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Aims Cryoballoon ablation (CBA) is effective for atrial fibrillation (AF), however acute silent cerebral infarction (SCI) is not uncommon after CBA. This study aimed to clarify the relationship between the morphology of LAA and SCI. Methods and results From 2015 to 2019, 207 consecutive patients (65.1±11.4 years, 26.6% of female, 31.4% of persistent AF) who underwent CBA for AF at our hospital were enrolled. All patients were evaluated with computed tomography for LAA before CBA and divided into two groups as chicken wing (CW) group and non-CW group. SCI was evaluated with magnetic resonance imaging at the following day after CBA. As a result, 18.4% of patients have occurred SCI after CBA. Although the patients' background didn't differ between the two groups, the Hounsfield scale (LAA/Aorta ratio) was lower (non-CW vs. CW = 0.68±0.12 vs. 0.73±0.11, p=0.004), and LAA orifice size tended to be larger (16.9±4.6 vs. 15.8±4.1, p=0.053) in non-CW group. SCI significantly occurred in non-CW group (29.5% vs. 11.6%, p=0.003), especially in cauliflower shape of 45.0%. In multivariate analysis, non-CW (p=0.002, Odds ratio 3.2, 95% of CI 1.5–7.0), skipped DOAC before CBA (p=0.04, Odds ratio 6.1, 95% of CI 1.1–115.4), and touch-up ablation in left atrium (p=0.02, Odds ratio 2.8, 95% CI 1.2–6.5) were independent predictors of SCI. Conclusions SCI was not rare after CBA for AF. Morphology of LAA was strongly associated with SCI. Funding Acknowledgement Type of funding source: None

Background Although Right Ventricular dysfunction (RVD) is one of the predictor of poor prognosis, it is believed that ischemic RVD after percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) restores quickly. Because right ventricular perfusion has more ischemic preconditioning compared with left ventricle, due to their complex perfusion system. However, little is known about the time courses of RVD after ACS-PCI andtheir prognosis. We evaluated the relationship between right ventricular branch slow flow phenomenon (RVB-SF) post ACS-PCI in right coronary artery (RCA) and RVD at 6–8 months follow-up. Method We retrospectively analyzed consecutive 82 patients who underwent PCI for ACS in proximal or mid portion of RCA from August 2011 to March 2018 in our institution. Finally, both baseline and follow-up data were obtained from 70 patients. We analyzed TIMI frame count (TFC) to confirm the presence of RVB-SF (TFC ≥40 frame) after PCI. We also analyzed right ventricular fractional area change (RVFAC) at baseline and follow-up using echocardiography to detect sustained RVD (RVFAC ≤35%). Result We divided the patients into two groups (RVB-SF: 36 patients, RVB non-SF: 34 patients). Patient clinical characteristics were similar in both groups (sex, age, risk factors, medication, onset to balloon time, left ventricular stroke volume, max creatine kinase). Baseline RVFAC and follow-up RVFAC was significantly smaller in RVB-SF than in RVB non-SF, respectively. (27.1±1.7% vs. 38.3±1.8%, 31.4±1.0% vs. 48.7±1.1%, P Conclusion RVB-SF findings after ACS-PCI for RCA could predict sustained RVD at mid-term follow-up, which may indicate future prolonged RVD.

Background Silent cerebral thromboembolism (CE) in catheter ablation for atrial fibrillation (AF) is not rare. Prior our study has reported lower incidence of silent CE in AF radiofrequency (RF) ablation using irrigated-tip catheter than conventional 4 or 8mm-tip catheter. In addition, the incidence of silent CE in AF ablation under direct oral anticoagulant (DOAC) was equivalent to continuous therapeutic warfarin. Recently pulmonary vein isolation (PVI) using cryoballoon (CB) has emerged as an alternative technique to RF ablation because some studies suggested that the efficacy for PVI by CB was equivalent to RF. However, incidence of silent CE in CB ablation under the use of DOAC is unknown. Objective We aimed to evaluate the incidence new silent CE in AF ablation using CB system compared with irrigated RF system under the use of DOAC. Methods 322 consecutive patients with paroxysmal or persistent AF (155 using CB system, 167 using RF system) who underwent the first AF ablation were taking DOAC more than one month prior to the procedure. Throughout AF ablation procedure, heparin was administered to maintain activated clotting time (ACT) between 300 and 400 seconds. Head MRI was performed in all patients within 24 hours after the procedure. Results In 14 (9.0%) patients using CB and in 20 (12.0%) patients using RF, head MRI showed new embolic lesions without neurological symptom (P=0.469). Although the amount of heparin during the procedure in group CB was significantly less than in group RF (16134±3125 U vs. 18689±5222 U; P Conclusions The incidence of silent CE in AF ablation using CB system was lower than RF system, although it was not a significant difference between different ablation techniques for AF. In AF ablation, the use of CB may be preferred rather than RF as ablation system in regard to risk reduction of thromboembolic complications.

