bluuebunny/crossref_metadata_2025 huggingface dataset:
A81 OPTIMIZING THE INDICATIONS FOR BILIARY STENT PLACEMENT IN PATIENTS WITH CBD STONES: A QUALITY IMPROVEMENT INITIATIVE TO ENHANCE PATIENT CARE AND REDUCE HEALTHCARE RESOURCE UTILIZATION
Authors: Alzahrani I , Alhaidari S I S , Alhanaee M , Decanini A , Mohamed M , Zepeda-Gomez S , Mathura P , Zhang J , Sandha G
Published: March 2023

Background

A retrospective chart audit was performed to review biliary stent utilization from January 2020 to 2021 at the University of Alberta Hospital (UAH). Inappropriate stent usage was identified in 16% of patients with common bile duct (CBD) stones presenting for endoscopic retrograde cholangiopancreatography (ERCP). To improve this clinical practice, a quality improvement (QI) initiative was developed and completed.

Purpose

To reduce the number of inappropriately inserted biliary stents in patients with CBD stones.

Method

The results of the chart audit (pre-intervention) were shared with the ERCP group. The QI intervention was to align biliary stent insertion in accordance with published guidelines. A chart audit (post-intervention) was then performed on all ERCPs from July, 2021 to June, 2022. The indication for biliary stent insertion was assessed independently by two blinded reviewers.

Result(s)

A total of 661 patients (337 F) with mean age of 59±19 years (range 12-98 years) underwent 885 ERCPs during this post-intervention period. Of the 661 patients, 384 (58%) were referred for CBD stones. A total of 192 biliary stents (105 plastic, 85 metal) were placed during the first ERCP (192/661, 29%), as compared to the pre-intervention year (223/598, 37%, p=ns). However, only 13/192 stents (7%) were placed not in accordance with published guidelines (kappa=0.53), compared with 63/223 (28%) in the pre-intervention year (p<0.0001). This accounts for a 75% reduction in overall unnecessary stent placement. This reduction was mainly seen in the CBD stone subgroup, where there was an 88% reduction in inappropriate biliary stent placement compared to the pre-intervention year (8/384, 2% vs. 61/376, 16%, p<0.0001).

Image

Conclusion(s)

Education to align practice in accordance with published guidelines has demonstrated a significant improvement in biliary stent insertion during ERCP in patients with CBD stones. This has resulted in significantly fewer inappropriate stent placements, a reduction in unnecessary follow-up ERCPs, and an overall saving of healthcare resources.

Please acknowledge all funding agencies by checking the applicable boxes below

None

Disclosure of Interest

None Declared
A82 PREVALENCE AND NON-INVASIVE SCREENING FOR CYSTIC FIBROSIS RELATED LIVER DISEASE IN A COHORT FOLLOWED AT A CYSTIC FIBROSIS REFERENCE CENTER
Authors: Coman D E , Vincent C , Lavoie A , Bilodeau M , Hercun J
Published: March 2023

Background

The reported prevalence of cystic fibrosis (CF) related liver disease (CFLD) varies widely based on diagnostic criteria but reaches up to 40% in some cohorts. Furthermore, its clinical impact is significant as hepatic involvement is the 3rd leading cause of mortality in CF patients and is associated with a lower life expectancy. Due to the heterogeneous clinical presentation of CFLD, clear diagnostic criteria and non-invasive assessment methods are lacking.

Purpose

This study aimed to measure the prevalence of CFLD in a cohort of patients followed at a tertiary CF center.

Method

The files of all patients followed at the CF clinic of the Centre hospitalier de l’Université de Montréal in 2021 were retrospectively reviewed. Imaging reports, histopathology, laboratory values and transient elastography results were assessed. The NIH criteria were used to define CFLD through either presence of one major criteria (abnormal imaging) or two minor criteria (persistently abnormal lab values, hepatosplenomegaly, or transient elastography ≥ 7 kPa).

Result(s)

358 patients were included in our study, 56% male with a median age of 36 years. While mean liver tests were within normal limits (ALT 24 U/L, AST 26 U/L, ALP 96 U/L, GGT 29 U/L), 182 patients (51%) had at least one episode of abnormal liver function tests (LFTs), and 85 patients (24%) had persistently abnormal LFTs. CFLD was present in 42 patients (12%), with 39 patients presenting major criteria and 3 patients presenting minor criteria. In addition, 67 patients (19%) had solely hepatic steatosis. Furthermore, clinically significant portal hypertension and esophageal varices were detected in 50% of patients with CFLD who underwent upper endoscopy (n=20). Median transient elastography value was 5.4 kPa (interquartile range 4.25 kPa) in the 51 patients with exam results, and 32% had values ≥ 7 kPa. Fibroscan values correlated well with the presence of major criteria, with an area under the curve (AUROC) of 0.80 (0.68-0.92, p=0.0007), while non-invasive serological markers did not perform as well (Fib4: AUROC 0.70 (0.59-0.81) and APRI: AUROC 0.69 (0.59-0.80)).

Conclusion(s)

The overall prevalence of CFLD, including hepatic steatosis, was 31% in this cohort. Prompt recognition is important in clinical care in order to prevent hepatic complications from cirrhosis and portal hypertension. The use of Fibroscan seems promising for detecting CFLD.

