Risk of peanut- and tree-nut-induced anaphylaxis during Halloween, Easter and other cultural holidays in Canadian children.

BACKGROUND: It is not established whether the risk of anaphylaxis induced by peanuts or tree nuts in children increases at specific times of the year. We aimed to evaluate the risk of peanut-and tree-nut-induced anaphylaxis during certain cultural holidays in Canadian children. METHODS: We collected data on confirmed pediatric cases of anaphylaxis presenting to emergency departments in 4 Canadian provinces as part of the Cross-Canada Anaphylaxis Registry. We assessed the mean number of cases per day and incidence rate ratio (IRR) of anaphylaxis induced by unknown nuts, peanuts and tree nuts presenting during each of 6 holidays (Halloween, Christmas, Easter, Diwali, Chinese New Year and Eid al-Adha) versus the rest of the year. We estimated IRRs and 95% confidence intervals (CIs) using Poisson regression. RESULTS: Data were collected for 1390 pediatric cases of anaphylaxis between 2011 and 2020. Their median age was 5.4 years, and 864 (62.2%) of the children were boys. During Halloween and Easter, there were higher rates of anaphylaxis to unknown nuts (IRR 1.66, 95% CI 1.13-2.43 and IRR 1.71, 95% CI 1.21-2.42, respectively) and peanuts (IRR 1.86, 95% CI 1.12-3.11 and IRR 1.57, 95% CI 0.94-2.63, respectively) compared to the rest of the year. No increased risk of peanut- or tree-nut-induced anaphylaxis was observed during Christmas, Diwali, Chinese New Year or Eid al-Adha. Anaphylaxis induced by unknown nuts, peanuts and tree nuts was more likely in children aged 6 years or older than in younger children. INTERPRETATION: We found an increased risk of anaphylaxis induced by unknown nuts and peanuts during Halloween and Easter among Canadian children. Educational tools are needed to increase awareness and vigilance in order to decrease the risk of anaphylaxis induced by peanuts and tree nuts in children during these holidays

Peanut Can Be Used as a Reference Allergen for Hazard Characterization in Food Allergen Risk Management: A Rapid Evidence Assessment and Meta-Analysis

Regional and national legislation mandates the disclosure of “priority” allergens when present as an ingredient in foods, but this does not extend to the unintended presence of allergens due to shared production facilities. This has resulted in a proliferation of precautionary allergen (“may contain”) labels (PAL) that are frequently ignored by food-allergic consumers. Attempts have been made to improve allergen risk management to better inform the use of PAL, but a lack of consensus has led to variety of regulatory approaches and nonuniformity in the use of PAL by food businesses. One potential solution would be to establish internationally agreed “reference doses,” below which no PAL would be needed. However, if reference doses are to be used to inform the need for PAL, then it is essential to characterize the hazard associated with these low-level exposures. For peanut, there are now published data relating to over 3000 double-blind, placebo-controlled challenges in allergic individuals, but a similar level of evidence is lacking for other priority allergens. We present the results of a rapid evidence assessment and meta-analysis for the risk of anaphylaxis to a low-level allergen exposure for priority allergens. On the basis of this analysis, we propose that peanut can and should be considered an exemplar allergen for the hazard characterization at a low-level allergen exposure. Resumen: La legislación regional y nacional exige la divulgación de alérgenos "prioritarios" cuando están presentes como ingrediente en los alimentos, pero esto no se extiende a la presencia involuntaria de alérgenos debido a instalaciones de producción compartidas. Esto ha dado lugar a una proliferación de etiquetas de precaución para alérgenos ("pueden contener") (PAL) que los consumidores alérgicos a los alimentos suelen ignorar. Se han hecho intentos para mejorar la gestión del riesgo de alérgenos para informar mejor el uso de PAL, pero la falta de consenso ha llevado a una variedad de enfoques regulatorios y a la falta de uniformidad en el uso de PAL por parte de las empresas alimentarias. Una posible solución sería establecer “dosis de referencia” acordadas internacionalmente, por debajo de las cuales no se necesitaría PAL. Sin embargo, si se van a utilizar dosis de referencia para informar la necesidad de PAL, entonces es esencial caracterizar el peligro asociado con estas exposiciones de bajo nivel. Para el maní, ahora hay datos publicados relacionados con más de 3000 desafíos doble ciego controlados por placebo en individuos alérgicos, pero falta un nivel similar de evidencia para otros alérgenos prioritarios. Presentamos los resultados de una evaluación rápida de la evidencia y un metanálisis del riesgo deanafilaxia a una exposición a alérgenos de bajo nivel para alérgenos prioritarios. Sobre la base de este análisis, proponemos que el cacahuete puede y debe considerarse un alérgeno ejemplar para la caracterización del peligro en una exposición a un alérgeno de bajo nivel.Instituto de Investigación de Tecnología de AlimentosFil: Turner, Paul J. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Patel, Nandinee. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Ballmer-Weber, Barbara K. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Ballmer-Weber, Barbara K. Clínica de Dermatología y Alergología. Kantonsspital; Suiza.Fil: Baumert, Joe L. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Blom, W. Marty. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Brooke-Taylor, Simon. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Brough, Helen. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Brough, Helen. King's College London. Departamento de Alergia Pediátrica; Reino Unido.Fil: Campbell, Dianne E. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Campbell, Dianne E. Tecnologías DBV. Montrouge; Francia.Fil: Chen, Hongbing. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Chinthrajah, R. Sharon. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Crevel, René W.R. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Dubois, Anthony E.J. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Ebisawa, Motohiro. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Elizur, Arnon. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Elizur, Arnon. Universidad de Tel Aviv. Facultad de Medicina Sackler. Departamento de Pediatría; Israel.Fil: Gerdts, Jennifer D. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Gowland, M. Hazel. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Houben, Geert F. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Hourihane, Jonathan O.B. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Knulst, André C. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: La Vieille, Sébastien. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: López, María Cristina. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Mills, E.N. Clare. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Polenta, Gustavo Alberto. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación Tecnología de Alimentos; Argentina.Fil: Polenta, Gustavo Alberto. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Purington, Natasha. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Said, María. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Sampson, Hugh A. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Sampson, Hugh A. Escuela de Medicina Icahn. División de Alergia e Inmunología Pediátricasen. Nueva York. Estados Unidos de América.Fil: Schnadt, Sabine. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Södergren, Eva. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Södergren, Eva. ThermoFisher Scientific; Suecia.Fil: Taylor, Stephen L. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Remington, Benjamin C. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Remington, Benjamin C. Grupo BV. Consultoría Remington; Holanda

