259 results on '"D. Boucher"'
Search Results
2. Individual and environmental correlates of tap water consumption among adolescents in Canada.
- Author
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Vézina-Im LA, Beaulieu D, Turcotte S, Turcotte AF, Lessard L, Delisle-Martel J, Boucher D, Labbé V, and Gingras M
- Subjects
- Humans, Adolescent, Female, Male, Quebec, Surveys and Questionnaires, Drinking, Underage Drinking psychology, Underage Drinking statistics & numerical data, Adolescent Behavior psychology, Drinking Water
- Abstract
The study objective was to identify correlates of tap water consumption among adolescents. French-speaking adolescents from the province of Québec (Canada) were recruited in person and online from March to July 2023 using diverse recruitment strategies. Water consumption was measured using the validated French version of a questionnaire specifically designed to measure adolescents' beverage intake. Participants answered an online survey on their attitude towards tap and bottled water which also measured individual and environmental factors that can influence tap water consumption. A total of 218 adolescents (14-17 years; 55.5% female) completed the survey. On average, 79.2% of adolescents' water intake came from tap and 33.5% of them consumed exclusively tap water. Thinking that bottled water is more convenient than tap water was a significant correlate of adolescents' tap water consumption (OR = 0.70; 95% CI: 0.51, 0.95; p = 0.0219). Adolescents who believed that bottled water is more convenient than tap water were less likely to consume exclusively tap water. Public health interventions aimed at promoting adolescents' tap water should strive to make tap water intake be perceived as convenient as bottled water, such as encouraging teenagers to always carry along a reusable water bottle, installing drinking fountains in popular public areas, and increasing the visibility of such fountains., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Lydi-Anne Vezina-Im reports financial support was provided by the Centre intégré de santé et de services sociaux (CISSS) de Chaudière-Appalaches. Lydi-Anne Vezina-Im reports financial support was provided by the Fondation de l'Hôtel-Dieu de Lévis. Dominique Beaulieu reports financial support was provided by the Collectif de recherche sur la santé en région. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)
- Published
- 2024
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3. The development and validation of an investigator global assessment score for keratosis pilaris.
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Wang MA, Wilson A, Boucher D, Johal JS, Rosenthal NK, Cowan T, Koszegi B, Lara Rivero AD, Daniel BS, Martin LK, Kern JS, and Murrell DF
- Published
- 2024
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4. Inflammasomes in epithelial innate immunity: front line warriors.
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Robinson KS and Boucher D
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- Humans, Animals, Epithelium immunology, Epithelium metabolism, Epithelial Cells immunology, Epithelial Cells metabolism, Homeostasis immunology, Inflammasomes immunology, Inflammasomes metabolism, Immunity, Innate
- Abstract
Our epithelium represents a battle ground against a variety of insults including pathogens and danger signals. It encodes multiple sensors that detect and respond to such insults, playing an essential role in maintaining and defending tissue homeostasis. One key set of defense mechanisms is our inflammasomes which drive innate immune responses including, sensing and responding to pathogen attack, through the secretion of pro-inflammatory cytokines and cell death. Identification of physiologically relevant triggers for inflammasomes has greatly influenced our ability to decipher the mechanisms behind inflammasome activation. Furthermore, identification of patient mutations within inflammasome components implicates their involvement in a range of epithelial diseases. This review will focus on exploring the roles of inflammasomes in epithelial immunity and cover: the diversity and differential expression of inflammasome sensors amongst our epithelial barriers, their ability to sense local infection and damage and the contribution of the inflammasomes to epithelial homeostasis and disease., (© 2024 The Authors. FEBS Letters published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.)
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- 2024
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5. Outbreak of Highly Pathogenic Avian Influenza A(H5N1) Viruses in U.S. Dairy Cattle and Detection of Two Human Cases - United States, 2024.
- Author
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Garg S, Reed C, Davis CT, Uyeki TM, Behravesh CB, Kniss K, Budd A, Biggerstaff M, Adjemian J, Barnes JR, Kirby MK, Basler C, Szablewski CM, Richmond-Crum M, Burns E, Limbago B, Daskalakis DC, Armstrong K, Boucher D, Shimabukuro TT, Jhung MA, Olsen SJ, and Dugan V
- Subjects
- Animals, Cattle, Humans, Cattle Diseases epidemiology, United States epidemiology, Disease Outbreaks, Influenza A Virus, H5N1 Subtype isolation & purification, Influenza, Human epidemiology
- Abstract
Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. No potential conflicts of interest were disclosed.
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- 2024
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6. Fluorochrome-labeled inhibitors of caspase-1 require membrane permeabilization to efficiently access caspase-1 in macrophages.
- Author
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Thygesen SJ, Burgener SS, Mudai P, Monteleone M, Boucher D, Sagulenko V, Schroder K, and Stacey KJ
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- Animals, Mice, Mice, Knockout, Phosphate-Binding Proteins metabolism, Humans, Caspase 1 metabolism, Macrophages immunology, Macrophages metabolism, Cell Membrane Permeability drug effects, Fluorescent Dyes, Inflammasomes metabolism, Caspase Inhibitors pharmacology
- Abstract
Caspase-1 location in cells has been studied with fluorochrome-labeled inhibitors of caspase-1 (FLICA reagents). We report that FLICA reagents have limited cell-membrane permeability. This impacts experimental design as cells with intact membranes, including caspase-1 knockout cells, are not appropriate controls for cells with inflammasome-induced gasdermin D membrane pores., (© 2024 The Authors. European Journal of Immunology published by Wiley‐VCH GmbH.)
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- 2024
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7. Cooking at Home: Correlates of Frequency and Intention in Fifth Graders.
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Boucher D, Beaulieu D, and Simard D
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- Female, Child, Humans, Cooking, Regression Analysis, Surveys and Questionnaires, Intention, Attitude
- Abstract
Cooking at home is associated with health benefits, and 10- and 11-year-old children are capable of participating in meal preparation. However, opportunities for children to cook at home have declined. This study aimed to identify determinants of the frequency and the intention to cook at home in fifth graders using the Theory of Planned Behavior as a framework with quantitative methodology. A total of 241 participants across five elementary schools of the Chaudière-Appalaches region (Quebec, Canada) took part in this correlational study. Data were collected via a self-administered questionnaire based on the Theory of Planned Behavior. Regression analyses led to the identification of determinants of frequency and intention to cook at home. More than two-thirds of participants (69%) declared having cooked at home in the past 7 days. Intention was the only significant variable explaining 18% of the variance for frequency. Intention was determined by perceived behavioral control, attitude, descriptive norms, subjective norms, perceived barriers, being a girl, and normative beliefs, which explain 74% of the variance. Whereas other studies aiming at better understanding children's involvement in meal preparation at home focused on self-efficacy for cooking, this study highlights other behavioral determinants. For example, support from parents appears to be crucial to promote this behavior in this age group. Future research and interventions should be oriented toward determinants such as subjective norms and normative beliefs, and focus on children's autonomy., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
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- 2024
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8. Correction: Perinatal foodborne titanium dioxide exposure-mediated dysbiosis predisposes mice to develop colitis through life.
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Carlé C, Boucher D, Morelli L, Larue C, Ovtchinnikova E, Battut L, Boumessid K, Airaud M, Quaranta-Nicaise M, Ravanat JL, Dietrich G, Menard S, Eberl G, Barnich N, Mas E, Carriere M, Al Nabhani Z, and Barreau F
- Published
- 2024
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9. Extracorporeal Membrane Oxygenation-Dependent Fulminant Melioidosis From Caspase 4 Mutation Reversed by Interferon Gamma Therapy.
- Author
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Amali AA, Ravikumar S, Chew WL, Tan Z, Sam QH, Chen KW, Boucher D, MacLaren G, and Chai LYA
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- Humans, Interferon-gamma genetics, Mutation, Melioidosis drug therapy, Burkholderia pseudomallei genetics, Extracorporeal Membrane Oxygenation
- Abstract
We describe bedside-to-bench immunological and genetic elucidation of defective pyroptosis attributable to novel caspase 4 defect mediating pathogen-triggered inflammatory programmed cell death, in the setting of severe pneumonia and abscess-forming melioidosis in an overtly healthy host failing to clear Burkholderia pseudomallei infection, and how targeted adjunctive biological therapy led to a successful outcome., Competing Interests: Potential conflicts of interest. G. M. reports an unpaid role as President of the Extracorporeal Life Support Organization (ELSO). All other authors report no potential conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (© The Author(s) 2023. Published by Oxford University Press on behalf of Infectious Diseases Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
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- 2024
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10. NLRP12 interacts with NLRP3 to block the activation of the human NLRP3 inflammasome.
