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1.
JCI Insight ; 9(5)2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38319716

RESUMO

Pattern recognition receptor responses are profoundly attenuated before the third trimester of gestation in the relatively low-oxygen human fetal environment. However, the mechanisms regulating these responses are uncharacterized. Herein, genome-wide transcription and functional metabolic experiments in primary neonatal monocytes linked the negative mTOR regulator DDIT4L to metabolic stress, cellular bioenergetics, and innate immune activity. Using genetically engineered monocytic U937 cells, we confirmed that DDIT4L overexpression altered mitochondrial dynamics, suppressing their activity, and blunted LPS-induced cytokine responses. We also showed that monocyte mitochondrial function is more restrictive in earlier gestation, resembling the phenotype of DDIT4L-overexpressing U937 cells. Gene expression analyses in neonatal granulocytes and lung macrophages in preterm infants confirmed upregulation of the DDIT4L gene in the early postnatal period and also suggested a potential protective role against inflammation-associated chronic neonatal lung disease. Taken together, these data show that DDIT4L regulates mitochondrial activity and provide what we believe to be the first direct evidence for its potential role supressing innate immune activity in myeloid cells during development.


Assuntos
Citocinas , Recém-Nascido Prematuro , Recém-Nascido , Humanos , Citocinas/metabolismo , Monócitos/metabolismo , Imunidade Inata , Mitocôndrias/metabolismo
2.
Behav Brain Res ; 411: 113386, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34052264

RESUMO

The prion glycoprotein (PrPC) is highly expressed in the nervous system as well as in other organs. Its functional roles in behavior have been examined mainly in non co-isogenic, wild-type and PrPC-deficient mice, which showed both age- and genotype-dependent differences. In general, however, effects of genetic background upon behavioral tests are mostly unclear when applied to aging rodents. The present study aimed to determine the effect of deletion of the prion protein on behavior of isogenic mice across different ages. We disclosed a genotype-dependent behavioral dissociation between either motor or cognitive tests, as a function of both age and test type. Remarkably, we also detected a clear age- and genotype-dependent difference in the variability of performance in a cognitive test. The current findings are relevant for both the interpretation of PrPC-related behavior, as well as for issues of reproducibility in studies of rodent behavior.


Assuntos
Cognição/fisiologia , Atividade Motora/genética , Proteínas Priônicas/metabolismo , Fatores Etários , Envelhecimento/metabolismo , Animais , Animais não Endogâmicos , Encéfalo/metabolismo , Feminino , Genótipo , Masculino , Camundongos , Camundongos Knockout , Atividade Motora/fisiologia , Proteínas Priônicas/genética , Príons/genética , Príons/metabolismo
3.
Front Immunol ; 12: 655027, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34012439

RESUMO

Newborns are frequently affected by mucocutaneous candidiasis. Th17 cells essentially limit mucosal invasion by commensal Candida spp. Here, we sought to understand the molecular basis for the developmental lack of Th17 cell responses in circulating blood neonatal T cells. Naive cord blood CD4 T cells stimulated in Th17-differentiating conditions inherently produced high levels of the interleukin-22 immunoregulatory cytokine, particularly in the presence of neonatal antigen-presenting cells. A genome-wide transcriptome analysis comparing neonatal and adult naïve CD4 T cells ex vivo revealed major developmental differences in gene networks regulating Small Drosophila Mothers Against Decapentaplegic (SMAD) and Signal Transducer and Activator of Transcription 3 (STAT3) signaling. These changes were functionally validated by experiments showing that the requirement for TGF-ß in human Th17 cell differentiation is age-dependent. Moreover, STAT3 activity was profoundly diminished while overexpression of the STAT3 gene restored Th17 cell differentiation capacity in neonatal T cells. These data reveal that Th17 cell responses are developmentally regulated at the gene expression level in human neonates. These developmental changes may protect newborns against pathological Th17 cell responses, at the same time increasing their susceptibility to mucocutaneous candidiasis.


