Electrostatically-sprayed carbon electrodes for high performance organic complementary circuits.

Organic thin-film transistors (OTFTs) are promising building blocks of flexible printable electronic devices. Similar to inorganic FETs, OTFTs are heterostructures consisting of metals, insulators, and semiconductors, in which nanoscale interfaces between different components should be precisely engineered. However, OTFTs use noble metals, such as gold, as electrodes, which has been a bottleneck in terms of cost reduction and low environmental loading. In this study, we demonstrate that graphite-based carbon electrodes can be deposited and patterned directly onto an organic single-crystalline thin film via electrostatic spray coating. The present OTFTs exhibited reasonably high field-effect mobilities of up to 11 cm2 V-1 s-1 for p-type and 1.4 cm2 V-1 s-1 for n-type with no significant deterioration during electrostatic spray processes. We also demonstrate two significant milestones from the viewpoint of material science: a complementary circuit, an inverter consisting of p- and n-type OTFTs, and an operatable metal-free OTFT composed of fully carbon-based materials. These results constitute a key step forward in the further development of printed metal-free integrated circuits.

Relationship between salt intake and sleep disordered breathing in dialysis patients.

BACKGROUND: The prevalence of sleep disordered breathing is high in patients with end-stage renal disease. Salt intake is related to the severity of obstructive sleep apnea in patients with resistant hypertension and hyperaldosteronism. We investigated the relationship between salt intake and sleep disordered breathing in patients on maintenance hemodialysis. PATIENTS AND METHODS: We studied 128 dialysis outpatients (mean age 63 ± 11 years) who were followed at Kokura Daiichi Hospital. We estimated each patient's salt intake using an InBody S10 body composition analyzer and measured the 3% oxygen desaturation index (ODI) during sleep using a Pulsewatch: PMP-200 GplusX. RESULTS: The average estimated salt intake was 8.0 ± 2.6 g/day, and the median value of that was 7.5 g/day. Blood pressure (BP) before and after dialysis were 140 ± 18/78 ± 11 and 127 ± 13/72 ± 8 mmHg, respectively. The geometric average number of 3% ODI was 7.1, and sleep disordered breathing was detected in 30% of all subjects. The patients with ≥ 7.5 g/day salt intake were younger and more frequently male and had higher body mass index (BMI) and BP before dialysis compared to those with salt intakes < 7.5 g/day. Patients with ≥ 7.5 g/day salt intake had a significantly higher geometric average number of 3% ODI; however, this relationship became weaker after adjusting for BMI. The same relationship was obtained for the prevalence of sleep disordered breathing. CONCLUSION: The prevalence of sleep disordered breathing in patients on maintenance hemodialysis was high, and the sleep disordered breathing was associated with salt intake and BMI.

Net-400-Gbps PS-PAM transmission using integrated AMUX-MZM.

Simple high-speed optical transmission technologies are desired for use in intra-and inter-datacenter networks. In this study, we demonstrate simple single-carrier intensity-modulated direct-detection (IMDD) transmissions at a net data rate of 400 Gbps (516.7 Gbps gross) over 20 km with a compact transmitter subassembly. The subassembly consists of a 2:1 analog multiplexer (AMUX) and an InP Mach-Zehnder modulator (MZM) placed close to each other and connected via wires. We employed 162-Gbaud single-carrier probabilistically shaped pulsed amplitude modulation (PS-PAM). The baseband signals with a bandwidth of around 81 GHz to drive the MZM were generated by a super-digital-to-analog converter (super-DAC) consisting of two sub-DACs and the AMUX. Digital nonlinear pre-distortion enabled us to transmit the signals with normalized generalized mutual information (NGMI) larger than the threshold of a soft-decision forward error correction (SD-FEC) code of 0.857. Truncation of the PS-PAM symbol distribution further enhanced performance. To the best of our knowledge, this is the first net-400-Gbps single-carrier IMDD transmission using a compact transmitter subassembly.

Ultra-compact coherent receiver with serial interface for pluggable transceiver.

