55 research outputs found
VĂrus da dengue : novas abordagens para o estudo da neuropatogĂȘnese
Orientadora : DrÂȘ Claudia N. Duarte dos SantosTese (doutorado) - Universidade Federal do ParanĂĄ, Setor de CiĂȘncias BiolĂłgicas, Programa de PĂłs-Graduação em Biologia Celular e Molecular. Defesa: Curitiba, 10/01/2013Inclui referĂȘnciasĂrea de concentração : Biologia molecularResumo: A dengue constitui um grande problema de saĂșde pĂșblica nas regiĂ”es tropicais e subtropicais do globo. Apesar dos grandes avanços na biologia do vĂrus da dengue (DENV), muitos aspectos da patogĂȘnese permanecem desconhecidos. A ausĂȘncia de um modelo animal adequado, que mimetize o espectro da infecção pelo DENV, institui uma das principais dificuldades no estudo da dengue. MĂșltiplas linhas de evidĂȘncias indicam que a gravidade da doença Ă©, provavelmente, determinada pela interação entre fatores virais e do hospedeiro. Alguns determinantes genĂ©ticos de virulĂȘncia intrĂnseca do DENV no hospedeiro foram identificados, no entanto, nenhuma correlação conclusiva entre genĂłtipo viral, transmissibilidade do vĂrus e patogenicidade foi estabelecida. Neste estudo, foi utilizado um painel de DENV tipo 1 (DENV-1) recombinante para investigar o papel de determinantes genĂ©ticos de virulĂȘncia previamente identificados em duas cepas altamente neurovirulentos (FGA/NA D1D e FGA/NA P6). A replicação e capacidade de produção de partĂculas virais infecciosas foram avaliadas in vivo (modelo de camundongos imunocompetentes), in vitro (linhagens celulares humanas e de insetos) e ex vivo (cĂ©lulas dendrĂticas derivadas de monĂłcitos humanos, mdDCs). Os resultados demonstraram que a associação das mutaçÔes na proteĂna de envelope (E) e no domĂnio helicase da proteĂna NS3 (NS3hel) apresentam um efeito sinĂ©rgico na modulação do fitness viral in vitro e in vivo, aumentando a sĂntese de RNA, a carga viral, a robustez da resposta imune e mortalidade dos animais. No entanto, os vĂrus contendo apenas as mutaçÔes na proteĂna NS3 (NS3435 e NS3480) foram capazes de se replicar eficientemente no SNC de camundongos, de causar encefalite e altas taxas de mortalidade, o que sugere que essas mutaçÔes desempenham um papel importante na modulação da replicação viral in vivo. As mutaçÔes NS3435 e NS3480 aumentam tambĂ©m o fitness viral em mdDCs, aumentando a sĂntese de RNA e a carga viral. AlĂ©m disso, foi demonstrado que as mutaçÔes no domĂnio helicase nĂŁo afetam significativamente a atividades de protease e NTPase da NS3 in vitro. Apesar do elevado nĂvel de replicação do RNA viral, a infecção pelo DENV foi capaz de reduzir a produção de IFN tipo I em mdDCs apĂłs estĂmulo dos receptores do tipo Toll (TLR). Os resultados apresentados neste trabalho mostram que a presença de uma Ășnica mutação no genoma do DENV aumenta o fitness viral in vivo, in vitro e ex vivo e Ă© suficiente para modular a resposta imunolĂłgica do hospedeiro e promover uma infecção produtiva. Dadas as limitaçÔes atuais para a compreensĂŁo das bases moleculares da patogĂȘnese da dengue, estes resultados podem contribuir para fornecer subsĂdios sobre as interaçÔes vĂrus/hospedeiro e novas informaçÔes sobre os mecanismos da biologia bĂĄsica da dengue.Abstract: Dengue constitutes a significant public health problem in tropical and subtropical regions of the world. Despite major advances in dengue virus (DENV) biology, many aspects of dengue pathogenesis remain largely unknown. The absence of a suitable animal model, mimicking the full spectrum of DENV infections, is one of the main difficulties in studying dengue disease. Multiple lines of evidence indicate that disease severity is probably determined by the interplay of viral and host factors. Some viral genetic determinants of the intrinsic virulence of DENV in the host have been identified; nevertheless, no conclusive evidence of a correlation between viral genotype and virus transmissibility and pathogenicity has been obtained. In this study, we used a panel of recombinant DENV type 1 (DENV-1) to investigate the role of genetic determinants of virulence previously identified