Motivation to participate and attrition factors in a COVID-19 biobank: A qualitative study

BACKGROUND

The Biobanque québécoise de la COVID-19 (Quebec Biobank for COVID-19, or BQC19) is a provincial initiative that aims to manage the longitudinal collection, storage, and sharing of biological samples and clinical data related to COVID-19. During the study, BQC19 investigators reported a high loss-to-follow-up rate. The current study aimed to explore motivational and attrition factors from the perspective of BQC19 participants and health care and research professionals.

METHODS

This was an inductive exploratory qualitative study. Using a theoretical sampling approach, a sample of BQC19 participants and professionals were invited to participate via semi-structured interviews. Topics included motivations to participate; participants' fears, doubts, and barriers to participation; and professionals' experiences with biobanking during the COVID-19 pandemic.

RESULTS

Interviews were conducted with BQC19 participants (n = 23) and professionals (n = 17) from 8 clinical data collection sites. Motivations included the contribution to science and society in crisis, self-worth, and interactions with medical professionals. Reasons for attrition included logistical barriers, negative attitudes about public health measures or genomic studies, fear of clinical settings, and a desire to move on from COVID-19. Motivations and barriers seemed to evolve over time and with COVID-19 trends and surges. Certain situations were associated with attrition, such as when patients experienced indirect verbal consent during hospitalization. Barriers related to human and material resources and containment/prevention measures limited the ability of research teams to recruit and retain participants, especially in the ever-evolving context of crisis.

CONCLUSION

The pandemic setting impacted participation and attrition, either by influencing participants' motivations and barriers or by affecting research teams' ability to recruit and retain participants. Longitudinal and/or biobanking studies in a public health crisis setting should consider these factors to limit attrition.

Bacterial Biomarkers of the Oropharyngeal and Oral Cavity during SARS-CoV-2 Infection

(1) Background: Individuals with COVID-19 display different forms of disease severity and the upper respiratory tract microbiome has been suggested to play a crucial role in the development of its symptoms. (2) Methods: The present study analyzed the microbial profiles of the oral cavity and oropharynx of 182 COVID-19 patients compared to 75 unaffected individuals. The samples were obtained from gargle screening samples. 16S rRNA amplicon sequencing was applied to analyze the samples. (3) Results: The present study shows that SARS-CoV-2 infection induced significant differences in bacterial community assemblages, with Prevotella and Veillonella as biomarkers for positive-tested people and Streptococcus and Actinomyces for negative-tested people. It also suggests a state of dysbiosis on the part of the infected individuals due to significant differences in the bacterial community in favor of a microbiome richer in opportunistic pathogens. (4) Conclusions: SARS-CoV-2 infection induces dysbiosis in the upper respiratory tract. The identification of these opportunistic pathogenic biomarkers could be a new screening and prevention tool for people with prior dysbiosis.

Arctic bacterial diversity and connectivity in the coastal margin of the Last Ice Area

Arctic climate change is leading to sea-ice attrition in the Last Ice Area along the northern coast of Canada and Greenland, but less attention has been given to the associated land-based ecosystems. Here we evaluated bacterial community structure in a hydrologically coupled cryo-ecosystem in the region: Thores Glacier, proglacial Thores Lake, and its outlet to the sea. Deep amplicon sequencing revealed that Polaromonas was ubiquitous, but differed genetically among diverse niches. Surface glacier-ice was dominated by Cyanobacteria, while the perennially ice-capped, well-mixed water column of Thores Lake had a unique assemblage of Chloroflexi, Actinobacteriota, and Planctomycetota. Species richness increased downstream, but glacier microbes were little detected in the lake, suggesting strong taxonomic sorting. Ongoing climate change and the retreat of Thores Glacier would lead to complete drainage and loss of the lake microbial ecosystem, indicating the extreme vulnerability of diverse cryohabitats and unique microbiomes in the Last Ice coastal margin.

Adapting Transportation Planning e-Tools to Older Adults' Needs: Scoping Review

BACKGROUND

Aging is often accompanied by a decrease in physical and sensory capacities and financial resources, which makes travel and the use of public transport a big challenge for older adults. These mobility limitations may prevent them from going out for groceries, medical appointments, or entertainment, which increases the risk of social isolation. A key element in helping older adults to maintain healthy aging and social engagement is to foster autonomy, freedom, and active mobility. A transportation planning e-tool can provide older adults with information about transport and trip options. There are many transportation planning e-tools, but little is known about whether and how their characteristics and functionalities address older adults' needs and preferences.

OBJECTIVE

This study aims to map existing transportation e-tools and identify gaps to be filled in order to match their functionalities with older adults' needs and preferences.

METHODS

A scoping review of existing transportation planning e-tools was conducted based on the approach developed by Arksey and O'Malley. A search in the scientific literature (Academic Search Complete, MEDLINE, CINAHL, SocINDEX, and ERIC) as well as gray literature (TRID Database, Google Scholar, Proquest, Google Play, etc) was conducted in June 2020 and updated 3 times; in September 2021, December 2021, and May 2022. After the studies were selected, a comparative analysis was performed by 2 evaluators; an occupational therapy student and a computer science student. These e-tools were analyzed with respect to some characteristics (eg, tool's development status, target customers, and geographic coverage) as well as 10 functionalities (time autonomy, walkability, crowd avoidance, incline avoidance, weather consideration, dark avoidance, winter obstacles avoidance, amenities inclusion, taxi driver's information, and support affordance) that we defined based on older adults' needs and preferences (mainly Canadians). These needs were identified from a literature review and confirmed by workshops (focus groups).

RESULTS

The scientific and gray literature search yielded 463 sources, and 42 transportation e-tools were included. None of the e-tools reviewed addresses all 10 functionalities. More specifically, functionalities such as dark avoidance and support affordance were not addressed by any of the included e-tools.

CONCLUSIONS

Most of the e-tools currently available to plan trips do not address older adults' needs and preferences. The results of this scoping review helped fill this gap by identifying functionalities to include in transportation planning e-tools designed to promote active aging. The findings of this study highlight the need to use a multicriteria optimization algorithm to address older adults' mobility needs and preferences.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.2196/33894.

A203 EARLY PROACTIVE DRUG MONITORING STRATEGY OF INFLIXIMAB AS MONOTHERAPY FOR INFLAMMATORY BOWEL DISEASE IN PAEDIATRIC PATIENTS IS ASSOCIATED WITH GOOD SUSTAINED CLINICAL REMISSION

Background

Monotherapy with Infliximab (IFX) can be as efficient as combotherapy with immunomodulators in the treatment and maintenance of remission for children with inflammatory bowel disease (IBD) if an early proactive therapeutic drug monitoring strategy is adequately performed. This strategy may allow optimization of blood levels of IFX in order to obtain a sustained clinical response.

Purpose

This study demonstrated that with appropriate early trough levels of IFX before dose #3 and dose #4 , monotherapy was very efficient in inducing remssion at week 52 .

