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1.
Philos Trans R Soc Lond B Biol Sci ; 379(1895): 20220420, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38104601

RESUMO

Expectation is crucial for our enjoyment of music, yet the underlying generative mechanisms remain unclear. While sensory models derive predictions based on local acoustic information in the auditory signal, cognitive models assume abstract knowledge of music structure acquired over the long term. To evaluate these two contrasting mechanisms, we compared simulations from four computational models of musical expectancy against subjective expectancy and pleasantness ratings of over 1000 chords sampled from 739 US Billboard pop songs. Bayesian model comparison revealed that listeners' expectancy and pleasantness ratings were predicted by the independent, non-overlapping, contributions of cognitive and sensory expectations. Furthermore, cognitive expectations explained over twice the variance in listeners' perceived surprise compared to sensory expectations, suggesting a larger relative importance of long-term representations of music structure over short-term sensory-acoustic information in musical expectancy. Our results thus emphasize the distinct, albeit complementary, roles of cognitive and sensory expectations in shaping musical pleasure, and suggest that this expectancy-driven mechanism depends on musical information represented at different levels of abstraction along the neural hierarchy. This article is part of the theme issue 'Art, aesthetics and predictive processing: theoretical and empirical perspectives'.


Assuntos
Música , Prazer , Percepção Auditiva , Música/psicologia , Motivação , Teorema de Bayes , Cognição , Estimulação Acústica/métodos
2.
Neuroimage ; 275: 120116, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37169118

RESUMO

Electroencephalographic (EEG) methods have great potential to serve both basic and clinical science approaches to understand individual differences in human neural function. Importantly, the psychometric properties of EEG data, such as internal consistency and test-retest reliability, constrain their ability to differentiate individuals successfully. Rapid and recent technological and computational advancements in EEG research make it timely to revisit the topic of psychometric reliability in the context of individual difference analyses. Moreover, pediatric and clinical samples provide some of the most salient and urgent opportunities to apply individual difference approaches, but the changes these populations experience over time also provide unique challenges from a psychometric perspective. Here we take a developmental neuroscience perspective to consider progress and new opportunities for parsing the reliability and stability of individual differences in EEG measurements across the lifespan. We first conceptually map the different profiles of measurement reliability expected for different types of individual difference analyses over the lifespan. Next, we summarize and evaluate the state of the field's empirical knowledge and need for testing measurement reliability, both internal consistency and test-retest reliability, across EEG measures of power, event-related potentials, nonlinearity, and functional connectivity across ages. Finally, we highlight how standardized pre-processing software for EEG denoising and empirical metrics of individual data quality may be used to further improve EEG-based individual differences research moving forward. We also include recommendations and resources throughout that individual researchers can implement to improve the utility and reproducibility of individual differences analyses with EEG across the lifespan.


Assuntos
Individualidade , Longevidade , Humanos , Criança , Reprodutibilidade dos Testes , Eletroencefalografia/métodos , Potenciais Evocados
3.
Brain Struct Funct ; 228(1): 273-291, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35476027

RESUMO

Semantic knowledge is central to human cognition. The angular gyrus (AG) is widely considered a key brain region for semantic cognition. However, the role of the AG in semantic processing is controversial. Key controversies concern response polarity (activation vs. deactivation) and its relation to task difficulty, lateralization (left vs. right AG), and functional-anatomical subdivision (PGa vs. PGp subregions). Here, we combined the fMRI data of five studies on semantic processing (n = 172) and analyzed the response profiles from the same anatomical regions-of-interest for left and right PGa and PGp. We found that the AG was consistently deactivated during non-semantic conditions, whereas response polarity during semantic conditions was inconsistent. However, the AG consistently showed relative response differences between semantic and non-semantic conditions, and between different semantic conditions. A combined analysis across all studies revealed that AG responses could be best explained by separable effects of task difficulty and semantic processing demand. Task difficulty effects were stronger in PGa than PGp, regardless of hemisphere. Semantic effects were stronger in left than right AG, regardless of subregion. These results suggest that the AG is engaged in both domain-general task-difficulty-related processes and domain-specific semantic processes. In semantic processing, we propose that left AG acts as a "multimodal convergence zone" that binds different semantic features associated with the same concept, enabling efficient access to task-relevant features.


