの先行度が強く (37±12vs, 26±16msec, p

We studied the effect of intraatrial reentry (IAR) on initiation of orthodromic reentrant tachycardia (ORT) in 150 patients with Wolff-Parkinson-White syndrome using His-bundle recording and the atrial extrastimulus technique. IAR was initiated by premature atrial stimulation in 44 patients (29%), and it was followed by ORT in 16 patients (11%). In 8 patients (5%), IAR promoted the initiation of ORT, whereas in 5 patients (3%), IAR inhibited the initiation of ORT. These findings suggest that ORT is frequently induced following IAR. IAR, which was frequently observed during electrophysiological studies, seems to play an important role in the initiation of ORT.

72歳男性, 陳旧性下壁梗塞に心室頻拍 (VT) を合併した.VTは左軸偏位を伴う右脚ブロック波形で, VT中の通電部位からの電位はQRSより50msec先行してプレポテンシャルがみられた.115/分のVTに対し同部から高頻度心室刺激を行ない頻度を5/分ずつ増すと, S-QRS間隔は徐々に延長し, QRS波形は135/分まではVTと同じであったが, 140/分でS-QRS間隔の35msecの延長とともに変化し, 155/分まで異なるQRS波型が不変のままでS-QRS間隔は徐々に延長した.この現象は, 緩徐伝導部位 (SCA) の途中に伝導時間が長く不応期が短いSCAが接続され, 高頻度では遠位部のブロックが出現し, 他方のSCAを伝播し興奮の出口が変化することを想定させた.同部でVT中に通電を行なうと, 2拍のVT後に洞調律となり, 30秒の通電中VTと同型の頻脈性心室調律が7拍出現した.2週後の心臓電気生理検査, 16カ月の追跡期間でVTはみられていない.アブレーション部位に関する検討を加え報告する.

症例は15歳の男子高校生.心拍数105/分で頻拍依存性の不完全右脚ブロック波形のlong RP頻拍が出没を繰り返していた.電気生理学的検査中, 頻拍は房室ブロックが出現しても持続したが, ヒス束が不応期の時の心室刺激で奇異性遅延を示した.心室刺激時に2種類の副伝導路の存在が示唆され, 一方は潜在性のatrio-hisian pathwayで, もう一方は, 潜在性で逆行性に減衰伝導を示し, 房室接合部の遅伝導路と右脚を連結するatrio-fascicular pathway (AFP) が考えられた.頻拍の回路は, 房室接合部の速伝導路→右脚→AFP→房室接合部の遅伝導路→心房で構成され, A-Hブロックが出現したときのみ非通常型房室結節リエントリーへ回路が変化したと思われた.PJRTの機序として心房端が房室接合部の遅伝導路, 心室端が右脚に存在する潜在性AFPが関与することが推測された1例を経験したので報告した.

心房粗動 (AF) の誘発に及ぼす抗不整脈薬の影響について検討した.対象はジソピラミド (DP) 2mg/kg投与前後で, 右房高位刺激により通常型AFの誘発予防効果が検討できた15例.投与後誘発不能となったのは5例で誘発帯縮小は2例であり, これら7例をE群, 投与後のみ誘発された2例と誘発帯拡大例6例をN群とした.E群はN群に比し, 右房有効不応期 (ERP) の延長比は有意に大で (p

Pathological studies have demonstrated that the cavotricuspid isthmus (CTI) is often composed of discrete muscle bundles, which are thought to be represented electrically as high-amplitude electrograms. Based on this observation, we visualized the bundles using an electro-anatomical mapping system (EAMS) and investigate the efficacy of bundle ablation which is an ablation method for selectively targeting high-voltage sites obtained by high-density electro-anatomical mapping along the CTI.Sixty patients with atrial flutter were randomly assigned to cavotricuspid isthmus ablation using a conventional anatomical approach (Group 1) or bundle ablation approach (Group 2). In Group 2, CTI was mapped in detail with EAMS, and we visualized the bundles that were 1.5 mV or more on a bipolar voltage map. Radiofrequency (RF) ablation was delivered sequentially from the maximum voltage site at the shortest distance of the bundle until bidirectional block was achieved.Bidirectional block was achieved in all patients. Mean ablation times (Group 1, 1,392 + or - 960 s; Group 2, 638 + or - 342 s, p0.01), the mean number of RF applications (Group 1, 31.7 + or - 23.6; Group 2, 13.0 + or - 7.0, p0.01), and fluoroscopy times (Group 1, 50.4 + or - 28.3 min; Group 2, 42.3 + or - 21.3 min, p0.01) were significantly shorter in Group 2 than those in Group 1.Bundle ablation at CTI is highly effective for achieving a bidirectional block requiring shorter ablation times, shorter fluoroscopy times, and fewer RF applications.