in two highly neurovirulent strains (FGA/NA d1d e FGA/NA P6). The replication and viral production capacity of the recombinant viruses were assessed in vivo (immunocompetent mice model), in vitro (human and insect cells lines) and ex vivo (dendritic cells derived from human monocytes, mdDCs). Our results demonstrated that paired mutations in the envelope protein (E) and in the helicase domain of the NS3 (NS3hel) protein have a synergistic effect enhancing viral fitness both in vitro and in vivo by increasing RNA synthesis and viral load, the strength of the immune response and animal mortality. However, the virus carrying mutations only at the NS3 protein (NS3435 and NS3480) was able to replicate efficiently in the CNS of mice and to cause encephalitis and high mortality rates, suggesting that these mutations play an important role on the viral fitness modulation in vivo. These mutations also enhanced viral fitness in mdDCs by increasing RNA synthesis and viral load. Additionally, it has been demonstrated that the mutations NS3435 and NS3480 in the helicase domain do not significantly affect the protease and NTPase activities of NS3 in vitro. Despite the high level of RNA replication, DENV reduces the ability of mdDCs to produce type I IFN triggered by Toll-like receptor (TLR) signaling. The results presented herein show that a single mutation in DENV genome enhances viral fitness in vivo, in vitro and ex vivo and is enough to subvert the host immune response and establish a productive infection. Given current limitations to our understanding of the molecular basis of dengue pathogenesis, these results could contribute to provide insights into virus/host interactions and new information about the mechanisms of basic dengue biology
Neuroadaptaçao de virus dengue em modelo murino : identificaçao de marcadores moleculares
Orientadora : DrS Claudia N. Duarte dos SantosDissertaçao (mestrado) - Universidade Federal do ParanĂĄ, Setor de Ciencias BiolĂłgicas, Programa de PĂłs-Graduaçao em Biologia Celular e Molecular. Defesa: Curitiba, 2008Inclui bibliografiaO vĂrus da dengue (DENV), um membro do gĂȘnero Flavivirus (famĂlia Flaviviridae), Ă©
um arbovĂrus que causa severa doença em humanos. O espectro da doença varia
desde uma febre indiferenciada (FD) até a febre hemorrågica da dengue (FHD), que
pode evoluir para a sĂndrome do choque da dengue (SCD) e morte. Mais
recentemente, o perfil clĂnico da infecção pelo DENV estĂĄ mudando e um aumento
significativo de casos clĂnicos com manifestaçÔes neurolĂłgicas vem sendo
documentado. O(s) mecanismo(s) pelo qual o DENV pode causar doença grave e a
contribuição de fatores virais e do hospedeiro para o desenvolvimento dos quadros
clĂnicos severos, nĂŁo estĂĄ completamente compreendido. A falta de um modelo
animal, que reflita as formas graves da doença é um obståculo para se estudar
alguns aspectos da patogĂȘnese da dengue. O sistema nervoso central (SNC) de
camundongos neonatos tem sido utilizado como modelo para compreender a
fisiopatologia da doença. Para confirmar e definir o envolvimento de substituiçÔes de
aminoåcidos no genoma viral que pudessem estar relacionadas com a aquisição de
um fenĂłtipo de neurovirulĂȘncia do DENV em camundongos, a cepas do sorotipo 1
do vĂrus (DENV-1) FGA/89 foi adapta ao SNC de camundongos neonatos suĂços. A
capacidade da nova variante neuroadaptada replicar-se no SNC e provocar
encefalite foi analisada. Durante o processo de neuroadaptação do vĂrus FGA/89,
uma substituição de aminoĂĄcido na proteĂna de envelope (E) e duas na proteĂna
não-estrutural 3 (NS3) foram observadas. Estas mutaçÔes foram identificadas
primeiramente nos vĂrus resultantes da terceira passagem (FGA/NA P3) e
observadas até a sexta passagem. As substituiçÔes E Phe402/Leu e NS3 Leu480/Ser
identificadas na variante FGA/NA P3-P6, embora nĂŁo idĂȘnticas Ă quelas observadas
em FGA/NA d1d (outra variante neuroadaptada a partir da mesma cepa parental,
FGA/89), mapeiam nos mesmos domĂnios, sugerindo um papel potencial dessas
proteĂnas na aquisição do fenĂłtipo de neurovirulĂȘncia do DENV-1 em camundongos.