Assuntos
Mapeamento Encefálico , Lobo Parietal , Humanos , Mapeamento Encefálico/métodos , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/fisiologia , Cognição/fisiologia , Semântica , Neuroimagem Funcional , Imageamento por Ressonância Magnética/métodos
5.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-463665

RESUMO

Extrapulmonary complications of different organ systems have been increasingly recognized in patients with severe or chronic Coronavirus Disease 2019 (COVID-19). However, limited information on the skeletal complications of COVID-19 is known, even though inflammatory diseases of the respiratory tract have been known to perturb bone metabolism and cause pathological bone loss. In this study, we characterized the effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection on bone metabolism in an established golden Syrian hamster model for COVID-19. SARS-CoV-2 causes significant multifocal loss of bone trabeculae in the long bones and lumbar vertebrae of all infected hamsters. The bone loss progressively worsens from the acute phase to the post-recovery phase. Mechanistically, the bone loss was associated with SARS-CoV-2-induced cytokine dysregulation which upregulates osteoclastic differentiation of monocyte-macrophage lineage. The pro-inflammatory cytokines further trigger a second wave of cytokine storm in the skeletal tissues to augment their pro-osteoclastogenesis effect. Our findings in this established hamster model suggest that pathological bone loss may be a neglected complication which warrants more extensive investigations during the long-term follow-up of COVID-19 patients. The benefits of potential prophylactic and therapeutic interventions against pathological bone loss should be further evaluated. O_FIG O_LINKSMALLFIG WIDTH=188 HEIGHT=200 SRC="FIGDIR/small/463665v1_ufig1.gif" ALT="Figure 1"> View larger version (81K): org.highwire.dtl.DTLVardef@ada9b8org.highwire.dtl.DTLVardef@1617fcaorg.highwire.dtl.DTLVardef@cdcd3org.highwire.dtl.DTLVardef@75a0ab_HPS_FORMAT_FIGEXP M_FIG C_FIG Graphical abstractSARS-CoV-2 infection causes pathological bone loss in golden Syrian hamsters through induction of cytokine storm and inflammation-induced osteoclastogenesis.

6.
Sci Rep ; 11(1): 10119, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33980876

RESUMO

Neurobiological models of emotion focus traditionally on limbic/paralimbic regions as neural substrates of emotion generation, and insular cortex (in conjunction with isocortical anterior cingulate cortex, ACC) as the neural substrate of feelings. An emerging view, however, highlights the importance of isocortical regions beyond insula and ACC for the subjective feeling of emotions. We used music to evoke feelings of joy and fear, and multivariate pattern analysis (MVPA) to decode representations of feeling states in functional magnetic resonance (fMRI) data of n = 24 participants. Most of the brain regions providing information about feeling representations were neocortical regions. These included, in addition to granular insula and cingulate cortex, primary and secondary somatosensory cortex, premotor cortex, frontal operculum, and auditory cortex. The multivoxel activity patterns corresponding to feeling representations emerged within a few seconds, gained in strength with increasing stimulus duration, and replicated results of a hypothesis-generating decoding analysis from an independent experiment. Our results indicate that several neocortical regions (including insula, cingulate, somatosensory and premotor cortices) are important for the generation and modulation of feeling states. We propose that secondary somatosensory cortex, which covers the parietal operculum and encroaches on the posterior insula, is of particular importance for the encoding of emotion percepts, i.e., preverbal representations of subjective feeling.


Assuntos
Emoções/fisiologia , Potenciais Evocados Auditivos , Giro do Cíngulo/fisiologia , Música , Neocórtex/fisiologia , Córtex Somatossensorial/fisiologia , Estimulação Acústica , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
7.
Neuroimage ; 219: 117041, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32534127

RESUMO

Conceptual knowledge is central to human cognition. The left posterior inferior parietal lobe (pIPL) is implicated by neuroimaging studies as a multimodal hub representing conceptual knowledge related to various perceptual-motor modalities. However, the causal role of left pIPL in conceptual processing remains unclear. Here, we transiently disrupted left pIPL function with transcranial magnetic stimulation (TMS) to probe its causal relevance for the retrieval of action and sound knowledge. We compared effective TMS over left pIPL with sham TMS, while healthy participants performed three different tasks-lexical decision, action judgment, and sound judgment-on words with a high or low association to actions and sounds. We found that pIPL-TMS selectively impaired action judgments on low sound-low action words. For the first time, we directly related computational simulations of the TMS-induced electrical field to behavioral performance, which revealed that stronger stimulation of left pIPL is associated with worse performance for action but not sound judgments. These results indicate that left pIPL causally supports conceptual processing when action knowledge is task-relevant and cannot be compensated by sound knowledge. Our findings suggest that left pIPL is specialized for the retrieval of action knowledge, challenging the view of left pIPL as a multimodal conceptual hub.


