A Drug Repurposing Approach Reveals Targetable Epigenetic Pathways in Plasmodium vivax Hypnozoites

Radical cure of Plasmodium vivax malaria must include elimination of quiescent 'hypnozoite' forms in the liver; however, the only FDA-approved treatments are contraindicated in many vulnerable populations. To identify new drugs and drug targets for hypnozoites, we screened the Repurposing, Focused Rescue, and Accelerated Medchem (ReFRAME) library and a collection of epigenetic inhibitors against P. vivax liver stages. From both libraries, we identified inhibitors targeting epigenetics pathways as selectively active against P. vivax and P. cynomolgi hypnozoites. These include DNA methyltransferase (DNMT) inhibitors as well as several inhibitors targeting histone post-translational modifications. Immunofluorescence staining of Plasmodium liver forms showed strong nuclear 5-methylcystosine signal, indicating liver stage parasite DNA is methylated. Using bisulfite sequencing, we mapped genomic DNA methylation in sporozoites, revealing DNA methylation signals in most coding genes. We also demonstrated that methylation level in proximal promoter regions as well as in the first exon of the genes may affect, at least partially, gene expression in P. vivax. The importance of selective inhibitors targeting epigenetic features on hypnozoites was validated using MMV019721, an acetyl-CoA synthetase inhibitor that affects histone acetylation and was previously reported as active against P. falciparum blood stages. In summary, our data indicate that several epigenetic mechanisms are likely modulating hypnozoite formation or persistence and provide an avenue for the discovery and development of improved radical cure antimalarials.

ANXIETY SYNDROMES IN ADOLESCENTS WITH OPERATIONAL RESPIRATORY CONDITIONS: A PROSPECTIVE STUDY

Aim - determining the prevalence of anxiety disorders and their effect on disease progression and quality of life in adults with organic illnesses and functional disorders of the respiratory system treated in a pulmonology environment. A total of 135 young adults between the ages of 13 and 17 were analyzed. There were a total of 46 adolescents diagnosed with somatoform respiratory disorders (SRD), 45 adolescents diagnosed with bronchial asthma (BA), and 44 adolescents diagnosed with pneumonia. The Spielberger-Khanin anxiety questionnaire and the Nijmegen hyperventilation syndrome (HVS) scale were used for the research and diagnosis, respectively. The quality of life was measured using the asthma quality of life questionnaire (AQLQ). In comparison to adults with asthma (33.2%) and pneumonia (32.3%), adults with SRD (34.5%). There were mild immediate associations between the Spielberger scale and the Nijmegen HVS questionnaire for both trait and state anxiety, and mild inverse correlations between the Spielberger scale and the AQLQ for both state and trait anxiety. Adolescents with anxiety had a higher prevalence of trauma, pain, and social issues than their non-anxious counterparts who were referred to psychiatry. In adolescents, 5.1% had severe trait anxiety, and 19.3% had severe condition anxiety. Adolescents with SRD were twice as likely to suffer from extreme state and trait anxiety as the general population. It is hypothesized that anxiety problems are at the root of HVS and contribute to adults' dissatisfaction with their quality of life due to lung ailments. Although certain adolescents with anxiety disorders were referred for anxiety, this data nevertheless lends credence to the idea that using standardized and structured instruments regularly might help increase accuracy and detection rates in the clinic, regardless of the reason for referral. Complete evaluations are essential for this patient population due to the intricacy of their symptoms.

Single Institute Experience Treating Uterine Carcinosarcoma: Outcome Analysis

PURPOSE/OBJECTIVE(S)

Uterine carcinosarcoma (UCS) is rare with a poor prognosis. We report over 10 years' experience, reporting prognostic and predictive factors for overall survival (OS) and disease-free survival (DFS).

MATERIALS/METHODS

Patient, tumor, treatment and relapse characteristics of 168 women with stages I-IVB UCS treated at our institute between 2010 and 2020 were analyzed. OS and DFS at 2 and 5 years were the primary outcomes, estimated with Kaplan-Meier. The benefit of adjuvant chemotherapy and radiotherapy in the curative cohort was estimated using the log rank test.

RESULTS

Median follow up was 23 months (range 1-137 months). 34% had FIGO stage IA disease, 10% IB, 8% II. 16% IIIA-IIIC1, and 10% IIIC2 and 22% IVB. The overall 2-year OS was 52% and 5-year OS 30%. 2-year OS by FIGO stage were: IA 66%; IB 63%; II 54%; IIIA-IIIC1 54%; IIIC2 45%; IVB 26%. Within the curative cohort who were surgically staged, 2-year DFS was 47% and 5-year was 30%. 2-year DFS were 61% in IA disease, 53% IB, 12% II, 51% IIIA-IIIC1, and 45% IIIC2 and 4% IVB. A greater risk of death was conferred by lack of adjuvant treatment (lack of chemo > lack of radiotherapy). The most common chemotherapy regimen used was Carboplatin Paclitaxel and pelvic radiotherapy 45Gy 25F over 5 weeks. The combination of surgery and chemotherapy +/- radiotherapy significantly improved OS compared to surgery +/- radiotherapy (HR 0.5 with CI 0.3 - 0.9) p<0.05. Radiotherapy improved OS compared to surgery only (HR 0.4 with CI 0.2 - 1.1) p<0.05. Relapse rate in all patients following curative treatment is 72% within year 1 and 86% within year 2 from diagnosis. In 52 patients with stage 1A disease treated with surgery +/- radiotherapy only, 42.4% relapsed, median time to relapse was 8 months from diagnosis. Relapse occurred despite 69.2 % stage 1A patients receiving adjuvant pelvic EBRT and in these patients relapse within the pelvis occurred in 50%.

