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1.
Proc Natl Acad Sci U S A ; 121(34): e2322063121, 2024 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-39136989

RESUMO

Global migrations of diverse animal species often converge along the same routes, bringing together seasonal assemblages of animals that may compete, prey on each other, and share information or pathogens. These interspecific interactions, when energetic demands are high and the time to complete journeys is short, may influence survival, migratory success, stopover ecology, and migratory routes. Numerous accounts suggest that interspecific co-migrations are globally distributed in aerial, aquatic, and terrestrial systems, although the study of migration to date has rarely investigated species interactions among migrating animals. Here, we test the hypothesis that migrating animals are communities engaged in networks of ecological interactions. We leverage over half a million records of 50 bird species from five bird banding sites collected over 8 to 23 y to test for species associations using social network analyses. We find strong support for persistent species relationships across sites and between spring and fall migration. These relationships may be ecologically meaningful: They are often stronger among phylogenetically related species with similar foraging behaviors and nonbreeding ranges even after accounting for the nonsocial contributions to associations, including overlap in migration timing and habitat use. While interspecific interactions could result in costly competition or beneficial information exchange, we find that relationships are largely positive, suggesting limited competitive exclusion at the scale of a banding station during migratory stopovers. Our findings support an understanding of animal migrations that consist of networked communities rather than random assemblages of independently migrating species, encouraging future studies of the nature and consequences of co-migrant interactions.


Assuntos
Migração Animal , Aves , Ecossistema , Estações do Ano , Animais , Migração Animal/fisiologia , Aves/fisiologia
2.
J Gen Virol ; 103(3)2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35353676

RESUMO

Intraspecific variation in pathogen shedding impacts disease transmission dynamics; therefore, understanding the host factors associated with individual variation in pathogen shedding is key to controlling and preventing outbreaks. In this study, ileum and bursa of Fabricius tissues of wild-bred mallards (Anas platyrhynchos) infected with low-pathogenic avian influenza (LPAIV) were evaluated at various post-infection time points to determine genetic host factors associated with intraspecific variation in viral shedding. By analysing transcriptome sequencing data (RNA-seq), we found that LPAIV-infected wild-bred mallards do not exhibit differential gene expression compared to uninfected birds, but that gene expression was associated with cloacal viral shedding quantity early in the infection. In both tissues, immune gene expression was higher in high/moderate shedding birds compared to low shedding birds, and significant positive relationships with viral shedding were observed. In the ileum, expression for host genes involved in viral cell entry was lower in low shedders compared to moderate shedders at 1 day post-infection (DPI), and expression for host genes promoting viral replication was higher in high shedders compared to low shedders at 2 DPI. Our findings indicate that viral shedding is a key factor for gene expression differences in LPAIV-infected wild-bred mallards, and the genes identified in this study could be important for understanding the molecular mechanisms driving intraspecific variation in pathogen shedding.


Assuntos
Vírus da Influenza A , Influenza Aviária , Animais , Patos , Expressão Gênica , Vírus da Influenza A/genética , Eliminação de Partículas Virais
3.
BMC Vet Res ; 16(1): 430, 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33167978