Background Dual-antiplatelet therapy (DAPT) after second-generation drug eluting stent (2-DES) implantation reduced the risk of stent thrombosis and subsequent ischemic events, with an increase in bleeding risk. Although chronic kidney disease patients have high ischemic and bleeding risk, little is known about both risks in hemodialysis patients after 2-DES implantation during DAPT. Method From July 2009 to March 2017, we retrospectively analyzed post-discharge major adverse cardiac and cerebrovascular events [MACCE: cardiac death, myocardial infarction, target vessel revascularization (TVR) and cerebral infarction] and bleeding events in 644 consecutive patients during DAPT after 2-DES implantation. We divided them into 2 groups [102 hemodialysis (HD) and 518 non-hemodialysis (Non-HD) patients, mean age, 71±10 years] after excluding 24 patients (lost to follow up and peritoneal dialysis). Follow-up period was 49±24 months. Median DAPT duration was 12 months. The primary endpoint was MACCE. The secondary endpoint was bleeding events according to the Bleeding Academic Research Consortium (BARC) type 2, 3, or 5. MACCE and bleeding events were compared between HD and Non-HD by using the propensity score-matching (PSM) method. Results Among the 620 eligible patients, the primary and secondary events occurred in 207 (33.3%) and 76 (12.3%) patients, respectively. The rates of unadjusted MACCE [HD vs Non-HD: 53.9% vs 29.3%; Hazard ratio (HR) 2.39, p After 1-to-1 propensity score adjustment for baseline differences (hypertension, diabetes mellitus, low ejection fraction, low albumin, anemia, and high C-reactive protein), a total of 160 patients (80 HD vs 80 Non-HD) was created. The rate of MACCE [HD vs Non-HD: 52.5% vs 31.3%; adjusted HR 2.04, p Conclusions As a result of PSM, HD was shown to contribute to ischemic risk rather than bleeding risk. Even in the 2-DES era, HD was an independent risk factor of cardiac death and TVR. Therefore, further study on the current regimen of DAPT would be necessary while balancing both ischemic and bleeding risk.

Background Because soluble (or secreted) amyloid precursor protein-β (sAPPβ) and -α (sAPPα) possibly reflect pathological features of Alzheimer’s disease (AD), they are potential biomarker candidates for dementia disorders, including AD and mild cognitive impairment (MCI) due to AD (MCI-AD). However, controversial results have been reported regarding their alterations in the cerebrospinal fluid (CSF) of AD and MCI-AD patients. In this study, we re-assessed the utility of sAPPα and sAPPβ in CSF as diagnostic biomarkers of dementia disorders. Methods We used a modified and sensitive detection method to analyze sAPPs levels in CSF in four groups of patients: AD (N = 33), MCI-AD (N = 17), non-AD dementia (N = 27), and disease controls (N = 19). Phosphorylated tau (p-tau), total tau, and Aβ42 were also analyzed using standard methods. Results A strong correlation was observed between sAPPα and sAPPβ, consistent with previous reports. Both sAPPα and sAPPβ were highly correlated with p-tau and total tau, suggesting that sAPPs possibly reflect neuropathological changes in the brain. Levels of sAPPα were significantly higher in MCI-AD cases compared with non-AD and disease control cases, and those of sAPPβ were also significantly higher in MCI-AD and AD cases relative to other cases. A logistic regression analysis indicated that sAPPα and sAPPβ have good discriminative power for the diagnosis of MCI-AD. Conclusions Our findings collectively suggest that both sAPPs are pathologically relevant and potentially useful biomarkers for early and accurate diagnosis of dementia disorders. We also suggest that careful measurement is important in assessing the diagnostic utility of CSF sAPPs. Electronic supplementary material The online version of this article (10.1186/s40364-017-0108-5) contains supplementary material, which is available to authorized users.