Method

A retrospective study was conducted at CHU Sainte-Justine, Montréal,Canada .Children with IBD 2 to 18 years old diagnosed between 01/2018 and 06/2020 and treated with IFX less than 30 days after diagnosis were included .IFX blood levels were collected before the 3rd and/or 4th dose of IFX and regularly thereafter. Adjustments were done in IFX dose per infusion according to blood levels and clinical response. The primary outcome was clinical remission at one year after diagnosis.The secondary outcomes included: (1) At 52 weeks, the median (IQR) dose of IFX (mg/kg) and the intervals between IFX infusions ; (2) the median (IQR) number of IFX dose changes and the median (IQR) number of blood trough levels of IFX done.

Result(s)

101 patients were included : 56.4% males; 81CD; 18 UC; 2 IBDU. Mean age at diagnosis was 13.2 years (IQR = 11.20 to 15. 20).

Median time to IFX initiation after diagnosis was 5 days (IQR :3-14).Median IFX dose #1: was 8.4 mg/kg (IQR = 5. 8 to 10).

90% of patient had an IFX optimisation (increasing dose and/or shortening intervals) after dose 3 or dose 4. At week 52, 36,5% of patients were receiving IFX infusion every 4 weeks and 30,6% every 6 weeks. The median IFX dose per infusion was 8,9mg/kg (IQR = 7.4- 9,8 ). The IFX doses at week 52 varied greatly according to age at diagnosis The median number of IFX blood level dosage was 4 per patient over a year (IQR=3-5).At week 52, 83 patients (84.6%) achieved clinical remission with a median IFX level of 10.96 (7.05-15.59). 74 /83 (89%) were on monotherapy and 9/83(10.8%) on combotherapy

Image

Conclusion(s)

Early treatment for IBD with IFX as monotherapy and an early proactive optimization strategy is associated with a good sustained steroid free clinical remissionAt week 52, 83 patients (84.6%) achieved clinical remission with a median IFX level of 10.96 (7.05-15.59). 74 /83 (89%) were on monotherapy and 9/83(10.8%) on combotherapy.The majority of the patients required IFX optimization during their first year of treatment. We therefore recommend to proactively monitor blood levels of IFX before the third and fourth dose of IFX and thereafter, in order to lower the risk of treatment failure and anti-infliximab antibodies occurrence.

Please acknowledge all funding agencies by checking the applicable boxes below

None

Disclosure of Interest

C. Girard: None Declared, S. Ackhar: None Declared, S. Sassine: None Declared, L. Chapuy: None Declared, P. Jantchou: None Declared, C. Deslandres Speakers bureau of: moderator and speaker Abbvie and Janssen

A Tale of Two Seasons: Distinct Seasonal Viral Communities in a Thermokarst Lake

Thermokarst lakes are important features of subarctic landscapes and are a substantial source of greenhouse gases, although the extent of gas produced varies seasonally. Microbial communities are responsible for the production of methane and CO₂ but the "top down" forces that influence microbial dynamics (i.e., grazers and viruses) and how they vary temporally within these lakes are still poorly understood. The aim of this study was to examine viral diversity over time to elucidate the seasonal structure of the viral communities in thermokarst lakes. We produced virus-enriched metagenomes from a subarctic peatland thermokarst lake in the summer and winter over three years. The vast majority of vOTUs assigned to viral families belonged to Caudovirales (Caudoviricetes), notably the morphological groups myovirus, siphovirus and podovirus. We identified two distinct communities: a dynamic, seasonal community in the oxygenated surface layer during the summer and a stable community found in the anoxic water layer at the bottom of the lake in summer and throughout much of the water column in winter. Comparison with other permafrost and northern lake metagenomes highlighted the distinct composition of viral communities in this permafrost thaw lake ecosystem.

Physical Activity Interventions in Rehabilitation Programs for Outpatients With Mild Traumatic Brain Injury

Introduction: There is limited scientific evidence about the optimal content and parameters of physical activity (PA) interventions for rehabilitation outpatients with persisting symptoms of a mild traumatic brain injury (mTBI). Clinicians have thus had to develop services based on their expertise, feasibility and patient needs. Objectives: This study aimed to document PA interventions delivered in specialized programs of a Canadian province offering outpatient rehabilitation services for individuals with persisting symptoms of mTBI to inform clinical intervention development and future research. Materials and methods: Cross-sectional study using an online survey containing 32 multiple choice and short open-ended questions to be answered by program administrators, with their clinical team's input. Content analysis and descriptive statistics were used. Results: Data from 94% of rehabilitation sites (n = 17) revealed that PA interventions are delivered to children (n = 4), adults (n = 15) and older adults (n = 5) with mTBI symptoms lasting ≥1 month to ≥1 year post injury. PA interventions aim to increase participation (n = 14), improve body functions (n = 9), manage persisting mTBI symptoms (n = 5) and improve self-management skills (n = 5) and knowledge (n = 4). Interventions include individual (n = 15) or group-based (n = 12) format, home-programs (n = 7), and teaching/education (n = 6). Most PA interventions include aerobic and resistance exercises. PA dosage parameters vary greatly. Conclusion: Clinical experts use multimodal interventions for rehabilitation program users that target improvement in body functions, participation and symptoms. The results can inform the development, enhancement and evaluation of PA interventions. Studies evaluating the effectiveness of these interventions for this clientele are warranted.

Temperature-driven heterochrony as a main evolutionary response to climate changes in conodonts

Can we predict the evolutionary response of organisms to climate changes? The direction of greatest intraspecific phenotypic variance is thought to correspond to an 'evolutionary line of least resistance', i.e. a taxon's phenotype is expected to evolve along that general direction, if not constrained otherwise. In particular, heterochrony, whereby the timing or rate of developmental processes are modified, has often been invoked to describe evolutionary trajectories and it may be advantageous to organisms when rapid adaptation is critical. Yet, to date, little is known empirically as to which covariation patterns, whether static allometry, as measured in adult forms only, or ontogenetic allometry, the basis for heterochrony, may be prevalent in what circumstances. Here, we quantify the morphology of segminiplanate conodont elements during two distinct time intervals separated by more than 130 Myr: the Devonian-Carboniferous boundary and the Carnian-Norian boundary (Late Triassic). We evidence that the corresponding species share similar patterns of intraspecific static allometry. Yet, during both crises, conodont evolution was decoupled from this common evolutionary line of least resistance. Instead, it followed heterochrony-like trajectories that furthermore appear as driven by ocean temperature. This may have implications for our interpretation of conodonts' and past marine ecosystems' response to environmental perturbations.