RESUMO

BACKGROUND: Individual heterogeneity in pathogen load can affect disease transmission dynamics; therefore, identifying intrinsic factors responsible for variation in pathogen load is necessary for determining which individuals are prone to be most infectious. Because low pathogenic avian influenza viruses (LPAIV) preferentially bind to alpha-2,3 sialic acid receptors (SAα2,3Gal) in the intestines and bursa of Fabricius in wild ducks (Anas and Spatula spp.), we investigated juvenile mallards (Anas platyrhyncos) and blue-winged teals (Anas discors) orally inoculated with A/northern pintail/California/44221-761/2006 (H5N9) and the virus titer relationship to occurrence frequency of SAα2,3Gal in the intestines and bursa. To test the natural variation of free-ranging duck populations, birds were hatched and raised in captivity from eggs collected from nests of free-ranging birds in North Dakota, USA. Data generated from qPCR were used to quantify virus titers in cloacal swabs, ileum tissue, and bursa of Fabricius tissue, and lectin histochemistry was used to quantify the occurrence frequency of SAα2,3Gal. Linear mixed models were used to analyze infection status, species, and sex-based differences. Multiple linear regression was used to analyze the relationship between virus titer and SAα2,3Gal occurrence frequency. RESULTS: In mallards, we found high individual variation in virus titers significantly related to high variation of SAα2,3Gal in the ileum. In contrast to mallards, individual variation in teals was minimal and significant relationships between virus titers and SAα2,3Gal were not determined. Collectively, teals had both higher virus titers and a higher occurrence frequency of SAα2,3Gal compared to mallards, which may indicate a positive association between viral load and SAα2,3Gal. Statistically significant differences were observed between infected and control birds indicating that LPAIV infection may influence the occurrence frequency of SAα2,3Gal, or vice versa, but only in specific tissues. CONCLUSIONS: The results of this study provide quantitative evidence that SAα2,3Gal abundance is related to LPAIV titers; thus, SAα2,3Gal should be considered a potential intrinsic factor influencing variation in LPAIV load.


Assuntos
Vírus da Influenza A/metabolismo , Influenza Aviária/virologia , Receptores de Superfície Celular/metabolismo , Carga Viral/veterinária , Animais , Bolsa de Fabricius/virologia , Patos , Feminino , Vírus da Influenza A/fisiologia , Intestinos/virologia , Masculino , Especificidade da Espécie
4.
EMBO J ; 34(7): 881-95, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25666591

RESUMO

Intestinal immune regulatory signals govern gut homeostasis. Breakdown of such regulatory mechanisms may result in inflammatory bowel disease (IBD). Lactobacillus acidophilus contains unique surface layer proteins (Slps), including SlpA, SlpB, SlpX, and lipoteichoic acid (LTA), which interact with pattern recognition receptors to mobilize immune responses. Here, to elucidate the role of SlpA in protective immune regulation, the NCK2187 strain, which solely expresses SlpA, was generated. NCK2187 and its purified SlpA bind to the C-type lectin SIGNR3 to exert regulatory signals that result in mitigation of colitis, maintenance of healthy gastrointestinal microbiota, and protected gut mucosal barrier function. However, such protection was not observed in Signr3(-/-) mice, suggesting that the SlpA/SIGNR3 interaction plays a key regulatory role in colitis. Our work presents critical insights into SlpA/SIGNR3-induced responses that are integral to the potential development of novel biological therapies for autoinflammatory diseases, including IBD.


Assuntos
Antígenos CD/imunologia , Proteínas de Bactérias/imunologia , Doenças Inflamatórias Intestinais/imunologia , Mucosa Intestinal/imunologia , Lactobacillus acidophilus/imunologia , Lectinas Tipo C/imunologia , Animais , Antígenos CD/genética , Proteínas de Bactérias/genética , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/microbiologia , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/patologia , Lactobacillus acidophilus/genética , Lectinas Tipo C/genética , Lipopolissacarídeos/genética , Lipopolissacarídeos/imunologia , Camundongos , Camundongos Knockout , Ligação Proteica/genética , Ligação Proteica/imunologia , Ácidos Teicoicos/genética , Ácidos Teicoicos/imunologia
5.
Bioessays ; 39(3)2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28009049

RESUMO

Skin pigment pattern formation is a paradigmatic example of pattern formation. In zebrafish, the adult body stripes are generated by coordinated rearrangement of three distinct pigment cell-types, black melanocytes, shiny iridophores and yellow xanthophores. A stem cell origin of melanocytes and iridophores has been proposed although the potency of those stem cells has remained unclear. Xanthophores, however, seemed to originate predominantly from proliferation of embryonic xanthophores. Now, data from Singh et al. shows that all three cell-types derive from shared stem cells, and that these cells generate peripheral neural cell-types too. Furthermore, clonal compositions are best explained by a progressive fate restriction model generating the individual cell-types. The numbers of adult pigment stem cells associated with the dorsal root ganglia remain low, but progenitor numbers increase significantly during larval development up to metamorphosis, likely via production of partially restricted progenitors on the spinal nerves.