Please acknowledge all funding agencies by checking the applicable boxes below

None

Disclosure of Interest

None Declared
A84 FACTORS ASSOCIATED WITH HIGH LEVELS OF TELEPHONE CARE SATISFACTION AMONG INDIVIDUALS WITH INFLAMMATORY BOWEL DISEASE
Authors: Foncham J N , Rohatinsky N , Fowler S , Peña-Sánchez J N
Published: March 2023

Background

Individuals with inflammatory bowel disease (IBD) require regular medical follow-up with gastroenterology care providers. Individuals in rural areas face barriers in assessing specialized IBD care. Virtual care (VC) may act as a solution. The coronavirus disease 2019 pandemic increased the use of VC, particularly telephone care (TC) appointments in Saskatchewan, Canada. There is limited evidence around the levels and factors associated with satisfaction with TC among individuals with IBD.

Purpose

This study aims to measure satisfaction with TC in individuals with IBD who live in Saskatchewan, Canada, and evaluate the factors associated with TC satisfaction.

Method

A cross-sectional study was conducted among individuals with IBD through an online survey between December 2021 and April 2022 in Saskatchewan. The Telephone Care Satisfaction Questionnaire for individuals with IBD (TCSQ-patient) was a 16-item questionnaire used to measure TC satisfaction on a scale from 1 (very dissatisfied) to 7 (very satisfied). The online survey also included the Quality of Care Through the Patient’s Eyes-IBD (QUOTE-IBD) questionnaire, Short Inflammatory bowel disease questionnaire (SIBDQ), and demographic questions. Factors associated with TC satisfaction were explored using linear regression models. A backward model building strategy was used, and 95% confidence intervals (95%CI) were reported.

Result(s)

In total, 87 individuals with IBD participated in the study. Among the study participants, 54 (64.3%) had Crohn's disease, 53 (61.6%) were female, 60 (69.8%) lived in urban centres, and 37 (43.5%) were between 41-59 years old. The mean satisfaction with TC was 5.70 (SD=0.94). In addition, the means of the QUOTE-IBD and SIBDQ were, respectively, 8.96 (SD=1.70) and 48.14 (SD=13.02). In the bivariate analysis, area of residence (rural vs. urban) and health related quality of life quality (SIBDQ>50 vs SIBDQ<50) were associated with satisfaction with TC, respectively, 0.47 (95%CI 0.02-0.91) and 0.48 (95%CI 0.08-0.88). Adjusting by gender, age group, type of disease, and health care provider managing IBD, we identified that the satisfaction with TC was 0.48 (95%CI 0.02-0.94) higher among individuals with IBD living in rural Saskatchewan in comparison to their urban counterparts.

Conclusion(s)

Individuals living with IBD in Saskatchewan reported high levels of satisfaction with TC. Rural residence is associated with higher levels of TC satisfaction. These results could help in the promotion of TC utilization and improve access to specialized IBD care, especially among those living in rural areas.

Please acknowledge all funding agencies by checking the applicable boxes below

Other

Please indicate your source of funding;

Saskatchewan Health Research Foundation (SHRF)

Disclosure of Interest

None Declared
A97 LARGE NON-PEDUNCULATED COLONIC POLYP (LNPCP) OUTCOMES REFERRED FOR ENDOSCOPIC RESECTION IN BRITISH COLUMBIA: A QUALITY ASSURANCE INITIATIVE
Authors: Tam L , Akhtar D , Hill E , Jiang S , Ghuman A , Xiong W , Shahidi N
Published: March 2023

Background

Endoscopic resection techniques have become the primary treatment strategy for the vast majority of large (≥ 20mm) non-pedunculated colonic polyps (LNPCPs). Despite this, surgery is still commonly performed with evidence suggesting an increasing trend over time. There is limited Canadian data confirming the effectiveness and safety of an endoscopic management strategy for LNPCPs.

Purpose

To investigate clinical outcomes of patients referred for endoscopic management of a LNPCP.

Method

Retrospective single-centre analysis of patients referred to a single endoscopist for the management of LNPCPs within a tertiary referral practice. LNPCPs were further subdivided into non-complicated (NC-LNPCP) or complicated (C-LNPCP) defined as those involving the ileocecal valve, appendiceal orifice, circumferential or previously attempted. Performance outcomes were evaluated by the frequencies of technical success (removal of all polypoid tissue during index procedure) and need for colorectal surgery. Safety was evaluated by the frequencies of clinically significant intraprocedural bleeding (CSIPB), clinically significant post-endoscopic resection bleeding (CSPEB), intra-procedural perforation and delayed perforation. Recurrence (either endoscopic or histologic) was evaluated at first surveillance colonoscopy (SC1). Continuous variables were summarized using median (IQR). Categorical variables were summarized as frequencies (%). To test for association between categorical variables, the Pearson χ2 or the Fisher exact test were used, where appropriate. For continuous variables, the Mann-Whitney U test was used. A probability (p) value of <0.05 was considered statistically significant.

Result(s)

Between January 2021 to March 2022, 263 LNPCP were referred for endoscopic resection and 41 LNPCP were excluded (23 pedunculated, 14 optical evaluation suggestive of deeply invasive cancer, 4 other). 222 LNPCP (188 NC-LNPCP, 34 C-LNPCP) underwent endoscopic resection. Median size was 25mm (IQR 20-30mm) with the majority undergoing cold snare resection (115, 51.8%). Polyposis (Adenomatous or serrated) was present in 23 (12.6%) cases respectively. Technical success was 97.3%. Cancer was present in 5 (2%). Clinically significant bleeding (CSPEB) occurred in 2.7%, DMI IV in 1.8% and there were no delayed perforations. Recurrence occurred in 4 (3.5%) at SC1 and 11 (5%) required surgery due to technical failure, submucosal invasion on pathology and clinically significant bleeding.

Image

Conclusion(s)

Endoscopic resection as the primary treatment strategy for LNPCPs offers a safe and effective alternative to surgery in British Columbia.

