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HLA-B*27 was one of the first HLA alleles associated with an autoimmune disease, i.e., axial spondyloarthritis (axSpA) and acute anterior uveitis (B27AAU), which cause joint and eye inflammation, respectively. Gastrointestinal inflammation has been suggested as a trigger of axSpA. We recently identified a bacterial peptide (YeiH) that can be presented by HLA-B*27 to expanded public T cell receptors in the joint in axSpA and the eye in B27AAU. While YeiH is present in enteric microbiota and pathogens, additional evidence that pathogenic T cells in HLA-B*27-associated autoimmunity may have had a prior antigenic encounter within the gastrointestinal tract remains lacking. Here, we analyzed ocular, synovial, and blood T cells in B27AAU and axSpA, showing that YeiH-specific CD8+ T cells express a mucosal gene set and surface proteins consistent with intestinal differentiation, including CD161, integrin α4ß7, and CCR6. In addition, we found an expansion of YeiH-specific CD8+ T cells in axSpA and B27AAU blood compared with that from individuals acting as healthy controls, whereas influenza-specific CD8+ T cells were equivalent across groups. Finally, we demonstrated the dispensability of TRBV9 for antigen recognition. Collectively, our data suggest that, in HLA-B27-associated autoimmunity, early antigen exposure and differentiation of pathogenic CD8+ T cells may occur in enteric organs.
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Espondiloartrite Axial , Antígeno HLA-B27 , Receptores CCR6 , Uveíte Anterior , Humanos , Uveíte Anterior/imunologia , Antígeno HLA-B27/genética , Antígeno HLA-B27/imunologia , Receptores CCR6/genética , Receptores CCR6/metabolismo , Receptores CCR6/imunologia , Espondiloartrite Axial/imunologia , Feminino , Masculino , Adulto , Linfócitos T CD8-Positivos/imunologia , Integrinas/metabolismo , Integrinas/imunologia , Pessoa de Meia-IdadeRESUMO
Natural killer (NK) cells recognize target cells through germline-encoded activation and inhibitory receptors enabling effective immunity against viruses and cancer. The Ly49 receptor family in the mouse and killer immunoglobin-like receptor family in humans play a central role in NK cell immunity through recognition of MHC class I and related molecules. Functionally, these receptor families are involved in licensing and rejection of MHC-I-deficient cells through missing-self. The Ly49 family is highly polymorphic, making it challenging to detail the contributions of individual Ly49 receptors to NK cell function. Herein, we showed mice lacking expression of all Ly49s were unable to reject missing-self target cells in vivo, were defective in NK cell licensing, and displayed lower KLRG1 on the surface of NK cells. Expression of Ly49A alone on a H-2Dd background restored missing-self target cell rejection, NK cell licensing, and NK cell KLRG1 expression. Thus, a single inhibitory Ly49 receptor is sufficient to license NK cells and mediate missing-self in vivo.
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Comparative genomics has revealed the rapid expansion of multiple gene families involved in immunity. Members within each gene family often evolved distinct roles in immunity. However, less is known about the evolution of their epigenome and cis-regulation. Here we systematically profile the epigenome of the recently expanded murine Ly49 gene family that mainly encode either inhibitory or activating surface receptors on natural killer cells. We identify a set of cis-regulatory elements (CREs) for activating Ly49 genes. In addition, we show that in mice, inhibitory and activating Ly49 genes are regulated by two separate sets of proximal CREs, likely resulting from lineage-specific losses of CRE activity. Furthermore, we find that some Ly49 genes are cross-regulated by the CREs of other Ly49 genes, suggesting that the Ly49 family has begun to evolve a concerted cis-regulatory mechanism. Collectively, we demonstrate the different modes of cis-regulatory evolution for a rapidly expanding gene family.
