Área de PDI em Pesquisa, Desenvolvimento e Inovação em Dengue, Febre Amarela e outras Arboviroses 2013
Veja, abaixo, a relação de artigos científicos publicados pelo IOC, na referida Área Temática, organizados em ordem alfabética crescente:
| Azevedo AS, Goncalves AJS, Archer M, Freire MS, Galler R and Alves AMB (2013), "The Synergistic Effect of Combined Immunization with a DNA Vaccine and Chimeric Yellow Fever/Dengue Virus Leads to Strong Protection against Dengue", Plos One., March, 2013. Vol. 8(3), pp. e58357. Public Library Science. [DOI] |
| Abstract: The dengue envelope glycoprotein (E) is the major component of virion surface and its ectodomain is composed of domains I, II and III. This protein is the main target for the development of a dengue vaccine with induction of neutralizing antibodies. In the present work, we tested two different vaccination strategies, with combined immunizations in a prime/booster regimen or simultaneous inoculation with a DNA vaccine (pE1D2) and a chimeric yellow fever/dengue 2 virus (YF17D-D2). The pE1D2 DNA vaccine encodes the ectodomain of the envelope DENV2 protein fused to t-PA signal peptide, while the YF17D-D2 was constructed by replacing the prM and E genes from the 17D yellow fever vaccine virus by those from DENV2. Balb/c mice were inoculated with these two vaccines by different prime/booster or simultaneous immunization protocols and most of them induced a synergistic effect on the elicited immune response, mainly in neutralizing antibody production. Furthermore, combined immunization remarkably increased protection against a lethal dose of DENV2, when compared to each vaccine administered alone. Results also revealed that immunization with the DNA vaccine, regardless of the combination with the chimeric virus, induced a robust cell immune response, with production of IFN-c by CD8+ T lymphocytes. |
BibTeX: @article{Azevedo2013, author = {Azevedo, A. S. and Goncalves, A. J. S. and Archer, M. and Freire, M. S. and Galler, R. and Alves, A. M. B.}, title = {The Synergistic Effect of Combined Immunization with a DNA Vaccine and Chimeric Yellow Fever/Dengue Virus Leads to Strong Protection against Dengue}, journal = {Plos One}, publisher = {Public Library Science}, year = {2013}, volume = {8}, number = {3}, pages = {e58357}, doi = {10.1371/journal.pone.0058357} } |
| Belinato TA, Martins AJ, Lima JBP and Valle D (), "Effect of triflumuron, a chitin synthesis inhibitor, on Aedes aegypti, Aedes albopictus and Culex quinquefasciatus under laboratory conditions", Parasites & Vectors. [DOI] |
| Abstract: Background: Resistance to traditional insecticides represents a threat to the control of disease vectors. The insect growth regulators (IGR) are a potential alternative to control mosquitoes, including resistant populations. The chitin synthesis inhibitors (CSI) are IGRs, which interfere with the insect molting process and represent one major class of compounds against Aedes aegypti populations resistant to the larvicide organophosphate temephos. In the present study, we evaluated the efficacy of the CSI triflumuron on Culex quinquefasciatus, Aedes albopictus and against several Ae. aegypti field populations. Methods: The efficacy of triflumuron, against Cx. quinquefasciatus and Ae. albopictus was evaluated with laboratory strains through dose-response assays. Additionaly, this CSI was tested against seven Ae. aegypti field populations exhibiting distinct resistance levels to both temephos and the pyrethroid deltamethrin. Aedes aegypti populations were exposed to both a dose that inhibits 99% of the adult emergence of mosquitoes from the susceptible reference strain, Rockefeller, (EI99 = 3.95 mu g/L) and the diagnostic dose (DD), corresponding to twice the EI99. Results: Our results indicate that triflumuron was effective in emergence inhibition (EI) of Cx. quinquefasciatus (EI50 = 5.28 mu g/L; EI90 = 12.47 mu g/L) and Ae. albopictus (EI50 = 1.59 mu g/L; EI90 = 2.63 mu g/L). Triflumuron was also effective against seven Ae. aegypti Brazilian populations resistant to both temephos and deltamethrin. Exposure of all the Ae. aegypti populations to the triflumuron EI99 of the susceptible reference strain, Rockefeller, resulted in complete inhibition of adult emergence, suggesting no cross-resistance among traditional insecticides and this CSI. However, a positive correlation between temephos resistance and tolerance to triflumuron was observed. Conclusion: The results suggest that triflumuron represents a potential tool for the control of disease vectors in public health. Nevertheless, they point to the need of constant monitoring of the susceptibility status of vector populations to CSIs. |
BibTeX: @article{Belinato, author = {Belinato, T. A. and Martins, A. J. and Lima, J. B. P. and Valle, D.}, title = {Effect of triflumuron, a chitin synthesis inhibitor, on Aedes aegypti, Aedes albopictus and Culex quinquefasciatus under laboratory conditions}, journal = {Parasites & Vectors}, doi = {10.1186/1756-3305-6-83} } |
| Brito LP, Linss JGB, Lima-Camara TN, Belinato TA, Peixoto AA, Lima JBP, Valle D and Martins AJ (2013), "Assessing the Effects of Aedes aegypti kdr Mutations on Pyrethroid Resistance and Its Fitness Cost", Plos One., April, 2013. Vol. 8(4), pp. e60878. Public Library Science. [DOI] |
| Abstract: Pyrethroids are the most used insecticide class worldwide. They target the voltage gated sodium channel (Na-V), inducing the knockdown effect. In Aedes aegypti, the main dengue vector, the AaNa(V) substitutions Val1016Ile and Phe1534Cys are the most important knockdown resistance (kdr) mutations. We evaluated the fitness cost of these kdr mutations related to distinct aspects of development and reproduction, in the absence of any other major resistance mechanism. To accomplish this, we initially set up 68 crosses with mosquitoes from a natural population. Allele-specific PCR revealed that one couple, the one originating the CIT-32 strain, had both parents homozygous for both kdr mutations. However, this pyrethroid resistant strain also presented high levels of detoxifying enzymes, which synergistically account for resistance, as revealed by biological and biochemical assays. Therefore, we carried out backcrosses between CIT-32 and Rockefeller (an insecticide susceptible strain) for eight generations in order to bring the kdr mutation into a susceptible genetic background. This new strain, named Rock-kdr, was highly resistant to pyrethroid and presented reduced alteration of detoxifying activity. Fitness of the Rock-kdr was then evaluated in comparison with Rockefeller. In this strain, larval development took longer, adults had an increased locomotor activity, fewer females laid eggs, and produced a lower number of eggs. Under an inter-strain competition scenario, the Rock-kdr larvae developed even slower. Moreover, when Rockefeller and Rock-kdr were reared together in population cage experiments during 15 generations in absence of insecticide, the mutant allele decreased in frequency. These results strongly suggest that the Ae. aegypti kdr mutations have a high fitness cost. Therefore, enhanced surveillance for resistance should be priority in localities where the kdr mutation is found before new adaptive alleles can be selected for diminishing the kdr deleterious effects. |
