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Navegando por Orientadores "VASCONCELOS, Pedro Fernando da Costa"

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    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.
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    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.
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    Caracterização genética, correlação antigênica e ecoepidemiológica dos vírus do grupo C (Bunyaviridae, orthobunyavirus) isolados nas américas
    (Universidade Federal do Pará, 2005-02-28) NUNES, Márcio Roberto Teixeira; ROSA, Amélia Paes de Andrade Travassos da; VASCONCELOS, Pedro Fernando da Costa; http://lattes.cnpq.br/0973550817356564
    To date, no molecular studies on group C viruses (Bunyaviridae: Orthobunyavirus) have been published. The current work determined the complete small RNA segment and partial medium RNA segment nucleotide sequences for group C members. The full-length SRNA sequences ranged from 915 to 926 nucleotides in length, and revealed similar organization in comparison with other orthobunyaviruses. Based on the 705 nt of the N gene, group C members were distributed into 3 major phylogenetic groups, with the exception of Madrid virus that was placed outside of these 3 groups. Analysis of the Caraparu virus strain BeH 5546 revealed that it has an SRNA sequence nearly identical to that of Oriboca virus and is a natural reassortant virus. In addition, analysis of 345 nucleotides of the Gn gene for seven group C viruses and for strain BeH 5546 revealed a different phylogenetic topology, suggesting a reassortment pattern among them. These findings represent the first evidence for natural reassortment among the group C viruses, which include several human pathogens. Furthermore, our genetic data corroborate previous antigenic relationships determined using serologic assays (complement fixation, hemagglutination inhibition and neutralization tests), and suggest that a combination of informative molecular, serological and ecological data is a helpful tool to understand the molecular epidemiology of orthobunyavirus.
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    Caracterização molecular dos vírus do grupo Gamboa (Bunyaviridae, Orthobunyavirus) isolados nas américas e infecção experimental em pintos (Gallus gallus domesticus) com o vírus Gamboa cepa Be AN 439546
    (Universidade Federal do Pará, 2010-03-31) CHIANG, Jannifer Oliveira; VASCONCELOS, Pedro Fernando da Costa; http://lattes.cnpq.br/0973550817356564
    Presently, little information on Gamboa serogroup viruses (Bunyaviridae, Orthobunyavirus) is available. Thus, in this work, it was performed a comparative phylogenetic study on the members of the Gamboa serogroup and with other orthobunyaviruses to the level of the gene Gn (M-RNA); an experimental infections in the domestic bird (Gallus domesticus) using the strain Be AN 439546 of the Gamboa Virus (GAMV); and a serologic study using the Hemagglutination Inhibition (HI) test in serum samples of wild animals and humans collected in Tucuruí - Pará. The phylogenetic analysis of Gamboa group viruses demonstrated that they are genetically closely related to group Turlock viruses and less related to the Simbu group viruses. The group Gamboa viruses were distributed in two clades (I and II), that it is in agreement with the current serologic classification; the clade I correspond to the Gamboa complex and the clade II to the Alajuela complex. The strain Be AN 439546 presented tropism for chikens lung and liver, with viral replication in this organs confirmed by detection of viral antigens by immunohistochemistry. These results, demonstrate that this bird species is a susceptible host for GAMV replication. The detection of HI antibodies against GAMV, confirmed by neutralization tests were found in wild bird plasmas and reinforces the hypothesis that these animals constitute the main amplification hosts in the maintenance cycle of GAMV. Full length genome studies of the Gamboa serogroup viruses, as well as on the ecoepidemiology of their vectors and potential vertebrate hosts are needed to generate new data and to reinforce the understanding of the information already existent on those viruses.
