Adaptive Synaptic Memory via Lithium Ion Modulation in RRAM Devices

Biologically plausible computing systems require fine-grain tuning of analog synaptic characteristics. In this study, lithium-doped silicate resistive random access memory with a titanium nitride (TiN) electrode mimicking biological synapses is demonstrated. Biological plausibility of this RRAM device is thought to occur due to the low ionization energy of lithium ions, which enables controllable forming and filamentary retraction spontaneously or under an applied voltage. The TiN electrode can effectively store lithium ions, a principle widely adopted from battery construction, and allows state-dependent decay to be reliably achieved. As a result, this device offers multi-bit functionality and synaptic plasticity for simulating various strengths in neuronal connections. Both short-term memory and long-term memory are emulated across dynamical timescales. Spike-timing-dependent plasticity and paired-pulse facilitation are also demonstrated. These mechanisms are capable of self-pruning to generate efficient neural networks. Time-dependent resistance decay is observed for different conductance values, which mimics both biological and artificial memory pruning and conforms to the trend of the biological brain that prunes weak synaptic connections. By faithfully emulating learning rules that exist in human's higher cortical areas from STDP to synaptic pruning, the device has the capacity to drive forward the development of highly efficient neuromorphic computing systems.

Light Trapping Induced High Short-Circuit Current Density in III-Nitride Nanorods/Si (111) Heterojunction Solar Cells

An effective-area photovoltaic efficiency of 1.27% in power conversion, excluding the grid metal contact area and under 1 sun, AM 1.5G conditions, has been obtained for the p-GaN/i-InGaN/n-GaN diode arrays epitaxially grown on (111)-Si. The short-circuit current density is 14.96 mA/cm2 and the open-circuit voltage is 0.28 V. Enhanced light trapping acquired via multiple reflections within the strain and defect free III-nitride nanorod array structures and the short-wavelength responses boosted by the wide bandgap III-nitride constituents are believed to contribute to the observed enhancements in device performance.

Folic acid ameliorates homocysteine-induced angiogenesis and portosystemic collaterals in cirrhotic rats

INTRODUCTION AND OBJECTIVES

Liver cirrhosis is characterized by increased intrahepatic resistance, splanchnic vasodilation/angiogenesis, and formation of portosystemic collateral vessels. Collaterals can cause lethal complications such as gastroesophageal variceal hemorrhage. Homocysteine is linked to vascular dysfunction and angiogenesis and higher levels have been reported in cirrhotic patients. It is also known that folic acid supplementation reverses the effects of homocysteine. However, the treatment effect in cirrhosis has yet to be investigated.

MATERIAL AND METHODS

Liver cirrhosis was induced in Sprague-Dawley rats with common bile duct ligation (CBDL). The CBDL rats randomly received (1) vehicle; (2) dl-homocysteine thiolactone (1g/kg/day); (3) dl-homocysteine thiolactone plus folic acid (100mg/kg/day); or (4) folic acid. On the 29th day, hemodynamic parameters, liver and renal biochemistry, protein expressions of proangiogenic factors, mesenteric vascular density and portosystemic shunting were evaluated.

RESULTS

In the cirrhotic rats, homocysteine increased mesenteric vascular density and the severity of shunting. It also up-regulated the protein expressions of mesenteric vascular endothelial growth factor (VEGF) and phosphorylated-endothelial nitric oxide synthase (p-eNOS). These effects were reversed by folic acid treatment (P<0.05).

CONCLUSION

Folic acid ameliorated the adverse effects of homocysteine in the cirrhotic rats, which may be related to down-regulation of the VEGF-NO signaling pathway.

A Randomized Controlled Trial of Transcultural Validation of Group-Based Psychosocial Intervention for Patients with Bipolar Disorder

Adjunctive psychosocial interventions are part of the preferred method to treat bipolar disorder (BD). This study aimed to conduct a randomized control and protocol-guided trial, in order to evaluate the feasibility and effectiveness of adjunctive group-based treatments for Chinese outpatients with BD. A single-blind trial in which 68 outpatients with BD were randomly assigned to either treatment as usual (TAU) or to an experimental group with 12 additional weekly sessions and 3 monthly booster sessions. Participants were assessed at baseline for mood condition, suicidal ideation, medication adherence, and quality of life (QoL), with follow-up assessments every 3 months over a 1-year period. The overall retention rate of this study was 89.7%. The results showed significant differences between groups for the variables evaluated, which included achieving euthymia, decrease of depression symptoms, and improvement of QoL. No improvements in medication adherence, reduction in manic symptoms, or suicidal ideation was observed. The results of this study support the transcultural validity and efficacy of group-based psychosocial intervention as anadjunct to TAU among Chinese outpatients with BD to promote improvements during the course of the illness including achieving euthymia, reducing depressive symptoms, and improving QoL.

