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1.
J Sex Res ; : 1-10, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38832846

RESUMO

We conducted three studies to examine the factor structure and measurement invariance of the Paraphilia Scale, a measure of paraphilic interests used in multiple studies. In the first study, we conducted a confirmatory factor analysis (CFA) testing different a priori models with a community sample of 1,040 adults previously reported by Seto et al. (2021), and found support for a hierarchical four-factor model: An agonistic continuum involving coercion or physical pain (biastophilia, sexual sadism, masochism), chronophilias (pedophilia, hebephilia), courtship disorders (voyeurism, exhibitionism, and frotteurism), and fetishism (object fetishism, transvestic fetishism, urophilia-coprophilia). This factor structure was replicated in a second study comprising a combined sample of 400 mTurk participants and 870 university students. The third study analyzed the community sample and found evidence of configural invariance but not scalar or metric invariance across gender (man or woman) and sexual orientation for gender (heterosexual or other sexual orientation). This indicates that the factor structure of the Paraphilia Scale is robust for gender and sexual orientation for gender, but factor loadings differ across these groups, as do the loadings of individual items on the four factors. Implications for research on gender and sexual orientation differences in paraphilic interests are discussed.

2.
J Behav Ther Exp Psychiatry ; 80: 101795, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37247974

RESUMO

BACKGROUND AND OBJECTIVES: Negative post-event processing (PEP) is a key maintenance factor of social anxiety, but little is known about the role positive PEP, particularly in relation to situations that are not perceived as stressful. The objective was to examine negative and positive PEP following stressful and pleasant social interactions. We were also interested in how participants remembered and described the interactions. METHODS: Young adults (n = 411) recalled a recent pleasant or stressful social interaction and indicated how much negative and positive PEP they engaged in since the interaction. They also completed questionnaires measuring social anxiety and the memory's phenomenological qualities and wrote a description of the interaction. RESULTS: Higher social anxiety was linked with more negative and less positive PEP, regardless of whether the interaction was perceived as stressful or pleasant. Participants reporting more negative PEP used more negative words in describing the interaction and their memory was more negative and emotionally intense. Those reporting more positive PEP used more positive and less negative words in their descriptions. For stressful interactions, positive PEP was related to a more positive memory; for pleasant ones, it was related to increased emotional intensity. LIMITATIONS: Limitations included the sample type (restricted age range, non-clinical) and the retrospective, cross-sectional nature of the study. CONCLUSIONS: Results provide insight into PEP following stressful and pleasant social interactions. We also found preliminary evidence that positive PEP may be helpful and protective. Future studies may benefit from longitudinal and mixed methods designs.


Assuntos
Emoções , Interação Social , Adulto Jovem , Humanos , Estudos Retrospectivos , Estudos Transversais , Medo , Ansiedade/psicologia
3.
Behav Res Ther ; 159: 104208, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36252291

RESUMO

Socially anxious individuals tend to review past distressing social situations, a process called post-event processing. The goal of this 4-day study was to investigate how PEP evolved over time in between two speech tasks in a sample of 101 students using ecological momentary assessment (EMA). In addition, we examined the relationships between post-event processing and other cognitive and affective processes involved in social anxiety, including anticipatory processing, anxiety, performance appraisals, and memory. Results from EMA showed that post-event and anticipatory processing decreased over time. Higher anxiety during the speech and poorer performance appraisals predicted more post-event processing, though post-event processing was unrelated to changes in performance appraisals over time. Post-event processing the day following the first speech was positively associated with anticipatory processing the day before the second speech. Participants who engaged in more post-event processing also remembered the first speech differently (e.g., more negative and emotionally intense). Implications for the cognitive-behavioural treatment of social anxiety are discussed.


