Abnormal Threshold Research Articles

Abnormal threshold voltage shift by the effect of H2O during negative bias stress in amorphous InGaZnO thin film transistors

We observed abnormal threshold voltage (VT) shift in amorphous InGaZnO (a-IGZO) thin-film transistors under negative gate bias stress (NBS) after soaking them in H2O (pH 8). Before NBS, we soaked a-IGZO TFTs in H2O. During application of NBS, VT decreased by −0.43 V, then increased to nearly the initial value. We hypothesize that the electrical field that was applied during NBS caused some dissociation of H2O to hydrogen ions (H+) and hydroxide ions (OH−); the effects between H+ and OH− are responsible for the changes of ΔVT. The initial decrease was a result of trapping of H+ at the front channel; the subsequent increase was caused by neutralization of the H+ and the OH−; the a-IGZO was very thin, so the front channel and the back channel could affect each other; therefore, mitigation of energy band bending was possible. Recovery after NBS also occurred in two-phases: VT first increased then decreased to its initial value. During the recovery process, accumulation of an OH− layer generated electric field that attracted H+ so that the two species recombined. Increase in ΔVT occurred due to desorption of H+ from the front-channel interface, and decrease in ΔVT occurred by recombination.

Thresholds of Abnormality Perception in Facial Esthetics among Laypersons and Dental Professionals: Frontal Esthetics.

Aim To find thresholds at which laypersons and dental professionals perceive abnormalities in two facial frontal esthetics variables: facial symmetry and vertical harmony. Materials and Methods A baseline frontal image of a young male face with optimum facial proportions was generated from a real image using a photo editing software. Different facial asymmetry images were then generated from this image by manipulating the chin point position at 2 mm increment to the left side. Vertical harmony was perceived through manipulating lower anterior facial height (LAFH) at a ratio of 2% of increased and decreased heights. A total of 120 raters divided equally into four groups of laypersons, general dental practitioners (GDPs), orthodontists, and oral and maxillofacial surgeons (OMFSs) rated these images using an analog scale of 100 mm long. Using ANOVA and Tukey post hoc tests at P < 0.05, the image that showed the first statistical difference compared to the baseline was considered as a threshold of abnormality. Results The image of 4 mm asymmetry was defined by the laypersons and GDPs as the threshold of abnormality, while the orthodontists and OMFSs realized that at 2 mm. Laypersons and GDPs defined a threshold of 46% as an abnormal decrease in the LAFH and the other 2 groups at 48%. All dental professionals groups rated the image of 54% as an abnormal increase in the LAFH while laypersons perceived that at 56%. Conclusion These thresholds regarding frontal esthetics may contribute to the process of establishing proper orthodontic treatment planning that suits the highest facial esthetic standards.

Thresholds of Abnormality Perception in Facial Esthetics among Laypersons and Dental Professionals: Profile Esthetics.

Aim To find thresholds at which laypersons and dental professionals from Jordanian population perceive abnormalities in sagittal positioning of upper and lower jaws as a major determinant to facial profile esthetics. Materials and Methods Using photo editing software, a baseline profile image of a young male was manipulated on a 2 mm incremental basis to move each of the upper and lower jaws backward and forward relative to true vertical line (TVL) at which four variables of maxillary and mandibular retrusion and protrusion were researched. A total of 120 participants divided equally into four groups of laypersons, general dental practitioners (GDPs), orthodontists, and oral and maxillofacial surgeons (OMFSs) rated the images using an analog scale of 100 mm long. The image that showed the first statistical difference compared to the baseline was considered as a threshold of abnormality. Results Laypersons, GDPs, and OMFSs perceived the abnormality in the maxillary retrusion at −5 mm to TVL, while orthodontists defined that at −3 mm. All dental professionals perceived the abnormality in the maxillary protrusion at +1 mm to TVL while the layperson group at +3 mm. A threshold of −7 mm mandibular retrusion to TVL was abnormally perceived by all groups. All dental professionals realized the abnormality in the mandibular protrusion at 0 mm to TVL while the laypersons at +2 mm. Conclusion These thresholds regarding profile esthetics may contribute to the process of establishing proper orthodontic treatment planning that suits the highest facial esthetic standards.

