Navegando por Agência de fomento "IEC - Instituto Evandro Chagas"

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Acesso aberto (Open Access)
Avaliação da diversidade de insetos hematófagos da subordem Nematocera e de vertebrados silvestres: transmissão de arbovírus na área de influência do Projeto Salobo, Carajás, Pará
(Universidade Federal do Pará, 2009) MONTEIRO, Hamilton Antonio de Oliveira; VASCONCELOS, Pedro Fernando da Costa; http://lattes.cnpq.br/0973550817356564
Aiming to evaluate the diversity of hematophagous insects and sylvan vertebrates, as well as the arbovirus fauna present in the area, a longitudinal study was performed in the Salobo Project area, Mineral Province of Carajas, Pará state, Brazil, between December 2005 and June 2007 (seven scientific expeditions), before the action of mineral extraction be launched. Insects belonging to the families Ceratopogonidae, Culicidae, Psychodidae, and Simulidae were collected using the miniature CDC and Shannon light traps, and human bait; sylvan vertebrates (birds, small mammals and reptilians) were also captured in the are using Shermann and Tommahwak traps. Biological specimens from insects and vertebrates were used to attempt of virus isolation in suckling mice, while the vertebrate serum samples to determine the antibody prevalence to 19 arboviruses by hemagglutination inhibition (HI) tests. A total of 44,795 (1,220 lots) hematophagous insects were collected, mostly of Psychodidae. The most abundant species of Culicidae were Haemagogus leucocelaenus and Haemgogus janthinomys; a total of 1,288 vertebrates were also captured; the rodents Proechimys guyannensis and Oryzomys capito, and the birds Turdus albicolis and Phlegopsis nigromaculata were the most prevalent species in the area. Three Tucunduba virus strains were isolated from lots of Anopheles (Nys.) sp., Culex coronator and Wyeomyia sp. HI antibodies were found to Bussuquara virus, Cacipacore virus, Icoaraci virus, Ilheus virus, Mucambo virus Rocio virus, Saint Louis encephalitis virus (SLEV), and western equine encephalitis virus. The most prevalent arbovirus by HI was the SLEV.
Acesso aberto (Open Access)
Caracterização da resposta imune citocínica na infecção humana pelo vírus oropouche e sua relação com o padrão de soroconversão e a presença de sintomas
(Universidade Federal do Pará, 2011-12-19) OLIVEIRA, Euzébio de; VASCONCELOS, Pedro Fernando da Costa; http://lattes.cnpq.br/0973550817356564
This thesis is the first global study that researches and analyzes the immune response of cytokine in human infections by Orthobunyavirus Oropuche virus. The study used 320 samples of human serum. Sixty were from the Blood Bank (negative control) and 260 were obtained from two outbreaks of the Oropouche virus in the State of Pará and Amapá (Brazil). The latter was divided into 8 subgroups for better data accuracy. The collected samples were analyzed for clinical data/symptoms with serologic testing by titration of antibodies by the hemagglutination inhibition (IgM/IgG) and the detection cytokines plasma levels by flow cytometry. This allowed for the technical description of cytokine. The data obtained allowed for the observation of the characteristics and the behavior of the cytokines signatures expressed by patients by the presence or not of the virus. This also allowed for the observation of changes to serum through the presence of specific symptoms such as fever, chills, headache and dizziness. This led to the following conclusions a) there is a pattern in the synthesis of pro-inflammatory and regulatory cytokines; b) there is a balance in the profile of the immune response between pro-inflammatory cytokines (Th1) and modulators (Th17); c) an infection by the Oropouche virus alters the production of cytokines in individuals; d) the results also show that whem comparing individuals no responders with early responders, there was an increase of IL-1β and decreased IL- 12; no responders with late responders, there was a decrease of IL-8, and increased IFN-α, IL-23 and IL-17; No responders occurred early responders compared with the increase IL-4 and IFN-g; However, when compared early responders and late responders, decreased IFN-α and IL-6; early responders generally showed a decrease in IL-10 and late responders showed an increase in IL-5; e) The results also show the expression of IL-5 in patients who showed symptoms specific for Oropouche infection (fever, chills, headache and dizziness), suggesting this signal to be directly associated with pathogenesis of the virus; f) there is a need to complement this research with more studies such as those related to the expression of chemokines.