Exploring diet shifts and ecology in modern sharks using calcium isotopes and trace metal records of their teeth

Sharks occupy all living environments of the marine realm as well as some freshwater systems. They display varied and flexible feeding behaviours, but understanding their diet remains challenging due to their elusive ecology and the invasiveness of stomach content analyses in regard of their threatened status. As a potential alternative, we discuss the variability in δ44/42 Ca values recorded in the tooth enamel of size-graded individuals belonging to three species of large sharks with distinct diets (Isurus oxyrinchus, Hexanchus griseus and Carcharodon carcharias). The preliminary results highlight shifts in diet linked to ontogeny (I. oxyrinchus and H. griseus) and spatial distribution (C. carcharias) characterizing feeding behaviour in these species at individual and population level. These outcomes agree with the results of traditional stomach analyses supporting that nontraditional stable isotopes thus represent new perspectives for the study of modern and extinct shark ecology. In addition, for the first time, the Sr/Ca elemental ratios measured in H. griseus reflect sexual differences that could be interpreted in terms of spatial segregation or physiological heterogeneities.

Developing a One-Stop Platform Transportation Planning Service to Help Older Adults Move Around in Their Community Where, When, and How They Wish: Protocol for a Living Lab Study

Background

 Multiple mobility-related challenges frequently appear with aging. As a result, many older adults have difficulty getting around, to go, for example, to doctors’ appointments or leisure activities. Although various means of transportation are currently available, older adults do not necessarily use them, partly because they do not know which ones are adapted to their needs and preferences. To foster older adults’ autonomy and freedom in their decision-making about transportation, it is crucial to help them make informed decisions about the means that suit them best.

Objective

Our aim is to develop Mobilainés, a one-stop platform transportation planning service combining different transport modes and services to help older adults move around in their community where, when, and how they wish. More specifically, we aim to (1) define older adults’ mobility needs and preferences in order to conceptualize a one-stop platform; (2) cocreate a prototype of the one-stop platform; and (3) test the prototype with users in a real-life context.

Methods

This ongoing study uses a “Living Lab” co-design approach. This approach differs from traditional research on aging by facilitating intersectoral knowledge sharing and innovative solutions by and with older adults themselves. A steering committee of 8 stakeholders from the public, scientific, and private sectors, as well as older citizens, will meet quarterly throughout the study. The design comprises three phases, each with several iterative subphases. Phase 1 is exploration: through co-design workshops and literature reviews, members of the intersectoral committee will define older adults’ mobility needs and preferences to support the conceptualization of the one-stop platform. Phase 2 is experimentation: 4 personas will be produced that reflect the different needs and preferences of typical older adult end users of the platform; for development of a prototype, scenarios and mockups (static designs of the web application) will be created through co-design sessions with older adults (N=12) embodying these personas. Phase 3 is evaluation: we will test the usability of the prototype and document changes in mobility, such as the ability to move around satisfactorily and to participate in meaningful activities, by and with older adults (N=30) who use the prototype. The steering committee will identify ways to support the adoption, implementation, and scaling up of Mobilainés to ensure its sustainability. Qualitative and quantitative data will be triangulated according to each subphase objective.

Results

 The first phase began in September 2019. The study is scheduled for completion by mid-2023.

Conclusions

 This innovative transportation planning service will merge existing transportation options in one place. By meeting a wide variety of older adults’ needs and preferences, Mobilainés will help them feel comfortable and safe when moving around, which should increase their participation in meaningful activities and reduce the risk of social isolation.

International Registered Report Identifier (IRRID)

DERR1-10.2196/33894

POS1506-HPR SYSTEMATIC LITERATURE REVIEW TO INFORM THE EULAR TASK FORCE FOR RECOMMENDATIONS/POINTS TO CONSIDER FOR THE NON-PHARMACOLOGICAL MANAGEMENT OF SYSTEMIC LUPUS ERYTHEMATOSUS AND SYSTEMIC SCLEROSIS

Background

The heterogeneity and complexity of the chronic autoimmune diseases systemic lupus erythematosus (SLE) and systemic sclerosis (SSc) necessitate comprehensive person-centred management, including non-pharmacological approaches. Recommendations for non-pharmacological management are currently lacking.

Objectives

To perform a systematic literature review to inform the EULAR task force for recommendations/points to consider for the non-pharmacological management of adult patients with SLE and SSc. Among research questions formulated by the task force, we aimed at identifying (i) non-pharmacological interventions that have been evaluated and (ii) their target health domains or organ systems.

Methods

We searched the Medline, Embase, Web of Science Core Collection and CINAHL for articles published between January 2000 and June 2021. From the initial search (n=15,803), 2 researchers independently performed the article selection. Conflicts were discussed until consensus with 2 additional researchers. Subsequent data extraction from the selected articles was performed by 4 researchers, with an overarching guidance by 2 additional researchers. Risk of bias assessment was performed according to Joanna Briggs Institute Critical Appraisal Checklists.

Results

A total of 111 articles for SLE and 75 for SSc were selected for analysis.

Non-pharmacological interventions identified for SLE included physical exercise (n=34), psychological support (n=21), dietary therapy and nutrition (n=15), patient education and self-management (n=14), photoprotection (n=5), medication adherence interventions (n=5), complementary and alternative medicine (CAM) e.g., Chinese medicine (n=5), multidisciplinary care (n=4), and phototherapy/laser modalities (n=4).

Interventions identified for SSc included physical exercise e.g., hand, oral and general exercise (n=21), phototherapy/laser modalities or shockwave therapy (n=15), patient education and self-management (n=10), CAM (n=8), hand-bathing e.g., in paraffin (n=5), manual therapy e.g., osteopathic manipulative treatment (n=5), dietary therapy and nutrition (n=5), oral hygiene (n=2), hyperbaric oxygen or ozone therapy (n=2) and multidisciplinary care (n=2).

Target health domains and organ systems identified within SLE included (in descending order) (i) disease activity, (ii) health-related quality of life (HRQoL), (iii) depression/anxiety, (iv) fatigue, (v) organ damage, (vi) inflammatory markers, (vii) psychological stress, (viii) pain, (ix) body composition/anthropometry, and (x) aerobic capacity.

Intervention targets in SSc included (i) functional impairment e.g., hand mobility, (ii) skin sclerosis including microstomia, (iii) HRQoL, (iv) pain, (v) circulation e.g., Raynaud’s phenomena and telangiectasias, (vi) skin ulcers, (vii) oral hygiene, (viii) fatigue, (ix) digestion, and (x) depression/anxiety.

Conclusion

Physical exercise was a frequently researched non-pharmacological intervention within both SLE and SSc. While psychological support and dietary therapy/nutrition were frequently investigated in SLE, phototherapy modalities were common in SSc. Patient education and self-management was advocated in both SLE and SSc literature. HRQoL was a frequent target domain in both diseases; while disease activity and psychosocial domains emerged as important targets in SLE, functional impairment and skin-related aspects constituted predominant targets in SSc. Efficacy of interventions varied considerably across studies. Current evidence is limited by the overall small study populations, and the lack of large RCTs.

Table 1.

Studies categorised by design.