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Evolução Molecular , Família Multigênica , Subfamília A de Receptores Semelhantes a Lectina de Células NK , Animais , Camundongos , Subfamília A de Receptores Semelhantes a Lectina de Células NK/genética , Subfamília A de Receptores Semelhantes a Lectina de Células NK/metabolismo , Sequências Reguladoras de Ácido Nucleico/genética , Regulação da Expressão Gênica , Células Matadoras Naturais/imunologia , Camundongos Endogâmicos C57BLRESUMO
Purpose: Uveitis is a heterogenous group of inflammatory eye disease for which current cytokine-targeted immune therapies are effective for only a subset of patients. We hypothesized that despite pathophysiologic nuances that differentiate individual disease states, all forms of eye inflammation might share common mechanisms for immune cell recruitment. Identifying these mechanisms is critical for developing novel, broadly acting therapeutic strategies. Design: Experimental study. Subjects: Biospecimens from patients with active or inactive uveitis and healthy controls. Methods: Protein concentration and single cell gene expression were assessed in aqueous fluid biopsies and plasma samples from deidentified patients with uveitis or healthy controls. Main Outcome Measures: The concentration of 31 inflammatory proteins was measured in all aqueous samples, as well as plasma samples from patients with active uveitis. Chemokine and cytokine ligand and receptor expression were assessed in individual cell types from aqueous biopsies obtained from patients with active uveitis. Results: We identified 6 chemokines that were both elevated in active uveitis compared with controls and enriched in aqueous compared with plasma during active uveitis (C-C motif chemokine ligand [CCL]2, C-X-C motif chemokine ligand [CXCL]10, CXCL9, CXCL8, CCL3, and CCL14), forming potential gradients for migration of immune cells from the blood to the eye. Of these, CCL2 and CXCL10 were consistently enriched in the aqueous of all patients in our cohort, as well as in a larger cohort of patients from a previously published study. These data suggest that CCL2 and CXCL10 are key mediators in immune cell migration to the eye during uveitis. Next, single cell RNA sequencing suggested that macrophages contribute to aqueous enrichment of CCL2 and CXCL10 during human uveitis. Finally, using chemokine ligand and receptor expression mapping, we identified a broad signaling network for macrophage-derived CCL2 and CXCL10 in human uveitis. Conclusions: These data suggest that ocular macrophages may play a central role, via CCL2 and CXCL10 production, in recruiting inflammatory cells to the eye in patients with uveitis. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
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On September 26th 2019, a major fire occurred in the Lubrizol factory located near the Seine estuary, in Rouen-France. Juvenile flounders were captured in the Canche estuary (a reference system) and caged one month in the Canche and in the Seine downstream the accident site. No significant increases of PAHs, PCBs and PFAS was detected in Seine vs Canche sediments after the accident, but a significant increase of dioxins and furans was observed in water and sewage sludge in the Rouen wastewater treatment plant. The proteomics approach highlighted a dysregulation of proteins associated with cholesterol synthesis and lipid metabolism, in fish caged in the Seine. The overall results suggested that the fire produced air borne dioxins and furans that got deposited on soil and subsequently entered in the Seine estuarine waters via runoff; thus contaminating fish preys and caged flounders in the Seine estuary.
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Dioxinas , Linguado , Poluentes Químicos da Água , Animais , Qualidade da Água , Monitoramento Ambiental/métodos , Linguado/metabolismo , Acidentes de Trabalho , Proteômica , França , Furanos/metabolismo , Poluentes Químicos da Água/análiseRESUMO
Both food insecurity and home and wild food procurement (HWFP), including gardening, increased in many countries during the COVID-19 pandemic; yet little evidence has demonstrated what impact HWFP had on food security. Using data from a representative sample of nearly 1000 residents in the two most rural US states (Vermont and Maine) conducted via an online survey in Spring/Summer 2021, as well as matching techniques, we compare food security outcomes among households who did and did not participate in HWFP in the first year of the pandemic. Nearly 60% of respondents engaged in HWFP in some way during the first year of the pandemic, with food insecure households more likely to do HWFP. Furthermore, HWFP early in the COVID-19 pandemic is associated with improved food security in the 9-12 months later, though these improvements were primarily associated with newly, not chronically, food insecure households. Newly and chronically food insecure households were more likely to want to continue these activities in the future, but also exhibited greater barriers to land access and costs associated with these activities. These results suggest that HWFP may provide food security improvements for certain households that utilize them, especially during crisis situations. Future research about HWFP should continue to explore multiple HWFP strategies, their barriers, and their potentially myriad relationships to food security, diet, and health outcomes, especially with longitudinal data.