Assuntos
Crista Neural , Peixe-Zebra/embriologia , Animais , Metamorfose Biológica , Pigmentação , Células-Tronco
6.
Appetite ; 136: 124-129, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30690053

RESUMO

Attending to food being eaten ('attentive eating') may reduce later overeating. However, evidence in support of this comes primarily from studies in women. The aims of the current study were to investigate the effect that attentive eating has on later food intake in men and examine potential underlying mechanisms. Using a within-subjects design, 34 men (BMI M = 23.73 kg/m2, SD = 2.93; age M = 29.15, SD = 11.99) consumed a fixed lunchtime meal on two study days. On one study day participants were instructed to pay attention to the sensory properties of the meal as they ate (focused attention condition), and on the other study day participants ate lunch normally. Three hours after each lunchtime session, ad libitum consumption of snack food was measured, and measures of memory for the earlier lunchtime meal were completed. Participants remembered the lunch to be significantly more satiating in the focused attention condition compared to the control condition. However, focused attention did not significantly affect later ad libitum snack intake or other measures of meal memory. Further research is needed to understand when focused attention influences subsequent food intake before this approach can be used effectively to reduce food intake.


Assuntos
Atenção/fisiologia , Comportamento Alimentar/psicologia , Memória/fisiologia , Saciação/fisiologia , Lanches/psicologia , Adolescente , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
Semin Cell Dev Biol ; 49: 44-51, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26709005

RESUMO

The gastrointestinal (GI) tract must balance the extraction of energy and metabolic end-products from ingested nutrition and resident gut microbes and the maintenance of a symbiotic relationship with this microbiota, with the ability to mount functional immune responses to pathogenic organisms to maintain GI health. The gut epithelium is equipped with bacteria-sensing mechanisms that discriminate between pathogenic and commensal microorganisms and regulate host responses between immunity and tolerance. The epithelium also expresses numerous nutrient-sensing receptors, but their importance in the preservation of the gut microbiota and immune homeostasis remains largely unexplored. Observations that a deficiency in the extracellular calcium-sensing receptor (CaSR) using intestinal epithelium-specific receptor knockout mice resulted in diminished intestinal barrier integrity, altered composition of the gut microbiota, modified expression of intestinal pattern recognition receptors, and a skewing of local and systemic innate responses from regulatory to stimulatory, may change the way that this receptor is considered as a potential immunotherapeutic target in gut homeostasis. These findings suggest that pharmacologic CaSR activators and CaSR-based nutrients such as calcium, polyamines, phenylalanine, tryptophan, and oligo-peptides might be useful in conditioning the gut microenvironment, and thus, in the prevention and treatment of disorders such as inflammatory bowel disease (IBD), infectious enterocolitis, and other inflammatory and secretory diarrheal diseases. Here, we review the emerging roles of the CaSR in intestinal homeostasis and its therapeutic potential for gut pathology.


Assuntos
Colite/imunologia , Trato Gastrointestinal/imunologia , Receptores de Detecção de Cálcio/fisiologia , Animais , Colite/metabolismo , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/metabolismo , Diarreia/imunologia , Diarreia/metabolismo , Trato Gastrointestinal/metabolismo , Humanos , Doenças Inflamatórias Intestinais , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Transdução de Sinais
8.
FASEB J ; 30(4): 1683-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26728177

RESUMO

Academic achievement in adolescents is correlated with 1-carbon metabolism (1-CM), as folate intake is positively related and total plasma homocysteine (tHcy) negatively related to academic success. Because another 1-CM nutrient, choline is essential for fetal neurocognitive development, we hypothesized that choline and betaine could also be positively related to academic achievement in adolescents. In a sample of 15-yr-old children (n= 324), we measured plasma concentrations of homocysteine, choline, and betaine and genotyped them for 2 polymorphisms with effects on 1-CM, methylenetetrahydrofolate reductase (MTHFR) 677C>T, rs1801133, and phosphatidylethanolamineN-methyltransferase (PEMT), rs12325817 (G>C). The sum of school grades in 17 major subjects was used as an outcome measure for academic achievement. Lifestyle and family socioeconomic status (SES) data were obtained from questionnaires. Plasma choline was significantly and positively associated with academic achievement independent of SES factors (paternal education and income, maternal education and income, smoking, school) and of folate intake (P= 0.009,R(2)= 0.285). With the addition of thePEMTrs12325817 polymorphism, the association value was only marginally changed. Plasma betaine concentration, tHcy, and theMTHFR677C>T polymorphism did not affect academic achievement in any tested model involving choline. Dietary intake of choline is marginal in many adolescents and may be a public health concern.-Nilsson, T. K., Hurtig-Wennlöf, A., Sjöström, M., Herrmann, W., Obeid, R., Owen, J. R., Zeisel, S. Plasma 1-carbon metabolites and academic achievement in 15-yr-old adolescents.


