New neurons follow the flow of cerebrospinal fluid in the adult brain

In the adult brain, neuroblasts born in the subventricular zone migrate from the walls of the lateral ventricles to the olfactory bulb. How do these cells orient over such a long distance and through complex territories? Here we show that neuroblast migration parallels cerebrospinal fluid (CSF) flow. Beating of ependymal cilia is required for normal CSF flow, concentration gradient formation of CSF guidance molecules, and directional migration of neuroblasts. Results suggest that polarized epithelial cells contribute important vectorial information for guidance of young, migrating neurons.     

Evaluation of modified vaccinia virus Ankara expressing VP2 protein of infectious bursal disease virus as an immunogen in chickens

A recombinant modified vaccinia Ankara (MVA) virus expressing mature viral protein 2 (VP2) of the infectious bursal disease virus (IBDV) was constructed to develop MVA-based vaccines for poultry. We demonstrated that this recombinant virus was able to induce a specific immune response by observing the production of anti-IBDV-seroneutralizing antibodies in specific pathogen-free chickens. Besides, as the epitopes of VP2 responsible to induce IBDV-neutralizing antibodies are discontinuous, our results suggest that VP2 protein expressed from MVA-VP2 maintained the correct conformational structure. To our knowledge, this is the first report on the usefulness of MVA-based vectors for developing recombinant vaccines for poultry.     

Seroprevalence of Toxoplasma gondii and Neospora caninum in feral cats (Felis silvestris catus) in Majorca, Balearic Islands, Spain

Cryptosporidium spp. are common intestinal protozoan parasites that infect a wide range of hosts, including humans and livestock, worldwide. The objective of this study was to determine the prevalence of Cryptosporidium spp. in dairy calves in Prince Edward Island, Canada, and the potential for transmission of this parasite between dairy calves and humans. Fecal samples were collected from 183 dairy calves from 11 farms in Prince Edward Island. The prevalence of Cryptosporidium spp. infections in these animals was determined by examining for the presence of oocysts in the fecal samples, using immunofluorescence microscopy. Molecular characterization was done using a nested-PCR protocol to amplify fragments of the Cryptosporidium heat-shock protein 70 gene, followed by DNA sequencing. Ten calves (6.2%), representing 4 out of 11 farms tested, were positive for Cryptosporidium spp. DNA sequence analysis on five PCR positive samples demonstrated that Cryptosporidium parvum was the only species present in the calves tested, suggesting that there is a potential risk of zoonotic transmission between dairy calves and humans in this region.     

Detection of Leishmania infantum in captive wolves from Southwestern Europe

The aim of the present study was to determine the prevalence of Leishmania infantum infection in a wild reservoir host (Canis lupus) throughout an endemic area for the disease (Southern Europe). For that reason, the serum and peripheral blood samples of 33 captive wolves from the European Breeding of Endangered Species Programme (EEP) were analyzed using the enzyme-linked immunosorbent assay (ELISA) and real-time quantitative PCR (qPCR). L. infantum was detected in three samples from Central Portugal and Central and Northern Spain. Even though L. infantum infection in positive samples was low, surveillance of zoonotic leishmaniosis in this population is recommended as the parasite load could be higher in other tissues due to parasite tropism and most of the EEP institutions studied are located in endemic areas for canine leishmaniosis in Europe.     

Salmon cells SHK‐1 internalize infectious pancreatic necrosis virus by macropinocytosis

We have previously shown that infectious pancreatic necrosis virus (IPNV) enters the embryo cell line CHSE‐214 by macropinocytosis. In this study, we have extended our investigation into SHK‐1 cells, a macrophage‐like cell line derived from the head kidney of Atlantic salmon, the most economically important host of IPNV. We show that IPNV infection stimulated fluid uptake in SHK‐1 cells above the constitutive macropinocytosis level. In addition, upon infection of SHK‐1 cells, IPNV produced several changes in actin dynamics, such as protrusions and ruffles, which are important features of macropinocytosis. We also observed that the Na+/H+ pump inhibitor EIPA blocked IPNV infection. On the other hand, IPNV entry was independent of clathrin, a possibility that could not be ruled out in CHSE 214 cells. In order to determine the possible role of accessory factors on the macropinocytic process, we tested several inhibitors that affect components of transduction pathways. While pharmacological intervention of PKI3, PAK‐1 and Rac1 did not affect IPNV infection, inhibition of Ras and Rho GTPases as well as Cdc42 resulted in a partial decrease in IPNV infection. Further studies will be required to determine the signalling pathway involved in the macropinocytosis‐mediated entry of IPNV into its target cells.     

Fine‐scale population structure and connectivity of bottlenose dolphins,Tursiops truncatus,in European waters and implications for conservation

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