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COVID-19 , Humanos , COVID-19/epidemiologia , Pandemias , Abastecimento de Alimentos , Alimentos , Segurança AlimentarRESUMO
Although pediatric growth curves provide clinical utility, using these metrics for within-person change over time can be misleading. As research is focused on understanding cardiometabolic consequences of weight gain, it is important to use precise metrics to analyze these longitudinal research questions. Despite several foundational recommendations to limit the use of reference pediatric growth curves (e.g., BMI z scores) for within-person longitudinal research, it has evolved into the "gold standard" for using growth curves for pediatric weight gain analyses. Therefore, the objective of this paper is to discuss (A) the methodology used to create reference growth curves; (B) the appropriate use of reference pediatric BMI growth curves within the context of cross-sectional and longitudinal analyses in research; and (C) how to select metrics based on desired evaluations. Careful consideration using standardized references scores is essential when assessing obesity-related questions and comorbid risk over time in pediatric populations.
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Obesidade , Aumento de Peso , Criança , Humanos , Índice de Massa Corporal , Estudos TransversaisRESUMO
Tissue-resident macrophages (TRMs) are long-lived cells that maintain locally and can be phenotypically distinct from monocyte-derived macrophages. Whether TRMs and monocyte-derived macrophages have district roles under differing pathologies is not understood. Here, we showed that a substantial portion of the macrophages that accumulated during pancreatitis and pancreatic cancer in mice had expanded from TRMs. Pancreas TRMs had an extracellular matrix remodeling phenotype that was important for maintaining tissue homeostasis during inflammation. Loss of TRMs led to exacerbation of severe pancreatitis and death, due to impaired acinar cell survival and recovery. During pancreatitis, TRMs elicited protective effects by triggering the accumulation and activation of fibroblasts, which was necessary for initiating fibrosis as a wound healing response. The same TRM-driven fibrosis, however, drove pancreas cancer pathogenesis and progression. Together, these findings indicate that TRMs play divergent roles in the pathogenesis of pancreatitis and cancer through regulation of stromagenesis.
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Pâncreas , Pancreatite , Camundongos , Animais , Pâncreas/patologia , Macrófagos , Pancreatite/genética , Pancreatite/patologia , Fibrose , Neoplasias PancreáticasRESUMO
This study aimed to develop a multidisciplinary approach to assess the ecological status of six moderate-sized French estuaries. For each estuary, we gathered geographical information, hydrobiological data, chemistry of pollutants and fish biology, including integration of proteomics and transcriptomics data. This integrative study covered the entire hydrological system studied, from the watershed to the estuary, and considered all the anthropogenic factors that can impact this environment. To reach this goal, European flounder (Platichthys flesus) were collected from six estuaries in September, which ensures a minimum residence time of five months within an estuary. Geographical metrics are used to characterize land use in each watershed. The concentrations of nitrite, nitrate, organic pollutants, and trace elements were measured in water, sediments and biota. All of these environmental parameters allowed to set up a typology of estuaries. Classical fish biomarkers, coupled with molecular data from transcriptomics and shotgun proteomics, highlighted the flounder's responses to stressors in its environment. We analysed the protein abundances and gene expression levels in the liver of fish from the different estuaries. We showed clear positive deregulation of proteins associated with xenobiotic detoxification in a system characterized by a large population density and industrial activity, as well as in a predominantly agricultural catchment area (mostly cultures of vegetables and pig breeding) mainly impacted by pesticides. Fish from the latter estuary also displayed strong deregulation of the urea cycle, most probably related to high nitrogen load. Proteomic and transcriptomic data also revealed a deregulation of proteins and genes related to the response to hypoxia, and a probable endocrine disruption in some estuaries. Coupling these data allowed the precise identification of the main stressors interacting within each hydrosystem.