Please acknowledge all funding agencies by checking the applicable boxes below

None

Disclosure of Interest

None Declared
A138 SERRATED POLYPOSIS SYNDROME IN INFLAMMATORY BOWEL DISEASE: A SEQUELAE OF CHRONIC DISEASE ACTIVITY OR NEW WHO PHENOTYPE?
Authors: Jiang S X , Xiong W , Shahidi N
Published: March 2023

Background

Serrated polyposis syndrome (SPS) is a growing health concern with up to 1 in 125 universal screening program participants meeting diagnostic criteria. Conversely, SPS in inflammatory bowel disease (IBD) is rarely described in the literature, despite the predisposition for serrated epithelial change and serrated polyps in this population.

Purpose

To describe a case of World Health Organization (WHO) criterion I SPS in a patient with IBD, and discuss the existing literature on this rare occurrence.

Method

Case report and review of the literature.

Result(s)

Case Report

A 53-year-old female with ulcerative colitis (UC; Phenotype: Left-sided; Duration of disease: 40 years; Medical therapy: sulfasalazine) undergoing regular endoscopic surveillance was recently found to have multiple serrated-class lesions including 6 in the sigmoid colon ranging between 8-30mm in size; this included 3 sessile serrated lesions (SSLs) between 20-30mm removed by piecemeal cold snare resection without complication and 2 residual large SSLs for staged endoscopic resection. No endoscopic disease activity was appreciated (Mayo 0), with histopathology of the sigmoid colon and rectum demonstrating chronic inactive colitis.

Literature Review

From 2008 to 2021, there are eleven reported cases of SPS in IBD. Six patients had UC and most were in remission for several decades at the time of SPS diagnosis. Most SPS cases met WHO criteria and fit within described phenotypes. While the case above meets WHO criterion I for SPS, the presence of large distal lesions is atypical, raising the question of whether chronic disease activity contributed to the development of these serrated lesions, given the known predisposition for serrated epithelial change and serrated lesions in patients with colonic IBD.

Image

Conclusion(s)

SPS in patients with IBD is rare. Questions remain about the role of chronic disease activity contributing to the formation of serrated lesions, its clinical relevance, and optimal management strategy.

Please acknowledge all funding agencies by checking the applicable boxes below

None

Disclosure of Interest

None Declared
A140 ECTOPIC SPLEEN PRESENTING AS A GASTRIC SUBMUCOSAL LESION
Authors: Balubaid I , Almudaires A , Sey M
Published: March 2023

Background

Accessory spleen is ectopic splenic tissue which can be either congenital or acquired. It is usually an asymptomatic incidental finding. In the context of known malignancy, accessory spleen can be mistaken for metastasis.

Purpose

Here, we share a case of ectopic spleen presenting as a gastric subepithelial lesion post splenectomy. Rare cases have been reported in the literature.

Method

Case Report and Literature Review

Result(s)

Case:

A middle age male with history of splenic rupture secondary to a motor vehicle accident and metastatic renal cancer was found to have a gastric subepithelial lesion on endoscopy. Endoscopic ultrasound (EUS) revealed a subepithelial mass coming off the submucosa or muscularis mucosa of the gastric wall with intact muscularis propria. EUS-guided core biopsy was performed and demonstrated splenic tissue

Conclusion(s)

Splenic tissue should be considered in the differential diagnosis when assessing gastric subepithelial tumors even in the context of previous trauma to the spleen. In addition, EUS-guided core biopsy may be required to rule out metastatic disease.

Please acknowledge all funding agencies by checking the applicable boxes below

None

Disclosure of Interest

None Declared

ESOPHAGEAL, GASTRIC & DUODENAL DISORDERS
A199 BIOFILMS IN THE APPENDIX AND OTHER NON-INFLAMED SECTIONS OF THE COLON IN PEDIATRIC PATIENTS WITH INFLAMMATORY BOWEL DISEASES
Authors: Arjomand Fard N , Bording-Jorgensen M , Webb J , Veniamin S , Cheng C , Perry T , Wine E
Published: March 2023

Background

Biofilms, aggregated bacteria colonizing the extracellular polymeric substances matrix, are associated with the mucosa of inflammatory bowel diseases (IBD) patients with some studies showing a mean density of the mucosal biofilms 2-fold higher in IBD patients than in controls. The appendix, which is a highly immune organ, seems to be involved in IBD pathogenesis.

Purpose

In this study we aimed to evaluate biofilms in the appendix and other non-inflamed regions of the colon in pediatric IBD patients. We hypothesized that biofilms composed of pathobionts in these sections could drive inflammation in IBD patients.

Method

Tissues from the appendix, peri-appendicular region, cecum, and ascending colon (ASC), collected from the resected colons of 9 pediatric IBD patients and one pediatric non-IBD patient, preserved in methanol Carnoy’s solution were processed and paraffin embedded. Combined fluorescence in situ hybridization (FISH) for biofilms (probe: EUB338) and immunofluorescence (IF) mucin staining (MUC2) identified biofilms and their location. Biofilm formation capacity of culturable bacteria (identified through 16S DNA Sanger sequencing) from these sections was measured. Interleukin (IL)-8 (pro-inflammatory chemokine) and IL-10 (anti-inflammatory cytokine) expressions were assessed by tissue qPCR.

Result(s)

FISH demonstrated biofilms in these sections, in close proximity to epithelial cells. We used a biofilm formation assay to assess the ability of the identified bacteria from these sections to form biofilms, illustrating their potential to colonize and evade host defense and potential antibiotics. We found that Enterococcus avium has a significantly higher ability to form biofilms than the negative control. IL-8 and IL-10 both had the highest expression level in the appendix and peri-appendicular region and the lowest in the ASC among all the patients, suggesting an active immune response. Mechanistic experiments are in progress to investigate the type of bacteria involved in the biofilms and their effects on the gut barrier integrity.