Assuntos
Cognição/fisiologia , Julgamento/fisiologia , Rememoração Mental/fisiologia , Lobo Parietal/fisiologia , Adulto , Mapeamento Encefálico , Simulação por Computador , Feminino , Humanos , Conhecimento , Idioma , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Lobo Parietal/diagnóstico por imagem , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Estimulação Magnética Transcraniana , Adulto Jovem
8.
ACS Infect Dis ; 6(7): 1745-1758, 2020 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-32329611

RESUMO

Zika virus (ZIKV) is an emerging flavivirus that may be associated with congenital anomalies in infected fetuses and severe neurological and genital tract complications in infected adults. Currently, antiviral treatments to revert these ZIKV-induced complications are lacking. ZIKV infection has recently been suggested to upregulate the host unfolded protein response, which may contribute to the congenital neurological anomalies. As an extension from these findings, we thoroughly investigated the ZIKV-induced unfolded protein response using a combination of the neuronal cell line, induced pluripotent stem cell-derived human neuronal stem and progenitor cells, and an interferon receptor-deficient A129 mouse model. Our results revealed a critical contribution of the inositol-requiring enzyme-1 (IRE1) arm of the unfolded protein response to ZIKV-induced neurological and testicular complications. Importantly, the inhibition of the IRE1 signaling pathway activation with KIRA6 (kinase-inhibiting RNAse attenuator 6), a selective small molecule IRE1 inhibitor that promotes cell survival, potently reverted the ZIKV-induced perturbations of the key gene expressions associated with neurogenesis and spermatogenesis in vitro and in vivo, highlighting the potential of IRE1 inhibition as a novel host-targeting antiviral strategy in combating against ZIKV-induced neurological and testicular pathologies.


Assuntos
Infecção por Zika virus , Zika virus , Humanos , Imidazóis , Inositol , Naftalenos , Neurogênese , Proteínas Serina-Treonina Quinases , Pirazinas , Espermatogênese , Infecção por Zika virus/tratamento farmacológico
9.
Curr Biol ; 29(23): 4084-4092.e4, 2019 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-31708393

RESUMO

Listening to music often evokes intense emotions [1, 2]. Recent research suggests that musical pleasure comes from positive reward prediction errors, which arise when what is heard proves to be better than expected [3]. Central to this view is the engagement of the nucleus accumbens-a brain region that processes reward expectations-to pleasurable music and surprising musical events [4-8]. However, expectancy violations along multiple musical dimensions (e.g., harmony and melody) have failed to implicate the nucleus accumbens [9-11], and it is unknown how music reward value is assigned [12]. Whether changes in musical expectancy elicit pleasure has thus remained elusive [11]. Here, we demonstrate that pleasure varies nonlinearly as a function of the listener's uncertainty when anticipating a musical event, and the surprise it evokes when it deviates from expectations. Taking Western tonal harmony as a model of musical syntax, we used a machine-learning model [13] to mathematically quantify the uncertainty and surprise of 80,000 chords in US Billboard pop songs. Behaviorally, we found that chords elicited high pleasure ratings when they deviated substantially from what the listener had expected (low uncertainty, high surprise) or, conversely, when they conformed to expectations in an uninformative context (high uncertainty, low surprise). Neurally, we found using fMRI that activity in the amygdala, hippocampus, and auditory cortex reflected this interaction, while the nucleus accumbens only reflected uncertainty. These findings challenge current neurocognitive models of music-evoked pleasure and highlight the synergistic interplay between prospective and retrospective states of expectation in the musical experience. VIDEO ABSTRACT.


