Evaluation of the antiviral effects of aqueous extracts of red and yellow onions (Allium Cepa) against avian influenza virus subtype H9N2

Avian influenza virus subtype H9N2 causes important economic losses in industrial poultry worldwide. Biosecurity and vaccination have not completely prevented the outbreak of avian influenza virus subtype H9N2 in poultry, and there are no appropriate medicines available. Onion is one of the plants used from the ancient times both as food and medicine. The purpose of this study was to evaluate the antiviral effects of aqueous extract of red and yellow onion against avian influenza virus subtype H9N2. First, a study was performed to evaluate the toxic effects of the extracts on the embryonated chicken eggs. For antiviral evaluation, three mixtures were prepared: mixture of the virus and the red onion extract, mixture of the virus and the yellow onion extract, and mixture of the virus and PBS, as a control group. The mixtures were separately inoculated to the chorioallantoic sac of the embryonated eggs after 2, 8 and 24 hours incubation at room temperature. Mortality rate and hemagglutination assay titers were recorded. The results indicated that the red onion extract decreases mortality of the embryos and the yellow onion extract increases the life of the embryos, and both of the extracts decrease HA titers. In conclusion, it seems that both extracts especially aqueous extract of the red onion not only destroys the avian influenza virus subtype H9N2, but also they probably decrease the propagation of the virus in the embryonated chicken eggs

Sequencing and In Silico Multi-aspect Analysis of S1 Glycoprotein in 793/B Serotype of Infectious Bronchitis Virus Isolated From Iran in 2003 and 2011

Infectious bronchitis (IB) is an acute, highly contagious, and economically important viral disease of chickens. The S1 subunit from Spike (S) protein plays the major role in protective immunity and is involved in the host-virus interactions, as well as infectious bronchitis virus (IBV) serotyping. Aim of the present study was multi-aspect analysis of the molecular and immunological features of 5' part belonging to the S1 glycoprotein sequence of Iranian 793/B IBV strain isolates. This might ideally help in characterization, prevention, and vaccine development. The tissue samples were prepared, followed by virus isolation, reverse transcription polymerase chain reaction and restriction fragment length polymorphism analysis. In addition, sequencing and registration of the sequences in the National Center for Biotechnology Information were performed. Moreover, 12 sequences were retrieved from Fars province, Iran. The next steps included evaluation of conservation/variability along the sequences, phylogenetic analysis, estimation of the average evolutionary divergence over all the sequence pairs, predicting the phosphorylation/N-glycosylation/palmitoylation sites, and the final analysis of antigenicity. The findings of alignment, entropy plot, and pairwise similarity analysis revealed 17 hypervariable regions. The isolates belonging to Tehran were clustered in phylogenetic tree, and the most similar isolates to them were ADW11182 and ADW11183. Location of some of the N-glycosylation/phosphorylation/palmitoylation points indicated that these sites were conserved among the isolates. Furthermore, the frequency of epitopes and their scores reflect the high immunogenicity of S1 protein in 793/B serotype. Analysis of the primary and secondary structures demonstrated that their parameters had variable values and were different regarding the number and location of α-helix, β-strand, and coils. According to our findings, the Iranian isolates of 793/B serotype change their molecular characteristics during time and in different geographical regions. These alterations might account for failure in prevention programs and differences in virulence and pathogenicity

An inactivated vaccine to control the current H9N2 low pathogenic avian influenza in Korea

The H9N2 subtype low pathogenic avian influenza is one of the most prevalent avian diseases worldwide, and was first documented in 1996 in Korea. This disease caused serious economic loss in Korea's poultry industry