Assuntos
Avaliação Momentânea Ecológica , Fala , Humanos , Medo/psicologia , Ansiedade/psicologia , Cognição
4.
J Behav Ther Exp Psychiatry ; 74: 101694, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34543804

RESUMO

BACKGROUND AND OBJECTIVES: This study replicates and extends Houle-Johnson et al.'s (2019) findings to better understand the role of feedback modality, ambiguity and social anxiety in the recognition and recall of self-relevant feedback. METHODS: Participants gave a speech and were provided with positive, negative, and ambiguous feedback via written text, (n = 33) or recorded sentences (n = 31) and later completed a recognition and recall task for the feedback. RESULTS: Recognition (p = .80, ηp2 = 0) and recall (p = .09, ηp2 = 0.08) did not differ between written or recorded feedback. All participants demonstrated a negative response bias (p < .001, ηp2 = 0.22) and recalled more negative than positive feedback (p = .02, ηp2 = 0.10) but were no more accurate in recognizing negative compared to positive feedback (p = .08, ηp2 = 0). Although social anxiety did not impact recognition accuracy (p = .94, ηp2 = 0), participants with high social anxiety demonstrated a more pronounced negative response bias (p < .01, ηp2 = 0.11) and negative recall bias (p = .02, SE = 1.12) than low social anxiety participants. Moreover, the more negatively ambiguous items were perceived, the more likely they were identified old in the high social anxiety group, whereas the opposite was true for the low social anxiety group (B = .13, p < .10). LIMITATIONS: Task believability was relatively low across all participants. CONCLUSIONS: Our findings suggest that modality does not influence memory for feedback. Moreover, social anxiety might be characterized by a negative bias in recall and response bias, but not necessarily increased accuracy in recognition of negative feedback.


Assuntos
Rememoração Mental , Fala , Ansiedade , Retroalimentação , Humanos , Reconhecimento Psicológico
6.
Nat Commun ; 11(1): 4918, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33004800

RESUMO

In order to control and eradicate epidemic cholera, we need to understand how epidemics begin, how they spread, and how they decline and eventually end. This requires extensive sampling of epidemic disease over time, alongside the background of endemic disease that may exist concurrently with the epidemic. The unique circumstances surrounding the Argentinian cholera epidemic of 1992-1998 presented an opportunity to do this. Here, we use 490 Argentinian V. cholerae genome sequences to characterise the variation within, and between, epidemic and endemic V. cholerae. We show that, during the 1992-1998 cholera epidemic, the invariant epidemic clone co-existed alongside highly diverse members of the Vibrio cholerae species in Argentina, and we contrast the clonality of epidemic V. cholerae with the background diversity of local endemic bacteria. Our findings refine and add nuance to our genomic definitions of epidemic and endemic cholera, and are of direct relevance to controlling current and future cholera epidemics.


Assuntos
Cólera/microbiologia , Doenças Endêmicas/prevenção & controle , Genoma Bacteriano/genética , Pandemias/prevenção & controle , Vibrio cholerae/genética , Argentina/epidemiologia , Cólera/epidemiologia , Cólera/prevenção & controle , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , História do Século XIX , História do Século XX , Humanos , Anotação de Sequência Molecular , Pandemias/história , Filogenia , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Vibrio cholerae/isolamento & purificação , Vibrio cholerae/patogenicidade
7.
Nat Immunol ; 21(1): 86-100, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31844327

RESUMO

By developing a high-density murine immunophenotyping platform compatible with high-throughput genetic screening, we have established profound contributions of genetics and structure to immune variation (http://www.immunophenotype.org). Specifically, high-throughput phenotyping of 530 unique mouse gene knockouts identified 140 monogenic 'hits', of which most had no previous immunologic association. Furthermore, hits were collectively enriched in genes for which humans show poor tolerance to loss of function. The immunophenotyping platform also exposed dense correlation networks linking immune parameters with each other and with specific physiologic traits. Such linkages limit freedom of movement for individual immune parameters, thereby imposing genetically regulated 'immunologic structures', the integrity of which was associated with immunocompetence. Hence, we provide an expanded genetic resource and structural perspective for understanding and monitoring immune variation in health and disease.