Com o intuito de confirmar o envolvimento dessas mutaçÔes, um isolado clĂnico
recente (BR/01-MR) foi submetido ao mesmo processo de neuroadaptação. Embora
a variante MR/NA P7 tenha se mostrado mais neurovirulenta do que a variante
FGA/NA P6, ocasionando danos severos no SNC de camundongos, caracterizados
por leptomeningite e necrose de substĂąncia branca, nĂŁo foi possĂvel identificar a
presença de partĂculas infecciosas nem do RNA viral em cada uma das passagens
do vĂrus. No entanto, atravĂ©s de ensaios microscopia eletrĂŽnica e imunocitoquĂmica
de secçÔes do SNC de camundongos foi possĂvel observar tanto a presença de
partĂculas virais como das proteĂnas E e NS1, sugerindo que os danos no SNC dos
camundongos infectados foi uma conseqĂŒĂȘncia direta da infecção pelo vĂrus. Os
resultados obtidos neste trabalho permitiram demonstrar a implicação das proteĂnas
E e NS3 no processo de neurovirulĂȘncia do vĂrus FGA/NA 89 e que as variantes
neuroadaptadas apresentam a capacidade de infectar as células do SNC de
camundongos neonatos e ocasionar danos extensivos nos tecidos como
leptomeningite e encefalite. Um maior conhecimento sobre os mecanismos
envolvidos na patogĂȘnese da dengue poderĂĄ contribuir para o delineamento de
estratégias antivirais direcionadas e eventualmente o controle da infecção.Dengue virus (DENV), a member of the Flavivirus genus (family Flaviviridae), is an
arthropod-borne virus that cause severe disease in humans. The spectrum of illness
ranges from a self-limiting fever (DF) to dengue hemorrhagic fever (DHF), which can
progress to dengue shock syndrome and death. More recently, the clinical
presentation of DENV infection is changing and a significant increase of cases with
neurological manifestations has been documented. The precise mechanim(s) by
which DEN viruses cause severe disease is still not understood. It has been inferred
that both immunological and viral factors determine the severity of disease. The lack
of an animal model that reflects the severe forms of the disease is an obstacle to
study some aspects of dengue pathogenesis. The central nervous system (CNS) of
newborn mice has been used as a model system to study the pathophysiology of
dengue disease. To confirm and to define the involvement of the amino acid
substitutions in the viral genome that could be related to the acquisition of DENV
neurovirulent phenotype for mice, we adapted a strains of dengue virus type 1,
FGA/89, in CNS of newborn Swiss mice. The capacity of the neuroadapted variants
to replicate in CNS and to cause encephalitis was analyzed. One amino acid
mutation in the envelope E protein and two amino acid mutations in the nonstructural
NS3 protein were observed during the neuroadaptation process of FGA/89. These
mutations were first identified in FGA/NA P3 and fixed until the sixth passage. The
substitutions E Phe402/Leu and NS3 Leu480/Ser identified in FGA/NA P3-P6, although
not identical to those observed in FGA/NA d1d (another neuroadapted variant from
the same parental strain, FGA/89), mapped to the same domain, suggesting a
potential role of these proteins in the acquisition of DENV mice neurovirulent
phenotype. Aiming to confirm the involvement of these mutations in dengue
neurovirulence, a recent clinical isolate (BR/01-MR) was submitted to the same
protocol of neuroadaptation. The neurovirulent variant MR/NA P7 was more
neurovirulent for newborn Swiss mice, compared to FGA/NA P6 variant, causing
severe damage in CNS of mice, characterized by leptomeningitis and necrosis of
white matter. Despite of all these findings, it was not possible to identify neither the
presence of viral infectious particle nor the presence of the viral RNA in all the
passages of the virus in mice brains. However, by electron microscopy and immune
electron microscopy assays it was possible to observe the presence of viral particles
and viral proteins E and NS1 in the sections of the CNS of mice, suggesting that the
damage observed in the CNS was a direct result of virus infection. Results obtained
in this work demonstrate the implication of the proteins E and NS3 in the process of
