bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prevalence of Plasmodium falciparum Drug Resistance Markers pfcrt K76T and pfaat1 S258L in Southern Rwanda, 2010 to 2023
Authors: Schallenberg Emma , van Loon Welmoed , Mbarushimana Djibril , Igiraneza Clement , Glanz Karolina , Ngarambe Christian , Minega Ndoli Jules , Hendry Jason A , Mockenhaupt Frank P 
Published: February 2025

Abstract

Background
In many countries in Sub-Saharan Africa, the Plasmodium falciparum chloroquine resistance marker pfcrt K76T disappeared within a decade after use of chloroquine ceased. pfaat1 S258L has recently been implicated as another chloroquine resistance marker. Both genes may affect parasite susceptibility to partner drugs in artemisinin-based combination therapy. Rwanda abolished chloroquine use in 2001, and since 2006 the first-line antimalarial is artemether-lumefantrine. However, partial artemisinin resistance emerged in the region. We assessed the prevalence of pfcrt and pfaat1 markers in Huye district between 2010 and 2023, following trends and updating the status in southern Rwanda.

Methods
P. falciparum-positive blood samples from community children and malaria patients collected in 2010, 2014, 2018, 2019, and 2023 were examined. pfcrt K76T was genotyped by restriction fragment length polymorphism, and pfaat1 S258L by high-resolution melting curve (2010–2019). Samples from 2023 were subjected to nanopore sequencing.

Results
In 606 samples, pfcrt K76T prevalence declined from 76% (95% confidence interval [CI], 68%–83%) to 18% (95% CI, 11%–25%) between 2010 and 2018 but remained constant since at around 25% (P &lt; .001). No other pfcrt markers were observed. pfaat1 S258L has remained at or near fixation. The artemisinin resistance marker pfk13 R561H was associated with pfcrt K76T (P = .02).

Discussion
The persistence of pfcrt K76T 20 years after abolishing chloroquine use indicates ongoing drug selection or importation. The fixation of pfaat1 S258L argues against a major fitness cost of this variant in Huye. Increases in partial artemisinin resistance in Rwanda and molecular markers indicate compromised lumefantrine efficacy. The observed pfcrt and pfaat1 signatures in the study area might be of use in guiding artemisinin partner drug alternatives.
Factors associated with harm in reported patient safety incidents and characteristics during health screenings in Korea: a secondary data analysis
Authors: Choe Jeongin , Woo Kyungmi 
Published: February 2025

Abstract

Background
Various health screenings are conducted in South Korea, including state-supported national health screenings, privately funded comprehensive health screenings, and employment-related or industry-specific screenings. Given the various risks of patient safety incidents during the health screening process and the lack of studies of incidents in this environment, this study aimed to analyse the types and characteristics of reported patient safety incidents during health screenings, the distribution of harm, and the impact of the incident types on harm.

Methods
We analysed patient safety incidents reported to the Korean Institute for Healthcare Accreditation (2017–22) using the World Health Organization’s framework for patient safety. We performed frequency analysis, chi-square tests, and binomial logistic regression analysis to identify the types and characteristics of reported patient safety incidents, the differences in the distribution of harm, and the impact of patient safety incident types on harm during health screenings.

Results
A total of 213 cases were included in the analysis. Over half of the patient safety incidents during health screenings resulted in harm to the patient, and examination-related incidents were the most frequent type of incident. Furthermore, reported patient safety incidents were more likely to occur during regular working hours, in the examination room, in hospitals with over 500 beds, and amongst patients in their 50s, with no significant differences in sex distribution. Significant differences were observed in the distribution of harm according to incident types (P &lt;.001) and patient age (P =.023). Controlling for patient and incident characteristics, the incident type was a determinant of harm. Amongst the incident types, medication/drug administration [adjusted odds ratio (aOR) = 29.730, 95% confidence interval (CI) = 6.081, 145.368], anaesthesia/sedation/treatments and procedures (aOR = 5.121, 95% CI = 1.002, 26.178), falls (aOR = 4.903, 95% CI = 2.022, 11.890), infections/injuries (aOR = 11.898, 95% CI = 1.082, 130.839), and other types of incidents (aOR = 8.719, 95% CI = 2.602, 29.212) increased the probability of harm compared to examination-related incidents.

