RESUMO
In 2018-2019, we conducted mosquito collections in a municipal vehicle impound yard, which is 10 km from the Serra do Mar Environmental Protection Area in Santo André, SP, Brazil. Our aim is to study arboviruses in the impound yard, to understand the transmission of arboviruses in an urban environment in Brazil. We captured the mosquitoes using human-landing catches and processed them for arbovirus detection by conventional and quantitative RT-PCR assays. We captured two mosquito species, Aedes aegypti (73 total specimens; 18 females and 55 males) and Ae. albopictus (34 specimens; 27 females and 7 males). The minimum infection rate for DENV-2 was 11.5 per 1000 (CI95%: 1-33.9). The detection of DENV-2 RNA in an Ae. albopictus female suggests that this virus might occur in high infection rates in the sampled mosquito population and is endemic in the urban areas of Santo André. In addition, Guadeloupe mosquito virus RNA was detected in an Ae. aegypti female. To our knowledge, this was the first detection of the Guadeloupe mosquito virus in Brazil.
RESUMO
Serine peptidase inhibitor (serpin) is the name given to the superfamily of proteins with wide range of biological functions, and that the main feature is the inhibition of serine proteases. Here we describe the inhibitory characterization of a serpin from Gloeobacter violaceus that we named vioserpin. The serpin presented a high specificity to inhibit trypsin-like enzymes with a rapid inhibition rate constant (2.1 × 10(6) M(-1) s(-1)). We also demonstrated that the inhibitory activity of the vioserpin is influenced by the concentration of heparin, and this finding may throw a new light on understanding the molecular evolution of serpins.
Assuntos
Cianobactérias , Heparina/metabolismo , Inibidores de Serina Proteinase/farmacologia , Sequência de Aminoácidos , Animais , Bovinos , Humanos , Cinética , Camundongos , Filogenia , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Inibidores de Serina Proteinase/química , Inibidores de Serina Proteinase/isolamento & purificação , Inibidores de Serina Proteinase/metabolismo , Tripsina/metabolismoRESUMO
Mayaro virus (MAYV) is widely distributed throughout South America and is the etiologic agent of Mayaro fever, an acute febrile illness often presenting with arthralgic manifestations. The true incidence of MAYV infection is likely grossly underestimated because the symptomatic presentation is very similar to that of dengue fever and other acute febrile tropical diseases. We report the complete genome sequence of a MAYV isolate detected from an Acrelândia patient presenting with fever, chills, and sweating, but with no arthralgia. Results show that this isolate belongs to genotype D and is closely related to Bolivian strains. Our results suggest that the Acre/Mayaro strain is closely related to the progenitor of these Bolivian strains that were isolated between 2002 and 2006.
Assuntos
Infecções por Alphavirus/epidemiologia , Alphavirus/isolamento & purificação , Adulto , Alphavirus/genética , Infecções por Alphavirus/virologia , Sequência de Bases , Brasil/epidemiologia , Feminino , Humanos , Dados de Sequência Molecular , FilogeniaRESUMO
An isolate of Trypanosoma cruzi obtained from P. megistus captured in the peridomicile area of a home in Santo Antonio do Jardim city in the State of Sao Paulo, denominated T. cruzi Mogi, was characterized biologically and molecularly. The RFLP analysis of the D7 divergent domain in the 24Sα rDNA and of the mini-exon positioned the T. cruzi isolate within the TcI group. Phylogenetic analysis performed with the trypanosomatid barcode confirmed that the isolate belongs to the TcI group, with high homology to the 3014 c1 T.cruzi strain. The biological characterization of the isolate in rats showed a prepatent period of about 8 days, low parasitemia and tropism for cardiac, skeletal and colonic muscles. In Swiss mice the T. cruzi Mogi isolate showed a prepatent period of about 22 days, intermittent parasitemia in some animals, and tropism for cardiac and colonic muscles. Despite the inherent difficulty of identifying correlations amongst the molecular and biological characteristics of different T. cruzi groups, the tropism for colonic muscle demonstrated by T. cruzi Mogi represented a peculiarity of this isolate within the TcI group.