Conclusion(s)

Biofilms adjacent to the epithelium, especially in the appendix and peri-appendix, could interact with or invade epithelial cells. The elevated chemokine transcript level in the appendix could reflect the recruitment of immune cells to this section following bacterial invasion, resulting in the activation of the immune system. Identifying the bacteria involved in the biofilms and clarifying their characteristics will aid us in developing novel microbe-altering treatment strategies or personalized medicine.

Disclosure of Interest

None Declared
A206 SYNERGISTIC EFFECTS OF HISTAMINE AND PROTEASES IN VISCERAL HYPERSENSITIVITY
Authors: Gilmour D A , Jimenez Vargas N , Omar A , Vanner S , Lomax A , Reed D
Published: March 2023

Background

Irritable bowel syndrome (IBS) is characterized by chronic abdominal pain. Previous work has shown IBS fecal supernatants (FS) increase the excitability of nociceptive neurons compared to healthy volunteer FS. Altered production of intestinal mediators, including elevated histamine content and proteolytic activity, have been implicated in these effects. We hypothesized that the effects of histamine and proteases on neuronal excitability may be synergistic.

Purpose

1) Determine whether the excitatory effect of IBS patient FS can be abolished by histamine receptor antagonists and protease inhibitors. 2) Investigate whether the excitatory effects of histamine and proteases potentiate each other’s effects on visceral nociception

Method

Extracellular recordings were performed, measuring action potentials from mechanosensitive extrinsic afferent nerves innervating the mouse colon during colonic distensions to 60 mmHg. Colons were perfused (20 minutes) with histamine receptor antagonists (1 µM pyrilamine, 10 µM ranitidine, 30 nM clobenpropit, 1 µM JNJ7777120) or protease inhibitors (10 µM EDTA, 0.2 µM bestatin, 0.03 µM Pepstatin A, 0.03 µM E-64) prior to treatment with the IBS patient FS. Perforated patch clamp experiments were used to measure neuronal excitability from mouse dorsal root ganglion neurons by recording rheobase (minimum current required to elicit an action potential fire). This technique was used to examine the effect of subthreshold concentrations of histamine (1µM) and trypsin (5nM), as well as their simultaneous administration on the neurons.

Result(s)

Luminal administration of histamine antagonists or protease inhibitors blocked the excitatory effect of the IBS patient FS (two-way ANOVA P=0.44 for protease antagonists, two-way ANOVA P=0.37 for histamine antagonists). Patch clamp experiments revealed that a subthreshold concentration of either histamine (1µM) or trypsin (5nM) had no effect on neuronal rheobase, whereas the combination significantly decreased neuronal rheobase (one-way ANOVA with Tukey’s test, P=0.006).

Image

Conclusion(s)

These findings demonstrate that either histamine receptor antagonists or protease inhibitors inhibit the excitatory effect of IBS patient FS and suggest that a potentiating effect exists between the actions of histamine and proteases on nociceptive neurons.

Disclosure of Interest

None Declared
A207 CLONAL PATTERNS BETWEEN POUCH NEOPLASIA AND PRIOR COLORECTAL NEOPLASIA IN INFLAMMATORY BOWEL DISEASE PATIENTS: AN EXPLORATORY COHORT STUDY
Authors: Van Lierop L , te Groen M , Derikx L , Ylstra B , Hoentjen F , Nagtegaal I , Doubrava-Simmer F
Published: March 2023

Background

Inflammatory bowel disease (IBD) patients with an ileo-anal pouch anastomosis (IPAA) bear an increased risk of pouch neoplasia, with prior colorectal neoplasia as the strongest predictor. It is unknown if pouch neoplasia develops independently or is derived from prior colorectal neoplasia.

Purpose

We aimed to assess potential clonality between prior colorectal neoplasia and pouch neoplasia in IPAA patients with IBD.

Method

In this explorative study we used the Dutch Nationwide Pathology Databank to identify IBD patients with both pouch neoplasia and colorectal neoplasia prior to colectomy. Clonality was assessed on colonic tissue of the lesion with shallow whole genome sequencing based copy number aberration (CNA) analysis and validated with immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH).

Result(s)

We included 13 patients who fulfilled the inclusion criteria. Three patients showed matching clonality CNA profiles between prior colorectal neoplasia and pouch neoplasia, validated with matching IHC and FISH for p19 and HER2. Patients with matching clonal samples also showed on retrospective review concordant histology of the neoplastic lesion pre- and post IPAA, positive resection margins, metastasized disease or a short interval (<2 years) between colorectal and pouch neoplasia diagnoses.

Image

Conclusion(s)

Three patients showed matching clonality patterns of neoplastic lesions, confirmed by clinical and histological data. Most pouch neoplasia in our cohort were molecularly different from their prior colorectal neoplasia. CNA provides a feasible method for clonality assessment in patients with colorectal neoplasia and subsequent pouch neoplasia.