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Linguado , Poluentes Químicos da Água , Animais , Suínos , Linguado/fisiologia , Monitoramento Ambiental , Ecossistema , Proteômica , França , Peixes/metabolismo , Estuários , Poluentes Químicos da Água/análiseRESUMO
The tissue-specific drivers of neurosarcoidosis remain poorly defined. To identify cerebrospinal fluid (CSF) specific, antigen-driven T and B cell responses, we performed single-cell RNA sequencing of CSF and blood cells from neurosarcoid participants coupled to T and B cell receptor sequencing. In contrast to pulmonary sarcoidosis, which is driven by CD4 T cells, we found CD8 T cell clonal expansion enriched in the neurosarcoid CSF. These CSF-enriched CD8 T cells were composed of two subsets with differential expression of EBI2, CXCR3, and CXCR4. Lastly, our data suggest that IFNγ signaling may distinguish neurosarcoidosis from other neurological disorders.
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Doenças do Sistema Nervoso Central , Sarcoidose , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Doenças do Sistema Nervoso Central/líquido cefalorraquidiano , Humanos , Sarcoidose/líquido cefalorraquidianoRESUMO
The main objective of this study was to improve our knowledge on the responses of fish populations to multistress (diffuse pollution and warming waters) in estuaries. Adult flounders were caught in two estuaries in the Eastern English Channel: the heavily polluted Seine estuary vs the moderately contaminated Canche estuary. Fish samplings were conducted in January just before the reproduction period, and in July when gonads were at rest. The overall rise in coastal winter water temperatures detected over the Channel impairs the flounder's phenology of reproduction in the two estuaries, inducing a delay of maturation process and probably also spawning. The higher liver histopathology index in Seine vs Canche could be the consequence of the fish exposition to a complex cocktail of contaminants in a strongly industrialized estuary. Higher levels of neurotoxicity, gill lipid peroxidation, and liver EROD activity were observed in Seine vs Canche. Furthermore, a possible impairment in mitochondrial metabolism was suggested in the Seine flounder population. We confirmed in this study the potential role of two membrane lipids (sphingomyelin and phosphatidylserine) in the resistance towards oxidative stress in Seine and Canche. Finally, we suggest that the Seine flounder population (and possibly the connected Eastern English Channel flounder populations over the French Coast) could be seriously impacted in the future by multistress: higher winter temperatures and chemical contamination.
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Linguado , Poluentes Químicos da Água , Animais , Mudança Climática , Monitoramento Ambiental , Estuários , Linguado/metabolismo , França , Estações do Ano , Poluentes Químicos da Água/análiseRESUMO
BACKGROUND: While opioid agonists represent the most efficacious treatment for opioid use disorder (OUD), they may enhance the reinforcing effects of sweets, placing individuals at risk for weight gain and associated consequences. We examined sucrose subjective response among adults receiving opioid agonist treatment vs. a comparison sample without OUD. METHODS: Forty adults with (OUD+) and 40 without OUD (OUD-) completed an intake battery of eating behaviors and body mass index. During two same-day sessions, participants sampled six experimenter-administered sucrose solutions (0, 0.10, 0.25, 0.50, 0.75, 1.0 M), each three times, under double-blind conditions and rated the pleasantness and intensity of each. RESULTS: OUD + participants presented with a higher prevalence of obesity and unhealthy eating behaviors vs. OUD- participants (p's < 0.05). They rated sucrose solutions as less pleasant than OUD- participants (p < 0.001), though this effect was limited to the three lowest concentrations (0, 0.10, 0.25M). There were no group differences on intensity ratings (p = 0.35). A change from baseline (placebo) analysis indicated a higher magnitude of change in pleasantness ratings and a lower magnitude of change in intensity ratings from 0M in OUD+ vs. OUD- (p's < 0.05). CONCLUSIONS: OUD+ participants exhibited a higher magnitude of change in pleasantness ratings from placebo vs. OUD-, which was largely driven by pronounced differences in perceived pleasantness of essentially unsweet solutions. OUD+ participants presented with a consistently more severe profile in regard to eating behaviors. These data highlight the risk factors experienced by OUD+ individuals that extend beyond drug-related risks and may inform future efforts to improve health outcomes.