Study designSLESScMeta-analysis of RCTs51RCT (including long-term follow-up or post-hoc analysis)4128Non-randomised longitudinal controlled/cohort studies287Retrospective cohort study, cross-sectional or case-control study162Case series or open pilot studies2137

Acknowledgements

The authors would like to thank the members of the EULAR task force for recommendations/points to consider for the non-pharmacological management of systemic lupus erythematosus and systemic sclerosis (in alphabetical order by family name) i.e., Helene Alexanderson, Laurent Arnaud, Oliver Distler, Andrea Domján, Els van den Ende, Kim Fligelstone, Agnes Kocher, Maddalena Larosa, Martin Lau, Alexandros Mitropoulos, Mwidimi Ndosi, Gunilla von Perner, Janet Poole, Anthony Redmond, Valentin Ritschl, Yvonne Sjöberg, Tillmann Uhlig, Cecília Varjú, Joke Vriezekolk, Elisabet Welin, and Rene Westhovens, for their contribution to the formulation of the research questions together with IP, CG, TS and CB.

Disclosure of Interests

None declared

Palmoplantar pustulosis and acrodermatitis continua of Hallopeau: demographical and clinical comparative study in a large multicentre cohort

Background

Acral pustular disease within the pustular psoriasis/psoriasis‐like spectrum mainly includes palmoplantar pustulosis (PPP) and acrodermatitis continua of Hallopeau (ACH). Scarce data argue for a distinction between these two entities, but no study has compared the clinical and epidemiologic characteristics of ACH and PPP.

Objectives

We aimed to perform a comparative description of the epidemiological and clinical characteristics of PPP and ACH in a multicentre retrospective cohort.

Methods

In this multicentre national retrospective cohort study, we compared the epidemiological characteristics, comorbidities and psoriasis characteristics of patients with PPP and ACH.

Results

A total of 234 patients were included: 203 (87%) with PPP, 18 (8%) with ACH and 13 (6%) with both, according to 2017 ERASPEN criteria. As compared with ACH, PPP was associated with female sex, smoking activity and higher median BMI (P = 0.01, P = 0.02 and P = 0.05 respectively). A family background of psoriasis was more frequent in PPP than ACH. Age of onset of palmoplantar disease was similar between PPP and ACH patients, median age 44 and 48 years respectively. Peripheral joint inflammatory involvement was the only rheumatic disease associated with ACH. The association with another psoriasis type was similar in PPP and ACH (57.6% and 61.1% respectively).

Conclusion

Our study confirms in a large PPP cohort the predominance of females and a high prevalence of smoking and elevated body mass index but also shows an association of these features in PPP as compared with ACH. In addition, it highlights peripheral arthritis as the only arthritis endotype associated with ACH. Increased knowledge of the immunogenetic backgrounds underlying these two entities is warranted to better stratify pustular psoriasis or psoriasis‐like entities for precision medicine.

French guidelines for the management of oral lichen planus (excluding pharmacological therapy)

INTRODUCTION

Oral lichen is a chronic inflammatory disease for which diagnostic management and follow-up are heterogeneous given the absence of specific guidelines in France. Our objective was to develop French multidisciplinary guidelines for the management of oral lichen.

MATERIALS AND METHODS

Working groups from the Groupe d'Etude de la Muqueuse Buccale (GEMUB) formulated a list of research questions and the corresponding recommendations according to the "formal consensus" method for developing practice guidelines. These recommendations were submitted to a group of experts and the degree of agreement for each recommendation was assessed by a scoring group.

RESULTS

Twenty-two research questions, divided into 3 themes (nosological classification and initial assessment, induced oral lichenoid lesions, and follow-up) resulted in 22 recommendations. Initial biopsy for histology is recommended in the absence of reticulated lesions. Biopsy for direct immunofluorescence is recommended for ulcerated, erosive, bullous types and for diffuse erythematous gingivitis. Management should include a periodontal and dental check-up, and investigation for extra-oral lesions. Hepatitis C testing is recommended only if risk factors are present. Definitions, triggering factors and the management of "induced oral lichenoid lesions" were clarified. Oral lichen must be monitored by a practitioner familiar with the disease at least once a year, using objective tools.

CONCLUSION

This formalised consensus of multidisciplinary experts provides clinical practice guidelines on the management and monitoring of oral lichen.

A186 CHANGES IN THE CLINICAL PHENOTYPE AND BEHAVIOR OF PEDIATRIC LUMINAL CROHN’S DISEASE AT DIAGNOSIS IN THE LAST DECADE

Background

Crohn’s disease (CD) triggers are incompletely understood and the incidence of the disease has been increasing.

Aims

The aims of this study were to describe the trends in the clinical, endoscopic, histological, and laboratory characteristics of pediatric CD during the last decade and to describe the seasonal variation of disease presentation at diagnosis.

Methods

Patients under 18 years old and diagnosed between 2009 and 2019 were included. Patients clinical, endoscopic, histological, and laboratory data were collected from the medical records. Data were analyzed for the cohort as a whole and according to diagnostic periods (2009–2014 and 2015–2019) and seasons.

Results

654 patients were included in the study. The total number of incident CD cases significantly increased yearly. Patients diagnosed between 2015 and 2019 were younger at diagnosis (OR: 2.30, p<0.0001), had more perianal diseases (OR= 2.30, p<0.001) and more intestinal biopsy granulomas (OR= 1.61, p=0.003) as compared to the 2009–2014 cohort. Also, there was a strong association between intestinal biopsy granulomas, young age at diagnosis and perianal fistulas or abscesses; the presence of granulomas was associated with greater perianal involvements (OR= 2.25, p<0.001) and younger age at diagnosis (OR = 0.90, p=0.0002). PCDAI and SES-CD scores at diagnosis, disease location and behavior and laboratory markers did not change over time.

There were fewer CD diagnosis during winter. The highest vitamin D levels in patients occurred in summer and fall, but the majority of patients had, regardless of the season of diagnosis, severe vitamin D deficiency (the median vitamin D level was 60.0 nmol/L in summer and fall compared to 47.0 nmol/L in winter-spring, p=0.003). Vitamin D levels at diagnosis are inversely correlated with PCDAI (Pearson correlation coefficient = -0.19, p=0.03) and SES-CD (-0.20, p=0.04). Patients diagnosed in fall had lower PCDAI and SES-CD scores, less failure to thrive, less digestive symptoms and less extensive digestive involvement. Colonic disease was significantly more frequent during summer and fall (27.3% of patients diagnosed in summer and fall versus 18.2% of cases in winter and spring, p=0.01).

Conclusions

The disease phenotype has changed over the years and there are important seasonal trends in the frequency and severety of the disease suggesting possible disease triggers. Our findings provide interesting avenues for future research, such as identifying the clinical significance of granulomas, vitamin D deficiency and microbiota on pediatric CD activity.

PCDAI at diagnosis according to the season.