- Author
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Coombs JR, Zamoshnikova A, Holley CL, Maddugoda MP, Teo DET, Chauvin C, Poulin LF, Vitak N, Ross CM, Mellacheruvu M, Coll RC, Heinz LX, Burgener SS, Emming S, Chamaillard M, Boucher D, and Schroder K
- Subjects
- Animals, Humans, Mice, Adaptor Proteins, Signal Transducing, Intracellular Signaling Peptides and Proteins, Leukocytes, Mononuclear, NLR Family, Pyrin Domain-Containing 3 Protein, Syndrome, Hereditary Autoinflammatory Diseases, Inflammasomes
- Abstract
Inflammasomes are multiprotein complexes that drive inflammation and contribute to protective immunity against pathogens and immune pathology in autoinflammatory diseases. Inflammasomes assemble when an inflammasome scaffold protein senses an activating signal and forms a signaling platform with the inflammasome adaptor protein ASC. The NLRP subfamily of NOD-like receptors (NLRs) includes inflammasome nucleators (such as NLRP3) and also NLRP12, which is genetically linked to familial autoinflammatory disorders that resemble diseases caused by gain-of-function NLRP3 mutants that generate a hyperactive NLRP3 inflammasome. We performed a screen to identify ASC inflammasome-nucleating proteins among NLRs that have the canonical pyrin-NACHT-LRR domain structure. Only NLRP3 and NLRP6 could initiate ASC polymerization to form "specks," and NLRP12 failed to nucleate ASC polymerization. However, wild-type NLRP12 inhibited ASC inflammasome assembly induced by wild-type and gain-of-function mutant NLRP3, an effect not seen with disease-associated NLRP12 mutants. The capacity of NLRP12 to suppress NLRP3 inflammasome assembly was limited to human NLRP3 and was not observed for wild-type murine NLRP3. Furthermore, peripheral blood mononuclear cells from patients with an NLRP12 mutant-associated inflammatory disorder produced increased amounts of the inflammatory cytokine IL-1β in response to NLRP3 stimulation. Thus, our findings provide insights into NLRP12 biology and suggest that NLRP3 inhibitors in clinical trials for NLRP3-driven diseases may also be effective in treating NLRP12-associated autoinflammatory diseases.
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- 2024
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11. Targeting the COMMD4-H2B protein complex in lung cancer.
- Author
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Tang M, Burgess JT, Fisher M, Boucher D, Bolderson E, Gandhi NS, O'Byrne KJ, Richard DJ, and Suraweera A
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- Humans, Cell Line, Tumor, DNA Repair, Peptides genetics, Lung Neoplasms drug therapy, Lung Neoplasms genetics, Lung Neoplasms metabolism, Carcinoma, Non-Small-Cell Lung drug therapy, Carcinoma, Non-Small-Cell Lung genetics, Carcinoma, Non-Small-Cell Lung metabolism
- Abstract
Background: Lung cancer is the biggest cause of cancer-related deaths worldwide. Non-small cell lung cancer (NSCLC) accounts for 85-90% of all lung cancers. Identification of novel therapeutic targets are required as drug resistance impairs chemotherapy effectiveness. COMMD4 is a potential NSCLC therapeutic target. The aims of this study were to investigate the COMMD4-H2B binding pose and develop a short H2B peptide that disrupts the COMMD4-H2B interaction and mimics COMMD4 siRNA depletion., Methods: Molecular modelling, in vitro binding and site-directed mutagenesis were used to identify the COMMD4-H2B binding pose and develop a H2B peptide to inhibit the COMMD4-H2B interaction. Cell viability, DNA repair and mitotic catastrophe assays were performed to determine whether this peptide can specially kill NSCLC cells., Results: Based on the COMMD4-H2B binding pose, we have identified a H2B peptide that inhibits COMMD4-H2B by directly binding to COMMD4 on its H2B binding binding site, both in vitro and in vivo. Treatment of NSCLC cell lines with this peptide resulted in increased sensitivity to ionising radiation, increased DNA double-strand breaks and induction of mitotic catastrophe in NSCLC cell lines., Conclusions: Our data shows that COMMD4-H2B represents a novel potential NSCLC therapeutic target., (© 2023. The Author(s).)
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- 2023
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12. Perinatal foodborne titanium dioxide exposure-mediated dysbiosis predisposes mice to develop colitis through life.
- Author
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Carlé C, Boucher D, Morelli L, Larue C, Ovtchinnikova E, Battut L, Boumessid K, Airaud M, Quaranta-Nicaise M, Ravanat JL, Dietrich G, Menard S, Eberl G, Barnich N, Mas E, Carriere M, Al Nabhani Z, and Barreau F
- Subjects
- Pregnancy, Female, Animals, Mice, Dysbiosis chemically induced, Lactation, Mice, Inbred C57BL, Disease Models, Animal, Colitis chemically induced, Colitis genetics, Colitis metabolism, Inflammatory Bowel Diseases metabolism
- Abstract
Background: Perinatal exposure to titanium dioxide (TiO
2 ), as a foodborne particle, may influence the intestinal barrier function and the susceptibility to develop inflammatory bowel disease (IBD) later in life. Here, we investigate the impact of perinatal foodborne TiO2 exposure on the intestinal mucosal function and the susceptibility to develop IBD-associated colitis. Pregnant and lactating mother mice were exposed to TiO2 until pups weaning and the gut microbiota and intestinal barrier function of their offspring was assessed at day 30 post-birth (weaning) and at adult age (50 days). Epigenetic marks was studied by DNA methylation profile measuring the level of 5-methyl-2'-deoxycytosine (5-Me-dC) in DNA from colic epithelial cells. The susceptibility to develop IBD has been monitored using dextran-sulfate sodium (DSS)-induced colitis model. Germ-free mice were used to define whether microbial transfer influence the mucosal homeostasis and subsequent exacerbation of DSS-induced colitis., Results: In pregnant and lactating mice, foodborne TiO2 was able to translocate across the host barriers including gut, placenta and mammary gland to reach embryos and pups, respectively. This passage modified the chemical element composition of foetus, and spleen and liver of mothers and their offspring. We showed that perinatal exposure to TiO2 early in life alters the gut microbiota composition, increases the intestinal epithelial permeability and enhances the colonic cytokines and myosin light chain kinase expression. Moreover, perinatal exposure to TiO2 also modifies the abilities of intestinal stem cells to survive, grow and generate a functional epithelium. Maternal TiO2 exposure increases the susceptibility of offspring mice to develop severe DSS-induced colitis later in life. Finally, transfer of TiO2 -induced microbiota dysbiosis to pregnant germ-free mice affects the homeostasis of the intestinal mucosal barrier early in life and confers an increased susceptibility to develop colitis in adult offspring., Conclusions: Our findings indicate that foodborne TiO2 consumption during the perinatal period has negative long-lasting consequences on the development of the intestinal mucosal barrier toward higher colitis susceptibility. This demonstrates to which extent environmental factors influence the microbial-host interplay and impact the long-term mucosal homeostasis., (© 2023. The Author(s).)- Published
- 2023
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13. Validation d’un questionnaire mesurant la consommation de boissons sucrées, jus et eau auprès d’adolescents francophones.
- Author
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Vézina-Im LA Ph.D, Beaulieu D inf., Ph.D, Turcotte S M.Sc, Savard C inf., B.Sc, Lemieux S Dt.P., Ph.D, Boucher D inf., Ph.D, Gallani MC inf., Ph.D, and Paquette MC Dt.P., Ph.D
- Subjects
- Humans, Adolescent, Water, Beverages analysis, Surveys and Questionnaires, Energy Intake, Sugar-Sweetened Beverages
- Abstract
Purpose: To examine the temporal stability and relative validity of the adapted French version of an English self-reported questionnaire measuring the beverage intake (BEVQ) of adolescents. Methods: The French adaptation of the BEVQ (AF-BEVQ) included conversion from the imperial to the metric system and the adjustment of some formats to those available in Canada. Next, 60 adolescents from two regions in Quebec completed the AF-BEVQ and two web-based 24-hour dietary recalls (R24W) (one for a weekday and one for a weekend day) on two occasions, two weeks apart. Results: The AF-BEVQ had moderate intraclass correlation coefficients (ICC) for amounts of sugar-sweetened beverages (ICC: 0.68; 95% confidence interval [CI]: 0.46-0.81), fruit juice (ICC: 0.54; 95% CI: 0.23-0.72) and water (ICC: 0.66; 95% CI: 0.38-0.81) consumed. The amounts of sugar-sweetened beverages (r
s = 0.49; p < 0.0001), fruit juice (rs = 0.38; p = 0.0024) and water (rs = 0.65; p < 0.0001) reported in the AF-BEVQ were significantly correlated with those of both R24Ws. Conclusions: For the most part, the AF-BEVQ had adequate metrological properties. It is an interesting tool to quickly measure the sugar-sweetened beverage, fruit juice and water intake of French-speaking adolescents.- Published
- 2023
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14. Caspase-4 dimerisation and D289 auto-processing elicit an interleukin-1β-converting enzyme.