neuroadaption of the virus FGA/89 and that the neurovirulent variants have the ability
to infect CNS of newborn mice causing extensive tissue damage as leptomeningitis
and encephalitis. A better knowledge about molecular markers and mechanisms that
could be involved in the dengue pathogenesis would be useful for developing new
targets to antiviral strategies and eventually control of infection
RPA-Approach to the Excitations of the Nucleon, Part II: Phenomenology
The tensor-RPA approach developed previously in part I is applied to the
Nambu-Jona-Lasinio (NJL) model. As a first step we investigate the structure of
Dirac-Hartree-Fock solutions for a rotationally and isospin invariant
ground-state density. Whereas vacuum properties can be reproduced, no solitonic
configuration for a system with unit baryon number is found. We then solve the
tensor-RPA equation employing simple models of the nucleon ground state. In
general the ph interaction effects a decrease of the excited states to lower
energies. Due to an enhanced level density at low energies the obtained spectra
cannot be matched with the experimental data when a standard MIT-bag
configuration is used. However, when the size of the nucleon quark core is
reduced to approximately 0.3 fm a fair description of the baryon spectrum in
the positive-parity channel is achieved. For this purpose the residual
interaction turns out to be crucial and leads to a significant improvement
compared with the mean-field spectra.Comment: 33 pages, Latex, 9 Postscpript figures, section on the excited states
has been completely rewritten after error was detected, results are now much
more encouragin
Genome-wide analyses reveal a highly conserved Dengue virus envelope peptide which is critical for virus viability and antigenic in humans.
Targeting regions of proteins that show a high degree of structural conservation has been proposed as a method of developing immunotherapies and vaccines that may bypass the wide genetic variability of RNA viruses. Despite several attempts, a vaccine that protects evenly against the four circulating Dengue virus (DV) serotypes remains elusive. To find critical conserved amino acids in dengue viruses, 120 complete genomes of each serotype were selected at random and used to calculate conservation scores for nucleotide and amino acid sequences. The identified peptide sequences were analysed for their structural conservation and localisation using crystallographic data. The longest, surface exposed, highly conserved peptide of Envelope protein was found to correspond to amino acid residues 250 to 270. Mutation of this peptide in DV1 was lethal, since no replication of the mutant virus was detected in human cells. Antibodies against this peptide were detected in DV naturally infected patients indicating its potential antigenicity. Hence, this study has identified a highly conserved, critical peptide in DV that is a target of antibodies in infected humans
Synergistic Interactions between the NS3hel and E Proteins Contribute to the Virulence of Dengue Virus Type 1
Dengue virus constitutes a significant public health problem in tropical regions of the world. Despite the high morbidity and mortality of this infection, no effective antiviral drugs or vaccines are available for the treatment or prevention of dengue infections. The profile of clinical signs associated with dengue infection has changed in recent years with an increase in the number of episodes displaying unusual signs. We use reverse genetics technology to engineer DENV-1 viruses with subsets of mutations previously identified in highly neurovirulent strains to provide insights into the molecular mechanisms underlying dengue neuropathogenesis. We found that single mutations affecting the E and NS3hel proteins, introduced in a different genetic context, had a synergistic effect increasing DENV replication capacity in human and mosquito derived cells in vitro. We also demonstrated correlations between the presence of these mutations and viral replication efficiency, viral loads, the induction of innate immune response genes and pathogenesis in a mouse model. These results should improve our understanding of the DENV-host cell interaction and contribute to the development of effective antiviral strategies