CONCLUSION

This study constitutes the largest retrospective analyses of long-term mortality outcomes in UCS and confirms poor outcomes despite curative surgery and adjuvant therapy. Most patients relapse within the first year following curative treatment. The use of adjuvant chemotherapy improves OS in all stages. In stage 1A disease 42 % patients relapse locally and distantly. This is an area of controversy and this data would strongly suggest that the addition of adjuvant paclitaxel-carboplatin or cisplatin-doxorubicin chemotherapy to EBRT should be considered in all patients including earliest stage disease.

Single Institute Experience with MRI-Guided Adaptive Brachytherapy for Locally Advanced Cervix Cancer: Long Term Outcomes and Toxicity Analysis

PURPOSE/OBJECTIVE(S)

We report over 10 years' experience of MRI-guided adaptive brachytherapy (MRIGABT) in locally advanced cervix cancer (LACC).

MATERIALS/METHODS

A total of 162 patients with LACC FIGO stage IB-IVB were treated at our institute between 2010 and 2020. Treatment consisted of chemoradiotherapy (weekly intravenous cisplatin 40 mg/m², 5 cycles, 1 day per cycle, 45-50.4 Gy external beam radiotherapy (EBRT) in 1·8-2 Gy fractions, followed by MRIGABT. Target volume definition and dose reporting for MRIGABT was according to GEC-ESTRO recommendations. MRIGABT dose prescription was according to our institutional practice. Overall survival (OS) and disease-free survival (DFS) were the primary endpoints. Kaplan-Meier estimates were calculated for OS and DFS at 2, 5 and 10-years. Organ-specific late toxicity grade ≥3 (≥G3) (CTCAEv5.0) was reported, alongside rates of bowel fistula, stricture, and perforation. Using logistic regression, we explored the relationship between EQD2 D2cc bladder and ≥G3 genitourinary (GU) toxicity. We compared patient proportions developing ≥ G3 GU toxicity in those who received EQD2 ≥85 Gy versus <85 Gy. We examined the following predictors of ≥G3 gastrointestinal (GI) toxicity: EQD2 dose (≥65 Gy versus <65 Gy), pre-existing bowel conditions, nodal boost, and extended field EBRT.

RESULTS

Median follow up was 4.7 years (IQR 3.3-7.1 years). Median EBRT dose was 50.4 Gy (IQR 50.4-50.4 Gy); 91% received chemotherapy. Median high-risk clinical target volume (HRCTV) was 23.6 cm3 (IQR 16.6-31.3 cm3). Median doses were as follows; D90 HRCTV 88.9 Gy EQD210 (IQR 84.1-91.3 Gy), median D2cc bladder 81.6 (IQR 76.9-85.7 Gy), rectum 62.2 (IQR 57.9-65.3 Gy), sigmoid 67.4 (IQR 60.8-71.1 Gy), and bowel 55 (IQR 49.9-63.2 Gy), (all EQD23). The 2, 5 and-10-year OS were 98%, 80% and 75%. The 2, 5 and 10-year DFS were 98%, 75% and 60%. Late toxicity ≥G3 was 9% GU, 6% GI and 3% vaginal. There was a significant relationship between EQD2 and ≥G3 GU toxicity (OR: 1.11, 95% CI: 1.01-1.25; P = 0.04). When comparing those who received EQD2≥ 85Gy versus <85Gy, higher doses were associated with a greater proportion of ≥G3 GU toxicity (13% vs 6%). No significant predictors of ≥ G3 GI toxicity were observed.

CONCLUSION

We observed excellent LC and OS. A significant relationship was found between EQD2 >85 Gy and bladder toxicity, although ≥G3 toxicity was low. We did not identify predictors of bowel toxicity. New predictors of bowel toxicity are required. Mean EBRT dose, D1.0 cc rectum, sigmoid and bowel are being investigated further.

PfMORC protein regulates chromatin accessibility and transcriptional repression in the human malaria parasite, P. falciparum

The environmental challenges the human malaria parasite, Plasmodium falciparum, faces during its progression into its various lifecycle stages warrant the use of effective and highly regulated access to chromatin for transcriptional regulation. Microrchidia (MORC) proteins have been implicated in DNA compaction and gene silencing across plant and animal kingdoms. Accumulating evidence has shed light into the role MORC protein plays as a transcriptional switch in apicomplexan parasites. In this study, using CRISPR/Cas9 genome editing tool along with complementary molecular and genomics approaches, we demonstrate that PfMORC not only modulates chromatin structure and heterochromatin formation throughout the parasite erythrocytic cycle, but is also essential to the parasite survival. Chromatin immunoprecipitation followed by deep sequencing (ChIP-seq) experiments suggest that PfMORC binds to not only sub-telomeric regions and genes involved in antigenic variation but is also most likely a key modulator of stage transition. Protein knockdown experiments followed by chromatin conformation capture (Hi-C) studies indicate that downregulation of PfMORC induces the collapse of the parasite heterochromatin structure leading to its death. All together these findings confirm that PfMORC plays a crucial role in chromatin structure and gene regulation, validating this factor as a strong candidate for novel antimalarial strategies.