BibTeX: @article{Brito2013, author = {Brito, L. P. and Linss, J. G. B. and Lima-Camara, T. N. and Belinato, T. A. and Peixoto, A. A. and Lima, J. B. P. and Valle, D. and Martins, A. J.}, title = {Assessing the Effects of Aedes aegypti kdr Mutations on Pyrethroid Resistance and Its Fitness Cost}, journal = {Plos One}, publisher = {Public Library Science}, year = {2013}, volume = {8}, number = {4}, pages = {e60878}, doi = {10.1371/journal.pone.0060878} } |
| Chahad-Ehlers S, Gentile C, Lima JBP, Peixoto AA and Bruno RV (), "Analysis of cycle Gene Expression in Aedes aegypti Brains by In Situ Hybridization", Plos One. [DOI] |
| Abstract: Even though the blood-sucking mosquito Aedes aegypti is one of the most important disease vectors, relatively little is known about the molecular mechanisms underlying processes involved in the temporal pattern of its activity and host seeking behavior. In this study, we analyzed the expression of the cycle (cyc) gene, one of the core components of the circadian clock, in Ae. aegypti brains by in situ hybridization at two different time points in light-dark conditions and compared the results with those obtained using a quantitative PCR assay (qPCR). Within the brain, differential labeling was detected according to distinct areas empirically pre-defined. Six out of seven of these areas showed significantly higher staining at ZT3 (three hours after light-on) compared to ZT11 (one before light-off), which is consistent with the qPCR data. Predominant staining was observed in three of those areas which correspond to positions of the optical and antennal lobes, as well as the region where the neurons controlling activity rhythms are presumably localized. |
BibTeX: @article{Chahad-Ehlers, author = {Chahad-Ehlers, S. and Gentile, C. and Lima, J. B. P. and Peixoto, A. A. and Bruno, R. V.}, title = {Analysis of cycle Gene Expression in Aedes aegypti Brains by In Situ Hybridization}, journal = {Plos One}, doi = {10.1371/journal.pone.0052559} } |
| Daumas RP, Passos SRL, Oliveira RVC, Nogueira RMR, Georg I, Marzochi KBF and Brasil P (2013), "Clinical and laboratory features that discriminate dengue from other febrile illnesses: a diagnostic accuracy study in Rio de Janeiro, Brazil", Bmc Infectious Diseases., February, 2013. Vol. 13, pp. 77. Biomed Central Ltd. [DOI] |
| Abstract: Background: Dengue is an acute febrile illness caused by an arbovirus that is endemic in more than 100 countries. Early diagnosis and adequate management are critical to reduce mortality. This study aims to identify clinical and hematological features that could be useful to discriminate dengue from other febrile illnesses (OFI) up to the third day of disease. Methods: We conducted a sectional diagnostic study with patients aged 12 years or older who reported fever lasting up to three days, without any evident focus of infection, attending an outpatient clinic in the city of Rio de Janeiro, Brazil, between the years 2005 and 2008. Logistic regression analysis was used to identify symptoms, physical signs, and hematological features valid for dengue diagnosis. Receiver-operating characteristic (ROC) curve analyses were used to define the best cut-off and to compare the accuracy of generated models with the World Health Organization (WHO) criteria for probable dengue. Results: Based on serological tests and virus genome detection by polymerase chain reaction (PCR), 69 patients were classified as dengue and 73 as non-dengue. Among clinical features, conjunctival redness and history of rash were independent predictors of dengue infection. A model including clinical and laboratory features (conjunctival redness and leukocyte counts) achieved a sensitivity of 81% and specificity of 71% and showed greater accuracy than the WHO criteria for probable dengue. Conclusions: We constructed a predictive model for early dengue diagnosis that was moderately accurate and performed better than the current WHO criteria for suspected dengue. Validation of this model in larger samples and in other sites should be attempted before it can be applied in endemic areas. |
BibTeX: @article{Daumas2013, author = {Daumas, R. P. and Passos, S. R. L. and Oliveira, R. V. C. and Nogueira, R. M. R. and Georg, I. and Marzochi, K. B. F. and Brasil, P.}, title = {Clinical and laboratory features that discriminate dengue from other febrile illnesses: a diagnostic accuracy study in Rio de Janeiro, Brazil}, journal = {Bmc Infectious Diseases}, publisher = {Biomed Central Ltd}, year = {2013}, volume = {13}, pages = {77}, doi = {10.1186/1471-2334-13-77} } |
| De Castro MG, de Nogueira FB, Nogueira RMR, Lourenco-de-Oliveira R and dos Santos FB (2013), "Genetic variation in the 3 ' untranslated region of dengue virus serotype 3 strains isolated from mosquitoes and humans in Brazil", Virology Journal., January, 2013. Vol. 10, pp. 3. Biomed Central Ltd. [DOI] |
| Abstract: Background: Dengue, a mosquito-borne viral infection caused by one of the four dengue virus (DENV) serotypes (DENV-1 to 4), replicate alternately on the mosquito vector and human host and are responsible for infections throughout tropical and subtropical regions of the world. In Brazil, the disease has become a major public health problem and the introduction of DENV-3 in 2000 in Rio de Janeiro (RJ) was associated with severe dengue epidemics. The potential emergence of strains associated with severe disease highlights the need for the surveillance of DENV in human host and vectors. Methods: Aiming to contribute for DENV phylogenetic and vector-virus-human host studies, we sequenced the entire genome of one DENV-3 isolated from naturally infected Aedes aegypti from RJ in 2001 and characterized the 3' UTR from strains isolated from mosquitoes and humans. Mosquitoes were pooled and submitted to virus isolation in Ae. albopictus C6/36 cells and the infecting serotype was identified by immunofluorescence using type-specific monoclonal antibody. Sequence analysis was performed using BioEdit software, the multiple alignments were performed using CLUSTAL W and the phylogenetic analysis by MEGA 5, using the Neighbor-joining method. Secondary structure prediction was performed by using the MFOLD program. Results: Exclusive substitutions and a substitution leading to a stop codon on the NS5 gene were observed in the DENV-3 isolated from a naturally infected Ae. aegypti and fully sequenced. As an 8-nucleotides deletion was observed within the 11-nucleotides (nts) insertion on the variable region (VR) from the 3' UTR in this isolate, we further sequenced other DENV-3 from both mosquitoes and humans. The majority of DENV-3 from RJ analyzed were characterized by the 11-nts insertion in the VR of the 3' UTR, despite the observation of strains carrying the 8-nts deletion. The latter presented similar secondary structures, however not all strains presenting the 11-nts insertion were similar in the predicted secondary structure. Conclusions: The phylogeny based on the analysis of the complete genome and 3' UTR characterized the DENV-3 isolated from both vector and human host as belonging to Genotype III (GIII), despite the differences observed on the 3' UTR. Further studies are needed to address the role of those mutations in the transmission of the different viral populations and vector competence. |
BibTeX: @article{Castro2013, author = {De Castro, M. G. and de Nogueira, F. B. and Nogueira, R. M. R. and Lourenco-de-Oliveira, R. and dos Santos, F. B.}, title = {Genetic variation in the 3 ' untranslated region of dengue virus serotype 3 strains isolated from mosquitoes and humans in Brazil}, journal = {Virology Journal}, publisher = {Biomed Central Ltd}, year = {2013}, volume = {10}, pages = {3}, doi = {10.1186/1743-422X-10-3} } |