Summary Introduction It is well recognized that examinations of activated platelets (aPLTs) and platelet-activating capacity are very important to observe and prevent embolic diseases (events) such as ischemic stroke and myocardial infarction. Previously, we reported an appropriate measurement technique of aPLT for clinical assay. In this paper, we investigated stable conditions for measurement of activating capacity of platelets. Methods Blood samples were taken from healthy volunteers using anticoagulants of 2K-EDTA, sodium citrate and heparin, and platelets were stimulated with adenosine diphosphate (ADP) or collagen. We demonstrated platelet-activating capacity by detection of scattering light, absorbance, microscopic observation, and P-selectin (CD62P) expression. We also performed basic experiments in seven healthy volunteers to test the clinical application of these assays with monitoring aspirin therapy. Results We judged that samples of whole blood with 2K-EDTA were suitable for CD62P expression assay as functional assessments of platelet activity, because platelets treated with anticoagulants such as sodium citrate and heparin were extremely damaged after stimulation, and it was difficult to measure the CD62P expression by flow cytometry. For optimal results, samples should be tested within 1 h after the drawing of blood and stimulated with ADP or collagen for 10 min. The CD62P-positive platelet value of blood from volunteers who had taken aspirin was decreased, and platelet activation was inhibited as well. Conclusion The simultaneous assay of aPLT and platelet-activating capacity by CD62P detection using whole blood treated with the K2-EDTA anticoagulant was useful for the monitoring of antiplatelet drugs.

Background and study aim A prototype forward-viewing instrument has been developed for therapeutic endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA). We had the opportunity to use this forward-viewing echo endoscope and to study its clinical usefulness, mainly for diagnostic EUS-FNA. Patients and methods The prototype forward-viewing echo endoscope was used for 15 months between November 2006 and March 2010, in a study group comprising 47 consecutive patients. Diagnostic EUS-FNA was done in 38 patients and the diagnostic accuracy of the forward-viewing device was compared with that from an oblique-viewing echo endoscope in reference patients who were matched by disease and puncture route. Therapeutic EUS was done in nine patients (pseudocyst drainage in six; celiac ganglia neurolysis, biliary drainage, and pancreatic duct drainage in one each). Results Diagnostic EUS-FNA provided a correct diagnosis in 97.4 % (37/38 patients), which was not significantly different from the 94.7 % (36/38) in the reference patients. Lesions considered difficult to access with an oblique-viewing scope, such as those located at the fornix, or the head of the pancreas, or associated with strictures, were easily punctured, as were those located at the body or tail of the pancreas or at the porta hepatis. Treatment was successful in all nine patients who underwent therapeutic EUS procedures. None of the 47 patients had any complications. Conclusions A forward-viewing echo endoscope that allows target sites to be punctured more perpendicularly with minimal effort, can be used for diagnostic EUS-FNA and this may be advantageous, depending on the site of target lesions.

We evaluated the effects of a substrate in the biosynthesis of nitric oxide (NO)-l-arginine (LARG)-on hepatic lesions caused by ischemia/reperfusion (I/R) injury in rabbit livers. Rabbits were pretreated with LARG (150 mg/kg IV) or saline solution 0.9% (SS) before the hepatic I/R procedure. The effects of LARG on hepatic injury were evaluated before and after I/R. The warm hepatic I/R procedure produced profound acute liver injury, as indicated by elevated values of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactic dehydrogenase (LDH), as well as a high apoptotic cell count. All changes were attenuated by treatment with LARG before the hepatic I/R procedure. These results suggested that LARG produced protective effects on hepatic I/R lesions. This protective effect of LARG was probably associated with blocking generation of superoxide anions during the hepatic I/R procedure.

We examined the effects of acute exercise on reaction time to visual stimuli presented in the central portion and periphery of the visual field. Twelve participants performed reaction time tasks at rest and during cycling at 65 % peak oxygen uptake in two visual conditions. We used circular black-and-white checkerboard patterns as visual stimuli. The participants were asked to respond as quickly as possible to pattern reversal of the visual stimulus by releasing a response button. Reaction time was fractionated into Premotor time and Motor time. Premotor time in the peripheral condition significantly increased (p < 0.025) during exercise (mean +/- SE; 195.9 +/- 7.9 ms) from that at rest (183.7 +/- 6.8 ms). Premotor time in the central condition did not differ between at rest (185.3 +/- 7.6 ms) and during exercise (188.4 +/- 6.6 ms). These data suggest that the ability to respond to visual stimuli presented in the periphery of the visual field is vulnerable to moderate to severe exercise, as compared with the ability to respond to visual stimuli presented in the central portion of the visual field. An exercise-induced increase in arousal level and a consequent narrowing of attentional focus would explain the present results.