Associations of diabetes severity and risk of depression: a population-based cohort study

OBJECTIVE

Previous literature investigating effects of diabetes complications on subsequent depression have been inconsistent. We aim to investigate associations of diabetes, complication severity, and depression.

DESIGN

This study used a nationwide database to establish an 11-year cohort comprised of people with new onset Type II diabetes mellitus (DM) aged 20 and above.

METHOD

Severity of DM was measured using the adapted Diabetes Complication Severity Index (aDCSI). Status of depression was determined by having one recorded depression diagnosis from the inpatient setting or three recorded depression diagnoses from the outpatient setting. The risk of depression was analyzed by multivariate Cox proportional models.

RESULTS

In 50,590 cases with new onset DM from years 2000 to 2011, the incidence of depression increased with severity and rates of progressions in diabetes complications regardless of demographic status, comorbidities, or medication compliance. Adjusted hazard ratios (aHR) of depression were 1.21, 1.25, 1.48 (p<0.001 for trend) in patients with a total aDCSI score of 1, 2, and > 3, respectively. Risks of depression were the highest in subgroup with the most serious progression (change of aDCSI score >2 per year) (aHR ranged between 11.6~26.0). Elevated risks of depression (aHR: 1.59~4.36) were also observed in the slower progression subgroups throughout the disease course.

CONCLUSIONS

Risks of depression were associated with multiple DM-related complications and rates of progression in severity.

GSTM3 variant is a novel genetic modifier in Brugada syndrome, a disease with risk of sudden cardiac death

BACKGROUND

Brugada syndrome (BrS) is a rare inherited disease causing sudden cardiac death (SCD). Copy number variants (CNVs) can contribute to disease susceptibility, but their role in Brugada syndrome (BrS) is unknown. We aimed to identify a CNV associated with BrS and elucidated its clinical implications.

METHODS

We enrolled 335 unrelated BrS patients from 2000 to 2018 in the Taiwanese population. Microarray and exome sequencing were used for discovery phase whereas Sanger sequencing was used for the validation phase. HEK cells and zebrafish were used to characterize the function of the CNV variant.

FINDINGS

A copy number deletion of GSTM3 (chr1:109737011-109737301, hg38) containing the eighth exon and the transcription stop codon was observed in 23.9% of BrS patients versus 0.8% of 15,829 controls in Taiwan Biobank (P < 0.001), and 0% in gnomAD. Co-segregation analysis showed that the co-segregation rate was 20%. Patch clamp experiments showed that in an oxidative stress environment, GSTM3 down-regulation leads to a significant decrease of cardiac sodium channel current amplitude. Ventricular arrhythmia incidence was significantly greater in gstm3 knockout zebrafish at baseline and after flecainide, but was reduced after quinidine, consistent with clinical observations. BrS patients carrying the GSTM3 deletion had higher rates of sudden cardiac arrest and syncope compared to those without (OR: 3.18 (1.77-5.74), P<0.001; OR: 1.76 (1.02-3.05), P = 0.04, respectively).

INTERPRETATION

This GSTM3 deletion is frequently observed in BrS patients and is associated with reduced I_Na, pointing to this as a novel potential genetic modifier/risk predictor for the development of the electrocardiographic and arrhythmic manifestations of BrS.

FUNDING

This work was supported by the Ministry of Science and Technology (107-2314-B-002-261-MY3 to J.M.J. Juang), and by grants HL47678, HL138103 and HL152201 from the National Institutes of Health to CA.

Clinical Outcomes of Complete Left Bundle Branch Block According to Strict or Conventional Definition Criteria in Patients with Normal Left Ventricular Function

BACKGROUND

Complete left bundle branch block (cLBBB) is associated with poor outcomes in patients with heart failure (HF) but appears to have minimal effects on cardiovascular (CV) mortality in relatively healthy adults. New criteria to define strict cLBBB have been proposed.

OBJECTIVES

The aim of this study was to stratify the potential risk of cLBBB according to conventional or strict criteria in patients with normal ejection fraction (EF).