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Comportamento Alimentar , Transtornos Relacionados ao Uso de Opioides , Sacarose , Adulto , Analgésicos Opioides/efeitos adversos , Humanos , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Resultado do TratamentoRESUMO
BACKGROUND: People who experience childhood sexual abuse (CSA) have a higher rate of adolescent pregnancy than people who do not experience CSA. The purpose of this integrative review was to identify risk or protective factors that are associated with this group to help understand the high rate of adolescent pregnancy in people with CSA histories. METHODS: This review was conducted using strategies described by Whittemore and Knafl (2005). Five research articles met the following criteria: written in English, published in peer-reviewed journals in the past 10 years, and included the examination of predictors of adolescent pregnancy in any domain of the social ecological model of individual, relationship, community, or societal factors present among girls with CSA histories. RESULTS: Studies suggest that people who are abused in childhood through adolescence and are not believed when they report abuse may be at greater risk for pregnancy in adolescence. CSA was associated with a range of sexual risk taking behavior (e.g., ineffectual contraception use, drug and alcohol use prior to sex, multiple partners) which could lead to adolescent pregnancy. Individual-level behaviors where predominantly studied. There were no reports at the community or societal level of the model. CONCLUSIONS: Identifying additional risk or protective factors at the relationship, community, and societal level may prove helpful in developing strategies tailored to this population. The unique characteristics that lead to higher rates of sexual risk-taking behavior that can lead to adolescent pregnancy have not been well documented and deserve further study to guide design and prevention/intervention modalities.
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Abuso Sexual na Infância , Maus-Tratos Infantis , Gravidez na Adolescência , Adolescente , Criança , Feminino , Humanos , Gravidez , Assunção de Riscos , Comportamento SexualRESUMO
Multimodal neuroimaging assessments were utilized to identify generalizable brain correlates of current body mass index (BMI) and predictors of pathological weight gain (i.e., beyond normative development) one year later. Multimodal data from children enrolled in the Adolescent Brain Cognitive Development Study® at 9-to-10-years-old, consisted of structural magnetic resonance imaging (MRI), diffusion tensor imaging (DTI), resting state (rs), and three task-based functional (f) MRI scans assessing reward processing, inhibitory control, and working memory. Cross-validated elastic-net regression revealed widespread structural associations with BMI (e.g., cortical thickness, surface area, subcortical volume, and DTI), which explained 35% of the variance in the training set and generalized well to the test set (R2 = 0.27). Widespread rsfMRI inter- and intra-network correlations were related to BMI (R2train = 0.21; R2test = 0.14), as were regional activations on the working memory task (R2train = 0.20; (R2test = 0.16). However, reward and inhibitory control tasks were unrelated to BMI. Further, pathological weight gain was predicted by structural features (Area Under the Curve (AUC)train = 0.83; AUCtest = 0.83, p < 0.001), but not by fMRI nor rsfMRI. These results establish generalizable brain correlates of current weight and future pathological weight gain. These results also suggest that sMRI may have particular value for identifying children at risk for pathological weight gain.