An ultra-compact integrated coherent receiver with a volume of 1.3 cc using a quad-channel transimpedance amplifier (TIA)-IC chip with a serial peripheral interface (SPI) is demonstrated for the first time. The TIA with the SPI and photodiode (PD) bias circuits, a miniature dual polarization optical hybrid, an octal-PD and small optical coupling system enabled the realization of the compact receiver. Measured transmission performance with 32 Gbaud dual-polarization quadrature phase shift keying signal is equivalent to that of the conventional multi-source agreement-based integrated coherent receiver with dual channel TIA-ICs. By comparing the bit-error rate (BER) performance with that under continuous SPI access, we also confirmed that there is no BER degradation caused by SPI interface access. Such an ultra-compact receiver is promising for realizing a new generation of pluggable transceivers.

Impact of clinical and echocardiographic characteristics on occurrence of cardiac events in cardiac amyloidosis as proven by endomyocardial biopsy.

BACKGROUND: Although patients with immunoglobulin light chain (AL) cardiac amyloidosis exhibit worse outcomes than those with transthyretin (TTR) cardiac amyloidosis, few data exist regarding the occurrence of cardiac events and the echocardiographic indices in endomyocardial biopsy (EMBx) proven amyloidosis. METHODS: From November 2007 to October 2012, we identified 33 patients with EMBx-proven amyloidosis. There were 12 patients (8 men; mean age: 66 years) with AL and 21 patients (20 men; mean age: 78 years) with TTR. We performed serial echocardiography and observed the patients during follow-up; defining all-cause mortality as the primary endpoint and hospitalization for heart failure as the secondary endpoint. RESULTS: The survival rates at 12 months were 20.8% and 85.7% in AL and TTR, respectively (p<0.001). The cumulative incidences of the composite of death or readmission for heart failure at 12 months were 91.7% and 51.3% in AL and TTR, respectively (p<0.001). A multivariate analysis showed that the AL type amyloid was the powerful predictor of mortality (hazard ratio: 8.50, 95% confidence interval: 1.79 to 40.57, p<0.05). Under these conditions, the E/e' in AL tended to increase from 23±13 to 28±11 (p=0.06) with marked increases in B-type natriuretic peptide (779±456 pg/ml to 1576±895 pg/ml, p<0.05), although these remained unchanged in TTR, which exhibited significantly increased left ventricular end-diastolic dimensions from 40±4 mm to 42±4 mm (p<0.05). CONCLUSIONS: The survival rate was generally worse in AL cardiac amyloidosis, although the readmission for heart failure remains high in TTR cardiac amyloidosis with the occurrence of left ventricular dilatation.

In-band OSNR monitor with high-speed integrated Stokes polarimeter for polarization division multiplexed signal.

An in-band optical signal-to-noise ratio (OSNR) monitor is proposed, based on an instantaneous polarization state distribution analysis. The proposed monitor is simple, and is applicable to polarization division multiplexed signals. We fabricate a high-speed Stokes polarimeter that integrates a planar lightwave circuit (PLC) based polarization filter, high-speed InP/InGaAs photodiodes and InP hetero-junction bipolar transistor (HBT) trans-impedance amplifiers (TIA). We carry out proof-of-concept experiments with the fabricated polarimeter, and successfully measure the OSNR dependent polarization distribution with 100-Gb/s dual polarization quadrature phase shift keying (DP-QPSK) signals.

Incidence and clinical impact of stent fracture after everolimus-eluting stent implantation.

BACKGROUND: Stent fracture (SF) after drug-eluting stent implantation has recently become an important concern because of its potential association with in-stent restenosis and stent thrombosis. However, the incidence and clinical impact of SF after everolimus-eluting stent implantation remain unclear. METHODS AND RESULTS: A total of 1035 patients with 1339 lesions undergoing everolimus-eluting stent implantation and follow-up angiography 6 to 9 months after index procedure were analyzed. SF was defined as complete or partial separation of the stent, as assessed by plain fluoroscopy or intravascular ultrasound during follow-up. We assessed the rates of SF and major adverse cardiac events, defined as cardiac death, myocardial infarction, stent thrombosis, and clinically driven target lesion revascularization within 9 months. SF was observed in 39 of 1339 lesions (2.9%) and in 39 of 1035 patients (3.8%). Ostial stent location and lesions with hinge motion, tortuosity, or calcification were independent predictors of SF. The rate of myocardial infarction and target lesion revascularization were significantly higher in the SF group than in the non-SF group (5.1% versus 0.4%; P=0.018 and 25.6% versus 2.0%; P<0.001, respectively). Stent thrombosis was more frequently observed in the SF group than in the non-SF group (5.1% versus 0.4%; P=0.018). Major adverse cardiac events within 9 months were significantly higher in the SF group than in the non-SF group (25.6% versus 2.3%; P<0.001). CONCLUSIONS: SF after everolimus-eluting stent implantation occurs in 2.9% of lesions and is associated with higher rate of major adverse cardiac events, driven by higher target lesion revascularization and stent thrombosis.