METHODS

Patients with cLBBB from 2010 to 2013 who underwent baseline echocardiography within 1 year and had a left ventricular ejection fraction (LVEF) > 50% were enrolled. A control group of patients without intraventricular conduction abnormalities matched for age and sex was included. Primary outcomes including CV mortality, HF admission, EF reduction of 40%, and total mortality were compared.

RESULTS

A total of 137 patients with cLBBB were included, of whom 118 had strict cLBBB. The mean age was 72 ± 15 years and 56.2% were men. With a median follow-up of 4.3 years, normal LVEF patients with cLBBB but without a history of atrial fibrillation had a significantly higher risk of CV mortality (p < 0.001), EF reduction to 40% (p < 0.001), and admission for HF (p < 0.001). A similar risk of CV events was noted for the patients with conventional and strict cLBBB.

CONCLUSIONS

In patients with normal EF and without a history of atrial fibrillation, the presence of cLBBB led to a greater risk of CV mortality, HF admission and EF reduction to < 40%. Strict cLBBB carries a similar risk of CV events to conventional cLBBB.

Increases in repolarization heterogeneity predict left ventricular systolic dysfunction and response to cardiac resynchronization therapy in patients with left bundle branch block

INTRODUCTION

This study aimed to investigate the association between T-wave morphology and impaired left ventricular ejection fraction (LVEF) in patients with complete left bundle branch block (cLBBB), and the predictive value of T-wave morphology for response to cardiac resynchronization therapy (CRT).

METHODS AND RESULTS

We enrolled 189 patients with cLBBB on electrocardiogram performed between January 2007 and December 2011 who underwent standard echocardiography. Repolarization parameters, including the QRS-to-T angle (TCRT), T-wave morphology dispersion (TMD), T-wave loop area (PL), and T-wave residuum (TWR), were reconstructed from digital standard 12-lead electrocardiograms by T-wave morphology analysis. CRT response was defined as ≥15% reduction in left ventricular end-systolic volume at 12 months after CRT implantation. The clinical outcome endpoint was a composite of heart failure hospitalization, heart transplantation, or death during follow up (mean, 5.8 years). On logistic regression, a higher heart rate, longer QRS duration, increased TMD, and larger TWR were all independently associated with LVEF < 40%. Among 40 patients who underwent CRT, those with a larger TMD (P = .007), larger PL (P = .025), and more negative TCRT (P = .015) had better response to CRT. A large TMD (P = .018) and large PL (P = .003) were also independent predictors of the clinical outcome endpoint.

CONCLUSIONS

Increases in repolarization heterogeneity in patients with cLBBB are associated with impaired LVEF. A large TMD and large PL may be useful as additional predictors of response to CRT, improving patient selection for CRT.

Validation and Disease Risk Assessment of Previously Reported Genome-Wide Genetic Variants Associated With Brugada Syndrome: SADS-TW BrS Registry

BACKGROUND

Brugada syndrome (BrS) is an oligogenic arrhythmic disease with increased risk of sudden cardiac arrest. Several BrS or ECG traits-related single-nucleotide polymorphisms (SNPs) were identified through previous genome-wide association studies in white patients. We aimed to validate these SNPs in BrS patients in the Taiwanese population, assessing the cumulative effect of risk alleles and the BrS-polygenic risk score in predicting cardiac events.

METHODS

We genotyped 190 unrelated BrS patients using the TWB Array, and Taiwan Biobank was used as controls. SNPs not included in the array were imputed by IMPUTE2. Cox proportional hazards model was used to evaluate the associations between each particular SNP, the collective BrS-polygenic risk score, and clinical outcomes.

RESULTS

Of the 88 previously reported SNPs, 22 were validated in Taiwanese BrS patients (P<0.05). Of the 22 SNPs, 2 (rs10428132 and rs9388451) were linked with susceptibility to BrS, 10 were SNPs previously reaching genome-wide significance, and 10 were SNPs associated with ECG traits. For the 3 most commonly reported SNPs, disease risk increased consistently with the number of risk alleles (odds ratio, 3.54; P_trend=1.38×10^-9 for 5 risk alleles versus 1). Similar patterns were observed in both SCN5A mutation+ (odds ratio, 3.66; P_trend=0.049) and SCN5A mutation- (odds ratio, 3.75; P_trend=8.54×10^-9) subgroups. Furthermore, BrS patients without SCN5A mutations had more risk alleles than BrS patients with SCN5A mutations regardless of the range of polygenic risk scores. Three SNPs (rs4687718, rs7784776, and rs2968863) showed significant associations with the composite outcome (sudden cardiac arrest plus syncope, hazard ratio, 2.13, 1.48, and 0.41; P=0.02, 0.006, and 0.008, respectively).