Assuntos
Percepção Auditiva/fisiologia , Música , Prazer , Incerteza , Adulto , Tonsila do Cerebelo/fisiologia , Córtex Auditivo/fisiologia , Feminino , Hipocampo/fisiologia , Humanos , Masculino , Núcleo Accumbens/fisiologia , Adulto Jovem
10.
Sci Rep ; 8(1): 3822, 2018 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-29491454

RESUMO

Complex auditory sequences known as music have often been described as hierarchically structured. This permits the existence of non-local dependencies, which relate elements of a sequence beyond their temporal sequential order. Previous studies in music have reported differential activity in the inferior frontal gyrus (IFG) when comparing regular and irregular chord-transitions based on theories in Western tonal harmony. However, it is unclear if the observed activity reflects the interpretation of hierarchical structure as the effects are confounded by local irregularity. Using functional magnetic resonance imaging (fMRI), we found that violations to non-local dependencies in nested sequences of three-tone musical motifs in musicians elicited increased activity in the right IFG. This is in contrast to similar studies in language which typically report the left IFG in processing grammatical syntax. Effects of increasing auditory working demands are moreover reflected by distributed activity in frontal and parietal regions. Our study therefore demonstrates the role of the right IFG in processing non-local dependencies in music, and suggests that hierarchical processing in different cognitive domains relies on similar mechanisms that are subserved by domain-selective neuronal subpopulations.


Assuntos
Música , Córtex Pré-Frontal/fisiologia , Adolescente , Percepção Auditiva , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Memória de Curto Prazo , Córtex Pré-Frontal/diagnóstico por imagem
11.
Nat Microbiol ; 1: 16004, 2016 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-27572168

RESUMO

Middle East respiratory syndrome coronavirus (MERS-CoV) causes sporadic zoonotic disease and healthcare-associated outbreaks in human. MERS is often complicated by acute respiratory distress syndrome (ARDS) and multi-organ failure(1,2). The high incidence of renal failure in MERS is a unique clinical feature not often found in other human coronavirus infections(3,4). Whether MERS-CoV infects the kidney and how it triggers renal failure are not understood(5,6). Here, we demonstrated renal infection and apoptotic induction by MERS-CoV in human ex vivo organ culture and a nonhuman primate model. High-throughput analysis revealed that the cellular genes most significantly perturbed by MERS-CoV have previously been implicated in renal diseases. Furthermore, MERS-CoV induced apoptosis through upregulation of Smad7 and fibroblast growth factor 2 (FGF2) expression in both kidney and lung cells. Conversely, knockdown of Smad7 effectively inhibited MERS-CoV replication and protected cells from virus-induced cytopathic effects. We further demonstrated that hyperexpression of Smad7 or FGF2 induced a strong apoptotic response in kidney cells. Common marmosets infected by MERS-CoV developed ARDS and disseminated infection in kidneys and other organs. Smad7 and FGF2 expression were elevated in the lungs and kidneys of the infected animals. Our results provide insights into the pathogenesis of MERS-CoV and host targets for treatment.


Assuntos
Apoptose , Infecções por Coronavirus/patologia , Fator 2 de Crescimento de Fibroblastos/metabolismo , Rim/patologia , Pulmão/patologia , Coronavírus da Síndrome Respiratória do Oriente Médio/patogenicidade , Proteína Smad7/metabolismo , Animais , Callithrix , Efeito Citopatogênico Viral , Modelos Animais de Doenças , Interações Hospedeiro-Patógeno , Humanos , Técnicas de Cultura de Órgãos
12.
J Virol ; 87(17): 9939-42, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23824801

RESUMO

A novel human Middle East respiratory syndrome coronavirus (MERS-CoV) caused outbreaks of severe acute respiratory syndrome (SARS)-like illness with a high mortality rate, raising concerns of its pandemic potential. Dipeptidyl peptidase-4 (DPP4) was recently identified as its receptor. Here we showed that residues 377 to 662 in the S protein of MERS-CoV specifically bound to DPP4-expressing cells and soluble DPP4 protein and induced significant neutralizing antibody responses, suggesting that this region contains the receptor-binding domain (RBD), which has a potential to be developed as a MERS-CoV vaccine.