Analysis of the CD1 Antigen Presenting System in Humanized SCID Mice

CD1 molecules are glycoproteins that present lipids and glycolipids for recognition by T cells. CD1-dependent immune activation has been implicated in a wide range of immune responses, however, our understanding of the role of this pathway in human disease remains limited because of species differences between humans and other mammals: whereas humans express five different CD1 gene products (CD1a, CD1b, CD1c, CD1d, and CD1e), muroid rodents express only one CD1 isoform (CD1d). Here we report that immune deficient mice engrafted with human fetal thymus, liver, and CD34+ hematopoietic stem cells develop a functional human CD1 compartment. CD1a, b, c, and d isoforms were highly expressed by human thymocytes, and CD1a+ cells with a dendritic morphology were present in the thymic medulla. CD1+ cells were also detected in spleen, liver, and lungs. APCs from spleen and liver were capable of presenting bacterial glycolipids to human CD1-restricted T cells. ELISpot analyses of splenocytes demonstrated the presence of CD1-reactive IFN-γ producing cells. CD1d tetramer staining directly identified human iNKT cells in spleen and liver samples from engrafted mice, and injection of the glycolipid antigen α-GalCer resulted in rapid elevation of human IFN-γ and IL-4 levels in the blood indicating that the human iNKT cells are biologically active in vivo. Together, these results demonstrate that the human CD1 system is present and functionally competent in this humanized mouse model. Thus, this system provides a new opportunity to study the role of CD1-related immune activation in infections to human-specific pathogens

A communal catalogue reveals Earth's multiscale microbial diversity

Our growing awareness of the microbial world's importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth's microbial diversity.Peer reviewe

A communal catalogue reveals Earth’s multiscale microbial diversity

Our growing awareness of the microbial world’s importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth’s microbial diversity

Effects of eight neuropsychiatric copy number variants on human brain structure

Many copy number variants (CNVs) confer risk for the same range of neurodevelopmental symptoms and psychiatric conditions including autism and schizophrenia. Yet, to date neuroimaging studies have typically been carried out one mutation at a time, showing that CNVs have large effects on brain anatomy. Here, we aimed to characterize and quantify the distinct brain morphometry effects and latent dimensions across 8 neuropsychiatric CNVs. We analyzed T1-weighted MRI data from clinically and non-clinically ascertained CNV carriers (deletion/duplication) at the 1q21.1 (n = 39/28), 16p11.2 (n = 87/78), 22q11.2 (n = 75/30), and 15q11.2 (n = 72/76) loci as well as 1296 non-carriers (controls). Case-control contrasts of all examined genomic loci demonstrated effects on brain anatomy, with deletions and duplications showing mirror effects at the global and regional levels. Although CNVs mainly showed distinct brain patterns, principal component analysis (PCA) loaded subsets of CNVs on two latent brain dimensions, which explained 32 and 29% of the variance of the 8 Cohen’s d maps. The cingulate gyrus, insula, supplementary motor cortex, and cerebellum were identified by PCA and multi-view pattern learning as top regions contributing to latent dimension shared across subsets of CNVs. The large proportion of distinct CNV effects on brain morphology may explain the small neuroimaging effect sizes reported in polygenic psychiatric conditions. Nevertheless, latent gene brain morphology dimensions will help subgroup the rapidly expanding landscape of neuropsychiatric variants and dissect the heterogeneity of idiopathic conditions

Temporal examination of adult food insecurity amongst Canadian families managing food allergy

Pediatric food allergy is associated with excess familial food costs compared to families without allergy. Since the start of the COVID-19 pandemic, food prices have increased substantially. To understand the temporal pattern of food insecurity amongst Canadian families with food allergy from the year prior to the pandemic, through May 2022. Using data collected electronically from families reporting food allergy using a validated food security questionnaire, we estimated food insecurity, including categories of food insecurity (marginal, moderate, secure) in the year prior to the pandemic (2019; Wave 1), and the first (2020; Wave 2) and second years of the pandemic (2022; Wave 3). Participants in all waves were commonly in 2 + adult, 2 child households. Less than half of participants (Waves 1–3: 45.7%, 31.0%, and 22.9%, respectively) reported household incomes below the median Canadian. Common allergies were milk, eggs, peanuts and tree nuts. In Wave 1, 22.9% of families reported food insecurity; corresponding numbers at Waves 2 and 3 were 30.6% and 74.4%, respectively, representing an overall increase of 225.6%, including notable increases in severe food insecurity. Canadian families with pediatric food allergy report higher rates of food insecurity compared to the general Canadian population, especially during the pandemic.Medicine, Faculty ofNon UBCPediatrics, Department ofReviewedFacultyResearche