Assuntos
Betaína/sangue , Colina/sangue , Escolaridade , Homocisteína/sangue , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Fosfatidiletanolamina N-Metiltransferase/genética , Adolescente , Estudos Transversais , Feminino , Genótipo , Humanos , Modelos Lineares , Masculino , Polimorfismo de Nucleotídeo Único , Classe Social , Inquéritos e Questionários
9.
Physiol Genomics ; 48(7): 526-36, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27235450

RESUMO

Hypertension (HTN) is a prevalent condition with complex etiology and pathophysiology. Evidence exists of significant communication between the nervous system and the immune system (IS), and there appears to be a direct role for inflammatory bone marrow (BM) cells in the pathophysiology of hypertension. However, the molecular and neural mechanisms underlying this interaction have not been characterized. Here, we transplanted whole BM cells from the beta 1 and 2 adrenergic receptor (AdrB1(tm1Bkk)AdrB2(tm1Bkk)/J) knockout (KO) mice into near lethally irradiated C57BL/6J mice to generate a BM AdrB1.B2 KO chimera. This allowed us to evaluate the role of the BM beta 1 and beta 2 adrenergic receptors in mediating BM IS homeostasis and regulating blood pressure (BP) in an otherwise intact physiological setting. Fluorescence-activated cell sorting demonstrated that a decrease in systolic and mean BP in the AdrB1.B2 KO chimera is associated with a decrease in circulating inflammatory T cells, macrophage/monocytes, and neutrophils. Transcriptomics in the BM identified 7,419 differentially expressed transcripts between the C57 and AdrB1.B2 KO chimera. Pathway analysis revealed differentially expressed transcripts related to several cell processes in the BM of C57 compared with AdrB1.B2 KO chimera, including processes related to immunity (e.g., T-cell activation, T-cell recruitment, cytokine production, leukocyte migration and function), the cardiovascular system (e.g., blood vessel development, peripheral nerve blood flow), and the brain (e.g., central nervous system development, neurite development) among others. This study generates new insight into the molecular events that underlie the interaction between the sympathetic drive and IS in modulation of BP.


Assuntos
Pressão Sanguínea/genética , Medula Óssea/metabolismo , Redes Reguladoras de Genes/genética , Inflamação/genética , Receptores Adrenérgicos beta 1/genética , Receptores Adrenérgicos beta 2/genética , Transcrição Gênica/genética , Animais , Células da Medula Óssea/metabolismo , Transplante de Medula Óssea/métodos , Modelos Animais de Doenças , Hipertensão/genética , Hipertensão/metabolismo , Inflamação/metabolismo , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/metabolismo , Neutrófilos/metabolismo
10.
FASEB J ; 29(8): 3426-35, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25921832

RESUMO

Choline is an essential nutrient, and the amount needed in the diet is modulated by several factors. Given geographical differences in dietary choline intake and disparate frequencies of single-nucleotide polymorphisms (SNPs) in choline metabolism genes between ethnic groups, we tested the hypothesis that 3 SNPs that increase dependence on dietary choline would be under negative selection pressure in settings where choline intake is low: choline dehydrogenase (CHDH) rs12676, methylenetetrahydrofolate reductase 1 (MTHFD1) rs2236225, and phosphatidylethanolamine-N-methyltransferase (PEMT) rs12325817. Evidence of negative selection was assessed in 2 populations: one in The Gambia, West Africa, where there is historic evidence of a choline-poor diet, and the other in the United States, with a comparatively choline-rich diet. We used 2 independent methods, and confirmation of our hypothesis was sought via a comparison with SNP data from the Maasai, an East African population with a genetic background similar to that of Gambians but with a traditional diet that is higher in choline. Our results show that frequencies of SNPs known to increase dependence on dietary choline are significantly reduced in the low-choline setting of The Gambia. Our findings suggest that adequate intake levels of choline may have to be reevaluated in different ethnic groups and highlight a possible approach for identifying novel functional SNPs under the influence of dietary selective pressure.