Assuntos
Infecções por Enterobacteriaceae/imunologia , Variação Genética/genética , Ensaios de Triagem em Larga Escala/métodos , Imunofenotipagem/métodos , Infecções por Salmonella/imunologia , Animais , Citrobacter/imunologia , Infecções por Enterobacteriaceae/microbiologia , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Animais , Salmonella/imunologia , Infecções por Salmonella/microbiologia
8.
J Vis Exp ; (147)2019 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-31132035

RESUMO

The intestinal 'organoid' (iHO) system, wherein 3-D structures representative of the epithelial lining of the human gut can be produced from human induced pluripotent stem cells (hiPSCs) and maintained in culture, provides an exciting opportunity to facilitate the modeling of the epithelial response to enteric infections. In vivo, intestinal epithelial cells (IECs) play a key role in regulating intestinal homeostasis and may directly inhibit pathogens, although the mechanisms by which this occurs are not fully elucidated. The cytokine interleukin-22 (IL-22) has been shown to play a role in the maintenance and defense of the gut epithelial barrier, including inducing a release of antimicrobial peptides and chemokines in response to infection. We describe the differentiation of healthy control hiPSCs into iHOs via the addition of specific cytokine combinations to their culture medium before embedding them into a basement membrane matrix-based prointestinal culture system. Once embedded, the iHOs are grown in media supplemented with Noggin, R-spondin-1, epidermal growth factor (EGF), CHIR99021, prostaglandin E2, and Y-27632 dihydrochloride monohydrate. Weekly passages by manual disruption of the iHO ultrastructure lead to the formation of budded iHOs, with some exhibiting a crypt/villus structure. All iHOs demonstrate a differentiated epithelium consisting of goblet cells, enteroendocrine cells, Paneth cells, and polarized enterocytes, which can be confirmed via immunostaining for specific markers of each cell subset, transmission electron microscopy (TEM), and quantitative PCR (qPCR). To model infection, Salmonella enterica serovar Typhimurium SL1344 are microinjected into the lumen of the iHOs and incubated for 90 min at 37 °C, and a modified gentamicin protection assay is performed to identify the levels of intracellular bacterial invasion. Some iHOs are also pretreated with recombinant human IL-22 (rhIL-22) prior to infection to establish whether this cytokine is protective against Salmonella infection.


Assuntos
Células Epiteliais/microbiologia , Células-Tronco Pluripotentes Induzidas/citologia , Intestinos/citologia , Organoides/citologia , Salmonella/fisiologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Células Epiteliais/ultraestrutura , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/ultraestrutura , Interleucinas/farmacologia , Microinjeções , Interleucina 22
9.
Proc Biol Sci ; 286(1900): 20182025, 2019 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-30966987

RESUMO

The sixth global cholera pandemic lasted from 1899 to 1923. However, despite widespread fear of the disease and of its negative effects on troop morale, very few soldiers in the British Expeditionary Forces contracted cholera between 1914 and 1918. Here, we have revived and sequenced the genome of NCTC 30, a 102-year-old Vibrio cholerae isolate, which we believe is the oldest publicly available live V. cholerae strain in existence. NCTC 30 was isolated in 1916 from a British soldier convalescent in Egypt. We found that this strain does not encode cholera toxin, thought to be necessary to cause cholera, and is not part of V. cholerae lineages responsible for the pandemic disease. We also show that NCTC 30, which predates the introduction of penicillin-based antibiotics, harbours a functional ß-lactamase antibiotic resistance gene. Our data corroborate and provide molecular explanations for previous phenotypic studies of NCTC 30 and provide a new high-quality genome sequence for historical, non-pandemic V. cholerae.