Lipopolysaccharide-binding protein is a distinctive biomarker of abnormal pain threshold in the general Japanese population

IntroductionSmall fiber neuropathy (SFN) is an early manifestation in diabetic polyneuropathy (DPN); however, the mechanisms are not fully understood. In diabetes, SFN is presumed to be common in individuals with...

Examination Techniques of the First Cranial Nerve: What Neurosurgical Residents Should Know.

Olfactory or smell dysfunction is often overlooked by clinicians despite being prevalent in the population. To date in Malaysia, there is no standard and reliable test to examine the function of olfaction. Tests used at developed countries such as the Sniffin’ Sticks Test (SST), the Connecticut Chemosensory Clinical Research Center (CCCRC) test, the University of Pennsylvania Smell Identification Test (UPSIT) and the Brief Smell Identification Test (B-SIT) are not readily available in this region and may be costly to procure. The first cranial nerve can be tested using commonly available materials to assess: i) the function of odour detection; ii) the odour discrimination; and iii) the odour identification. An abnormal odour detection threshold test generally indicates a peripheral olfactory problem while the odour discrimination and identification test attribute the problem to the cerebral cortex. An olfactory complaint should not be taken lightly and a proper olfactory function examination is important: i) to determine the legitimacy of a patient’s complaint; ii) to monitor the progress of patient’s olfactory function; iii) to establish insurance payout for disability; and iv) to characterise the specific nature of the problem.A video has been produced to demonstrate the examination techniques explained in this article.

Neurodegenerative Diseases and the Auditory-Vestibular System

Neurodegenerative Diseases and the Auditory-Vestibular System

Traffic Flow Anomaly Detection Based on Robust Ridge Regression with Particle Swarm Optimization Algorithm

Traffic flow anomaly detection is helpful to improve the efficiency and reliability of detecting fault behavior and the overall effectiveness of the traffic operation. The data detected by the traffic flow sensor contains a lot of noise due to equipment failure, environmental interference, and other factors. In the case of large traffic flow data noises, a traffic flow anomaly detection method based on robust ridge regression with particle swarm optimization (PSO) algorithm is proposed. Feature sets containing historical characteristics with a strong linear correlation and statistical characteristics using the optimal sliding window are constructed. Then by providing the feature sets inputs to the PSO-Huber-Ridge model and the model outputs the traffic flow. The Huber loss function is recommended to reduce noise interference in the traffic flow. The L2 regular term of the ridge regression is employed to reduce the degree of overfitting of the model training. A fitness function is constructed, which can balance the relative size between the k-fold cross-validation root mean square error and the k-fold cross-validation average absolute error with the control parameter η to improve the optimization efficiency of the optimization algorithm and the generalization ability of the proposed model. The hyperparameters of the robust ridge regression forecast model are optimized by the PSO algorithm to obtain the optimal hyperparameters. The traffic flow data set is used to train and validate the proposed model. Compared with other optimization methods, the proposed model has the lowest RMSE, MAE, and MAPE. Finally, the traffic flow that forecasted by the proposed model is used to perform anomaly detection. The abnormality of the error between the forecasted value and the actual value is detected by the abnormal traffic flow threshold based on the sliding window. The experimental results verify the validity of the proposed anomaly detection model.

Hydrogen Impacts of PEALD InGaZnO TFTs Using SiOx Gate Insulators Deposited by PECVD and PEALD

Amorphous indium gallium zinc oxide (IGZO) deposited by plasma-enhanced atomic layer deposition (PEALD) thin-film transistors (TFTs) was fabricated using SiO2 gate insulators synthesized via plasma-enhanced chemical vapor deposition (PECVD, device A) or PEALD (device B). The electrical performance of B devices was higher than that of device A. The mobilities of A and B devices were 19.39 and 21.11 cm2/Vs, and the subthreshold slopes were 0.25 and 0.22 V /decade, respectively. In addition, the device reliability of A devices shows an abnormal threshold voltage ( ${V}_{\text {th}}$ ) shift of –1.25 V under positive bias temperature stress (PBTS), caused by hydrogen diffusion from the gate insulator to the channel region near the source/drain electrode. However, B devices had a normal ${V}_{\text {th}}$ shift of +2.87 V. X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FT-IR) results showed that PECVD SiO2 has a large amount of hydrogen bonding, such as Si-OH, compared to PEALD SiO2. Rutherford backscattering spectroscopy (RBS) and elastic recoil detection (ERD) measurement results confirmed that the hydrogen content of PECVD SiO2 was 2.24%, whereas that of PEALD SiO2 was lower at 1.45%.