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Chan AH, Burgener SS, Vezyrgiannis K, Wang X, Acklam J, Von Pein JB, Pizzuto M, Labzin LI, Boucher D, and Schroder K
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- Animals, Humans, Mice, Caspase 1 metabolism, Interleukin-1beta metabolism, Intracellular Signaling Peptides and Proteins genetics, Intracellular Signaling Peptides and Proteins metabolism, Phosphate-Binding Proteins metabolism, Inflammasomes metabolism, NLR Family, Pyrin Domain-Containing 3 Protein genetics, NLR Family, Pyrin Domain-Containing 3 Protein metabolism, Caspases, Initiator metabolism, Gasdermins metabolism
- Abstract
The noncanonical inflammasome is a signalling complex critical for cell defence against cytosolic Gram-negative bacteria. A key step in the human noncanonical inflammasome pathway involves unleashing the proteolytic activity of caspase-4 within this complex. Caspase-4 induces inflammatory responses by cleaving gasdermin-D (GSDMD) to initiate pyroptosis; however, the molecular mechanisms that activate caspase-4 and govern its capacity to cleave substrates remain poorly defined. Caspase-11, the murine counterpart of caspase-4, acquires protease activity within the noncanonical inflammasome by forming a dimer that self-cleaves at D285 to cleave GSDMD. These cleavage events trigger signalling via the NLRP3-ASC-caspase-1 axis, leading to downstream cleavage of the pro-IL-1β cytokine precursor. Here, we show that caspase-4 first dimerises then self-cleaves at two sites-D270 and D289-in the interdomain linker to acquire full proteolytic activity, cleave GSDMD, and induce cell death. Surprisingly, caspase-4 dimerisation and self-cleavage at D289 generate a caspase-4 p34/p9 protease species that directly cleaves pro-IL-1β, resulting in its maturation and secretion independently of the NLRP3 inflammasome in primary human myeloid and epithelial cells. Our study thus elucidates the key molecular events that underpin signalling by the caspase-4 inflammasome and identifies IL-1β as a natural substrate of caspase-4., (© 2023 Chan et al.)
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- 2023
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15. Evaluation of a Depression Intervention in People With HIV and/or TB in Eswatini Primary Care Facilities: Implications for Southern Africa.
- Author
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Putnis N, Riches N, Nyamayaro A, Boucher D, King R, Walker IF, Burger A, Southworth P, Mwanjali V, and Walley J
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- Humans, Eswatini, Depression therapy, Africa, Southern, Primary Health Care, HIV Infections complications, HIV Infections therapy, HIV Infections diagnosis
- Abstract
Introduction: Depression associated with chronic illnesses is common in Southern Africa, yet there are major treatment gaps. This study assesses the feasibility and acceptability of the Healthy Activity Program intervention for depression among people with HIV and/or TB. The intervention involves training nonspecialist nurses in depression, including identification, counseling based on behavioral activation theory, and structured referral., Methods: This is a mixed methods evaluation of a pilot counseling service integrated within routine HIV and TB care from 2018 to 2019. Participants included people living with HIV and/or patients with TB in rural Eswatini., Results: A total of 324 people living with HIV and/or TB were screened for depression, with 19% (62/324) screening positive. The median number of sessions attended was 3 (interquartile range: 1-5), with 16/60 (26%) attending the minimum 5 sessions. Qualitative results indicated acceptability, but there were concerns about feasibility., Conclusions: The Healthy Activity Program is a promising option to manage the treatment gap for depression in people with HIV and/or TB. However, task-shifting to nonspecialist health care professionals without increasing staff capacity is a barrier to implementation. Realistic and pragmatic assessments of capacity and workforce are essential., (© Putnis et al.)
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- 2023
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16. The efficacy of adding oral sodium cromoglycate to stable treatment for controlling bullous pemphigoid-related pruritus: A retrospective study.
- Author
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Keller Rosenthal N, Boucher D, and Murrell DF
- Abstract
Introduction: Bullous pemphigoid (BP) is the most common autoimmune subepidermal blistering disease which mainly affects the elderly. It manifests as severe pruritus, urticarial plaques, and tense bullae and is associated with significant mortality. Therapy options for itch in BP patients are limited, mainly because the pathogenesis of itch in BP remains unclear. Sodium cromoglycate was commonly used in the past as an inhaled drug for the management of bronchial asthma and as an oral treatment for children with urticaria pigmentosa. In this study we sought to assess its efficacy in reducing BP associated itch., Objective: Assessing the efficacy of oral sodium cromoglycate in reducing BP-related pruritus after stabilization of disease activity., Methods: We retrospectively reviewed the medical records of patients with a confirmed diagnosis of BP who were treated with sodium cromoglycate. Patient reported outcome measures (PROM) including: BPDAI pruritus, ABQOL and TABQOL, and BPDAI activity score were compared at two points in time: before commencing treatment with sodium cromoglycate or before commencing maximal dose of this treatment, and at least 4 weeks after treatment commencement., Results: A total of 21 patients met the inclusion criteria. After at least 4 weeks of treatment with oral sodium cromoglycate BPDAI pruritus, ABQOL and TABQOL scores were statistically significantly decreased compared to the scores prior to treatment commencement, P < 0.000, P < 0.008, and P < 0.004, respectively., Discussion: Oral treatment with sodium cromoglycate for the management of pruritus in BP patients may be beneficial, however, further prospective studies are required to better assess its efficacy., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Keller Rosenthal, Boucher and Murrell.)
- Published
- 2022
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17. Phage Therapy Against Adherent-invasive E. coli: Towards a Promising Treatment of Crohn's Disease Patients?
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Boucher D and Barnich N
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- Mice, Animals, Escherichia coli, Intestinal Mucosa, Disease Models, Animal, Crohn Disease therapy, Phage Therapy, Bacteriophages, Colitis
- Published
- 2022
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18. Pre- and Postlicensure Animal Efficacy Studies Comparing Anthrax Antitoxins.
- Author
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Slay RM, Cook R, Hendricks K, Boucher D, and Merchlinsky M
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- Animals, Antigens, Bacterial, Exotoxins, Rabbits, Anthrax drug therapy, Anthrax prevention & control, Antitoxins therapeutic use, Bacillus anthracis
- Abstract
Background: The deliberate use of Bacillus anthracis spores is believed by the US government to be a high bioweapons threat. The first line of defense following potential exposure to B. anthracis spores would be postexposure prophylaxis with antimicrobials that have activity against B. anthracis. Additional therapies to address the effects of toxins may be needed in systemically ill individuals. Over the last 2 decades, the United States government (USG) collaborated with the private sector to develop, test, and stockpile 3 antitoxins: anthrax immunoglobulin intravenous (AIGIV), raxibacumab, and obiltoxaximab. All 3 products target protective antigen, a protein factor common to the 2 exotoxins released by B. anthracis, and hamper or block the toxins' effects and prevent or reduce pathogenesis. These antitoxins were approved for licensure by the United States Food and Drug Administration based on animal efficacy studies compared to placebo., Methods: We describe USG-sponsored pre- and postlicensure studies that compared efficacy of 3 antitoxins in a New Zealand White rabbit model of inhalation anthrax; survival following a lethal aerosolized dose of B. anthracis spores was the key measure of effectiveness. To model therapeutic intervention, intravenous treatments were started following onset of antigenemia., Results: In pre- and postlicensure studies, all 3 antitoxins were superior to placebo; in the postlicensure study, raxibacumab and obiltoxaximab were superior to AIGIV, but neither was superior to the other., Conclusions: These data illustrate the relative therapeutic benefit of the 3 antitoxins and provide a rationale to prioritize their deployment., (Published by Oxford University Press on behalf of Infectious Diseases Society of America 2022. This work is written by (a) US Government employee(s) and is in the public domain in the US.)
- Published
- 2022
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19. An introduction to the Marburg virus vaccine consortium, MARVAC.
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Cross RW, Longini IM, Becker S, Bok K, Boucher D, Carroll MW, Díaz JV, Dowling WE, Draghia-Akli R, Duworko JT, Dye JM, Egan MA, Fast P, Finan A, Finch C, Fleming TR, Fusco J, Geisbert TW, Griffiths A, Günther S, Hensley LE, Honko A, Hunegnaw R, Jakubik J, Ledgerwood J, Luhn K, Matassov D, Meshulam J, Nelson EV, Parks CL, Rustomjee R, Safronetz D, Schwartz LM, Smith D, Smock P, Sow Y, Spiropoulou CF, Sullivan NJ, Warfield KL, Wolfe D, Woolsey C, Zahn R, Henao-Restrepo AM, Muñoz-Fontela C, and Marzi A
- Subjects
- Animals, Humans, Marburg Virus Disease prevention & control, Marburgvirus, Viral Vaccines
- Abstract
The emergence of Marburg virus (MARV) in Guinea and Ghana triggered the assembly of the MARV vaccine "MARVAC" consortium representing leaders in the field of vaccine research and development aiming to facilitate a rapid response to this infectious disease threat. Here, we discuss current progress, challenges, and future directions for MARV vaccines., Competing Interests: T.W.G. holds U.S. patent number 7,635,485 issued to US Government, U.S. patent number 7,838,658 issued to Arbutus Biopharma, U.S. patent number 8,017,130 issued to US Government, U.S. patent number 8,716,464 issued to Arbutus Biopharma, and U.S. patent number 8,796,013 issued to Boston University. N.J.S. has a patent for Chimpanzee Adenoviral vector-based filovirus vaccines (for use in humans) with royalties paid to GlaxoSmithKline Biologicals. K.L.W. is a stockholder of Emergent BioSolutions. R.Z. holds a patent for “Methods and compositions for inducing protective immunity against Marburg virus infection”. All other authors declare no conflict of interest. The conclusions in this report are those of the authors and do not necessarily represent the official position of the U.S. Centers for Disease Control and Prevention.
