bluuebunny/crossref_metadata_2025_split huggingface dataset:
A39 IMPACT OF AN ENDOSCOPIC OPTICAL DIAGNOSIS COURSE ON GASTROINTESTINAL NEOPLASM CHARACTERIZATION SKILLS AMONG TRAINEE ENDOSCOPISTS
Authors: Tran W , Gimpaya N , Khan R , Walsh C , Hookey L , Rai M , Grover S , Bechara R 
Published: February 2025

Abstract

Background
Real-time endoscopic optical diagnosis involves detailed visualization of the digestive mucosal and microvascular pattern, allowing for prediction of histology. This is advantageous as it can guide endoscopic resection decisions, surgical referrals and provide cost savings to histopathology. There is, however, no standardized or widely implemented curriculum for endoscopists or trainees to learn optical diagnosis skills.

Aims
To evaluate the impact of a course for the optical diagnosis of esophageal squamous cell carcinoma (ESCC), early gastric cancer (EGC), Barrett’s esophagus (BE), and colorectal polyps

Methods
19 gastroenterology trainees were invited to the 2-day course in Kingston, Canada. Number of procedures previously performed was recorded. The impact of the course on lesion diagnosis accuracy was evaluated using a pre-test, immediate post-test, and delayed post-test administered 6 weeks after the course. A repeated measures ANOVA was performed to compare the mean score (%) between the three tests.

Results
13 trainees completed all the tests (Table 1). Mean score % values for the overall tests and test scores for esophageal, gastric, and colon lesions were summarized on Table 1. The repeated measures ANOVA determined that the mean score % had a statistically significant difference between the three tests (F (2,24)=5.63, P=0.01). Pairwise comparisons revealed that there was a statistically significant increase in mean scores between pre- and post-tests (13.86 (95% confidence interval (CI) of 4.36 to 23.33), p&lt;0.01) with no significant difference between post and delayed post-tests (8.46 (95% CI of -0.12 to 17.04), p&gt;0.05) (Figure 1). The mean correct % from the delayed post-test was higher than the pre-test but there was no statistical significance (5.39 (95% CI of -3.72 to 14.49), p&gt;0.05).

Conclusions
This novel optical diagnosis course improved trainee accuracy in diagnosing ESCC, EGC, BE and colorectal polyps. Learning retention was evident, with no significant score difference between immediate and delayed post-tests. This study was limited by the low sample size and low number of test items. Further investigation is required to validate the course for international trainees and explore its clinical transferability.
Demography and Mean Score %

Figure 1. Mean score %. (*) denotes p&lt;0.05.

Funding Agencies
None
A41 OUTCOMES FROM ESOPHAGEAL STENT PLACEMENT FOR REFRACTORY BENIGN ESOPHAGEAL STRICTURES
Authors: Yau M , Donnellan F , Byrne M F , Gan S , Trasolini R 
Published: February 2025

Abstract

Background
A benign esophageal stricture (BES) is an esophageal narrowing that causes dysphagia in the absence of inflammation. First-line treatment for BES is esophageal bougie or balloon dilation. Esophageal stent placement is a treatment option for refractory benign esophageal strictures (RBES) but comes with significant complication risks.

Aims
We aim to assess complications following esophageal stent placement for RBES and whether there are differences in migration rates depending on the stent length, stent width, and presence of clip or suture fixation.

Methods
This is a retrospective cohort study of adult patients with RBES who were treated with esophageal stent placement at the Vancouver General Hospital, Vancouver, Canada between Jan. 1st, 2016 and Aug. 20th, 2024. We excluded patients with malignant esophageal strictures and esophageal leakages. Data was manually extracted via patient chart review.

Results
12 patients received a total of 32 esophageal stents for RBES. 50.0% of patients had peptic strictures. 33.3% of patients had anastomotic strictures post-esophagectomy. Other causes included Barrett’s esophagus and brachytherapy. Patients received on average 7 dilations before their first stent placement. Average stent indwell time was 157 days. All stents were fully covered and metal. The average number of stents placed was 3. The average number of adverse events was 4. 87.5% of stents led to adverse events. 53.1% (17 of 32 stents) of stents migrated. 12.5% (4 of 32 stents) of stents caused granulation tissue. Stent ingrowth occurred in 6.25% of stents placed (2 of 32 stents). Other adverse events included gastrointestinal bleed, ulcers, food obstruction, dysphagia, odynophagia, chest pain, and abdominal pain. 33.3% of patients required hospitalization from adverse events. No deaths or critical care stays occurred from adverse events. 25.0% of stents were fixed with clips, padlock clips, or sutures. Risk of migration did not statistically differ between fixation and no fixation (50.0% vs 54.2%, p&gt;0.05). Short (less than 12cm) and wide stents (greater than 18mm) were less likely to migrate as compared to long and narrow stents (52.0% vs 57.1%, p&lt;0.05; 42.9% vs 62.5%, p&lt;0.05; respectively).