Acesso aberto (Open Access)
Efeitos protetores da prolactina em cultivo glial de córtex de ratos expostos ao metilmercúrio
(Universidade Federal do Pará, 2008-04-04) SANTOS, Andréa Cristina Monteiro dos; DINIZ, Domingos Luiz Wanderley Picanço; http://lattes.cnpq.br/9601463988942971
Methylmercury (MeHg) is a compound highly neurotoxic and its degenerative mechanisms are not very clear yet. In Central Nervous System, MeHg is mostly uptake by astrocytes, decreasing neuronal exposition. Studies demonstrated that prolactin (PRL) has mitogenic effects on astrocytes and it can regulate pro-inflammatories cytokines expression. The aim of this work was to verify the protective effects of PRL on disturbs provoked by MeHg on cellular viability, morphology, GFAP (glial fibrillary acidic protein) expression, mitogenesis and release of interleukin-1β in glia primary culture of cerebral cortex of newborn rats, with astrocytes in focus. Glia primary culture were exposed to differents concentrations of MeHg (0,1, 1, 5 e 10 μM) in differents time intervals (2, 4, 6, 18 e 24 h) in medium with fetal bovine serum 10%. Results demonstrated progressive decreasing of 20% e 62% on cellular viability after exposed to 5 e 10 μM MeHg for 24 h, respectively, by MTT [3- (4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay and disturbs in the GFAP expression and distribution. Differents concentrations of PRL (0.1, 1 e 10 nM) were added in free serum medium to evaluate it proliferative action. This was confirmed by mitogenesis induction around 4.5x in 18h at 10 mM PRL. In this conditions (free serum) were evaluated the effects of co-treatment of 1 nM PRL + 5 μM MeHg on cellular viability, morphology, GFAP expression, mitotic index and release of IL-1β. PRL attenuated disturbs caused by MeHg, increasing viability in 33%, GFAP expression, cellular proliferation (4x), and attenuating morphologic alterations like nuclear picnosis and lisis. These findings prove that PRL can act like a cytoprotective agent in primary culture of glia, particularly in astrocytes, in addition to its mitogenic effects.
Acesso aberto (Open Access)
Estudo da neuropatologia induzida pelo vírus Marabá em modelo murino
(Universidade Federal do Pará, 2014-02-28) FARIAS, Alexandre Maia de; DINIZ, Cristovam Wanderley Picanço; http://lattes.cnpq.br/2014918752636286; DINIZ JUNIOR, José Antônio Picanço; http://lattes.cnpq.br/3850460442622655
The Marabá virus (Be AR 411459) is an Vesiculovirus (VSV), member of the Rhabdoviridae family, isolated in 1983 from a pool of sandflies captured in Marabá - PA by Section Arbovirus the Evandro Chagas Institute. In literature There are few studies on experimental neuropathology Marabá virus induced, despite 30 years of isolation. A single study, however, revealed that viral infection in newborn mice causes necrosis and pyknosis in neurons in several regions of the central nervous system (CNS). The objective of this study was to investigate the distribution of Marabá virus in the CNS, reactive microglia and astrocytes, histopathologic features, and the expression of cytokines and nitric oxide (NO), in Marabá virus-induced encephalitis in BALB / c mice. Thus was performed processing of samples for histopathological examination; Immunohistochemistry for observation of microglia, astrocytes and viral antigen; tests for quantification of cytokines and NO, and statistical analyzes. The results showed that infected animals (Ai) 3 days after inoculation (d.p.i.) with discrete labeling of viral antigen, as well as the activation of microglia and astrocytes in the CNS. Moreover , in Ai 6 d.p.i. marking the viral antigen was observed in almost all brain regions, with intense microglial activation in these locations, although was less astrogliosis. Edema, necrosis and apoptosis of neurons were mainly observed in the olfactory bulb, septum and frontal cortex of Ai 6 d.p.i. Quantification of IL - 12p40, IL- 10, IL- 6, TNF- α, INF- ү, MCP-1 and NO, showed significant increases in Ai 6 d.p.i., when compared with controls animals and Ai 3 d.p.i. On the other hand, TGF-β, important immunosuppressant, has not been significant in all groups and evaluated times (3 and 6 d.p.i.). These results indicate that Marabá virus can infect various CNS regions of BALB /c mouse adult 6 d.p.i., producing anatomical and pathological changes and strong inflammatory immune response that can be lethal to the animal.
Acesso aberto (Open Access)
Perfil de MicroRNAs hepáticos pode regular apoptose, lesões vasculares e inflamação na dengue hemorrágica
(Universidade Federal do Pará, 2016-06-30) OLIVEIRA, Layanna Freitas de; BURBANO, Rommel Mario Rodriguéz; http://lattes.cnpq.br/4362051219348099
Dengue is the most prevalent arbovirosis in the world caused by Dengue virus (DENV) and is present in all continents, for more than three decades has been a constant public health concern and often fatal by dengue hemorrhagic fever (DHF). The pathogenesis of dengue is closely related to the host immune response, reaching exacerbated inflammation and transient autoimmunity. All tissues are affected, which liver is one of the most important in severe conditions, due its intense viral replication and its significant role in metabolism. The study of microRNAs (miRNA) as regulatory elements of metabolism and immune response during infection is crucial to understanding the regulatory mechanisms of gene expression on DENV infection, and can help in diagnostic development of anti-viral therapies. We sequenced the miRNoma in MySeq platform (Illumina) to identify the miRNAs profile expressed in FFPE liver tissue, ten DHF fatal cases were compared to five control cases. Eight miRNAs exhibited differential expression in DHF liver, miR-126-5p, a regulatory molecule of endothelial cells, and miR-133a-3p are upregulated in dengue and miR-122-5p, a liver-specific miRNA, miR- 146a-5p, interferon regulator, miR-10b-5p, miR-204-5p, miR-148a-5p and miR-423-5p were downregulated. Functional analysis of KEGG pathways and GO terms with predicted target genes of overexpressed miRNAs found regulatory pathways of apoptosis and immune response, involving MAPK gene, RAS, CDK and FAS; immune response pathways showed NF- kB, CC and CX families, IL and TLR. The same analysis with target genes of downregulated miRNAs also identified in most pathways of apoptosis and biosynthetic pathways of metabolism. In our knowledge, this is the first description of the liver miRNA profile in DHF, the results together show a feasible relationship of miR-126-5p, miR-122-5p and miR-146a-5p with liver pathogenesis of DHF, through endothelial repair and vascular permeability regulation, control of homeostasis and liver expression regulation of inflammatory cytokines.