Assuntos
Colina/genética , Colina/metabolismo , Etnicidade/genética , Polimorfismo de Nucleotídeo Único/genética , Colina Desidrogenase/genética , Colina Desidrogenase/metabolismo , Dieta/métodos , Feminino , Genótipo , Humanos , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/metabolismo , Fosfatidiletanolamina N-Metiltransferase/genética , Fosfatidiletanolamina N-Metiltransferase/metabolismo
11.
J Appl Clin Med Phys ; 17(5): 222-234, 2016 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-27685135

RESUMO

A new megavoltage (MV) energy was recently introduced on Varian TrueBeam linear accelerators for imaging applications. This work describes the experimental characterization of a 2.5 MV inline portal imaging beam for commissioning, routine clinical use, and quality assurance purposes. The beam quality of the 2.5 MV beam was determined by measuring a percent depth dose, PDD, in water phantom for 10 × 10 cm2 field at source-to-surface distance 100 cm with a CC13 ion chamber, plane parallel Markus chamber, and GafChromic EBT3 film. Absolute dosimetric output calibration of the beam was performed using a traceable calibrated ionization chamber, following the AAPM Task Group 51 procedure. EBT3 film measurements were also performed to measure entrance dose. The output stability of the imaging beam was monitored for five months. Coincidence of 2.5 MV imaging beam with 6 MV therapy beam was verified with hidden-target cubic phantom. Image quality was studied using the Leeds and QC3 phantom. The depth of maximum dose, dmax, and percent dose at 10 cm depth were, respectively, 5.7 mm and 51.7% for CC13, 6.1 mm and 51.9% for Markus chamber, and 5.1 mm and 51.9% for EBT3 film. The 2.5 MV beam quality is slightly inferior to that of a 60Co teletherapy beam; however, an estimated kQ of 1.00 was used for output calibration purposes. The beam output was found to be stable to within 1% over a five-month period. The relative entrance dose as measured with EBT3 films was 63%, compared to 23% for a clinical 6 MV beam for a 10 × 10 cm2 field. Overall coincidence of the 2.5 MV imaging beam with the 6 MV clinical therapy beam was within 0.2 mm. Image quality results for two com-monly used imaging phantoms were superior for the 2.5 MV beam when compared to the conventional 6 MV beam. The results from measurements on two TrueBeam accelerators show that 2.5 MV imaging beam is slightly softer than a therapeutic 60Co beam, it provides superior image quality than a 6 MV therapy beam, and has excellent output stability. These 2.5 MV beam characterization results can serve as reference for clinics planning to commission and use this novel energy-image modality.


Assuntos
Aceleradores de Partículas/instrumentação , Imagens de Fantasmas , Intensificação de Imagem Radiográfica/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/normas , Tomografia Computadorizada por Raios X/métodos , Calibragem , Humanos , Dosagem Radioterapêutica
12.
J Nutr ; 145(9): 2006-11, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26224749