Perfusion Parameter Thresholds That Discriminate Ischemic Core Vary with Time from Onset in Acute Ischemic Stroke.

When mapping the ischemic core and penumbra in patients with acute ischemic stroke using perfusion imaging, the core is currently delineated by applying the same threshold value for relative CBF at all time points from onset to imaging. We investigated whether the degree of perfusion abnormality and optimal perfusion parameter thresholds for defining ischemic core vary with time from onset to imaging. In a prospectively maintained registry, consecutive patients were analyzed who had ICA or M1 occlusion, baseline perfusion and diffusion MR imaging, treatment with IV tPA and/or endovascular thrombectomy, and a witnessed, well-documented time of onset. Ten superficial and deep MCA ROIs were analyzed in ADC and perfusion-weighted images. Among the 66 patients meeting entry criteria, onset-to-imaging time was 162 minutes (range, 94-326 minutes). Of the 660 ROIs analyzed, 164 (24.8%) showed severely or moderately reduced ADC (ADC ≤ 620, ischemic core), and 496 (75.2%), mildly reduced or normal ADC (ADC > 620). In ischemic core ADC regions, longer onset-to-imaging times were associated with more highly abnormal perfusion parameters-relative CBF: Spearman correlation, r = -0.22, P = .005; relative CBV: r = -0.41, P < .001; MTT: - r = -0.29, P < .001; and time-to-maximum: r = 0.35, P < .001. As onset-to-imaging times increased, the best cutoff values for relative CBF and relative CBV to discriminate core from noncore tissue became progressively lower and overall accuracy of the core tissue definition increased. Perfusion abnormalities in ischemic core regions become progressively more abnormal with longer intervals from onset to imaging. Perfusion parameter value thresholds that best delineate ischemic core are more severely abnormal and have higher accuracy with longer onset-to-imaging times.

Dual staining for p16/Ki-67 to detect high-grade cervical lesions: Results from the Screening Triage Ascertaining Intraepithelial Neoplasia by Immunostain Testing study.

We compared clinical performance of p16/Ki-67 dual-stained cytology and human papillomavirus (HPV) genotyping, via different algorithms-alone, or in combination with cytology-to identify cervical intraepithelial neoplasia grade 2 or worse (CIN2+) and grade 3 or worse (CIN3+) in women referred to as colposcopy. We included 492 cervical specimens (134 normal, 130 CIN1, 99 CIN2, 121 CIN3, 8 cancers) randomly selected from 1158 specimens with valid conventional cytology, HPV (cobas 4800 HPV test) and biopsy results. Dual-stained cytology was retrospectively performed (CINtec PLUS assay) on PreservCyt material; slides were read by a cytologist and confirmed by two pathologists, blinded to cytology, biopsy and genotyping results. Sensitivity and specificity (95% confidence intervals in parentheses) of dual-stained cytology to detect CIN2+ and CIN3+ were compared to other screening tests available for the same women. Positivity rate for dual-stained cytology increased with histological severity: 30.6% in normal, 41.5% in CIN1, 72.7% in CIN2, 86.8% in CIN3 and 87.5% in cancer. Dual-stained cytology alone had lower sensitivity than HPV testing for CIN2+ [80.7% (75.0-85.6) vs 89.9% (85.3-93.5)] and CIN3+ [86.8% (79.7-92.1) vs 92.3% (86.2-96.2)]. However, corresponding specificity values were higher [64.0% (57.9-69.8) vs 56.1% (49.8-62.1) for CIN2+; 54.0% (48.7-59.2) vs 44.4% (39.2-49.6) for CIN3+]. Combining dual-stained cytology with an ASC-US abnormality threshold decreased specificity to 31.4% (25.9-37.4) for CIN2+ and 24.2% (19.9-29.0) for CIN3+. The corresponding values considering low squamous intraepithelial lesion threshold values were 42.8% (36.8-49.0) and 35.0% (30.1-40.1). Dual-stained cytology and HPV testing exhibited similar performance, although the former improved the specificity by 7.9% and 9.6% for CIN2+ and CIN3+, respectively.