| Faria NRD, Nogueira RMR, de Filippis AMB, Simoes JBS, Nogueira FD, Lima MDQ and dos Santos FB (2013), "Twenty Years of DENV-2 Activity in Brazil: Molecular Characterization and Phylogeny of Strains Isolated from 1990 to 2010", Plos Neglected Tropical Diseases., March, 2013. Vol. 7(3), pp. e2095. Public Library Science. [DOI] |
| Abstract: In Brazil, dengue has been a major public health problem since its introduction in the 1980s. Phylogenetic studies constitute a valuable tool to monitor the introduction and spread of viruses as well as to predict the potential epidemiological consequences of such events. Aiming to perform the molecular characterization and phylogenetic analysis of DENV-2 during twenty years of viral activity in the country, viral strains isolated from patients presenting different disease manifestations (n = 34), representing six states of the country, from 1990 to 2010, were sequenced. Partial genome sequencing (genes C/prM/M/E) was performed in 25 DENV-2 strains and full-length genome sequencing (coding region) was performed in 9 strains. The percentage of similarity among the DENV-2 strains in this study and reference strains available in Genbank identified two groups epidemiologically distinct: one represented by strains isolated from 1990 to 2003 and one from strains isolated from 2007 to 2010. No consistent differences were observed on the E gene from strains isolated from cases with different clinical manifestations analyzed, suggesting that if the disease severity has a genetic origin, it is not only due to the differences observed on the E gene. The results obtained by the DENV-2 full-length genome sequencing did not point out consistent differences related to a more severe disease either. The analysis based on the partial and/or complete genome sequencing has characterized the Brazilian DENV-2 strains as belonging to the Southeast Asian genotype, however a distinction of two Lineages within this genotype has been identified. It was established that strains circulating prior DENV-2 emergence (1990-2003) belong to Southeast Asian genotype, Lineage I and strains isolated after DENV-2 emergence in 2007 belong to Southeast Asian genotype, Lineage II. Furthermore, all DENV-2 strains analyzed presented an asparagine (N) in E-390, previously identified as a probable genetic marker of virulence observed in DHF strains from Asian origin. The percentage of identity of the latter with the Dominican Republic strain isolated in 2001 combined to the percentage of divergence with the strains first introduced in the country in the 1990s suggests that those viruses did not evolve locally but were due to a new viral Lineage introduction in the country from the Caribbean. |
BibTeX: @article{Faria2013, author = {Faria, N. R. D. and Nogueira, R. M. R. and de Filippis, A. M. B. and Simoes, J. B. S. and Nogueira, F. D. and Lima, M. D. Q. and dos Santos, F. B.}, title = {Twenty Years of DENV-2 Activity in Brazil: Molecular Characterization and Phylogeny of Strains Isolated from 1990 to 2010}, journal = {Plos Neglected Tropical Diseases}, publisher = {Public Library Science}, year = {2013}, volume = {7}, number = {3}, pages = {e2095}, doi = {10.1371/journal.pntd.0002095} } |
| Gandini M, Gras C, Azeredo EL, Pinto LMdO, Smith N, Despres P, da Cunha RV, de Souza LJ, Kubelka CF and Herbeuval J-P (2013), "Dengue virus activates membrane TRAIL relocalization and IFN-α production by human plasmacytoid dendritic cells in vitro and in vivo.", PLoS Negl Trop Dis., Jun, 2013. Vol. 7(6), pp. e2257. [DOI] |
| Abstract: Dengue displays a broad spectrum of clinical manifestations that may vary from asymptomatic to severe and even fatal features. Plasma leakage/hemorrhages can be caused by a cytokine storm induced by monocytes and dendritic cells during dengue virus (DENV) replication. Plasmacytoid dendritic cells (pDCs) are innate immune cells and in response to virus exposure secrete IFN-α and express membrane TRAIL (mTRAIL). We aimed to characterize pDC activation in dengue patients and their function under DENV-2 stimulation in vitro. METHODS FINDINGS: Flow cytometry analysis (FCA) revealed that pDCs of mild dengue patients exhibit significantly higher frequencies of mTRAIL compared to severe cases or healthy controls. Plasma levels of IFN-α and soluble TRAIL are increased in mild compared to severe dengue patients, positively correlating with pDC activation. FCA experiments showed that in vitro exposure to DENV-2 induced mTRAIL expression on pDC. Furthermore, three dimension microscopy highlighted that TRAIL was relocalized from intracellular compartment to plasma membrane. Chloroquine treatment inhibited DENV-2-induced mTRAIL relocalization and IFN-α production by pDC. Endosomal viral degradation blockade by chloroquine allowed viral antigens detection inside pDCs. All those data are in favor of endocytosis pathway activation by DENV-2 in pDC. Coculture of pDC/DENV-2-infected monocytes revealed a dramatic decrease of antigen detection by FCA. This viral antigens reduction in monocytes was also observed after exogenous IFN-α treatment. Thus, pDC effect on viral load reduction was mainly dependent on IFN-α production.This investigation characterizes, during DENV-2 infection, activation of pDCs in vivo and their antiviral role in vitro. Thus, we propose TRAIL-expressing pDCs may have an important role in the outcome of disease. |
BibTeX: @article{Gandini2013, author = {Gandini, Mariana and Gras, Christophe and Azeredo, Elzinandes Leal and Pinto, Luzia Maria de Oliveira and Smith, Nikaïa and Despres, Philippe and da Cunha, Rivaldo Venâncio and de Souza, Luiz José and Kubelka, Claire Fernandes and Herbeuval, Jean-Philippe}, title = {Dengue virus activates membrane TRAIL relocalization and IFN-α production by human plasmacytoid dendritic cells in vitro and in vivo.}, journal = {PLoS Negl Trop Dis}, year = {2013}, volume = {7}, number = {6}, pages = {e2257}, url = {http://dx.doi.org/10.1371/journal.pntd.0002257}, doi = {10.1371/journal.pntd.0002257} } |
| Gibson G, Souza-Santos R, Brasil P, Pacheco AG, Cruz OG, Honorio NA, Kubelka C and Carvalho MS (2013), "From primary care to hospitalization: clinical warning signs of severe dengue fever in children and adolescents during an outbreak in Rio de Janeiro, Brazil", Cadernos De Saude Publica., January, 2013. Vol. 29(1), pp. 82-90. Cadernos Saude Publica. [DOI] |
| Abstract: We analyzed factors associated with severe cases of dengue in children and adolescents hospitalized during the 2007/2008 epidemic in Rio de Janeiro, Brazil. This is a retrospective case-control study that covers 88 cases of severe dengue in patients admitted to four tertiary care children's hospitals. Controls consisted of 22 children with non-severe dengue living in the same neighbor-hood as the patients with severe dengue. Differences in prevalence of the clinical signs - abdominal pain, breathing difficulty, drowsiness or irritability - emerged on the third day after the onset of symptoms, in the febrile stage. Cases and controls received first medical care at the same clinical stage of disease. However, hospital admission of severe cases occurred later, on average between the third and fourth day after the onset of the disease. Early discharge of patients with fever whose condition could have progressed to severe dengue may have been a consequence of the type of medical assistance provided by primary care units, suggesting deficiencies both in the use of the risk classification protocol and patient triage. |