Numerical Study of Cavitating Flow Over a Hydrofoil

RÉSUMÉ En raison de la complexité du champ d'écoulement cavitant et des fluctuations soudaines de pression autour des aubes des machines hydrauliques, la modélisation de la cavitation est un problème très difficile, et comme elle a de nombreux effets néfastes dans de nombreuses industries telles que l'industrie hydraulique, cela a été un sujet de recherche très actif au cours des dernières décennies. Étant donné que les variations de turbulence près d’un profil hydraulique peuvent entraîner une sous-estimation dans la prédiction de la pression locale, des pressions inférieures à la pression de saturation peuvent être prédites. Par conséquent, le choix du bon modèle de turbulence qui modélise la viscosité de manière appropriée est d'une grande importance. La recherche actuelle est effectuée à l'aide du solveur commercial ANSYS-Fluent 16.1 et elle est consacrée à la modélisation des écoulements cavitants à différents nombres de Thoma (σ) autour d'un profil NACA66. À cet égard, dans le chapitre 3, le modèle de cavitation Zwart-Gerber-Belamri couplé à l'approche de modélisation multiphase mixte ainsi que le modèle de turbulence standard k−ε (SKE) est appliqué, et la précision des prédictions numériques effectuées est étudiée. Ensuite, l'effet de certains autres paramètres sur la simulation en régime permanent tels que la densité du maillage, les critères de convergence, divers modèles de turbulence, à savoir la turbulence SKE et SST k - ω, et la taille du pas de temps est étudié, et les résultats obtenus sont comparés avec des résultats expérimentaux. L'objectif de cette recherche est de développer une configuration numérique pour laquelle certaines caractéristiques qualitatives et quantitatives de l'écoulement du fluide cavitant telles que la mesure du coefficient de pression (Cp), les fluctuations de pression soudaines et leurs fréquences, l'initiation de la cavitation, la croissance et son effondrement sur le profil NACA66 sont prédits. En accord avec les résultats expérimentaux et sur la base des prédictions de Cp autour du profil, la cavitation à σ = 1.25 était instable, et la cavitation associée à un écoulement cavitant avec σ = 1.41, 1.34 et 1.30 est rapportée comme stable et les longueurs de cavitation ont été prédites avec une précision décente variant de 5% à 14% d'erreur. De plus, les caractéristiques instables de la cavitation autour du profil NACA66 connue comme de la cavitation en nuages sont étudiées dans la recherche actuelle. Dans le chapitre 4, en effectuant des simulations transitoires, les prédictions de fréquences associées aux fluctuations soudaines de pression dans les écoulements cavitants à différents nombres de cavitation, à savoir σ = 1.41,1.34, et 1.30, sont également démontrées en bon accord avec les résultats expérimentaux avec seulement 3,5%, 6,3 % et 10,0 % d'erreur, respectivement. Il convient de noter qu'un maillage généré à partir de près d'un million de nœuds ainsi que la taille de pas de temps la plus fine possible, soit 0,00002 (s), est utilisé pour exécuter les simulations, et le modèle de turbulence SKE et la cavitation Kubota sont utilisés pour les calculs numériques. De plus, en accord avec les résultats expérimentaux, les résultats CFD ont confirmé que la fréquence mentionnée diminue à mesure que la longueur de cavitation augmente. ---------- ABSTRACT Due to the complexity of cavitating flow field and sudden pressure fluctuations around the blades of hydraulic machinery, cavitation modeling is a very challenging problem, and since it has many detrimental effects on many industries such as the hydraulic industry, it has been a very interesting topic for researchers in the last decades. Since turbulence variations near hydrofoil can result in under prediction of local pressure, pressures lower than the saturation pressure might be predicted. Hence, choosing the right turbulence model which models viscosity appropriately, is of great importance. The objective of this research is to develop a numerical setup by which some qualitive and quantitative characteristics of the cavitating fluid flow such as pressure coefficient (Cp) measurement, sudden pressure fluctuations and the frequencies associated with the highestpressure variations, cavitation initiation, growth, and collapse over the NACA66 hydrofoil are predicted. In agreement with the experimental results and based on the Cp predictions around the hydrofoil, the cavitation at σ = 1.25 was unstable, and the cavitation associated with a cavitating flow σ = 1.41, 1.34 and 1.30 are reported to be stable and the cavitation lengths were predicted with a decent precision varying from 5% to 14% error. Furthermore, the unsteady characteristics of cavitation around the NACA66 hydrofoil experiencing cloud cavitation is studied in the current research. The current research is performed using the ANSYS-Fluent 16.1 commercial solver and it is devoted to model cavitating flows at different Thoma numbers (σ) around a NACA66 hydrofoil. In this regard, in chapter 3, the Zwart-Gerber-Belamri cavitation model coupled with the mixed multiphase modeling approach as well as the standard k - ε (SKE) turbulence model is applied, and the precision of the performed numerical predictions is investigated using the named models. Then, the effect of some other parameters on the steady-state simulation such as mesh density, convergence criteria, various turbulence models, namely SKE and SST k - ω turbulence, and time-step size is studied, and the obtained results are compared with the experimental results. In chapter 4, by performing transient simulations, frequency predictions associated with the sudden pressure fluctuations in the cavitating flows at different cavitation numbers, namely σ = 1.41, 1.34, and 1.30, are also demonstrated good agreement with the experimental results with only 3.5%, 6.3%, and 10.0% error, respectively. It should be noted that a mesh generated from near one million nodes as well as the finest feasible time-step size meaning 0.00002 (s), is used to run the simulations, and the SKE turbulence model and Kubota cavitation are employed for the numerical calculations. Furthermore, in agreement with the experimental results, the CFD results confirmed that the mentioned frequency reduces as cavitation length increases