Assuntos
Cólera/história , Genoma Bacteriano , Vibrio cholerae/genética , Cólera/microbiologia , História do Século XX , Análise de Sequência de DNA , I Guerra Mundial
10.
PLoS One ; 14(3): e0212481, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30840666

RESUMO

FBXO7 encodes an F box containing protein that interacts with multiple partners to facilitate numerous cellular processes and has a canonical role as part of an SCF E3 ubiquitin ligase complex. Mutation of FBXO7 is responsible for an early onset Parkinsonian pyramidal syndrome and genome-wide association studies have linked variants in FBXO7 to erythroid traits. A putative orthologue in Drosophila, nutcracker, has been shown to regulate the proteasome, and deficiency of nutcracker results in male infertility. Therefore, we reasoned that modulating Fbxo7 levels in a murine model could provide insights into the role of this protein in mammals. We used a targeted gene trap model which retained 4-16% residual gene expression and assessed the sensitivity of phenotypic traits to gene dosage. Fbxo7 hypomorphs showed regenerative anaemia associated with a shorter erythrocyte half-life, and male mice were infertile. Alterations to T cell phenotypes were also observed, which intriguingly were both T cell intrinsic and extrinsic. Hypomorphic mice were also sensitive to infection with Salmonella, succumbing to a normally sublethal challenge. Despite these phenotypes, Fbxo7 hypomorphs were produced at a normal Mendelian ratio with a normal lifespan and no evidence of neurological symptoms. These data suggest that erythrocyte survival, T cell development and spermatogenesis are particularly sensitive to Fbxo7 gene dosage.


Assuntos
Alelos , Proteínas F-Box , Dosagem de Genes , Regulação da Expressão Gênica , Infertilidade Masculina , Característica Quantitativa Herdável , Animais , Proteínas F-Box/biossíntese , Proteínas F-Box/genética , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Salmonella , Infecções por Salmonella/genética , Espermatogênese/genética
11.
PLoS One ; 13(5): e0197596, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29768502

RESUMO

Interferon lambda (IFNλ) is a group of cytokines that belong to the IL-10 family. They exhibit antiviral activities against certain viruses during infection of the liver and mucosal tissues. Here we report that IFNλ restricts in vitro replication of the ß-herpesvirus murine cytomegalovirus (mCMV). However, IFNλR1-deficient (Ifnλr1-/-) mice were not preferentially susceptible to mCMV infection in vivo during acute infection after systemic or mucosal challenge, or during virus persistence in the mucosa. Instead, our studies revealed that IFNλ influences NK cell responses during mCMV infection. Ifnλr1-/- mice exhibited defective development of conventional interferon-gamma (IFNγ)-expressing NK cells in the spleen during mCMV infection whereas accumulation of granzyme B-expressing NK cells was unaltered. In vitro, development of splenic IFNγ+ NK cells following stimulation with IL-12 or, to a lesser extent, IL-18 was abrogated by IFNλR1-deficiency. Thus, IFNλ regulates NK cell responses during mCMV infection and restricts virus replication in vitro but is redundant in the control of acute and persistent mCMV replication within mucosal and non-mucosal tissues.


Assuntos
Infecções por Herpesviridae/imunologia , Interferon gama/metabolismo , Interferons/metabolismo , Células Matadoras Naturais/imunologia , Muromegalovirus/imunologia , Animais , Feminino , Técnicas In Vitro , Células Matadoras Naturais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Muromegalovirus/fisiologia , Replicação Viral
12.
J Exp Med ; 214(4): 1111-1128, 2017 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-28351984

RESUMO

The phagocyte respiratory burst is crucial for innate immunity. The transfer of electrons to oxygen is mediated by a membrane-bound heterodimer, comprising gp91phox and p22phox subunits. Deficiency of either subunit leads to severe immunodeficiency. We describe Eros (essential for reactive oxygen species), a protein encoded by the previously undefined mouse gene bc017643, and show that it is essential for host defense via the phagocyte NAPDH oxidase. Eros is required for expression of the NADPH oxidase components, gp91phox and p22phox Consequently, Eros-deficient mice quickly succumb to infection. Eros also contributes to the formation of neutrophil extracellular traps (NETS) and impacts on the immune response to melanoma metastases. Eros is an ortholog of the plant protein Ycf4, which is necessary for expression of proteins of the photosynthetic photosystem 1 complex, itself also an NADPH oxio-reductase. We thus describe the key role of the previously uncharacterized protein Eros in host defense.