Visual Perception of Heading in the Syndrome of Oculopalatal Tremor.

Perception of our linear motion, heading, relies on convergence from multiple sensory systems utilizing visual and vestibular signals. Multisensory convergence takes place in the visuo-vestibular areas of the cerebral cortex and posterior cerebellar vermis. Latter closely connected with the inferior olive may malfunction in disorders of olivo-cerebellar hypersynchrony, such as the syndrome of oculopalatal tremor (OPT). We had recently shown an impairment in vestibular heading perception in the subjects with OPT. Here we asked whether the hypersynchrony in the inferior-olive cerebellar circuit also affects the visual perception of heading, and the impairment is coupled with the deficits in vestibular heading perception. Three subjects with OPT and 11 healthy controls performed a two-alternative forced-choice task in two separate experiments; one when they were moved en bloc in a straight-ahead forward direction or at multiple heading angles to the right or the left; and second when under virtual reality goggle they experienced the movement of star cloud leading to the percept of heading straight, left or to the right at the heading angles similar to those utilized in the vestibular task. The resultant psychometric function curves, derived from the two-alternative-forced-choice task, revealed abnormal threshold to perceive heading direction, abnormal sensitivity to the change in heading direction compared to straight ahead, and a bias towards one side. Although the impairment was present in both visual and vestibular heading perception, the deficits were not coupled.

The Monitoring of Donor-derived Cell-free DNA in Kidney Transplantation.

Cell-free DNA (cfDNA) exists in plasma and can be measured by several techniques. It is now possible to differentiate donor-derived cfDNA (ddcfDNA) from recipient cfDNA in the plasma or urine of solid organ transplant recipients in the absence of donor and recipient genotyping. The assessment of ddcfDNA is being increasingly studied as a noninvasive means of identifying acute rejection (AR) in solid organ transplants, including subclinical AR. We herein review the literature on the correlation of ddcfDNA with AR in kidney transplantation. There have been at least 15 observational studies that have assessed ddcfDNA in urine or plasma using various methodologies with various thresholds for abnormality. Overall, elevated ddcfDNA indicates allograft injury as may occur with AR, infection, or acute tubular injury but may also be found in clinically stable patients with normal histology. Sensitivity is greater for antibody-mediated AR than for cell-mediated AR, and normal levels do not preclude significant cell-mediated rejection. Measurement of ddcfDNA is not a replacement for biopsy that remains the gold standard for diagnosing AR. Serial monitoring of stable patients may allow earlier detection of subclinical AR, but the efficacy of this approach remains to be established. Normal levels should not preclude planned protocol biopsies. There may be roles for following ddcfDNA levels to assess the adequacy of treatment of AR and to guide the intensity of immunosuppression in the individual patient. Randomized controlled trials are necessary to validate the benefit and cost-effectiveness for these various uses. No firm recommendations can be made at this time.

Bayesian analysis on interactions of exotic nuclear systems

Even though the Bayesian method has been proved to be powerful in the field of nuclear physics, it has not yet been implemented to study the properties of the reaction systems with exotic nuclei, for instance, the gross feature of the phenomenological interaction potential. So far, the optical model potential was typically evaluated by the traditional frequentist approach. However, contradictive conclusions were drawn, especially on the near-threshold behavior of the imaginary potential: threshold anomaly and abnormal threshold anomaly were derived for 6Li+209Bi and 6He+208Pb even with the same elastic scattering data. In this study, we first applied the Bayesian framework to analyze the elastic scattering data of 6Li+209Bi. It was found that the results of Bayesian statistics strongly depend on the imposed prior distributions. Therefore, the Bayesian method has to be used with extreme caution, since the improper prior knowledge could lead to completely wrong conclusions. Since the elastic scattering data is not informative enough to constrain the prior and posterior distributions, our analysis further indicates that the results from the non-constraint frequentist approach or the flat prior distribution with a reasonable physical-boundary can be employed as convincing prior knowledge of the Bayesian framework. Based on this result, we further applied the Bayesian approach to the transfer reaction 208Pb(7Li,6He)209Bi, to investigate the optical potentials of the neutron halo system 6He+209Bi in the outgoing channel. With the proper prior distributions, the Bayesian analysis on both the 6Li+209Bi and 6He+208Pb confirm the presence of the abnormal threshold anomaly. Therefore the applicability of the dispersion relation remains in doubt.

