Rotavirus detection and isolation from chickens with or without symptoms

Rotaviruses have been identified as one of the main etiological agents of diarrhea and enteritis in mammals, including humans, and in avian species. Few studies have been published about enteric viruses in Brazilian poultry, including those related to rotavirus infection. Such studies demonstrate significant occurrence and the importance of enteric viruses in poultry presenting intestinal problems. Enteric viruses are the primary cause of injuries to the gut, allowing other agents, especially bacteria, to attach, to penetrate, and to replicate in the enteric tissue, leading to further damage. The aim of the present study was to detect rotavirus in the intestinal contents of layers and broilers by polyacrylamide gel electrophoresis (PAGE) and virus isolation in MA-104 cell culture. A total of 45.3% of all samples were positive to rotavirus; rotavirus frequencies were 48.7% in samples from flocks with diarrhea, 46.4% in flocks with delayed growth, and 30% in asymptomatic flocks. It was possible to isolate rotavirus in MA-104 cells from the nine rotavirus-positive randomly chosen samples. These results indicate that rotavirus may have an important role in pathogenesis of enteric disease

Statistical analysis of nanoparticle dosing in a dynamic cellular system

The delivery of nanoparticles into cells is important in therapeutic applications1, 2, 3 and in nanotoxicology4. Nanoparticles are generally targeted to receptors on the surfaces of cells and internalized into endosomes by endocytosis5, 6, 7, 8, 9, but the kinetics of the process and the way in which cell division redistributes the particles remain unclear. Here we show that the chance of success or failure of nanoparticle uptake and inheritance is random. Statistical analysis of nanoparticle-loaded endosomes indicates that particle capture is described by an over-dispersed Poisson probability distribution that is consistent with heterogeneous adsorption and internalization. Partitioning of nanoparticles in cell division is random and asymmetric, following a binomial distribution with mean probability of 0.52–0.72. These results show that cellular targeting of nanoparticles is inherently imprecise due to the randomness of nature at the molecular scale, and the statistical framework offers a way to predict nanoparticle dosage for therapy and for the study of nanotoxins

Investigation of Enteric Viruses in the Feces of Neotropical Migratory Birds Captured on the Coast of the State of Pará, Brazil

Made available in DSpace on 2018-12-11T16:53:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-01-01. Added 1 bitstream(s) on 2019-10-09T18:29:42Z : No. of bitstreams: 1 S1516-635X2018000100161.pdf: 376041 bytes, checksum: 32723ae502ce34e68b81829514936c67 (MD5)Migratory birds can become long-distance vectors for a wide range of microorganisms and can cause human disease, being the Brazilian coast a gateway for northern migratory birds. These animals are considered natural reservoirs of different viruses that cause important diseases, being relevant research of viral pathogens in migratory birds to epidemiology surveillance. The objective of the study was to investigate the presence of avian rotavirus (AvRV), avian reovirus (ARV) and picobirnavirus (PBV) in Neotropical migratory birds captured on the coast of Brazil. A total of 23 individual fecal samples of the migratory birds species Calidris pusilla (20 birds), Numenius phaeopus (1 bird) and Charadrius semipalmatus (2 birds) were collected. Fecal suspensions were prepared from the collected samples for subsequent extraction of double-stranded RNA (dsRNA), which was subjected to polyacrylamide gel electrophoresis (PAGE) and reverse transcription polymerase chain reaction (RT-PCR). The electrophoretic profiles were not detected by PAGE, and the amplification for the studied viruses PBV, ARV and AvRV (specie D, gene VP6 and NSP4) were negative. Positivity for AvRVD, VP7 gene was of 4.35% (1/23) for the migratory bird Calidris pusilla. After sequencing and building the tree of phylogenetic relationships avian Rotavirus Group D identified in this study was phylogenetically related and grouped into one branch, together to previously reported AvRVD from Brazil in chicken flocks with 99.8% nucleotide and 100% amino acid similarities.Laboratório de Zoonoses Faculdade de Medicina Veterinária Universidade Federal do Pará, Campus Castanhal, Rodovia BR-316 Km 62 s/n, SaudadeInstituto Evandro Chagas (IEC), BR-316 Km 7 s/n, Distrito de LevilândiaLaboratório Nacional de Agricultura (Lana-gro/PA) Ministério da Agricultura Pecuária e Abastecimento (MAPA), Av. Almirante Barroso1234, Distrito de MarcoUniversidade Federal Rural da Amazônia (UFRA), Av. Presidente Tancredo Neves 2501Universidade Estadual Paulista (UNESP), Distrito de Rubião Jr. S/NUniversidade Estadual Paulista (UNESP), Distrito de Rubião Jr. S/