RESUMOArbovírus (Arthropod-borne virus) são assim designados pelo fato de parte de seu ciclo de replicação ocorrer nos insetos, podendo ser transmitidos aos seres humanos e outros animais pela picada de artrópodes hematófagos. Dos mais de 545 espécies de arbovírus conhecidos, cerca de 150 causam doenças em humanos. As arboviroses têm representado um grande desafio à saúde pública, devido às mudanças climáticas e ambientais e aos desmatamentos que favorecem a amplificação, a transmissão viral, além da transposição da barreira entre espécies. Neste trabalho de revisão discorremos sobre as características gerais, patogenia e epidemiologia dos arbovírus e das infecções resultantes, que têm emergido ou reemergido no Brasil nas últimas décadas. Pela potencial ameaça que significam à saúde humana no Brasil, os arbovírus mencionados neste trabalho merecem especial atenção no que refere ao estabelecimento/consolidação de programas compulsórios de controle e combate eficazes das doenças em humanos e animais domésticos. Estima-se que haja mais de 545 espécies de arbovírus, dentre as quais, mais de 150 relacionadas com doenças em seres humanos, sendo a maioria zoonótica. São mantidos em ciclo de transmissão entre artrópodes (vetores) e reservatórios vertebrados como principais hospedeiros amplificadores 2,3 . PalavrasAs arboviroses têm se tornado importantes e constantes ameaças em regiões tropicais devido às rápidas mudanças climáticas, desmatamentos, migração populacional, ocupação desordenada de áreas urbanas, precariedade das condições sanitárias que favorecem a amplificação e transmissão viral 1 . São transmitidas pelo sangue de pacientes virêmicos, por insetos hematófagos, o que não deixa de ser uma preocupação na doação de sangue em áreas endêmicas 2 . Casos de transmissão do vírus Oeste do Nilo (WNV) entre seres humanos, por meio de transfusões de sangue e transplante de órgãos, têm sido relatados, entretanto todos os arbovírus que produzem viremia são potencialmente passíveis de desencadearem infecções iatrogênicas 4,5 .O único continente onde os arbovírus não são endêmicos é o Antártico. Estes vírus tendem a ter uma distribuição geográfica e climática restrita, como parte de um subsistema ecológico especial representado pelos vírus, vetores, hospedeiros amplificadores e reservatórios 1 .O Brasil é constituído por uma grande extensão terrestre (pouco mais de 8.500.000 km 2 ), situado em uma área predominantemente tropical, com extensas florestas na Região Amazônica, além de florestas no leste, sudeste e litoral sul. Apresenta também uma

Aims:  Agaricus brasiliensis (previously named Agaricus blazei ss. Heinem), also known as the sun mushroom is native of Southeast Brazil, and is widely consumed, mainly in the form of tea, due to its nutritional and pharmacological properties. In this study, we tested aqueous (AqE) and ethanol (EtOHE) extracts and an isolated polysaccharide (PLS) from the fruiting body of A. brasiliensis, for antiviral activity against poliovirus type 1 in HEp‐2 cells. Methods and Results:  The evaluation of the time of addition by plaque assay showed that when AqE, PLS and EtOHE were added, just after the virus inoculation (time 0 h), there was a concentration‐dependent reduction in the number of plaques up to 50%, 67% and 88%, respectively, with a selectivity index (SI) of 5·4, 9·9 and 12·3, respectively. Conclusions:  The test substances showed antiviral activity and were more effective when added during the poliovirus infection. As they had little effect on reducing viral adsorption and did not show any virucidal effect, we suggest that they act at the initial stage of the replication of poliovirus. Significance and Impact of the Study:  These results corroborate that basidiomycetes can be a rich source of potential antiviral compounds.

BackgroundLentinula edodes, known as shiitake, has been utilized as food, as well as, in popular medicine, moreover, compounds isolated from its mycelium and fruiting body have shown several therapeutic properties. The aim of this study was to determine the antiviral activity of aqueous (AqE) and ethanol (EtOHE) extracts and polysaccharide (LeP) from Lentinula edodes in the replication of poliovirus type 1 (PV-1) and bovine herpes virus type 1 (BoHV-1).MethodsThe time-of-addition assay was performed at the times -2, -1, 0, 1 and 2 h of the infection. The virucidal activity and the inhibition of viral adsorption were also evaluated. Plaque assay was used to monitor antiviral activity throughout.ResultsThe AqE and LeP were more effective when added at 0 h of infection, however, EtOHE was more effective at the times 1 h and 2 h of the infection. AqE, EtOHE and LeP showed low virucidal activity, and the inhibition of viral adsorption was not significant.ConclusionsThe results allowed us to conclude that AqE, EtOHE and LeP act on the initial processes of the replication of both strains of virus.

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Between May and August in 2003, a total of 251 fecal samples were collected from children and adults with diarrhea (5 inpatients and 246 outpatients) at a private hospital in the city of Ponta Grossa, the state of Paraná, Brazil. Group A rotavirus was detected in 71 of 251 (28.3%) specimens: 55 (77.5%) from children under 5 years of age and 16 (22.5%) from individuals aged 6-72 years. All 71 strains exhibited a "long" RNA pattern when analyzed by PAGE. Sixty-one positive samples that yielded enough RNA were submitted to PCR genotyping. The most frequent G/P genotype combination detected was G1P[8] (86.9%; 53/61) followed by G9P[8] (3.3%; 2/61) and G12P[9] (1.6%; 1/61). Rotaviruses with G2, G3, G4, P[4], or P[6] specificity were not detected. For three strains (4.9%) bearing G1 genotype, the VP4 specificity could no be determined, and two specimens (3.3%) remained G/P non-typeable. One rotavirus strain (HC91) bearing G12P[9] genotype with a "long" electropherotype was isolated from an 11-month-old boy with diarrhea for the first time in Brazil. The cell-culture grown HC91 strain was shown to belong to serotype G12 by neutralization.

Herpes simplex virus (HSV) infections are common and widespread; nevertheless, their outcome can be of unpredictable prognosis in neonates and in immunosuppressed patients. Anti-HSV therapy is effective, but the emergence of drug-resistant strains or the drug toxicity that hamper the treatment is of great concern. Vaccine has not yet shown relevant benefit; therefore, palliative prophylactic measures have been adopted to prevent diseases. This short review proposes to present concisely the history of HSV, its taxonomy, physical structure, and replication and to explore the pathogenesis of the infection, clinical manifestations, laboratory diagnosis, treatment, prophylaxis and epidemiology of the diseases.

beta-Glucans (BGs) are polysaccharides that are found in the cell walls of organisms such as bacteria, fungi, and some cereals. The objective of the present study was to investigate the genotoxic and antigenotoxic effects of BG extracted from the mushroom Agaricus brasiliensis (=Agaricus blazei Murrill ss. Heinemann). The mutagenic activity of BG was tested in single-cell gel electrophoresis assays with human peripheral lymphocytes. In addition, the protective effects against the cooked food mutagen 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2) and (+/-)-anti-B[a]P-7,8-dihydrodiol-9,10-epoxide (BPDE), which is the main metabolite of B[a]P, and against ROS (H(2)O(2))-induced DNA damage, were studied. The results showed that the compound itself was devoid of mutagenic activity, and that a significant dose-dependent protective effect against damage induced by hydrogen peroxide and Trp-P-2 occurred in the dose range 20-80 microg/ml. To investigate the prevention of Trp-P-2-induced DNA damage, a binding assay was carried out to determine whether BG inactivates the amine via direct binding. Since no such interactions were observed, it is likely that BG interacts with enzymes involved in the metabolism of the amine.