Genome-wide association analyses using machine learning-based phenotyping reveal genetic architecture of occupational creativity and overlap with psychiatric disorders

Creativity is known to be heritable and exhibits familial aggregation with psychiatric disorders; however, the complex nature of their relationship has not been well-established. In the present study, we demonstrate that using an expanded and validated machine learning (ML)-based phenotyping of occupational creativity (OC) can allow us to further understand the trait of creativity, which was previously difficult to define and study. We conducted the largest genome-wide association study (GWAS) on OC with 241,736 participants from the UK Biobank and identified 25 lead variants that have not yet been reported and three candidate causal genes that were previously associated with educational attainment and psychiatric disorders. We found extensive genetic overlap between OC and psychiatric disorders with mixed effect direction through various post-GWAS analyses, including the bivariate causal mixture model. In addition, we discovered a strongly genetic correlation between our original GWAS and the GWAS adjusted for education years (rg = 0.95). Our GWAS analysis via ML-based phenotyping contributes to the understanding of the genetic architecture of creativity, which may inform genetic discovery and genetic prediction in human cognition and psychiatric disorders.

Facial Expressions Track Depressive Symptoms in Old Age

Facial expressions play a crucial role in the diagnosis of mental illnesses characterized by mood changes. The Facial Action Coding System (FACS) is a comprehensive framework that systematically categorizes and captures even subtle changes in facial appearance, enabling the examination of emotional expressions. In this study, we investigated the association between facial expressions and depressive symptoms in a sample of 59 older adults without cognitive impairment. Utilizing the FACS and the Korean version of the Beck Depression Inventory-II, we analyzed both "posed" and "spontaneous" facial expressions across six basic emotions: happiness, sadness, fear, anger, surprise, and disgust. Through principal component analysis, we summarized 17 action units across these emotion conditions. Subsequently, multiple regression analyses were performed to identify specific facial expression features that explain depressive symptoms. Our findings revealed several distinct features of posed and spontaneous facial expressions. Specifically, among older adults with higher depressive symptoms, a posed face exhibited a downward and inward pull at the corner of the mouth, indicative of sadness. In contrast, a spontaneous face displayed raised and narrowed inner brows, which was associated with more severe depressive symptoms in older adults. These findings suggest that facial expressions can provide valuable insights into assessing depressive symptoms in older adults.

3D Printing-Enabled Design and Manufacturing Strategies for Batteries: A Review

Lithium-ion batteries (LIBs) have significantly impacted the daily lives, finding broad applications in various industries such as consumer electronics, electric vehicles, medical devices, aerospace, and power tools. However, they still face issues (i.e., safety due to dendrite propagation, manufacturing cost, random porosities, and basic & planar geometries) that hinder their widespread applications as the demand for LIBs rapidly increases in all sectors due to their high energy and power density values compared to other batteries. Additive manufacturing (AM) is a promising technique for creating precise and programmable structures in energy storage devices. This review first summarizes light, filament, powder, and jetting-based 3D printing methods with the status on current trends and limitations for each AM technology. The paper also delves into 3D printing-enabled electrodes (both anodes and cathodes) and solid-state electrolytes for LIBs, emphasizing the current state-of-the-art materials, manufacturing methods, and properties/performance. Additionally, the current challenges in the AM for electrochemical energy storage (EES) applications, including limited materials, low processing precision, codesign/comanufacturing concepts for complete battery printing, machine learning (ML)/artificial intelligence (AI) for processing optimization and data analysis, environmental risks, and the potential of 4D printing in advanced battery applications, are also presented.

The efficacy of memory load on speech-based detection of Alzheimer's disease

Introduction

The study aims to test whether an increase in memory load could improve the efficacy in detection of Alzheimer's disease and prediction of the Mini-Mental State Examination (MMSE) score.

Methods

Speech from 45 mild-to-moderate Alzheimer's disease patients and 44 healthy older adults were collected using three speech tasks with varying memory loads. We investigated and compared speech characteristics of Alzheimer's disease across speech tasks to examine the effect of memory load on speech characteristics. Finally, we built Alzheimer's disease classification models and MMSE prediction models to assess the diagnostic value of speech tasks.

Results

The speech characteristics of Alzheimer's disease in pitch, loudness, and speech rate were observed and the high-memory-load task intensified such characteristics. The high-memory-load task outperformed in AD classification with an accuracy of 81.4% and MMSE prediction with a mean absolute error of 4.62.

Discussion

The high-memory-load recall task is an effective method for speech-based Alzheimer's disease detection.