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Encéfalo , Imagem de Tensor de Difusão , Adolescente , Encéfalo/diagnóstico por imagem , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Neuroimagem , Aumento de PesoRESUMO
Climate change, along with environmental pollution, can act synergistically on an organism to amplify adverse effects of exposure. The Arctic is undergoing profound climatic change and an increase in human activity, resulting in a heightened risk of accidental oil spills. Embryos and larvae of polar cod (Boreogadus saida), a key Arctic forage fish species, were exposed to low levels of crude oil concurrently with a 2.3 °C increase in water temperature. Here we show synergistic adverse effects of increased temperature and crude oil exposure on early life stages documented by an increased prevalence of malformations and mortality in exposed larvae. The combined effects of these stressors were most prevalent in the first feeding larval stages despite embryonic exposure, highlighting potential long-term consequences of exposure for survival, growth, and reproduction. Our findings suggest that a warmer Arctic with greater human activity will adversely impact early life stages of this circumpolar forage fish.
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Embrião não Mamífero/citologia , Larva/crescimento & desenvolvimento , Poluição por Petróleo/efeitos adversos , Petróleo/toxicidade , Temperatura , Poluentes Químicos da Água/toxicidade , Animais , Regiões Árticas , Mudança Climática , Embrião não Mamífero/efeitos dos fármacos , Gadiformes , Larva/efeitos dos fármacos , Petróleo/análise , Poluição por Petróleo/análise , Testes de Toxicidade , Poluentes Químicos da Água/análiseRESUMO
Objective: To identify molecular features that distinguish individuals with shared clinical features of granulomatous uveitis. Design: Cross-sectional, observational study. Participants: Four eyes from patients with active granulomatous uveitis. Methods: We performed single-cell RNA-sequencing with antigen-receptor sequence analysis to obtain an unbiased gene expression survey of ocular immune cells and identify clonally expanded lymphocytes. Main Outcomes Measures: For each inflamed eye, we measured the proportion of distinct immune cell types, the amount of B or T cell clonal expansion, and the transcriptional profile of T and B cells. Results: Each individual had robust clonal expansion arising from a single T or B cell lineage, suggesting distinct, antigen-driven pathogenic processes in each patient. This variability in clonal expansion was mirrored by individual variability in CD4 T cell populations, whereas ocular CD8 T cells and B cells were more transcriptionally similar between patients. Finally, ocular B cells displayed evidence of class-switching and plasmablast differentiation within the ocular microenvironment, providing additional support for antigen-driven immune responses in granulomatous uveitis. Conclusions: Collectively, our study identified both conserved and individualized features of granulomatous uveitis, illuminating parallel pathophysiologic mechanisms, and suggesting that future personalized therapeutic approaches may be warranted.
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The prevalence of obesity in children and adolescents worldwide has quadrupled since 1975 and is a key predictor of obesity later in life. Previous work has consistently observed relationships between macroscale measures of reward-related brain regions (e.g., the nucleus accumbens [NAcc]) and unhealthy eating behaviors and outcomes; however, the mechanisms underlying these associations remain unclear. Recent work has highlighted a potential role of neuroinflammation in the NAcc in animal models of diet-induced obesity. Here, we leverage a diffusion MRI technique, restriction spectrum imaging, to probe the microstructure (cellular density) of subcortical brain regions. More specifically, we test the hypothesis that the cell density of reward-related regions is associated with obesity-related metrics and early weight gain. In a large cohort of nine- and ten-year-olds enrolled in the Adolescent Brain Cognitive Development (ABCD) study, we demonstrate that cellular density in the NAcc is related to individual differences in waist circumference at baseline and is predictive of increases in waist circumference after 1 y. These findings suggest a neurobiological mechanism for pediatric obesity consistent with rodent work showing that high saturated fat diets increase gliosis and neuroinflammation in reward-related brain regions, which in turn lead to further unhealthy eating and obesity.