Characteristics of Pulmonary Artery Arrhythmias.Introduction: The precise incidence and characteristics of ventricular arrhythmias originating from the pulmonary artery have not been fully described. The purpose of this prospective study was to clarify these points. Methods: Thirty-three consecutive patients with an idiopathic left bundle branch block and inferior-axis deviation type ventricular arrhythmia were included. All patients underwent detailed electroanatomical mapping (CARTO, Biosense-Webster, Diamond Bar, CA, USA) during sinus rhythm prior to the catheter ablation. The precise location of the catheter tip at the successful ablation site was confirmed by both electroanatomical mapping and contrast radiography. The clinical and electrophysiological data were compared between the right ventricular outflow tract (RVOT) arrhythmia patients (RVOT group) and PA arrhythmia patients (PA group). Results: Eight patients (8/33 patients: 24.2%) had their ventricular arrhythmias successfully ablated within the PA. The local bipolar electrogram at the successful ablation sites in the PA group exhibited a significantly greater duration (P < 0.05) and lower amplitude (P < 0.05) than did those in the RVOT group (n = 19). In the PA group, all patients exhibited a multicomponent electrograms composed of a spiky potential and a dull potential, which might have consisted of near-field PA activation and a far-field ventricular activation, respectively, at the successful ablation site. Direct ablation to the spiky electrogram was able to eliminate the arrhythmias in all the PA group patients. Conclusions: PA arrhythmias may be more common than previously recognized. Careful mapping and interpretation of low amplitude and multicomponent electrograms are important for recognizing ventricular arrhythmias originating from the PA. (J Cardiovasc Electrophysiol, Vol. 21, pp. 163-169, February 2010)

There are few studies evaluating the distribution of successful ablation sites of idiopathic right ventricular outflow tract (RVOT) arrhythmias using a three-dimensional electroanatomical mapping system. This study aims to clarify the favorite site of idiopathic RVOT arrhythmias through electroanatomical voltage mapping using the CARTO system (Biosense Webster, Diamond Bar, CA, USA).A consecutive series of 72 patients (mean age 43.6 +/- 16.2 years, 32 males) who underwent radiofrequency catheter ablation (RFCA) for a total of 82 morphologies of idiopathic RVOT arrhythmias were studied. Detailed three-dimensional electroanatomical voltage maps of the RVOT were obtained using the CARTO system prior to the RFCA during sinus rhythm. The voltage on bipolar electrogram was defined as follows: amplitude0.5 mV as "low-voltage zone," amplitude between 0.5 and 1.5 mV as "transitional-voltage zone," and amplitude1.5 mV as "high-voltage zone." Successful ablation sites were electroanatomically classified into each voltage zone.Successful ablation was acquired in 63 patients and 71 RVOT arrhythmias (63/72 patients: 87.5%, 71/82 RVOT arrhythmias: 86.5%). In the successful group, three arrhythmias (4.2%) were classified in the low-voltage zone, 63 arrhythmias (88.7%) in the transitional-voltage zone, and five arrhythmias (7.0%) in the high-voltage zone.This study indicates that the vast majority of successful ablation sites for idiopathic RVOT arrhythmias are located in the transitional-voltage zone. Mapping of the transitional-voltage zone may be an important landmark of RFCA for RVOT arrhythmia.

A 62-year-old-male with old inferior myocardial infarction suffered from drug resistant electrical storms and frequent shocks from an implantable cardioverter defibrillator. Emergent radiofrequency catheter ablation was performed. The patient underwent substrate mapping that uses an electro-anatomical mapping system during sinus rhythm because of multiple QRS morphologies and hemodynamic instability during ventricle tachycardia. The electro-anatomical map revealed a massive low voltage zone (

Summary Although intracerebral transplantation might become a new strategy for the treatment of neurological diseases, there are many problems for the grafts, We examined the possibilities of primary skin fibroblasts as a new graft for Parkinson's disease. Rat primary skin fibroblasts were transfected with a retrovirus vector containing eDNA of human tyrosine hydroxylast typel (TH) (pLTHSNL) or cytomegalovirus promoter (pCTHSNL) as a foreign promoter. In these genetically modified fibroblasts, catecholamine production and release were analyzed in vitro by immunocytochemistry and high performance liquid chromatography with electrochemical detection (HPLC-ECD), Being supplemented with biopterin (BH4; (6R)-L-erythro-tetrahydrobiopterin) cofactors required for TH activity, these cells produced and released L-DOPA into the culture medium. When combined with a foreign promoter and BH4, L-DOPA production increased in a timedependent manner, which was not affected by the number of cell-passages and the duration of liquid nitrogen freezing . These facts suggest that the amount of L-DOPA secreted from transplanted genetically modified fibroblasts can be manipulated by an inserted promoter the exogenously administered BH4. Thus genetically modified primary skin fibroblasts transfected with THcDNA using retrovirus vector system may hold promise as a graft for transplantation and gene therapy for Parkinson's disease.