EIT PACMAN Study preliminary results: OncoSignal pathway analysis identifies actionable cancer targets.

e15606 Background: Precision medicine refers to tailoring of treatment to each individual patient, although identifying tumor driving signaling pathways (SP) that are functionally active is still a challenge. OncoSignal pathway tests quantitatively measure activity of SP such as estrogen receptor (ER), androgen receptor (AR), PI3K, MAPK, Hedgehog (HH), TGF-β, Notch on fresh frozen and formalin-fixed paraffin-embedded (FFPE) tissue samples. OncoSignal pathway analysis aimed at assessing clinically actionable SP and retrospectively predicting targeted drug response on a series of patients’ (pts) samples from the MOSCATO trial run at Gustave Roussy. Methods: OncoSignal pathway analysis (ER, AR, PI3K, MAPK, HH, Notch, TGF-β) was performed blinded by Molecular Pathway Dx (Philips, Eindhoven) on metastatic tumor tissue samples from breast cancer (BC), prostate (PC), and high grade serous ovarian cancers (OC). Using Affymetrix expression array data from public GEO datasets, SP activity was analyzed in healthy prostate, breast, and ovarian tissue to define abnormal SP activity thresholds for tumor tissue pathway analysis. For each individual sample, SP alterations were considered tumor driving SP if sample SP activity exceeded the 95th percentile of SP activity within healthy tissue. Results by OncoSignal were also combined with clinical characteristics and molecular alterations identified in the MOSCATO trial. Results: Identified tumor driving SP were ER, AR, MAPK-AP1, HH, PI3K pathway in BC (n = 5), AR in PC (n = 30); AP1, Notch, TGFβ in OC (n = 17). OncoSignal identified clinically actionable tumor driving pathways in all BC samples (median tumor cellularity [MTC]: 40%, range 15-80%); 30/31 PC samples (MTC: 62%, range 25-90%), 16/17 OC samples (MTC 62%, range 15-80%). Actionable mutations were previously identified in 4/5 BC; 13/31 PC; 6/17 OC. Seven pts with BC and PC were treated with targeted therapy. OncoSignal pathway analysis correctly predicted response/resistance in 4 of these pts (57%). Conclusions: OncoSignal pathway analysis correctly identified SP activity alterations and predicted targeted drug response in this series of patients. OncoSignal will be further validated prospectively in precision medicine studies at Gustave Roussy in which patients are stratified for targeted treatment by mutation analysis.

Associations of Small Fiber Neuropathy with Geriatric Nutritional Risk Index and Arterial Stiffness in Hemodialysis.

Background Peripheral neuropathy is a common neurological complication in uremic patients, and quantitative sensory testing (QST) is effective for diagnosis of small fiber neuropathy. Malnutrition and arterial stiffness are prevalent in patients undergoing hemodialysis (HD). The associations of small fiber neuropathy with nutritional status and arterial stiffness remain uncertain in maintenance HD patients. Methods A total of 152 HD patients were included. Geriatric nutritional risk index (GNRI), an indicator of nutritional status, was calculated by serum albumin and actual and ideal body weight. Arterial stiffness was defined as brachial-ankle pulse wave velocity (baPWV) > 1400 cm/s. Small fiber neuropathy was assessed by an abnormal QST threshold of cold and warm sensation in patients' hands or feet. Multivariate forward logistic regression analysis was performed to examine the associations among abnormal QST threshold, GNRI, and arterial stiffness. Results baPWV and prevalence of abnormal QST threshold were significantly higher in diabetic patients. Multivariate logistic analyses revealed that older age (OR, 1.081; 95% CI, 1.026–1.139, p = 0.003) and male gender (OR, 4.450; 95% CI, 1.250–15.836, p = 0.021) were associated with abnormal warm threshold of hands. Furthermore, diabetes (OR, 3.966; 95% CI, 1.351–11.819, p = 0.012) and lower GNRI (per 1 unit increase, OR, 0.935, 95% CI, 0.887–0.985, p = 0.012) were associated with abnormal cold threshold of feet. Arterial stiffness (OR, 5.479, 95% CI, 1.132–22.870, p = 0.020) and higher calcium-phosphorus product (OR, 1.071, 95% CI, 1.013–1.132, p = 0.015) were associated with abnormal warm threshold of feet. Conclusions Lower GNRI and arterial stiffness were significantly associated with small fiber neuropathy in patients undergoing HD. Malnutrition risk and vascular factors might play important roles in small fiber neuropathy among patients undergoing HD.