Leveraging genetic overlap between irritability and psychiatric disorders to identify genetic variants of major psychiatric disorders

Irritability is a heritable core mental trait associated with several psychiatric illnesses. However, the genomic basis of irritability is unclear. Therefore, this study aimed to 1) identify the genetic variants associated with irritability and investigate the associated biological pathways, genes, and tissues as well as single-nucleotide polymorphism (SNP)-based heritability; 2) explore the relationships between irritability and various traits, including psychiatric disorders; and 3) identify additional and shared genetic variants for irritability and psychiatric disorders. We conducted a genome-wide association study (GWAS) using 379,506 European samples (105,975 cases and 273,531 controls) from the UK Biobank. We utilized various post-GWAS analyses, including linkage disequilibrium score regression, the bivariate causal mixture model (MiXeR), and conditional and conjunctional false discovery rate approaches. This GWAS identified 15 independent loci associated with irritability; the total SNP heritability estimate was 4.19%. Genetic correlations with psychiatric disorders were most pronounced for major depressive disorder (MDD) and bipolar II disorder (BD II). MiXeR analysis revealed polygenic overlap with schizophrenia (SCZ), bipolar I disorder (BD I), and MDD. Conditional false discovery rate analyses identified additional loci associated with SCZ (number [n] of additional SNPs = 105), BD I (n = 54), MDD (n = 107), and irritability (n = 157). Conjunctional false discovery rate analyses identified 85, 41, and 198 shared loci between irritability and SCZ, BD I, and MDD, respectively. Multiple genetic loci were associated with irritability and three main psychiatric disorders. Given that irritability is a cross-disorder trait, these findings may help to elucidate the genomics of psychiatric disorders.

Erratum: A Comparison Between the Performances of Verbal and Nonverbal Fluency Tests in Discriminating Between Mild Cognitive Impairments and Alzheimer's Disease Patients and Their Brain Morphological Correlates

[This corrects the article on p. 17 in vol. 21, PMID: 35154337.].

Laparoscopic total extra-peritoneal (TEP) inguinal hernia repair under local anesthesia by topical lidocaine injection

PURPOSE

Laparoscopic total extra-peritoneal (TEP) inguinal hernia repair is usually performed under general anesthesia (GA) for muscle relaxation. However, TEP hernia repair may be reluctant in high-risk patients of GA. The aim of this study was to compare the outcomes of the TEP under GA and local anesthesia (LA).

METHODS

We retrospectively analyzed patients with inguinal hernia who underwent TEP under GA or LA in a single center from December 2016 to May 2018. The outcomes, such as demographics, duration of surgery, length of hospital stay, visual analog scale (VAS), and postoperative complications, were compared in each group.

RESULTS

Seventy-six patients with inguinal hernia underwent TEP under GA (n = 52) or LA (n = 24). Total operation time (mean ± standard deviation; GA, 111.6 ± 23.0 min; LA, 76.3 ± 18.0 min; p < 0.001) and length of hospital stay (GA, 38.3 ± 11.6 min; LA, 30.3 ± 15.6 min; p < 0.014) were shorter in LA group compared to GA group. There were no significant differences in postoperative VAS (1 h, p = 0.247; 4 h, p = 0.086; 12 h, p = 0.469; 24 h, p = 0.411), postoperative adverse effects (vomiting, p = 0.570; urinary retention, p = 0.214; headache, p = 0.494), and postoperative complications (seroma, p = 0.348; scrotal edema, p = 0.178; recurrence, p = 0.822) between LA group and GA group.

CONCLUSION

Compared with GA, there were no differences in postoperative pain and complications in patients who underwent TEP hernia repair under LA. Furthermore, in LA group, total operation time and length of hospital stay were shortened.

Effect of active learning and online discussions on the academic performances of dental students

BACKGROUND

COVID-19 caused significant confusion around the world, and dental education was no exception. Therefore, in line with the demands of the times, this study sought to determine the applicability of online active learning to dental education.

METHODS

This study was conducted in the second semester of 2020 at a school of dentistry in a selective university in Korea. A total of 114 dental students were recruited. Participants were assigned to four different groups (lecture and discussion [LD], lecture and discussion with instructor's worksheet [LW], self-study and discussion [SSD], and self-study and discussion with instructor's worksheet [SW]) using the random breakout room function in the Zoom video conference application. Their final test scores were then analyzed using analysis of variance and the online active learning results were compared with the offline learning results.

RESULTS

The scores were highest for the transfer type items in the SSD group, followed by the SW group and the two lecture groups, which had no significant differences. These scores and pattern differences between the groups were similar for all items. The results suggested that studying by oneself rather than simply listening to lectures enhanced the effects of the discussions and led to higher learning outcomes. In addition, the effect of the instructor's intervention in the middle of the discussion varied depending on the pre-learning activities of discussion. As with previous offline experiments, self-study followed by group discussion had higher learning outcomes for both the verbatim and transfer type items.

CONCLUSIONS

In agreement with the Interactive, Constructive, Active, and Passive (ICAP) framework and other active learning theories, the findings clearly indicated that online active learning was applicable to dental students, and when self-study precedes discussion, the learning is richer and the learning outcomes are better.