RESUMO

BACKGROUND: The biological effects of antioxidant nutrients are mediated in part by activation of antioxidant response elements (AREs) on genes for enzymes involved in endogenous pathways that prevent free radical damage. Traditional approaches for identifying antioxidant molecules in foods, such as total phenolic compound (TP) content or oxygen radical absorption capacity (ORAC), do not measure capacity to activate AREs. OBJECTIVES: The goal of this study was to develop an assay to assess the ARE activation capacity of fruit and vegetable extracts and determine whether such capacity was predicted by TP content and/or ORAC activity. METHODS: Fruits and vegetables were homogenized, extracted with acidified ethanol, lyophilized, and resuspended in growth medium. Human IMR-32 neuroblastoma cells, transfected with an ARE-firefly luciferase reporter, were exposed to extracts for 5 h. Firefly luciferase was normalized to constitutively expressed Renilla luciferase with tertiary butylhydroquinone (tBHQ) as a positive control. TP content and ORAC activity were measured for each extract. Relations between TPs and ORAC and ARE activity were determined. RESULTS: A total of 107 of 134 extracts tested significantly activated the ARE-luciferase reporter from 1.2- to 58-fold above that of the solvent control (P < 0.05) in human IMR-32 cells. ARE activity, TP content, and ORAC ranked higher in peels than in associated flesh. Despite this relation, ARE activity did not correlate with TP content (Spearman ρ = 0.05, P = 0.57) and only modestly but negatively correlated with ORAC (Spearman ρ = -0.24, P < 0.01). Many extracts activated the ARE more than predicted by the TP content or ORAC. CONCLUSIONS: The ARE reporter assay identified many active fruit and vegetable extracts in human IMR-32 cells. There are components of fruits and vegetables that activate the ARE but are not phenolic compounds and are low in ORAC. The ARE-luciferase reporter assay is likely a better predictor of the antioxidant benefits of fruits and vegetables than TP or ORAC.


Assuntos
Elementos de Resposta Antioxidante , Frutas/química , Extratos Vegetais/química , Verduras/química , Linhagem Celular Tumoral , Regulação da Expressão Gênica , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Humanos , Hidroquinonas/química , NAD(P)H Desidrogenase (Quinona)/genética , NAD(P)H Desidrogenase (Quinona)/metabolismo , Polifenóis/química , Espécies Reativas de Oxigênio/metabolismo
13.
Proc Natl Acad Sci U S A ; 109(26): 10462-7, 2012 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-22689992

RESUMO

An imbalance of commensal bacteria and their gene products underlies mucosal and, in particular, gastrointestinal inflammation and a predisposition to cancer. Lactobacillus species have received considerable attention as examples of beneficial microbiota. We have reported previously that deletion of the phosphoglycerol transferase gene that is responsible for lipoteichoic acid (LTA) biosynthesis in Lactobacillus acidophilus (NCK2025) rendered this bacterium able to significantly protect mice against induced colitis when delivered orally. Here we report that oral treatment with LTA-deficient NCK2025 normalizes innate and adaptive pathogenic immune responses and causes regression of established colonic polyps. This study reveals the proinflammatory role of LTA and the ability of LTA-deficient L. acidophilus to regulate inflammation and protect against colonic polyposis in a unique mouse model.


Assuntos
Polipose Adenomatosa do Colo/imunologia , Lactobacillus acidophilus/genética , Lipopolissacarídeos/genética , Ácidos Teicoicos/genética , Polipose Adenomatosa do Colo/patologia , Animais , Camundongos , Linfócitos T Reguladores/imunologia
14.
J Infect Dis ; 210(9): 1499-507, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24829464

RESUMO

Ingestion of Bacillus anthracis spores causes gastrointestinal (GI) anthrax. Humoral immune responses, particularly immunoglobulin A (IgA)-secreting B-1 cells, play a critical role in the clearance of GI pathogens. Here, we investigated whether B. anthracis impacts the function of colonic B-1 cells to establish active infection. GI anthrax led to significant inhibition of immunoglobulins (eg, IgA) and increased expression of program death 1 on B-1 cells. Furthermore, infection also diminished type 2 innate lymphoid cells (ILC2) and their ability to enhance differentiation and immunoglobulin production by secreting interleukin 5 (IL-5). Such B-1-cell and ILC2 dysfunction is potentially due to cleavage of p38 and Erk1/2 mitogen-activated protein kinases in these cells. Conversely, mice that survived infection generated neutralizing antibodies via the formation of robust germinal center B cells in Peyer's patches and had restored B-1-cell and ILC2 function. These data may provide additional insight for designing efficacious vaccines and therapeutics against this deadly pathogen.