Wireless ATM is receiving a significant attention as a solution for wireless access. The integration of wireless access and ATM is an essential requirement for the future of telecommunications so that emerging wideband services which embody multimedia applications can be made transparently available to mobile terminals. There are many ongoing activities within the European ACTS program (Advanced Communications Technologies and Services) which are related to evolving ATM oriented wireless networks at various frequencies such as 5, 17, 40 and 60 GHz. AWACS (ATM Wireless Access Communication System) is one of these projects and addresses the feasibility of low cost, high-data-rate radio LAN systems based on ATM (both indoor and outdoor) at 19 GHz. This article overviews the AWACS project which has contributed to the definition of emerging European radio LAN standards such as ETSI BRAN HIPERLINK.

The Schottky barrier diode remains an important device for detecting and mixing at terahertz frequencies, particularly in plasma diagnostics and atmospheric remote sensing. In plasma diagnostics, plasma density is monitored using a receiver with an IF typically below 10 MHz, thus it is critical to reduce low-frequency excess noise to improve sensitivity. We present here a submicrometer Pt/GaAs diode fabrication process that has resulted in a significant reduction in low-frequency noise over that of commercially available devices. Noise performance is optimized by establishing an even distribution of gallium and arsenic (stoichiometric surface) at the contact surface. The effects of different SiO/sub 2/ deposition and etching techniques are also compared. Diodes fabricated with the optimized procedure have exhibited a signal-to-noise ratio that is three times higher than that of commercially available diodes at 0.9 THz using an IF of 80 kHz, as well as competitive performance at 1.4 THz with an IF in the gigahertz range.

Cu1.96S, Cu3Se2,αCu2Se, and Ag2Se were prepared by irradiating mixturs of the elements in methanol with ultrasound at 28 kHz, using a commercial ultrasonic cleaner. Scanning electron microscopy and electron probe microanalyis investigations on Cu3Se2showed that the compositions of both Cu and Se particles changed continuously to Cu3Se2as the irradiation time increased.

In a noncellular or large cell-size mobile radio communication system, log-normal shadowing as well as Rayleigh fading becomes the predominant source of system degradation. This paper proposes an efficient stop and wait automatic repeat request (SAW-ARQ) protocol with adaptive packet length to provide reliable mobile data packet transmission. The adaptive SAW-ARQ protocol controls the transmitting packet length according to the time-varying channel condition estimated with the number of ACK (acknowledgment packet) and NACK (negative-acknowledgment packet). Computer simulation results show that the proposed protocol can achieve high throughput and reduce the number of retransmission effectively for slow and fast Rayleigh fading/log-normal shadowing conditions.

The measures for orbital debris problems should be considered from both technical and social standpoints as well as in the context of their combination. This study provides an analysis of economic and political aspects associated with the space debris issues, with the aim at serving as a first step in Japan toward global discussions on healthy utilization of space as a common heritage for all humankind. This paper consists of two parts. First, cost estimates concerning four types of debris mitigation techniques are provided. Second, possible regulatory approaches to the debris problems on an international basis are discussed. These analyses are primarily based on the study performed by the Social Impact Subgroup of the Space Debris Study Group which was established within the Japan Society for Aeronautical and Space Sciences.

Mitsubishi Heavy Industries, Ltd. (MHI) developed a 1100°C class D-type gas turbine in the 1980s and constructed the world’s first successful large-scale combined cycle power plant. Since then, MHI has developed the F and G-type gas turbines with higher turbine inlet temperature and has delivered these units worldwide accumulating successful commercial operations. MHI is currently participating in a Japanese National Project to promote the development of component technology for the next generation 1700°C class gas turbine. MHI recently developed a 1600°C class J-type gas turbine utilizing some of the technologies developed in the National Project. This paper discusses the history and evolution of MHI large frame gas turbine for power generation and the 1600°C class J-type gas turbine update, including the engine specification, verification and trial operation status.

