Coronaviruses Detected in Brazilian Wild Birds Reveal Close Evolutionary Relationships with Beta- and Deltacoronaviruses Isolated From Mammals

This study showed that the most of the coronaviruses (CoVs) detected in Brazilian wild birds clustered with the mouse hepatitis virus A59 strain, belonging to the BetaCoV group. Furthermore, CoV detected in two different bird species, Amazona vinacea and Brotogeris tirica, clustered with a CoV isolated from Sparrow (SpaCoV HKU17) belonging to a monophyletic group related with the CoVs isolated from swines (PorCoV HKU15), both belonging to the DeltaCoV genus, previously unreported in South America. Considering the risk of inter-species host switching and further adaptation to new hosts, detection in bird species of CoVs closely related to mammal CoVs should warn for the potential emergence of new threatening viruses.Fundação de Amparo à Pesquisa do Estado de São Paulo (Grants 2013/03922-6 and 2011/50919-5

Detection Of Brazilian Bovine Respiratory Syncytial Virus Strain By A Reverse Transcriptase-nested-polymerase Chain Reaction In Experimentally Infected Calves.

A reverse transcriptase (RT)-nested-polymerase chain reaction (PCR) was standardised to detect bovine respiratory syncytial virus (BRSV), using a Brazilian isolate, in three experimentally infected calves. This followed initial tests in infected chicken embryo related (CER) cells. One animal had lesions, characterized by interstitial multifocal pneumonia, severe interstitial and subpleural emphysema, and lung consolidated areas. Lung and tracheal tissues collected 6 days after infection were analysed by RT-nested-PCR. Primers, specific for the BRSV G and F glycoproteins genes, yielded amplification fragments of 371 and 481 bp, respectively, from the RNA of the cell-propagated virus. Using RNA extracted from organs of infected calves, RT-nested-PCR amplified the fragment of the G gene in all tracheal samples, but in only two of three lung samples analysed. These results suggest that RT-nested-PCR could be a promising assay for diagnosis and epidemiological analysis of BRSV in Brazil.105131-

Epidemiological and genetic characteristics associated with the severity of acute viral bronchiolitis by respiratory syncytial virus

OBJECTIVE: to assess the epidemiological and genetic factors associated with severity of acute viral bronchiolitis (AVB) by respiratory syncytial virus (RSV). DATA SOURCE: the key words ''bronchiolitis'', ''risk factor'', ''genetics'' and ''respiratory syn-cytial virus'', and all combinations among them were used to perform a search in the PubMed,SciELO, and Lilacs databases, of articles published after the year 2000 that included individualsyounger than 2 years of age. DATA SYNTHESIS: a total of 1,259 articles were found, and their respective summaries were read. Of these, 81 were selected, which assessed risk factors for the severity of AVB, and were read in full; the 60 most relevant studies were included. The epidemiologic factors associated with AVB severity by RSV were prematurity, passive smoking, young age, lack of breastfeeding, chronic lung disease, congenital heart disease, male gender, ethnicity, viral coinfection, low weight at admission, maternal smoking during pregnancy, atopic dermatitis, mechanical ventilation in the neonatal period, maternal history of atopy and/or asthma during pregnancy, season of birth, low socioeconomic status, Down syndrome, environmental pollution, living at an altitude > 2,500 meters above sea level, and cesarean section birth. Conversely, some children with severe AVB did not present any of these risk factors. In this regard, recent studies have verified the influence of genetic factors on the severity of AVB by RSV. Polymorphisms of the TLRs, RANTES, JUN, IFNA5, NOS2, CX3CR1, ILs, and VDR genes have been shown to be associated with more severe evolution of AVB by RSV. CONCLUSION: the severity of AVB by RSV is a phenomenon that depends on the varying degrees of interaction among epidemiological, environmental, and genetic variables.OBJETIVO: avaliar os fatores epidemiológicos e genéticos associados à gravidade da Bronquiolite Viral Aguda (BVA) pelo Vírus Sincicial Respiratório (VSR). FONTE DOS DADOS: foram utilizados descritores bronchiolitis, risk factor, genetics e respiratory syncytial virus e todas as combinações entre eles, nas bases de dados PubMed, SciELO e Lilacs publicados após o ano de 2000 e que incluíram indivíduos menores de dois anos de idade. SÍNTESE DOS DADOS: foram encontrados 1.259 artigos e lidos seus respectivos resumos. Destes foram selecionados 81 que avaliaram fatores de risco para a gravidade da BVA para leitura na íntegra, e foram incluídos os 60 estudos mais relevantes. Os fatores epidemiológicos associados com a gravidade da BVA pelo VSR foram: prematuridade, tabagismo passivo, baixa idade, ausência de aleitamento materno, doença pulmonar crônica, cardiopatia congênita, sexo masculino, etnia, coinfecção viral, baixo peso na admissão hospitalar, tabagismo materno na gestação, dermatite atópica, ventilação mecânica no período neonatal, antecedente materno de atopia e/ou asma na gestação, estação do nascimento, baixo nível socioeconômico, síndrome de Down, poluição ambiental, morar em altitude acima de 2.500 metros do nível do mar e parto cesariana. Em contrapartida, algumas crianças com BVA grave não apresentam nenhum desses fatores de risco. Neste sentido, estudos recentes têm verificado a influência de fatores genéticos relacionados à gravidade da BVA pelo VSR. Polimorfismos dos genes TLRs, RANTES, JUN, IFNA5, NOS2, CX3CR1, ILs e VDR têm-se mostrado associados com a evolução mais grave da BVA pelo VSR. CONCLUSÃO: a gravidade da BVA pelo VSR é um fenômeno dependente da interação entre variáveis epidemiológicas, ambientais e genéticas em seus diferentes graus de interação