Funding Agencies

NoneFonds Recherche Santé Québec / Fondation du CHU Sainte-Justine

A187 RISK FACTORS OF CLINICAL RELAPSES IN PEDIATRIC LUMINAL CROHN’S DISEASE, A RETROSPECTIVE COHORT STUDY

Background

Few risk factors are associated with the risk of relapses of Crohn’s disease in children.

Aims

The aims of this retrospective cohort study were to describe the rate of relapses in children with Crohn’s disease, its evolution over the past decade and to determine risk factors associated with relapse.

Methods

Patients under 18 years old and diagnosed between 2009 and 2019 were included. Patients clinical, endoscopic, histological, and laboratory characteristics, as well as their treatments, where collected from their medical records and the prospective CHU Sainte-Justine inflammatory bowel disease registry. Survival analyses and Cox regression models were used to assess the impact of those risk factors on relapse.

Results

639 patients were included. There was a decrease in the clinical relapse rate over the past decade: 70.9% of patients diagnosed between 2009 and 2014 experienced a relapse compared to 49.1% of patients diagnosed between 2015 and 2019 (p&lt;0.0001). The following variables were associated with clinical relapse: female sex (adjusted hazard ratio (aHR)= 1.51, p=0.0009), high PCDAI (aHR= 1.02, p=0.04) and SES-CD (aHR= 1.03, p=0.03) scores at diagnosis, upper digestive tract involvement (aHR= 1.59, p=0.0003), exposure to oral 5-ASA (aHR= 1.91, p=0.0003), use of immunomodulatory agents compared to TNF-alpha inhibitors (methotrexate aHR= 1.91, p=0.0006; thiopurines aHR= 2.06, p&lt;0.0001), presence of granulomas (aHR= 1.27, p=0.04) and increased eosinophils on intestinal biopsies (aHR= 1.34, p=0.02), high levels of C-reactive protein (aHR= 1.01, p&lt;0.0001) and fecal calprotectin (aHR=1.09, p&lt;0.0001) during clinical remission and low serum infliximab levels during maintenance (aHR for mean serum infliximab level under 7ug/mL = 2.48, p=0.005).

Conclusions

Relapse risk was significantly associated with baseline clinical, endoscopic, histological and laboratory data and treatment strategies. These results could help better select treatment options for pediatric Crohn’s disease at induction and maintenance.

Funding Agencies

NoneFonds Recherche Santé Québec / Fondation du CHU Sainte-Justine

A188 FACTORS ASSOCIATED WITH CLINICAL REMISSION IN PEDIATRIC LUMINAL CROHN’S DISEASE: A RETROSPECTIVE COHORT STUDY

Background

The natural evolution of Crohn’s disease is incompletely understood in the pediatric population. Data on factors influencing time-to-remission are very limited in the literature.

Aims

The aim of this retrospective cohort study was to describe the time to clinical remission in children with Crohn’s disease as well as changes over the past decade and to identify factors associated with time to clinical remission.

Methods

Patients under 18 years old diagnosed between 2009 and 2019 were included. All data were collected from the patients’ medical records and the CHU Sainte-Justine inflammatory bowel disease registry. Survival analyses and linear regression models were used to assess the impact of clinical, laboratory, endoscopic, histological and therapeutic factors on time to clinical remission.

Results

654 patients were included in the study. There was no change in the time to clinical remission over the past decade. Female sex in adolescents (ajusted bêta regression coefficient (aβ)= 31.8 days, p= 0.02), upper digestive tract involvement (aβ= 46.4 days, p= 0.04), perianal disease (aβ= 32.2 days, p= 0.04), presence of active inflammation on biopsies (aβ= 46.7 days, p= 0.01) and oral 5-ASA exposure (aβ=56.6 days, p= 0.002) were all associated with longer time to clinical remission. However, antibiotic exposure (aβ= -29.3 days, p=0.04), increased eosinophils on biopsies (aβ= -29.6 days, p=0.008) and combination of exclusive enteral nutrition and TNF- alpha inhibitors as induction therapy (aβ= -36.8, p=0.04) were associated with shorter time to clinical remission.

Conclusions

Time to clinical remission did not improve during the decade and was associated with baseline clinical and histological data and treatment strategies. Combination of enteral nutrition and TNF-alpha inhibitors was associated with faster clinical remission.

Funding Agencies

NoneFonds Recherche Santé Québec / Fondation du CHU Sainte-Justine

Local Habitat Filtering Shapes Microbial Community Structure in Four Closely Spaced Lakes in the High Arctic

Arctic lakes are experiencing increasingly shorter periods of ice cover due to accelerated warming at northern high latitudes. Given the control of ice cover thickness and duration over many limnological processes, these changes will have pervasive effects. However, due to their remote and extreme locations even first-order data on lake ecology is lacking for many ecosystems. The aim of this study was to characterize and compare the microbial communities of four closely spaced lakes in Stuckberry Valley (northern Ellesmere Island, Canadian Arctic Archipelago), in the coastal margin zone of the Last Ice Area, that differed in their physicochemical, morphological and catchment characteristics. We performed high-throughput amplicon sequencing of the V4 16S rRNA gene to provide inter- and intra-lake comparisons. Two deep (&gt;25 m) and mostly oxygenated lakes showed highly similar community assemblages that were distinct from those of two shallower lakes (&lt;10 m) with anoxic bottom waters. Proteobacteria, Verrucomicrobia, and Planctomycetes were the major phyla present in the four water bodies. One deep lake contained elevated proportions of Cyanobacteria and Thaumarchaeota that distinguished it from the others, while the shallow lakes had abundant communities of predatory bacteria, as well as microbes in their bottom waters that contribute to sulfur and methane cycles. Despite their proximity, our data suggest that local habitat filtering is the primary determinant of microbial diversity in these systems. This study provides the first detailed examination of the microbial assemblages of the Stuckberry lakes system, resulting in new insights into the microbial ecology of the High Arctic.

Differences in obstetrical care and outcomes associated with the proportion of the obstetrician's shift completed

BACKGROUND

Understanding and improving obstetrical quality and safety is an important goal of professional societies, and many interventions such as checklists, safety bundles, educational interventions, or other culture changes have been implemented to improve the quality of care provided to obstetrical patients. Although many factors contribute to delivery decisions, a reduced workload has addressed how provider issues such as fatigue or behaviors surrounding impending shift changes may influence the delivery mode and outcomes.

OBJECTIVE

The objective was to assess whether intrapartum obstetrical interventions and adverse outcomes differ based on the temporal proximity of the delivery to the attending's shift change.