CONCLUSIONS

Our findings suggested that some SNPs associated with BrS or ECG traits exist across multiple populations. The cumulative risk of the BrS-related SNPs is similar to that in white BrS patients, but it appears to correlate with the absence of SCN5A mutations.

Brief Cognitive-based Psychosocial Intervention and Case Management for Suicide Attempters Discharged from the Emergency Department in Taipei, Taiwan: A Randomized Controlled Study

OBJECTIVE

We examined the effectiveness of brief cognitive-based psychotherapy plus standard case management in the prevention of further suicide attempts, clinical severity, and treatment adherence in a randomized clinical trial compared with standard case management.

METHOD

Among five hundred and ninety-seven patients presenting with suicide attempts, 147 participants were included. They were randomized into two groups. After a 6-session intervention over four months, all participants were re-evaluated at the 6th and 12th months.

RESULTS

At a 6-month assessment, the intervention had approximately halved the odds of following suicide attempts and doubled the odds of outpatient visits in comparison with standard case management, although the differences did not attain statistical significance. At a 12-month assessment, the two groups did not differ significantly in any of the outcome variables. Generalized linear mixed models indicated that intervention did not significantly decrease the subsequent suicide risk and severity of clinical symptoms, but it did increase psychiatric outpatient treatment adherence. The subgroup analysis revealed that the intervention increased the outpatient clinic visits only for repetitive attempters, not for first-time attempters.

CONCLUSIONS

Further studies are needed to test whether more intensive psychotherapy sessions might be more effective in decreasing the probability of further attempt and the severity of symptoms.

P0545DPP-4 INHIBITOR ATTENUATED RENAL VASOCONSTRICTION FOLLOWING ISCHEMIA-REPERFUSION INJURY IN CIRRHOTIC RATS

Background and Aims

Cirrhotic patients may develop gastroesophageal varices to cope with portal hypertension. Annual risk of variceal bleeding among small and large varices is 5% and 15%, respectively. Bleeding from varices is a medical emergency and is associated with a high morbidity and mortality. In those who survive the initial bleeding event, the risks of further bleeding and other serious complications remain high, such as hypotension and ischemia-reperfusion injury. Ischemia-reperfusion injury is a leading cause of acute kidney injury. In patients with advanced liver cirrhosis, variceal bleeding associated hypotension and ischemia-reperfusion injury may activated endogenous vasoconstrictors, leading to severe renal vasoconstriction and subsequent renal failure (so called hepatorenal syndrome). There was not effective treatment yet.

Dipeptidyl peptidase-4 (DPP-4) inhibitors, a new class of oral hypoglycemic agents, have shown potential pleiotropic effects, such as anti-inflammatory and anti-oxidant properties. Previous studies reported that inhibition of DPP-4 could attenuate the development of ischemia-reperfusion injury in kidney. Cumulated evidences indicates that DPP-4 inhibitors could attenuate the endothelin-1 induced contraction and increase endothelial-dependent vasodilation related to activation of endothelial nitric oxide synthase and increased production of nitric oxide. In addition, DPP-4 inhibitors may suppress inflammation and fibrosis in the kidneys independently of glycemic control. The aim of this study is to delineate the effect of DPP-4 inhibitors in renal vascular reactivity of cirrhotic rats following ischemia-reperfusion injury.

Method

Male Sprague-Dawley rats weighing 240-270 g were used for experiments. Secondary biliary cirrhosis were created by common bile duct ligation (CBDL). Rats receiving sham surgery (SHAM) were used as the control group. Linagliptin (3 mg/kg/day) or distilled water (DW) was administered via oral gavage since the 1st day throughout the 28th day after surgery. On the 29th day, all rats were randomized to control group or ischemia-reperfusion injury. Bilateral renal pedicles of rats in the ischemia-reperfusion injury group were clamped for 45 minutes with microvascular clamps. Thereafter, the clamps were removed and reperfusion was allowed by visual control. After 60 minutes of reperfusion period, kidneys were perfused in situ via right renal artery for continuous monitoring of renal perfusion pressure using a non-recirculating system.