Association between Residential Greenness and Incidence of Parkinson's Disease: A Population-Based Cohort Study in South Korea

It is widely known that exposure to residential greenness is beneficial for health. However, few studies have analyzed the association between greenery and Parkinson’s disease (PD). We selected 313,355 participants who matched the inclusion criteria from the National Health Insurance Service-National Sample Cohort, followed up from 2007 to 2015. Residential greenness, represented by the normalized difference vegetation index (NDVI), was obtained from satellite measurements. We estimated hazard ratios of PD associated with a 0.1-unit increase in long-term greenness exposure at the district level for the previous 1 year of each year until a censoring/event occurred, using time-varying Cox proportional hazard models, adjusted for individual- and area-level characteristics. During the 2,745,389 person-years of follow-up, 2621(0.8%) participants developed PD. Exposure to higher levels of residential greenness was found to be associated with a decreased risk of PD incidence (21% per 0.1-unit increase, 95% confidence interval (CI): 0.74–0.84). In subgroup analyses, stronger protective effects were observed in participants aged over 50 years, females, overweight/obese participants, non-urban residents, non-smokers, alcoholics, and those with comorbidities. Long-term exposure to greenness was beneficial to incident PD, and our findings could aid in the development of public-health strategies.

A214 SIMPLIFICATION OF CARE FOR HCV IS EFFECTIVE DURING THE COVID PANDEMIC: A RETROSPECTIVE STUDY OF HCV TREATMENT UTILIZING THE BRITISH COLUMBIA HEPATITIS C NETWORK

Background

The COVID-19 pandemic has impacted healthcare access, including to curative treatment for hepatitis C (HCV) infection in the form of direct-acting antivirals (DAAs). A 49% decrease in DAA dispensations in Canada during the pandemic has been reported, but little is known about these treated populations.

Aims

To explore the patient characteristics and treatment patterns in those who were treated for HCV during the COVID pandemic.

Methods

A retrospective chart review was conducted at one site of utilizing the British Columbia Hepatitis C Network. Only patients included into the database were analyzed. Patients started on treatment between 03/17/2020-03/16/2021 were included as the “pandemic group” and patients from the 03/17/2019-03/16/2020 were included as a comparison “pre-pandemic group”. Data were extracted for clinicodemographic variables, laboratory investigations, treatment start date, regimen, and sustained virologic response at 12 weeks (SVR12).

Results

97 patients were treated during the pandemic compared to 143 patients the year prior, representing a 32% decline. Patients treated during the pandemic were predominantly new referrals (n=70, 72% vs n=64, 45% pre-pandemic, p&lt;0.01) and had fewer total appointments (median 2 per patient vs 4 per patient pre-pandemic, p&lt;0.01). There was a median of 1 in-person visit and 1 telehealth appointment per patient during the pandemic (vs median 2 per patient of each type pre-pandemic).

Pandemic patients were younger (mean age 56.0 years vs 59.6 pre-pandemic, p=0.04), and a greater proportion were on opioid agonist therapy (28% vs 13% pre-pandemic, p&lt;0.01). Less transient elastography (TE) was performed during the pandemic (69% vs 89% pre-pandemic). Amongst those with TE scores, a lower proportion of those treated during the pandemic were cirrhotic (13% vs 21% pre-pandemic).

During the pandemic, treatment patterns shifted towards more prescriptions for glecaprevir/pibrentasvir (56% of all prescriptions vs 44% pre-pandemic) and sofosbuvir/velpatasvir (37% vs 29% pre-pandemic). There was slightly less use of sofosbuvir/velpatasvir/voxilaprevir at (2% vs 4% pre-pandemic).

The proportion of patients who completed lab work for SVR was similar during the pandemic (n=83/97, 85.6%) compared to pre-pandemic (n=120/143, 83.9%). Similarly, SVR12 remained high during the pandemic at 98.7% (vs 99.3% pre-pandemic). Of all 97 patients prescribed DAAs during the pandemic, 92 (94.8%) completed treatment.

Conclusions

Less persons were treated during the COVID pandemic, which may deter progress towards HCV elimination targets. Very high SVR12 and treatment completion rates during the pandemic suggest that patients can be effectively treated with less pre-treatment investigations and fewer appointments.