Conclusions
Esophageal stent placement is an appropriate treatment for RBES. Although adverse events occurred in most stents placed, most were mild and manageable with appropriate counselling and intervention. No adverse events occurred leading to death or critical care stay. Guidelines from the European Society of Gastrointestinal Endoscopy recommend a maximum indwell time of 12 weeks, but in select circumstances longer indwell times are possible.
Funding Agencies:
A43 TOPICAL HEMOSTATIC AGENTS: A POTENTIAL BREAKTHROUGH IN MALIGNANCY-RELATED GI BLEEDING? A SYSTEMATIC REVIEW AND META-ANALYSIS OF RANDOMIZED CONTROLLED TRIALS
Authors: Minhas G S , Bukhari A , Yuan Y , Leontiadis G , Laine L , Barkun A , Tse F 
Published: February 2025

Abstract

Background
Malignancy-related gastrointestinal bleeding (GIB) has been challenging to treat with conventional endoscopic techniques. Topical hemostatic agents (THAs), which do not cause mucosal injury and can be applied over large surface areas, may offer a promising solution in cancer-related GIB.

Aims
To assess the effectiveness and safety of THAs in malignancy-related GIB compared to conventional endoscopic techniques.

Methods
We conducted a systematic review using MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials until March 2024. RCTs that compared THA vs conventional endoscopic techniques in malignant GIB were included. Two authors conducted study selection, data extraction and quality assessment independently. The primary outcome was 30-day further bleeding. Further bleeding is a composite outcome of failure to achieve immediate hemostasis and rebleeding. Secondary outcomes included failure to achieve immediate hemostasis, 6-month mortality, 30-day rebleeding, blood transfusions needed, length of hospitalization, and adverse events. RevMan 5.4 was used to calculate pooled risk ratios (RR) with 95% confidence intervals (CI, random effects model). Heterogeneity was assessed by Chi 2 (P&lt;0.15) and I 2 tests (&gt;25%). We assessed the certainty of evidence (CoE) for each outcome using the GRADE approach.

Results
Results: We identified 5100 citations and 4 RCTs with 122 patients were included in the analysis. There was no significant difference between THA and conventional endoscopic methods with respect to 30-day further bleeding through THAs reduce the risk of immediate hemostatic failure. There was no significant difference noted in 30-day rebleeding. THAs did not significantly impact 6-month mortality or blood transfusions. THAs were found to increase the average length of hospitalization by 4.28 days.

Conclusions
TC-325 appears superior to conventional endoscopic techniques in achieving immediate hemostasis for malignancy-related
GIB. It may reduce further bleeding over 30 days as well, but the evidence is very uncertain and further research is needed to assess bleeding risk over this period and beyond. TC-325 did not appear to reduce 6-month mortality.
Table 1. Summary of Findings

Forest plot of further bleeding
Funding Agencies:
A44 ENDOSCOPISTS PERFORMING ADVANCED UPPER GI ENDOSCOPY ARE AT HIGHER RISK OF FACIAL BACTERIAL CONTAMINATION
Authors: Baeg M , Ko S 
Published: February 2025

Abstract

Background
Gastrointestinal (GI) endoscopy has been recognized as putting endoscopists at risk for bacterial exposure. However, whether longer, more advanced procedures such as endoscopic submucosal dissection (ESD) or endoscopic retrograde cholagiopancreatography (ERCP) confer greater risk has not been investigated.

Aims
This study aimed to investigate the degree of exposure on endoscopists who performed ESD or ERCP and find out if longer time or procedure type are risk factors for exposure.

Methods
This was a prospective study examining the facemasks of endoscopists who performed ESD or ERCP at a university hospital, with 40 procedures planned for each procedure. The face shield was swabbed in a standardized way before and at the end of the procedure. Swabs were also taken from face shields placed 2 meters away on the endoscopy suite wall, patient recovery room wall, and after direct contamination by the endoscope immediately after the procedure. The swabs were cultured for 48 hours, and growth was reported as no growth or by number of colony-forming units (CFUs). The groups were compared for +CFU rate. Risk of contamination was analyzed by procedure time and type.