In Japan, Japanese Black and Holstein cattle are appreciated as popular sources of meat, and imported beef from Australia and the United States is also in demand in the meat industry. Since the BSE outbreak, the problem of false sales has arisen: imported beef has sometimes been mislabeled as domestic beef due to consumer concerns. A method is needed to correctly discriminate between Japanese and imported cattle for food safety. The objective of this study was to develop breed discrimination markers between Japanese and US cattle using a 50K SNP array. As a result, five US-specific markers (BISNP7, BISNP15, BISNP21, BISNP23, and BISNP26) were developed with allelic frequencies that ranged from 0.102 (BISNP15) to 0.250 (BISNP7) and averaged 0.184. The combined use of the five markers would permit discrimination between Japanese and US cattle with a probability of identification of 0.858. This result indicates the potential of the bovine 50K SNP array as a powerful tool for developing breed identification markers. These markers would contribute to the prevention of falsified beef displays in Japan.

The purpose of this study was to investigate the effect of intensive eccentric exercise on hamstring muscles by using magnetic resonance imaging (MRI) and to elucidate the relationships between the changes in the electromyographic (EMG) parameters and in the transverse relaxation time (T2) of the hamstring muscles. Seven male volunteers performed eccentric knee flexion exercise, and the EMG activity of the hamstring muscles was simultaneously measured. Before and immediately after the exercise, the maximum isometric knee flexion torque was measured and MR images of the hamstring muscles were obtained. For all hamstring muscles, the EMG activity of the fifth set was significantly lower than that of the first set. For each subject, a significant correlation was detected between the percentage change in the value of the post-exercise T2 value and those of EMG signals during the exercise only for the semitendinosus (ST) muscle and not for the biceps femoris (BF) and the semimembranosus (SM) muscles. These results suggested that the EMG-activity reductions in the BF, ST, and SM muscles were due to neuromuscular fatigue, and moreover the reduction in the ST muscle was due to a failure in the E-C coupling, which was caused by excessive muscle-fiber damage.

In this paper, we report two evaluation results of ASR (automatic speech recognition) for a car navigation system, first interface evaluation results using a commercial product and second ASR module evaluation results for noisy in-car speech. In the first evaluation, we report many undesirable OOV (Out Of Vocabulary) utterances which make the interface worse. To overcome this problem, we propose a sophisticated interface which can handle OOV problems. Next, we carried out ASR module evaluation for the noisy in-car real speech gathered using driving car. We used free Continuous Speech Recognition (CSR) software Julius/Julian as a speech decoder.

A case of odontogenic myxoma is reported as showing a cyst-like pattern with a partially thick but vague and unclear radiopaque border between the left mandibular second premolar and first molar on rotational panoramic radiography. Internal structure of the lesion displayed radiolucency with a sparse and coarse trabecular pattern. No expansion of bucco-lingual cortical bone was apparent. The radiographic pattern of odontogenic myxoma did not resemble a tennis racket-like or straight, curved and coarse septal appearance on panoramic radiography, but characteristic findings were noted on cone beam CT. Cone beam CT may prove extremely useful in clarifying detailed internal structure and the state of margins.

This paper introduces an intelligent K-band speedometer sensor (KBSS) for ETC (electronic toll collection) system, that is applicable to ad-hoc networks. New and high-precision speedometer sensors have been installed in mobile nodes (vehicles) and on ETC terminals network using K-band Doppler and K-band FMCW (frequency modulated continuous wave) technology, respectively. The ETC network and mobile nodes are organized in an ad hoc manner. The new speedometer sensor is small, inexpensive and low-power device based on the Doppler effects phenomenon to obtain a speed of the vehicle more precisely. The ETC system is capable to locate the position of the vehicles within a long distance from ETC area and without the vehicles even having to slow down during they approach to the ETC gates. The experimental design, data collection and data evaluations are discussed, and the features of the new system have been appraised and compared with a conventional speedometer. The results show that our new speedometer development exhibits a phenomenal performance gains with low cost design, light weight and its performance provides a pragmatic element for emerging ITS infrastructure.

In multihop wireless networks, the quality of communications is degraded due to the relay transmissions over fading channels. Space-time code using multiple transmit antennas is an effective countermeasure for fading. For terminals which have only one antenna due to size/cost limitations, user cooperation has been introduced as a diversity technique. A new cooperative relaying scheme is proposed in order to combat the effects of fading in multihop communications among single antenna terminals. This scheme utilizes space-time code for cooperative relaying and is developed in both frequency-flat and frequency-selective fading channels for exploiting space and path diversity gain. By computer simulations, it is shown that the scheme can achieve almost full spatial diversity in multihop communications by both non-regenerative relaying with SNR estimation and regenerative relaying with error detection.