Assuntos
Imunomodulação , Interleucinas/metabolismo , Células Th17/imunologia , Células Th17/metabolismo , Fatores Etários , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Citocinas/biossíntese , Humanos , Recém-Nascido , Ativação Linfocitária/imunologia , Fator de Transcrição STAT3/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Interleucina 22
4.
Front Microbiol ; 11: 602664, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33262753

RESUMO

Female sex workers (FSWs) represent a key population for the acquisition of sexually transmitted infections (STI) due to their social vulnerability and the risks associated with their occupation. This study was conducted to describe the sociodemographic characteristics and sexual behavior among FSWs in cities in northern Brazil, to determine the prevalence of human immunodeficiency virus 1 (HIV-1) and human T-cell lymphotropic virus (HTLV-1/2) infections and to identify the circulating subtypes of these agents in this key population. A cross-sectional study using the Time Location Sampling (TLS) method was conducted among 339 FSWs in cities in the state of Pará from 2005 to 2006. Serological and molecular tests were performed to identify infections and viral subtypes, and bivariate and multivariate analyses were conducted to identify risk factors. Most FSWs were young, single, less educated and had at least one child. The prevalence of antibodies against HIV-1 and HTLV-1 was 2.3 and 1.7%, respectively. HIV-1 subtypes B (87.5%) and F1 (12.5%) were identified among FSWs, as were Cosmopolitan subtype (1a) and Transcontinental subgroup (A). Unprotected sex and illicit drug use were associated with HIV-1 and HTLV-1 infections using bivariate and multivariate analyses, and age ≥27 years was associated only with HIV. The important information highlighted here clearly indicates that the lack of actions to control and prevent pathogens in FSWs and the lack of strategies for health promotion in key populations can further aggravate the epidemiological scenario of viral infections in remote areas with low human development indices. Neglecting these facts may be causing the spread of these two viruses and their respective subtypes in the general population of northern Brazil.

5.
BMC Infect Dis ; 20(1): 129, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32046662

RESUMO

BACKGROUND: Syphilis is a sexually transmitted infection (STI) transmitted from person to person mainly by sexual intercourse or through vertical transmission during pregnancy. Female sex workers (FSWs) are exposed especially to syphilis infection, and besides all the efforts to control the spread of STIs, syphilis prevalence is still rising, mainly occurring in low-income countries. This study aimed to investigate the syphilis prevalence, demographic characteristics and sexual habits among FSWs in the Amazon region of Brazil. METHODS: A cross-sectional study was carried out including 184 FSWs from 3 countryside cities of the state of Pará, Amazon region of Brazil. A venereal disease research laboratory test and an indirect immunoenzyme assay to test antibodies against Treponema pallidum were used for screening syphilis infection, while sexual habits and demographic data information were collected through a semi-structured questionnaire. Data was analyzed comparing groups with/without syphilis. Poisson regression models were used to estimate the reasons of prevalence (RP). RESULTS: The overall prevalence of syphilis was 14.1% (95% CI = 9.8-17.8). FSWs had between 15 and 56 years of age, most were unmarried (65.7%), had attended less than 8 years of formal education (64.1%), had between 10 and 20 partners per week (64.1%), and reported no previous history of STIs (76.1%) and regular use of condom (52.7%). Low level of education attending up to the primary school (RP adjusted = 3.8; 95% CI = 1.4-9.2) and high frequency of anal sex during the past year (RP adjusted = 9.3; 95% CI = 3.5-28.7) were associated with a higher prevalence of syphilis. CONCLUSIONS: A high prevalence of syphilis among FSWs in the Brazilian Amazon region was identified, showing that syphilis is more likely to be transmitted in FSW working in low-income areas, which is attributed to the low level of education. Anal intercourse was found as a risk factor associated with syphilis. Health programs focused on risk populations appear as a rational way to control syphilis spread, which is a rising problem in Brazil and in other several countries.


Assuntos
Profissionais do Sexo/estatística & dados numéricos , Sífilis/epidemiologia , Adolescente , Adulto , Brasil/epidemiologia , Cidades/estatística & dados numéricos , Preservativos/estatística & dados numéricos , Estudos Transversais , Escolaridade , Feminino , Humanos , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Comportamento Sexual/estatística & dados numéricos , Parceiros Sexuais , Sífilis/diagnóstico , Sorodiagnóstico da Sífilis , Treponema pallidum/imunologia , Adulto Jovem
6.
Cell Death Dis ; 10(4): 323, 2019 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-30975983