Disclosure of Interest

None Declared
A220 ONTARIO POPULATION TRENDS IN INTESTINAL AND EXTRA-INTESTINAL CANCERS OVER 25 YEARS AMONG PERSONS WITH INFLAMMATORY BOWEL DISEASES AND MATCHED CONTROLS
Authors: Murthy S K , Kaplan G G , Coward S , Kuenzig E , Benchimol E I , Zubieta A , Otley A , Bitton A , Bernstein C N , Targownik L , Jones J , Begum J , Pugliese M , Singh H
Published: March 2023

NOT PUBLISHED AT AUTHOR’S REQUEST

Please acknowledge all funding agencies by checking the applicable boxes below

CCC, CIHR

Disclosure of Interest

S. Murthy: None Declared, G. Kaplan Grant / Research support from: Ferring, Janssen, AbbVie, GlaxoSmith Kline, Merck, and Shire, Consultant of: AbbVie, Janssen, Pfizer, Amgen, Takeda, Gilead, Speakers bureau of: AbbVie, Janssen, Pfizer, Amgen, and Takeda, S. Coward: None Declared, E. Kuenzig: None Declared, E. Benchimol Consultant of: Hoffman La-Roche Limited, Peabody & Arnold LLP, McKesson Canada, Dairy Farmers of Ontario for matters unrelated to medications used to treat inflammatory bowel disease., A. Zubieta: None Declared, A. Otley: None Declared, A. Bitton: None Declared, C. Bernstein Grant / Research support from: Abbvie Canada, Janssen Canada, Pfizer Canada, Bristol Myers Squibb Canada, Takeda Canada; Amgen Canada, Sandoz Canada , Consultant of: Abbvie Canada, Amgen Canada, Bristol Myers Squibb Canada, JAMP Pharmaceuticals, Janssen Canada, Pfizer Canada, Sandoz Canada, Takeda, Speakers bureau of: Abbvie Canada, Janssen Canada, Pfizer Canada and Takeda Canada, L. Targownik Grant / Research support from: Janssen Canada, Consultant of: AbbVie Canada, Takeda Canada, Merck Canada, Pfizer Canada, Janssen Canada, Roche Canada, and Sandoz Canada, J. Jones Consultant of: Janssen, Abbvie, Pfizer, Takeda, Speakers bureau of: Janssen, Abbvie, Pfizer, Takeda, J. Begum: None Declared, M. Pugliese: None Declared, H. Singh Consultant of: Pendopharm, Amgen Canada, Bristol Myers Squibb Canada, Roche Canada, Sandoz Canada, Takeda Canada, and Guardant Health, Inc.,
A267 IDENTIFYING ENTEROBACTERIACEAE VIRULENCE GENES ASSOCIATED WITH ACTIVE DISEASE IN ULCERATIVE COLITIS PATIENTS USING CULTURE-DEPENDENT AND -INDEPENDENT APPROACHES
Authors: Tertigas D , Rinawi F , Griffiths A , Surette M
Published: March 2023

Background

The prevalence of inflammatory bowel disease (IBD) in Canada is among the highest in the world and is estimated to affect 1 in 100 Canadians by 2030. Ulcerative colitis (UC) is a type of IBD characterized by mucosal inflammation of the large intestine. UC is believed to arise through a complex interplay of the host immune responses and changes in the gut microbiota in a genetically susceptible individual. Therapies targeting the gut microbiota, such as antibiotics and fecal microbiota transplantation (FMT), have been effective in treating UC, suggesting infectious triggers should be explored.

Purpose

Some data suggests the development of UC can be driven by pathogenic bacteria of the family Enterobacteriaceae, which can carry virulence genes important for colonizing the gut (e.g. fimH) and disrupting the intestinal epithelium (e.g. hylA). However, many studies have focused on a single species (e.g. Escherichia coli) and thereby underestimate the importance of these virulence genes that are shared across the Enterobacteriaceae family. I aim to investigate whether specific virulence genes contribute to disease activity in some patients with UC and to show that these virulence genes are carried by strains of many Enterobacteriaceae species.

Method

UC patient stool samples were collected throughout enrolment in randomized control trials of FMT for adult UC and microbiome studies in early-onset pediatric UC. The stool samples were cultured on MacConkey agar to enrich for Enterobacteriaceae. Samples from before and after treatment were sent for targetted cultured-enriched metagenomic sequencing and strains were isolated from baseline samples only for whole genome sequencing. The taxonomy of each genome and taxonomic composition of each metagenome were annotated along with virulence genes and antimicrobial resistance genes. Phenotypic assays of cultured isolates were used to capture diversity and virulence activity.

Result(s)

Approximately 7500 colonies from UC patient stool samples were isolated and phenotyped. Based on the initial screens, 130 isolates were selected to comprise our Enterobacteriaceae strain collection. Across all patient samples, we detected 19 different species of the Enterobacteriaceae family across six genera from the genomic and metagenomic data. We identified virulence genes found across multiple species from the Enterobacteriaceae family within genomes and metagenomes, and by performing phenotypic assays of the cultured isolates.

Conclusion(s)

Further exploration of the distribution of these virulence genes in UC patients during active disease or remission and healthy controls can provide insight into the pathogenesis of UC. Identifying infectious agents in even a subset of UC patients will allow for more targeted diagnosis and treatment approaches.

Disclosure of Interest

None Declared
A290 PHENOTYPE AND OUTCOME OF PATIENTS HOSPITALIZED FOR ACUTE PANCREATITIS IN A TERTIARY PEDIATRIC CENTER
Authors: Li T , Blain S , Korman C , David A , Mohamed M , Elhaoua D , Alvarez F , Deslandres C , Dirks M , Halac U , Grzywacz K , Lallier M , Jantchou P
Published: March 2023

Background

A recent meta-analysis of 48 studies, showed an equal prevalence of AP (16%) among the following etiologies; systemic disease, alcohol, medication, genetics, gallstones and infection in North American hospitalized and ambulatory pediatric patients. However, data on the epidemiology of severe pediatric acute pancreatitis (AP) in Canada are lacking.

Purpose

We aim to evaluate the clinical presentation, etiologies, comorbidities and outcome of pediatric patients with AP admitted to a tertiary hospital in Quebec, Canada.