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    Caracterização molecular e relação filogenética do genoma completo dos arbovírus Bussuquara, Iguape, Ilhéus e Rocio (Família Flaviviridae, Gênero Flavivirus)
    (Universidade Federal do Pará, 2009-11-27) MEDEIROS, Daniele Barbosa de Almeida; NUNES, Márcio Roberto Teixeira; http://lattes.cnpq.br/0299116892743368; VASCONCELOS, Pedro Fernando da Costa; http://lattes.cnpq.br/0973550817356564
    Flaviviruses have been known due their complex biological cycle and their relevance in public health and global economy. The ecologic aspected and clinic pictures are related with phylogeny and evolution of flaviviruses. This work aims the molecular characterization of Bussuquara (BSQV), Iguape (IGUV), Ilheus (VILH) e Rocio (VROC) flaviviruses genomes, determining their phylogenetic relationships with others members of genus Flavivirus. The study included: the full-length sequencing of the four Brazilian flaviviruses; analyzes of the predictive secondary structure of RNA and conserved sequences in the 3’NCR; determination of cleavage and glicosilation sites, cisteine residues and conserved motifs in the polyprotein; and similarity and phylogenetic analyzes. The BSQV, IGUV, VILH and VROC genomes present 10815 nt, 10922 nt, 10775 nt, and 10794 nt, respectively. The conserved standard sequences in 3’NCR of BSQV was RCS2-CS2-CS1, while to IGUV, ILHV and ROCV were CS3-RCS2-CS2-CS1. The secondary structure of RNA obtained for the Brazilian flaviviruses were similar to the other flaviviruses. The numbers of the glicosilation sites to PrM, E and NS1 proteins were distinct among the studied Brazilian flaviviruses, therefore the pattern 6,12,12 Cis residues and the cleavage sites were conserved. In the E protein, some singles mutations were observed in fusion peptide of BSQV, IGUV and ROCV, and the RGD motif were distinct for the flaviviruses under study. The motif that determines the MTase-SAM activity in NS5, as well as the helicase and protease activity in NS3 were conserved. Among the eight polimerase motifs in NS5, only the V, VI and VII motifs were observed single mutations in ILHV and ROCV. The similarity analyzes showed that BSQV presents high relationship with VIGU, while ILHV and ROV were more related among themselves, however those viruses were considerated distincts species. Based in the phylogenetic analyzes, molecular and biological characteristics, it was proposed the establishment of three distinct genetic groups: the Rocio group, grouping ILHV and ROCV, Bussuquara group formed by BSQV and Naranjal virus; and Aroa group, that include Aroa virus and IGUV.
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    Caracterização morfológica e antigênica do vírus Juruaçá, isolado de morcego no estado do Pará
    (Universidade Federal do Pará, 2006) ARAÚJO, Tais Pinheiro de; VASCONCELOS, Pedro Fernando da Costa; http://lattes.cnpq.br/0973550817356564
    Juruaçá virus (BE AN 401933) was isolated from pooled organs of an unidentified bat captured during field work in Porto Trombetas, Oriximiná, Pará State, in 1982, and remains unclassified/ungrouped. The aims of this work were to classify Juruaçá virus in a viral taxon taking in account its morphological, physicochemical, antigenic and molecular properties, as well as, to describe the pathological alterations. This agent is pathogenic only for infant mice, and the animal’s death occurs with eight days post-inoculation. It’s not related to any of the arthropod borne viruses with which it has been tested by serological tests, such as complement fixation (CF) and hemagglutination inhibition (HI). Positive reactions were only observed with its homologous serum. Juruaçá virus is not sensitive to sodium desoxicolate and can hemagglutinate goose cells at pH 5.75. The virus didn’t show any cytophatic effect and immunofluorescence was negative in Vero and C6/36 cell lines, but it replicates in brain tissue primary culture cell line (astrocytes and microglias), confirmed by immunofluorescent assay (IFA). Culture of neuronal cells appears not to be infected by Juruaçá virus; however, infection of these cells was confirmed by imunohistochemistry. By transmission electron microscopy and negative stain, the virus is a spherical particle, with mean diameter of 23-30nm. Pathological alterations were observed mainly in the central nervous system of newborn mice experimentally infected with Juruaçá virus. The molecular results of RT-PCR suggest that Juruaçá virus is a possible new virus belonging to the family Picornaviridae, genus Enterovirus.
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    Estudo das causas de internação por dengue no Hospital Universitário João de Barros Barreto, período de 1997-2001 Belém-Pará
    (Universidade Federal do Pará, 2004) RIBEIRO, Claudete Teles; VASCONCELOS, Pedro Fernando da Costa; http://lattes.cnpq.br/0973550817356564
    It was evaluated the causes of admission for dengue fever in the Hospital Universitário Joao Barros Barreto in the period of 1997-2001, by means of a retrospective, descritptive and comparative study, in which, among several variable that had been considered, the signals and symptoms presented for the patients when admitting were investigated. It was analyzed the registers in handbooks of 144 cases interned with suspicion of dengue fever. The results demonstrated that the most prevalent symptoms and signs presented were fever, headache, myalgia and arthralgia, that were described among 137 (95%), 117 (81.2%), 93 (64.4%) and 67 (46.5%) patients, respectively. It was observed that internment by dengue fever could be avoided, since patients could be treated at ambulatory level, since no dengue hemorrhagic fever cases were observed. Nonetheless, the trend observed in this study is for a reduction in the number of patients hospitalized as well as in the time in days of hospitalization.