THE IMPACT OF CLIMATE CHANGE ON INFECTIOUS DISEASES: A COMPREHENSIVE ANALYSIS OF VECTOR-BORNE DISEASES, WATER-BORNE DISEASES, AND PUBLIC HEALTH STRATEGIES

Climate change is long-term modifications to weather patterns and a rise in extreme weather events. It might modify the hazard to human health and exacerbate current problems. The article explores the scientific data in a description of the effects of Infectious diseases in humans and climate change. It identifies scientific advancements and gaps in potential responses from human civilization and how it might prepare for the changes that come with it by adjusting to them. The impact reflects three aspects, such as climate variables, selected infectious diseases, and infectious disease components. This study demonstrates how vulnerable people are to any ill consequences that climate change may have on their health. Humans can actively influence controllable correlated health impacts by taking proactive measures, such as increasing our understanding of the detrimental effects associated with specific diseases and the patterns in climate change. We can also carefully distribute technology and resources, encouraging exercise and public awareness. It is advised to take the following adaption measures: Considering how infectious diseases and climate change are not the only things that science has discovered and create locally efficient early warning systems for those effects to produce more scientific justifications and go beyond scientific reports. Improve prediction of the spatiotemporal processes behind climate change and changes in infectious illnesses connected at different temporal and spatial scales.

A142 APPROPRIATENESS OF POST-ENDOSCOPY CARE IN PATIENTS PRESENTING WITH FOOD BOLUS IMPACTIONS OVERNIGHT: A POPULATION-BASED MULTICENTER COHORT STUDY

Background

Appropriate management of esophageal food bolus impactions includes endoscopic evaluation and follow-up for potential underlying esophageal pathology. Patients who present with impactions at night may not receive optimal long-term post-endoscopy care due to patient-, physician-, or system-related factors.

Purpose

We aimed to evaluate the appropriateness of care for patients who present with food bolus impactions after regular daytime hours.

Method

We conducted a retrospective, population-based, multi-center cohort study of adult patients undergoing endoscopy for food impaction between 19:00-06:59 from 2016-2018 in the Calgary Health Zone, Canada. Appropriate post-endoscopy care was defined by a composite of a follow-up clinic visit, repeat endoscopy, other appropriate investigations (e.g., manometry), or appropriate medical treatment (e.g., proton pump inhibitor). Predictors of inappropriate care were assessed using multivariable logistic regression, expressed as adjusted odds ratios (aOR) with 95% confidence intervals (CI).

Result(s)

A total of 323 patients underwent an after-hours or overnight endoscopy for food bolus impaction. 25.4% (82/323) of patients did not receive appropriate post-endoscopy care. Predictors of inappropriate care included rural residence (aOR 2.66 [95% CI: 1.18-6.01], p=0.02), first food bolus presentation (aOR 2.38 [95% CI: 1.04-5.44], p=0.04), and absence of a specific pathology during the index procedure (aOR 3.01 [95% CI: 0.97-9.29], p=0.05), suggesting a potential association with clinician cognitive bias. Among patients who were followed, 18.9% (35/185) had a change in the original diagnosis.

Image

Conclusion(s)

One quarter of patients presenting with a food bolus impaction at night do not receive appropriate post-endoscopy care. System-based interventions should target this high-risk population as the diagnosis and management may change with follow-up.

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Disclosure of Interest

None Declared

The effectiveness of prenatal and postnatal home visits by paramedical professionals and women's group meetings in improving maternal and child health outcomes in low and middle-income countries: a systematic review and meta-analysis

OBJECTIVE

To assess the effectiveness of prenatal and postnatal home visits (HVs) and women group meetings (WGMs) by paramedical professionals to improve maternal and child health outcomes in low- and middle-income countries (LMICs).

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

We conducted a systematic review of trials published till December 2020, as per registered protocol in The International Prospective Register of Systematic Reviews (PROSPERO) (CRD42018091968). Outcomes were neonatal mortality rate (NMR), maternal mortality ratio (MMR), the incidence of low birth weight, and still birth rate (SBR). The Cochrane Pregnancy and Childbirth Group's Trials Register, Cochrane Central Register of Controlled Trials, PubMed, and Excerpta Medica Database (EMBASE) were searched. Pooled results were estimated using random-effects meta-analysis in RevMan version 5.2.

RESULTS

Twenty-five trials met the inclusion criteria. HVs were the key intervention in 12, WGMs in 11, and both interventions in 2 trials. The pooled estimates have shown that NMR was significantly reduced by HVs (OR 0.77, confidence interval [CI]: 0.67-0.90, P = 0.0007, I² = 77%) and WGMs (OR 0.76, CI: 0.65-0.90, P = 0.001, I² = 71%). SBR was significantly reduced by HVs (OR 0.77, CI: 0.70-0.85; P < 0.001, I² = 0%). Subgroup analysis of studies in which more than 10% of pregnant women participated in the WGMs showed significant reduction in NMR (OR 0.67, CI 0.58-0.77, P = 0.00001, I² = 31%) and MMR (OR 0.55, CI 0.36-0.84, P = 0.005, I² = 27%). Two studies reported improvement in birth weight by HVs.

CONCLUSIONS

HVs and WGMs (with >10% pregnant women) by paramedical professionals are effective strategies in reducing the NMR and MMR in LMICs. HVs were also effective in reducing SBR.

LDL cholesterol an unmet target in diabetic, hypertensive population pan India exposing susceptive cardiovascular disorder risk

Funding Acknowledgements

Type of funding sources: None.