Assuntos
Coronavirus/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Sítios de Ligação , Linhagem Celular , Coronavirus/genética , Coronavirus/imunologia , Infecções por Coronavirus/virologia , Dipeptidil Peptidase 4/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Terciária de Proteína , Receptores Virais/metabolismo , Infecções Respiratórias/virologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Virais/genética , Vacinas Virais/imunologia
13.
J Infect Dis ; 207(8): 1270-80, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23325916

RESUMO

BACKGROUND: Obesity is associated with a high circulating leptin level and severe 2009 pandemic influenza A virus subtype H1N1 (A[H1N1]pdm09) infection. The mechanism for severe lung injury in obese patients and the specific treatment strategy remain elusive. METHOD: We studied the pathogenesis of A(H1N1)pdm09 infection in a mouse model of diet-induced obesity. RESULTS: Obese mice had significantly higher initial pulmonary viral titer and mortality after challenge with A(H1N1)pdm09, compared with age-matched lean mice. Compared with lean mice, obese mice had heightened proinflammatory cytokine and chemokine levels and more severe pulmonary inflammatory damage. Furthermore, obese mice had a higher preexisting serum leptin level but a lower preexisting adiponectin level. Recombinant mouse leptin increased the interleukin 6 (IL-6) messenger RNA expression in mouse single-lung-cell preparations, mouse macrophages, and mouse lung epithelial cell lines infected with A(H1N1)pdm09. Administration of anti-leptin antibody improved the survival of infected obese mice, with associated reductions in pulmonary levels of the proinflammatory cytokines IL-6 and interleukin 1ß but not the pulmonary viral titer. CONCLUSIONS: Our findings suggest that preexisting high levels of circulating leptin contribute to the development of severe lung injury by A(H1N1)pdm09 in mice with diet-induced obesity. The therapeutic strategy of leptin neutralization for the reduction of proinflammatory responses and pulmonary damage in obese patients warrants further investigations.


Assuntos
Vírus da Influenza A Subtipo H1N1/patogenicidade , Interleucina-6/imunologia , Leptina/imunologia , Obesidade/imunologia , Infecções por Orthomyxoviridae/patologia , Animais , Anticorpos/administração & dosagem , Anticorpos/imunologia , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Epitélio/imunologia , Epitélio/patologia , Feminino , Interleucina-1beta/imunologia , Interleucina-6/genética , Estimativa de Kaplan-Meier , Leptina/metabolismo , Leptina/farmacologia , Pulmão/imunologia , Pulmão/patologia , Pulmão/virologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/virologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/virologia , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Pandemias , Pneumonia/imunologia , Pneumonia/patologia , Pneumonia/virologia , RNA Mensageiro/análise , RNA Mensageiro/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/farmacologia , Carga Viral
14.
J Infect Dis ; 206(4): 495-503, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22693232

RESUMO

Infection due to 2009 pandemic H1N1 influenza A virus (A[H1N1]pdm09) is commonly manifested as mild infection but occasionally as severe pneumonia. We hypothesized that host genetic variations may contribute to disease severity. An initially small-scale genome-wide association study guided the selection of CD55 single-nucleotide polymorphisms in 425 Chinese patients with severe (n = 177) or mild (n = 248) disease. Carriers of rs2564978 genotype T/T were significantly associated with severe infection (odds ratio, 1.75; P = .011) under a recessive model, after adjustment for clinical confounders. An allele-specific effect on CD55 expression was revealed and ascribed to a promoter indel variation, which was in complete linkage disequilibrium with rs2564978. The promoter variant with deletion exhibited significantly lower transcriptional activity. We further demonstrated that CD55 can protect respiratory epithelial cells from complement attack. Additionally, A(H1N1)pdm09 infection promoted CD55 expression. In conclusion, CD55 polymorphisms are associated with severe A(H1N1)pdm09 infection. CD55 may exert a substantial impact on the disease severity of A(H1N1)pdm09 infection.


Assuntos
Antígenos CD55/genética , Predisposição Genética para Doença , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H1N1/patogenicidade , Influenza Humana/genética , Influenza Humana/patologia , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD55/imunologia , China , Feminino , Frequência do Gene , Humanos , Mutação INDEL , Influenza Humana/imunologia , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas , Índice de Gravidade de Doença , Adulto Jovem
15.
Cell Mol Immunol ; 8(6): 462-8, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21946434