A utilização do ensino hĂbrido no ensino mĂ©dio presencial de matemĂĄtica
Tendo-se em vista a ampla grade curricular do Ensino MĂ©dio, fez-se uma pesquisa numa turma de 2Âș ano do Ensino MĂ©dio da ETE Monteiro Lobato, objetivando-se compreender se a utilização do ensino hĂbrido, utilizando o AVA Google sala de aula, melhora o desempenho dos estudantes na disciplina de MatemĂĄtica do Ensino MĂ©dio presencial. Acredita-se que o ensino hĂbrido proporciona autonomia aos discentes, possibilitando maior aprofundamento dos conteĂșdos, alĂ©m de oportunizar que mais recursos possam ser utilizados. Para isso, buscou-se aplicar a metodologia do ensino hĂbrido, por intermĂ©dio do Google sala de aula, analisar como os estudantes reagem Ă inserção destes recursos digitais, identificar quais as contribuiçÔes da utilização do AVA juntamente com o ensino hĂbrido, compreender como avaliar os alunos no ensino hĂbrido, verificar e analisar se melhorou o desempenho dos estudantes e identificar se essa melhora Ă© devido ao AVA ou ao ensino hĂbrido. A abordagem nĂŁo correu como imaginado, deixando muitas dĂșvidas. Os discentes se mostraram relutantes com a nova metodologia e a docente nĂŁo soube como proceder. Mesmo com muitas falhas no decorrer da aplicação, a pesquisadora acredita que com ajustes e um pouco mais de estudo e dedicação Ă© possĂvel incluir o ensino hĂbrido no Ensino MĂ©dio presencial.Having in mind that High School has a broad curriculum, a research was made in one High School sophomore class in ETE Monteiro Lobato, aiming to understand if the use of blended learning, using VLAE Google Classroom, improves the performance of students in High School mathematics class. It is believed that blended learning provides autonomy to the students, making it possible for them to deepen their knowledge in subjects of their interest, besides giving an opportunity to use more resources. In order to do that it was sought how to apply the blended learning method, through Google Classroom, how to analyse the studentsâ reaction to the insertion of those digital resources, how to identify the contributions of using VLAE alongside blended learning, how to comprehend the means of evaluation of the students in blended learning, how to verify and analyse if the studentsâ performance was improved and identify if this improvement was due to the VLAE or the blended learning. The approach did not occur as imagined, leaving a lot of doubts. The students seemed reluctant with the new method and the teacher did not know how to proceed. Even with the many failures during the application, the researcher believes that with adjustments and more studying and dedication it is possible to include blended learning in presential High School
Neuroadaptaçao de virus dengue em modelo murino : identificaçao de marcadores moleculares
Orientadora : DrS Claudia N. Duarte dos SantosDissertaçao (mestrado) - Universidade Federal do ParanĂĄ, Setor de Ciencias BiolĂłgicas, Programa de PĂłs-Graduaçao em Biologia Celular e Molecular. Defesa: Curitiba, 2008Inclui bibliografiaO vĂrus da dengue (DENV), um membro do gĂȘnero Flavivirus (famĂlia Flaviviridae), Ă©
um arbovĂrus que causa severa doença em humanos. O espectro da doença varia
desde uma febre indiferenciada (FD) até a febre hemorrågica da dengue (FHD), que
pode evoluir para a sĂndrome do choque da dengue (SCD) e morte. Mais
recentemente, o perfil clĂnico da infecção pelo DENV estĂĄ mudando e um aumento
significativo de casos clĂnicos com manifestaçÔes neurolĂłgicas vem sendo
documentado. O(s) mecanismo(s) pelo qual o DENV pode causar doença grave e a
contribuição de fatores virais e do hospedeiro para o desenvolvimento dos quadros
clĂnicos severos, nĂŁo estĂĄ completamente compreendido. A falta de um modelo
animal, que reflita as formas graves da doença é um obståculo para se estudar
alguns aspectos da patogĂȘnese da dengue. O sistema nervoso central (SNC) de
camundongos neonatos tem sido utilizado como modelo para compreender a
fisiopatologia da doença. Para confirmar e definir o envolvimento de substituiçÔes de