Assuntos
Antraz/imunologia , Linfócitos B/fisiologia , Bacillus anthracis/fisiologia , Gastroenteropatias/imunologia , Animais , Bacillus anthracis/imunologia , Colo/imunologia , Colo/microbiologia , Citometria de Fluxo , Imunidade Celular/imunologia , Camundongos , Reação em Cadeia da Polimerase em Tempo Real
15.
Front Microbiol ; 15: 1341842, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38435695

RESUMO

As the climate changes, global systems have become increasingly unstable and unpredictable. This is particularly true for many disease systems, including subtypes of highly pathogenic avian influenzas (HPAIs) that are circulating the world. Ecological patterns once thought stable are changing, bringing new populations and organisms into contact with one another. Wild birds continue to be hosts and reservoirs for numerous zoonotic pathogens, and strains of HPAI and other pathogens have been introduced into new regions via migrating birds and transboundary trade of wild birds. With these expanding environmental changes, it is even more crucial that regions or counties that previously did not have surveillance programs develop the appropriate skills to sample wild birds and add to the understanding of pathogens in migratory and breeding birds through research. For example, little is known about wild bird infectious diseases and migration along the Mediterranean and Black Sea Flyway (MBSF), which connects Europe, Asia, and Africa. Focusing on avian influenza and the microbiome in migratory wild birds along the MBSF, this project seeks to understand the determinants of transboundary disease propagation and coinfection in regions that are connected by this flyway. Through the creation of a threat reduction network for avian diseases (Avian Zoonotic Disease Network, AZDN) in three countries along the MBSF (Georgia, Ukraine, and Jordan), this project is strengthening capacities for disease diagnostics; microbiomes; ecoimmunology; field biosafety; proper wildlife capture and handling; experimental design; statistical analysis; and vector sampling and biology. Here, we cover what is required to build a wild bird infectious disease research and surveillance program, which includes learning skills in proper bird capture and handling; biosafety and biosecurity; permits; next generation sequencing; leading-edge bioinformatics and statistical analyses; and vector and environmental sampling. Creating connected networks for avian influenzas and other pathogen surveillance will increase coordination and strengthen biosurveillance globally in wild birds.

16.
Behav Brain Res ; 465: 114932, 2024 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-38437921

RESUMO

Previous research investigated cross-modal influence of olfactory stimuli on perception and evaluation of faces. However, little is known about the neural dynamics underpinning this multisensory perception, and no research examined perception for images of oneself, and others, in presence of fragrances. This study investigated the neural mechanisms of olfactory-visual processing using electroencephalography (EEG) and subjective evaluations of self- and other-images. 22 female participants evaluated images of female actors and themselves while being exposed to the fragrance of a commercially available body wash or clean air delivered via olfactometer. Participants rated faces for attractiveness, femininity, confidence and glamorousness on visual analogue scales. EEG data was recorded and event-related potentials (ERPs) associated with onset of face stimuli were analysed to consider effects of fragrance presence on face processing, and interactions between fragrance and self-other image-type. Subjective ratings of confidence, attractiveness and femininity were increased for both image-types in pleasant fragrance relative to clean air condition. ERP components covering early-to-late stages of face processing were modulated by the presence of fragrance. Findings also revealed a cross-modal fragrance-face interaction, with pleasant fragrance particularly affecting ERPs to self-images in mid-latency ERP components. Results showed that the pleasant fragrance of the commercially available body wash impacted how participants perceived faces of self and others. Self- and other-image faces were subjectively rated as more attractive, confident and feminine in the presence of the pleasant fragrance compared to an un-fragranced control. The pleasant fragrance also modulated underlying electrophysiological activity. For the first time, an effect of pleasant fragrance on face perception was observed in the N1 component, suggesting impact within 100 ms. Pleasant fragrance also demonstrated greater impact on subsequent neural processing for self, relative to other-faces. The findings have implications for understanding multisensory integration during evaluations of oneself and others.