Assuntos
Proteínas de Membrana/fisiologia , Fagócitos/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Explosão Respiratória/fisiologia , Animais , Grupo dos Citocromos b/análise , Grupo dos Citocromos b/fisiologia , Retículo Endoplasmático/metabolismo , Células HEK293 , Humanos , Imunidade Inata , Macrófagos/imunologia , Glicoproteínas de Membrana/análise , Glicoproteínas de Membrana/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , NADPH Oxidase 2 , NADPH Oxidases/análise , NADPH Oxidases/fisiologia , Neutrófilos/imunologia , Fagocitose
13.
J Clin Invest ; 127(4): 1463-1474, 2017 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-28240600

RESUMO

The antiviral restriction factor IFN-induced transmembrane protein 3 (IFITM3) inhibits cell entry of a number of viruses, and genetic diversity within IFITM3 determines susceptibility to viral disease in humans. Here, we used the murine CMV (MCMV) model of infection to determine that IFITM3 limits herpesvirus-associated pathogenesis without directly preventing virus replication. Instead, IFITM3 promoted antiviral cellular immunity through the restriction of virus-induced lymphopenia, apoptosis-independent NK cell death, and loss of T cells. Viral disease in Ifitm3-/- mice was accompanied by elevated production of cytokines, most notably IL-6. IFITM3 inhibited IL-6 production by myeloid cells in response to replicating and nonreplicating virus as well as following stimulation with the TLR ligands Poly(I:C) and CpG. Although IL-6 promoted virus-specific T cell responses, uncontrolled IL-6 expression in Ifitm3-/- mice triggered the loss of NK cells and subsequently impaired control of MCMV replication. Thus, IFITM3 represents a checkpoint regulator of antiviral immunity that controls cytokine production to restrict viral pathogenesis. These data suggest the utility of cytokine-targeting strategies in the treatment of virus-infected individuals with impaired IFITM3 activity.


Assuntos
Citocinas/fisiologia , Infecções por Herpesviridae/metabolismo , Proteínas de Membrana/fisiologia , Animais , Células Cultivadas , Infecções por Herpesviridae/imunologia , Imunidade Celular , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Muromegalovirus/fisiologia , Receptores de Interleucina-6/metabolismo , Transdução de Sinais , Internalização do Vírus , Replicação Viral
14.
Exp Hematol ; 45: 64-68.e5, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27666489

RESUMO

Failure to maintain a normal in vivo erythrocyte half-life results in the development of hemolytic anemia. Half-life is affected by numerous factors, including energy balance, electrolyte gradients, reactive oxygen species, and membrane plasticity. The heterotrimeric AMP-activated protein kinase (AMPK) is an evolutionarily conserved serine/threonine kinase that acts as a critical regulator of cellular energy balance. Previous roles for the alpha 1 and gamma 1 subunits in the control of erythrocyte survival have been reported. In the work described here, we studied the role of the beta 1 subunit in erythrocytes and observed microcytic anemia with compensatory extramedullary hematopoiesis together with splenomegaly and increased osmotic resistance.


Assuntos
Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Eritrócitos/metabolismo , Anemia Hipocrômica/genética , Anemia Hipocrômica/metabolismo , Anemia Hipocrômica/patologia , Animais , Eritrócitos/citologia , Eritrócitos/patologia , Eritrócitos/ultraestrutura , Eritropoese/genética , Feminino , Expressão Gênica , Masculino , Camundongos , Camundongos Knockout , Isoformas de Proteínas , Baço/metabolismo , Baço/patologia
15.
Behav Brain Res ; 320: 374-382, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-27836584

RESUMO

Puberty is a critical period of development during which sexual maturity is attained. It is also a critical period for brain reorganization and it is vulnerable to exposure to certain environmental factors. Exposure to stress during this period can cause enduring neural and behavioral alterations. More specifically, exposure to an immune challenge during this period can alter reproductive as well as a number of non-reproductive behaviors and can permanently alter the brain's response to gonadal hormones. The present review examines the enduring effect of exposure to LPS and poly(I:C) during the pubertal period. Age and sex differences in acute response to LPS are discussed as possible mechanisms of vulnerability to adverse effects. Moreover, this review suggests new research directions to improve our understanding of the vulnerability of the pubertal period to immunological stressors.