Background

Management and pathophysiology of diabetes and hypertension has always been the centre of research, with new insights being found consistently. CVD is the major cause of mortality in patients with type 2 diabetes and affects approximately 32.2% of people with type 2 diabetes. Southeast Asia stands out with a higher prevalence of CAD (29.4%) compared with other regions.

Purpose

The purpose of this EHR based real world study was to identify the proportion of patients with LDL-C out of control in people living with diabetes and hypertension who were under regular care of physicians. Specialized clinical care by super-specialists ensures management of specific disorders, yet risk factors for overall cardiovascular health continue to be expressed uncontrolled.

Methods

Patients reporting for routine care in 14 centers across the country were eligible to participate in the study. Patient recruitment at each site required informed consent signature, history of at least 6 months of diabetes mellitus type 2, was sequential and independent of other sites. An EMR (Medeva) integrated research proforma was created only for this study which collected data on medical history, comorbidities, diabetic complications, medications and laboratory values of relevance to the study. The recruitment started in March 2022 and ended in August 2022 (6 months).

Results

Average age of these patients was 54.36 years, and 1238 were male and 964 were female patients. Out of this sample, 1388 patients were only diabetic and 814 patients had diabetes as well as hypertension. 256 patients 44.8% patients had LDL-C within acceptable limits and the remaining 51.2% had hyperdyslipidemia. Average LDL-C value for all patients was 107.07, average LDL-C levels in only diabetic patients was 116.51, and LDL in patients with diabetes and hypertension is 90.97. In diabetes only patients, 37% patients had LDL-C under control whereas in diabetes and hypertension group 58% patients had LDL-C under control.

Conclusion

Although diabetic patients are under regular clinical care, their LDL-C values were higher in 55.2% of the patients. This is an alarming signal that calls all the stakeholders - diabetologists, researchers, educators, dieticians, policymakers, government agencies and people with diabetes must contribute towards the management of lipid profile for prevention of cardiovascular events. Also, the proportion of patients with LDL-C under control is lesser in patients who are only diabetic as compared to patients who are both diabetic and hypertensive. This finding suggests that there is either lesser focus or inadequate on lipid profile of patients who are only diabetic; more holistic management is an unprecedented requirement. More research is needed in this direction to recognize the loopholes, manage them and prevent them adequately.

Awareness of lipid guideline recommendations for high-risk patients amongst primary care physicians in Canada

Background

Lipid guidelines for cardiovascular (CV) risk reduction have evolved in recent years, particularly since the introduction of PCSK9 inhibitors. In many jurisdictions, CV risk management is provided by primary care physicians (PCPs). We surveyed Canadian PCPs regarding their awareness and implementation of the 2021 Canadian Cardiovascular Society (CCS) lipid guideline recommendations for patients following an acute coronary syndrome (ACS) or for those with diabetes but without CV disease.

Methods and results

From a national database of PCPs with interest and/or experience in CV medicine, we invited PCPs to complete a survey regarding lipid management in high-risk patients. A committee of PCPs and specialists with lipid expertise including several co-authors of the 2021 CCS lipid guidelines had designed the survey to probe awareness and practice patterns. A total of 203 PCPs from across Canada completed the survey between January and March 2022. 23.6% of respondents had previously prescribed a PCSK9 inhibitor. Almost all (96.5%) PCPs concurred that a post-ACS patient should be seen by their PCP within 4 weeks of hospital discharge (79.3% within 2 weeks). Almost half (45.3%) responded that discharge summaries provided inadequate information relevant for PCPs, and 43% felt that lipid management post-ACS was the primary responsibility of specialists. More than half (56%) articulated challenges when seeing a post-ACS patient, related to inadequate discharge information, complexities of polypharmacy and duration of therapies, and managing perceived or real statin intolerance. 62% correctly identified the LDL-C intensification threshold of 1.8 mmol/L in post-ACS patients, while 79% considered that PCSK9 inhibitors were indicated only for those patients who were already receiving statins plus ezetimibe or had substantially elevated LDL-C levels. 55.2% were able to correctly identify clinical features associated with greatest absolute benefit of PCSK9 inhibitors in post-ACS patients. For patients with diabetes but without ASCVD, 80% of PCPs incorrectly believed that PCSK9 inhibitors were indicated for LDL-C levels above threshold despite statin therapy, and only 42% correctly identified the LDL-C threshold for treatment intensification of 2.0 mmol/L.

Conclusion

While PCPs are aware of the urgency regarding lipid management in post-ACS patients, many encounter challenges after hospital discharge, frequently deferring lipid management to specialists. Thus, almost one year following publication of the 2021 CCS lipid guidelines, substantial knowledge gaps remain regarding intensification thresholds and treatment options for patients post-ACS or for those with diabetes. Innovative and effective knowledge translation programs are urgently required.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Amgen Canada

Impact of tele rehabilitation on clinical outcomes in patients recovering from COVID-19: a preliminary investigation