BibTeX: @article{Gibson2013, author = {Gibson, G. and Souza-Santos, R. and Brasil, P. and Pacheco, A. G. and Cruz, O. G. and Honorio, N. A. and Kubelka, C. and Carvalho, M. S.}, title = {From primary care to hospitalization: clinical warning signs of severe dengue fever in children and adolescents during an outbreak in Rio de Janeiro, Brazil}, journal = {Cadernos De Saude Publica}, publisher = {Cadernos Saude Publica}, year = {2013}, volume = {29}, number = {1}, pages = {82--90}, doi = {10.1590/S0102-311X2013000100010} } |
| Gras C, Smith N, Sengmanivong L, Gandini M, Kubelka CF and Herbeuval JP (), "TRAIL protein localization in human primary T cells by 3D microscopy using 3D interactive surface plot: A new method to visualize plasma membrane", Journal of Immunological Methods. [DOI] |
| Abstract: The apoptotic ligand TNF-related apoptosis ligand (TRAIL) is expressed on the membrane of immune cells during HIV infection. The intracellular stockade of TRAIL in human primary CD4(+) T cells is not known. Here we investigated whether primary CD4(+) T cells expressed TRAIL in their intracellular compartment and whether TRAIL is relocalized on the plasma membrane under HIV activation. We found that TRAIL protein was stocked in intracellular compartment in non activated CD4(+) T cells and that the total level of TRAIL protein was not increased under HIV-1 stimulation. However, TRAIL was massively relocalized on plasma membrane when cells were cultured with HIV. Using three dimensional (3D) microscopy we localized TRAIL protein in human T cells and developed a new method to visualize plasma membrane without the need of a membrane marker. This method used the 3D interactive surface plot and bright light acquired images. (C) 2012 Elsevier B.V. All rights reserved. |
BibTeX: @article{Gras, author = {Gras, C. and Smith, N. and Sengmanivong, L. and Gandini, M. and Kubelka, C. F. and Herbeuval, J. P.}, title = {TRAIL protein localization in human primary T cells by 3D microscopy using 3D interactive surface plot: A new method to visualize plasma membrane}, journal = {Journal of Immunological Methods}, doi = {10.1016/j.jim.2012.10.008} } |
| Henriques HR, Rampazo EV, Gonçalves AJS, Vicentin ECM, Amorim JH, Panatieri RH, Amorim KNS, Yamamoto MM, Ferreira LCS, Alves AMB and Boscardin SB (2013), "Targeting the non-structural protein 1 from dengue virus to a dendritic cell population confers protective immunity to lethal virus challenge.", PLoS Negl Trop Dis., Jul, 2013. Vol. 7(7), pp. e2330. [DOI] |
| Abstract: Dengue is the most prevalent arboviral infection, affecting millions of people every year. Attempts to control such infection are being made, and the development of a vaccine is a World Health Organization priority. Among the proteins being tested as vaccine candidates in preclinical settings is the non-structural protein 1 (NS1). In the present study, we tested the immune responses generated by targeting the NS1 protein to two different dendritic cell populations. Dendritic cells (DCs) are important antigen presenting cells, and targeting proteins to maturing DCs has proved to be an efficient means of immunization. Antigen targeting is accomplished by the use of a monoclonal antibody (mAb) directed against a DC cell surface receptor fused to the protein of interest. We used two mAbs (αDEC205 and αDCIR2) to target two distinct DC populations, expressing either DEC205 or DCIR2 endocytic receptors, respectively, in mice. The fusion mAbs were successfully produced, bound to their respective receptors, and were used to immunize BALB/c mice in the presence of polyriboinosinic: polyribocytidylic acid (poly (I:C)), as a DC maturation stimulus. We observed induction of strong anti-NS1 antibody responses and similar antigen binding affinity irrespectively of the DC population targeted. Nevertheless, the IgG1/IgG2a ratios were different between mouse groups immunized with αDEC-NS1 and αDCIR2-NS1 mAbs. When we tested the induction of cellular immune responses, the number of IFN-γ producing cells was higher in αDEC-NS1 immunized animals. In addition, mice immunized with the αDEC-NS1 mAb were significantly protected from a lethal intracranial challenge with the DENV2 NGC strain when compared to mice immunized with αDCIR2-NS1 mAb. Protection was partially mediated by CD4(+) and CD8(+) T cells as depletion of these populations reduced both survival and morbidity signs. We conclude that targeting the NS1 protein to the DEC205(+) DC population with poly (I:C) opens perspectives for dengue vaccine development. |
BibTeX: @article{Henriques2013, author = {Henriques, Hugo R. and Rampazo, Eline V. and Gonçalves, Antonio J S. and Vicentin, Elaine C M. and Amorim, Jaime H. and Panatieri, Raquel H. and Amorim, Kelly N S. and Yamamoto, Marcio M. and Ferreira, Luís C S. and Alves, Ada M B. and Boscardin, Silvia B.}, title = {Targeting the non-structural protein 1 from dengue virus to a dendritic cell population confers protective immunity to lethal virus challenge.}, journal = {PLoS Negl Trop Dis}, year = {2013}, volume = {7}, number = {7}, pages = {e2330}, url = {http://dx.doi.org/10.1371/journal.pntd.0002330}, doi = {10.1371/journal.pntd.0002330} } |
| Hottz ED, Oliveira MF, Nunes PCG, Nogueira RMR, Valls-De-Souza R, Da Poian AT, Weyrich AS, Zimmerman GA, Bozza PT and Bozza FA (2013), "Dengue induces platelet activation, mitochondrial dysfunction and cell death through mechanisms that involve DC-SIGN and caspases", Journal of Thrombosis and Haemostasis., May, 2013. Vol. 11(5), pp. 951-962. Wiley-blackwell. [DOI] |
| Abstract: Background Worldwide, dengue is the most prevalent human arbovirus disease. Dengue infection may cause a range of clinical manifestations from self-limiting febrile illness through to a life-threatening syndrome accompanied by both bleeding and shock. Thrombocytopenia is frequently observed in mild and severe disease; however, the mechanisms involved in DENV-induced platelet activation and thrombocytopenia are incompletely understood. Patients and methods Freshly isolated platelets from patients with dengue were evaluated for markers of activation, mitochondrial alteration and activation of cell death pathways. In parallel, we examined direct DENV-induced activation and apoptosis of platelets obtained from healthy subjects. Results We found that platelets from DENV-infected patients exhibited increased activation by comparison to control subjects. Moreover, platelets from DENV-infected patients exhibited classic signs of the intrinsic pathway of apoptosis that include increased surface phosphatidylserine exposure, mitochondrial depolarization and activation of caspase-9 and -3. Indeed, thrombocytopenia was shown to strongly associate with enhanced platelet activation and cell death in DENV-infected patients. Platelet activation, mitochondrial dysfunction and caspase-dependent phosphatidylserine exposure on platelets were also observed when platelets from healthy subjects were directly exposed to DENV in vitro. DENV-induced platelet activation was shown to occur through mechanisms largely dependent on DC-SIGN. Conclusions Together our results demonstrate that platelets from patients with dengue present signs of activation, mitochondrial dysfunction and activation of the apoptosis caspase cascade, which may contribute to the development of thrombocytopenia in patients with dengue. Our results also suggest the involvement of DC-SIGN as a critical receptor in DENV-dependent platelet activation. |