- Published
- 2022
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20. Mathematical modelling of activation-induced heterogeneity in TNF, IL6, NOS2, and IL1β expression reveals cell state transitions underpinning macrophage responses to LPS.
- Author
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Dey S, Boucher D, Pitchford J, and Lagos D
- Abstract
Background: Despite extensive work on macrophage heterogeneity, the mechanisms driving activation induced heterogeneity (AIH) in macrophages remain poorly understood. Here, we aimed to develop mathematical models to explore theoretical cellular states underpinning the empirically observed responses of macrophages following lipopolysaccharide (LPS) challenge. Methods: We obtained empirical data following primary and secondary responses to LPS in two in vitro cellular models (bone marrow-derived macrophages or BMDMs, and RAW 264.7 cells) and single-cell protein measurements for four key inflammatory mediators: TNF, IL-6, pro-IL-1β, and NOS2, and used mathematical modelling to understand heterogeneity. Results: For these four factors, we showed that macrophage community AIH is dependent on LPS dose and that altered AIH kinetics in macrophages responding to a second LPS challenge underpin hypo-responsiveness to LPS. These empirical data can be explained by a mathematical three-state model including negative, positive, and non-responsive states (NRS), but they are also compatible with a four-state model that includes distinct reversibly NRS and non-responsive permanently states (NRPS). Our mathematical model, termed NoRM (Non-Responsive Macrophage) model identifies similarities and differences between BMDM and RAW 264.7 cell responses. In both cell types, transition rates between states in the NoRM model are distinct for each of the tested proteins and, crucially, macrophage hypo-responsiveness is underpinned by changes in transition rates to and from NRS. Conclusions: Overall, we provide a mathematical model for studying macrophage ecology and community dynamics that can be used to elucidate the role of phenotypically negative macrophage populations in AIH and, primary and secondary responses to LPS., Competing Interests: No competing interests were disclosed., (Copyright: © 2022 Dey S et al.)
- Published
- 2022
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21. Facteurs psychosociaux associés à l’intention de pratiquer régulièrement des activités physiques modérées chez les survivantes du cancer du sein.
- Author
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Lévesque-Gagné C and Boucher D
- Published
- 2022
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22. Psychosocial factors associated with the intention of breast cancer survivors to regularly practise moderate physical activity.
- Author
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Lévesque-Gagné C and Boucher D
- Abstract
Introduction: Regular physical activity (PA) can be beneficial to breast cancer survivors, although the majority do not devote sufficient time to the practice. The long-term side effects of cancer treatment represent barriers to adopting healthy lifestyle habits., Goal: Identify factors that influence the intention to practise regular PA among breast cancer survivors., Methodology: A correlational study was conducted among my Active Health (Ma Santé Active) program participants (N = 136), using a self-administered questionnaire based on the theory of planned behaviour., Findings: Multiple regression analysis shows that attitude, perceived control, behavioural beliefs and control beliefs are the determinants of intention., Discussion and Conclusion: It is recommended to design interventions based on these determinants to strengthen the behavioural intention of breast cancer survivors. The paper will also inform healthcare professionals about the intervention targets to be utilized to motivate women with a breast cancer diagnosis to engage in regular PA., (© 2022 Canadian Association of Nurses in Oncology (CANO).)
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- 2022
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23. Defoliation-induced changes in foliage quality may trigger broad-scale insect outbreaks.
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De Grandpré L, Marchand M, Kneeshaw DD, Paré D, Boucher D, Bourassa S, Gervais D, Simard M, Griffin JM, and Pureswaran DS
- Subjects
- Animals, Disease Outbreaks, Ecosystem, Insecta, Soil, Trees, Hemiptera, Moths
- Abstract
Top-down effects, like predation, are drivers of insect outbreaks, but bottom-up effects, like host nutritional quality, also influence outbreaks and could in turn be altered by insect-caused defoliation. We evaluated the prediction that herbivory leads to a positive feedback on outbreak severity as nutrient concentration in plant tissues increases through improved soil nutrient availability from frass and litter deposition. Over seven years of a spruce budworm outbreak, we quantified litter nutrient fluxes, soil nitrogen availability, and host tree foliar nutrient status along a forest susceptibility gradient. As the outbreak progressed, both soil nutrient fluxes and availability increased which, in turn, improved foliage quality in surviving host trees. This is consistent with boosted insect fitness and increased population density and defoliation as outbreaks grow. Our results suggest that a positive bottom-up feedback to forest ecosystems from defoliation may result in conditions favorable to self-amplifying population dynamics in insect herbivores that can contribute to driving broad-scale outbreaks., (© 2022. Crown.)
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- 2022
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24. Inflammatory Caspases: Toward a Unified Model for Caspase Activation by Inflammasomes.
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Ross C, Chan AH, von Pein JB, Maddugoda MP, Boucher D, and Schroder K
- Subjects
- Animals, Caspase 1 metabolism, Cell Death, Humans, Pyroptosis, Caspases metabolism, Inflammasomes metabolism
- Abstract
Inflammasomes are inflammatory signaling complexes that provide molecular platforms to activate the protease function of inflammatory caspases. Caspases-1, -4, -5, and -11 are inflammatory caspases activated by inflammasomes to drive lytic cell death and inflammatory mediator production, thereby activating host-protective and pathological immune responses. Here, we comprehensively review the mechanisms that govern the activity of inflammatory caspases. We discuss inflammatory caspase activation and deactivation mechanisms, alongside the physiological importance of caspase activity kinetics. We also examine mechanisms of caspase substrate selection and how inflammasome and cell identities influence caspase activity and resultant inflammatory and pyroptotic cellular programs. Understanding how inflammatory caspases are regulated may offer new strategies for treating infection and inflammasome-driven disease.
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- 2022
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25. Mathematical modelling of activation-induced heterogeneity in TNF, IL6, NOS2, and IL1β expression reveals cell state transitions underpinning macrophage responses to LPS.
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Dey S, Boucher D, Pitchford J, and Lagos D
- Abstract
Background: Despite extensive work on macrophage heterogeneity, the mechanisms driving activation induced heterogeneity (AIH) in macrophages remain poorly understood. Here, we aimed to develop mathematical models to explore theoretical cellular states underpinning the empirically observed responses of macrophages following lipopolysaccharide (LPS) challenge. Methods: We obtained empirical data following primary and secondary responses to LPS in two in vitro cellular models (bone marrow-derived macrophages or BMDMs, and RAW 264.7 cells) and single-cell protein measurements for four key inflammatory mediators: TNF, IL-6, pro-IL-1β, and NOS2, and used mathematical modelling to understand heterogeneity. Results: For these four factors, we showed that macrophage community AIH is dependent on LPS dose and that altered AIH kinetics in macrophages responding to a second LPS challenge underpin hypo-responsiveness to LPS. These empirical data can be explained by a mathematical three-state model including negative, positive, and non-responsive states (NRS), but they are also compatible with a four-state model that includes distinct reversibly NRS and non-responsive permanently states (NRPS). Our mathematical model, termed NoRM (Non-Responsive Macrophage) model identifies similarities and differences between BMDM and RAW 264.7 cell responses. In both cell types, transition rates between states in the NoRM model are distinct for each of the tested proteins and, crucially, macrophage hypo-responsiveness is underpinned by changes in transition rates to and from NRS. Conclusions: Overall, we provide a mathematical model for studying macrophage ecology and community dynamics that can be used to elucidate the role of phenotypically negative macrophage populations in AIH and, primary and secondary responses to LPS., Competing Interests: No competing interests were disclosed., (Copyright: © 2022 Dey S et al.)
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- 2022
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26. Gasdermin D Cleavage Assay Following Inflammasome Activation.
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Kamajaya LJ and Boucher D
- Subjects
- Animals, Humans, Mice, Neoplasm Proteins metabolism, Phosphate-Binding Proteins chemistry, Pyroptosis, Inflammasomes metabolism, Intracellular Signaling Peptides and Proteins metabolism
- Abstract
Gasdermin D (GSDMD) is a recently identified pore-forming protein that is crucial for the execution of pyroptosis, a highly inflammatory form of cell death. GSDMD contains an N-terminal and a C-terminal domain that are separated by a proteolysis-sensitive linker. Upon cleavage of this linker by inflammasome-activated caspases, the N-terminal domain of GSDMD oligomerizes and forms pores at the plasma membrane, allowing cell swelling and subsequently membrane rupture to mediate pyroptosis. GSDMD is a key substrate of inflammatory caspases downstream of inflammasome activation and is driving various pathologies. Here, we describe a simple method to study GSDMD cleavage following canonical inflammasome activation in murine primary macrophages and neutrophils and human cell lines using immunoblotting., (© 2022. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)
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- 2022
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27. Measuring Non-canonical Inflammasome Activation in Neutrophils.