Bare metal stent thrombosis and in-stent neoatherosclerosis.

BACKGROUND: Very late stent thrombosis (VLST) was reported to occur even in patients with bare metal stent (BMS) implantation, although the annual incidence of VLST after BMS was much lower than that after drug-eluting stent implantation. Pathophysiologic mechanisms of VLST after BMS implantation remain largely unknown. METHODS AND RESULTS: From September 2002 to February 2010, we identified 102 patients with definite stent thrombosis (ST) of BMS and 42 control patients with acute coronary syndrome (ACS) unrelated to ST who underwent thrombus aspiration with histopathologic evaluation. There were 40 patients with early ST (EST, within 30 days), 20 patients with late ST (LST, between 31-365 days), and 42 patients with VLST (>1 year). Evidence for fragments of atherosclerotic plaques, such as foamy macrophages, cholesterol crystals, and thin fibrous cap, was more commonly seen in patients with EST (23%) and VLST (31%), whereas these findings were rarely observed in patients with LST (10%). Atherosclerotic fragments were predominantly seen in patients who had EST within 7 days or VLST beyond 3 years. The aspirated thrombi harvested from patients with ST and those with ACS were histologically indistinguishable from each other. Eosinophils were very rarely observed. Plasma level of total cholesterol and triglyceride were significantly higher in VLST cases with atherosclerotic fragments as compared with those without. CONCLUSIONS: Fragments of atherosclerotic plaque were highly prevalent in patients with VLST beyond 3 years. Disruption of in-stent neoatherosclerosis could play an important role in the pathogenesis of VLST of BMS occurring beyond 3 years after implantation.

Primary percutaneous coronary intervention for acute myocardial infarction in the elderly aged ≥75 years.

OBJECTIVES: We aimed to see whether primary percutaneous coronary intervention (PCI) benefits for ST-segment elevation myocardial infarction (STEMI) in the aged could be validated. BACKGROUND: Primary PCI benefits in elderly patients with STEMI remain uncertain. METHODS: We reviewed 947 consecutive patients treated with primary PCI for STEMI: 331 were aged ≥75 years (older) and 616 <75 years (younger). RESULTS: The older group had higher percentage of renal insufficiency (7.9% vs. 3.1%, P = 0.0010), prior stroke (9.4% vs. 3.9%, P = 0.0006), 30-day mortality rate (7.6% vs. 3.9%, P = 0.015), and cardiac mortality rate (6.6% vs. 3.7%, P = 0.045). Successful reperfusion rates were similarly high in both groups (90.0% and 92.7%, P = 0.16), despite the higher proportion of patients with door-to-balloon time >90 min (15% vs. 8.4%, P = 0.0016) in older patients. Successful compared with unsuccessful PCI significantly decreased 30-day mortality rates in the older group (6.0% vs. 21%, P = 0.0018) and in the younger group (2.8% vs. 18%, P < 0.0001). When reperfusion was successful, cardiac mortality rate in older patients was not significantly greater than in younger patients (5.4% vs. 2.8%, P = 0.057). By multivariate analysis, unsuccessful reperfusion independently predicted 30-day mortality (odds ratio, 4.04; 95% confidence interval, 1.79-9.12; P = 0.0008), whereas age ≥75 years (odds ratio, 1.00; 95% confidence interval, 0.41-2.41; P = 0.99) and door-to-balloon time >90 min (odds ratio, 1.78; 95% confidence interval, 0.76-4.20; P = 0.19) did not. CONCLUSIONS: Pre-existing comorbidities characterize older patients developing STEMI. Aggressive PCI in older patients improves prognosis, and short door-to-balloon time is an important parameter conditioning the prognosis.

