BackgroundTargeted delivery of gene therapy vectors to the mouse respiratory tract is often performed via intranasal or intratracheal administration; however, there can be a great deal of variability between these methods, which could potentially influence experimental results. Improving the accuracy and precision of lung delivery will not only reduce the number of animals required to detect statistically significant differences, but may reduce the variability of studies from different laboratories.ResultsHere we evaluated three different methods of adeno-associated virus (AAV) vector administration to the respiratory tract in mice (intranasal, intubation, and intratracheal injection) and discuss the advantages, challenges, and shortcomings of each. We also present a modified-intranasal delivery technique that is superior to passive administration of vector into the nares of anesthetized supine animals. Transgene expression was consistently visible in the nasal cavity, trachea, and proximal to middle aspect of all lung lobes for all four methods, whereas transgene expression was consistently observed in the most distal aspect of lung lobes only with the intubation and intratracheal injection techniques. AAV vector genome copy numbers in the lung were approximately four-fold lower in mice that received vector via intranasal administration in comparison to the other three methods of vector delivery. The modified intranasal, intubation and intratracheal injection methods of vector administration did not yield statistical differences in AAV vector genome copy numbers in the lung. With regard to reproducibility of vector distribution within and between animals, the modified-intranasal technique was superior.ConclusionOur results show that mode of AAV vector administration to the murine respiratory tract should be selected based on desired target site and skill of the researcher, and that appropriate technique selection may greatly influence experimental outcomes.Electronic supplementary materialThe online version of this article (doi:10.1186/s12896-017-0365-2) contains supplementary material, which is available to authorized users.

The double-stranded DNA genome of Choristoneura fumiferana nucleopolyhedrovirus (CfMNPV) was sequenced and analysed in the context of other group I nucleopolyhedroviruses (NPVs). The genome consists of 129 593 bp with a G+C content of 50?1 mol%. A total of 146 open reading frames (ORFs) of greater than 150 bp, and with no or minimal overlap were identified. In addition, five homologous regions were identified containing 7-10 repeats of a 36 bp imperfect palindromic core. Comparison with other completely sequenced baculovirus genomes revealed that 139 of the CfMNPV ORFs have homologues in at least one other baculovirus and seven ORFs are unique to CfMNPV. Of the 117 CfMNPV ORFs common to all group I NPVs, 12 are exclusive to group I NPVs. Overall, CfMNPV is most similar to Orgyia pseudotsugata MNPV based on gene content, arrangement and overall amino acid identity. Unlike other group I baculoviruses, however, CfMNPV encodes a viral enhancing factor (vef) and has two copies of p26. The GenBank/EMBL/DDBJ accession number of the complete genome sequence of CfMNPV reported in this paper is AF512031.

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The morbidity of measles shows a seasonal variation, with an increase in the first months of the year in temperate zones. Four-weeks morbidity data for England and Wales show an increase of measles over the period December-June and a decreasing morbidity during August-October (Fig. 1).These fluctuations might depend on at least three factors: variation in susceptibility of the host, virulence of the virus and (in airborne infectious diseases) virus survival in air.The influence of relative humidity (RH), temperature and artificial light on the survival of measles virus in air was examined.Virus (Edmonston strain) was aerosolized within five seconds in a conditioned room of 4 m a and droplet nuclei with an average diameter of 59 were obtained. Air samples were regularly taken with capillary impingers and the surviving virus was estimated by titration of the collection fluid by the plaque-count method (PFU/ml) on human amnion cells (strain U, Doorschodt). Virus recovery, one minute after spraying, was generally more than 70% at low RH and never less than 23% at high RH. In all experiments virus decay followed a logarithmic course (Fig. 2). The slope of the straight lines, expressed in K --A log N t At can be taken as a measure of the decay rate and was calculated for every experiment. At 20 ~ Celsius and low RH, measles virus survives well (K=--0,003) but virus decay increases quickly in the range from 40--70% RH (K= --0,056) (Fig. 3). When plotting log K against RH,

Purpose Selenium is an essential trace element that supports animal health through the antioxidant defense system by protecting cells from oxidative-related damage. Using inorganic selenium species, such as sodium selenite (Na Sel), as a food supplement is cost-effective; however, its limitation as a nutritional supplement is its cytotoxicity. One strategy to mitigate this problem is by delivering inorganic selenium using a nanoparticle delivery system (SeNP). Methods Rainbow trout intestinal epithelial cells, bovine turbinate cells and bovine intestinal myofibroblasts were treated with soluble Na Sel or SeNPs. Two SeNP formulations were tested; SeNP-Ionic where inorganic selenium was ionically bound to cationic phytoglycogen (PhG) NPs, and SeNP-Covalent, where inorganic selenium was covalently bound to PhG NPs. Selenium-induced cytotoxicity along with selenium bioavailability were measured. Results SeNPs (SeNP-Ionic or SeNP-Covalent) substantially reduced cytotoxicity in all cell types examined compared to similar doses of soluble inorganic selenium. The SeNP formulations did not affect selenium bioavailability, as selenium-induced glutathione peroxidase (GPx) activity and GPx1 transcript levels were similarly elevated whether cells were treated with soluble Na Sel or SeNPs. This was the case for all three cell types tested. Conclusion Nanoparticle-assisted inorganic selenium delivery, which demonstrated equal bioavailability without causing deleterious cytotoxic side effects, has potential applications for safely supplementing animal diets with inorganic selenium at what are usually toxic doses.