Pulmonary rehabilitation has proven to be an effective therapeutic intervention for people with chronic respiratory disease. Considering the highly contagious nature of coronavirus disease (COVID-19), it becomes imperative to develop a method which can effectively improve clinical disease outcomes of these patients without any physical contact. The purpose of the study was to investigate the impact of tele rehabilitation on dyspnoea, endurance and quality-of-life in patients recovering from COVID 19. Thirty-two participants (age: 42.5±13.94, height: 165.8±10.06, weight: 68.5±9.63, body mass index: 25.0±3.61) who are recovering from COVID-19 were recruited as per the eligibility criteria. They were randomly allocated into two groups, Tele rehabilitation (n=16) and Control (n=16) by lottery method. All the selected participants were assessed at baseline for perceived dyspnoea, endurance and quality-of-life. Patients in the Tele rehabilitation group received 14 sessions of rehabilitation on alternate days online via google meet over a period of 28 days. Control group received usual care during the study period. Standard statistical tests were employed to test the study hypothesis. Results suggested a significant improvement in both dyspnoea (P=0.001) and endurance (P<0.001) in response to tele rehabilitation. Domains of quality-of-life such as physical role (P=0.02), vitality (P=0.04), emotional role (P=0.03), mental health (P=0.02) and physical components score (P=0.007) also showed significant improvement with tele rehabilitation in patients recovering from COVID-19. Findings of this preliminary study concludes that tele rehabilitation may be considered a treatment of choice in patients recovering from COVID-19 for improving outcomes of dyspnoea, endurance and quality-of-life.

Interface morphology driven exchange interaction and magnetization reversal in a Gd/Co multilayer

Rare-earth (RE)/transition metal (TM) ferromagnetic heterostructures with competing interfacial coupling and Zeeman energy provide a rich ground to study different phase states as a function of magnetic field and temperature. The interface morphology as a knob in these RE/TM heterostructures provides an excellent opportunity to engineer the macroscopic magnetic response by tuning the interface dependent microscopic interactions between the layers. We have investigated the interface morphology driven structure and magnetic properties of a Gd/Co multilayer. The interface morphology of the multilayer was controlled by annealing the multilayer at a relatively low temperature of 573 K under vacuum conditions. Combining the different experimental techniques and a simple one-dimensional spin-based model calculation, we studied the detailed magnetic structure and magnetization reversal mechanism in this system across compensation temperature (T_comp), which suggested a strong interface dependent coupling in the system. We showed that changes in the interface morphology of the Gd/Co multilayer strongly influence the macroscopic magnetic properties of the system. The calculation also confirms the formation of a helical magnetic structure with a 2π domain wall in this system below T_comp. The experimental finding and the simulation of this technologically important system will help to understand the physics of all-optical switching and related applications.

Optimization of a Flat Die Including Elongational Viscosity Effects

A software package for optimization of polymer extrusion dies is developed. Die geometry is optimized such that a uniform velocity distribution is obtained at the die exit without excessively increasing the pressure drop in the die. The software uses the BFGS optimization algorithm, and employs the adjoint method to obtain the design sensitivities. The optimization software is successfully used to optimize the geometry of a flat die for polymer sheet extrusion such that a uniform velocity distribution is obtained at the die exit, without increasing the pressure drop in the die.

A134 UES MANOMETRIC PARAMETERS IN ESOPHAGEAL MOTILITY DISORDERS

Background

Upper esophageal sphincter (UES) function may be evaluated manometrically using a solid-state high-resolution manometry (HRM) system, which allows for the measurement of manometric parameters specific to the UES. While many of these parameters have yet to be validated for use in clinical practice, there is some suggestion that there may be an association between esophageal motility and UES function.

Aims

We aimed to identify the relationship between UES manometric variables and high-resolution esophageal manometry (HREM) diagnoses.

Methods

A retrospective analysis of HREM studies was performed between 2019 and 2021. Extraction of esophageal and UES manometric variables were performed. UES manometric values of interest included: mean basal pressure (mmHg), mean residual pressure (mmHg), relaxation time-to-nadir (ms), relaxation duration (ms), and recovery time (ms). Relationships between manometric diagnosis (Chicago Classification version 3) and UES manometric variables were explored. All values are expressed a medians and group means were compared with the non-parametric Mann-Whitney U test.

Results

2119 symptomatic patients underwent HREM over the study period. Manometric diagnoses were achalasia (72 patients), esophagogastric junction outflow obstruction (286), absent contractility (108), distal esophageal spasm (53), jackhammer esophagus (32), and ineffective esophageal motility (694). 886 patients had no specific motility disorder; 643 of whom had ≤ 20% ineffective swallows and were considered symptomatic controls.

Patients with achalasia had significantly higher mean basal pressures (63.2 vs. 54.4, p = .001), mean residual pressure (3.8 vs. -1.9, p < .001), relaxation-time-to-nadir (182.0 vs. 142.0, p = .005), relaxation duration (820.5 vs. 708.0, p < .001) and recovery time (623.0 vs. 562, p < .001) compared to control patients. Among patients with achalasia, the presence of panesophageal pressurization correlated weakly with recovery time (R² .3, p = .03). Patients with ineffective esophageal motility had significantly higher mean basal pressures (61.7 vs. 54.0, p < .001).

Among all patients, patients with incomplete bolus clearance (≥ 30%) had significantly higher UES mean basal pressure (58.9 vs. 54.6, p = .004), mean residual pressure (-.62 vs. -2, p < .001), relaxation duration (724.0 vs. 707.0, p = .014) and recovery time (580 vs. 558.0, p < .001).

Conclusions

Patients with achalasia may have higher basal and residual UES pressures, and slower relaxation compared to patients with normal esophageal motility. This may reflect dynamic changes of the UES in response to obstruction at the esophagogastric junction. Elevated UES pressures are also seen in patients with ineffective esophageal motility, potentially reflecting a response to poor bolus clearance. More work needs to be done to validate these parameters in clinical practice.