aminoåcidos no genoma viral que pudessem estar relacionadas com a aquisição de
um fenĂłtipo de neurovirulĂȘncia do DENV em camundongos, a cepas do sorotipo 1
do vĂrus (DENV-1) FGA/89 foi adapta ao SNC de camundongos neonatos suĂços. A
capacidade da nova variante neuroadaptada replicar-se no SNC e provocar
encefalite foi analisada. Durante o processo de neuroadaptação do vĂrus FGA/89,
uma substituição de aminoĂĄcido na proteĂna de envelope (E) e duas na proteĂna
não-estrutural 3 (NS3) foram observadas. Estas mutaçÔes foram identificadas
primeiramente nos vĂrus resultantes da terceira passagem (FGA/NA P3) e
observadas até a sexta passagem. As substituiçÔes E Phe402/Leu e NS3 Leu480/Ser
identificadas na variante FGA/NA P3-P6, embora nĂŁo idĂȘnticas Ă quelas observadas
em FGA/NA d1d (outra variante neuroadaptada a partir da mesma cepa parental,
FGA/89), mapeiam nos mesmos domĂnios, sugerindo um papel potencial dessas
proteĂnas na aquisição do fenĂłtipo de neurovirulĂȘncia do DENV-1 em camundongos.
Com o intuito de confirmar o envolvimento dessas mutaçÔes, um isolado clĂnico
recente (BR/01-MR) foi submetido ao mesmo processo de neuroadaptação. Embora
a variante MR/NA P7 tenha se mostrado mais neurovirulenta do que a variante
FGA/NA P6, ocasionando danos severos no SNC de camundongos, caracterizados
por leptomeningite e necrose de substĂąncia branca, nĂŁo foi possĂvel identificar a
presença de partĂculas infecciosas nem do RNA viral em cada uma das passagens
do vĂrus. No entanto, atravĂ©s de ensaios microscopia eletrĂŽnica e imunocitoquĂmica
de secçÔes do SNC de camundongos foi possĂvel observar tanto a presença de
partĂculas virais como das proteĂnas E e NS1, sugerindo que os danos no SNC dos
camundongos infectados foi uma conseqĂŒĂȘncia direta da infecção pelo vĂrus. Os
resultados obtidos neste trabalho permitiram demonstrar a implicação das proteĂnas
E e NS3 no processo de neurovirulĂȘncia do vĂrus FGA/NA 89 e que as variantes
neuroadaptadas apresentam a capacidade de infectar as células do SNC de
camundongos neonatos e ocasionar danos extensivos nos tecidos como
leptomeningite e encefalite. Um maior conhecimento sobre os mecanismos
envolvidos na patogĂȘnese da dengue poderĂĄ contribuir para o delineamento de
estratégias antivirais direcionadas e eventualmente o controle da infecção.Dengue virus (DENV), a member of the Flavivirus genus (family Flaviviridae), is an
arthropod-borne virus that cause severe disease in humans. The spectrum of illness
ranges from a self-limiting fever (DF) to dengue hemorrhagic fever (DHF), which can
progress to dengue shock syndrome and death. More recently, the clinical
presentation of DENV infection is changing and a significant increase of cases with
neurological manifestations has been documented. The precise mechanim(s) by
which DEN viruses cause severe disease is still not understood. It has been inferred
that both immunological and viral factors determine the severity of disease. The lack
of an animal model that reflects the severe forms of the disease is an obstacle to
study some aspects of dengue pathogenesis. The central nervous system (CNS) of
newborn mice has been used as a model system to study the pathophysiology of
dengue disease. To confirm and to define the involvement of the amino acid
substitutions in the viral genome that could be related to the acquisition of DENV
neurovirulent phenotype for mice, we adapted a strains of dengue virus type 1,
FGA/89, in CNS of newborn Swiss mice. The capacity of the neuroadapted variants
to replicate in CNS and to cause encephalitis was analyzed. One amino acid
mutation in the envelope E protein and two amino acid mutations in the nonstructural
NS3 protein were observed during the neuroadaptation process of FGA/89. These
mutations were first identified in FGA/NA P3 and fixed until the sixth passage. The
substitutions E Phe402/Leu and NS3 Leu480/Ser identified in FGA/NA P3-P6, although
not identical to those observed in FGA/NA d1d (another neuroadapted variant from
the same parental strain, FGA/89), mapped to the same domain, suggesting a
potential role of these proteins in the acquisition of DENV mice neurovirulent