Sequential extraction of bioactive compounds from melia azedarach L. in fixed bed extractor using CO2, ethanol and water

Melia azedarach L. is a plant with wide use in folk medicine since it contains many bioactive compounds ofinterest. The present study aimed to extract bioactive compounds from M. azedarach fruits by a sequentialprocess in fixed bed using various solvent mixtures. Extractions were performed at 50°C and 300 bar infour sequential steps using supercritical CO2(scCO2), scCO2/ethanol, pure ethanol, and ethanol/watermixture as solvents, respectively. The efficacy of the extraction process was evaluated by extraction yieldand kinetics, and analysis of extracts by: (1) thin layer chromatography (TLC), (2) phenolics content,(3) reduction of surface tension of water, (4) gas chromatography (GCMS), (5) electrospray ionizationmass spectrometry (ESIMS) and (6) antiviral activity. The overall extraction yield reached 45% andTLC analysis showed extracts with different composition. extract obtained from CO2/ethanol mixture(SCEE) exhibited the greatest ability to reduce surface tension of water from 72.4 mN m?1[1] of purewater to 26.9 mN m?1of an aqueous solution of 40 g L?1. The highest phenolics contents were observedin both the hydroalcoholic extract and scCO2/ethanolic extract. Volatile oils were not detected in thesupercritical extracts by GCMS. MS analyses identified the fatty acids: linoleic, palmitic and myristicacid in the supercritical extract (SCE), and the phenolics: caffeic acid and malic acid in the other extracts.In addition, SCE and SCEE extracts showed significant inhibition percentage against Herpes Simplex VirusType 1. The extraction process proposed in the present study produced extracts with significant potentialfor application in food and pharmaceutical industries.Melia azedarach L. is a plant with wide use in folk medicine since it contains many bioactive compounds of interest. The present study aimed to extract bioactive compounds from M. azedarach fruits by a sequential process in fixed bed using various solvent95355363FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO2012/20736-9131022/2012-1Bitencourt, R.G., Queiroga, C.L., Montanari Junior, I., Cabral, F.A., Fractionated extraction of saponins from Brazilian ginseng by sequential process using supercritical CO2, ethanol and water (2014) J. Supercritical Fluids, 92, pp. 272-281Al-Rubae, A.Y., The potential uses of Melia azedarach L. As pesticidal and medicinal plant, review (2009) American-Eurasian J. 