Funding Agencies

None

Subclinical left and right ventricular dysfunction in COVID-19 recovered patients using speckle tracking echocardiography

Funding Acknowledgements

Type of funding sources: None.

Introduction

Myocardial injury during acute COVID-19 infection is well characterised however, its persistence during recovery is unclear.

Purpose

We assessed left ventricle (LV) global longitudinal strain (GLS) and right ventricular (RV) free wall longitudinal strain and RV global longitudinal strain (RV-GLS) using speckle tracking echocardiography (STE) in COVID-19 recovered patients (30-45 days post recovery) and studied its correlation with various parameters.

Methods

Of the 245 subjects screened, a total of 53 subjects recovered from COVID-19 infection and normal LV ejection fraction were enrolled. Routine blood investigations, inflammatory markers (on admission) and comprehensive echocardiography including STE were done for all.

Results

All the 53 subjects were symptomatic during COVID-19 illness and were categorized as mild: 27 (50.9%), moderate: 20 (37.7%) and severe: 6 (11.4%) COVID-19 illness. Reduced LV GLS was reported in 22 (41.5%), reduced RV-GLS in 23 (43.4%) and reduced RVFWS in 22 (41.5%) patients respectively. LVGLS was significantly lower in patients recovered from severe illness (mild: -20.3 ± 1.7%; moderate: -15.3 ± 3.4%; severe: -10.7 ± 5.1%; P < 0.0001). Similarly, RVGLS (mild: -21.8 ± 2.8%; moderate: -16.8 ± 4.8%; severe: -9.7 ± 4.6%; P < 0.0001) and RVFWS (mild: -23.0 ± 4.1%; moderate: -18.1 ± 5.5%; severe: -9.3 ± 4.4%; P < 0.0001) were significantly lower in subjects with severe COVID-19. Subjects with reduced LVGLS as well as RVGLS and RVFWS had significantly higher interleukin-6, C-reactive protein, lactate dehydrogenase and serum ferritin levels during index admission.

Conclusions

Subclinical LV and RV dysfunction was seen in majority of  COVID-19 recovered patients. Patients with severe disease during index admission had far lower LV and RVGLS as compared to mild and moderate cases. Our study highlights the need for close follow-up of COVID-19 recovered subjects in order to determine the long-term cardiovascular outcomes.

Asymptomatic infection and transmission of COVID-19 among clusters: systematic review and meta-analysis

OBJECTIVES

Countries throughout the world are experiencing COVID-19 viral load in their populations, leading to potential transmission and infectivity of asymptomatic COVID-19 cases. The current systematic review and meta-analysis aims to investigate the role of asymptomatic infection and transmission reported in family clusters, adults, children and health care workers, globally.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

An online literature search of PubMed, Google Scholar, medRixv and BioRixv was performed using standard Boolean operators and included studies published up to 17 August 2021. For the systematic review, case reports, short communications and retrospective studies were included to ensure sufficient asymptomatic COVID-19 transmission data were reported. For the quantitative synthesis (meta-analysis), participant data from a collection of cohort studies focusing on groups of familial clusters, adults, children and health care workers were included. Inconsistency among studies was assessed using I² statistics. The data synthesis was computed using the STATA 16.0 software.

RESULTS

This study showed asymptomatic transmission among familial clusters, adults, children and health care workers of 15.72%, 29.48%, 24.09% and 0%, respectively. Overall, asymptomatic transmission was 24.51% (95% confidence interval [CI]: 14.38, 36.02) among all studied population groups, with a heterogeneity of I² = 95.30% (P < 0.001). No heterogeneity was seen in the population subgroups of children and health care workers. The risk of bias in all included studies was assessed using the Newcastle Ottawa Scale.

CONCLUSIONS

For minimising the spread of COVID-19 within the community, this study found that following the screening of asymptomatic cases and their close contacts for chest CT scan (for symptomatic patients), even after negative nucleic acid testing, it is essential to perform a rigorous epidemiological history, early isolation, social distancing and an increased quarantine period (a minimum of 14-28 days). This systematic review and meta-analysis supports the notion of asymptomatic COVID-19 infection and person-to-person transmission and suggests that this is dependent on the varying viral incubation period among individuals. Children, especially those of school age (i.e. <18 years), need to be monitored carefully and follow mitigation strategies (e.g. social distancing, hand hygiene, wearing face masks) to prevent asymptomatic community transmission of COVID-19.

SMARCA4 inactivation promotes lineage-specific transformation and early metastatic features in the lung

SMARCA4/BRG1 encodes for one of two mutually exclusive ATPases present in mammalian SWI/SNF chromatin remodeling complexes and is frequently mutated in human lung adenocarcinoma. However, the functional consequences of SMARCA4 mutation on tumor initiation, progression, and chromatin regulation in lung cancer remain poorly understood. Here, we demonstrate that loss of Smarca4 sensitizes CCSP+ cells within the lung in a cell-type dependent fashion to malignant transformation and tumor progression, resulting in highly advanced dedifferentiated tumors and increased metastatic incidence. Consistent with these phenotypes, Smarca4-deficient primary tumors lack lung lineage transcription factor activities and resemble a metastatic cell state. Mechanistically, we show that Smarca4 loss impairs the function of all three classes of SWI/SNF complexes, resulting in decreased chromatin accessibility at lung lineage motifs and ultimately accelerating tumor progression. Thus, we propose that the SWI/SNF complex - via Smarca4 - acts as a gatekeeper for lineage-specific cellular transformation and metastasis during lung cancer evolution.