Method

A retrospective observational cohort study (January 2014-December 2021) was performed at the CHU Sainte-Justine. Descriptive analyses were performed with SAS statistical softwar

Result(s)

Among the 214 patients included (110 (51%) males), 58 (27.1%) were already hospitalized at time of AP diagnosis (AP as secondary diagnosis) while 156 (72.9%) were admitted from the emergency room mainly with a presentation of abdominal pain (AP as primary diagnosis). Thirty-two patients (15.0%) were transferred to the ICU due to hemodynamic instability or respiratory failure. Comorbidities included cancer (38 patients (17.7%)), obesity (17 (7.9%)) and inflammatory bowel disease (15 (7.0%)). The three most commonly identified etiologies were medication (19.6%), biliary disease (16.3%) and infection (14,9%). Despite extensive investigations, 26.2% of cases were idiopathic. The main complications were, ascites (48 patients (22.4%)), necrotic pancreatitis (10 (4.6%)) and pancreatic pseudocyst (10 (4.6%)). The median duration of hospitalization for AP as a primary diagnosis was 4 days (interquartile range (IQR) 2-7) as compared to 22 (11-37) for AP as a secondary diagnosis.

Conclusion(s)

Approximately one third of hospitalized patients had an underlying condition requiring treatments that could cause AP, which explains the high prevalence of drug-induced AP in this report. The longest hospitalizations were associated with AP as secondary diagnosis. Ongoing work will identify factors associated with disease severity and outcome in particular in primary AP.

Please acknowledge all funding agencies by checking the applicable boxes below

None

Disclosure of Interest

None Declared
Evaluating deployment strategies for spotted lanternfly (Lycorma delicatula Hemiptera: Fulgoridae) traps
Authors: Nixon Laura J , Barnes Caitlin , Deecher Elizabeth , Madalinska Katarzyna , Nielsen Anne , Urban Julie , Leskey Tracy C
Published: March 2023

The spotted lanternfly, Lycorma delicatula (White) (Hemiptera: Fulgoridae), is an invasive planthopper that was first detected in the United States in Berks County, PA, in 2014, and has since spread to 13 states in the Eastern United States. This phloem-feeding pest has a broad host range, including economically important crops such as grapevine, Vitis spp. Monitoring presence and relative abundance of L. delicatula is essential to develop pest management tools. Here, we compared deployment strategies to optimize use of L. delicatula monitoring traps. Standard circle traps, sticky bands, and circle traps with replaceable bag tops were deployed at sites with either high or low populations present. Trap deployment at different heights and on different host tree species and trap sampling intervals were evaluated for standard circle traps only. Circle traps captured significantly more L. delicatula adults at low-density sites compared with other trap types in 2021, and no differences were detected at high-density sights. Traps deployed 1 m from the ground captured significantly more adults than those deployed at 0.5 m; no differences were detected for nymphs. While no significant differences in captures were found among intervals, weekly or biweekly sampling prevented specimen degradation. Although traps deployed on Ailanthus altissima (Mill.) Swingle (Sapindales: Simaroubaceae) captured significantly or numerically more L. delicatula at most sites, traps deployed on other hosts also yielded consistent captures. We were also able to alter the construction of circle trap skirts to allow for deployment on different sized tree trunks.
Frequent and efficient harvesting as an economically viable strategy to regulate coffee berry borer on commercial farms in Hawaii
Authors: Aristizábal Luis F , Johnson Melissa A , Shriner Suzanne , Wall Marisa
Published: March 2023

Coffee is the second most economically important agricultural crop in Hawaii, valued at around $175M for green and roasted coffee in the 2021–2022 season. With the introduction of coffee berry borer (CBB, Hypothenemus hampei Ferrari) to Hawaii in 2010, growers have faced a significant challenge in producing the specialty coffee that the region is known for. This tiny beetle infests the coffee seed and reduces the yield and quality of coffee products. While field sanitation, frequent harvesting and strip-picking are known to be essential for controlling CBB, the associated costs and benefits of these cultural control practices have not been estimated for Hawaii. In the present study, we examined two CBB management strategies across 10 commercial coffee farms on Hawaii Island: (i) conventional management including frequent sprays of pesticides and few rounds of sanitation and harvesting, and (ii) cultural control-focused management consisting of few sprays of pesticides and frequent sanitation and harvesting. Cultural management resulted in significantly lower mean CBB infestation (4.6% vs. 9.0%), total defects (5.5% vs. 9.1%), and CBB damage to processed coffee (1.6% vs. 5.7%) compared to conventional management. Additionally, yields were higher (mean increase of 3,024 lbs of cherry/acre) and harvested more efficiently (4.8 vs. 7.9 raisins/tree) on culturally managed vs. conventional farms. Lastly, the cost of chemical controls was 55% lower and the net benefit of frequent harvesting was 48% higher on cultural vs. conventional farms. Our findings demonstrate that frequent and efficient harvesting is an effective and economically viable alternative to frequent pesticide applications.
Laminarin-triggered defence responses are geographically dependent in natural populations of Solanum chilense
Authors: Kahlon Parvinderdeep S , Förner Andrea , Muser Michael , Oubounyt Mhaned , Gigl Michael , Hammerl Richard , Baumbach Jan , Hückelhoven Ralph , Dawid Corinna , Stam Remco
Published: March 2023