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Tropical Biomedicine, 1, pp. 452-455Carpinella, M.C., Miranda, M., Almirón, W.R., Ferrayoli, C.G., Almeida, F.L., Palacios, S.M., In vitro pediculicidal and ovicidal activity of an extract and oil from fruits of Melia azedarach L (2007) J. American Academy of Dermatology, 56, pp. 250-256McKenna, M.M., Abou-Fakhr Hammad, E.M., Farran, M.T., Effect of Melia azedarach (Sapindales: Meliaceae) fruit extracts on Citrus Leafminer Phyllocnistis citrella (Lepidoptera: Gracillariidae) (2013) SpringerPlus, 2, pp. 144-150Scapinello, J., Ribeiros, M.L., Tomazelli, O., Jr., Chiaradia, L.A., Vladimir, J., Oliveira, J.D.M., Effects of supercritical CO2 extracts of Melia azedarach L. on the control of fall armyworm (Spodoptera frugiperda) (2014) J. Supercritical Fluids, 86, pp. 100-107Akihisa, T., Pan, X., Nakamura, Y., Kikuchi, T., Takahashi, N., Matsumoto, M., Ogihara, E., Tokuda, H., Limonoids from the fruits of Melia azedarach and their cytotoxic activities (2013) Phytochemistry, 89, pp. 59-70Yuan, C.M., Zhang, Y., Tang, G.H., Li, Y., He, H.P., Li, S.F., Hou, L., Hao, X.J., Cytotoxic limonoids from Melia azedarach (2013) Planta Medica, 79, pp. 163-168Aoudia, H., Oomah, B.D., Zaidi, F., Zaidi-Yahiaoui, R., Drover, J.C.G., Harrison, J.E., Phenolics, antioxidant and anti-inflammatory activities of Melia azedarach extracts (2013) International J. Applied Research in Natural Products, 6, pp. 19-29Matias, R., Sólon, S., Resende, U.M., Gomes, A., Koller, W.W., Melia azedarach, uso popular x estudos químico e farmacológico: Breve revisão (2002) Ensaios e Ciência, 6, pp. 91-121Yang, Y., Xiao, Y., Liu, B., Fang, X., Yang, W., Xu, J., Comparison of headspace solid-phase microextraction with conventional extraction for the analysis of the volatile components in Melia azedarach (2011) Talanta, 86, pp. 356-361Aoudia, H., Ntalli, N., Aissani, N., Yahiaoui-Zaidi, R., Caboni, P., Nematotoxic phenolic compounds from Melia azedarach against Meloidogyne incognita (2012) J. Agricultural and Food Chemistry, 60, pp. 11675-11680Orhan, I.E., Guner, E., Ozturk, N., Senol, F.S., Erdem, S.A., Kartal, M., Sener, B., Enzyme inhibitory and antioxidant activity of Melia azedarach L. Naturalized in Anatolia and its phenolic acid and fatty acid composition (2012) Industrial Crops and Products, 37, pp. 213-218Chiffelle, I.G., Huerta, A.F., Lizana, D.R., Physical and chemical characterization of Melia azedarach L. Fruit and leaf for use as botanical insecticide (2009) Chilean J. Agricultural Research, 69, pp. 38-45Seffrin, R.C.A.S., Corrêa Costa, E., Borges, L., Corralo Borges, V., Do Nascimento, P.C., Bastos Dequech, S.T., Sausen, C.D., Extratos aquosos de frutos verdes de Melia azedarach L. Var. Azedarach: Investigação da presença de cianeto e avaliação toxicológica (2011) Biotemas, 21, pp. 143-147Brunner, G., Supercritical fluids: Technology and application to food processing (2005) J. Food Engineering, 67, pp. 21-33Seabra, I.J., Braga, M.E.M., Batista, M.T., De Sousa, H.C., Effect of solvent (CO2/ethanol/H2O) on the fractionated enhanced solvent extraction of anthocyanins from elderberry pomace (2010) J. 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Detecção de metapneumovirus aviário subtipo A em aves silvestres no estado de São Paulo, Brasil