Assuntos
Envelhecimento/fisiologia , Imunidade/fisiologia , Puberdade/fisiologia , Caracteres Sexuais , Envelhecimento/efeitos dos fármacos , Envelhecimento/patologia , Animais , Animais Recém-Nascidos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Modelos Animais de Doenças , Feminino , Hormônios Gonadais/metabolismo , Humanos , Comportamento de Doença/efeitos dos fármacos , Imunidade/efeitos dos fármacos , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Poli I-C/toxicidade , Ratos
16.
Nature ; 539(7627): 102-106, 2016 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-27749818

RESUMO

Innate lymphoid cells (ILCs) functionally resemble T lymphocytes in cytotoxicity and cytokine production but lack antigen-specific receptors, and they are important regulators of immune responses and tissue homeostasis. ILCs are generated from common lymphoid progenitors, which are subsequently committed to innate lymphoid lineages in the α-lymphoid progenitor, early innate lymphoid progenitor, common helper innate lymphoid progenitor and innate lymphoid cell progenitor compartments. ILCs consist of conventional natural killer cells and helper-like cells (ILC1, ILC2 and ILC3). Despite recent advances, the cellular heterogeneity, developmental trajectory and signalling dependence of ILC progenitors are not fully understood. Here, using single-cell RNA-sequencing (scRNA-seq) of mouse bone marrow progenitors, we reveal ILC precursor subsets, delineate distinct ILC development stages and pathways, and report that high expression of programmed death 1 (PD-1hi) marked a committed ILC progenitor that was essentially identical to an innate lymphoid cell progenitor. Our data defined PD-1hiIL-25Rhi as an early checkpoint in ILC2 development, which was abolished by deficiency in the zinc-finger protein Bcl11b but restored by IL-25R overexpression. Similar to T lymphocytes, PD-1 was upregulated on activated ILCs. Administration of a PD-1 antibody depleted PD-1hi ILCs and reduced cytokine levels in an influenza infection model in mice, and blocked papain-induced acute lung inflammation. These results provide a perspective for exploring PD-1 and its ligand (PD-L1) in immunotherapy, and allow effective manipulation of the immune system for disease prevention and therapy.


Assuntos
Sequência de Bases , Linhagem da Célula , Imunidade Inata , Linfócitos/citologia , Células Progenitoras Linfoides/citologia , Receptor de Morte Celular Programada 1/metabolismo , Análise de Célula Única , Animais , Anticorpos/imunologia , Diferenciação Celular , Linhagem da Célula/genética , Separação Celular , Citocinas/imunologia , Citocinas/metabolismo , Modelos Animais de Doenças , Humanos , Imunoterapia/tendências , Influenza Humana/imunologia , Influenza Humana/metabolismo , Células Matadoras Naturais/citologia , Ativação Linfocitária , Linfócitos/imunologia , Linfócitos/metabolismo , Células Progenitoras Linfoides/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Pneumonia/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/imunologia , Receptores de Interleucina/metabolismo , Proteínas Repressoras/deficiência , Proteínas Repressoras/metabolismo , Linfócitos T/metabolismo , Proteínas Supressoras de Tumor/deficiência , Proteínas Supressoras de Tumor/metabolismo
17.
Nat Microbiol ; 1: 15023, 2016 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-27572160

