41 research outputs found

    Dengue Virus Infection and Virus-Specific HLA-A2 Restricted Immune Responses in Humanized NOD-scid IL2rγnull Mice

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    BACKGROUND:The lack of a suitable animal model to study viral and immunological mechanisms of human dengue disease has been a deterrent to dengue research. METHODOLOGY/PRINCIPAL FINDINGS:We sought to establish an animal model for dengue virus (DENV) infection and immunity using non-obese diabetic/severe combined immunodeficiency interleukin-2 receptor gamma-chain knockout (NOD-scid IL2rgamma(null)) mice engrafted with human hematopoietic stem cells. Human CD45(+) cells in the bone marrow of engrafted mice were susceptible to in vitro infection using low passage clinical and established strains of DENV. Engrafted mice were infected with DENV type 2 by different routes and at multiple time points post infection, we detected DENV antigen and RNA in the sera, bone marrow, spleen and liver of infected engrafted mice. Anti-dengue IgM antibodies directed against the envelope protein of DENV peaked in the sera of mice at 1 week post infection. Human T cells that developed following engraftment of HLA-A2 transgenic NOD-scid IL2rgamma(null) mice with HLA-A2(+) human cord blood hematopoietic stem cells, were able to secrete IFN-gamma, IL-2 and TNF-alpha in response to stimulation with three previously identified A2 restricted dengue peptides NS4b 2353((111-119)), NS4b 2423((181-189)), and NS4a 2148((56-64)). CONCLUSIONS/SIGNIFICANCE:This is the first study to demonstrate infection of human cells and functional DENV-specific T cell responses in DENV-infected humanized mice. Overall, these mice should be a valuable tool to study the role of prior immunity on subsequent DENV infections

    A Non Mouse-Adapted Dengue Virus Strain as a New Model of Severe Dengue Infection in AG129 Mice

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    The spread of dengue (DEN) worldwide combined with an increased severity of the DEN-associated clinical outcomes have made this mosquito-borne virus of great global public health importance. Progress in understanding DEN pathogenesis and in developing effective treatments has been hampered by the lack of a suitable small animal model. Most of the DEN clinical isolates and cell culture-passaged DEN virus strains reported so far require either host adaptation, inoculation with a high dose and/or intravenous administration to elicit a virulent phenotype in mice which results, at best, in a productive infection with no, few, or irrelevant disease manifestations, and with mice dying within few days at the peak of viremia. Here we describe a non-mouse-adapted DEN2 virus strain (D2Y98P) that is highly infectious in AG129 mice (lacking interferon-α/β and -γ receptors) upon intraperitoneal administration. Infection with a high dose of D2Y98P induced cytokine storm, massive organ damage, and severe vascular leakage, leading to haemorrhage and rapid death of the animals at the peak of viremia. In contrast, very interestingly and uniquely, infection with a low dose of D2Y98P led to asymptomatic viral dissemination and replication in relevant organs, followed by non-paralytic death of the animals few days after virus clearance, similar to the disease kinetic in humans. Spleen damage, liver dysfunction and increased vascular permeability, but no haemorrhage, were observed in moribund animals, suggesting intact vascular integrity, a cardinal feature in DEN shock syndrome. Infection with D2Y98P thus offers the opportunity to further decipher some of the aspects of dengue pathogenesis and provides a new platform for drug and vaccine testing