Evidence for normal intracortical inhibitory recruitment properties in cervical dystonia

ObjectiveDystonia is associated with reduced intracortical inhibition as measured by the cortical silent period (cSP); however, this may be due to abnormal cSP threshold or input-output properties. This study evaluated cSP recruitment properties in people with cervical dystonia (CD). MethodsBilateral electromyographic recordings were collected in the upper trapezius muscle in response to transcranial magnetic stimulation of the left and right primary motor cortex in a group with CD (n = 19) and controls (n = 21). cSP threshold, cSP input-output properties at stimulation intensities from 1 to 1.4x the cSP threshold, ipsilateral silent period duration (iSP) and timing and magnitude of the contralateral and ipsilateral motor evoked potential (MEP) were assessed. ResultsThe cSP threshold, input-output properties, and contralateral MEP magnitude were not significantly different between groups (all p > 0.07). Hemispheric symmetry was present in the control group while the CD group had reduced iSP (p < 0.01) and a trend for reduced ipsilateral MEP response (p = 0.053) in the left hemisphere. ConclusionsRecruitment properties of intracortical inhibition are similar between control and CD groups. Transcallosal inhibition is asymmetric between hemispheres in people with CD. SignificanceEvidence of normal intracortical inhibition recruitment properties challenge the commonly held view that cortical inhibition is reduced in dystonia.

Corrigendum: Normal High HbA1c a Risk Factor for Abnormal Pain Threshold in the Japanese Population.

[This corrects the article DOI: 10.3389/fendo.2019.00651.].

The use of quantitative sensory testing in cancer pain assessment: A systematic review.

To summarize the literature on the use of quantitative sensory testing (QST) in the assessment of pain in people with cancer and to describe which QST parameters consistently demonstrate abnormal sensory processing in patients with cancer pain. Medline, EMBASE, AMED, CINAHL, SCOPUS and CENTRAL were searched for observational or experimental studies using QST in patients with a cancer diagnosis and reporting pain. Search strategies were based on the terms "quantitative sensory testing", "cancer", "pain", "cancer pain" and "assessment". Databases were searched from inception to January 2019. Data were extracted and synthesized narratively, structured around the different QST modalities and sub-grouped by cancer pain aetiology (tumour- or treatment-related pain). Searches identified 286 records of which 18 met the eligibility criteria for inclusion. Three studies included patients with tumour-related pain, and 15 studies included patients with pain from chemotherapy-induced peripheral neuropathy (CIPN). Across all studies, 50% (9/18) reported sensory abnormities using thermal detection thresholds (cool and warm), 44% (8/18) reported abnormal mechanical detection thresholds using von-Frey filaments and 39% (7/18) found abnormal pinprick thresholds. Abnormal vibration and thermal pain (heat/cold) thresholds were each reported in a third of included studies. This systematic review highlights the lack of published data characterizing the sensory phenotype of tumour-related cancer pain. This has implications for our understanding of the underlying pathophysiological mechanisms of cancer pain. Understanding the multiple mechanisms driving cancer pain will help to move towards rational individualized analgesic treatment choices. This systematic review found that pain in cancer patients is associated with abnormal sensory responses to thermal, mechanical and pinprick stimuli. However, these findings are based primarily on studies of chemotherapy-induced peripheral neuropathy and data on tumour-related pain are lacking, warranting further research.