Very long-term (15 to 23 years) outcomes of successful balloon angioplasty compared with bare metal coronary stenting.

BACKGROUND: Target lesion revascularization (TLR) continues to occur beyond 4 years after bare metal stent (BMS) implantation. However, long-term outcomes after balloon angioplasty (BA) compared with BMS are currently unknown. METHODS AND RESULTS: From 1989 to 1990, 659 patients (748 lesions) underwent successful BA with final balloon ≥3.0 mm excluding patients with acute myocardial infarction and were compared with 405 patients (424 lesions) with BMS implantation from June 1990 to 1993. Cumulative incidences of death and target lesion thrombosis (>1 year) were similar between the BA group and the BMS group (44.4% versus 45.4%, P=0.60; and 1.5% versus 0.7%, P=0.99; respectively). Cumulative incidence of TLR during overall follow-up was significantly higher after BA than after BMS implantation (44.6% versus 36.0%, P<0.001), whereas cumulative incidence of late TLR (>4 years) tended to be lower in the BA group than in the BMS group (16.3% versus 21.4%, P=0.16). Cumulative incidence of late TLR after BA was significantly lower in patients with small percent diameter stenosis (%DS) at early follow-up angiography compared with large %DS (14.5% versus 28.0%, P=0.02). In lesions with serial angiography, late lumen loss from early (6 to 14 months) to long-term (4 to 10 years) follow-up angiography was significantly smaller in the BA group (n=42) than in the BMS group (n=55) (-0.08±0.45 mm versus 0.11±0.46 mm, P=0.047). CONCLUSIONS: Compared with BMS implantation, BA was associated with a trend for less late TLR beyond 4 years and with significantly smaller late lumen loss from early to long-term follow-up angiography.

100-Gbit/s PDM-QPSK coherent receiver with wide dynamic range and excellent common-mode rejection ratio.

We report the design and fabrication of a hybrid-integration-type coherent receiver. We optimize the receiver building blocks, and achieve a -25-dB common-mode rejection ratio and a 20-dB signal input power dynamic range.

Very long-term (15 to 20 years) clinical and angiographic outcome after coronary bare metal stent implantation.

BACKGROUND: We previously reported that the long-term luminal response after coronary bare metal stenting is triphasic, with an early restenosis phase spanning the 6 months after the index procedure, an intermediate-term regression phase from 6 months to 3 years, and a late renarrowing phase beyond 4 years. However, the clinical significance of late luminal renarrowing remains unknown. METHODS AND RESULTS: Angiographic and clinical follow-up of the same cohort of 405 patients with successful Palmaz-Schatz stent placement was extended beyond 15 years. Clinical follow-up was completed in 98% of patients at 5 years and in 81% at 15 years. The incidence of death and cardiac death at 15 years was 45.4% and 20.6%, respectively. Paired long-term (4 to 10 years) and very long-term (>10 years) angiographic studies without intercurrent target lesion revascularization were performed in 55 lesions, and minimal luminal diameter further decreased from 1.88±0.50 mm to 1.60±0.73 mm (P=0.002). Late target lesion revascularization after initial stabilization of the stented segments occurred rarely within 4 years. Beyond 4 years, however, the incidence of late target lesion revascularization increased steadily from 3.3% at 4 years to 24.7% at 15 years. The incidence of definite very late stent thrombosis was low (1.5% at 15 years). CONCLUSIONS: Luminal renarrowing of the stented segment beyond 4 years was a progressive process extending beyond 10 years. The angiographic observation of late in-stent restenosis was clinically relevant because a corresponding progressive increase in the incidence of late target lesion revascularization was observed beyond 4 years and up to 15 to 20 years after bare metal stent implantation.

Impact of multiple and long sirolimus-eluting stent implantation on 3-year clinical outcomes in the j-Cypher Registry.