Assuntos
Panstrongylus/parasitologia , Trypanosoma cruzi/isolamento & purificação , Trypanosoma cruzi/patogenicidade , Estruturas Animais/parasitologia , Animais , Brasil , Doença de Chagas/parasitologia , Doença de Chagas/patologia , Código de Barras de DNA Taxonômico , Impressões Digitais de DNA , DNA de Protozoário/genética , DNA Ribossômico/genética , Modelos Animais de Doenças , Masculino , Camundongos , Polimorfismo de Fragmento de Restrição , Ratos Wistar , Trypanosoma cruzi/classificação , Trypanosoma cruzi/genéticaRESUMO
A comparison of dengue virus (DENV) antibody levels in paired serum samples collected from predominantly DENV-naive residents in an agricultural settlement in Brazilian Amazonia (baseline seroprevalence, 18.3%) showed a seroconversion rate of 3.67 episodes/100 person-years at risk during 12 months of follow-up. Multivariate analysis identified male sex, poverty, and migration from extra-Amazonian states as significant predictors of baseline DENV seropositivity, whereas male sex, a history of clinical diagnosis of dengue fever, and travel to an urban area predicted subsequent seroconversion. The laboratory surveillance of acute febrile illnesses implemented at the study site and in a nearby town between 2004 and 2006 confirmed 11 DENV infections among 102 episodes studied with DENV IgM detection, reverse transcriptase-polymerase chain reaction, and virus isolation; DENV-3 was isolated. Because DENV exposure is associated with migration or travel, personal protection measures when visiting high-risk urban areas may reduce the incidence of DENV infection in this rural population.
Assuntos
Dengue/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/sangue , Brasil , Criança , Pré-Escolar , Estudos Transversais , Dengue/diagnóstico , Dengue/prevenção & controle , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco , Estudos Soroepidemiológicos , Caracteres SexuaisRESUMO
Triatoma infestans, the main vector of Chagas disease, has nearly been eliminated from Brazil. Nevertheless, other triatominae species are involved in the domiciliation process, including Triatoma rubrovaria in Rio Grande do Sul State (RS). Previous studies showed that 1.6% of the T. rubrovaria specimens collected at the rural district of Quaraí, RS, were naturally infected by Trypanosoma cruzi. In this study, five T. cruzi isolates obtained from infected triatomines were characterized molecularly and biologically. Genotyping of the T. cruzi isolates showed that they belong to lineage IIc of T. cruzi (TCIIc). Biological characterization showed miotropism and myositis during acute and chronic phases of infection, respectively. Virulence and mortality rates were variable among isolates. To our knowledge, this study corresponds to the first characterization of T. cruzi isolates from T. rubrovaria and the first description of TCIIc in the sylvatic cycle of T. cruzi from the southern region of Brazil.
Assuntos
Doença de Chagas/transmissão , Insetos Vetores/parasitologia , Triatoma/parasitologia , Trypanosoma cruzi/classificação , Animais , Brasil , Genótipo , Camundongos , Músculo Esquelético/parasitologia , Músculo Esquelético/patologia , Parasitemia , Filogenia , População Rural , Fatores de Tempo , Trypanosoma cruzi/genética , Trypanosoma cruzi/isolamento & purificação , Trypanosoma cruzi/patogenicidade , VirulênciaRESUMO
Objetivo: Investigar se a presença de infecção porHelicobacter pylori está associada à ocorrência deurticária crônica idiopática utilizando como controledoadores de sangue do Hemocentro da Faculdade de Medicina de Marília (FAMEMA). Material e métodos: Com o emprego dos kits Enzygnostâ Anti-H. pylori II/ IgA e IgG (Dade Behring Marburg GmbH), foram comparadas as análises sorológicas anti-H. pylori de dois grupos. O primeiro com 21 pacientes com quadro clínico de urticária crônica idiopática e outro de 254 doadores de sangue. Foram ainda obtidos alguns dados epidemiológicos dos indivíduos doadores de sangue como a renda mensal familiar, o grau de escolaridade e número de pessoas na família para associação com o diagnóstico sorológico deH. pylori. As associações entre as diferentes variáveisforam analisadas estatisticamente com o emprego do teste de Qui-quadrado. Resultados: A prevalência de infecção por H. pylori determinada pelo título sorológico de IgG e/ou IgA anti H. pylori foi de 57 per cent para os dois grupos de indivíduos analisados neste estudo. Dentre os parâmetros epidemiológicos investigados, apenas o grau de escolaridade apresentou associação estatisticamente significante com o diagnóstico sorológico de H. pylori,sendo que indivíduos com até o primeiro grau tiverammaior prevalência de anticorpos IgG e/ou IgA que os indivíduos com nível superior e segundo grau (p<0,001).Conclusões: Não encontramos evidências da associação entre o H. pylori e urticária crônica, já que a prevalência de sorologia positiva na população em geralfoi a mesma encontrada para pacientes com urticária.Os dados epidemiológicos mostraram que em média, os indivíduos doadores de sangue da região de Marília possuem condições sócio-econômicas acima da média nacional brasileira e a prevalência de H. pylori nestes indivíduos é comparável aos valores encontrados para países em desenvolvimento.