phenotype. Aiming to confirm the involvement of these mutations in dengue
neurovirulence, a recent clinical isolate (BR/01-MR) was submitted to the same
protocol of neuroadaptation. The neurovirulent variant MR/NA P7 was more
neurovirulent for newborn Swiss mice, compared to FGA/NA P6 variant, causing
severe damage in CNS of mice, characterized by leptomeningitis and necrosis of
white matter. Despite of all these findings, it was not possible to identify neither the
presence of viral infectious particle nor the presence of the viral RNA in all the
passages of the virus in mice brains. However, by electron microscopy and immune
electron microscopy assays it was possible to observe the presence of viral particles
and viral proteins E and NS1 in the sections of the CNS of mice, suggesting that the
damage observed in the CNS was a direct result of virus infection. Results obtained
in this work demonstrate the implication of the proteins E and NS3 in the process of
neuroadaption of the virus FGA/89 and that the neurovirulent variants have the ability
to infect CNS of newborn mice causing extensive tissue damage as leptomeningitis
and encephalitis. A better knowledge about molecular markers and mechanisms that
could be involved in the dengue pathogenesis would be useful for developing new
targets to antiviral strategies and eventually control of infection
A utilização do ensino hĂbrido no ensino mĂ©dio presencial de matemĂĄtica
Tendo-se em vista a ampla grade curricular do Ensino MĂ©dio, fez-se uma pesquisa numa turma de 2Âș ano do Ensino MĂ©dio da ETE Monteiro Lobato, objetivando-se compreender se a utilização do ensino hĂbrido, utilizando o AVA Google sala de aula, melhora o desempenho dos estudantes na disciplina de MatemĂĄtica do Ensino MĂ©dio presencial. Acredita-se que o ensino hĂbrido proporciona autonomia aos discentes, possibilitando maior aprofundamento dos conteĂșdos, alĂ©m de oportunizar que mais recursos possam ser utilizados. Para isso, buscou-se aplicar a metodologia do ensino hĂbrido, por intermĂ©dio do Google sala de aula, analisar como os estudantes reagem Ă inserção destes recursos digitais, identificar quais as contribuiçÔes da utilização do AVA juntamente com o ensino hĂbrido, compreender como avaliar os alunos no ensino hĂbrido, verificar e analisar se melhorou o desempenho dos estudantes e identificar se essa melhora Ă© devido ao AVA ou ao ensino hĂbrido. A abordagem nĂŁo correu como imaginado, deixando muitas dĂșvidas. Os discentes se mostraram relutantes com a nova metodologia e a docente nĂŁo soube como proceder. Mesmo com muitas falhas no decorrer da aplicação, a pesquisadora acredita que com ajustes e um pouco mais de estudo e dedicação Ă© possĂvel incluir o ensino hĂbrido no Ensino MĂ©dio presencial.Having in mind that High School has a broad curriculum, a research was made in one High School sophomore class in ETE Monteiro Lobato, aiming to understand if the use of blended learning, using VLAE Google Classroom, improves the performance of students in High School mathematics class. It is believed that blended learning provides autonomy to the students, making it possible for them to deepen their knowledge in subjects of their interest, besides giving an opportunity to use more resources. In order to do that it was sought how to apply the blended learning method, through Google Classroom, how to analyse the studentsâ reaction to the insertion of those digital resources, how to identify the contributions of using VLAE alongside blended learning, how to comprehend the means of evaluation of the students in blended learning, how to verify and analyse if the studentsâ performance was improved and identify if this improvement was due to the VLAE or the blended learning. The approach did not occur as imagined, leaving a lot of doubts. The students seemed reluctant with the new method and the teacher did not know how to proceed. Even with the many failures during the application, the researcher believes that with adjustments and more studying and dedication it is possible to include blended learning in presential High School
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