OBJECTIVES: Our aim was to study the relationships between total stent length (TSL) and long-term clinical outcomes after sirolimus-eluting stent (SES) implantation. BACKGROUND: SES compared with bare-metal stent use for long lesion treatment is associated with reduced restenosis rates. METHODS: Three-year follow-up data were available for 10,773 patients (14,651 lesions) that had been treated with only SES (Cypher, Cordis Corp., Warren, New Jersey) in the j-Cypher registry. Patients and lesions were divided into quartile groups: TSL per patient (Q1: 8 to 23 mm, Q2: 24 to 36 mm, Q3: 37 to 54 mm, Q4: 55 to 293 mm), and TSL per lesion (QA: 8 to 18 mm, QB: 19 to 23 mm, QC: 24 to 33 mm, QD: 34 to 150 mm). RESULTS: In per-lesion data, longer TSL increased target lesion revascularization (TLR) rates but did not increase stent thrombosis rates (p = 0.2324). In per-patient data, the incidences of TLR remarkably increased with increasing TSL. Incidence of composite of death and myocardial infarction also increased with increasing TSL; however, after adjustment for baseline differences, there was no statistical significance. Definite stent thrombosis rate in group Q4 was significantly higher than in other groups, both unadjusted (hazard ratio: 1.770, p = 0.0081) and adjusted (hazard ratio: 1.727, p = 0.0122) for baseline differences. CONCLUSIONS: TSL per lesion and patient had significantly impacts on TLR rates. Longer TSL per patient was associated with increased incidence of stent thrombosis through 3 years.

Efficacy of coronary venoplasty for left ventricular lead implantation.

BACKGROUND: Optimal target vein selection for the pacing lead results in a better outcome, but left ventricular (LV) variability limits this selection. The aim of the present study was to investigate the efficacy of coronary venoplasty for insertion of a LV lead. METHODS AND RESULTS: Transvenous LV lead placement was attempted in 208 consecutive patients from November 2002 to January 2007, with success in 206 patients (99%). Retrospective analysis of the cardiac resynchronization therapy system implantation showed that 4 of the 206 patients (1.9%) required coronary venoplasty for insertion of the pacing lead implant. Using coronary balloon angioplasty catheters of 2.5 mm (2 patients), 3.0 mm (1 patient) and 4.0 mm (1 patient), each target vein was dilated. Of 4 patients, stenoses in 3 were dilated by balloon angioplasty only. However, focal stenosis of 1 patient was not able to be dilated due to severe stenosis. Therefore, part of the lesion was sharpened by rotational atherectomy and the stenosis was successfully dilated. The LV pacing lead could then be inserted and no complications occurred. CONCLUSION: Venoplasty for stenosis was effective in allowing deployment of a LV lead into a target vein in some patients. The safety and complications of the procedure remain unclear.

Comparison of 30-day outcomes in patients <75 years of age versus >or=75 years of age with acute myocardial infarction treated by primary coronary angioplasty.

We reviewed 1,087 consecutive patients treated by primary coronary angioplasty for acute myocardial infarction; 309 were >or=75 and 778 were <75 years of age. Compared with the younger group, the older group had higher 30-day (8.1% vs 4.0%, p = 0.0057) and cardiac (6.5% vs 3.6%, p = 0.038) mortality rates. Successful reperfusion was achieved in the 2 groups at a similarly high rate (91.6% and 92.9%, p = 0.45). Successful compared with unsuccessful angioplasty decreased 30-day mortality rates in the older group (6.0% vs 30.8%, p <0.0001) and in the younger group (3.2% vs 14.5%, p <0.0001). When reperfusion was successful, the cardiac mortality rate in older patients was not significantly greater than that in younger patients (4.6% vs 2.8%, p = 0.14). By multivariate analysis in all 1,087 patients, overt cardiogenic shock on admission (odds ratio 44.7, 95% confidence interval 22.0 to 91.1, p <0.0001) and unsuccessful reperfusion (odds ratio 9.40, 95% confidence interval 4.11 to 21.5, p <0.0001) were found to be independent predictors of 30-day mortality, whereas age >or=75 years (odds ratio 1.79, 95% confidence interval 0.91 to 3.50, p = 0.090) was not. In conclusion, aggressive angioplasty in older patients improves prognosis.

Efficacy of nifekalant hydrochloride in the treatment of fatal ventricular arrhythmia in patients with ischemic heart disease.