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Núcleo Accumbens/citologia , Obesidade Infantil/etiologia , Circunferência da Cintura , Aumento de Peso , Contagem de Células , Criança , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Masculino , Núcleo Accumbens/diagnóstico por imagem , Obesidade Infantil/diagnóstico por imagemRESUMO
OBJECTIVE: To objectively determine the prevalence of overweight and obesity in elementary school children in two rural counties in Vermont prior to implementing a community-based intervention. METHODS: School-based objective measures of body mass index (BMI) were obtained from 1,688 public school children in first, third, and fifth grades in two Northern Vermont counties in the Fall of 2017. RESULTS: Forty-one percentage of elementary school children were either overweight or obese, nearly double the estimated Vermont prevalence rate of 22.2%. Schools located in more rural areas showed higher levels of overweight and obesity in children than schools in less rural areas in these northern counties (p < .005). CONCLUSIONS: Indirect and self-reported measures of BMI may be underestimating the true prevalence of overweight and obesity particularly in more rural communities. POLICY IMPLICATIONS: Data presented here in which children were measured directly by trained study staff demonstrate that the prevalence of obesity among children in elementary school is alarmingly high. Accurate, ongoing BMI measurement surveillance is one tool to better understand both the current trends in childhood overweight and obesity and the effect of community and state interventions.
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Obesidade Infantil/epidemiologia , Índice de Massa Corporal , Criança , Feminino , Humanos , Masculino , Prevalência , População Rural/estatística & dados numéricos , Instituições Acadêmicas , Vermont/epidemiologiaRESUMO
Major histocompatibility complex class I (MHC-I)-restricted immune responses are largely attributed to cytotoxic T lymphocytes (CTLs). However, natural killer (NK) cells, as predicted by the missing-self hypothesis, have opposing requirements for MHC-I, suggesting that they may also demonstrate MHC-I-restricted effects. In mice, the Ly49 inhibitory receptors prevent NK cell killing of missing-self targets in effector responses, and they have a proposed second function in licensing or educating NK cells via self-MHC-I in vivo. Here we show MHC-I-restricted control of murine cytomegalovirus (MCMV) infection in vivo that is NK cell dependent. Using mice lacking specific Ly49 receptors, we show that control of MCMV requires inhibitory Ly49 receptors and an inhibitory signaling motif and the capacity for MCMV to downregulate MHC-I. Taken together, these data provide definitive evidence that the inhibitory receptors are required for missing-self rejection and are relevant to MHC-I-restricted NK cell control of a viral infection in vivo.
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Antígenos de Histocompatibilidade Classe I/metabolismo , Células Matadoras Naturais/metabolismo , Subfamília A de Receptores Semelhantes a Lectina de Células NK/metabolismo , Animais , Antígenos Ly , Infecções por Citomegalovirus/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Células Matadoras Naturais/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Muromegalovirus/imunologia , Muromegalovirus/patogenicidade , Subfamília A de Receptores Semelhantes a Lectina de Células NK/imunologia , Receptores de Células Matadoras Naturais , VirosesRESUMO
Recognition of DNA viruses, such as cytomegaloviruses (CMVs), through pattern-recognition receptor (PRR) pathways involving MyD88 or STING constitute a first-line defense against infections mainly through production of type I interferon (IFN-I). However, the role of these pathways in different tissues is incompletely understood, an issue particularly relevant to the CMVs which have broad tissue tropisms. Herein, we contrasted anti-viral effects of MyD88 versus STING in distinct cell types that are infected with murine CMV (MCMV). Bone marrow chimeras revealed STING-mediated MCMV control in hematological cells, similar to MyD88. However, unlike MyD88, STING also contributed to viral control in non-hematological, stromal cells. Infected splenic stromal cells produced IFN-I in a cGAS-STING-dependent and MyD88-independent manner, while we confirmed plasmacytoid dendritic cell IFN-I had inverse requirements. MCMV-induced natural killer cytotoxicity was dependent on MyD88 and STING. Thus, MyD88 and STING contribute to MCMV control in distinct cell types that initiate downstream immune responses.