Results
55 ESDs and ERCPS were performed during the study dates. It was decided to terminate the study early, due to the COVID-19 situation, as facemasks were deemed too important to be used for walls. Excluding one facemask group in which the endoscopist’s facemask was exposed before the procedure, 54 groups of masks were analyzed. There were 33 ESDs and 21 ERCPS performed, with 26 upper GI and 7 lower GI ESDs. A cut-off of 30 CFUs were determined as indication of definite exposure. Interestingly, none of the 7 lower GI ESDs resulted in any exposure, so it was decided to analyze only the 47 orally inserted procedures. There were 9 positive exposures, 6 ESDs (23.1%) and 3 ERCPs (14.3%). Mean procedure time was 30.3 ± 15.2 minutes. Procedure time (Odds ratio 1.014, 0.968-1.061, P=0.564) and type (ERCP compared to ESD, OR 0.556, 0.121-2.553, P=0.556) were not positive risk factors for contamination. The most commonly cultured pathogens were Staphylococcus, Streptococcus, Bacillus, and Moraxella species.

Conclusions
This study confirmed that advanced procedures such as upper GI ESDs and ERCPs have a high risk of facial exposure. Facemasks and other protective equipment should be used during GI endoscopy.
Basic Characteristics of Endoscopy

ESD - endoscopic submucosal dissection, ERCP - endoscopic retrograde cholangiopancreatography

Funding Agencies
None
A49 PROSPECTIVE PAIRED COMPARISON STUDY OF 2 FRANSEEN-TIP EUS FNB NEEDLES, FLEXIBLE VS STIFF SHEATH
Authors: Borahmah F , Motomura D , Trasolini R 
Published: February 2025

Abstract

Background
Variety of needle tips and suction techniques have been trialled to optimize diagnostic yield in EUS-FNB for comprehensive histopathological analysis with some studies suggesting improved performance with franseen tip needle

Aims
Obtain an objective comparison of diagnostic yield between 2 different 22g franseen-tip needles; novel flexible sheath (FS) franseen tip needle and traditional stiff sheath (SS) needle

Methods
Sample of patients presenting for outpatient elective EUS-FNB were selected.
Underwent EUS-FNB using both a SS and FS FNB needle during same procedure.
Equal number of passes was obtained with each needle by same endoscopist with random order of sampling, with a planned number of 2 passes per needle; not obtained for one lesion due to difficulty with puncture.
Obtained specimens were sent to pathology; quality of sampling was assessed by the pathologist and cellularity was recorded as a percentage.
In procedures where one needle was unable to puncture or an acellular specimen was obtained a score of 0 was given.
Paired 2 tailed t-test was performed for comparison of mean cellularity. Hazard ratio was calculated for risk of obtaining a non-diagnostic sample

Results
SS mean cellularity 45.7% SD 25.7
FS mean cellularity 72.9% SD 17.0
Difference in mean cellularity 27.2% two-tailed p-value=.08
Hazard ratio of obtaining a non-diagnostic sample with SS: HR 5 p=0.28
No statistically significant difference in results but a numerical trend is noted.
Analysis demonstrates variability in cellularity of specimens obtained with each needle type; 6/8 specimens showed higher cellularity with FS needle while only 1/8 showed higher cellularity with SS.
In 2 cases, both similar lesion types in different patients, non-diagnostic specimens were obtained by SS. One patient due to inability to puncture and in a second due to inadequate cellularity

Conclusions
Results may suggest presence of tissue characteristics or lesion-specific factors that influenced the sampling efficacy.
Findings can provide potential insight into optimizing selection of biopsy needle designs and is a novel look at an uncommonly analyzed aspect of FNB needle design, namely sheath stiffness.
Several limitations of this study, primarily the small sample size
Further research with larger cohorts is needed to compare the diagnostic yields of needle types.
Despite preliminary nature of these results, this study contributes real world paired comparison data

Funding Agencies:
A53 NOVEL PROTEASE–HISTAMINE INTERACTIONS POTENTIATE PAIN SIGNALING EVOKED BY FECAL SUPERNATANTS FROM IBS PATIENTS
Authors: Jimenez Vargas N , Gilmour D A , Sokrat B , Bennett A S , Lomax A E , Reed D E , Bunnett N W , Vanner S J 
Published: February 2025

Abstract

Background
Proteases and histamine, originating from intestinal tissue and/or the microbiota, have each been implicated in the severe pain symptoms reported by patients with irritable bowel syndrome (IBS). However, the effects of their combined signaling and the mechanisms involved have not been studied.

Aims
To determine whether histamine and trypsin synergistically enhance colonic nociceptive signaling and, if so, to study the mechanisms involved.