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    Estudo epidemiológico da raiva, caracterização antigênica de cepas do vírus da raiva isoladas na Amazônia brasileira
    (Universidade Federal do Pará, 2009-10-27) CASSEB, Livia Medeiros Neves; ROSA, Elizabeth Salbé Travasos da; http://lattes.cnpq.br/2209576799096027; VASCONCELOS, Pedro Fernando da Costa; http://lattes.cnpq.br/0973550817356564
    Aiming to evaluate the epidemiology of rabies, new diagnostic procedures – antigenic and genetic characterization - were included in this study to investigate the epidemiologic profile of animal rabies in the Brazilian Amazon region, between January 2000 and July 2009. A careful revision of information of Central Nervous System (CNS) samples received and examined at Rabies Laboratory of Instituto Evandro Chagas was performed. A total of 265 rabies virus strains isolated from CNS samples of humans (33) and domestic/sylvatic animals (232) were antigenically characterized by indirect immunofluorescent assay (IFA) using a panel of eight monoclonal antibodies against the rabies virus nucleoprotein produces by the CDC; moreover, from 21 of them the nucleoprotein (gene N) was partially characterized by nucleotide sequencing followed by phylogenetic analyzes. Obtained sequences were compared internally and with other rabies virus sequences from Brazil and other American countries, using the Bayesian and maximum likelihood methods. It was observed a lower transmission of rabies virus in urban areas; the detection of the rural cycle of rabies in almost all Amazonian states; the occurrence of aerial rabies cycle in Pará and Amapá states; identification of rabies virus variant 2 (AgV2) among domestic dogs and cats as the main viral transmission mechanism; detection of circulating antigenic variants AgV3, AgV4 and “Eptesicus” variant in sylvan animals; and finally, reduction of dog-to-man transmission of rabies virus which was replaced by an increasing of bat-to-man transmission cycle, especially in Pará state. In conclusion, the association of antigenic and molecular techniques resulted in a better understanding of rabies molecular epidemiology in the Amazon region.
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    Estudo experimental sobre a resposta imunológica em infecções seqüenciais pelo vírus Dengue 3 e pelo vírus Dengue 2 em primatas não humanos da espécie Callithrix penicillata
    (Universidade Federal do Pará, 2012) FERREIRA, Milene Silveira; VASCONCELOS, Pedro Fernando da Costa; http://lattes.cnpq.br/0973550817356564
    Dengue fever is caused by Dengue virus (DENV - Flaviviridae, Flavivirus) and is considered the most widespread arbovirus in the world. Currently, there is an animal that fits a model for studies on the pathogenesis of DENV. To investigate the susceptibility of the DENV Callithrix penicillata were inoculated samples DENV-3 and DENV-2 isolated from human cases of fatal. To do this, twenty-two animals were infected with DENV-3 (3.23 × 103 PFU/mL) and sixty days after infection (dai), 11 of these were secondarily infected with DENV-2 (4.47 × 104 PFU/mL). Blood, plasma and serum were collected daily during the first seven days and for 15, 20, 45, and 60 dai. We investigated the production of IgM antibodies and inhibitors of hemagglutination (HI), as setup were analyzed biochemical and hematological profile and serum cytokine levels (IL-6, TNF- α, IL-2, IFN-, IL-4 and IL-5). Primary infection (DENV-3) showed IgM (15-20 dai), antibodies IH (15-60 dai), increased levels of TNF-α and IFN-γ and decreased IL-5. In secondary infection (DENV-2) was detected IgM antibodies (15-20 dai), antibodies HI (15-60 dai), and decreased levels of IL-6, TNF-α, IFN-γ and IL-5. Furthermore, it was observed in both infections leukopenia, neutropenia, lymphocytopenia, monocytopenia, thrombocytopenia, and increased AST. The high levels of INF-γ and TNF-α showed activation of the inflammatory response, as the response to cellular differentiation and suppression of proliferation of cytokine features of the humoral response. The presence of neutralizing antibodies may have caused suppression of the inflammatory response in secondary infection which may have led to the absence of signs of Dengue Hemorrhagic Fever/Dengue Shock Syndrome (DHF/DSS) during secondary infection (DENV-2). The results indicate that non-human primates Callithrix penicillata demonstrated susceptibility to DENV strains of human origin, suggesting that these animals are a good model for studies of the immune response of Dengue Fever (DF) and for the assessment of a tetravalent vaccine.