    CropPol: a dynamic, open and global database on crop pollination

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    This is the final version. Available from Wiley via the DOI in this record The original dataset (v1.1.0) of the CropPol database can be accessed from the ECOLOGY repository. Main upgrades of these datasets will be versioned and deposited in Zenodo (DOI: 10.5281/zenodo.5546600)Data availability. V.C. Computer programs and data-processing algorithms: The algorithms used in deriving, processing, or transforming data can be accessed in the DataS1.zip file and the Zenodo repository (DOI: 10.5281/zenodo.5546600). V.D. Archiving: The data is archived for long-term storage and access in Zenodo (DOI: 10.5281/zenodo.5546600)Seventy five percent of the world's food crops benefit from insect pollination. Hence, there has been increased interest in how global change drivers impact this critical ecosystem service. Because standardized data on crop pollination are rarely available, we are limited in our capacity to understand the variation in pollination benefits to crop yield, as well as to anticipate changes in this service, develop predictions, and inform management actions. Here, we present CropPol, a dynamic, open and global database on crop pollination. It contains measurements recorded from 202 crop studies, covering 3,394 field observations, 2,552 yield measurements (i.e. berry weight, number of fruits and kg per hectare, among others), and 47,752 insect records from 48 commercial crops distributed around the globe. CropPol comprises 32 of the 87 leading global crops and commodities that are pollinator dependent. Malus domestica is the most represented crop (32 studies), followed by Brassica napus (22 studies), Vaccinium corymbosum (13 studies), and Citrullus lanatus (12 studies). The most abundant pollinator guilds recorded are honey bees (34.22% counts), bumblebees (19.19%), flies other than Syrphidae and Bombyliidae (13.18%), other wild bees (13.13%), beetles (10.97%), Syrphidae (4.87%), and Bombyliidae (0.05%). Locations comprise 34 countries distributed among Europe (76 studies), Northern America (60), Latin America and the Caribbean (29), Asia (20), Oceania (10), and Africa (7). Sampling spans three decades and is concentrated on 2001-05 (21 studies), 2006-10 (40), 2011-15 (88), and 2016-20 (50). This is the most comprehensive open global data set on measurements of crop flower visitors, crop pollinators and pollination to date, and we encourage researchers to add more datasets to this database in the future. This data set is released for non-commercial use only. Credits should be given to this paper (i.e., proper citation), and the products generated with this database should be shared under the same license terms (CC BY-NC-SA). This article is protected by copyright. All rights reserved.OBServ Projec

    Efeitos da Reeducação Postural Global em escolares com escoliose Global Posture Reeducation effects in students with scoliosis

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    O objetivo deste estudo foi analisar o efeito do método da Reeducação Postural Global (RPG) em escolares com diagnóstico de escoliose torácica não estrutural (ETNE). Os escolares com indicativo de ETNE ao exame postural e teste de Adams negativo foram encaminhados ao exame radiográfico para comprovação diagnóstica. Foram selecionados 20 participantes (11 meninos e 9 meninas, com 10±3 anos), divididos randomicamente em dois grupos homogêneos: o que realizou o RPG (GRPG) durante 12 semanas com duração de 25 a 30 minutos cada sessão, de acordo com o que aguentou permanecer na postura; e o grupo controle (GC), sem intervenção. Após três meses, os dois grupos repetiram a avaliação postural e o exame radiográfico. Para avaliação das estatísticas, foi utilizada análise de variância (ANOVA) univariada, com medidas repetidas, seguida do Post Hoc de Tukey para identificar as possíveis diferenças intra e intergrupos. O valor de &#945; foi de 0,05. O GRPG apresentou redução significativa no ângulo de Cobb na comparação intragrupo (&#916;%=-35,100; p=0,009), mas o GC não (&#916;%=9,520; p=0,789). Pode-se concluir que escolares submetidos ao método da RPG apresentaram melhora do quadro de escoliose torácica não estrutural.<br>The aim of this study was to analyze the effect of Global Reeducation Postural (RPG) method in scholars diagnosed with thoracic nonstructural scoliosis (ETNE). Scholars with indicative of ETNE to postural exam and Adams test negative were directed to radiographic exam to diagnostic. Twenty participants were selected (11 boys and 9 girls, 10±3 years old) and randomly divided in two homogeneous groups: group treated by RPG (GRPG) and control group (CG). The GRPG was submitted a RPG treatment during 12 weeks in sessions from 25 to 30 minutes in agreement with each student tolerance at posture. The CG didn't suffer intervention. After three months, both groups repeated the postural and radiographic exam. For statistics, it was used ANOVA univariated with repeated measures, followed by Tukey Post Hoc Test to identify the possible differences intra and intergroups. The &#945; value used was 0.05. The GRPG present significant reduction at Cobb angle between pre and posttest (&#916;%=-35.100; p=0.009), but the CG didn´t show (&#916;%=9.520; p=0.789). It was concluded that scholars submitted to RPG method presented improvement in thoracic nonstructural scoliosis
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