The present study investigated the circulation of avian metapneumovirus (aMPV) in wild birds in Brazil. To do so, 131 samples from 366 oropharyngeal or cloacal swabs collected from 18 species of birds were tested individually or in pools by RT-PCR. Samples detected by RT-PCR were selected for DNA sequencing. Thirteen (9.9%) samples were detected by the RT-PCR targeting the N gene and four out of 13 samples were sequenced. Sequencing results showed a high identity with the aMPV subtype A. Our results confirm the circulation of the aMPV subtype A in wild birds in Brazil even five years after its last detection393209213CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP443250/2014-6sem informação2015/11510-5O presente estudo investigou a circulação de metapneumovírus aviário em aves silvestres no Brasil. Para tanto, 131 amostras de 366 suabes orofaringeanos ou cloacais coletados de 18 espécies de aves foram testadas individualmente ou na forma de pools por RT-PCR. As amostras detectadas por RT-PCR foram selecionadas para sequenciamento. Treze (9,9%) das amostras foram detectadas por RT-PCR tendo o gene N como alvo; destas, quatro foram sequenciadas com sucesso. Resultados do sequenciamento mostraram alta identidade com o aMPV de subtipo A. Nossos resultados confirmam a circulação de aMPV subtipo A em aves silvestres no Brasil mesmo cinco anos após sua última detecçã

Metapneumovirus aviário subtipos A e B brasileiros: infecção experimental em frangos de corte e ef icácia vacinal

Santos M.B., Martini M.C., Ferreira H.L., Silva L.H.A., Fellipe P.A., Spilki F.R. & Arns C.W. 2012. Brazilian avian metapneumovirus subtypes A and B: experimental infection of broilers and evaluation of vaccine efficacy. Pesquisa Veterinaria Brasileira 32(12):1257-1262. Laboratorio de Virologia, Instituto de Biologia, Universidade Estadual de Campinas, Rua Monteiro Lobato s/n, Cx. Postal 6109, Campinas, SP 13083-970, Brazil. E-mail: [email protected] Avian metapneumovirus (aMPV) is a respiratory pathogen associated with the swollen head syndrome (SHS) in chickens. In Brazil, live aMPV vaccines are currently used, but subtypes A and, mainly subtype B (aMPV/A and aMPV/B) are still circulating. This study was conducted to characterize two Brazilian aMPV isolates (A and B subtypes) of chicken origin. A challenge trial to explore the replication ability of the Brazilian subtypes A and B in chickens was performed. Subsequently, virological protection provided from an aMPV/B vaccine against the same isolates was analyzed. Upon challenge experiment, it was shown by virus isolation and real time PCR that aMPV/B could be detected longer and in higher amounts than aMPV/A. For the protection study, 18 one-day-old chicks were vaccinated and challenged at 21 days of age. Using virus isolation and real time PCR, no aMPV/A was detected in the vaccinated chickens, whereas one vaccinated chicken challenged with the aMPV/B isolate was positive. The results showed that aMPV/B vaccine provided a complete heterologous virological protection, although homologous protection was not complete in one chicken. Although only one aMPV/B positive chicken was detected after homologous vaccination, replication in vaccinated animals might allow the emergence of escape mutants.O Metapneumovírus aviário (aMPV) é um patógeno respiratório associado à síndrome da cabeça inchada (SHS) em galinhas. Apesar de vacinas vivas contra o aMPV serem utilizadas no Brasil, os subtipos A e B (aMPV/A e aMPV/B) são ainda encontrados no país, com predominância do subtipo B. Este estudo foi conduzido com o intuito de estudar dois isolados brasileiros de aMPV (subtipos A e B) isolados de frango. Para isto, um desa io experimental em frangos foi conduzido com o intuito de explorar a capacidade de replicação dos subtipos A e B Brasileiros. Posteriormente, a protecção virológica conferida por uma vacina do subtipo B em pintos foi realizada com os mesmos isolados. Após o desa io experimental demonstrou-se, por isolamento viral e PCR em tempo real, que o isolado do subtipo B replicou por maior período de tempo e em quantidades maiores, em comparação com o subtipo A. Para o estudo de proteção, 18 pintos de um dia de idade foram vacinados e desa iados aos 21 dias. Usando isolamento viral e PCR em tempo real, em nenhuma ave vacinada e desa iada com aMPV/A foi detectado o vírus, ao passo que uma ave vacinada e desa iada com o aMPV/B foi positiva. Os resultados mostraram que a vacina do subtipo B forneceu protecção heteróloga completa, embora a protecção homóloga