Funding Agencies

None

Genome-wide association study of occupational attainment as a proxy for cognitive reserve

Occupational attainment, which represents middle-age cognitive activities, is a known proxy marker of cognitive reserve for Alzheimer's disease. Previous genome-wide association studies (GWAS) have identified numerous genetic variants and revealed the genetic architecture of educational attainment, another marker of cognitive reserve. However, the genetic architecture and heritability for occupational attainment remain elusive. We performed a large-scale GWAS of occupational attainment with 248,847 European individuals from the UK Biobank using the proportional odds logistic mixed model method. In this analysis, we defined occupational attainment using the classified job levels formulated in the UK Standard Occupational Classification system considering the individual professional skill and academic level. We identified 30 significant loci (P < 5 × 10-8); 12 were novel variants, unassociated with other traits. Among them, four lead variants were associated with genes expressed in brain tissues by expression quantitative trait loci mapping from 10 brain regions: rs13002946, rs3741368, rs11654986, and rs1627527. The single nucleotide polymorphism (SNP)-based heritability was estimated to be 8.5% (s.e. = 0.004) and partitioned heritability was enriched in the central nervous system and brain tissues. Genetic correlation analysis showed shared genetic backgrounds between occupational attainment and multiple traits, including education, intelligence, leisure activities, life satisfaction, and neuropsychiatric disorders. In two-sample Mendelian randomization (MR) analysis, we demonstrated that high occupation levels were associated with reduced risk for Alzheimer's disease (OR = 0.78, 95% CI = 0.65-0.92 in inverse variance weighted (IVW) method; OR = 0.73, 95% CI = 0.57-0.92 in the weighted median (WM) method). This causal relationship between occupational attainment and Alzheimer's disease was robust in additional sensitivity analysis that excluded potentially pleiotropic SNPs (OR = 0.72, 95% CI = 0.57-0.91 in the IVW method; OR = 0.72, 95% CI = 0.53-0.97 in the WM method). Multivariable MR confirmed that occupational attainment had an independent effect on the risk for Alzheimer's disease even after taking educational attainment into account (OR = 0.72, 95% CI = 0.54-0.95 in the IVW method; OR = 0.68, 95% CI = 0.48-0.97 in the WM method). Overall, our analyses provide insights into the genetic architecture of occupational attainment and demonstrate that occupational attainment is a potential causal protective factor for Alzheimer's disease as a proxy marker of cognitive reserve.

A164 PATTERNS IN MEDICAL THERAPY AND CLINICAL OUTCOMES IN PATIENTS WITH CONCOMITANT INFLAMMATORY BOWEL DISEASE AND PRIMARY SCLEROSING CHOLANGITIS: A SINGLE CENTRE RETROSPECTIVE ANALYSIS

Background

Inflammatory bowel disease (IBD) in patients with primary sclerosing cholangitis (PSC) is characterized by pancolitis with rectal sparing and is associated with an increased risk of colorectal and biliary malignancies. Currently, pharmacologic management of IBD in the setting of PSC is the same as in IBD alone.

Aims

To assess patterns in medical therapy, and incidence of adverse outcomes in patients with concomitant IBD and PSC.

Methods

A retrospective review was conducted on all PSC-IBD patients followed between January 2010 and June 2018. The Endoscopic Mayo Score was used to grade IBD severity in PSC-ulcerative colitis (UC).

Results

69 patients were identified, 44 (63.8%) were male. The mean ages of IBD and PSC diagnosis were 28.6 (SD 14.9) and 37.0 (SD 18.9) years, respectively. The median length of follow up was 12 (range 2–49) years. 52 (75.4%) patients had UC, and 17 (24.6%) had Crohn’s disease (CD). 28 (87.5%) PSC-UC patients had pancolitis, and 4 (12.5 %) had proctitis. Among those with pancolitis, 8 (28.6%) had relative rectal sparing. 4 (14.3%) patients had more severe inflammation proximally, whereas only 1 (3.6%) had more severe distal inflammation. 23 (82.1%) patients had the same degree of inflammation throughout. 14 (93.3%) PSC-CD patients had colitis/ileocolitis and 1 (6.7%) had ileitis. Among those with PSC-UC, 16 (50.0%), 12 (37.5%), and 4 (12.5%) patients had grade 1, 2, and 3 disease, respectively. 62 (89.9%) PSC-IBD patients were treated with aminosalicylates, and 26 (37.7%) with biologics at some point in their IBD course. 26 (37.7%) were treated with aminosalicylates alone. 4 (5.8%) did not require any IBD therapy. Cholangiocarcinoma, colorectal cancer, and gallbladder cancer developed in 8 (11.6%), 1 (1.4%), and 1 (1.4%) PSC-IBD patients, respectively. 16 (23.2%) patients required partial or total colectomy. Indication for surgery was inflammation or stenosis, dysplasia, and neoplasia in 13 (81.3%), 2 (12.5%), and 1 (6.3%) patients, respectively.

Conclusions

The majority of this cohort had UC with mild disease activity. Pancolitis was common, with frequent rectal sparing and more severe right-sided inflammation. Despite the predominance of low-grade colitis, a large portion of patients required treatment with biologics. The incidence of adverse outcomes underscores the need for strict adherence to recommended surveillance practices. Low grade endoscopic activity, typical of the quiescent IBD course in PSC-IBD, may mask low grade histologic inflammation, which in turn may contribute to the increased risk of colonic neoplasia. Further studies are needed to determine the best management strategy for IBD in patients with PSC.