Conclusion
This study underscores the critical need to manage high-risk patient safety incidents and implement systemic harm reduction strategies during health screenings. Encouraging the reporting of incidents, including near misses, alongside developing targeted interventions, is essential for enhancing patient safety. Future research should leverage larger datasets, consistent classification systems, and standardized data collection to generalize findings and advance prevention strategies, thereby improving the quality and safety of health screening services.
A5 USING AIR-LIQUID INTERFACE ORGANOID MONOLAYERS TO DEFINE MUCOSAL-MICROBE DYSFUNCTION IN PATIENTS WITH ULCERATIVE COLITIS
Authors: Gilliland A , Chen Y , Ng I , Han X , Kalisky I , Sham H , Xiong W , Bressler B , vallance B 
Published: February 2025

Abstract
NOT PUBLISHED AT AUTHOR’S REQUEST
Please acknowledge all funding agencies listed below
Funding Agencies: CCC, CIHRWeston Family Foundation
A6 INVESTIGATING THE RELATIONSHIP BETWEEN MUCOSAL INFLAMMATION AND PROTEOLYTIC ACTIVITY IN CROHN’S DISEASE
Authors: Szeto J , Rueda G H , Hann A , Constante M , Wang X , Deraison C , Vergnolle N , Butcher J , Stintzi A , Bercik P , Galipeau H , Armstrong D , Verdu E 
Published: February 2025

Abstract

Background
Dysregulated proteolytic activity (PA) has been detected in intestinal biopsy samples of individuals with inflammatory bowel disease (IBD) compared to healthy controls. It is known that increased microbial fecal PA precedes ulcerative colitis (UC) diagnosis in an at-risk population. Intestinal inflammation in UC is characterized by continuous ulceration, inflammation in Crohn’s disease (CD) is patchy in nature. Sites of inflammation in CD has been associated with altered mucosa-associated microbes and higher permeability, suggesting these could be localized sites of increased microbial PA.

Aims
To investigate whether inflamed mucosal areas in CD are associated with proteolytic microbiota and increased permeability.

Methods
CD patients in flare (n=23) were recruited at McMaster University Medical Centre and matched (or paired) biopsies were collected at colonoscopy from inflamed and adjacent (within 5 cm) non-inflamed sites. Biopsy mucosal-to-serosal 51Cr-EDTA flux rate and tissue conductance were measured with Ussing chambers. Total proteolytic (trypsin), elastase-like (FITC-elastin), and mucolytic (0.05% mucin plates) activities were also assessed in biopsies from both sites and in situ zymography was used to measure and localize elastase-like activity in biopsy samples. Mucosal brushing samples from the same participants were also collected and total RNA purified for metatranscriptomic analysis to characterize active microbial pathways with a focus on identifying highly expressed microbial proteases.

Results
Paracellular permeability and tissue conductance were greater in biopsies from inflamed areas than in biopsies from matched non-inflamed areas (p&lt;0.001). Elastase-like and mucolytic activities were higher in inflamed areas compared to matched non-inflamed areas (p&lt;0.05 and p=0.04, respectively), no significance was detected in total proteolytic activity. In situ zymography revealed greater elastase-like activity in inflamed areas compared to non-inflamed areas (p=0.04), localized to both the epithelial and submucosa layers in inflamed tissues but only to the epithelial layer in matched non-inflamed tissue. Preliminary analysis of the metatranscriptomics results suggests that specific microbial proteases may be increased at inflamed sites in CD.

Conclusions
Our results suggest that localised variations in tissue inflammation, PA and mucosal permeability in CD may be causally linked, providing a rationale for the patchy distribution of mucosal injury. We, therefore, hypothesize that microbial elastase-like activity promotes mucosal inflammation through barrier disruption. This mechanism could be targeted locally to prevent or modulate microbially associated PA with the aim of enhancing mucosal healing in IBD.
Funding Agencies:
A20 DIETARY ANTIGENS DELIVERED TO MICE IN EARLY LIFE INDUCE ANTIGEN-SPECIFIC REGULATORY AND TH1 CELLS AND THE DEVELOPMENT OF ORAL TOLERANCE
Authors: FitzPatrick R D , Przydatek A M , Gatti D M , Cartwright R A , Norton N J , Lane J M , Reynolds L A 
Published: February 2025

Abstract

Background
Oral tolerance is the active suppression of immune responses to antigens that are first encountered in the gut. When this process fails, food allergies or celiac disease can arise. Oral tolerance develops largely in early life, but despite this it has historically been studied using adult rodent models.