RESUMO

Host adaptation is a key factor contributing to the emergence of new bacterial, viral and parasitic pathogens. Many pathogens are considered promiscuous because they cause disease across a range of host species, while others are host-adapted, infecting particular hosts(1). Host adaptation can potentially progress to host restriction, where the pathogen is strictly limited to a single host species and is frequently associated with more severe symptoms. Host-adapted and host-restricted bacterial clades evolve from within a broader host-promiscuous species and sometimes target different niches within their specialist hosts, such as adapting from a mucosal to a systemic lifestyle. Genome degradation, marked by gene inactivation and deletion, is a key feature of host adaptation, although the triggers initiating genome degradation are not well understood. Here, we show that a chronic systemic non-typhoidal Salmonella infection in an immunocompromised human patient resulted in genome degradation targeting genes that are expendable for a systemic lifestyle. We present a genome-based investigation of a recurrent blood-borne Salmonella enterica serotype Enteritidis (S. Enteritidis) infection covering 15 years in an interleukin-12 ß1 receptor-deficient individual that developed into an asymptomatic chronic infection. The infecting S. Enteritidis harboured a mutation in the mismatch repair gene mutS that accelerated the genomic mutation rate. Phylogenetic analysis and phenotyping of multiple patient isolates provides evidence for a remarkable level of within-host evolution that parallels genome changes present in successful host-restricted bacterial pathogens but never before observed on this timescale. Our analysis identifies common pathways of host adaptation and demonstrates the role that immunocompromised individuals can play in this process.


Assuntos
Adaptação Biológica , Bacteriemia/microbiologia , Interações Hospedeiro-Patógeno , Hospedeiro Imunocomprometido , Infecções por Salmonella/microbiologia , Salmonella enteritidis/genética , Salmonella enteritidis/isolamento & purificação , Evolução Molecular , Deleção de Genes , Variação Genética , Genoma Bacteriano , Humanos , Proteína MutS de Ligação de DNA com Erro de Pareamento/deficiência , Taxa de Mutação , Filogenia , Salmonella enteritidis/classificação , Fatores de Tempo
18.
mBio ; 7(3)2016 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-27329747

RESUMO

UNLABELLED: Mice harboring a mutation in the gene encoding gastric intrinsic factor (Gif), a protein essential for the absorption of vitamin B12/cobalamin (Cbl), have potential as a model to explore the role of vitamins in infection. The levels of Cbl in the blood of Gif(tm1a/tm1a) mutant mice were influenced by the maternal genotype, with offspring born to heterozygous (high Cbl, F1) mothers exhibiting a significantly higher serum Cbl level than those born to homozygous (low Cbl, F2) equivalents. Low Cbl levels correlated with susceptibility to an infectious challenge with Salmonella enterica serovar Typhimurium or Citrobacter rodentium, and this susceptibility phenotype was moderated by Cbl administration. Transcriptional and metabolic profiling revealed that Cbl deficient mice exhibited a bioenergetic shift similar to a metabolic phenomenon commonly found in cancerous cells under hypoxic conditions known as the Warburg effect, with this metabolic effect being exacerbated further by infection. Our findings demonstrate a role for Cbl in bacterial infection, with potential general relevance to dietary deficiency and infection susceptibility. IMPORTANCE: Malnutrition continues to be a major public health problem in countries with weak infrastructures. In communities with a high prevalence of poor diet, malnourishment and infectious disease can impact vulnerable individuals such as pregnant women and children. Here, we describe a highly flexible murine model for monitoring maternal and environmental influences of vitamin B12 metabolism. We also demonstrate the potential importance of vitamin B12 in controlling susceptibility to bacterial pathogens such as C. rodentium and S Typhimurium. We postulate that this model, along with similarly vitamin deficient mice, could be used to further explore the mechanisms associated with micronutrients and susceptibility to diseases, thereby increasing our understanding of disease in the malnourished.