Ventricular tachycardia (VT), which causes hemodynamic instability, and ventricular fibrillation (VF) sometimes occur in patients with severe underlying cardiovascular disease such as myocardial ischemia or infarction, and are associated with high mortality. This report presents the efficacy of nifekalant hydrochloride (nifekalant), a pure class III antiarrhythmic agent, in treating life-threatening ventricular arrhythmia in such patients. From June 2000, when nifekalant became commercially available in Japan, to May 2003, 30 ischemic heart disease (IHD) patients with VT/VF resistant to direct-current (DC) countershock received nifekalant in our hospital. These 30 patients served as the nifekalant group in this study. As a control group, we also included 33 IHD patients with VT/VF that had been resistant to DC countershock upon or during hospitalization between January 1996 and May 2000 before nifekalant became commercially available. No significant differences were observed in patient background factors and treatments between the two groups. The rates of death within 48 hours of occurrence of VT/VF were significantly lower in the nifekalant group (7%, 2/30) than in the control group (27%, 9/33; P < 0.03). The rates of cardiac death during hospitalization were also significantly lower in the nifekalant group (40%, 12/30) than in the control group (67%, 22/33; P < 0.03). The rates of survival until hospital discharge were significantly higher in the nifekalant group (57%, 17/30) than in the control group (30%, 10/33; P < 0.03). Multivariate analysis of all 63 patients revealed nifekalant administration was the factor that significantly improved the mortality (odds ratio for cardiac death, 0.26; 95% confidence interval (CI), 0.07 to 0.95; P = 0.041). Nifekalant improves the prognosis for life-threatening ventricular arrhythmia in IHD patients.

Late restenosis of the balloon-dilated site: serial angiographic observations beyond 7 years.

BACKGROUND: The present retrospective study was performed to assess the long-term (>7 years) fate of stabilized balloon-dilated sites. METHODS AND RESULTS: Between February and April 1986, 171 patients underwent successful percutaneous balloon angioplasty. Early restenosis (<1 year) occurred in 53%, but repeat balloon angioplasty stabilized the balloon-dilated site. The early period was defined as 6 months, late years as 3-5 years and long-term years as 7-12 years. Angiographic evaluation at both early year or late year periods (mean = 4.7 years) and long-term (mean = 10.4 years) periods following stabilization was available in 71 patients (94 lesions) with mean age of 61.7+/-8.5 years. Of the 71 patients 69.6% were male. Restenosis occurring after 1 year was defined as late restenosis. The mean diameter stenosis changed from 6 months (50.3+/-12.4%) to late-period (44.2 +/-13.2%; p < 0.05) and long-term period (50.3+/-16.1%; p < 0.001); but the reference vessel diameter did not change significantly. Late restenosis occurred in 28% (3-5 years) and 33% (7-12 years) of 94 lesions, and 13.8% of lesion required repeat target lesion revascularization. During this period, 5.3% of patients (5 lesions) underwent revascularization for new proximal or distal lesions. CONCLUSIONS: Decrease of luminal diameter during the early 6 months, was followed by regression after stabilization of the balloon-dilated site up to 5 years, but luminal re-narrowing occurs again over 7 years after balloon angioplasty.

Initial and follow-up results of the BiodivYsio phosphorylcholine coated stent for treatment of coronary artery disease.

BACKGROUND: The BiodivYsio stent is coated with a phosphorylcholine containing copolymer to confer biocompatibility. The present study was designed to assess the safety and efficacy of this coronary stent for the treatment of native coronary artery lesions in patients with coronary artery disease. METHODS AND RESULTS: From August 2001 to April 2003, 130 patients with lesions were treated with this stent. Elective stenting (ES) was performed in 90 patients and bailout stenting (BS) was performed in 40 patients with small vessels. Pre-interventional reference diameter, minimal lumen diameter (MLD), and lesion length were 2.68+/-0.51, 1.00+/-0.30, 12.78+/-4.32, respectively, and post-interventional MLD was 2.24+/-0.45 mm. The initial success rate was 100%. However, 2 non-Q-wave myocardial infarctions (non-QMI) occurred post-procedurally due to branch occlusion. A 6-month follow-up was performed. No subacute thrombosis occurred. In the ES group, 1 non-QMI occurred after the interventional procedure in another vessel. There was no death or coronary artery bypass grafting (CABG). The angiographic restenosis rate was 15.6%. In the BS group, there was no death, myocardial infarction or CABG. The angiographic restenosis rate was 17.5%. CONCLUSION: The BiodivYsio stent is safe and effective as a primary device for the treatment of native coronary artery lesions, especially in small vessels.