Aims
Our research aims to develop a robust mouse model to elucidate mechanisms of oral tolerance development in early life.

Methods
Mice were orally gavaged with ovalbumin (OVA) as a model food antigen or water as a control in an early life, pre-weaning window (2-3 weeks old). Following systemic challenges with OVA, oral tolerance was assessed by measuring circulating antibody levels (ELISAs) and cytokine responses of ex vivo stimulated splenocytes and gut-draining mesenteric lymph node (MLN) cells (cytometric bead arrays). To characterize OVA–specific T helper cell responses, OT-II cells (OVA-specific CD4+ T cells) were adoptively transferred into mouse pups and their phenotypes were assessed in the MLNs and spleen by flow cytometry following oral gavages of OVA or control water.

Results
BALB/cJ and C57BL/6J mice orally gavaged with OVA in early life had reduced levels of OVA-specific antibodies compared to controls after systemic challenges with OVA, indicating that oral tolerance had developed. Further, we determined the minimum dosage of oral OVA required to confer oral tolerance during early life. We found a suppression of cytokine production in response to OVA-stimulation in cultures of MLN cells or splenocytes, from mice orally exposed to OVA (‘tolerized’) in early life compared to cell cultures from control mice.
We found an increased frequency of OVA-specific regulatory T cells in the MLNs and spleen in response to oral OVA exposure compared to mice exposed to control water. We also found an increase in the frequency of OVA-specific Th1 cells along with an increase in OVA-specific CD4+ T cells that are producing IFNγ when pups were exposed to oral OVA compared to control water.

Conclusions
We have developed a robust early life mouse model of oral tolerance. Our data suggests that oral tolerance is induced during early life in part following the central dogma of oral tolerance development elucidated in adult mice: with the induction of food-antigen specific regulatory T cells. However, we have also identified an increase in the frequency of food antigen-specific Th1 cells in the MLNs and spleen in response to oral antigen exposure during an early life, pre-weaning window. Future work will determine if IFNγ-expressing Th1 cells are essential for the development or maintenance of oral tolerance.

Oral tolerance development in early life.

Funding Agencies
CIHRTRIANGLE
A23 INVESTIGATING THE LINK OF BACTERIAL TRANSLOCATION AND BEHAVIORAL CHANGES IN A MOUSE RESTRAINT STRESS MODEL
Authors: Shimbori C , Khalil A , Kraimi N , Lu J , De Palma G , Hapfelmeier S , Collins S , Bercik P 
Published: February 2025

Abstract

Background
Bacterial translocation is defined as migration of bacteria or bacterial fragments from the intestinal lumen into extraintestinal tissues; this process has been implicated in the pathophysiology of gastrointestinal disorders and central nervous system disorders. However, the direct causal relationship between bacterial translocation and behavioral changes, as well as the mechanism of bacterial translocation remains unclear. In the previous study, we showed that commensal microbes can cross the intestinal barrier and access deeper layers of the gut and distal organs in the restraint stress model. In this study, we further investigated whether bacterial translocation contribute to behavioral changes in a mouse restraint stress model using invasive bacteria.

Aims
To investigate whether invasive bacteria can translocate and exacerbate behavioral alterations in a stress model.

Methods
SPF C57BL/6 mice were assigned to either the restraint stress group or the non-stress control group. Each group was further divided into two subgroups: one receiving a vehicle and the other inoculated with auxotrophic Salmonella enterica serovar Typhimurium HA630 via oral gavage three times per week during the stress period (n=6-14 per group). In a separate experiment, stressed and non-stressed mice were each split into 2 groups: vehicle or GFP-Salmonella; inoculated with GFP labeled wild type Salmonella enterica serovar typhimurium via single oral gavaging (n=6-7). After the last session of stress, we conducted light/dark preference and tail suspension tests. We collected jejunum, colon, myenteric lymph node, liver, spleen, and brain samples for histology and performed iterative bleaching extends multiplexity (IBEX) staining. We also sampled blood, liver, spleen, and brain for bacterial cultures under aseptic conditions.

Results
Transient salmonella inoculation enhanced stress-induced anxiety-like behaviour accompanied by higher rate of bacterial translocation. Histology analysis showed that intestinal bacteria were invade into the intestinal mucosa and co-localized with goblet cells in jejunum, and colon, and some of them were in close proximity with neurons in stress group. Interestingly, some bacteria appeared to be within the CD103+ cells in the colon, as well as in the hippocampus. GFP-salmonella inoculation enhanced stress-induced depression-like behaviour accompanied by higher rate of bacterial translocation.