Assuntos
Suscetibilidade a Doenças , Infecções por Enterobacteriaceae/imunologia , Deficiência de Vitamina B 12/complicações , Animais , Citrobacter rodentium/imunologia , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Metaboloma , Camundongos , Camundongos Knockout , Salmonella typhimurium/imunologia
19.
J Exp Med ; 213(6): 1061-77, 2016 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-27217537

RESUMO

Enteric fever, caused by Salmonella enterica serovar Typhi, is an important public health problem in resource-limited settings and, despite decades of research, human responses to the infection are poorly understood. In 41 healthy adults experimentally infected with wild-type S. Typhi, we detected significant cytokine responses within 12 h of bacterial ingestion. These early responses did not correlate with subsequent clinical disease outcomes and likely indicate initial host-pathogen interactions in the gut mucosa. In participants developing enteric fever after oral infection, marked transcriptional and cytokine responses during acute disease reflected dominant type I/II interferon signatures, which were significantly associated with bacteremia. Using a murine and macrophage infection model, we validated the pivotal role of this response in the expression of proteins of the host tryptophan metabolism during Salmonella infection. Corresponding alterations in tryptophan catabolites with immunomodulatory properties in serum of participants with typhoid fever confirmed the activity of this pathway, and implicate a central role of host tryptophan metabolism in the pathogenesis of typhoid fever.


Assuntos
Imunomodulação , Interferon Tipo I/imunologia , Interferon gama/imunologia , Salmonella typhi/imunologia , Triptofano/imunologia , Febre Tifoide/imunologia , Adulto , Feminino , Humanos , Interferon Tipo I/sangue , Interferon gama/sangue , Masculino , Pessoa de Meia-Idade , Salmonella typhi/metabolismo , Triptofano/biossíntese , Febre Tifoide/sangue , Febre Tifoide/patologia
20.
Nat Microbiol ; 1(3)2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-27127642

RESUMO

Host adaptation is a key factor contributing to the emergence of new bacterial, viral and parasitic pathogens. Many pathogens are considered promiscuous because they cause disease across a range of host species, while others are host-adapted, infecting particular hosts1. Host adaptation can potentially progress to host restriction where the pathogen is strictly limited to a single host species and is frequently associated with more severe symptoms. Host-adapted and host-restricted bacterial clades evolve from within a broader host-promiscuous species and sometimes target different niches within their specialist hosts, such as adapting from a mucosal to a systemic lifestyle. Genome degradation, marked by gene inactivation and deletion, is a key feature of host adaptation, although the triggers initiating genome degradation are not well understood. Here, we show that a chronic systemic non-typhoidal Salmonella infection in an immunocompromised human patient resulted in genome degradation targeting genes that are expendable for a systemic lifestyle. We present a genome-based investigation of a recurrent blood-borne Salmonella enterica serotype Enteritidis (S. Enteritidis) infection covering 15 years in an interleukin (IL)-12 ß-1 receptor-deficient individual that developed into an asymptomatic chronic infection. The infecting S. Enteritidis harbored a mutation in the mismatch repair gene mutS that accelerated the genomic mutation rate. Phylogenetic analysis and phenotyping of multiple patient isolates provides evidence for a remarkable level of within-host evolution that parallels genome changes present in successful host-restricted bacterial pathogens but never before observed on this timescale. Our analysis identifies common pathways of host adaptation and demonstrates the role that immunocompromised individuals can play in this process.


Assuntos
Adaptação Fisiológica/genética , Genoma Bacteriano , Interações Hospedeiro-Patógeno , Hospedeiro Imunocomprometido , Síndromes de Imunodeficiência/complicações , Infecções por Salmonella/microbiologia , Salmonella enteritidis/genética , Adulto , Bacteriemia/microbiologia , Doença Crônica , Evolução Molecular , Especificidade de Hospedeiro , Humanos , Subunidade beta 1 de Receptor de Interleucina-12/deficiência , Subunidade beta 1 de Receptor de Interleucina-12/genética , Mutação , Taxa de Mutação , Infecções por Salmonella/complicações , Salmonella enteritidis/classificação , Salmonella enteritidis/isolamento & purificação , Salmonella enteritidis/patogenicidade , Virulência
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