RESUMO

Harmful environmental stimuli during critical stages of development can profoundly affect behavior and susceptibility to diseases. Alzheimer disease (AD) is the most frequent neurodegenerative disease, and evidence suggest that inflammatory conditions act cumulatively, contributing to disease onset. Here we investigated whether infection early in life can contribute to synapse damage and cognitive impairment induced by amyloid-ß oligomers (AßOs), neurotoxins found in AD brains. To this end, wild-type mice were subjected to neonatal (post-natal day 4) infection by Escherichia coli (1 × 104 CFU/g), the main cause of infection in low-birth-weight premature infants in the US. E. coli infection caused a transient inflammatory response in the mouse brain starting shortly after infection. Although infected mice performed normally in behavioral tasks in adulthood, they showed increased susceptibility to synapse damage and memory impairment induced by low doses of AßOs (1 pmol; intracerebroventricular) in the novel object recognition paradigm. Using in vitro and in vivo approaches, we show that microglial cells from E. coli-infected mice undergo exacerbated activation when exposed to low doses of AßOs. In addition, treatment of infected pups with minocycline, an antibiotic that inhibits microglial pro-inflammatory polarization, normalized microglial response to AßOs and restored normal susceptibility of mice to oligomer-induced cognitive impairment. Interestingly, mice infected with by E. coli (1 × 104 CFU/g) during adolescence (post-natal day 21) or adulthood (post-natal day 60) showed normal cognitive performance even in the presence of AßOs (1 pmol), suggesting that only infections at critical stages of development may lead to increased susceptibility to amyloid-ß-induced toxicity. Altogether, our findings suggest that neonatal infections can modulate microglial response to AßOs into adulthood, thus contributing to amyloid-ß-induced synapse damage and cognitive impairment.


Assuntos
Disfunção Cognitiva/microbiologia , Encefalite/microbiologia , Infecções por Escherichia coli/complicações , Microglia/metabolismo , Sinapses/efeitos dos fármacos , Peptídeos beta-Amiloides , Animais , Animais Recém-Nascidos , Encéfalo/crescimento & desenvolvimento , Encéfalo/imunologia , Encéfalo/microbiologia , Células Cultivadas , Disfunção Cognitiva/induzido quimicamente , Suscetibilidade a Doenças/etiologia , Feminino , Masculino , Camundongos , Microglia/citologia , Microglia/efeitos dos fármacos , Sinapses/metabolismo , Sinapses/patologia , Fatores de Tempo
7.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1491486

RESUMO

Neospora caninum é um protozoário do filo Apicomplexa que causa infecções associadas com aborto, mortalidade neonatal e alterações neurológicas em várias espécies animais. Este estudo, conduzido na área urbana do município de Porto Alegre, Rio Grande do Sul, teve como objetivos: verificar a prevalência de anticorpos classe IgG para N. caninum em cães através da técnica de imunofluorescência indireta (RIFI) e avaliar os fatores de risco relacionados com o manejo e características individuais dos animais, através de questionário epidemiológico. Foram constituídos três grupos de cães: domiciliados (n= 145); errantes (n= 70) e de criatórios comerciais (n=45). A frequência de anticorpos total foi 13,84% (36/260) e entre os grupos foi de 15,8% para domiciliados, 17,1% para errantes e 2,2% para cães de criatório comerciais. Os títulos sorológicos observados variaram de 50 (44%) a 3200 (3%). Observou-se associação entre a soropositividade e os fatores alimentação (p

8.
Acta amaz ; 32(3)2002.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1454904

RESUMO

In a study conducted to determine natural enemies of coffee berry borer (Hypothenemus hampei, Ferrari) in the state of Rondônia, the occurrence of the fungus Beauveria bassiana (Bals.) Vuill. was identified at Embrapa Rondônia. Coffee fruits with coffee borer containing the fungus were collected in Conilon coffee plantations (Coffea canephora), in Rolim de Moura, Ouro Preto do Oeste and Machadinho do Oeste, state of Rondônia, Brazil, from February to March, 2000. The infection percentage in fruits with coffee berry borer varied from 0.23% to 0.47%, less than reported from other regions of Brazil.


Em trabalho efetuado visando o levantamento de inimigos naturais da broca-do-café (Hypothenemus hampei, Ferrari) no estado de Rondônia, verificou-se a ocorrência do fungo Beauveria bassiana (Bals.) Vuill. conforme identificação da Embrapa Rondônia. Os frutos de café foram coletados em cafezais da cultivar Conilon (Coffea canephora), nos municípios de Rolim de Moura, Ouro Preto do Oeste e Machadinho do Oeste, Rondônia, nos meses de fevereiro a março de 2000. A percentagem média de infecção de B. bassiana em frutos broqueados variou de 0,23% a 0,47%, sendo menor que em outras regiões do Brasil.

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