STUDY DESIGN

This was a secondary analysis from a multicenter obstetrical cohort in which all patients with cephalic, singleton gestations who attempted vaginal birth were eligible for inclusion. The primary exposure used to quantify the relationship between the proximity of the provider to their shift change and a delivery intervention was the ratio of time from the most recent attending shift change to vaginal delivery or decision for cesarean delivery to the total length of the shift. Ratios were used to represent the proportion of time completed in the shift by normalizing for varying shift lengths. A sensitivity analysis restricted to patients who were delivered by physicians working 12-hour shifts was performed. Outcomes chosen included cesarean delivery, episiotomy, third- or fourth-degree perineal laceration, 5-minute Apgar score of <4, and neonatal intensive care unit admission. Chi-squared tests were used to evaluate outcomes based on the proportion of the attending's shift completed. Adjusted and unadjusted logistic models fitting a cubic spline (when indicated) were used to determine whether the frequency of outcomes throughout the shift occurred in a statistically significant, nonlinear pattern RESULTS: Of the 82,851 patients eligible for inclusion, 47,262 (57%) had ratio data available and constituted the analyzable sample. Deliveries were evenly distributed throughout shifts, with 50.6% taking place in the first half of shifts. There were no statistically significant differences in the frequency of cesarean delivery, episiotomy, third- or fourth-degree perineal lacerations, or 5-minute Apgar scores of <4 based on the proportion of the shift completed. The findings were unchanged when evaluated with a cubic spline in unadjusted and adjusted logistic models. Sensitivity analyses performed on the 22.2% of patients who were delivered by a physician completing a 12-hour shift showed similar findings. There was a small increase in the frequency of neonatal intensive care unit admissions with a greater proportion of the shift completed (adjusted P=.009), but the findings did not persist in the sensitivity analysis.

CONCLUSION

Clinically significant differences in obstetrical interventions and outcomes do not seem to exist based on the temporal proximity to the attending physician's shift change. Future work should attempt to directly study unit culture and provider fatigue to further investigate opportunities to improve obstetrical quality of care, and additional studies are needed to corroborate these findings in community settings.

Morphometric variance, evolutionary constraints and their change through time in Late Devonian Palmatolepis conodonts

Phenotypic variation is the raw material of evolution. Standing variation can facilitate response to selection along "lines of least evolutionary resistance", but selection itself might alter the structure of the variance. Shape was quantified using 2D geometric morphometrics in Palmatolepis conodonts through the Late Devonian period. Patterns of variance were characterized along the record by the variance-covariance matrix (P-matrix) and its first axis (Pmax). The Late Frasnian was marked by environmental oscillations culminating with the Frasnian/Famennian mass extinction. A shape response was associated with these fluctuations, together with a deflection of the Pmax and the P-matrix. Thereafter, along the Famennian, Palmatolepis mean shape shifted from broad elements with a large platform to slender elements devoid of platform. This shift in shape was associated with a reorientation of Pmax and the P-matrix, due to profound changes in the functioning of the elements selecting for new types of variants. Both cases provide empirical evidences that moving adaptive optimum can reorient phenotypic variation, boosting response to environmental changes. On such time scales, the question seems thus not to be whether the P-matrix is stable, but how it is varying in response to changes in selection regimes and shifts in adaptive optimum. This article is protected by copyright. All rights reserved.

[Granulomatous lung disease induced by kayexalate inhalation during immunotherapy for metastatic melanoma]

INTRODUCTION

When a patient treated by immune checkpoint inhibitors for metastatic melanoma presents with pulmonary symptoms, several diagnoses are possible. We report a case of acute granulomatous lung disease secondary to repeated kayexalate inhalations, and probably stimulated by immunotherapy.

CASE REPORT

A patient treated with pembrolizumab and then ipilimumab presented with fever and acute shortness of breath. His pulmonary symptoms got progressively worse, leading to an acute respiratory distress syndrome. Chest CT displayed a pattern of non-specific organized pneumonia. Pulmonary infection, tumor progression, specific immune-related lung toxicity and immunotherapy-induced sarcoidosis were discussed. Histopathological examination of a lung biopsy showed a foreign body granulomatous macrophage reaction associated with crystalline, basophilic, purple and laminated elements, evoking kayexalate particles. These elements helped rewrite the diagnosis and confirmed a kayexalate-induced granulomatous lung disease secondary to repeated aspiration. The patient's respiratory condition got better following discontinuation of kayexalate together with systemic corticosteroids. Symptoms relapsed with resumption of the immunotherapy but were controlled with the addition of a new course of prolonged systemic corticosteroid therapy. We can hypothesize that immunotherapy played a role in the recurrence of the granulomatous lung reaction, or that there was an association between an aspiration pneumonia and an immunotherapy-induced lung toxicity.

CONCLUSION

Facing respiratory symptoms during immunotherapy, the treatment may be the cause, but lung biopsy should be performed rapidly to arrive to a certain diagnosis.

Elevated rates of horizontal gene transfer in the industrialized human microbiome

Industrialization has impacted the human gut ecosystem, resulting in altered microbiome composition and diversity. Whether bacterial genomes may also adapt to the industrialization of their host populations remains largely unexplored. Here, we investigate the extent to which the rates and targets of horizontal gene transfer (HGT) vary across thousands of bacterial strains from 15 human populations spanning a range of industrialization. We show that HGTs have accumulated in the microbiome over recent host generations and that HGT occurs at high frequency within individuals. Comparison across human populations reveals that industrialized lifestyles are associated with higher HGT rates and that the functions of HGTs are related to the level of host industrialization. Our results suggest that gut bacteria continuously acquire new functionality based on host lifestyle and that high rates of HGT may be a recent development in human history linked to industrialization.

The outbreak of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2): A review of the current global status

There is currently an ongoing worldwide pandemic of a novel virus belonging to the family of Coronaviruses (CoVs) which are large, enveloped, plus-stranded RNA viruses. Coronaviruses belong to the order of Nidovirales, family of Coronavirinae and are divided into four genera: alphacoronavirus, betacoronavirus, gammacoronavirus and deltacoronavirus. CoVs cause diseases in a wide variety of birds and mammals and have been found in humans since 1960. To date, seven human CoVs were identified including the alpha-CoVs HCoVs-NL63 and HCoVs-229E and the beta-CoVs HCoVs-OC43, HCoVs-HKU1, the severe acute respiratory syndrome-CoV (SARS-CoV), the Middle East respiratory syndrome-CoV (MERS-CoV) and the novel virus that first appeared in December 2019 in Wuhan, China, and rapidly spread to 213 countries as of the writing this paper. It was officially named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by the international committee on taxonomy of viruses (ICTV) and the disease's name is COVID-19 for coronavirus disease 2019. SARS-CoV-2 is very contagious and is capable of spreading from human to human. Infection routes include droplet and contact, and aerosol transmission is currently under investigation. It is associated with a respiratory illness that may cause severe pneumonia and acute respiratory distress syndrome (ARDS). SARS-CoV-2 became an emergency of international concern. As of July 12, 2020, the virus has been responsible for 12,698,995 confirmed cases and 564,924 deaths worldwide and the number is still increasing. Up until now, no specific treatment has yet been proven effective against SARS-CoV-2. Since the beginning of this outbreak, several interesting papers on SARS-CoV-2 and COVID-19 have been published to report on the phylogenetic evolution, epidemiology, pathogenesis, transmission as well as clinical characteristics of COVID-19 and possible treatments agents. This paper is a systematic review of the available literature on SARS-CoV-2. It was performed in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) and aims to help readers access the latest knowledge surrounding this new infectious disease and to provide a reference for future studies.