RESUMO

Interleukin-17 (IL-17), a member of the IL-17 cytokine family, plays a crucial role in mediating the immune response against extracellular bacteria and fungi in the lung. Although there is increasing evidence that IL-17 is involved in protective immunity against H1 and H3 influenza virus infections, little is known about the role of IL-17 in the highly pathogenic H5N1 influenza virus infection. In this study, we show that H5N1-infected IL-17 knockout (KO) mice exhibit markedly increased weight loss, more pronounced lung immunopathology and significantly reduced survival rates as compared with infected wild-type controls. Moreover, the frequency of B cells in the lung were substantially decreased in IL-17 KO mice after virus infection, which correlated with reduced CXCR5 expression in B cells and decreased CXCL13 production in the lung tissue of IL-17 KO mice. Consistent with this observation, B cells from IL-17 KO mice exhibited a significant reduction in chemokine-mediated migration in culture. Taken together, these findings demonstrate a critical role for IL-17 in mediating the recruitment of B cells to the site of pulmonary influenza virus infection in mice.


Assuntos
Linfócitos B/imunologia , Deleção de Genes , Virus da Influenza A Subtipo H5N1/imunologia , Interleucina-17/imunologia , Pulmão/virologia , Infecções por Orthomyxoviridae/imunologia , Animais , Linfócitos B/citologia , Linfócitos B/metabolismo , Movimento Celular/imunologia , Quimiocina CXCL13/biossíntese , Quimiocina CXCL13/imunologia , Regulação para Baixo , Feminino , Citometria de Fluxo , Humanos , Virus da Influenza A Subtipo H5N1/patogenicidade , Influenza Humana/imunologia , Influenza Humana/patologia , Influenza Humana/virologia , Interleucina-17/deficiência , Interleucina-17/genética , Pulmão/imunologia , Pulmão/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infecções por Orthomyxoviridae/mortalidade , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/virologia , Receptores CXCR5/biossíntese , Receptores CXCR5/imunologia , Taxa de Sobrevida , Redução de Peso
16.
Eur J Pharmacol ; 660(2-3): 460-7, 2011 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-21536025

RESUMO

CL-385319, an N-substituted piperidine, is effective in inhibiting infection of H1-, H2-, and to a lesser extent, H3-typed influenza A viruses by interfering with the fusogenic function of the viral hemagglutinin. Here we show that CL-385319 is effective in inhibiting infection of highly pathogenic H5N1 influenza A virus in Madin-Darby Canine Kidney (MDCK) cells with an IC50 of 27.03±2.54 µM. This compound with low cytotoxicity (CC50=1.48±0.01 mM) could also inhibit entry of pseudoviruses carrying hemagglutinins from H5N1 strains that were isolated from different places at different times, while it had no inhibitory activity on the entry of VSV-G pseudotyped particles. CL385319 could not inhibit N1-typed neuraminidase activity and the adsorption of H5-typed HA to chicken erythrocytes at the concentration as high as 1 mg/ml (2.8 mM). Computer-aid molecular docking analysis suggested that CL-385319 might bind to the cavity of HA2 stem region which was known to undergo significant rearrangement during membrane fusion. Pseudoviruses with M24A mutation in HA1 or F110S mutation in HA2 were resistant to CL-385319, indicating that these two residues in the cavity region may be critical for CL-385319 bindings. These findings suggest that CL-385319 can serve as a lead for development of novel virus entry inhibitors for preventing and treating H5N1 influenza A virus infection.


Assuntos
Antivirais/farmacologia , Hidrocarbonetos Fluorados/farmacologia , Virus da Influenza A Subtipo H5N1/efeitos dos fármacos , Virus da Influenza A Subtipo H5N1/fisiologia , Piperidinas/farmacologia , Internalização do Vírus/efeitos dos fármacos , Animais , Antivirais/metabolismo , Antivirais/toxicidade , Benzamidas , Cães , Células HEK293 , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Humanos , Hidrocarbonetos Fluorados/metabolismo , Hidrocarbonetos Fluorados/toxicidade , Virus da Influenza A Subtipo H5N1/metabolismo , Modelos Moleculares , Piperidinas/metabolismo , Piperidinas/toxicidade , Conformação Proteica
17.
Neurogastroenterol Motil ; 23(7): e282-93, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21303432