Conclusions
This study indicates that intestinal bacteria translocation could contribute to the stress-induced behaviors. Our histology data suggest potential contribution of goblet and CD103+ cells in gut bacterial translocation in the restrained stress model.

Funding Agencies
CAG, CIHR
A26 PROFILE OF ACTIVATED B-CELL EXPANSION IN THE DISTAL COLON AND MESENTERIC LYMPH NODES OF COLITIC MICE
Authors: Sabzevary-Ghahfarokhi M , Marshall A , Ghia J 
Published: February 2025

Abstract

Background
Gut B cells maintain homeostasis by producing IgA antibodies that control the entry of commensal bacteria and pathogens. An increase in the number of B cells in the inflamed colon was detected in ulcerative colitis (UC) patients. Pro-inflammatory IgG antibodies binding to commensal bacteria are significantly elevated in UC, promoting intestinal inflammation.

Aims
To determine the effects of intestinal inflammation on the B cell compartment using a preclinical model of UC.

Methods
32 CD-1 WT males were treated for 6 days with 2.5% (w/v) dextran sulfate sodium (DSS), followed by 8 days of recovery (regular water). Disease activity index was monitored daily. Distal colonic mRNA expression of cytokine (tumor necrosis [TNF-α], B-cell activating factor [Baff]) and factors associated with B cell attraction (chemokine (C-X-C motif) ligand [CXCL]13) were assessed by qRT-PCR. Localization using B cells phenotype (B220, cluster of differentiation (CD) 19, CD138, GL7, and IgD) and activation markers (CD80 & CD86) were assessed by flow cytometry and immunofluorescence (IF) in Peyers’ patches, distal colon, and mesenteric lymph nodes (MLN). Levels of IgA, M, G1, G2b, and G2c in colon tissue and serum were determined by ELISA.

Results
In colitic mice, TNF-α, Baff, and CXCL-13 mRNA expression was significantly upregulated, and immunostaining demonstrated several aggregated sites of B cells with the phenotype of B220+, IgD+, and CD19+in the lamina propria. Aggregated B cells were positive for co-expression of IgD and CD19 markers and negative for expression of IgA and IgG antibodies. Flow cytometry data showed a significant increase in the percentage of B220+ and CD19+ B cells within the CD45+ live cell population in colitic mice’s distal colon and MLNs. In addition, in colitic mice, the percentage of B cells expressing CD86 significantly increased in the distal colon, Peyers’ patches, and MLN. Furthermore, in colitic conditions, the percentage of B cells producing IgG1 was increased in the Peyers’ patches and distal part of the colon but only in Peyers’ patches for IgA-producing B cells. In colitic mice, IgA/IgG2c ratio in colon tissue decreased, and serum IgG2b, IgG2c, and IgG1 antibody levels increased, with no difference for IgA and IgM.

Conclusions
Inflammatory conditions lead to B cell activation and recruitment with aggregated naïve B cells in the lamina propria that don’t switch to IgG or IgA. In colitis, systemic IgG subtypes increase, while Peyer’s patches may actively produce B cells expressing IgA or IgG1 during intestinal inflammation. These findings may guide the development of new UC therapies.

Funding Agencies
CCC
A28 PROFILE OF ACTIVATED B-CELL EXPANSION IN THE DISTAL COLON AND MESENTERIC LYMPH NODES OF COLITIC MICE
Authors: Sabzevary-Ghahfarokhi M , Marshall A , Ghia J 
Published: February 2025

Abstract

Background
Gut B cells maintain homeostasis by producing IgA antibodies that control the entry of commensal bacteria and pathogens. An increase in the number of B cells in the inflamed colon was detected in ulcerative colitis (UC) patients. Pro-inflammatory IgG antibodies binding to commensal bacteria are significantly elevated in UC, promoting intestinal inflammation.

Aims
To determine the effects of intestinal inflammation on the B cell compartment using a preclinical model of UC.

