Characteristics of systolic and diastolic potentials recorded in the left interventricular septum in verapamil-sensitive left ventricular tachycardia

We studied the electrophysiological characteristics of systolic (SP) and diastolic (DP) potentials recorded during sinus rhythm (SR) in the left interventricular septum of a 27 year-old woman presenting with verapamil-sensitive idiopathic left ventricular tachycardia (VT). During SR, and during VT, SP was activated from ventricular base-to-apex, and DP from apex-to-base. SP and DP were both detected at the site of successful ablation during SR, whereas during VT, DP was detected away from the earliest activation site. Thus, SP apparently reflected a critical component of the reentrant circuit, while DP reflected the activation of a bystander pathway

Grafting of iPS cell-derived tenocytes promotes motor function recovery after Achilles tendon rupture

ヒトのiPS細胞から腱の細胞を作製する --アキレス腱断裂のラットに移植し、機能回復を確認--. 京都大学プレスリリース. 2021-08-31.Repairing tendon injuries with stem cells. 京都大学プレスリリース. 2021-08-31.Tendon self-renewal is a rare occurrence because of the poor vascularization of this tissue; therefore, reconstructive surgery using autologous tendon is often performed in severe injury cases. However, the post-surgery re-injury rate is relatively high, and the collection of autologous tendons leads to muscle weakness, resulting in prolonged rehabilitation. Here, we introduce an induced pluripotent stem cell (iPSC)-based technology to develop a therapeutic option for tendon injury. First, we derived tenocytes from human iPSCs by recapitulating the normal progression of step-wise narrowing fate decisions in vertebrate embryos. We used single-cell RNA sequencing to analyze the developmental trajectory of iPSC-derived tenocytes. We demonstrated that iPSC-tenocyte grafting contributed to motor function recovery after Achilles tendon injury in rats via engraftment and paracrine effects. The biomechanical strength of regenerated tendons was comparable to that of healthy tendons. We suggest that iPSC-tenocytes will provide a therapeutic option for tendon injury

Dispersion of single-walled carbon nanotubes modified with poly-l-tyrosine in water

In this study, complexes composed of poly-l-tyrosine (pLT) and single-walled carbon nanotubes (SWCNTs) were produced and the dispersibility of the pLT/SWCNT complexes in water by measuring the ζ potential of the complexes and the turbidity of the solution were investigated. It is found that the absolute value of the ζ potential of the pLT/SWCNT complexes is as high as that of SWCNTs modified with double-stranded DNA (dsDNA) and that the complexes remain stably dispersed in the water at least for two weeks. Thermogravimetry analysis (TGA) and visualization of the surface structures of pLT/SWCNT complexes using an atomic force microscope (AFM) were also carried out

Irregular atrial flutter following pulmonary vein isolation for persistent atrial fibrillation

AbstractA 65-year-old man with a history of refractory paroxysmal atrial fibrillation (AF) underwent catheter ablation for persistent AF lasting 2 months. AF was not terminated after complete isolation of the 4 pulmonary veins (PV). Instead, it was transformed to a sustained atrial tachyarrhythmia with beat-to-beat variability in the atrial cycle length. A 12-lead electrocardiogram during tachycardia showed negative flutter-like waves in the inferior leads. Entrainment pacing along the tricuspid annulus confirmed the diagnosis of irregular cavotricuspid isthmus (CTI)-dependent typical atrial flutter (AFL). Linear ablation of the CTI terminated AFL and restored sinus rhythm

Typical atrial flutter with atypical flutter wave morphology due to abnormal interatrial conduction

We report a case of typical counterclockwise atrial flutter (AFL) with conduction block from right to left atrium along the coronary sinus (CS) musculature, confirmed by discontinuous CS activation sequence during pacing near the ostium and differential right atrial pacing. AFL was associated with an atypical flutter wave morphology, due to the detour of the activation wavefront from right to left atrium via alternate interatrial electrical connections, such as Bachmann’s bundle, the interatrial septum, or both. (Cardiol J 2011; 18, 4: 450–453

Predictors of Pericardial Effusion in Patients Undergoing Pulmonary Artery Banding