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Monteleone M and Boucher D
- Subjects
- Animals, Caspases metabolism, Mice, Neutrophils metabolism, Pyroptosis, Extracellular Traps metabolism, Inflammasomes metabolism
- Abstract
Neutrophils are innate immune cells that play critical functions during infections through diverse mechanisms. One such mechanism, the generation of extracellular traps (NETs), enables direct bacterial killing during infections. We recently reported that the activation of the non-canonical inflammasomes in neutrophils allows for the generation of NETs and is an important host defence mechanism in vivo in response to intracellular Gram-negative bacterium. This process is dependent on inflammatory caspases and the cell death effector Gasdermin D. Here, we describe a simple approach to study the functions of the non-canonical inflammasome in murine neutrophils using microscopy and cellular fragmentation assays., (© 2022. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)
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- 2022
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28. Activation of the Non-canonical Inflammasome in Mouse and Human Cells.
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Bezbradica JS, Coll RC, and Boucher D
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- Animals, Humans, Mice, Neoplasm Proteins metabolism, Phosphate-Binding Proteins, Pyroptosis, Inflammasomes metabolism, Intracellular Signaling Peptides and Proteins metabolism
- Abstract
The non-canonical inflammasome is a signaling platform that allows for the detection of cytoplasmic lipopolysaccharides (LPS) in immune and non-immune cells. Upon detection of LPS, this inflammasome activates the signaling proteases caspase-4 and -5 (in humans) and caspase-11 (in mice). Inflammatory caspases activation leads to caspase self-processing and the cleavage of the pore-forming protein Gasdermin D (GSDMD). GSDMD N-terminal fragments oligomerize and form pores at the plasma membranes, leading to an inflammatory form of cell death called pyroptosis. Here, we describe a simple method to activate the non-canonical inflammasome in myeloid and epithelial cells and to measure its activity using cell death assay and immunoblotting., (© 2022. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)
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- 2022
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29. hSSB2 (NABP1) is required for the recruitment of RPA during the cellular response to DNA UV damage.
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Boucher D, Kariawasam R, Burgess J, Gimenez A, Ocampo TE, Ferguson B, Naqi A, Walker GJ, Bolderson E, Gamsjaeger R, O'Byrne KJ, Cubeddu L, Khanna KK, and Richard DJ
- Subjects
- Animals, Cell Line, Chromatin metabolism, DNA Damage, DNA-Binding Proteins genetics, Gene Expression Regulation radiation effects, HeLa Cells, Humans, Phosphorylation radiation effects, Up-Regulation, DNA Repair, DNA-Binding Proteins metabolism, Replication Protein A metabolism, Ultraviolet Rays adverse effects
- Abstract
Maintenance of genomic stability is critical to prevent diseases such as cancer. As such, eukaryotic cells have multiple pathways to efficiently detect, signal and repair DNA damage. One common form of exogenous DNA damage comes from ultraviolet B (UVB) radiation. UVB generates cyclobutane pyrimidine dimers (CPD) that must be rapidly detected and repaired to maintain the genetic code. The nucleotide excision repair (NER) pathway is the main repair system for this type of DNA damage. Here, we determined the role of the human Single-Stranded DNA Binding protein 2, hSSB2, in the response to UVB exposure. We demonstrate that hSSB2 levels increase in vitro and in vivo after UVB irradiation and that hSSB2 rapidly binds to chromatin. Depletion of hSSB2 results in significantly decreased Replication Protein A (RPA32) phosphorylation and impaired RPA32 localisation to the site of UV-induced DNA damage. Delayed recruitment of NER protein Xeroderma Pigmentosum group C (XPC) was also observed, leading to increased cellular sensitivity to UVB. Finally, hSSB2 was shown to have affinity for single-strand DNA containing a single CPD and for duplex DNA with a two-base mismatch mimicking a CPD moiety. Altogether our data demonstrate that hSSB2 is involved in the cellular response to UV exposure., (© 2021. The Author(s).)
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- 2021
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30. Mineral carbonation for serpentine mitigation in nickel processing: a step towards industrial carbon capture and storage.
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Khan S, Wani OB, Shoaib M, Forster J, Sodhi RN, Boucher D, and Bobicki ER
- Abstract
A proof-of-concept for the carbonation-assisted processing of ultramafic nickel ores is presented. Carbonation converts serpentine, the primary gangue or undesirable mineral, to magnesite. It prevents slime coating of fine gangue minerals on pentlandite, the main nickel-bearing mineral, during froth flotation, and improves nickel recovery and concentrate grade. Additionally, CO2 is captured and stored in the form of solid carbonates, thus removing it from the atmosphere. Microflotation experiments demonstrated improved nickel recovery (61.2 to 87.4 wt%) and concentrate grade (20.6 to 24.7 wt%) in carbonated vs. uncarbonated systems. The mechanism behind the improved nickel flotation was investigated by zeta potential measurements, optical imaging microscopy, X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry. These analyses confirmed the absence of slime coating in the carbonated system under the flotation conditions tested. Finally, a preliminary techno-economic analysis was performed to evaluate the cost metrics of incorporating carbonation into nickel mineral processing.
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- 2021
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31. Great balls of fire: activation and signalling of inflammatory caspases.
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Bateman G, Hill B, Knight R, and Boucher D
- Subjects
- Animals, Caspases metabolism, Cytokines metabolism, Enzyme Activation immunology, Humans, Inflammasomes metabolism, Inflammation metabolism, Pyroptosis immunology, Substrate Specificity, Caspases immunology, Cytokines immunology, Inflammasomes immunology, Inflammation immunology, Signal Transduction immunology
- Abstract
Innate immune responses are tightly regulated by various pathways to control infections and maintain homeostasis. One of these pathways, the inflammasome pathway, activates a family of cysteine proteases called inflammatory caspases. They orchestrate an immune response by cleaving specific cellular substrates. Canonical inflammasomes activate caspase-1, whereas non-canonical inflammasomes activate caspase-4 and -5 in humans and caspase-11 in mice. Caspases are highly specific enzymes that select their substrates through diverse mechanisms. During inflammation, caspase activity is responsible for the secretion of inflammatory cytokines and the execution of a form of lytic and inflammatory cell death called pyroptosis. This review aims to bring together our current knowledge of the biochemical processes behind inflammatory caspase activation, substrate specificity, and substrate signalling., (© 2021 The Author(s).)
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- 2021
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32. Discovery of Potent, Selective Triazolothiadiazole-Containing c-Met Inhibitors.
- Author
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Tang Q, Aronov AM, Deininger DD, Giroux S, Lauffer DJ, Li P, Liang J, McGinty K, Ronkin S, Swett R, Waal N, Boucher D, Ford PJ, and Moody CS
- Abstract
Herein, we report a novel series of highly potent and selective triazolothiadiazole c-Met inhibitors. Starting with molecule 5 , we have applied structure-based drug design principles to identify the triazolothiadiazole ring system. We successfully replaced the metabolically unstable phenolic moiety with a quinoline group. Further optimization around the 5,6 bicyclic moiety led to the identification of 21 . Compound 21 suffered from PDE3 selectivity issues and subsequent, structurally informed design led to the discovery of compound 23 . Compound 23 has exquisite kinase selectivity, excellent potency, favorable ADME profile, and showed dose-dependent antitumor efficacy in a SNU-5 gastric cancer xenograft model., Competing Interests: The authors declare no competing financial interest., (© 2021 American Chemical Society.)
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- 2021
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33. Barrier-to-autointegration-factor (Banf1) modulates DNA double-strand break repair pathway choice via regulation of DNA-dependent kinase (DNA-PK) activity.
- Author
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Burgess JT, Cheong CM, Suraweera A, Sobanski T, Beard S, Dave K, Rose M, Boucher D, Croft LV, Adams MN, O'Byrne K, Richard DJ, and Bolderson E
- Subjects
- Cell Line, HEK293 Cells, Homologous Recombination, Humans, DNA Breaks, Double-Stranded, DNA Repair, DNA-Activated Protein Kinase metabolism, DNA-Binding Proteins metabolism
- Abstract
DNA repair pathways are essential to maintain the integrity of the genome and prevent cell death and tumourigenesis. Here, we show that the Barrier-to-Autointegration Factor (Banf1) protein has a role in the repair of DNA double-strand breaks. Banf1 is characterized as a nuclear envelope protein and mutations in Banf1 are associated with the severe premature aging syndrome, Néstor-Guillermo Progeria Syndrome. We have previously shown that Banf1 directly regulates the activity of PARP1 in the repair of oxidative DNA lesions. Here, we show that Banf1 also has a role in modulating DNA double-strand break repair through regulation of the DNA-dependent Protein Kinase catalytic subunit, DNA-PKcs. Specifically, we demonstrate that Banf1 relocalizes from the nuclear envelope to sites of DNA double-strand breaks. We also show that Banf1 can bind to and directly inhibit the activity of DNA-PKcs. Supporting this, cellular depletion of Banf1 leads to an increase in non-homologous end-joining and a decrease in homologous recombination, which our data suggest is likely due to unrestrained DNA-PKcs activity. Overall, this study identifies how Banf1 regulates double-strand break repair pathway choice by modulating DNA-PKcs activity to control genome stability within the cell., (© The Author(s) 2021. Published by Oxford University Press on behalf of Nucleic Acids Research.)
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- 2021
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34. Reply to López-Cortés et al.