Methods
Fecal supernatants (FS) were obtained from IBS patients with low and high pain scores. Responses to luminal application of FS, histamine and protease (trypsin) and antagonists (H1R-pyrilamine, PAR2-GB83) were studied using ex vivo mouse colonic afferent nerve recordings. In mechanistic studies, excitability of isolated mouse dorsal root ganglia (DRG) neurons was measured using patch clamp recordings of rheobase after combined or sequential application of agonists. To study endosomal signaling, neurons were incubated with clathrin inhibitor, pitstop2, before agonists. Using HEK cells, recruitment of mGαq to PAR2 and H1R at the plasma membrane (CAAX) or early endosome (Rab5) was measured using bioluminescence resonance energy transfer (BRET) in response to sequential application of increasing doses of trypsin and histamine.

Results
In colonic afferent nerve recordings, FS from IBS patients with high pain scores increased mechanosensitivity (50%; p &lt;0.001) and this was blocked by either a PAR2 and H1R antagonist, whereas FS from those with low pain scores had no effect. Trypsin and histamine at subthreshold concentrations (30 μM) alone had no effect. However, their co-application increased afferent mechanosensitivity (46%; p &lt;0.001); similar effects were observed in patch clamp recordings from DRG neurons (rheobase decreased 33%; p &lt;0.05). To study the mechanism of this synergistic interaction, DRG neurons were recorded after a sequential incubation with histamine and proteases. Incubation first with histamine had no effect (p=0.55) on the subsequent trypsin-mediated PAR2 excitability but incubation first with trypsin amplified the histamine response by 42 % (p&lt;0.01). This PAR2-mediated action was blocked by inhibitors of endosomal signaling. In keeping with these findings, BRET studies revealed that incubation first with trypsin promoted mGαq recruitment to the plasma membrane and early endosomes, whereas histamine did not.

Conclusions
Conclusion: FS from IBS patients with high pain scores caused exaggerated pain signaling from the mouse colon and was mediated by the synergistic action of histamine and proteases. Mechanistic studies revealed a novel pathway where trypsin-mediated PAR2 endosomal signaling amplified histamine-evoked pain signaling. These findings could inform future studies of IBS therapies and biomarkers.

Funding Agencies
CIHR
A55 CHRONIC STRESS IMPAIRS THE INTESTINAL CRYPTAL STEM CELL CYCLE AND PANETH CELL PROLIFERATION
Authors: BAI X 
Published: February 2025

Abstract

Background
The small intestine’s epithelial barrier is essential for intestinal homeostasis and host defense. It consists of epithelial cells constantly renewed by crypt stem cells and their progeny, which have different functions in the gut. Chronic stress can impair the barrier by modulating the gut-brain axis, which involves the hypothalamic-pituitary-adrenal (HPA) axis, the vagus nerve, and the immune system. Chronic stress can also alter the gut microbiota, further influencing the barrier and immune system.

Aims
The present study examines how chronic stress affects the crypt stem cell niche and function in the small intestine.

Methods
Restraint stress was applied to 6-8 weeks-old mice in a plastic container for 1 hour daily for 7 days. The dark/light transition box test evaluated stress-induced behavior change. The Ussing chamber technique was used to assess the paracellular permeability of the small intestine. RNA was extracted from the mucosa and submucosa layers of the small intestine, after removing the muscle layer, and RNA sequencing analysis was performed. Immunofluorescence analysis was also performed on the small intestinal tissues to detect the expression of various markers. To assess the in vivo effect of cortisol, dexamethasone (a synthetic steroid activating the same receptors as cortisol), or metyrapone (an 11β-hydroxylation blocker to inhibit cortisol production), was applied. To assess the possible involvement of microbiota, antibiotics were applied before and during the restraint stress.

Results
We found that restraint stress-induced anxiety-like behavior, increased small intestinal epithelial permeability and reduced villus and crypt length in mice. RNA sequencing analysis revealed that restraint stress downregulated the markers of Paneth cells and stem cells in the small intestinal mucosa. Immunofluorescence analysis confirmed that restraint stress reduced the expression of stem cell marker Olfm-4 and proliferation markers Ki-67 and p-H3 in the small intestinal crypts. 16s rRNA analysis showed increased Streptococcus and decreased Bifidobacterium in stressed mice fecal samples. Ablation of gut microbiota by antibiotics attenuated the stress-induced downregulation of stem cell markers but did not affect the Paneth cell markers. Dexamethasone, a synthetic glucocorticoid, mimicked the effects of restraint stress on crypt stem cells and Paneth cells, while metyrapone, a steroid synthesis inhibitor, attenuated both.

Conclusions
Chronic stress induces anxiety, gut microbiota alteration, and barrier dysfunction. The change in epithelial villi and crypts in the small intestine is in a microbiota-dependent manner. These findings show how chronic stress impacts intestinal epithelial renewal and differentiation, which may affect intestinal health and disease.