Background:Although pulmonary artery banding (PAB) is a common palliative procedure for pediatric heart malformation, there are concerns of pressure overload and concomitant immune reactions in the right ventricle causing postsurgical complications such as pericardial effusion. At this time, no clear guidelines as to potential risk factors or procedural contraindications have been widely disseminated. Therefore, a study was undertaken to examine wide-ranging factors to find potential biomarkers for postsurgical pericardial effusion formation risk.Methods:A retrospective study was conducted on all cardiac surgeries performed over an eight-year period, and the main inclusion criterion was pericardial effusion development after PAB that required surgical drainage. Nine cases were then analyzed against a control group of 45 cases with respect to body measurements, concomitant surgeries, genetic screens, laboratory tests results, and cardiac function parameters.Results:Trisomy 21 was strongly associated with the development of severe pericardial effusion after PAB, and postoperative serum albumin levels in patients with trisomy 21 were associated with pericardial effusion development. Other parameters showed no significant correlation with pericardial effusion development.Conclusions:Our data indicate a strong association between trisomy 21 and pericardial effusion requiring drainage after PAB, which is in line with translational research findings. Pressure overload from PAB may play a role in the formation of severe pericardial effusion that is exacerbated by cardiac structural defects commonly associated with trisomy 21. Surgical teams should therefore use caution and plan to implement drainage in PAB cases, and postoperative serum albumin may serve as a useful biomarker for pericardial effusion formation

Carbon Ion Radiotherapy in a Hypo-fractionation Regimen for Stage I Non-SmallCell Lung Cancer

From 1994 to 1999, we conducted a phase I/II clinical trial for stage I non-small cell lung cancer (NSCLC) by using carbon ion beams alone, demonstrating optimal doses of 90.0GyE in 18 fractions over 6 weeks (Protocol #9303) and 72.0GyE in 9 fractions over 3 weeks ( #9701) for achieving more than 95% local control with minimal pulmonary damage. In the present study, the total dose was fixed at 72.0GyE in 9 fractions over 3 weeks (#9802), and at 52.8GyE for stage IA and 60.0GyE for stage 1B in 4 fractions in 1 week (#0001). Following this schedule, we conducted a phase II clinical trial for stage I NSCLC from 1999 to 2003. We also conducted a phase I/II single fractionation clinical trial (#0201), a dose escalation study. The total dose was initially 28.0GyE in 2003, and it was raised to 50.0GyE in 2011. The local control rate for all patients (#9802 and #0001) was 91.5%, and those for T1 and T2 tumors were 96.3% and 84.7%, respectively. The 5-year cause-specific survival rate was 67.0% (IA: 84.4, IB: 43.7), and overall survival was 45.3% (IA: 53.9, 1B: 34.2). No adverse effects greater than grade 2 occurred in the lung. In a single fractionation trial, the 5-year local control rate for 151 patients was 79.2%, and the control rates for T1 and T2 tumors were 83.6% and 72.2%, respectively. No adverse effects greater than grade 2 occurred in the lung. Carbon beam radiotherapy, an excellent new modality in terms of high QOL and ADL, was proven to be a valid alternative to surgery for stage I cancer, especially for elderly and inoperable patients.Heavy Ion in Therapy and Space Radiation Symposium 2013(HITSRS2013

Carbon ion radiotherapy for oligo-recurrence in the lung.

The clinical results after carbon ion radiotherapy for the metastatic lung tumors believed to be in the state of oligo-recurrence were evaluated. One hundred and sixteen lesions in 91 patients with lung cancer metastasis were treated with carbon ion radiotherapy at our institute from April 1997 to February 2011. Regarding the prescribed dose, total dose ranged between 40 gray equivalents (GyE) and 80 GyE, and fraction size ranged from 1 to 16 fractions. After a median followup period of 2.3 years (range, 0.3-13.1 years), the statistical overall survival rate and local control rate were 71.2% and 91.9% at 2 years after treatment, respectively. Treatment-related side effects were not a clinical problem. When classified by the primary organ, there were 49 cases of lung cancer, 20 cases of colorectal cancer, and 22 cases of others. The overall survival rate and local control rate for lung metastasis cases from lung cancer at 2 years after treatment were 81.5% and 92.4%, respectively, and 65.0% and 92.0% regarding lung metastasis from colorectal cancer. Carbon ion beam therapy for the metastatic lung tumors is a safe therapy, and the therapeutic effect is comparable to the outcome obtained from reported surgical resections