Assuntos
Feminilidade , Odorantes , Humanos , Feminino , Beleza , Potenciais Evocados/fisiologia , Eletroencefalografia
17.
Anticancer Drugs ; 24(10): 1098-103, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23995854
18.
Phys Rev E ; 107(4-1): 044402, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37198816

RESUMO

Cell migration is frequently modeled using on-lattice agent-based models (ABMs) that employ the excluded volume interaction. However, cells are also capable of exhibiting more complex cell-cell interactions, such as adhesion, repulsion, pulling, pushing, and swapping. Although the first four of these have already been incorporated into mathematical models for cell migration, swapping has not been well studied in this context. In this paper, we develop an ABM for cell movement in which an active agent can "swap" its position with another agent in its neighborhood with a given swapping probability. We consider a two-species system for which we derive the corresponding macroscopic model and compare it with the average behavior of the ABM. We see good agreement between the ABM and the macroscopic density. We also analyze the movement of agents at an individual level in the single-species as well as two-species scenarios to quantify the effects of swapping on an agent's motility.


Assuntos
Comunicação Celular , Modelos Teóricos , Probabilidade , Movimento Celular
19.
Bone Jt Open ; 4(5): 283-298, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37121581

RESUMO

To systematically review the efficacy of split tendon transfer surgery on gait-related outcomes for children and adolescents with cerebral palsy (CP) and spastic equinovarus foot deformity. Five databases (CENTRAL, CINAHL, PubMed, Embase, Web of Science) were systematically screened for studies investigating split tibialis anterior or split tibialis posterior tendon transfer for spastic equinovarus foot deformity, with gait-related outcomes (published pre-September 2022). Study quality and evidence were assessed using the Methodological Index for Non-Randomized Studies, the Risk of Bias In Non-Randomized Studies of Interventions, and the Grading of Recommendations Assessment, Development and Evaluation. Overall, 17 studies (566 feet) were included: 13 studies used clinical grading criteria to report a postoperative 'success' of 87% (75% to 100%), 14 reported on orthotic use with 88% reduced postoperative use, and one study reported on ankle kinematics improvements. Ten studies reported post-surgical complications at a rate of 11/390 feet (2.8%), but 84 feet (14.8%) had recurrent varus (68 feet, 12%) or occurrence of valgus (16 feet, 2.8%). Only one study included a patient-reported outcome measure (pain). Split tendon transfers are an effective treatment for children and youth with CP and spastic equinovarus foot deformities. Clinical data presented can be used for future study designs; a more standardized functional and patient-focused approach to evaluating outcomes of surgical intervention of gait may be warranted.

20.
Innate Immun ; 29(1-2): 14-24, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-37094088

RESUMO

The skin is the first line of defense to cutaneous microbes and viruses, and epidermal keratinocytes play a critical role in preventing infection by viruses and pathogens through activation of the type I interferon (IFN) response. Using RNAseq analysis, here we report that the conditional deletion of C/EBPß transcription factor in mouse epidermis (CKOß mice) resulted in the upregulation of IFNß and numerous keratinocyte interferon-stimulated genes (ISGs). The expression of cytosolic pattern recognition receptors (cPRRs), that recognize viral RNA and DNA, were significantly increased, and enriched in the RNAseq data set. cPRRs stimulate a type I IFN response that can trigger cell death to eliminate infected cells. To determine if the observed increases in cPRRs had functional consequences, we transfected CKOß primary keratinocytes with the pathogen and viral mimics poly(I:C) (dsRNA) or poly(dA:dT) (synthetic B-DNA) that directly activate PRRs. Transfected CKOß primary keratinocytes displayed an amplified type I IFN response which was accompanied by increased activation of IRF3, enhanced ISG expression, enhanced activation of caspase-8, caspase-3 and increased apoptosis. Our results identify C/EBPß as a critical repressor of the keratinocyte type I IFN response, and demonstrates that the loss of C/EBPß primes keratinocytes to the activation of cytosolic PRRs by pathogen RNA and DNA to induce cell death mediated by caspase-8 and caspase-3.


Assuntos
Proteína beta Intensificadora de Ligação a CCAAT , Interferon Tipo I , Animais , Camundongos , Caspase 3/metabolismo , Caspase 8/metabolismo , Proteína beta Intensificadora de Ligação a CCAAT/genética , Imunidade Inata , Interferon Tipo I/metabolismo , Queratinócitos , Receptores de Reconhecimento de Padrão/genética , Receptores de Reconhecimento de Padrão/metabolismo
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