Acesso aberto (Open Access)
Pesquisa epidemiológica e molecular do vírus respiratório sincicial humano (VSRH) em amostras de pacientes hospitalizados com pneumonia, na cidade de Belém
(Universidade Federal do Pará, 2011-11-17) LAMARÃO, Letícia Martins; LINHARES, Alexandre da Costa; http://lattes.cnpq.br/3316632173870389
Childhood pneumonia and bronchiolitis is a leading cause of illness and death in young children worldwide with Respiratory Syncytial Virus (RSV) as the main viral cause. RSV has been associated with annual respiratory disease outbreaks and bacterial co-infection has also been reported. This study is the first RSV study in young children hospitalized with community-acquired pneumonia (CAP) in Belém city, Pará (Northern Brazil). It had the objective of determining the prevalence of RSV infection and evaluating the patients’ clinical and epidemiological features. Methods. We conducted a prospective study across eight hospitals from November 2006 to October 2007. In this study, 1,050 nasopharyngeal aspirate samples were obtained from hospitalized children up to the age of three years with CAP, and tested for RSV antigen by direct immunofluorescence assay and by Reverse Transcription Polymerase Chain Reaction (RT-PCR) for RSV subtype identification. Levels of C-reactive protein (CRP) and results of bacterial infection were also obtained. Results. RSV infection was diagnosed in 243 (23.1%) children. The mean age of the RSV-positive group was lower than the RSV-negative group (12.1 months vs 15.5 months, both ranged 1-36 months, p<0.001) whereas gender distribution was similar. The RSV-positive group showed lower CRP mean levels when compared to the RSV-negative group (15.3 vs 24.0 mg/dL, p<0.05). Radiological findings showed that 54.2% of RSV-positive group and 50.3% of RSV-negative group had interstitial infiltrate. Bacterial infection was identified predominantly in the RSV-positive group (10% vs 4.5%, p<0.05). Rhinorrhea and nasal obstruction were predominantly observed in the RSV-positive group. A co-circulation of subtypes A and B was noted, with a predominance of subtype B (209/227). Multivariate analysis revealed that age under 1 year (p<0.015), CRP levels under 48 mg/dL (p<0.001) and bacterial co-infection (p<0.032) were independently associated with the presence of RSV as opposed to RSV-negative group, and in analyze of symptoms, nasal obstruction were independently associated with RSV-positive group (p<0.001). Conclusion. The present study highlights the relevance of RSV infection in hospitalized cases of CAP in our region; our findings warrant the conduct of further investigations which can help design strategies for controlling the disease.
Acesso aberto (Open Access)
Situação imunológica dos profissionais de saúde de um laboratório de pesquisa em relação ao vírus da hepatite B
(Universidade Federal do Pará, 2009-08-27) OLIVEIRA, Candida Maria Abrahão de; NUNES, Márcio Roberto Teixeira; http://lattes.cnpq.br/0299116892743368
Hepatitis B is a serious problem of public health, in particular for health-workers, who have an increased risk of acquiring this disease, through contact with patients or infected materials, following accidents and, frequently, in the lack of preventive measures. The object of this study was to determine the prevalence by serologic markers of infection with hepatitis B virus, among workers of a research institute, by way of a descriptive and epidemiological study. 528 samples of blood were collected, during January - April, 2008, in order to analyse serologic markers of hepatitis B by immunnoenzimatic techniques, which detected a total prevalence of 39,7% for some marker of HBV, with 0,4% by HBsAg+; 8% by anti-HBc+/HBs+; 2,5% isolated anti-HBc+ and 28,8% by isolated anti-HBs+. Among the individuals interviewed 31,6%, they were vaccinated against hepatitis B, having among than 38,9% individuals with no response to the vaccine and 80,8% susceptible, made up of non-vaccinated individuals, those not responding to vaccination. These results indicate showed the necessity to carry out Regulation 32, of the Ministry of Work and Employment, protects the health-worker.