Natural plant populations are polymorphic and show intraspecific variation in resistance properties against pathogens. The activation of the underlying defence responses can depend on variation in perception of pathogen-associated molecular patterns or elicitors. To dissect such variation, we evaluated the responses induced by laminarin (a glucan, representing an elicitor from oomycetes) in the wild tomato species Solanum chilense and correlated this to observed infection frequencies of Phytophthora infestans. We measured reactive oxygen species burst and levels of diverse phytohormones upon elicitation in 83 plants originating from nine populations. We found high diversity in basal and elicitor-induced levels of each component. Further we generated linear models to explain the observed infection frequency of P. infestans. The effect of individual components differed dependent on the geographical origin of the plants. We found that the resistance in the southern coastal region, but not in the other regions, was directly correlated to ethylene responses and confirmed this positive correlation using ethylene inhibition assays. Our findings reveal high diversity in the strength of defence responses within a species and the involvement of different components with a quantitatively different contribution of individual components to resistance in geographically separated populations of a wild plant species.
MR elastography identifies regions of extracellular matrix reorganization associated with shorter survival in glioblastoma patients
Authors: Svensson Siri Fløgstad , Halldórsson Skarphéðinn , Latysheva Anna , Fuster-Garcia Elies , Hjørnevik Trine , Fraser-Green Jorunn , Birkeland Bugge Robin Anthony , Grinband Jack , Holm Sverre , Sinkus Ralph , Vik-Mo Einar Osland , Emblem Kyrre Eeg
Published: March 2023

Background

Biomechanical tissue properties of glioblastoma tumors are heterogeneous, but the molecular mechanisms involved and the biological implications are poorly understood. Here, we combine magnetic resonance elastography (MRE) measurement of tissue stiffness with RNA sequencing of tissue biopsies to explore the molecular characteristics of the stiffness signal.

Methods

MRE was performed preoperatively in 13 patients with glioblastoma. Navigated biopsies were harvested during surgery and classified as “stiff” or “soft” according to MRE stiffness measurements (|G*|norm). Twenty-two biopsies from eight patients were analyzed by RNA sequencing.

Results

The mean whole-tumor stiffness was lower than normal-appearing white matter. The surgeon’s stiffness evaluation did not correlate with the MRE measurements, which suggests that these measures assess different physiological properties. Pathway analysis of the differentially expressed genes between “stiff” and “soft” biopsies showed that genes involved in extracellular matrix reorganization and cellular adhesion were overexpressed in “stiff” biopsies. Supervised dimensionality reduction identified a gene expression signal separating “stiff” and “soft” biopsies. Using the NIH Genomic Data Portal, 265 glioblastoma patients were divided into those with (n = 63) and without (n = 202) this gene expression signal. The median survival time of patients with tumors expressing the gene signal associated with “stiff” biopsies was 100 days shorter than that of patients not expressing it (360 versus 460 days, hazard ratio: 1.45, P < .05).

Conclusion

MRE imaging of glioblastoma can provide noninvasive information on intratumoral heterogeneity. Regions of increased stiffness were associated with extracellular matrix reorganization. An expression signal associated with “stiff” biopsies correlated with shorter survival of glioblastoma patients.
Autoimmunity in Long Covid and POTS
Authors: El-Rhermoul Fatema-Zahra , Fedorowski Artur , Eardley Philip , Taraborrelli Patricia , Panagopoulos Dimitrios , Sutton Richard , Lim Phang Boon , Dani Melanie
Published: March 2023

Orthostatic intolerance and other autonomic dysfunction syndromes are emerging as distinct symptom clusters in Long Covid. Often accompanying these are common, multi-system constitutional features such as fatigue, malaise and skin rashes which can signify generalized immune dysregulation. At the same time, multiple autoantibodies are identified in both Covid-related autonomic disorders and non-Covid autonomic disorders, implying a possible underlying autoimmune pathology. The lack of specificity of these findings precludes direct interpretations of cause and association, but their prevalence with its supporting evidence is compelling.
Plants use molecular mechanisms mediated by biomolecular condensates to integrate environmental cues with development
Authors: Field Sterling , Jang Geng-Jen , Dean Caroline , Strader Lucia C , Rhee Seung Y
Published: March 2023

This review highlights recent literature on biomolecular condensates in plant development and discusses challenges for fully dissecting their functional roles. Plant developmental biology has been inundated with descriptive examples of biomolecular condensate formation, but it is only recently that mechanistic understanding has been forthcoming. Here, we discuss recent examples of potential roles biomolecular condensates play at different stages of the plant life cycle. We group these examples based on putative molecular functions, including sequestering interacting components, enhancing dwell time, and interacting with cytoplasmic biophysical properties in response to environmental change. We explore how these mechanisms could modulate plant development in response to environmental inputs and discuss challenges and opportunities for further research into deciphering molecular mechanisms to better understand the diverse roles that biomolecular condensates exert on life.
Antagonistic regulation of target genes by the SISTER OF TM3–JOINTLESS2 complex in tomato inflorescence branching
Authors: Wang Xiaotian , Liu Zhiqiang , Bai Jingwei , Sun Shuai , Song Jia , Li Ren , Cui Xia
Published: March 2023