Funding Agencies

None

A208 PREDICTORS OF OUTCOMES IN PSC: RETROSPECTIVE ANALYSIS OF TWO TERTIARY CARE CENTERS IN BC

Background

Primary sclerosing cholangitis (PSC) is a chronic inflammatory disorder of the bile ducts. PSC can rapidly progress to cholangiocarcinoma and death. Many clinical features of PSC, as well as its relationship with diseases such as IBD, remain ill-defined. These features are important for disease modeling and clinical trial design.

Aims

To identify features of PSC that may aid in disease modeling and outcomes prediction.

Methods

Patients with a diagnosis of PSC with visits between 2012 and 2018 were identified and data were extracted. Survival analysis was performed, with time defined as time of PSC diagnosis to time at clinical endpoint. The clinical endpoint for survival analysis was defined as development of cholangiocarcinoma, liver transplantation or death. Univariate and multivariate Cox-regression was then performed.

Results

169 patients (99 male, 70 female) were identified. Of these, 102 (60.4%) had a diagnosis of IBD (84 UC). 138 were Caucasian, 9 East Asian, 9 South Asian and 13 Middle East. Mean age at PSC diagnosis was 39.3, IBD diagnosis 29.3 years. Mean time to next diagnosis in those with PSC-IBD was 7.7 years. Of those with PSC-IBD, IBD preceded the diagnosis of PSC in 69 (67.6%) patients. 22 (13.0%) had concurrent liver disease, including 14 AIH and 1 PBC overlap. In those with UC, disease was most often pancolitis (57.8%), with noticeable rate of backwash ileitis (23.3%). There were 26 patients with current or prior use of Infliximab, 14 with Humira, and 6 with Vedolizumab. 28 (16.6%) patients had a partial or total colectomy. 35 (20.7%) patients had diagnoses of cancer, including 16 cholangiocarcinoma, 2 gall bladder carcinoma, and 4 colorectal. 33 (19.5%) patients received liver transplant, and 31 (18.3%) died. Most frequent cause of death was cholangiocarcinoma (12, 38.7%). Univariate analysis identified increased age at PSC diagnosis, presence of IBD, increased age at IBD diagnosis, diagnosis of IBD prior to PSC, increased time from diagnosis of IBD to PSC, diagnosis of UC as opposed to Crohn’s, and lack of Infliximab use as significant predictors of our clinical endpoints (p&lt;0.05). Multivariate analysis only identified increased age at PSC diagnosis, presence of IBD, and diagnosis of IBD prior to PSC as predictors.

Conclusions

PSC affects persons of various ethnic backgrounds. Diagnosis of IBD appears to precede PSC in most PSC-IBD cases, and the temporal relationship may impact outcomes, possibly due to delayed diagnosis of PSC. UC has a worse disease course than Crohn’s. Cholangiocarcinoma still accounts for a large burden of overall death in PSC, and strategies for early diagnosis should be explored. More studies are required to delineate the relationship between biologic use and PSC outcomes. The major limitation of our study is the smaller sample size that may have limited statistical power.

Funding Agencies

NoneNone

Uniform spatial pooling explains topographic organization and deviation from receptive-field scale invariance in primate V1

Receptive field (RF) size and preferred spatial frequency (SF) vary greatly across the primary visual cortex (V1), increasing in a scale invariant fashion with eccentricity. Recent studies reveal that preferred SF also forms a fine-scale periodic map. A fundamental open question is how local variability in preferred SF is tied to the overall spatial RF. Here, we use two-photon imaging to simultaneously measure maps of RF size, phase selectivity, SF bandwidth, and orientation bandwidth—all of which were found to be topographically organized and correlate with preferred SF. Each of these newly characterized inter-map relationships strongly deviate from scale invariance, yet reveal a common motif—they are all accounted for by a model with uniform spatial pooling from scale invariant inputs. Our results and model provide novel and quantitative understanding of the output from V1 to downstream circuits.

Two-photon imaging in macaque V1 captured maps of tuning selectivity for four spatial parameters, all of which correlated with peak spatial frequency. These inter-map relationships reveal a common motif—they are described by uniform spatial pooling from a family of scale invariant Gabor receptive fields.