BibTeX: @article{Hottz2013, author = {Hottz, E. D. and Oliveira, M. F. and Nunes, P. C. G. and Nogueira, R. M. R. and Valls-De-Souza, R. and Da Poian, A. T. and Weyrich, A. S. and Zimmerman, G. A. and Bozza, P. T. and Bozza, F. A.}, title = {Dengue induces platelet activation, mitochondrial dysfunction and cell death through mechanisms that involve DC-SIGN and caspases}, journal = {Journal of Thrombosis and Haemostasis}, publisher = {Wiley-blackwell}, year = {2013}, volume = {11}, number = {5}, pages = {951--962}, doi = {10.1111/jth.12178} } |
| Longo CL, Brasil P, Espindola OD, Leite ACCB, Nogueira RMR, Lupi O and Neves ED (2013), "Dengue fever and human T-cell lymphotropic virus type 1 infection", International Journal of Infectious Diseases., July, 2013. Vol. 17(7), pp. E562-E564. Elsevier Sci Ltd. [DOI] |
| Abstract: Globalization has increased both the number of emergent diseases and the diversity of co-infections, which could in turn mutually influence the pathogenesis of well-known infectious diseases. Here, we report the first series of chronic human T-cell lymphotropic virus type 1 (HTLV-1) patients co-infected with the dengue fever virus. As both of these diseases are immuno-mediated, we anticipated interference in the development of both diseases, with atypical clinical and laboratory parameter results. All the patients had classic dengue fever, and the main outstanding abnormality was leukopenia associated with lymphopenia. Although a mutual influence was expected, dengue fever did not affect the clinical course of HTLV-1 infection, and HTLV-1 proviral loads revealed unpredictable patterns of change. (C) 2013 International Society for Infectious Diseases. Published by Elsevier Ltd. All rights reserved. |
BibTeX: @article{Longo2013, author = {Longo, C. L. and Brasil, P. and Espindola, O. D. and Leite, A. C. C. B. and Nogueira, R. M. R. and Lupi, O. and Neves, E. D.}, title = {Dengue fever and human T-cell lymphotropic virus type 1 infection}, journal = {International Journal of Infectious Diseases}, publisher = {Elsevier Sci Ltd}, year = {2013}, volume = {17}, number = {7}, pages = {E562--E564}, doi = {10.1016/j.ijid.2013.01.014} } |
| Macedo GA, de Araujo JMG, Schatzmayra HG, Costa FAC, de Filippis AMB, dos Santos FB and Nogueira RM (2013), "Virological surveillance for early warning of dengue epidemics in the State of Rio de Janeiro, Brazil", Transactions of the Royal Society of Tropical Medicine and Hygiene., March, 2013. Vol. 107(3), pp. 141-146. Oxford Univ Press. [DOI] |
| Abstract: Background: The state of Rio de Janeiro has been important since 1986 as a portal for the introduction of dengue virus (DENV) into Brazil and dissemination of the virus throughout the country. This study describes an active surveillance of DENV in the state of Rio de Janeiro from 2004 to 2008. Method: A total of 14 408 samples from patients suspected to be infected with DENV were tested by virus isolation, and nested reverse transcriptase (RT)-PCR assay or anti-DENV dengue IgM antibody capture ELISA (MAC-ELISA), or both. Results: By the use of these different methods, a total of 2324(16.1%) cases were confirmed as dengue infection. The study covers an inter-epidemic period (2004-2005), the DENV-3 circulation in 2006, the re-emergence of DENV-2 in 2007 and the severe epidemic caused by DENV-2 in the summer of 2008. During the period, 69 dengue fatal cases were reported, 14 (20.2%) deaths being attributable to DENV-3 and 55 (79.7%) to DENV-2. Conclusion: Our results emphasize the role of the laboratory in the early detection of dengue virus transmission and provide information on the dynamics of DENV introduction and spread, important for the assessment of intervention strategies. |
BibTeX: @article{Macedo2013, author = {Macedo, G. A. and de Araujo, J. M. G. and Schatzmayra, H. G. and Costa, F. A. C. and de Filippis, A. M. B. and dos Santos, F. B. and Nogueira, R. M.}, title = {Virological surveillance for early warning of dengue epidemics in the State of Rio de Janeiro, Brazil}, journal = {Transactions of the Royal Society of Tropical Medicine and Hygiene}, publisher = {Oxford Univ Press}, year = {2013}, volume = {107}, number = {3}, pages = {141--146}, doi = {10.1093/trstmh/trs091} } |
| Maciel-de-Freitas R, Sylvestre G, Gandini M and Koella JC (2013), "The Influence of Dengue Virus Serotype-2 Infection on Aedes aegypti (Diptera: Culicidae) Motivation and Avidity to Blood Feed", Plos One., June, 2013. Vol. 8(6), pp. e65252. Public Library Science. [DOI] |
| Abstract: Background: Dengue virus (DENV) is transmitted by Aedes aegypti, a species that lives in close association with human dwellings. The behavior of DENV-infected mosquitoes needs further investigation, especially regarding the potential influence of DENV on mosquito biting motivation and avidity. Methodology/Principal findings: We orally challenged 4-5 day-old Ae. aegypti females with a low passage DENV serotype 2 (DENV-2) to test whether the virus influences motivation to feed (the likelihood that a mosquito obtains a blood-meal and the size of its blood meal) and avidity (the likelihood to re-feed after an interrupted first blood-meal). To assay motivation, we offered mosquitoes an anesthetized mouse for 2, 3, 4 or 5 minutes 7 or 14 days after the initial blood meals and measured the time they started feeding. 60.5% of the unexposed mosquitoes fed on the mouse, but only 40.5% of the positive ones did. Exposed but negative mosquitoes behaved similarly to unexposed ones (55.0% feeding). Thus DENV-2 infection decreased the mosquitoes' motivation to feed. To assay avidity, we offered the same mosquitoes a mouse two hours after the first round of feeding, and we measured the time at which they started probing. The exposed (positive or negative) mosquitoes were more likely to re-feed than the unexposed ones and, in particular, the size of the previous blood-meal that kept mosquitoes from re-feeding was larger in the exposed than in the unexposed mosquitoes. Thus, DENV-2 infection increased mosquito avidity. Conclusions/Significance: DENV-2 significantly decreased the mosquitoes' motivation to feed, but increased their avidity (even after taking account the amount of blood previously imbibed). As these are important components of transmission, we expect that the changes of the blood-feeding behaviour impact the vectorial capacity Ae. aegypti for dengue. |
BibTeX: @article{Maciel-de-Freitas2013, author = {Maciel-de-Freitas, R. and Sylvestre, G. and Gandini, M. and Koella, J. C.}, title = {The Influence of Dengue Virus Serotype-2 Infection on Aedes aegypti (Diptera: Culicidae) Motivation and Avidity to Blood Feed}, journal = {Plos One}, publisher = {Public Library Science}, year = {2013}, volume = {8}, number = {6}, pages = {e65252}, doi = {10.1371/journal.pone.0065252} } |
| Maldaner FR, Aragão FJL, dos Santos FB, Franco OL, da Rocha Queiroz Lima M, de Oliveira Resende R, Vasques RM and Nagata T (2013), "Dengue virus tetra-epitope peptide expressed in lettuce chloroplasts for potential use in dengue diagnosis.", Appl Microbiol Biotechnol., Jul, 2013. Vol. 97(13), pp. 5721-5729. [DOI] |