Results

There was no significant difference in mean arterial pressure, heart rate, and portal pressure between DW and DPP-4 inhibitor treated groups in both SHAM and CBDL rats. Ischemia-reperfusion injury enhanced renal vascular reactivity to endothelin-1 in both SHAM (p = 0.027) and CBDL (p = 0.016) rats, implying renal vasoconstriction. Compared with corresponding DW-treated rats, DPP-4 inhibitor treatment abrogated renal hyper-reactivity following ischemia-reperfusion injury in BDL rats (p = 0.038), but not in SHAM rats (p = 0.17).

Conclusion

We concluded that DPP-4 inhibitors may attenuate the development of renal vasoconstriction following ischemia-reperfusion injury in cirrhotic rats. The potentially mechanisms remained to be elucidated.

Sustained effects of faculty leadership development modules for clinical instructors of core competences education in Taiwan: a four-year explanatory case study

BACKGROUND

The Accreditation Council for Graduate Medical Education (ACGME) core competencies (CC) in general medicine-based primary care are essential for junior medical trainees. In this country, a regular faculty development (FD) program aimed at training faculty in instructing (teaching and assessing) these CC had operated. However, leadership was not emphasized. In a new intervention module, the roles and associated responsibilities of clinical instructors to conduct, design, and lead CC-based education were emphasis.

AIMS

This follow-up explanatory case study compares the effectiveness of intervention module with that of the previous regular module.

METHODS

The regular group (n = 28) comprised clinical instructors who participated in the FD module during the 2013-2014 year while the intervention group (n = 28) was composed of 2015-2016 participants. Prior to the formal (hands-on) training, participants in the intervention group were asked to study the online materials of the regular module. These participants then received a 30-h hands-on training in conducting, designing, and leading skills. Finally, they prepared a 10-h reflective end-of-module presentation of their real-world practices.

RESULTS

Following the training, a higher degree improvement in participants self-reported familiarity with CC education, self-confidence in their ability to deliver CC education and sustained involve CC education were noted among the intervention FD group, compared with the regular FD group. In the intervention group, senior academicians (associate and full professor) are more substantially involved in designing and leading CC-based courses than junior academicians (lecturers and assistant professors). Among non-teaching award winners of in the intervention FD group, the follow-up degree of sustained involvement in delivering, designing and leading CC-based courses was significantly higher than that of the regular group.

CONCLUSIONS

Our study demonstrated that leadership training in the intervention FD modules substantially motivated clinical instructors to become leaders in CC education.

NAFLD Aggravates Septic Shock Due to Inadequate Adrenal Response and 11β-HSDs Dysregulation in Rats

Background: Non-alcoholic fatty liver disease (NAFLD) is linked with metabolic syndrome. Previous studies showed that obesity may disrupt adrenal function and adversely affect its counter-regulations against shock. This study hence evaluated adrenal function abnormalities in NAFLD with shock. Methods: Sprague-Dawley rats were fed with regular chow-diet (control) or high fat diet (HFD, 60% energy derived from fat). Blood tests were performed at the end of the 4th, 6th and 8th week, respectively. Experiments were performed at the end of the 8th week. Results: HFD rats developed NAFLD. HFD rats had 27% and 51% increase in plasma corticosterone at the 6th and 8th week in usual status. However, HFD rats had 5 times more reduction of mean arterial pressure in response to lipopolysaccharide-induced sepsis as compared to control rats. The corticosterone increment ratio was also lower in HFD rats, even after ACTH administration. 11β-HSD system tended to generate more corticosterone in HFD rats under hemodynamic stable status without shock and the trend was lost in HFD rats with septic shock. Conclusion: Rats with NAFLD had profound septic shock due to inadequate corticosterone response. This is, at least partly, due to 11β-HSDs dysregulation in sepsis.