Analyzing Facial and Eye Movements to Screen for Alzheimer's Disease

Brain disease can be screened using eye movements. Degenerative brain disorders change eye movement because they affect not only memory and cognition but also the cranial nervous system involved in eye movement. We compared the facial and eye movement patterns of patients with mild Alzheimer’s disease and cognitively normal people to analyze the neurological signs of dementia. After detecting the facial landmarks, the coordinate values for the movements were extracted. We used Spearman’s correlation coefficient to examine associations between horizontal and vertical facial and eye movements. We analyzed the correlation between facial and eye movements without using special eye-tracking equipment or complex conditions in order to measure the behavioral aspect of the natural human gaze. As a result, we found differences between patients with Alzheimer’s disease and cognitively normal people. Patients suffering from Alzheimer’s disease tended to move their face and eyes simultaneously in the vertical direction, whereas the cognitively normal people did not, as confirmed by a Mann–Whitney–Wilcoxon test. Our findings suggest that objective and accurate measurement of facial and eye movements can be used to screen such patients quickly. The use of camera-based testing for the early detection of patients showing signs of neurodegeneration can have a significant impact on the public care of dementia.

A136 PREDICTIVE FACTORS OF CIRRHOSIS IN HCV PATIENTS WITH LOW PRE-TREATMENT APRI AND/OR FIB-4 SCORES

Background

It is essential to evaluate the stage of hepatic fibrosis prior to the initiation of HCV therapy. In addition to being a major prognostic factor, the presence of cirrhosis requires monitoring for hepatocellular carcinoma (HCC), esophageal varices, and decompensated liver disease. In some cases the presence of cirrhosis may affect the choice of therapy. In tertiary hepatology clinics, transient elastography (TE) is routinely used to assess fibrosis; however access to TE is limited. Fibrosis-4 (FIB4) and AST-to-platelet ratio index (APRI) are simple, easily available non-invasive methods of fibrosis measurement based on routine serum biomarkers. Studies evaluating HCV treatment pathways have reported that the use of FIB4 and APRI are cost-effective strategies for excluding cirrhosis thereby reducing the need for TE prior to treatment. Although the NPV of these tests are well described, a minority of patients will have advanced fibrosis despite low APRI and/or FIB4 scores.

Aims

To investigate predictive factors of cirrhosis in HCV patients with low pre-treatment APRI and/or FIB-4 scores.

Methods

Retrospective observational study with data obtained from the Pacific Gastroenterology Associates (PGA), a tertiary care outpatient Gastroenterology clinic located in Vancouver, British Columbia. Inclusions: Chronic HCV patients treated between Jan 2015 to 2019, pre-treatment TE values ≥12.5 kPa, FIB-4 &lt;1.45 and/or APRI &lt;0.7. Exclusions: those without cirrhosis, or incomplete evaluation prior to HCV treatment. Cirrhosis was defined as those with TE ≥12.5 kPa with clinical, radiographic, or pathologic features of cirrhosis.

Results

52 patients were identified. 11 patients did not have clinical, radiographic, or pathologic features of cirrhosis and 3 patients were excluded for insufficient data. Thus, 39 patients were included in multivariate analysis. The mean age was 59 years and 66% (25/38) were male gender. 10% (4/38) were Genotype 3 (G3). Presence of G3 was not included in the multivariate analysis due to low number of observations.

Conclusions

Generally, an APRI &lt;0.7 and FIB-4 &lt;1.45 have good test characteristics for excluding fibrosis. Our study demonstrates that patients with obesity, dyslipidemia, excessive alcohol use, or known steatosis on ultrasound may have cirrhosis despite low serum biomarker scores. Co-existence of other liver diseases such as alcohol related or non-alcoholic fatty liver disease (NAFLD) should prompt further evaluation for fibrosis assessment beyond biomarkers as these persons may have more advanced liver disease.

Funding Agencies

None

A186 HEPATIC STEATOSIS PREDICTS FIBROSIS IN LONG-TERM METHOTREXATE USE

Background

Methotrexate (MTX) is effective for dermatologic and rheumatologic conditions such as psoriasis (Ps), psoriatic arthritis (PsO) and rheumatoid arthritis (RA). Long-term MTX use may be complicated by hepatic fibrosis, although patient, disease factors and the mechanism remain unclear. Transient elastography (TE) is a non-invasive measure of hepatic fibrosis that is often used as surveillance in this patient population.

Patients with Ps and PsO have higher rates of non-alcoholic fatty liver disease. The controlled attenuation parameter (CAP) measurement is a non-invasive test that correlates with histologic degree of steatosis. To our knowledge, no studies have evaluated hepatic steatosis via CAP scores in MTX use.

Aims

To determine the prevalence of steatosis and significant fibrosis (F≥stage 2) in persons on MTX therapy and to determine the predictive factors for these events.

Methods

A single centred retrospective cohort study was performed. Patients on &gt;6 months of MTX for a dermatologic or rheumatologic disease who had undergone TE from January 2015 to September 2019 were included. Demographic variables, laboratory investigations, TE and CAP scores were collected. Multivariate analysis was performed to determine predictors of steatosis and fibrosis.