| Abstract: Dengue virus causes about 100 million cases of dengue disease per year in the world. Laboratory diagnosis is done mainly by serological techniques, which in many cases use crude virus extracts that may cause cross-reactions to other flaviviruses. These undesirable cross-reactions can be reduced or eliminated by using recombinant proteins based on restricted epitopes. Aiming to decrease flaviviral cross-reactions and non-specific interactions in dengue serological assays, a plant expression system was chosen for recombinant antigen production as a reliable and inexpensive dengue diagnostic tool. In the present report, the lettuce plastid transformation system was applied to achieve efficient and stable tetra-epitope peptide antigen production, and its reactivity was evaluated. For this purpose, one putative epitope at positions 34 to 57 of E protein within the junction site of domains I and II of dengue virus (DENV) 1 to 4 serotypes linked by glycine linkers was expressed in lettuce chloroplasts. The potential immunoreactivity for the four DENV serotypes was evaluated using sera from patients of positive and negative dengue cases. Results indicated an overall sensitivity of 71.7% and specificity of 100 No cross-reactions with the sera of yellow fever-positive or healthy individuals vaccinated against yellow fever were observed. This novel approach may provide an alternative system for the large-scale production of dengue recombinant antigens useful for serodiagnosis. |
BibTeX: @article{Maldaner2013, author = {Maldaner, Franciele Roberta and Aragão, Francisco José Lima and dos Santos, Flávia Barreto and Franco, Octavio Luiz and da Rocha Queiroz Lima, Monique and de Oliveira Resende, Renato and Vasques, Raquel Medeiros and Nagata, Tatsuya}, title = {Dengue virus tetra-epitope peptide expressed in lettuce chloroplasts for potential use in dengue diagnosis.}, journal = {Appl Microbiol Biotechnol}, year = {2013}, volume = {97}, number = {13}, pages = {5721--5729}, url = {http://dx.doi.org/10.1007/s00253-013-4918-6}, doi = {10.1007/s00253-013-4918-6} } |
| Martins MA, Bonaldo MC, Rudersdorf RA, Piaskowski SM, Rakasz EG, Weisgrau KL, Furlott JR, Eernisse CM, de Santana MGV, Hidalgo B, Friedrich TC, Chiuchiolo MJ, Parks CL, Wilson NA, Allison DB, Galler R and Watkins DI (2013), "Immunogenicity of Seven New Recombinant Yellow Fever Viruses 17D Expressing Fragments of SIVmac239 Gag, Nef, and Vif in Indian Rhesus Macaques", Plos One., January, 2013. Vol. 8(1), pp. e54434. Public Library Science. [DOI] |
| Abstract: An effective vaccine remains the best solution to stop the spread of human immunodeficiency virus (HIV). Cellular immune responses have been repeatedly associated with control of viral replication and thus may be an important element of the immune response that must be evoked by an efficacious vaccine. Recombinant viral vectors can induce potent T-cell responses. Although several viral vectors have been developed to deliver HIV genes, only a few have been advanced for clinical trials. The live-attenuated yellow fever vaccine virus 17D (YF17D) has many properties that make it an attractive vector for AIDS vaccine regimens. YF17D is well tolerated in humans and vaccination induces robust T-cell responses that persist for years. Additionally, methods to manipulate the YF17D genome have been established, enabling the generation of recombinant (r)YF17D vectors carrying genes from unrelated pathogens. Here, we report the generation of seven new rYF17D viruses expressing fragments of simian immunodeficiency virus (SIV)mac239 Gag, Nef, and Vif. Studies in Indian rhesus macaques demonstrated that these live-attenuated vectors replicated in vivo, but only elicited low levels of SIV-specific cellular responses. Boosting with recombinant Adenovirus type-5 (rAd5) vectors resulted in robust expansion of SIV-specific CD8(+) T-cell responses, particularly those targeting Vif. Priming with rYF17D also increased the frequency of CD4(+) cellular responses in rYF17D/ rAd5-immunized macaques compared to animals that received rAd5 only. The effect of the rYF17D prime on the breadth of SIV-specific T-cell responses was limited and we also found evidence that some rYF17D vectors were more effective than others at priming SIV-specific T-cell responses. Together, our data suggest that YF17D - a clinically relevant vaccine vector - can be used to prime AIDS virus-specific T-cell responses in heterologous prime boost regimens. However, it will be important to optimize rYF17D-based vaccine regimens to ensure maximum delivery of all immunogens in a multivalent vaccine. |
BibTeX: @article{Martins2013, author = {Martins, M. A. and Bonaldo, M. C. and Rudersdorf, R. A. and Piaskowski, S. M. and Rakasz, E. G. and Weisgrau, K. L. and Furlott, J. R. and Eernisse, C. M. and de Santana, M. G. V. and Hidalgo, B. and Friedrich, T. C. and Chiuchiolo, M. J. and Parks, C. L. and Wilson, N. A. and Allison, D. B. and Galler, R. and Watkins, D. I.}, title = {Immunogenicity of Seven New Recombinant Yellow Fever Viruses 17D Expressing Fragments of SIVmac239 Gag, Nef, and Vif in Indian Rhesus Macaques}, journal = {Plos One}, publisher = {Public Library Science}, year = {2013}, volume = {8}, number = {1}, pages = {e54434}, doi = {10.1371/journal.pone.0054434} } |
| Martins RM, Maia MdLS, Farias RHG, Camacho LAB, Freire MS, Galler R, Yamamura AMY, Almeida LFC, Lima SMB, Nogueira RMR, Sá GRS, Hokama DA, de Carvalho R, Freire RAV, Pereira Filho E, Leal MdLF and Homma A (2013), "17DD yellow fever vaccine: a double blind, randomized clinical trial of immunogenicity and safety on a dose-response study.", Hum Vaccin Immunother., Apr, 2013. Vol. 9(4), pp. 879-888. [DOI] |
| Abstract: To verify if the Bio-Manguinhos 17DD yellow fever vaccine (17DD-YFV) used in lower doses is as immunogenic and safe as the current formulation.Doses from 27,476 IU to 587 IU induced similar seroconversion rates and neutralizing antibodies geometric mean titers (GMTs). Immunity of those who seroconverted to YF was maintained for 10 mo. Reactogenicity was low for all groups.Young and healthy adult males (n = 900) were recruited and randomized into 6 groups, to receive de-escalating doses of 17DD-YFV, from 27,476 IU to 31 IU. Blood samples were collected before vaccination (for neutralization tests to yellow fever, serology for dengue and clinical chemistry), 3 to 7 d after vaccination (for viremia and clinical chemistry) and 30 d after vaccination (for new yellow fever serology and clinical chemistry). Adverse events diaries were filled out by volunteers during 10 d after vaccination. Volunteers were retested for yellow fever and dengue antibodies 10 mo later. Seropositivity for dengue was found in 87.6% of volunteers before vaccination, but this had no significant influence on conclusions.In young healthy adults Bio-Manguinhos/Fiocruz yellow fever vaccine can be used in much lower doses than usual. INTERNATIONAL REGISTER: ISRCTN 38082350. |
BibTeX: @article{Martins2013a, author = {Martins, Reinaldo M. and Maia, Maria de Lourdes S. and Farias, Roberto Henrique G. and Camacho, Luiz Antonio B. and Freire, Marcos S. and Galler, Ricardo and Yamamura, Anna Maya Yoshida and Almeida, Luiz Fernando C. and Lima, Sheila Maria B. and Nogueira, Rita Maria R. and Sá, Gloria Regina S. and Hokama, Darcy A. and de Carvalho, Ricardo and Freire, Ricardo Aguiar V. and Pereira Filho, Edson and Leal, Maria da Luz Fernandes and Homma, Akira}, title = {17DD yellow fever vaccine: a double blind, randomized clinical trial of immunogenicity and safety on a dose-response study.}, journal = {Hum Vaccin Immunother}, year = {2013}, volume = {9}, number = {4}, pages = {879--888}, url = {http://dx.doi.org/10.4161/hv.22982}, doi = {10.4161/hv.22982} } |