Dual Angiotensin Receptor and Neprilysin Inhibitor Ameliorates Portal Hypertension in Portal Hypertensive Rats

Background: Portal hypertension is characterized by exaggerated activation of the renin-angiotensin-aldosterone axis. Natriuretic peptide system plays a counter-regulatory role, which is modulated by neprilysin. LCZ696 (sacubitril/valsartan) is a dual angiotensin receptor and neprilysin inhibitor. This study evaluated the effect of LCZ696 on portal hypertensive rats. Methods: Portal hypertension was induced by partial portal vein ligation (PVL) in rats. LCZ696, valsartan (angiotensin receptor blocker), or normal saline (control) was administered in PVL rats for 10 days. Then, hemodynamic and biochemistry data were obtained. The hepatic histology and protein expressions were surveyed. On the parallel groups, the portal-systemic shunting degrees were determined. Results: LCZ696 and valsartan reduced mean arterial pressure and systemic vascular resistance. LCZ696, but not valsartan, reduced portal pressure in portal hypertensive rats (control vs. valsartan vs. LCZ696: 15.4 ± 1.6 vs. 14.0 ± 2.3 vs. 12.0 ± 2.0 mmHg, control vs. LCZ696: P < 0.05). LCZ696 and valsartan improved liver biochemistry data and reduced intrahepatic Cluster of Differentiation 68 (CD68)-stained macrophages infiltration. Hepatic endothelin-1 (ET-1) protein expression was downregulated by LCZ696. The portal-systemic shunting was not affected by LCZ696 and valsartan. Conclusion: LCZ696 and valsartan reduced mean arterial pressure through peripheral vasodilation. Furthermore, LCZ696 significantly reduced portal pressure in PVL rats via hepatic ET-1 downregulation.

A high-dose rapamycin treatment alleviates hepatopulmonary syndrome in cirrhotic rats

BACKGROUND

Rapamycin is a type of immunosuppressive agent that acts through inhibition of mammalian target of rapamycin (mTOR). Hepatopulmonary syndrome (HPS) is a lethal complication in cirrhotic patients. It is characterized by hypoxia and increased intrapulmonary shunts, in which pulmonary inflammation and angiogenesis play important roles. The current study aimed to evaluate the effect of rapamycin on HPS using the experimental model of common bile duct ligation (CBDL)-induced cirrhosis in rats.

METHODS

The rats received low-dose (0.5 mg/kg), high-dose (2 mg/kg) rapamycin, or vehicle from the 15th to the 28th day post CBDL. Then the mortality rate, hemodynamics, biochemistry parameters, arterial blood gas and plasma levels of vascular endothelial growth factor (VEGF) and tumor necrosis factor (TNF)-α were evaluated on the 28th day post CBDL. Pulmonary histopathological stains were performed, and protein expression was examined. In parallel groups, the intrapulmonary shunts of CBDL rats were measured.

RESULTS

Compared with the control, a high-dose rapamycin treatment decreased portal pressure and improved hypoxia in CBDL rats. It also reduced the plasma level of VEGF and TNF-α and decreased intrapulmonary shunts. Meanwhile, it ameliorated pulmonary inflammation and angiogenesis and downregulated the protein expression of mTOR, P70S6K, nuclear factor kappa B (NFκB), VEGF, and VEGF receptor 2. In contrast, low-dose rapamycin did not attenuate intrapulmonary shunts despite ameliorating portal hypertension.

CONCLUSION

High-dose rapamycin ameliorates HPS in cirrhotic rats as evidenced by the alleviated hypoxia and decreased intrapulmonary shunts. Downregulation of the mTOR/P70S6K, NFκB, and VEGF signaling pathways might play a key role.

Reducing Interface Traps with High Density Hydrogen Treatment to Increase Passivated Emitter Rear Contact Cell Efficiency

In this work, a high-density hydrogen (HDH) treatment is proposed to reduce interface traps and enhance the efficiency of the passivated emitter rear contact (PERC) device. The hydrogen gas is compressed at pressure (~ 70 atm) and relatively low temperature (~ 200 °C) to reduce interface traps without changing any other part of the device's original fabrication process. Fourier-transform infrared spectroscopy (FTIR) confirmed the enhancement of Si-H bonding and secondary-ion mass spectrometry (SIMS) confirmed the SiN/Si interface traps after the HDH treatment. In addition, electrical measurements of conductance-voltage are measured and extracted to verify the interface trap density (Dit). Moreover, short circuit current density (Jsc), series resistance (Rs), and fill factor (F.F.) are analyzed with a simulated light source of 1 kW M^-2 global AM1.5 spectrum to confirm the increase in cell efficiency. External quantum efficiency (EQE) is also measured to confirm the enhancement in conversion efficiency between different wavelengths. Finally, a model is proposed to explain the experimental result before and after the treatment.