Methods
32 CD-1 WT males were treated for 6 days with 2.5% (w/v) dextran sulfate sodium (DSS), followed by 8 days of recovery (regular water). Disease activity index was monitored daily. Distal colonic mRNA expression of cytokine (tumor necrosis [TNF-α], B-cell activating factor [Baff]) and factors associated with B cell attraction (chemokine (C-X-C motif) ligand [CXCL]13) were assessed by qRT-PCR. Localization using B cells phenotype (B220, cluster of differentiation (CD) 19, CD138, GL7, and IgD) and activation markers (CD80 & CD86) were assessed by flow cytometry and immunofluorescence (IF) in Peyers’ patches, distal colon, and mesenteric lymph nodes (MLN). Levels of IgA, M, G1, G2b, and G2c in colon tissue and serum were determined by ELISA.

Results
In colitic mice, TNF-α, Baff, and CXCL-13 mRNA expression was significantly upregulated, and immunostaining demonstrated several aggregated sites of B cells with the phenotype of B220+, IgD+, and CD19+in the lamina propria. Aggregated B cells were positive for co-expression of IgD and CD19 markers and negative for expression of IgA and IgG antibodies. Flow cytometry data showed a significant increase in the percentage of B220+ and CD19+ B cells within the CD45+ live cell population in colitic mice’s distal colon and MLNs. In addition, in colitic mice, the percentage of B cells expressing CD86 significantly increased in the distal colon, Peyers’ patches, and MLN. Furthermore, in colitic conditions, the percentage of B cells producing IgG1 was increased in the Peyers’ patches and distal part of the colon but only in Peyers’ patches for IgA-producing B cells. In colitic mice, IgA/IgG2c ratio in colon tissue decreased, and serum IgG2b, IgG2c, and IgG1 antibody levels increased, with no difference for IgA and IgM.

Conclusions
Inflammatory conditions lead to B cell activation and recruitment with aggregated naïve B cells in the lamina propria that don’t switch to IgG or IgA. In colitis, systemic IgG subtypes increase, while Peyer’s patches may actively produce B cells expressing IgA or IgG1 during intestinal inflammation. These findings may guide the development of new UC therapies.
Funding Agencies:
A30 THROUGH-THE-SCOPE CLIP WITH ANCHOR PRONGS FOR PROPHYLACTIC CLIP CLOSURE AFTER GI LESION RESECTION: A PROSPECTIVE COHORT STUDY
Authors: von Renteln D , Rex D , Pohl H , Kumta N , Chan S , Ryou M , Zaheer N , Zhou P H , Inoue H , Peetermans J , Rousseau M , Mosko J 
Published: February 2025

Abstract

Background
Endoscopic clipping following gastrointestinal (GI) lesion resection provides prophylaxis for delayed bleeding. A rotatable, anchor-pronged through-the-scope endoscopic clip (TTSC) underwent limited prospective study since commercialization in the USA in 2022.

Aims
We prospectively studied 30-day delayed bleeding rates after prophylactic clip closure of lesions using the new TTSC.

Methods
We conducted a multicenter, prospective cohort study of the anchor-pronged MANTISTM clip (Boston Scientific Corporation, Marlborough, Massachusetts, USA) used for prophylactic clipping after lesion resection at 10 sites in 6 countries (ClinicalTrials.gov number, NCT05653843). Outcomes were 1) complete defect closure without delayed bleeding at the original resection site, 2) rate of delayed bleeding at the original resection site, defined as a severe bleeding event requiring hospitalization, blood transfusion (&gt;5 units), or another invasive intervention ≤30 days after study clip placement, 3) rate of serious device or procedure-related adverse events (SAEs).

Results
Among 191 enrolled participants, the mean age was 65.4±12.2 (range 23-89) years, and 110 (57.6%) were male. Median maximum lesion diameter was 25.0 (range 5.0-100.0) mm. Of 199 attempted clipping procedures, 190 (95.5%) defects had complete closure without delayed bleeding at the original lesion site (Table). Delayed bleeding occurred in 1 (0.5%) patient by 30 days after the index procedure. Seven (3.7%) patients had at least one SAE, including bleeding (2 patients), perforation (1), aspiration (1), nausea (1), pneumoperitoneum (1), postpolypectomy syndrome (1). No SAEs were considered device-related.

Conclusions
A rotatable, anchor-pronged TTSC showed high rates of procedural completion and sustained lesion closure, and low rates of delayed bleeding or other SAEs by 30 days after the index procedure.
Table. Main outcomes (N=199 lesions in 191 patients)

*Bleeding SAEs within 7 days were counted as failures of the primary efficacy endpoint.

Funding Agencies
Boston Scientific Corporation