| Nogueira RT, Nogueira AR, Pereira MCS, Rodrigues MM, Neves PCD, Galler R and Bonaldo MC (2013), "Recombinant Yellow Fever Viruses Elicit CD8(+) T Cell Responses and Protective Immunity against Trypanosoma cruzi", Plos One., March, 2013. Vol. 8(3), pp. e59347. Public Library Science. [DOI] |
| Abstract: Chagas' disease is a major public health problem affecting nearly 10 million in Latin America. Despite several experimental vaccines have shown to be immunogenic and protective in mouse models, there is not a current vaccine being licensed for humans or in clinical trial against T. cruzi infection. Towards this goal, we used the backbone of Yellow Fever (YF) 17D virus, one of the most effective and well-established human vaccines, to express an immunogenic fragment derived from T. cruzi Amastigote Surface Protein 2 (ASP-2). The cDNA sequence of an ASP-2 fragment was inserted between E and NS1 genes of YF 17D virus through the construction of a recombinant heterologous cassette. The replication ability and genetic stability of recombinant YF virus (YF17D/ENS1/Tc) was confirmed for at least six passages in Vero cells. Immunogenicity studies showed that YF17D/ENS1/Tc virus elicited neutralizing antibodies and gamma interferon (IFN-gamma) producing-cells against the YF virus. Also, it was able to prime a CD8(+) T cell directed against the transgenic T. cruzi epitope (TEWETGQI) which expanded significantly as measured by T cell-specific production of IFN-gamma before and after T. cruzi challenge. However, most important for the purposes of vaccine development was the fact that a more efficient protective response could be seen in mice challenged after vaccination with the YF viral formulation consisting of YF17D/ENS1/Tc and a YF17D recombinant virus expressing the TEWETGQI epitope at the NS2B-3 junction. The superior protective immunity observed might be due to an earlier priming of epitope-specific IFN-gamma-producing T CD8(+) cells induced by vaccination with this viral formulation. Our results suggest that the use of viral formulations consisting of a mixture of recombinant YF 17D viruses may be a promising strategy to elicit protective immune responses against pathogens, in general. |
BibTeX: @article{Nogueira2013, author = {Nogueira, R. T. and Nogueira, A. R. and Pereira, M. C. S. and Rodrigues, M. M. and Neves, P. C. D. and Galler, R. and Bonaldo, M. C.}, title = {Recombinant Yellow Fever Viruses Elicit CD8(+) T Cell Responses and Protective Immunity against Trypanosoma cruzi}, journal = {Plos One}, publisher = {Public Library Science}, year = {2013}, volume = {8}, number = {3}, pages = {e59347}, doi = {10.1371/journal.pone.0059347} } |
| Pauvolid-Correa A, Kenney JL, Couto-Lima D, Campos ZMS, Schatzmayr HG, Nogueira RMR, Brault AC and Komar N (2013), "Ilheus Virus Isolation in the Pantanal, West-Central Brazil", Plos Neglected Tropical Diseases., July, 2013. Vol. 7(7), pp. e2318. Public Library Science. [DOI] |
| Abstract: The wetlands of the Brazilian Pantanal host large concentrations of diverse wildlife species and hematophagous arthropods, conditions that favor the circulation of zoonotic arboviruses. A recent study from the Nhecolandia sub-region of Pantanal reported serological evidence of various flaviviruses, including West Nile virus and Ilheus virus (ILHV). According to the age of seropositive horses, at least three flaviviruses, including ILHV, circulated in the Brazilian Pantanal between 2005 and 2009. To extend this study, we collected 3,234 adult mosquitoes of 16 species during 2009 and 2010 in the same sub-region. Mosquito pool homogenates were assayed for infectious virus on C6/36 and Vero cell monolayers and also tested for flaviviral RNA by a group-specific real-time RT-PCR. One pool containing 50 non-engorged female specimens of Aedes scapularis tested positive for ILHV by culture and for ILHV RNA by real-time RT-PCR, indicating a minimum infection rate of 2.5 per 1000. Full-length genomic sequence exhibited 95% identity to the only full genome sequence available for ILHV. The present data confirm the circulation of ILHV in the Brazilian Pantanal. |
BibTeX: @article{Pauvolid-Correa2013, author = {Pauvolid-Correa, A. and Kenney, J. L. and Couto-Lima, D. and Campos, Z. M. S. and Schatzmayr, H. G. and Nogueira, R. M. R. and Brault, A. C. and Komar, N.}, title = {Ilheus Virus Isolation in the Pantanal, West-Central Brazil}, journal = {Plos Neglected Tropical Diseases}, publisher = {Public Library Science}, year = {2013}, volume = {7}, number = {7}, pages = {e2318}, doi = {10.1371/journal.pntd.0002318} } |
| Peres RC, Rego R and Maciel-de-Freitas R (2013), "The use of the Premise Condition Index (PCI) to provide guidelines for Aedes aegypti surveys", Journal of Vector Ecology., June, 2013. Vol. 38(1), pp. 190-192. Soc Vector Ecology. [DOI] |
BibTeX: @article{Peres2013, author = {Peres, R. C. and Rego, R. and Maciel-de-Freitas, R.}, title = {The use of the Premise Condition Index (PCI) to provide guidelines for Aedes aegypti surveys}, journal = {Journal of Vector Ecology}, publisher = {Soc Vector Ecology}, year = {2013}, volume = {38}, number = {1}, pages = {190--192}, doi = {10.1111/j.1948-7134.2013.12027.x} } |
| Ribeiro CF, Lopes VGS, Brasil P, Coelho J, Muniz AG and Nogueira RMR (2013), "Perinatal transmission of dengue: a report of 7 cases.", J Pediatr., Nov, 2013. Vol. 163(5), pp. 1514-1516. [DOI] |
| Abstract: Perinatal transmission of dengue virus was confirmed by the evidence of virus in fetal tissue, newborn serum, and placenta of pregnant women. Abortion, several different clinical findings, and placental inflammatory findings were documented. No association was seen between severity of maternal dengue and disease of the newborn. |
BibTeX: @article{Ribeiro2013, author = {Ribeiro, Christiane Fernandes and Lopes, Vânia Glória Silami and Brasil, Patrícia and Coelho, Janice and Muniz, Adriana Gouveia and Nogueira, Rita Maria Ribeiro}, title = {Perinatal transmission of dengue: a report of 7 cases.}, journal = {J Pediatr}, year = {2013}, volume = {163}, number = {5}, pages = {1514--1516}, url = {http://dx.doi.org/10.1016/j.jpeds.2013.06.040}, doi = {10.1016/j.jpeds.2013.06.040} } |
| Saboia-Vahia L, Borges-Veloso A, Mesquita-Rodrigues C, Cuervo P, Dias-Lopes G, Britto C, Silva APD and De Jesus JB (2013), "Trypsin-like serine peptidase profiles in the egg, larval, and pupal stages of Aedes albopictus", Parasites & Vectors., February, 2013. Vol. 6, pp. 50. Biomed Central Ltd. [DOI] |
