Structural and H₂S Sensing Properties of Copper Ferrite Nanoparticles Prepared Through Hydrothermal Method.

In this paper, we report the H₂S sensing properties of partially inverse copper ferrite (CuFe₂O₄) nanoparticles with sizes ranging from 16 nm to few hundreds of nanometers prepared through hydrothermal method. Effects of annealing temperature on the particle size, microstructure and gas-sensing properties of spinel ferrite were studied through scanning electron microscopy, synchrotron X-ray powder diffraction and resistance measurement. Electrical conduction mechanism is discussed based on the cation distribution in the lattice and resistance contribution from the grain boundaries.

Consumption of lysozyme-rich milk can alter microbial fecal populations.

Human milk contains antimicrobial factors such as lysozyme and lactoferrin that are thought to contribute to the development of an intestinal microbiota beneficial to host health. However, these factors are lacking in the milk of dairy animals. Here we report the establishment of an animal model to allow the dissection of the role of milk components in gut microbiota modulation and subsequent changes in overall and intestinal health.

Prevalence of low pathogenicity avian influenza virus during 2005 in two U.S. live bird market systems.

Oropharyngeal and cloacal swabs were collected from poultry sold in two live bird market (LBM) systems to estimate the prevalence of low pathogenicity avian influenza virus (LPAIV) shedding during the summer and fall of 2005. Random sampling was conducted in three LBMs in Minnesota where 50 birds were sampled twice weekly for 4 wk, and in three LBMs in a California marketing system. A stratified systematic sampling method was used to collect samples from Southern California LBMs, where LPAIV was detected during routine surveillance.

High-throughput neuraminidase substrate specificity study of human and avian influenza A viruses.

Despite the importance of neuraminidase (NA) activity in effective infection by influenza A viruses, limited information exists about the differences of substrate preferences of viral neuraminidases from different hosts or from different strains. Using a high-throughput screening format and a library of twenty α2-3- or α2-6-linked para-nitrophenol-tagged sialylgalactosides, substrate specificity of NAs on thirty-seven strains of human and avian influenza A viruses was studied using intact viral particles. Neuraminidases of all viruses tested cleaved both α2-3- and α2-6-linked sialosides but preferred α2-3-linked ones and the activity was dependent on the terminal sialic acid structure.

Influenza A viruses in wild birds of the Pacific flyway, 2005-2008.

Avian influenza viruses (AIVs) pose a significant threat to public health, and viral subtypes circulating in natural avian reservoirs can contribute to the emergence of pathogenic influenza viruses in humans. We investigated the prevalence and distribution of AIVs in 8826 migratory and resident wild birds in North America along the Pacific flyway, which is a major north-south migration pathway that overlaps with four other flyways in Alaska providing opportunities for mixing of Eurasian and American origin influenza viruses. Overall, the prevalence of AIVs was low (1%) among the wide range of avian species tested, but we detected AIVs in 69 hunter-harvested waterfowl (Anseriformes) sampled at a national wildlife refuge in California from October 2007 to January 2008.

Roles of the ERK MAPK in the regulation of proinflammatory and apoptotic responses in chicken macrophages infected with H9N2 avian influenza virus.

The mitogen-activated protein kinase (MAPK) family is responsible for important signalling pathways which regulate cell activation, differentiation, apoptosis and immune responses. Studies have shown that influenza virus infection activates MAPK family members in mammals. While the extracellular signal-regulated kinase (ERK)1/2 is important for virus replication, activation of p38 controls the expression of RANTES, interleukin (IL)-8 and tumour necrosis factor (TNF)-alpha.

Adaptation and transmission of a duck-origin avian influenza virus in poultry species.

A duck-origin avian influenza virus (AIV) was used to study viral adaptation and transmission patterns in chickens (Gallus gallus domesticus) and Pekin ducks (Anas platyrhynchos domesticus). Inoculated birds were housed with naïve birds of the same species and all birds were monitored for infection. The inoculating duck virus was transmitted effectively by contact in both species.

Modulation of the immune responses in chickens by low-pathogenicity avian influenza virus H9N2.

Most low-pathogenicity avian influenza (LPAI) viruses cause no or mild disease in avian species. Little is known about the mechanisms of host defence and the immune responses of avian influenza-infected birds. This study showed that chicken macrophages are susceptible to infection with LPAI H9N2 and H6N2 viruses and that infection led to apoptosis.