Role of α- and β-adrenergic signaling in phenotypic targeting: significance in benign and malignant urologic disease

The urinary tract is highly innervated by autonomic nerves which are essential in urinary tract development, the production of growth factors, and the control of homeostasis. These neural signals may become dysregulated in several genitourinary (GU) disease states, both benign and malignant. Accordingly, the autonomic nervous system is a therapeutic target for several genitourinary pathologies including cancer, voiding dysfunction, and obstructing nephrolithiasis. Adrenergic receptors (adrenoceptors) are G-Protein coupled-receptors that are distributed throughout the body. The major function of α1-adrenoceptors is signaling smooth muscle contractions through GPCR and intracellular calcium influx. Pharmacologic intervention of α-and β-adrenoceptors is routinely and successfully implemented in the treatment of benign urologic illnesses, through the use of α-adrenoceptor antagonists. Furthermore, cell-based evidence recently established the antitumor effect of α1-adrenoceptor antagonists in prostate, bladder and renal tumors by reducing neovascularity and impairing growth within the tumor microenvironment via regulation of the phenotypic epithelial-mesenchymal transition (EMT). There has been a significant focus on repurposing the routinely used, Food and Drug Administration-approved α1-adrenoceptor antagonists to inhibit GU tumor growth and angiogenesis in patients with advanced prostate, bladder, and renal cancer. In this review we discuss the current evidence on (a) the signaling events of the autonomic nervous system mediated by its cognate α- and β-adrenoceptors in regulating the phenotypic landscape (EMT) of genitourinary organs; and (b) the therapeutic significance of targeting this signaling pathway in benign and malignant urologic disease. Video abstract.

Integrin-mediated interactions with a laminin-presenting substrate modulate biosynthesis and phenotypic expression for cells of the human nucleus pulposus

With aging and pathology, cells of the nucleus pulposus (NP) de-differentiate towards a fibroblast-like phenotype, a change that contributes to degeneration of the intervertebral disc (IVD). Laminin isoforms are a component of the NP extracellular matrix during development but largely disappear in the adult NP tissue. Exposing human adult NP cells to hydrogels made from PEGylated-laminin-111 (PEGLM) has been shown to regulate NP cell behaviors and promote cells to assume a biosynthetically active state with gene/protein expression and morphology consistent with those observed in juvenile NP cells. However, the mechanism regulating this effect has remained unknown. In the present study, the integrin subunits that promote adult degenerative NP cell interactions with laminin-111 are identified by performing integrin blocking studies along with assays of intracellular signaling and cell phenotype. The findings indicate that integrin α3 is a primary regulator of cell attachment to laminin and is associated with phosphorylation of signaling molecules downstream of integrin engagement (ERK 1/2 and GSK3β). Sustained effects of blocking integrin α3 were also demonstrated including decreased expression of phenotypic markers, reduced biosynthesis, and altered cytoskeletal organization. Furthermore, blocking both integrin α3 and additional integrin subunits elicited changes in cell clustering, but did not alter the phenotype of single cells. These findings reveal that integrin- mediated interactions through integrin α3 are critical in the process by which NP cells sense and alter phenotype in response to culture upon laminin and further suggest that targeting integrin α3 has potential for reversing or slowing degenerative changes to the NP cell.

Novel deep transfer learning model for COVID-19 patient detection using X-ray chest images

Around the world, more than 250 countries are affected by the COVID-19 pandemic, which is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This outbreak can be controlled only by the diagnosis of the COVID-19 infection in early stages. It is found that the radiographic images are ideal for the fastest diagnosis of COVID-19 infection. This paper proposes an ensemble model which detects the COVID-19 infection in the early stage with the use of chest X-ray images. The transfer learning enables to reuse the pretrained models. The ensemble learning integrates various transfer learning models, i.e., EfficientNet, GoogLeNet, and XceptionNet, to design the proposed model. These models can categorize patients as COVID-19 (+), pneumonia (+), tuberculosis (+), or healthy. The proposed model enhances the classifier's generalization ability for both binary and multiclass COVID-19 datasets. Two popular datasets are used to evaluate the performance of the proposed ensemble model. The comparative analysis validates that the proposed model outperforms the state-of-art models in terms of various performance metrics.

Transcriptional and translational abundance of visfatin (NAMPT) in buffalo ovary during estrous cycle and its in vitro effect on steroidogenesis