Seasonal Regime Shift in the Viral Communities of a Permafrost Thaw Lake

Permafrost thaw lakes including thermokarst lakes and ponds are ubiquitous features of Subarctic and Arctic landscapes and are hotspots of microbial activity. Input of terrestrial organic matter into the planktonic microbial loop of these lakes may greatly amplify global greenhouse gas emissions. This microbial loop, dominated in the summer by aerobic microorganisms including phototrophs, is radically different in the winter, when metabolic processes shift to the anaerobic degradation of organic matter. Little is known about the viruses that infect these microbes, despite evidence that viruses can control microbial populations and influence biogeochemical cycling in other systems. Here, we present the results of a metagenomics-based study of viruses in the larger than 0.22 µm fraction across two seasons (summer and winter) in a permafrost thaw lake in Subarctic Canada. We uncovered 351 viral populations (vOTUs) in the surface waters of this lake, with diversity significantly greater during the summer. We also identified and characterized several phage genomes and prophages, which were mostly present in the summer. Finally, we compared the viral community of this waterbody to other habitats and found unexpected similarities with distant bog lakes in North America.

["Dys" disorders in health care training]

"Dys" disorders must be taken into account by trained teams in order for the people concerned to be able to undertake their training of choice. Learning is not easy, but neither is it impossible. With adapted support and a detailed analysis of the needs and tools required, it is possible to envisage working in the health care sector.

THU0393 INFLAMMATORY BOWEL DISEASES AMONG SECUKINUMAB-TREATED PATIENTS: 24 CASES FROM THE MISSIL REGISTRY

Background:

An alert regarding about the tolerance of Interleukin 17 (IL-17) inhibitors has been issued from data of randomized controlled trials showing cases of de novo inflammatory bowel diseases (IBD). In a recent analysis of pooled data from 21 clinical trials, cases of IBD events (including Crohn’s disease (CD), ulcerative colitis (UC) and inflammatory bowel disease unclassified (IBDU)) were uncommon (1). Yet, real-world data are lacking.

Objectives:

To describe real-world data about patients treated by IL-17 inhibitors developing new onset IBD (CD or UC).

Methods:

A French national registry called MISSIL was started in February 2018 to collect the cases of patients treated by IL-17 inhibitors developing new onset IBD. This registry is conducted by rheumatologist, dermatologist and gastroenterologist learned societies specialized on immune-mediated inflammatory diseases. In France, secukinumab (SEK) has been granted market authorization since June 2016 and ixekizumab since April 2018.

Results:

24 cases under SEK were reported between February 2018 and January 2020: 3 patients with psoriasis and 21 patients with spondylwoarthritis. There were 20 patients with new onset CD and 4 with UC. Mean age was 51.7 ± 15.7 years old and 12/24 were female; 10 presented an axial spondyloarthritis, 5 a peripheral spondyloarthritis and 6 both,13/17 were HLA-B27 positive,7/19 had a radiographic sacroiliitis and 11/17 a MRI sacroiliitis. Only 2 were biological Disease-modifying antirheumatic drug (bDMARD)-naïve. Crohn’s disease was mainly located at the ileum, colon and rectum. The median time to onset of symptoms was 2 (1-6) months. The main symptoms were diarrhea, nausea and vomiting and loss of weight. Median CRP at the onset of symptoms was 68 mg/L (41-140.5); 21 patients underwent biopsies, 12 were in favor of CD. IL-17 inhibitors were consistently stopped. Patients were treated by corticosteroids (16/24), mesalazine (7/24), methotrexate (3/24), thiopurines (2/24), infliximab (9/243), adalimumab (3/24), golimumab (2/24), ustekinumab (5/24). The evolution was favorable under treatment with complete resolution (4/24), improvement (11/24) or stabilization (5/24). 3 patients worsened under treatment and 1 died (massive myocardial infarction).

Conclusion:

IBD flare in patients treated with IL-17 inhibitors are rare and lead to discuss the potential iatrogenic role of IL-17 inhibitor drugs. Further cases are needed to better characterize this complication. A case-control study will be conducted to identify patients at risk to develop IBD under IL-17 inhibitor.

References:

[1]Reich et al. Incidence rates of inflammatory bowel disease in patients with psoriasis, psoriatic arthritis and ankylosing spondylitis treated with secukinumab: a retrospective analysis of pooled data from 21 clinical trials. Ann Rheum Dis. 2019;78:473-479

Disclosure of Interests:

Jean-Guillaume Letarouilly Grant/research support from: Research grant from Pfizer, Benjamin Pariente: None declared, Delphine Staumont-Sallé Speakers bureau: Lilly, Novartis, Philippe Goupille Grant/research support from: AbbVie, Amgen, Biogen, BMS, Celgene, Chugai, Lilly, Janssen, Medac, MSD France, Nordic Pharma, Novartis, Pfizer, Sanofi and UCB, Consultant of: AbbVie, Amgen, Biogen, BMS, Celgene, Chugai, Lilly, Janssen, Medac, MSD France, Nordic Pharma, Novartis, Pfizer, Sanofi and UCB, Speakers bureau: AbbVie, Amgen, Biogen, BMS, Celgene, Chugai, Lilly, Janssen, Medac, MSD France, Nordic Pharma, Novartis, Pfizer, Sanofi and UCB, Pascal Claudepierre Speakers bureau: Janssen, Novartis, Lilly, Stephane Varin: None declared, Sylvain Lanot: None declared, Emmanuelle Dernis Speakers bureau: Lilly, Novartis, Tristan Pascart Speakers bureau: Novartis, Lilly, Beatrice Banneville Speakers bureau: Lilly, Novartis, Pauline Baudart: None declared, Bruno Gombert: None declared, Elodie BAUER: None declared, Laurianne Plastaras: None declared, Sébastien Barbarot: None declared, Renaud FELTEN: None declared, Loïc Le Dantec: None declared, Nathalie Sultan-Bichat: None declared, Céline Girard: None declared, Arnaud Constantin Grant/research support from: Study was sponsored by Sanofi Genzyme, Consultant of: Consulting fees from Abbvie, BMS, Celgene, Gilead, Janssen, Lilly, Novartis, Pfizer, Roche, Sanofi, UCB, Daniel Wendling: None declared, Philippe Gaudin Speakers bureau: Lilly, Denis Jullien Speakers bureau: Lilly, Novartis, Thao Pham Speakers bureau: Novartis, Janssen, Lilly, Rene-Marc Flipo Speakers bureau: Novartis, Janssen, Lilly

Synthesis, evaluation and molecular modelling of piceatannol analogues as arginase inhibitors

Arginase is involved in a wide range of pathologies including cardiovascular diseases and infectious diseases whilst it is also a promising target to improve cancer immunotherapy. To date, only a limited number of inhibitors of arginase have been reported. Natural polyphenols, among them piceatannol, are moderate inhibitors of arginase. Herein, we report our efforts to investigate catechol binding by quantum chemistry and generate analogues of piceatannol. In this work, we synthesized a novel series of amino-polyphenols which were then evaluated as arginase inhibitors. Their structure-activity relationships were elucidated by deep quantum chemistry modelling. 4-((3,4-Dihydroxybenzyl)amino)benzene-1,2-diol 3t displays a mixed inhibition activity on bovine and human arginase I with IC50 (K i) values of 76 (82) μM and 89 μM, respectively.