RESUMO

BACKGROUND: Lumenal glucose initiates changes in gastrointestinal (GI) function, including inhibition of gastric emptying, stimulation of pancreatic exocrine and endocrine secretion, and intestinal fluid secretion. Glucose stimulates the release of GI hormones and 5-hydroxytryptamine (5-HT), and activates intrinsic and extrinsic neuronal pathways to initiate changes in GI function. The precise mechanisms involved in luminal glucose-sensing are not clear; studying gut endocrine cells is difficult due to their sparse and irregular localization within the epithelium. METHODS: Here we show a technique to determine activation of gut epithelial cells and the gut-brain pathway in vivo in rats using immunohistochemical detection of the activated, phosphorylated, form of calcium-calmodulin kinase II (pCaMKII). KEY RESULTS: Perfusion of the gut with glucose (60 mg) increased pCaMKII immunoreactivity in 5-HT-expressing enterochromaffin (EC) cells, cytokeratin-18 immunopositive brush cells, but not in enterocytes or cholecystokinin-expressing cells. Lumenal glucose increased pCaMKII in neurons in the myenteric plexus and nodose ganglion, nucleus of the solitary tract, dorsal motor nucleus of the vagus and the arcuate nucleus. pCaMKII expression in neurons, but not in EC cells, was significantly attenuated by pretreatment with the 5-HT(3) R antagonist ondansetron. Deoxynojirimycin, a selective agonist for the putative glucose sensor, sodium-glucose cotransporter-3 (SGLT-3), mimicked the effects of glucose with increased pCaMKII in ECs and neurons; galactose had no effect. CONCLUSIONS & INFERENCES: The data suggest that native EC cells in situ respond to glucose, possibly via SGLT-3, to activate intrinsic and extrinsic neurons and thereby regulate GI function.


Assuntos
Encéfalo/fisiologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/fisiologia , Estado de Consciência/fisiologia , Trato Gastrointestinal/fisiologia , Glucose/farmacologia , Mucosa Intestinal/fisiologia , Transdução de Sinais/efeitos dos fármacos , 1-Desoxinojirimicina/farmacologia , Animais , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/efeitos dos fármacos , Células Enterocromafins/citologia , Células Enterocromafins/fisiologia , Glucosamina/análogos & derivados , Glucosamina/farmacologia , Mucosa Intestinal/citologia , Masculino , Modelos Animais , Plexo Mientérico/fisiologia , Ondansetron/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores 5-HT3 de Serotonina/efeitos dos fármacos , Receptores 5-HT3 de Serotonina/fisiologia , Antagonistas da Serotonina/farmacologia , Transdução de Sinais/fisiologia , Proteínas de Transporte de Sódio-Glucose/efeitos dos fármacos , Proteínas de Transporte de Sódio-Glucose/fisiologia
18.
PLoS One ; 5(10): e13757, 2010 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-21060798

RESUMO

BACKGROUND: Pregnant women infected by the pandemic influenza A (H1N1) 2009 virus had more severe disease and higher mortality but its pathogenesis is still unclear. PRINCIPAL FINDINGS: We showed that higher mortality, more severe pneumonitis, higher pulmonary viral load, lower peripheral blood T lymphocytes and antibody responses, higher levels of proinflammatory cytokines and chemokines, and worse fetal development occurred in pregnant mice than non-pregnant controls infected by either wild type (clinical isolate) or mouse-adapted mutant virus with D222G substitution in hemagglutinin. These disease-associated changes and the lower respiratory tract involvement were worse in pregnant mice challenged by mutant virus. Though human placental origin JEG-3 cell line could be infected and proinflammatory cytokines or chemokines were elevated in amniotic fluid of some mice, no placental or fetal involvement by virus were detected by culture, real-time reverse transcription polymerase chain reaction or histopathological changes. Dual immunofluorescent staining of viral nucleoprotein and type II alveolar cell marker SP-C protein suggested that the majority of infected alveolar epithelial cells were type II pneumocytes. CONCLUSION: The adverse effect of this pandemic virus on maternal and fetal outcome is largely related to the severe pulmonary disease and the indirect effect of inflammatory cytokine spillover into the systemic circulation.


Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Mutação , Infecções por Orthomyxoviridae/fisiopatologia , Animais , Anticorpos Antivirais/biossíntese , Quimiocinas/metabolismo , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/fisiologia , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/mortalidade , Infecções por Orthomyxoviridae/virologia , Gravidez , Linfócitos T/imunologia , Carga Viral , Replicação Viral
19.
Exp Biol Med (Maywood) ; 235(8): 981-8, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20660098

RESUMO

Although the majority of infections by the pandemic influenza H1N1 (2009) virus is mild, a higher mortality occurs in young adults with no risk factors for complications. Some of these severe cases were infected by the virus with an aspartate to glycine substitution at 225 position (D225G, H3 numbering) in the hemagglutinin (HA). Previous studies with the highly virulent 1918 pandemic H1N1 virus suggested that such substitution was associated with a dual binding specificity of the virus for both alpha2,3- and alpha2,6-linked sialic acid receptors on host cells. Thus, the D225G mutant may cause more severe disease with its increased predilection for the lower respiratory tract, where the alpha2,3 sialic acid receptor is more prevalent, but this hypothesis has not been investigated. We obtained a mutant virus after four sequential passages in lungs of BALB/c mice with a wild-type pandemic influenza A H1N1 (2009) virus. One plaque purified mutant virus had a single non-synonymous D225G mutation in the HA gene. This mutant was more lethal to chick embryo and produced a viral load of about two log higher than that of the wild-type parental virus during the first 24 h. A pathogenicity test showed that the 50% lethal dose in mice (LD50) was reduced from over 2 x 10(6) plaque-forming units (PFU) with the parental virus to just 150 PFU with the mutant virus. The survival of mice challenged with the mutant virus was significantly decreased when compared with the parental virus (P < 0.0001). Significantly higher viral titers and elevated proinflammatory cytokines in lung homogenates of mice infected with the mutant virus were found, which were compatible with severe histopathological changes of pneumonitis. The only consistent mutation in the genomes of viral clones obtained from dying mice was D225G substitution.


Assuntos
Surtos de Doenças , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Vírus da Influenza A Subtipo H1N1/patogenicidade , Influenza Humana/epidemiologia , Influenza Humana/virologia , Mutação/genética , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Arginina/química , Arginina/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Mediadores da Inflamação/metabolismo , Vírus da Influenza A Subtipo H1N1/genética , Leucina/química , Leucina/genética , Pulmão/metabolismo , Pulmão/virologia , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Ácido N-Acetilneuramínico/metabolismo , Receptores Virais/metabolismo , Fatores de Tempo , Virulência/genética
20.
Immunogenetics ; 61(6): 423-30, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19488747

RESUMO

The antiviral cascade triggered by interferon-gamma (IFN-gamma) represents a vital event for eradicating hepatitis B virus (HBV) in experimental animals. IFN-gamma signaling is mediated through the ligand binding to IFN-gamma receptor 1 (IFNGR1). Control of IFNGR1 expression level is one of the mechanisms by which cells modulate the potency of IFN-gamma signaling. In this study, we comprehensively investigated the single nucleotide polymorphisms (SNPs) in IFNGR1 gene and correlated their occurrence to susceptibility to HBV infection in a Chinese population. A total of 983 participants, including 361 chronic hepatitis B patients, 256 individuals who had spontaneously recovered from HBV infection, and 366 healthy control subjects, were enrolled in the study. Polymerase chain reaction-restriction fragment length polymorphism was used to identify seven SNPs (-611A/G, -56C/T, 40G/A, 95C/T, 130A/G, 20685A/G, 21227T/C) in IFNGR1 gene. We found that -56C and -56T allele were associated with viral clearance and viral persistence, respectively (P = 0.014). In a reporter-driven assay, we validated that the promoter variant with -56C exhibited a higher transcription level than that with -56T in HepG2 cells in a cell-type-specific pattern. We conclude that a functional -56C/T SNP in IFNGR1 promoter is associated with the clinical outcome of HBV infection in this Chinese population.


Assuntos
Predisposição Genética para Doença , Hepatite B Crônica/genética , Polimorfismo de Nucleotídeo Único , Receptores de Interferon/genética , Linhagem Celular , Linhagem Celular Tumoral , Distribuição de Qui-Quadrado , Frequência do Gene , Genótipo , Células HeLa , Hepatite B Crônica/virologia , Humanos , Modelos Logísticos , Luciferases/genética , Luciferases/metabolismo , Medições Luminescentes , Razão de Chances , Regiões Promotoras Genéticas/genética , Análise de Sequência de DNA , Transfecção , Receptor de Interferon gama
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