| Abstract: Aedes albopictus, a ubiquitous mosquito, is one of the main vectors of dengue and yellow fever, representing an important threat to public health worldwide. Peptidases play key roles in processes such as digestion, oogenesis, and metamorphosis of insects. However, most of the information on the proteolytic enzymes of mosquitoes is derived from insects in the adult stages and is often directed towards the understanding of blood digestion. The aim of this study was to investigate the expression of active peptidases from the preimaginal stages of Ae. albopictus. Methods: Ae. albopictus eggs, larvae, and pupae were analyzed using zymography with susbtrate-SDS-PAGE. The pH, temperature and peptidase inhibitor sensitivity was evaluated. In addition, the proteolytic activities of larval instars were assayed using the fluorogenic substrate Z-Phe-Arg-AMC. Results: The proteolytic profile of the larval stage was composed of 8 bands ranging from 17 to 130 kDa. These enzymes displayed activity in a broad range of pH values, from 5.5 to 10.0. The enzymatic profile of the eggs was similar to that of the larvae, although the proteolytic bands of the eggs showed lower intensities. The pupal stage showed a complex proteolytic pattern, with at least 6 bands with apparent molecular masses ranging from 30 to 150 kDa and optimal activity at pH 7.5. Peptidases from larval instars were active from 10 degrees C to 60 degrees C, with optimal activity at temperatures between 37 degrees C and 50 degrees C. The proteolytic profile of both the larval and pupal stages was inhibited by phenyl-methyl sulfonyl-fluoride (PMSF) and Na-Tosyl L-lysine chloromethyl ketone hydrochloride (TLCK), indicating that the main peptidases expressed during these developmental stages are trypsin-like serine peptidases. Conclusion: The preimaginal stages of Ae. albopictus exhibited a complex profile of trypsin-like serine peptidase activities. A comparative analysis of the active peptidase profiles revealed differential expression of trypsin-like isoforms among the preimaginal stages, suggesting that some of these enzymes are stage specific. Additionally, a comparison of the peptidase expression between larvae from eggs collected in the natural environment and larvae obtained from the eggs of female mosquitoes maintained in colonies for a long period of time demonstrated that the proteolytic profile is invariable under such conditions. |
BibTeX: @article{Saboia-Vahia2013, author = {Saboia-Vahia, L. and Borges-Veloso, A. and Mesquita-Rodrigues, C. and Cuervo, P. and Dias-Lopes, G. and Britto, C. and Silva, A. P. D. and De Jesus, J. B.}, title = {Trypsin-like serine peptidase profiles in the egg, larval, and pupal stages of Aedes albopictus}, journal = {Parasites & Vectors}, publisher = {Biomed Central Ltd}, year = {2013}, volume = {6}, pages = {50}, doi = {10.1186/1756-3305-6-50} } |
| Sylvestre G, Gandini M and Maciel-de-Freitas R (2013), "Age-Dependent Effects of Oral Infection with Dengue Virus on Aedes aegypti (Diptera: Culicidae) Feeding Behavior, Survival, Oviposition Success and Fecundity", Plos One., March, 2013. Vol. 8(3), pp. e59933. Public Library Science. [DOI] |
| Abstract: Background: Aedes aegypti is the main vector of dengue, a disease that is increasing its geographical range as well as incidence rates. Despite its public health importance, the effect of dengue virus (DENV) on some mosquito traits remains unknown. Here, we investigated the impact of DENV-2 infection on the feeding behavior, survival, oviposition success and fecundity of Ae. aegypti females. Methods/Principal Findings: After orally-challenging Ae. aegypti females with a DENV-2 strain using a membrane feeder, we monitored the feeding behavior, survival, oviposition success and fecundity throughout the mosquito lifespan. We observed an age-dependent cost of DENV infection on mosquito feeding behavior and fecundity. Infected individuals took more time to ingest blood from anesthetized mice in the 2nd and 3rd weeks post-infection, and also longer overall blood-feeding times in the 3rd week post-infection, when females were around 20 days old. Often, infected Ae. aegypti females did not lay eggs and when they were laid, smaller number of eggs were laid compared to uninfected controls. A reduction in the number of eggs laid per female was evident starting on the 3rd week post-infection. DENV-2 negatively affected mosquito lifespan, since overall the longevity of infected females was halved compared to that of the uninfected control group. Conclusions: The DENV-2 strain tested significantly affected Ae. aegypti traits directly correlated with vectorial capacity or mosquito population density, such as feeding behavior, survival, fecundity and oviposition success. Infected mosquitoes spent more time ingesting blood, had reduced lifespan, laid eggs less frequently, and when they did lay eggs, the clutches were smaller than uninfected mosquitoes. |
BibTeX: @article{Sylvestre2013, author = {Sylvestre, G. and Gandini, M. and Maciel-de-Freitas, R.}, title = {Age-Dependent Effects of Oral Infection with Dengue Virus on Aedes aegypti (Diptera: Culicidae) Feeding Behavior, Survival, Oviposition Success and Fecundity}, journal = {Plos One}, publisher = {Public Library Science}, year = {2013}, volume = {8}, number = {3}, pages = {e59933}, doi = {10.1371/journal.pone.0059933} } |
| Tristao-Sa R, Kubelka CF, Zandonade E, Zagne SMO, Rocha NDM, Zagne LO, Araujo NF, Amin B, Fazoli F, de Souza LJ, Cruz OG, da Cunha RV, do Nascimento D, Froes IB and Nogueira RMR (2012), "Clinical and hepatic evaluation in adult dengue patients: a prospective two-month cohort study", Revista Da Sociedade Brasileira De Medicina Tropical., November, 2012. Vol. 45(6), pp. 675-681. Soc Brasileira Medicina Tropical. |
| Abstract: Introduction: To analyze the liver dysfunction and evolution of signs and symptoms in adult dengue patients during a two-month follow-up period. Methods: A prospective cohort study was conducted in Campos dos Goytacazes, Rio de Janeiro, Brazil, from January to July, 2008. The evolution of laboratory and clinical manifestations of 90 adult dengue patients was evaluated in five scheduled visits within a two-month follow-up period. Twenty controls were enrolled for the analysis of liver function. Patients with hepatitis B, hepatitis C, those known to be human immunodeficiency virus (HIV) seropositive and pregnant women were excluded from the study. Results: At the end of the second month following diagnosis, we observed that symptoms persisted in 33.3% (30/90) of dengue patients. We also observed that, 57.7% (15/26) of the symptoms persisted at the end of the second month. The most persistent symptoms were arthralgia, fatigue, weakness, adynamia, anorexia, taste alteration, and hair loss. Prior dengue virus (DENV) infection did not predispose patients to a longer duration of symptoms. Among hepatic functions, transaminases had the most remarkable elevation and in some cases remained elevated up to the second month after the disease onset. Alanine aminotransferase (ALT) levels overcame aspartate aminotransferase (AST) during the convalescent period. Male patients were more severely affected than females. Conclusions: Dengue fever may present a wide number of symptoms and elevated liver transaminases at the end of the second month. |
BibTeX: @article{Tristao-Sa2012, author = {Tristao-Sa, R. and Kubelka, C. F. and Zandonade, E. and Zagne, S. M. O. and Rocha, N. D. M. and Zagne, L. O. and Araujo, N. F. and Amin, B. and Fazoli, F. and de Souza, L. J. and Cruz, O. G. and da Cunha, R. V. and do Nascimento, D. and Froes, I. B. and Nogueira, R. M. R.}, title = {Clinical and hepatic evaluation in adult dengue patients: a prospective two-month cohort study}, journal = {Revista Da Sociedade Brasileira De Medicina Tropical}, publisher = {Soc Brasileira Medicina Tropical}, year = {2012}, volume = {45}, number = {6}, pages = {675--681} } |
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