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Leroy AG, Corvec S, Danneels P, Dubée V, Kempf M, Boucher D, Issa N, Peuchant O, Camou F, Boutoille D, and Lecomte R
- Subjects
- Chronic Disease, Humans, Recurrence, Endocarditis
- Published
- 2021
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35. A mixed methods analysis of access barriers to dermatology care in a rural state.
- Author
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Cyr ME, Boucher D, Korona SA, Guthrie BJ, and Benneyan JC
- Subjects
- Health Services Accessibility, Humans, Primary Health Care, Retrospective Studies, Rural Population, Surveys and Questionnaires, Dermatology, Rural Health Services
- Abstract
Aims: To identify significant patient and system access barriers and facilitators to dermatology care in one rural health system with limited dermatology appointment availability., Design: Mixed methods study using data from electronic medical records, patient surveys, stakeholder semi-structured interviews, and service area dermatologist demographics. Retrospective data were collected between 1 January 2017-1 March 2018, and interviews and surveys were conducted between June 1-August 31, 2018. Participants were recruited from two primary care practices in one rural Maine regional health system., Methods: Findings from thematic analyses, descriptive statistics, and statistical modelling were integrated using Chi-square tests for homogeneity to develop a unified understanding. Statistical modelling using odd-ratio logistic and linear regression were performed for each outcome variable of interest., Results: Urgent referrals by primary care increased the likelihood of dermatology care overall (OR: 6.771; p = .007) and at nearby sites with limited availability (OR: 4.024; p = .024), but not at geographically further sites with higher capacities (p = .844). Referral under-diagnosis occurred in 20.8% of those biopsied. Older (p = .041) or non-working (p = .021) patients were more likely to remain unevaluated than seek more available but geographically further care., Conclusions: In rural areas with scarce appointment availability, primary care provider diagnostic accuracy may be an important barrier of dermatology care receipt and health outcomes, especially among at-risk populations., Impact: Although melanoma mortality rates are decreasing throughout the US, little is known about why rates in Maine continue to rise. This study applied a comprehensive approach to identify several patient and system access barriers to dermatology care in one underserved rural regional health system. While specific to this population and large service area, these findings will inform improvement efforts here and support broader future research efforts aimed at understanding and improving health outcomes in this rural state., (© 2020 John Wiley & Sons Ltd.)
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- 2021
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36. Early Career Development and Graduate Medical Education Leadership Pathways.
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Boucher D, Martin S, Xi AS, and Rialon KL
- Subjects
- Career Choice, Education, Medical, Graduate, Humans, Internship and Residency, Leadership
- Published
- 2020
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37. Inflammatory and oxidative status in European captive black rhinoceroses: A link with Iron Overload Disorder?
- Author
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Pouillevet H, Soetart N, Boucher D, Wedlarski R, and Jaillardon L
- Subjects
- Animals, Animals, Zoo metabolism, Disease Susceptibility metabolism, Female, Inflammation metabolism, Iron metabolism, Liver metabolism, Male, Oxidative Stress physiology, Prospective Studies, Iron Overload immunology, Iron Overload metabolism, Perissodactyla metabolism
- Abstract
Iron Overload Disorder (IOD) is a syndrome developed by captive browsing rhinoceroses like black rhinoceroses (Diceros bicornis), in which hemosiderosis develops in vital organs while free iron accumulates in the body, potentially predisposing to various secondary diseases. Captive grazing species like white rhinoceroses (Ceratotherium simum) do not seem to be affected. The authors hypothesized that inflammation and oxidative stress may be implicated in the pathogenesis of IOD in captive black rhinoceroses, making this syndrome a potential common denominator to various diseases described in captivity in this species. In this prospective study, 15 black (BR) and 29 white rhinoceroses (WR) originating from 22 European zoos were blood-sampled and compared for their iron status (serum iron), liver/muscle biochemical parameters (AST, GGT, cholesterol), inflammatory status (total proteins, protein electrophoresis) and oxidative stress markers (SOD, GPX, dROMs). Results showed higher serum iron and liver enzyme levels in black rhinoceroses (P < 0.01), as well as higher dROMs (P < 0.01) and a trend for higher GPX (P = 0.06) levels. The albumin/globulin ratio was lower in black rhinoceroses (P < 0.05) due to higher α2-globulin levels (P < 0.001). The present study suggests a higher inflammatory and oxidative profile in captive BR than in WR, possibly in relation to iron status. This could be either a consequence or a cause of iron accumulation. Further investigations are needed to assess the prognostic value of the inflammatory and oxidative markers in captive black rhinoceroses, particularly for evaluating the impact of reduced-iron and antioxidant-supplemented diets., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2020
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38. Correlates of sugar-sweetened beverages consumption among adolescents.
- Author
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Beaulieu D, Vézina-Im LA, Turcotte S, Guillaumie L, Boucher D, Douville F, and Simard D
- Subjects
- Adolescent, Canada, Female, Humans, Male, Quebec, Schools, Choice Behavior, Consumer Behavior, Sugar-Sweetened Beverages
- Abstract
Objective: To identify correlates and underlying beliefs regarding the adolescents' intention to abstain from consuming sugar-sweetened beverages (SSB) and the consumption of ≤1 daily portion of SSB., Design: Correlational study., Setting: Region of Chaudière-Appalaches in the province of Quebec, Canada., Participants: 311 adolescents aged 13-18 years completed a self-administrated online questionnaire based on the Reasoned Action Approach. Frequency and quantity of different types of SSB within the past month were measured., Results: Total mean SSB intake was 882·6 ml/d (654·0 kJ/d ). Only 11·3 % abstained from SSB within the last month. Intention to abstain from SSB was explained by identification as SSB abstainers (β = 0·47), perceived norm (β = 0·32), attitude (β = 0·30), age 13-14 years (β = -0·27) and perception of the school environment (β = 0·14), which explained 66 % of the variance. Consumption of ≤1 daily portion of SSB was explained by the intention to abstain (OR = 1·55; 95 % CI 1·14, 2·11), perceived behavioural control to abstain (OR = 1·80; 95 % CI 1·29, 2·52), sex (girls v. boys: OR = 2·34; 95 % CI 1·37, 3·98) and socio-economic status (advantaged v. disadvantaged school: OR = 2·08; 95 % CI 1·21, 3·56). Underlying beliefs (i.e. more energy, decreased risk of addiction and friends' approval) associated with intention as well as perceived barriers (e.g. access to SSB, after an activity that makes you thirsty), and facilitating factors (e.g. access to water) linked to SSB consumption were identified., Conclusions: The results can inform public health interventions to decrease SSB consumption and their associated health problems among adolescents.
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- 2020
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39. The Therapeutic Potential of DNA Damage Repair Pathways and Genomic Stability in Lung Cancer.
- Author
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Burgess JT, Rose M, Boucher D, Plowman J, Molloy C, Fisher M, O'Leary C, Richard DJ, O'Byrne KJ, and Bolderson E
- Abstract
Despite advances in our understanding of the molecular biology of the disease and improved therapeutics, lung cancer remains the most common cause of cancer-related deaths worldwide. Therefore, an unmet need remains for improved treatments, especially in advanced stage disease. Genomic instability is a universal hallmark of all cancers. Many of the most commonly prescribed chemotherapeutics, including platinum-based compounds such as cisplatin, target the characteristic genomic instability of tumors by directly damaging the DNA. Chemotherapies are designed to selectively target rapidly dividing cells, where they cause critical DNA damage and subsequent cell death (1, 2). Despite the initial efficacy of these drugs, the development of chemotherapy resistant tumors remains the primary concern for treatment of all lung cancer patients. The correct functioning of the DNA damage repair machinery is essential to ensure the maintenance of normal cycling cells. Dysregulation of these pathways promotes the accumulation of mutations which increase the potential of malignancy. Following the development of the initial malignancy, the continued disruption of the DNA repair machinery may result in the further progression of metastatic disease. Lung cancer is recognized as one of the most genomically unstable cancers (3). In this review, we present an overview of the DNA damage repair pathways and their contributions to lung cancer disease occurrence and progression. We conclude with an overview of current targeted lung cancer treatments and their evolution toward combination therapies, including chemotherapy with immunotherapies and antibody-drug conjugates and the mechanisms by which they target DNA damage repair pathways., (Copyright © 2020 Burgess, Rose, Boucher, Plowman, Molloy, Fisher, O'Leary, Richard, O'Byrne and Bolderson.)
- Published
- 2020
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40. Human GBP1 binds LPS to initiate assembly of a caspase-4 activating platform on cytosolic bacteria.