[Use of rituximab in maintenance treatment of pemphigus: A retrospective series]

INTRODUCTION

Rituximab (RTX), currently recommended as first-line treatment in moderate to severe pemphigus vulgaris (PV) and superficial pemphigus (PS) along with initial systemic steroids, may also be used as second-line or subsequent treatment, and this therapeutic strategy was investigated in a real-life monocentre retrospective survey.

MATERIAL AND METHODS

All patients treated between January 2010 and March 2018 with RTX as second-line or subsequent treatment for moderate to severe PV or PS and followed for at least one year were included. The main objective was to evaluate rates and times of complete clinical remission (CCR) after a first course of RTX. The secondary objectives consisted mainly of treatment safety, and frequency and time to relapse after the initial CCR.

RESULTS

The 24 patients selected received on average 2 cycles of RTX (i.e. 24 initial cycles and 24 additional cycles in all) over a mean follow-up period of 45 months. 18/24 (75%) patients achieved initial CCR within a mean 7.7 months. Despite at least one relapse in 13/18 initially responding patients regardless of relapse time, 59% (14/24) and 33% (8/24) were either in CCR and off treatment, or in partial remission, whether treated or untreated, according to the latest patient news, with an overall response rate of 92%. Safety was fair in these fragile patients.

DISCUSSION AND CONCLUSION

This survey of the practical use of RTX confirms its interest in moderate to severe pemphigus as a second-line or subsequent treatment, a situation that probably remains relevant even if this molecule is increasingly used as first-line therapy.

Cancer cell-derived long pentraxin 3 (PTX3) promotes melanoma migration through a toll-like receptor 4 (TLR4)/NF-κB signaling pathway

Cutaneous melanoma is one of the most aggressive cancers characterized by a high plasticity, a propensity for metastasis, and drug resistance. Melanomas are composed of phenotypically diverse subpopulations of tumor cells with heterogeneous molecular profiles that reflect intrinsic invasive abilities. In an attempt to identify novel factors of the melanoma invasive cell state, we previously investigated the nature of the invasive secretome by using a comparative proteomic approach. Here, we have extended this analysis to show that PTX3, an acute phase inflammatory glycoprotein, is one such factor secreted by invasive melanoma to promote tumor cell invasiveness. Elevated PTX3 production was observed in the population of MITFlow invasive cells but not in the population of MITFhigh differentiated melanoma cells. Consistently, MITF knockdown increased PTX3 expression in MITFhigh proliferative and poorly invasive cells. High levels of PTX3 were found in tissues and blood of metastatic melanoma patients, and in BRAF inhibitor-resistant melanoma cells displaying a mesenchymal invasive MITFlow phenotype. Genetic silencing of PTX3 in invasive melanoma cells dramatically impaired migration and invasion in vitro and in experimental lung extravasation assay in xenografted mice. In contrast, addition of melanoma-derived or recombinant PTX3, or expression of PTX3 enhanced motility of low migratory cells. Mechanistically, autocrine production of PTX3 by melanoma cells triggered an IKK/NFκB signaling pathway that promotes migration, invasion, and expression of the EMT factor TWIST1. Finally, we found that TLR4 and MYD88 knockdown inhibited PTX3-induced melanoma cell migration, suggesting that PTX3 functions through a TLR4-dependent pathway. Our work reveals that tumor-derived PTX3 contributes to melanoma cell invasion via targetable inflammation-related pathways. In addition to providing new insights into the biology of melanoma invasive behavior, this study underscores the notion that secreted PTX3 represents a potential biomarker and therapeutic target in a subpopulation of MITFlow invasive and/or refractory melanoma.

Highlighting the potential of peer-led workshops in training early-career researchers for conducting research with Indigenous communities

For decades, Indigenous voices have called for more collaborative and inclusive research practices. Interest in community-collaborative research is consequently growing among university-based researchers in Canada. However, many researchers receive little formal training on how to collaboratively conduct research with Indigenous communities. This is particularly problematic for early-career researchers (ECRs) whose fieldwork often involves interacting with communities. To address this lack of training, two peer-led workshops for Canadian ECRs were organized in 2016 and 2017 with the following objectives: ( i) to cultivate awareness about Indigenous cultures, histories, and languages; ( ii) to promote sharing of Indigenous and non-Indigenous ways of knowing; and ( iii) to foster approaches and explore tools for conducting community-collaborative research. Here we present these peer-led Intercultural Indigenous Workshops and discuss workshop outcomes according to five themes: scope and interdisciplinarity, Indigenous representation, workshop environment, skillful moderation, and workshop outcomes. Although workshops cannot replace the invaluable experience gained through working directly with Indigenous communities, we show that peer-led workshops can be an effective way for ECRs to develop key skills for conducting meaningful collaborative research. Peer-led workshops are therefore an important but insufficient step toward more inclusive research paradigms in Canada.

Local fungi, willow and municipal compost effectively remediate petroleum-contaminated soil in the Canadian North

Low energy-input alternatives based on locally available products are needed for treating petroleum-hydrocarbon spills in northern regions. We tested the efficacy of three local biological components (municipal compost, white-rot fungus: Pleurotus ostreatus and willow: Salix planifolia) to remediate diesel-contaminated soils in a subarctic climate (Whitehorse, YT, Canada), and compared their efficacy to natural attenuation and chemical fertilizers (industry standard). After the first growing season, biologically amended treatments (BAT) that contained >2 biological components, had decreased 69-73% of the diesel's F2 fraction (C₁₀-C₁₆), which is more than natural attenuation or fertilizer (48 and 51%). By the third growing season, the BAT dropped below the Canadian Council of Ministers of the Environment's (CCME) Agricultural & Residential/Parkland guideline (<150 mg kg^-1) and 86% of willows had survived and developed extensive roots. MiSeq amplicon sequencing of fungal (ITS) and bacterial (16S) rRNA genes showed the BAT's microbial communities were significantly more abundant and diverse. We found 132 bacterial and 35 fungal genera unique to the BAT. Readily-available local biological components such as municipal compost, fungi and willows may provide an effective alternative to applications of imported chemical fertilizers for the bioremediation and revegetation of diesel-contaminated soil in northern environments.