Amyloid-β Positivity Predicts Cognitive Decline but Cognition Predicts Progression to Amyloid-β Positivity

BackgroundStage 1 of the National Institute on Aging–Alzheimer’s Association’s proposed Alzheimer’s disease continuum is defined as amyloid-β (Aβ) positive but cognitively normal. Identifying at-risk individuals before Aβ reaches pathological levels could have great benefits for early intervention. Although Aβ levels become abnormal long before severe cognitive impairments appear, increasing evidence suggests that subtle cognitive changes may begin early, potentially before Aβ surpasses the threshold for abnormality. We examined whether baseline cognitive performance would predict progression from normal to abnormal levels of Aβ. MethodsWe examined the association of baseline cognitive composites (Preclinical Alzheimer Cognitive Composite, Alzheimer’s Disease Neuroimaging Initiative (ADNI) memory factor composite) with progression to Aβ positivity in 292 nondemented, Aβ-negative ADNI participants. Additional analyses included continuous cerebrospinal fluid biomarker levels to examine the effects of subthreshold pathology. ResultsForty participants progressed to Aβ positivity during follow-up. Poorer baseline performance on both cognitive measures was significantly associated with increased odds of progression. More abnormal levels of baseline cerebrospinal fluid phosphorylated tau and subthreshold Aβ were associated with increased odds of progression to Aβ positivity. Nevertheless, baseline ADNI memory factor composite performance predicted progression even after controlling for baseline biomarker levels and APOE genotype (Preclinical Alzheimer Cognitive Composite was trend level). Survival analyses were largely consistent: controlling for baseline biomarker levels, baseline Preclinical Alzheimer Cognitive Composite still significantly predicted progression time to Aβ positivity (ADNI memory factor composite was trend level). ConclusionsThe possibility of intervening before Aβ reaches pathological levels is of obvious benefit. Low-cost, noninvasive cognitive measures can be informative for determining who is likely to progress to Aβ positivity, even after accounting for baseline subthreshold biomarker levels.

P1742 Occurrence of right ventricle dysfunction in patients with Brugada syndrome: a follow-up study by echocardiography and electrophysiological examination

Abstract Background Brugada syndrome (BrS) has been characterized by no apparent structural abnormalities in both ventricles, but, recently, the presence of subtle right ventricular (RV) structural abnormalities in patients with BrS has been reported. Purpose The aim of this study was to evaluate the occurrence of RV dysfunction in patients with BrS and their characteristics. Methods We enrolled 49 consecutive patients (54 ± 11 years old) diagnosed with Brs and underwent echocardiography from 2017 to 2018. The echocardiographic parameters and electrophysiological examinations were evaluated including RV size and function such as RV outflow and inflow tract diameter, TAPSE, S’, and FAC. Abnormality threshold for parameters of RV dysfunction is defined as followed: a TAPSE of &amp;lt;17 mm, an S’ of &amp;lt;9.5 cm, and an FAC of &amp;lt;35%. Results Among 49 patients, one patient showed a TAPSE of &amp;lt;17 mm, 5 patients an S’ of &amp;lt;9.5 cm, and 10 patients an FAC of &amp;lt;35%. Evaluating characteristics of Brs patients with RV dysfunction, all patients were divided into 2 groups by the value of RV FAC; 39 patients showing FAC &amp;gt;35% (group A), 10 patients FAC ≤35% (group B). The comparison of each parameter between 2 groups is shown in Table. TAPSE and S’ in group B were lower than in group A. RV inflow tract diameter in group B was larger than in group A, although there was no differences in RV out tract diameter. There were no significant differences in left ventricular parameters, and grade of tricuspid regurgitation. QRS duration prolonged and the rate of ICD implantation was higher in group B than in group A. Moreover, all patients in group B showed RV wall motion abnormalities and the distribution was as followed: diffuse (n = 2), RV mid (n = 2), RV apex (n = 6). Conclusions BrS patients frequently showed RV dysfunction during follow-up, and it may be related to the prolongation of QRS duration. We should pay much attention to the occurrence of RV dysfunction in follow-up echocardiography. Group A (FAC &amp;gt;35%) N = 39 Group B (FAC ≤35%) N = 10 p-value TAPSE, mm 22.9 ± 2.1 20.4 ± 2.6 0.009 S", cm/s 12.8 ± 2.0 11.1 ± 1.4 0.010 RV outflow tract, mm 29.7 ± 4.4 31.2 ± 5.0 0.49 RV mid inflow tract, mm 30.4 ± 2.9 33.8 ± 3.7 0.008 RV basal inflow tract, mm 38.5 ± 3.2 43.7 ± 4.0 0.001 QRS duration, ms 112.9 ± 12.9 136.3 ± 28.4 0.006 Late potential positive, n (%) 25 (64) 8 (80) 0.34 ICD implantation, n (%) 19 (68) 9 (90) 0.019