The crista terminalis (CT) is reportedly a critical barrier for maintaining typical atrial flutter (AFL), but recent observations have suggested the presence of posteromedial functional block, as well as crista conduction. Therefore, this study was designed to identify the correlation between the posterior boundary of AFL and anatomical architecture in the human right atrium (RA) using 3-dimensional (D) intracardiac echocardiography (ICE). In 11 patients with AFL (typical 9, reverse typical 2), mapping with a 10-pole (n=5) or 32-pole (n=6) catheter was performed during AFL. ICE was used to determine the catheter's position relative to the intra-atrial structures. In all patients, double potentials were recorded at the posteromedial RA and the catheter positions were recognized as posterior to the CT by 3-D ICE. Double potentials were not recorded on the CT, and the activation sequence revealed a craniocaudal direction in the 9 patients with typical AFL and caudocranial direction in the 2 patients with reverse typical AFL. These findings demonstrate that the posterior boundary of the AFL circuit is in the sinus venosa region posterior to the CT, which may provide an important insight into the mechanism of maintaining AFL.

Connexin43 Expression in DCM.Introduction: Gap junction alterations recently have been implicated in chronic heart failure, but direct evidence between gap junction manifestation in nonischemic dilated cardiomyopathy (DCM) is lacking. The current study examines whether qualitative changes or altered distribution of gap junctional connexin43 (Cx43) are related to global ventricular function and ventricular arrhythmia in DCM. Methods and Results: We investigated 31 DCM patients (52 ± 15 years) and 5 control subjects (55 ± 10 years). Expression of Cx43 proteins was qualitatively and quantitatively determined using immunoconfocal microscopy in right ventricular biopsy specimens from each patient. The expression level of Cx43 protein was defined as the proportion of tissue area occupied by Cx43 (percent tissue area) in each test area. Cx43 immunoreactive signal expressed as percent tissue area was not correlated with the change in left ventricular ejection fraction (P = 0.17). Of 31 DCM patients, 23% subsequently developed sustained ventricular tachycardia (VT), which allowed retrospective division of the samples into two groups: non-VT and VT. Left ventricular ejection fraction was comparable in both groups, but the percent tissue area in the VT groups was significantly decreased compared with that of the non-VT groups (P = 0.03). Furthermore, Cx43 protein was distributed heterogeneously in the VT groups (P < 0.0001). Conclusion: Heterogeneous reduction of Cx43 protein may result in development of malignant ventricular arrhythmia in DCM.

To clarify the differences between the incessant and paroxysmal types of the permanent form of junctional reciprocating tachycardia, we performed electrophysiologic studies in 11 patients with long RP' tachycardia using a slowly conducting accessory pathway as the retrograde conduction, and concluded that the short AH intervals during sinus rhythm and tachycardia are very important factors in the development of incessant tachycardia.

Purpose: Corpus callosotomy (CC) has recently been recognized as an effective treatment for patients with intractable generalized seizures. Experimental studies also reported the same seizure-suppressive effects. We investigated the effects of sectioning the corpus callosum in models of epilepsy in cats. Methods: Acute and subacute models of epilepsy were made by the topical application of estrogen and cobalt powder, respectively, at the left anterior sigmoid gyrus (ASG). The electrocorticogram (ECoG) and steady potentials (SPs) were recorded from both sides of the anterior sigmoid gyrus and the ventrolateral (VL) nucleus of the thalamus. The spindle-like afterdischarges were elicited by direct stimulation of the cortex or VL nucleus of thalamus. The “surface negative (SN) wave” produced by pyramidal tract stimulation and recorded at the cortical surface has been identified as a reflection of postsynaptic potentials generated through recurrent inhibitory pathways (Humphrey et al. 1968). SN waves were analyzed for the assessment of the cortical inhibitory mechanisms before and after sectioning the corpus callosum. Results: Topical application of estrogen to the left ASG (acute model) induced spike-waves on both sides of the ASG and VL. The SP showed a negative shift on the same side as the estrogen application: however, no change in the SP was seen on the contralateral side. In this (acute) model, a remarkable reduction or disappearance of spike-waves on the side contralateral to estrogen application, was seen just after the sectioning of the corpus callosum. The spindle-like afterdischarges were also difficult to induce on the same side as estrogen application after callosal sectioning. Cobalt powder also induced spike-waves after topical application to the left ASG (subacute model). The spindle-like afterdischarges showed a reduction after the callosal sectioning. The SN waves gradually diminished in amplitude after topical application of cobalt powder on the same side of the ASG as the application. In the contralateral ASG, the SN waves showed a slight reduction in amplitude. These phenomena were presumably due to depression of recurrent postsynaptic inhibition caused by the topical application of the epileptogenic agents. After callosal section, the SN waves recovered in amplitude on both sides. Conclusions: These data suggest that the corpus callosum is maintaining epileptiform activity during the advanced stages of epilepsy. They also suggest that sectioning of the corpus callosum suppress epileptic activity because of recovery of cortical inhibitory mechanisms as represented by the amplitude of the SN wave.