- Author
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Santos JC, Boucher D, Schneider LK, Demarco B, Dilucca M, Shkarina K, Heilig R, Chen KW, Lim RYH, and Broz P
- Subjects
- Cell Line, Enzyme Activation, Epithelial Cells metabolism, HeLa Cells, Humans, Inflammasomes metabolism, Intracellular Signaling Peptides and Proteins metabolism, Phosphate-Binding Proteins metabolism, Protein Binding, Pyroptosis, Static Electricity, Caspases, Initiator metabolism, Cytosol microbiology, GTP-Binding Proteins metabolism, Lipopolysaccharides metabolism, Salmonella metabolism
- Abstract
The human non-canonical inflammasome controls caspase-4 activation and gasdermin-D-dependent pyroptosis in response to cytosolic bacterial lipopolysaccharide (LPS). Since LPS binds and oligomerizes caspase-4, the pathway is thought to proceed without dedicated LPS sensors or an activation platform. Here we report that interferon-induced guanylate-binding proteins (GBPs) are required for non-canonical inflammasome activation by cytosolic Salmonella or upon cytosolic delivery of LPS. GBP1 associates with the surface of cytosolic Salmonella seconds after bacterial escape from their vacuole, initiating the recruitment of GBP2-4 to assemble a GBP coat. The GBP coat then promotes the recruitment of caspase-4 to the bacterial surface and caspase activation, in absence of bacteriolysis. Mechanistically, GBP1 binds LPS with high affinity through electrostatic interactions. Our findings indicate that in human epithelial cells GBP1 acts as a cytosolic LPS sensor and assembles a platform for caspase-4 recruitment and activation at LPS-containing membranes as the first step of non-canonical inflammasome signaling.
- Published
- 2020
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41. Caspase-1 cleaves Bid to release mitochondrial SMAC and drive secondary necrosis in the absence of GSDMD.
- Author
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Heilig R, Dilucca M, Boucher D, Chen KW, Hancz D, Demarco B, Shkarina K, and Broz P
- Subjects
- Animals, Apoptosis genetics, BH3 Interacting Domain Death Agonist Protein genetics, Caspase 1 genetics, Cells, Cultured, Gene Editing, Gene Knockout Techniques, Inflammasomes metabolism, Intracellular Signaling Peptides and Proteins genetics, Macrophages metabolism, Macrophages pathology, Mice, Mice, Inbred C57BL, Mice, Knockout, Mitochondrial Membranes metabolism, Necrosis genetics, Necrosis metabolism, Phosphate-Binding Proteins genetics, Pyroptosis genetics, Transfection, Apoptosis Regulatory Proteins metabolism, BH3 Interacting Domain Death Agonist Protein deficiency, Caspase 1 deficiency, Intracellular Signaling Peptides and Proteins deficiency, Mitochondria metabolism, Mitochondrial Proteins metabolism, Phosphate-Binding Proteins deficiency, Signal Transduction genetics
- Abstract
Caspase-1 drives a lytic inflammatory cell death named pyroptosis by cleaving the pore-forming cell death executor gasdermin-D (GSDMD). Gsdmd deficiency, however, only delays cell lysis, indicating that caspase-1 controls alternative cell death pathways. Here, we show that in the absence of GSDMD, caspase-1 activates apoptotic initiator and executioner caspases and triggers a rapid progression into secondary necrosis. GSDMD-independent cell death required direct caspase-1-driven truncation of Bid and generation of caspase-3 p19/p12 by either caspase-8 or caspase-9. tBid-induced mitochondrial outer membrane permeabilization was also required to drive SMAC release and relieve inhibitor of apoptosis protein inhibition of caspase-3, thereby allowing caspase-3 auto-processing to the fully active p17/p12 form. Our data reveal that cell lysis in inflammasome-activated Gsdmd -deficient cells is caused by a synergistic effect of rapid caspase-1-driven activation of initiator caspases-8/-9 and Bid cleavage, resulting in an unusually fast activation of caspase-3 and immediate transition into secondary necrosis. This pathway might be advantageous for the host in counteracting pathogen-induced inhibition of GSDMD but also has implications for the use of GSDMD inhibitors in immune therapies for caspase-1-dependent inflammatory disease., (© 2020 Heilig et al.)
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- 2020
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42. The structural details of the interaction of single-stranded DNA binding protein hSSB2 (NABP1/OBFC2A) with UV-damaged DNA.
- Author
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Lawson T, El-Kamand S, Boucher D, Duong DC, Kariawasam R, Bonvin AMJJ, Richard DJ, Gamsjaeger R, and Cubeddu L
- Subjects
- Binding Sites genetics, DNA Repair, DNA, Single-Stranded genetics, DNA, Single-Stranded metabolism, DNA-Binding Proteins genetics, DNA-Binding Proteins metabolism, HeLa Cells, Humans, Interferometry methods, Magnetic Resonance Spectroscopy methods, Mitochondrial Proteins chemistry, Mitochondrial Proteins genetics, Mitochondrial Proteins metabolism, Models, Molecular, Oligonucleotides genetics, Oligonucleotides metabolism, Protein Binding, Protein Domains, DNA Damage, DNA, Single-Stranded chemistry, DNA-Binding Proteins chemistry, Ultraviolet Rays
- Abstract
Single-stranded DNA-binding proteins (SSBs) are required for all known DNA metabolic events such as DNA replication, recombination and repair. While a wealth of structural and functional data is available on the essential human SSB, hSSB1 (NABP2/OBFC2B), the close homolog hSSB2 (NABP1/OBFC2A) remains relatively uncharacterized. Both SSBs possess a well-structured OB (oligonucleotide/oligosaccharide-binding) domain that is able to recognize single-stranded DNA (ssDNA) followed by a flexible carboxyl-tail implicated in the interaction with other proteins. Despite the high sequence similarity of the OB domain, several recent studies have revealed distinct functional differences between hSSB1 and hSSB2. In this study, we show that hSSB2 is able to recognize cyclobutane pyrimidine dimers (CPD) that form in cellular DNA as a consequence of UV damage. Using a combination of biolayer interferometry and NMR, we determine the molecular details of the binding of the OB domain of hSSB2 to CPD-containing ssDNA, confirming the role of four key aromatic residues in hSSB2 (W59, Y78, W82, and Y89) that are also conserved in hSSB1. Our structural data thus demonstrate that ssDNA recognition by the OB fold of hSSB2 is highly similar to hSSB1, indicating that one SSB may be able to replace the other in any initial ssDNA binding event. However, any subsequent recruitment of other repair proteins most likely depends on the divergent carboxyl-tail and as such is likely to be different between hSSB1 and hSSB2., (© 2019 Wiley Periodicals, Inc.)
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- 2020
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43. Redox Regulation in the Base Excision Repair Pathway: Old and New Players as Cancer Therapeutic Targets.
- Author
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Rajapakse A, Suraweera A, Boucher D, Naqi A, O'Byrne K, Richard DJ, and Croft LV
- Subjects
- Animals, DNA, DNA Damage, Humans, Oxidation-Reduction, DNA Repair, Neoplasms
- Abstract
Background: Reactive Oxygen Species (ROS) are by-products of normal cellular metabolic processes, such as mitochondrial oxidative phosphorylation. While low levels of ROS are important signalling molecules, high levels of ROS can damage proteins, lipids and DNA. Indeed, oxidative DNA damage is the most frequent type of damage in the mammalian genome and is linked to human pathologies such as cancer and neurodegenerative disorders. Although oxidative DNA damage is cleared predominantly through the Base Excision Repair (BER) pathway, recent evidence suggests that additional pathways such as Nucleotide Excision Repair (NER) and Mismatch Repair (MMR) can also participate in clearance of these lesions. One of the most common forms of oxidative DNA damage is the base damage 8-oxoguanine (8-oxoG), which if left unrepaired may result in G:C to A:T transversions during replication, a common mutagenic feature that can lead to cellular transformation., Objective: Repair of oxidative DNA damage, including 8-oxoG base damage, involves the functional interplay between a number of proteins in a series of enzymatic reactions. This review describes the role and the redox regulation of key proteins involved in the initial stages of BER of 8-oxoG damage, namely Apurinic/Apyrimidinic Endonuclease 1 (APE1), human 8-oxoguanine DNA glycosylase-1 (hOGG1) and human single-stranded DNA binding protein 1 (hSSB1). Moreover, the therapeutic potential and modalities of targeting these key proteins in cancer are discussed., Conclusion: It is becoming increasingly apparent that some DNA repair proteins function in multiple repair pathways. Inhibiting these factors would provide attractive strategies for the development of more effective cancer therapies., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)
- Published
- 2020
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44. Barrier-to-autointegration factor 1 (Banf1) regulates poly [ADP-ribose] polymerase 1 (PARP1) activity following oxidative DNA damage.
- Author
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Bolderson E, Burgess JT, Li J, Gandhi NS, Boucher D, Croft LV, Beard S, Plowman JJ, Suraweera A, Adams MN, Naqi A, Zhang SD, Sinclair DA, O'Byrne KJ, and Richard DJ
- Subjects
- Cell Line, Tumor, DNA-Binding Proteins genetics, HEK293 Cells, Humans, Mutation genetics, Poly (ADP-Ribose) Polymerase-1 chemistry, Poly Adenosine Diphosphate Ribose metabolism, Progeria metabolism, Protein Binding, Protein Domains, DNA Damage, DNA-Binding Proteins metabolism, Oxidative Stress, Poly (ADP-Ribose) Polymerase-1 metabolism
- Abstract
The DNA repair capacity of human cells declines with age, in a process that is not clearly understood. Mutation of the nuclear envelope protein barrier-to-autointegration factor 1 (Banf1) has previously been shown to cause a human progeroid disorder, Néstor-Guillermo progeria syndrome (NGPS). The underlying links between Banf1, DNA repair and the ageing process are unknown. Here, we report that Banf1 controls the DNA damage response to oxidative stress via regulation of poly [ADP-ribose] polymerase 1 (PARP1). Specifically, oxidative lesions promote direct binding of Banf1 to PARP1, a critical NAD
+ -dependent DNA repair protein, leading to inhibition of PARP1 auto-ADP-ribosylation and defective repair of oxidative lesions, in cells with increased Banf1. Consistent with this, cells from patients with NGPS have defective PARP1 activity and impaired repair of oxidative lesions. These data support a model whereby Banf1 is crucial to reset oxidative-stress-induced PARP1 activity. Together, these data offer insight into Banf1-regulated, PARP1-directed repair of oxidative lesions.- Published
- 2019
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45. Isolation of Neutrophil Nuclei for Use in NETosis Assays.