Results

A total of 177 patients on methotrexate were included. Ps was the most frequent diagnosis (n=52) followed by RA (n=50) and PsO (n=38). Steatosis (CAP≥245 dB/m) was present in 73.9% of patients. Patients with steatosis had significantly more fibrosis and a higher BMI than those without steatosis (CAP&lt;245 dB/m). Higher CAP score was correlated with increased lifetime dose of methotrexate by Pearson correlation analysis (r=0.48, p=0.001) (n=85 patients). Multivariate regression analysis revealed that diabetes mellitus (OR 10.5, 95% CI 1.38–80.60), hypertension (OR 4.97, 95% CI 1.66–14.84), and BMI&gt; 30 (OR 10.1, 95% CI 1.88–37.14) were predictors of steatosis (CAP≥245 dB/m). Predictors of METAVIR≥F2 (TE≥8.0 kPa) by multivariate regression analysis included CAP score of ≥270 (OR 8.36, 95% CI 1.88–37.14), diabetes mellitus (OR 2.85, 95% CI 1.09–7.48), hypertension (OR 5.4, 95% CI 2.23–13.0), dyslipidemia (OR 3.71, 95% CI 1.50–9.18) and alcohol use (OR 3.06, 95% CI 1.2–7.49).

Conclusions

In patients on MTX for rheumatologic and dermatologic diseases, hepatic steatosis was common and predicted significant fibrosis. Additionally, increasing MTX exposure is correlated with steatosis. Features of the metabolic syndrome including diabetes, hypertension or obesity were predictors of both steatosis and fibrosis (F≥2). Further study is needed to evaluate if steatosis is a mechanism by which fibrosis occurs in patients on MTX, or if it due to other patient factors.

Funding Agencies

None

Differences in Facial Expressions between Spontaneous and Posed Smiles: Automated Method by Action Units and Three-Dimensional Facial Landmarks

Research on emotion recognition from facial expressions has found evidence of different muscle movements between genuine and posed smiles. To further confirm discrete movement intensities of each facial segment, we explored differences in facial expressions between spontaneous and posed smiles with three-dimensional facial landmarks. Advanced machine analysis was adopted to measure changes in the dynamics of 68 segmented facial regions. A total of 57 normal adults (19 men, 38 women) who displayed adequate posed and spontaneous facial expressions for happiness were included in the analyses. The results indicate that spontaneous smiles have higher intensities for upper face than lower face. On the other hand, posed smiles showed higher intensities in the lower part of the face. Furthermore, the 3D facial landmark technique revealed that the left eyebrow displayed stronger intensity during spontaneous smiles than the right eyebrow. These findings suggest a potential application of landmark based emotion recognition that spontaneous smiles can be distinguished from posed smiles via measuring relative intensities between the upper and lower face with a focus on left-sided asymmetry in the upper region.

Active learning through discussion: ICAP framework for education in health professions

BACKGROUND

The ICAP framework based on cognitive science posits four modes of cognitive engagement: Interactive, Constructive, Active, and Passive. Focusing on the wide applicability of discussion as interactive engagement in medical education, we investigated the effect of discussion when it was preceded by self-study and further investigated the effect of generating questions before discussions.

METHODS

This study was conducted in the second semester of 2018 and was participated in by 129 students majoring in health professions, including medicine, dentistry, veterinary medicine, and nursing. The students were assigned to four different trial groups and were asked to fill out a Subjective Mental Effort Questionnaire after completing each session. Their performance in posttest scores was analyzed using Bonferroni test, and mental effort was analyzed using mediation analysis.

RESULTS

These results indicated that the self-study and question group had the highest performance and that the lecture and summary group had the lowest performance when comparing the total score. Using the analysis of mental effort, it was confirmed that the relationship between different study conditions and post-test performance was mediated by mental effort during test.

CONCLUSIONS

Our findings support the ICAP framework and provide practical implications for medical education, representing the fact that students learn more when they are involved in active learning activities, such as self-study and question generation, prior to discussions.

Twelve-day medium pumping into tubular cell-laden scaffold using a lab-made PDMS connector

In the current study, a method is proposed to supply culture medium into a two-layered cell-laden tubular scaffold in order to enhance cell proliferation, confluence, and viability. The two-layered cell-laden tubular scaffold was made of calcium-alginate mixed with fibroblast cells (NIH/3T3) using a lab-made double- coaxial laminar-flow generator. Afterwards, the tubular scaffold was connected to a syringe pump system using a polydimethylsiloxane (PDMS) micro-connector for long-term cell culture. Three medium pumping conditions were applied and compared: a heart-beat-mimicking pumping (20 µL/s, 1 s period, and 50 % pulse width), a continuous pumping (20 µL/s) and a non-pumping. Non-leaky connections between the tubular scaffolds and the micro-connector outlet were sustained for 13.5 ± 0.83 d in heartbeat-mimicking pumping and 11.8 ± 0.33 d in continuous pumping condition, due to the elasticity of the tubular scaffolds. Importantly, the two pumping conditions resulted in more cell proliferation, confluence, and viability than the non-pumping condition. Furthermore, analysis of newly-produced type-I collagen matrix indicated that the cells under the two pumping conditions formed a tissue-like structure. The proposed technique could further be applied to vascular co-culturing for vascular engineered tissue.