Funding Agencies
JSPS KAKENHI
A59 IMPACT OF ISOVALERATE SUPPLEMENTATION ON MURINE ANTIBODY RESPONSES DURING ENTERIC HELMINTH INFECTION
Authors: Norton N J , Lane J M , FitzPatrick R D , Gatti D M , Jensen E L , Reynolds L A 
Published: February 2025

Abstract

Background
Parasitic worm (helminth) infections significantly contribute to human morbidity, with nearly one fifth of the global population chronically infected. Our lab has shown that levels of the short chain fatty acid isovalerate are increased during a murine intestinal helminth infection and that isovalerate supplementation increases helminth fecundity, implying increased worm fitness.

Aims
Our research aims to elucidate the potential immunomodulatory impact of isovalerate during enteric helminth infection.

Methods
Using the small intestinal-colonizing mouse roundworm, Heligmosomoides polygyrus (Hp), to model enteric helminth infections, we examined the influence of isovalerate supplementation in the drinking water on total and Hp antigen-specific antibody responses during primary (1o) & secondary (2o) Hp infections in both sexes of C57BL/6J mice. Circulating and mucosal antibody responses were analyzed using enzyme-linked immunosorbent assays and the impact of isovalerate supplementation on lymphocyte populations was assessed in the gut-draining lymph nodes, the spleen, and Peyer’s Patches using flow cytometry.

Results
Data from one experimental repeat shows a trending reduction in total systemic and total mucosal IgA concentrations in 1oHp infected mice that were supplemented with isovalerate, compared to mice on control drinking water. In mice supplemented with isovalerate in the 2oHp infection model, one experimental repeat shows that isovalerate supplementation does not impact susceptibility to challenge infection or elicit changes to circulating or mucosal antibody levels.

Conclusions
Preliminary data suggest that isovalerate supplementation may impact total systemic and mucosal antibody concentrations during a 1oHp infection. Ongoing work includes solidifying our preliminary findings with experimental repeats. Future work will assess the impact of isovalerate supplementation on B cell development and antibody concentrations at steady state as well as during infection and elucidate the signalling mechanisms of isovalerate in vivo and in vitro. Furthering our understanding of how isovalerate affects the antibody response during a helminth infection may reveal novel immunomodulatory mechanisms in the intestine and may be applicable to other gut-restricted diseases.

Funding Agencies
CIHRTRIANGLE
A61 GLOBAL INCIDENCE OF APPENDICITIS: A POPULATION-BASED STUDY OF THE ORGANISATION FOR ECONOMIC CO-OPERATION AND DEVELOPMENT
Authors: Buie E , Coward S , Buie M J , King J A , Wilson L M , Quan M , Gimon T , Kaplan G G 
Published: February 2025

Abstract

Background
The global incidence of appendicitis in 2019 was estimated at 228 per 100,000 person-years. However, temporal trends of appendicitis rates vary between early industrialized and newly industrialized regions.

Aims
To analyze annual appendectomy rates in regions of the Organisation for Economic Co-operation and Development (OECD) in the 21st century.

Methods
We conducted an observational population-based cohort study using data from 34 OECD regions from 2000–2023. OECD data provides country-level annual hospitalization rates for appendectomy per 100,000 person-years. We used Poisson regression to calculate Average Annual Percentage Change (AAPC) in appendectomy rates, with associated 95% confidence intervals (CI) for each region. CIs crossing 0% were defined as stable.

Results
We observed geographic variation in appendectomy incidence rates, with rates ranging from 56.8 per 100,000 in Portugal (2023) to 165.6 per 100,000 in Switzerland (2022) (Table 1). Appendectomy rates significantly decreased in 22 regions and significantly increased in 10 regions, with AAPCs ranging from −4.25% (95%CI: −4.28, −4.22) in Italy to 1.46% (95%CI: 1.23, 1.68) in Norway (Table 1). AAPCs in Iceland were stable, and Latvia had insufficient data for time trend analysis.

Conclusions
In the 21st century, time trends of appendectomy rates across OECD regions displayed variation, with the majority decreasing. Geographic variability in rates and trends over time may be due to factors such as differential access to improved diagnostic imaging and non-surgical treatments.
Table 1. The Average Annual Percentage Change (AAPC) in appendectomy for the 34 regions of the OECD dataset with the corresponding year ranges for each region, confidence intervals, and associated average incidence per 100,000 person-years. All region AAPCs are significantly increasing or decreasing except Iceland and Latvia.

Funding Agencies
None