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    Imunopatologia experimental do vírus da raiva, com as variantes antigênicas 2 e 3
    (Universidade Federal do Pará, 2015-06-02) CASSEB, Livia Medeiros Neves; VASCONCELOS, Pedro Fernando da Costa; http://lattes.cnpq.br/0973550817356564
    The rabies is considered a zoonosis due have as host, reservoirs and transmitters the domestic or wild mammals. It´s characterized in acute disease caused by rabies virus (RABV) that affects the central nervous system (CNS) characterized by encephalitis with fatal prognosis in almost all cases, in any mammalian species. The aim of this study was to describe pathological findings and immunopathology of different strains of rabies virus in the tissues of the central nervous system, checking cellular and humoral immune response during experimental infection of Mus musculus mice. The animals were inoculated with two antigenic variants of RABV (VAg2 and VAg3), by different routes of infection, and a control group. The animals were observed for development of clinical signs and symptoms, collected and euthanized following a kinetic. The tissues were fixed in formaldehyde 10%, embedded in paraffin, stained with hematoxylin-eosin for histopathological analysis and with specific antibodies for immunohistochemical to characterize and quantify in situ distribution of the antigen and the inflammatory response. RABV antigens were found in the CNS in a diffuse way, but mainly in neurons. It was observed suppression of CD4+ lymphocytes, with increase of CD8+ lymphocytes. It was observed significant apoptosis with glial cell death and an increase of proinflammatory cytokines (TNF-α, IFN-γ, IL-6, IL-1β and IL-8), anti-inflammatory (TGF-β and IL-4) and iNOS in both antigenic variants of RABV, but without observation of a TH17 profile. The analyses enable the characterization of rabies as meningoencephalitis, since it affects the meningeal, perivascular and intraparenchymal microenvironments. And the inflammatory process was observed even in the presence of inclusion bodies, but with less intensity.
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    Imunopatologia hepática da infecção experimental do vírus dengue em Callithrix penicillata
    (Universidade Federal do Pará, 2015-09-25) HENRIQUES, Daniele Freitas; VASCONCELOS, Pedro Fernando da Costa; http://lattes.cnpq.br/0973550817356564
    Dengue is one of most important public health problem in the world, and one of the factors that contribute with this situation is the lack of an effective vaccine against the disease, and in part, this difficulty to obtain is due clinical the lack of an experimental model that mimic the infection and manifestation of the disease as those observed in humans. Then, the Evandro Chagas Institute showed the presence of dengue antigens using the Immunohistochemistry assay, in the liver of a non-human primate (NHP) of the species Callithrix jacchus, with a fatal outcome following dengue hemorrhagic fever. Based in the above considerations and in addition to the fact that the liver is the targetb organ for Dengue Virus (DENV) in humans, it is important to analyze the liver of primates of the genus Callithrix in order to study the pathogenesis and the immunopathology of sequential infection by DENV. A total of 26 NHP Callithrix penicillata were submitted to primary infection (PI) subcutaneously with DENV-3 (3.23 x 103 PFU/mL), and 13 of these animals anesthetized and sacrificed daily for seven days post-infection (dpi) (acute phase) and in random intervals until 60 dpi (convalescent phase); the secondary infection (SI) with DENV-2 (4.47 x 104 PFU/mL) was performed two months after the PI in the remaining 13 animals. Uninfected sentinels animals were reserved up ending of the experiment. The liver of the animals were processed for histopathology and Immunohistochemical assay using polyclonal antibodies to DENV and antibodies for analyses of the innate and cellular immune response as well as the cytokine expression . The NHP were susceptible to sequential infection by DENV-3 and DENV-2; in the liver viral antigens were expressed in hepatocytes, Kupffer cells and Councilman bodies; the histopathological changes in liver was characterized by the presence of apoptosis, focal lytic necrosis, steatosis, swelling cellular, inflammation (acinar, EP and HCV), hyperplasia/hypertrophy in Kupffer cells, hemosiderin in Kupffer cells and sinusoidal dilatation; the intensity of the liver damage was prominent in the acute phase of PI and SI resulting in acute hepatitis. In addition the apoptosis was the most frequent mechanism of death of hepatocytes; lytic necrosis and inflammatory infiltrate showed predominant distribution pattern in Z2. An increase of the acinar expression of activated macrophages, NK cells, S-100 protein and B-lymphocytes during the stages of PI and SI; as well as, increased acinar expression of TCD4 + lymphocytes during the acute phase of PI; as to the quantification of cytokines and molecules, was observed an increase in acinar expression of: IFN- during the stages of PI and SI, TNF-α and IL-8 with higher prevalence in SI, TGF-β and IL-10 with prevalence in acute phase of PI, Fas protein during the acute phase of PI and SI and VCAM in acute phase of SI, as well as increase in expression in the EP. These findings were similar to those observed in livers from fatal cases of dengue fever in humans, but with lower intensity and amplitude, thus indicating that NHP Callithrix penicillata species is a good experimental model for infection by DENV, involving immunopathologic studies.