Visfatin is a highly conserved adipokine protein having multiple biological effects, including regulation of reproduction. Evidence in recent years has shown a pivotal role of visfatin in ovarian functions. The present study was conducted to evaluate the mRNA and protein abundance of visfatin in ovarian follicles and corpora lutea (CL) during different stages of their development in the ovary of water buffalo (Bubalus bubalis) and to investigate the role of visfatin on estradiol (E₂) and progesterone (P₄) secretion. Ovarian follicles were categorized in to small (F1), medium (F2), large (F3), and preovulatory (F4) follicles, whereas the CL were categorized into early (CL1), mid (CL2), late (CL3), and regressing (CL4) CL stage. In follicles, the mRNA and protein abundance of visfatin increased with an increase in follicle size in granulosa cells (GCs) and theca interna (TI) cells. In CL, the transcript of visfatin was significantly (P < 0.05) higher in the late luteal phase (CL3) than that in other phases. The translational abundance of visfatin was significantly higher in the mid and late luteal phase. Visfatin was localized in the cytoplasm of GC and TI of ovarian follicles and small and large luteal cells of CL. GCs were cultured in vitro and treated at 0, 1, and 10 ng/mL visfatin either alone or in the presence of FSH (30 ng/mL) or IGF-I (10 ng/mL) for 48 h. The luteal cells were treated with visfatin at 0, 1, and 10 ng/mL dose for 48h. There was significant (P < 0.05) increase in estradiol (E₂) secretion from GCs at 10 ng/mL dose of visfatin and visfatin (10 ng/mL) +IGF-I (10 ng/mL). Visfatin also increased (P < 0.05) progesterone (P₄) secretion from cultured luteal cells at both 1 and 10 ng/mL dose. In GCs, visfatin in the presence of IGF-I increased the transcriptional abundance of cytochrome P45019A1 (CYP19A1), the gene for key enzyme aromatase. In luteal cells, the visfatin increased mRNA abundance of factors involved in progesterone synthesis viz. steroidogenic acute regulatory protein (StAR), cytochrome P45011A1 (CYP11A1), 3beta-hydroxysteroid dehydrogenase (HSD3B1). The present study provided evidence that visfatin is expressed in ovarian follicles and CL of buffalo ovary and visfatin has a stimulatory effect on estradiol and progesterone secretion in ovarian cells of water buffalo.

Accurate Simulation of the Four Modes of Post-Die Extrudate Shape Distortion

A combined flow, thermal and structural analysis is employed to simulate post-die extrudate distortion in different profile dies. All four factors which can cause extrudate distortion, namely, nonuniform exit velocity distribution, extrudate shrinkage, extrudate draw down, and deformed shape of the calibrator or sizer profile, are simulated. To analyze the effect of exit velocity variation on extrudate distortion, the parameterized geometry of a simple profile die is optimized using an extrusion die optimization software. The simulation results presented for a bi-layer profile die successfully demonstrate how gradually changing profile shape in successive calibrators/sizers can be used to simplify the die design for extrusion of complex profiles. The predicted extrudate shape and layer structure for the bi-layer die are found to accurately match with those in the extruded product.

A139 IMPROVED QUALITY OF LIFE AFTER ENDOSCOPIC THERAPY FOR BARRETT’S ESOPHAGUS AND EARLY ESOPHAGEAL CANCER IN SOUTHERN ALBERTA

Background

In patients with Barrett’s esophagus (BE), endoscopic therapy reduces the risk of progression to invasive esophageal adenocarcinoma (EAC). Data on the impact of endoscopic therapy on patient quality of life (QoL) is limited.

Aims

We aimed to assess: (1) change in QoL during the course of endoscopic therapy for BE, (2) factors which predict this change, (3) whether achieving complete remission of dysplasia (CRD) or intestinal metaplasia (CRIM) affect the degree of change.

Methods

We conducted a retrospective observational study using a prospectively maintained database of BE patients treated in Calgary, Alberta from 2013–2020 containing data on demographics, BE disease characteristics and therapeutics, QoL, and follow-up. QoL was determined prior to initiation of therapy and after each treatment session using a validated questionnaire. Descriptive statistics were calculated and change in QoL was compared using a Wilcoxon signed ranks test. Backwards multiple linear regression analysis was performed to determine predictors of change in QoL.

Results

Of 130 BE patients, 112 (86.1%) were male and 104 (80%) had dysplastic histology or intramucosal carcinoma on index endoscopy. Mean (SD) age was 65.6 (12.0) years. At time of analysis, 76 patients (58.5%) had completed endoscopic therapy, of whom 69 (90.8%) achieved CRIM; 54 patients (41.5%) were still undergoing treatment. There was significant improvement in all QoL measures during the treatment course except for “depression” (Table 1). Patients with CRIM or CRD had reductions in “sleep difficulty” and “negative impact on life” to a significantly greater degree vs patients not achieving CRIM (Δ sleep -0.45 vs 0.0, P=0.002; Δ negative impact -0.4 vs -0.05, P=0.014) or CRD (Δ sleep -0.40 vs +0.60, P=0.002; Δ negative impact -0.40 vs +0.20, P=0.04). Multiple linear regression revealed older age (B=-0.03, P=0.008) and fewer number of EMR sessions (B=0.254, P=0.008) were correlated with greater improvement in QoL.

Conclusions

Endoscopic therapy improves QoL in BE patients, especially in those achieving CRIM/CRD. Older age and fewer EMRs are correlated with greater improvement in QoL. These results further reinforce the role of endoscopic therapy as the first line treatment of BE and early EAC.

Funding Agencies

None

A systematic review of reports of quality improvement for bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) is the most common morbidity of preterm infants, and its incidence has not responded to research and intervention efforts to the same degree as other major morbidities associated with prematurity. The complexity of neonatal respiratory care as well as persistent inter-institutional variability in BPD rates suggest that BPD may be amenable to quality improvement (QI) efforts. We present a systematic review of QI for BPD in preterm infants. We identified 22 reports from single centers and seven from collaborative efforts published over the past two decades. In almost all of the reports, respiratory QI interventions successfully reduced BPD or other key respiratory measures, particularly for infants with birth weight over 1000 g. Several themes and lessons from existing reports may help inform future efforts in both research and QI to impact the burden of BPD.