Investigation of the Capacitance-Voltage Electrical Characteristics of Thin-Film Transistors Caused by Hydrogen Diffusion under Negative Bias Stress in a Moist Environment

In this study, the impact of moisture on the electrical characteristics of an amorphous In-Ga-Zn-O thin-film transistor (a-IGZO TFT) was investigated. In commercial applications of such TFTs, high stability and quality performance in humid environments are essential. During TFT operation under ambient moisture, the electrolysis of water molecules occurs via the tip electric field effect. Hydrogen diffuses from the etch-stop layer or back-channel into the main channel under a negative electric field. The hydrogen atoms act as shallow donors (which causes the carrier concentration in the channel to rise), causing the threshold voltage (V_TH) to shift in the negative direction. Hydrogen diffusion from the overlap of the source/drain and gate electrodes to the channel center caused by the tip electric field induces a significant barrier lowering and V_TH shifts in a short-channel device. However, under negative bias stress (NBS) in ambient moisture, the negative V_TH shift is more obvious in short- than in long-channel devices, indicating suppressed hydrogen diffusion in long-channel devices. This is attributed to the electrolysis of water by the tip electric field at the source, drain, and gate electrodes, which causes hydrogen to diffuse to the center of the channel. Here, a novel physical model of the capacitance-voltage (C-V) electrical property changes under ambient moisture is proposed, based on the early appearance of abnormalities in the C-V measurements. The electrolysis of water caused by the tip electric field and electrical abnormalities caused by hydrogen diffusion into the a-IGZO active layer are explained by this model. A secondary-ion mass spectrometry analysis shows that hydrogen content in the channel generally increases under NBS in ambient moisture. The degradation behavior due to moisture in a-IGZO is clarified. Thus, inhibiting the tip electric field may benefit future flexible-display and gas-sensing applications.

P1604Validating previously reported Brugada syndrome-associated common variants identified in caucasian population in the Han Chinese BrS cohort in Taiwan: SADS-BrS registry

Background

Brugada syndrome (BrS) is a sudden arrhythmic death. The prevalence of BrS is higher in the Southeast Asian populations than that in Caucasian patients. A previous genome-wide association study (GWAS) has reported 13 SNPs significantly associated with BrS. However, no study was performed to validate whether these SNPs are enriched in BrS patients in Han Chinese (HC).

Purpose

Evaluating the common variants previously reported in Caucasian BrS patients could be generalized to HC BrS patients in Taiwan

Methods

We genotyped 200 unrelated BrS patients using Affymetrix TWB Array (N=653,291 SNPs, a customized array for HC in Taiwan). The controls are obtained from the Taiwan Biobank (N ≈ 16,000) using the same array. An imputation workflow was shown in Figure 1. To confirm the accuracy of the imputed genotype of each variant, Sanger sequencing was performed in 10% of randomly selected cases.

Results

Among the 3 most important common variants (rs11708996 in SCN5A, rs10428132 in SCN10A and rs9388451 in HEY2/NCOA7) reported in the previous GWAS mainly conducted in Caucasian BrS patients, 2 of them (rs10428132 and rs9388451) were successfully replicated in the HC population in Taiwan (P<0.01). We also found that the differences of minor allele frequency (dMAF: the MAF of cases minus the MAF of controls) of the two variants were relatively smaller between the BrS cases and healthy controls in HC population compared with that in Caucasian populations (dMAF, rs9388451: 0.15 (Caucasian) vs −0.07 (HC); rs10428132: 0.28 (Caucasian) vs 0.11 (HC)). For the remaining 10 common variants reaching genome-wide significance (P=5×10–8) in Caucasian BrS patients, 9 of them were also significantly enriched in the HC BrS patients after the Bonferroni correction (P<0.05/12=0.0042). We next analyzed the variants identified in the previous GWAS on ECG traits (PR interval, QRS duration, QTc interval, and heart rate) in the Caucasian population. Among the reported 75 variants associated with ECG traits, 5 common variants (rs6798015 (PR), rs1760876 (QRS), rs6795970 (PR/QRS), rs2074238 (QTc) and rs314370 (heart rate)) were significant after Bonferroni correction (P<0.05/75=0.00066).

Figure 1

Conclusions

The preliminary results indicated that 85% of common variants of SCN10A and HEY2/NCOA7 previously reported in Caucasian BrS patients are replicated in BrS patients in the HC population but not the common variant of SCN5A (rs11708996). Furthermore, the common variants of SCN10A and HEY2/NCOA7 related to cardiac depolarization or repolarization may also contribute to the development of BrS.