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    Infecção persistente pelos flavivírus Ilhéus e Rocio em hamsters dourados jovens (Mesocricetus auratus)
    (Universidade Federal do Pará, 2009-08-28) HENRIQUES, Daniele Freitas; VASCONCELOS, Pedro Fernando da Costa; http://lattes.cnpq.br/0973550817356564
    Ilheus (ILHV) and Rocio (ROCV) are flaviviruses (family Flaviviridae, genus Flavivirus) of great importance to public health in Brazil because these viruses are associated to encephalitis cases in humans. Recent studies have reported persistence of experimental infections (in vivo and in vitro) and clinical reports. The purpose of this study was to investigate in vivo the possible occurrence of persistent infection caused by ILHV and ROCV using young golden hamsters (Mesocricetus auratus) as experimental model. Hamsters were inoculated intraperitoneally with a suspension of brains of newborn mice infected with titers of 9.8 and 9.6 DL50/ 0.02 mL of ROCV and ILHV respectively, and at pre-determined intervals, they were anesthetized and sacrificed for collection of blood samples, serum and urine and organ fragments during four months (120 days) post-inoculation (p.i.). Viral quantification was calculated in samples of brain, liver and blood, using the technique of Real Time RT-PCR (qRT-PCR). All collected specimens were inoculated into VERO cells for confirmation of viral replication; and viral antigens in the cell cultures were detected by indirect immunofluorescence test; the levels of antibodies were determined by hemagglutination-inhibition test. Histopathological examination by hematoxylin-eosin and detection of viral antigens by imunohistochemistry were assayed in viscera and central nervous tissue samples collected during the kinetics. The study showed that young golden hamsters are good experimental model for persistent infection by the flaviviruses ILHV and ROCV. Both viruses induced strong immune response, although the levels of antibodies to ILHV were greater than for ROCV. The ROCV has demonstrated to be more pathogenic in these animals, suggesting higher ability to cause neuronal invasiveness than ILHV. Infected viscera samples inoculated in VERO cells resulted in growth of both viruses from all infected organ, blood, serum and urine samples and were confirmed by indirect immunofluorescence assay. Regarding persistence of infection, ROCV was detected in the brain, liver and blood by qRT-PCR, for three months p.i., while ILHV persistence was observed only in the brain for 30 days p.i. by qRT-PCR. The ROCV was able to produce histopathological changes, and immuno-labeled cells expressing viral antigens in liver, kidney, lung and brain samples during four month were confirmed by imunohistochemistry. To the ILHV, the histopathological changes and expression of viral antigens in samples from the liver, kidney and lung were only confirmed up to 30 days p.i., but the brain was positive for four months p.i.; The findings obtained in this study showed that both viruses have capacity to cause persistent infection in hamsters intraperitoneally infected, studies additional are needed to determine the pathophysiology and pathogenesis of ILHV and ROCV persistent infections.
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    Soroprevalência de anticorpos e padronização do teste ELISA sanduíche indireto para 19 tipos de arbovírus em herbívoros domésticos
    (Universidade Federal do Pará, 2010-09-30) CASSEB, Alexandre do Rosário; VASCONCELOS, Pedro Fernando da Costa; http://lattes.cnpq.br/0973550817356564
    The brazilian Amazon region maintains the largest variety of arboviruses and the state of Pará is responsible for 26% of this territory, so the major goal of this work was to determine the prevalence and distribution of HI antibodies to 19 domestic arbovirus in domestic herbivores in the state of Pará and to standardize an indirect sandwich IgG ELISA test to serum samples of equines, cattle, buffaloes and sheep. In all species studied and throughout the State of Pará a large prevalence of HI antibodies to all arbovirus analyzed was observed and SLEV, ILHV, EEEV, MAGV and WEEV, showed higher prevalence, where the SLEV was the most prevalent. Regarding the virus families HI antibodies to MAGV was the most prevalent Bunyaviridae in all species, the most prevalent Flaviviridae was SLEV in all species and in the family Togaviridae the EEEV was more prevalent in horses. In order to analyze the prevalence of HI antibodies by animal species was observed that horses did not show significant differences compared to buffaloes, however, showed significant difference compared to cattle and sheep; there was not observed significant difference between the ruminant species. Using sandwich indirect IgG ELISA a large number of crossed reactions were found. This enzymatic test can be used to detect IgG antibodies among families of arboviruses studied.
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