- Author
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Boucher D
- Abstract
Neutrophils are critical immune cells that protect our body against invading pathogens. They generate antibacterial DNA structures called neutrophil extracellular traps (NET). Recently we identified a new mechanism that enables NET formation. We observed that following recognition of lipopolysaccharides, inflammatory caspases cleave Gasdermin D and enable NET generation ( Chen et al. , 2018 ). This protocol describes how we purify neutrophil nuclei to visualize NET formation by live microscopy. After neutrophil purification from murine bone marrow, neutrophils are lysed in a hypotonic buffer using a nitrogen cavitation device to prevent lysis of neutrophil granules and subsequent contamination by granules proteases. Lysed neutrophils are then centrifuged, and nuclei are counted. The protocol described here is straightforward and enables the study of early changes happening in the nuclei of neutrophils undergoing NETosis with limited contamination by granule proteases., Competing Interests: Competing interestsThe author has no competing interests to declare., (Copyright © 2019 The Authors; exclusive licensee Bio-protocol LLC.)
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- 2019
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46. Variation in hemolysin A expression between uropathogenic Escherichia coli isolates determines NLRP3-dependent vs. -independent macrophage cell death and host colonization.
- Author
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Murthy AMV, Sullivan MJ, Nhu NTK, Lo AW, Phan MD, Peters KM, Boucher D, Schroder K, Beatson SA, Ulett GC, Schembri MA, and Sweet MJ
- Subjects
- Animals, Escherichia coli Infections microbiology, Humans, Mice, Urinary Tract Infections microbiology, Cell Death, Escherichia coli Proteins metabolism, Hemolysin Proteins metabolism, Host-Pathogen Interactions, Macrophages cytology, NLR Family, Pyrin Domain-Containing 3 Protein metabolism, Uropathogenic Escherichia coli metabolism
- Abstract
Uropathogenic Escherichia coli (UPEC) is the major cause of urinary tract infections (UTIs). The multidrug-resistant E. coli sequence type 131 (ST131) clone is a serious threat to human health, yet its effects on immune responses are not well understood. Here we screened a panel of ST131 isolates, finding that only strains expressing the toxin hemolysin A (HlyA) killed primary human macrophages and triggered maturation of the inflammasome-dependent cytokine IL-1β. Using a representative strain, the requirement for the hlyA gene in these responses was confirmed. We also observed considerable heterogeneity in levels of cell death initiated by different HlyA
+ve ST131 isolates, and this correlated with secreted HlyA levels. Investigation into the biological significance of this variation revealed that an ST131 strain producing low levels of HlyA initiated cell death that was partly dependent on the nod-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, with this response being associated with a host-protective role in a mouse UTI model. When the same ST131 strain was engineered to overexpress high HlyA levels, macrophage cell death occurred even when NLRP3 function was abrogated, and bladder colonization was significantly increased. Thus, variation in HlyA expression in UPEC affects mechanisms by which macrophages die, as well as host susceptibility vs. resistance to colonization.-Murthy, A. M. V., Sullivan, M. J., Nhu, N. T. K., Lo, A. W., Phan, M.-D., Peters, K. M., Boucher, D., Schroder, K., Beatson, S. A., Ulett, G. C., Schembri, M. A., Sweet, M. J. Variation in hemolysin A expression between uropathogenic Escherichia coli isolates determines NLRP3-dependent vs. -independent macrophage cell death and host colonization.- Published
- 2019
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47. MCC950 directly targets the NLRP3 ATP-hydrolysis motif for inflammasome inhibition.
- Author
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Coll RC, Hill JR, Day CJ, Zamoshnikova A, Boucher D, Massey NL, Chitty JL, Fraser JA, Jennings MP, Robertson AAB, and Schroder K
- Subjects
- Adenosine Triphosphate metabolism, Binding Sites drug effects, Furans, Heterocyclic Compounds, 4 or More Rings chemistry, Humans, Hydrolysis drug effects, Indenes, Inflammasomes biosynthesis, NLR Family, Pyrin Domain-Containing 3 Protein metabolism, Sulfonamides, Sulfones chemistry, Adenosine Triphosphate antagonists & inhibitors, Heterocyclic Compounds, 4 or More Rings pharmacology, Inflammasomes antagonists & inhibitors, NLR Family, Pyrin Domain-Containing 3 Protein antagonists & inhibitors, Sulfones pharmacology
- Abstract
Inhibition of the NLRP3 inflammasome is a promising strategy for the development of new treatments for inflammatory diseases. MCC950 is a potent and specific small-molecule inhibitor of the NLRP3 pathway, but its molecular target is not defined. Here, we show that MCC950 directly interacts with the Walker B motif within the NLRP3 NACHT domain, thereby blocking ATP hydrolysis and inhibiting NLRP3 activation and inflammasome formation.
- Published
- 2019
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48. Divide to conquer: NLRP3 is activated on dispersed trans-Golgi network.
- Author
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Chen KW, Boucher D, and Broz P
- Subjects
- NLR Family, Pyrin Domain-Containing 3 Protein, Phosphatidylinositol Phosphates, Inflammasomes, trans-Golgi Network
- Published
- 2019
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49. [The effect of a polarity intervention on the insomnia and anxiety in middle-aged Quebec women].
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Lambert J, Ouellet N, and Boucher D
- Subjects
- Adult, Female, Humans, Middle Aged, Quebec, Treatment Outcome, Anxiety therapy, Sleep Initiation and Maintenance Disorders therapy
- Abstract
Many symptoms of menopause may contribute to poor sleep and insomnia. These symptoms may also be associated with anxiety and affect the quality of women’s lives. The purpose of this study was to assess the effectiveness of a polarity therapy on insomnia and anxiety for women aged 40 to 60 years old. Forty-seven women participated in this experimental study. The participants were randomly assigned to the experiment group (n = 25)—receiving 4 sessions on polarity—or to the control group (n = 22)—receiving information on healthy sleep habits. Data were collected during the pre-test and the post-test using the Morin Insomnia Severity Index and the Spielberger State-Trait Anxiety Inventory (FormY). A significant difference was found between the groups and the measurement time with respect to insomnia scores (F = 28,66 ; p < 0,0001) and anxiety scores (F = 14.14; p < 0.0001). Women who received the polarity intervention showed a significant decrease in the severity of their insomnia and of their state of anxiety compared to those in the control group during post intervention. The polarity intervention was effective in reducing the women’s symptoms of insomnia and anxiety in the middle-aged women.
- Published
- 2019
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50. The Salmonella pathogenicity island-2 subverts human NLRP3 and NLRC4 inflammasome responses.
- Author
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Bierschenk D, Monteleone M, Moghaddas F, Baker PJ, Masters SL, Boucher D, and Schroder K
- Subjects
- Animals, Cell Death, Humans, Interleukin-1beta metabolism, Macrophages metabolism, Macrophages microbiology, Mice, Inbred C57BL, Myeloid Cells metabolism, Pyroptosis, CARD Signaling Adaptor Proteins metabolism, Calcium-Binding Proteins metabolism, Genomic Islands, Inflammasomes metabolism, NLR Family, Pyrin Domain-Containing 3 Protein metabolism, Salmonella typhimurium genetics
- Abstract
Inflammasomes are signaling hubs that activate inflammatory caspases to drive cytokine maturation and cell lysis. Inflammasome activation by Salmonella Typhimurium infection or Salmonella-derived molecules is extensively studied in murine myeloid cells. Salmonella-induced inflammasome signaling in human innate immune cells, is however, poorly characterized. Here, we show that Salmonella mutation to inactivate the Salmonella pathogenicity island-2 type III secretion system (SPI2 T3SS) potentiates S. Typhimurium-induced inflammasome responses from primary human macrophages, resulting in strong IL-1β production and macrophage death. Inactivation of the SPI1 T3SS diminished human macrophage responses to WT and ΔSPI2 Salmonella. Salmonella ΔSPI2 elicited a mixed inflammasome response from human myeloid cells, in which NLR family CARD-domain containing protein 4 (NLRC4) and NLR family PYRIN-domain containing protein 3 (NLRP3) perform somewhat redundant functions in generating IL-1β and inducing pyroptosis. Our data suggest that Salmonella employs the SPI2 T3SS to subvert SPI1-induced NLRP3 and NLRC4 inflammasome responses in human primary macrophages, in a species-specific immune evasion mechanism., (©2018 Society for Leukocyte Biology.)
- Published
- 2019
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