Inflorescence branch number is a yield-related trait controlled by cell fate determination in meristems. Two MADS-box transcription factors (TFs)—SISTER OF TM3 (STM3) and JOINTLESS 2 (J2)—have opposing regulatory roles in inflorescence branching. However, the mechanisms underlying their regulatory functions in inflorescence determinacy remain unclear. Here, we characterized the functions of these TFs in tomato (Solanum lycopersicum) floral meristem and inflorescence meristem (IM) through chromatin immunoprecipitation and sequencing analysis of their genome-wide occupancy. STM3 and J2 activate or repress the transcription of a set of common putative target genes, respectively, through recognition and binding to CArG box motifs. FRUITFULL1 (FUL1) is a shared putative target of STM3 and J2 and these TFs antagonistically regulate FUL1 in inflorescence branching. Moreover, STM3 physically interacts with J2 to mediate its cytosolic redistribution and restricts J2 repressor activity by reducing its binding to target genes. Conversely, J2 limits STM3 regulation of target genes by transcriptional repression of the STM3 promoter and reducing STM3-binding activity. Our study thus reveals an antagonistic regulatory relationship in which STM3 and J2 control tomato IM determinacy and branch number.
Relationship between lysine methyltransferase levels and heterochromatin gene repression in living cells and in silico
Authors: Yan Xiaokang , Williams Michael R , Barboza Castillo Ameriks D , Kireev Dmitri , Hathaway Nathaniel A
Published: March 2023

Gene regulation plays essential roles in all multicellular organisms, allowing for different specialized tissue types to be generated from a complex genome. Heterochromatin-driven gene repression, associated with a physical compaction of the genome, is a pathway involving core components that are conserved from yeast to human. Posttranslational modification of chromatin is a critical component of gene regulation. Specifically, tri-methylation of the nucleosome component histone 3 at lysine 9 (H3K9me3) is a key feature of this pathway along with the hallmark heterochromatin protein 1 (HP1). Histone methyltransferases are recruited by HP1 to deposit H3K9me3 marks which nucleate and recruit more HP1 in a process that spreads from the targeting site to signal for gene repression. One of the enzymes recruited is SETDB1, a methyltransferase which putatively catalyzes posttranslational methylation marks on H3K9. To better understand the contribution of SETDB1 in heterochromatin formation, we downregulated SETDB1 through knockdown by a dCas9-KRAB system and examined heterochromatin formation in a chromatin in vivo assay (CiA-Oct4). We studied the contribution of SETDB1 to heterochromatin formation kinetics in a developmentally crucial locus, Oct4. Our data demonstrate that SETDB1 reduction led to a delay in both gene silencing and in H3K9me3 accumulation. Importantly, SETDB1 knockdown to a ∼50% level did not stop heterochromatin formation completely. Particle-based Monte Carlo simulations in 3D space with explicit representation of key molecular processes enabled the elucidation of how SETDB1 downregulation affects the individual molecular processes underlying heterochromatin formation.
Very Small Embryonic-Like Stem Cells Transform Into Cancer Stem Cells and Are Novel Candidates for Detecting/Monitoring Cancer by a Simple Blood Test
Authors: Bhartiya Deepa , Sharma Nripen , Dutta Shruti , Kumar Piyush , Tripathi Ashish , Tripathi Anish
Published: March 2023

Cancer continues to remain a “Black Box,” as there is no consensus on how it initiates, progresses, metastasizes, or recurs. Many imponderables exist about whether somatic mutations initiate cancer, do cancer stem cells (CSCs) exist, and if yes, are they a result of de-differentiation or originate from tissue-resident stem cells; why do cancer cells express embryonic markers, and what leads to metastasis and recurrence. Currently, the detection of multiple solid cancers through liquid biopsy is based on circulating tumor cells (CTCs) or clusters, or circulating tumor DNA (ctDNA). However, quantity of starting material is usually adequate only when the tumor has grown beyond a certain size. We posit that pluripotent, endogenous, tissue-resident, very small embryonic-like stem cells (VSELs) that exist in small numbers in all adult tissues, exit from their quiescent state due to epigenetic changes in response to various insults and transform into CSCs to initiate cancer. VSELs and CSCs share properties like quiescence, pluripotency, self-renewal, immortality, plasticity, enrichment in side-population, mobilization, and resistance to oncotherapy. HrC test, developed by Epigeneres, offers the potential for early detection of cancer using a common set of VSEL/CSC specific bio-markers in peripheral blood. In addition, NGS studies on VSELs/CSCs/tissue-specific progenitors using the All Organ Biopsy (AOB) test provide exomic and transcriptomic information regarding impacted organ(s), cancer type/subtype, germline/somatic mutations, altered gene expressions, and dysregulated pathways. To conclude, HrC and AOB tests can confirm the absence of cancer and categorize the rest of subjects into low/moderate/high risk of cancer, and also monitor response to therapy, remission, and recurrence.
Physiological and transcriptomic characterization of cadmium toxicity in Moso bamboo (Phyllostachys edulis), a non-timber forest species
Authors: Yang Fan , Chang Yu Zhen , Zheng Yi Ting , Pan Xianyu , Ji Haibao , Shao Ji Feng
Published: March 2023

Cadmium pollution in Moso bamboo forests poses a potential threat to the sustainable development of the bamboo industry. However, the effects of cadmium toxicity on Moso growth and its mechanisms of adaptation to cadmium stress are poorly understood. In this study, the physiological and transcriptional response of Moso to cadmium stress was investigated in detail using Moso seedlings in a hydroponic system. Cadmium toxicity severely inhibited the growth of roots but had little effect on biomass accumulation in the aerial parts. Cadmium accumulation in roots and aerial parts increased as external cadmium increased, with cadmium mainly localized in the epidermis and pericycle cells in the roots. The uptake and root-to-shoot translocation of cadmium was stimulated, but the photosynthetic process was suppressed under cadmium stress. A total of 3469 differentially expressed genes were identified from the transcriptome profile and those involved in cadmium uptake, transportation and detoxification were analyzed as candidates for having roles in adaptation to cadmium stress. The results suggested that Moso is highly efficient in cadmium uptake, xylem loading and translocation, as well as having a high capacity for cadmium accumulation. This work also provided basic information on physiological and transcriptional responses of Moso to cadmium toxicity.