Cognitive Profiling Related to Cerebral Amyloid Beta Burden Using Machine Learning Approaches

Background: Cerebral amyloid beta (Aβ) is a hallmark of Alzheimer’s disease (AD). Aβ can be detected in vivo with amyloid imaging or cerebrospinal fluid assessments. However, these technologies can be both expensive and invasive, and their accessibility is limited in many clinical settings. Hence the current study aims to identify multivariate cost-efficient markers for Aβ positivity among non-demented individuals using machine learning (ML) approaches.

Methods: The relationship between cost-efficient candidate markers and Aβ status was examined by analyzing 762 participants from the Alzheimer’s Disease Neuroimaging Initiative-2 cohort at baseline visit (286 cognitively normal, 332 with mild cognitive impairment, and 144 with AD; mean age 73.2 years, range 55–90). Demographic variables (age, gender, education, and APOE status) and neuropsychological test scores were used as predictors in an ML algorithm. Cerebral Aβ burden and Aβ positivity were measured using ¹⁸F-florbetapir positron emission tomography images. The adaptive least absolute shrinkage and selection operator (LASSO) ML algorithm was implemented to identify cognitive performance and demographic variables and distinguish individuals from the population at high risk for cerebral Aβ burden. For generalizability, results were further checked by randomly dividing the data into training sets and test sets and checking predictive performances by 10-fold cross-validation.

Results: Out of neuropsychological predictors, visuospatial ability and episodic memory test results were consistently significant predictors for Aβ positivity across subgroups with demographic variables and other cognitive measures considered. The adaptive LASSO model using out-of-sample classification could distinguish abnormal levels of Aβ. The area under the curve of the receiver operating characteristic curve was 0.754 in the mild change group, 0.803 in the moderate change group, and 0.864 in the severe change group, respectively.

Conclusion: Our results showed that the cost-efficient neuropsychological model with demographics could predict Aβ positivity, suggesting a potential surrogate method for detecting Aβ deposition non-invasively with clinical utility. More specifically, it could be a very brief screening tool in various settings to recruit participants with potential biomarker evidence of AD brain pathology. These identified individuals would be valuable participants in secondary prevention trials aimed at detecting an anti-amyloid drug effect in the non-demented population.

Bioinks and bioprinting technologies to make heterogeneous and biomimetic tissue constructs

The native tissues are complex structures consisting of different cell types, extracellular matrix materials, and biomolecules. Traditional tissue engineering strategies have not been able to fully reproduce biomimetic and heterogeneous tissue constructs because of the lack of appropriate biomaterials and technologies. However, recently developed three-dimensional bioprinting techniques can be leveraged to produce biomimetic and complex tissue structures. To achieve this, multicomponent bioinks composed of multiple biomaterials (natural, synthetic, or hybrid natural-synthetic biomaterials), different types of cells, and soluble factors have been developed. In addition, advanced bioprinting technologies have enabled us to print multimaterial bioinks with spatial and microscale resolution in a rapid and continuous manner, aiming to reproduce the complex architecture of the native tissues. This review highlights important advances in heterogeneous bioinks and bioprinting technologies to fabricate biomimetic tissue constructs. Opportunities and challenges to further accelerate this research area are also described.

Water-adaptive and repeatable self-healing polymers bearing bulky urea bonds

A crosslinked copolymer having a reversible covalent bond between a bulky amine and an isocyanate presents reshapable, repeatable, and water-adaptive self-healing properties.

A micropatterned elastomeric surface with enhanced frictional properties under wet conditions and its application

Engineered surfaces that have high friction under wet or lubricated conditions are important in many practical applications. However, it is not easy to achieve stable high friction under wet conditions because a layer of fluid prevents direct solid-solid contact. Here, we report a micropatterned elastomeric surface with superior wet friction. The surface has unique arch-shaped microstructures arrayed in a circle on the surface to provide high friction on wet or flooded surfaces. The arch-shaped micropatterned surface exhibits remarkably enhanced and stable friction under wet conditions, surpassing even the performance of the hexagonal patterns of tree frogs, owing to the large contact surface and the optimal shape of drainage channels. Robotic substrate transportation systems equipped with the micropatterned surfaces can manipulate a delicate wet substrate without any sliding in a highly stable and reproducible manner, demonstrating the superior frictional capabilities of the surface under wet conditions.