Acknowledgement/Funding

NTUH 106-S3469, NTUH106-S3458 and NTUH 106-018

Nutrition Risk Assessment Using the Modified NUTRIC Score in Cirrhotic Patients with Acute Gastroesophageal Variceal Bleeding: Prevalence of High Nutrition Risk and its Independent Prognostic Value

Malnutrition is associated with adverse outcomes in patients with liver cirrhosis. Relevant data about nutrition risk in critically ill cirrhotic patients are lacking. The modified Nutrition Risk in Critically Ill (mNUTRIC) score is a novel nutrition risk assessment tool specific for intensive care unit (ICU) patients. This retrospective study was conducted to evaluate the prevalence and prognostic significance of nutrition risk in cirrhotic patients with acute gastroesophageal variceal bleeding (GEVB) using mNUTRIC scores computed on admission to the intensive care unit. The major outcome was 6-week mortality. One-hundred-and-thirty-one admissions in 120 patients were analyzed. Thirty-eight percent of cirrhotic patients with acute GEVB were categorized as being at high nutrition risk (a mNUTRIC score of ≥5). There was a significantly progressive increase in mortality associated with the mNUTRIC score (χ2 for trend, p < 0.001). By using the area under a receiver operating characteristic (ROC) curve, the mNUTRIC demonstrated good discriminative power to predict 6-week mortality (AUROC 0.859). In multivariate analysis, the mNUTRIC score was an independent factor associated with 6-week mortality. In conclusion, the mNUTRIC score can serve as a tool to assess nutrition risk in cirrhotic patients with acute GEVB.

Glucobrassicin Metabolites Ameliorate the Development of Portal Hypertension and Cirrhosis in Bile Duct-Ligated Rats

Patients suffering from liver cirrhosis are often complicated with the formation of portosystemic collateral vessels, which is associated with the progression of a splanchnic hyperdynamic circulatory state. Alleviating pathological angiogenesis has thus been proposed to be a feasible treatment strategy. Indole-3-carbinol (C9H9NO, I3C) and 3,3'-diindolymethane (DIM), formed by the breakdown of glucosinolate glucobrassicin, are prevalent in cruciferous vegetables and have anti-angiogenesis properties. We aimed to evaluate their influences on portal hypertension, the severity of mesenteric angiogenesis, and portosystemic collaterals in cirrhosis. Sprague-Dawley rats with common bile duct ligation (CBDL)-induced liver cirrhosis or sham operation (surgical control) were randomly allocated to receive I3C (20 mg/kg/3 day), DIM (5 mg/kg/day) or vehicle for 28 days. The systemic and portal hemodynamics, severity of portosystemic shunting, mesenteric angiogenesis, and mesenteric proangiogenic factors protein expressions were evaluated. Compared to vehicle, both DIM and I3C significantly reduced portal pressure, ameliorated liver fibrosis, and down-regulated mesenteric protein expressions of vascular endothelial growth factor and phosphorylated Akt. DIM significantly down-regulated pErk, and I3C down-regulated NFκB, pIκBα protein expressions, and reduced portosystemic shunting degree. The cruciferous vegetable byproducts I3C and DIM not only exerted a portal hypotensive effect but also ameliorated abnormal angiogenesis and portosystemic collaterals in cirrhotic rats.

Event-Related Desynchronization/Synchronization in Spinocerebellar Ataxia Type 3

Introduction: Spinocerebellar ataxia type 3 (SCA3) is an autosomal dominant, cerebellar degeneration predominant disease caused by excessive CAG repeats. We examined event-related dysynchronization/synchronization (ERD/ERS) in patients with SCA3.

Methods: We assessed ERD/ERS of self-paced voluntary hand movements in 15 patients with genetically proven SCA3 in comparison with healthy controls.

Results: In ERS, a significant interaction effect between group, frequency, and period (F = 1.591; p = 0.005; ρI = 0.86) was observed. The post-hoc two-tailed independent t-test showed significant differences in high beta and low beta ERS. By contrast, in ERD, no apparent differences were observed in the pattern of patients with SCA3 in comparison with healthy controls (F = 1.01; p = 0.442).

Conclusion: The study revealed a decreased ERS in patients with SCA3, especially at the frequency of 20–30 Hz. This study elucidates the significant role of cerebellum in motor control.