Detection of Avian Influenza Virus of H9 Subtype in the Faeces of Experimentally and Naturally Infected Chickens by Reverse Transcription-Polymerase Chain Reaction

Avian Influenza (AI) is a viral, highly contagious disease of domestic and wild birds. In an avian diagnostic laboratory, it is essential to have methods for rapid detection of respiratory viruses. In the present study, cloacal swabs collected from chickens experimentally and naturally infected with mild pathogenicity AI virus subtype H9, used in a reverse transcription-polymerase chain reaction (RTPCR) assay for detection of AI. On cloacal swabs collected from experimentally infected chickens, AI virus was detected most frequently between days 3 and 7 post infection (p.i.) and the relative sensitivity, specificity, correlation rate, positive predictive value and negative predictive value of the RT-PCR compared to virus isolation (VI) assay were 84%, 80%, 82%, 83% and 81%, respectively. On pooled cloacal swabs collected from flocks suspected of AI, these results were 96%, 100%, 97%, 83% and 100%, respectively. The results proved that the RT-PCR assay could be a reliable and rapid alternative to VI assay for detection of AI virus subtype H9 in faecal specimens

Isolation of H9N2 Subtype of Avian Influenza Viruses during an Outbreak

ABSTRACT Avian influenza is an important disease of poultry with the potential to cause major epidemics resulting in significant economic losses. The presence of avian influenza viruses (AIV) in chickens in Iran has not been previously reported. An avian influenza outbreak in broiler, layer and breeder farms occurred during a very hot summer in July 1998. Three AIV isolates designated as 101, 102 and 103 were isolated from lung, tracheal cloacal samples of layer, breeder and broiler chickens, in embryonated chicken eggs. The presence of AIV in allantoic fluid cells was confirmed by indirect immunofluorescence assay using a monoclonal antibody against type A nucleoprotein. The viruses were further classified as H9N2 subtype in hemagglutination inhibition and neuraminidase inhibition tests using 15 hemagglutinin and 9 neuraminidase subtype specific antisera. The pathogenicity of AIV isolates was carried out in 4-6-wk-old chickens. No birds died within 10 days after inoculation of infectious allantoic fluids. Therefore, the representative Iranian layer, breeder and broiler AIV strains were classified as non-highly pathogenic avian influenza viruse pathotype. Isolation of the same subtype and pathotype of AIV from different flocks suggested that the H9N2 AIV subtype is a common pathogen involved in poultry industry respiratory disease outbreak. Iran. Biomed. J. 6 (1): 13-17, 200

Isolation of H9N2 Subtype of Avian Influenza Viruses during an Outbreak

ABSTRACT Avian influenza is an important disease of poultry with the potential to cause major epidemics resulting in significant economic losses. The presence of avian influenza viruses (AIV) in chickens in Iran has not been previously reported. An avian influenza outbreak in broiler, layer and breeder farms occurred during a very hot summer in July 1998. Three AIV isolates designated as 101, 102 and 103 were isolated from lung, tracheal cloacal samples of layer, breeder and broiler chickens, in embryonated chicken eggs. The presence of AIV in allantoic fluid cells was confirmed by indirect immunofluorescence assay using a monoclonal antibody against type A nucleoprotein. The viruses were further classified as H9N2 subtype in hemagglutination inhibition and neuraminidase inhibition tests using 15 hemagglutinin and 9 neuraminidase subtype specific antisera. The pathogenicity of AIV isolates was carried out in 4-6-wk-old chickens. No birds died within 10 days after inoculation of infectious allantoic fluids. Therefore, the representative Iranian layer, breeder and broiler AIV strains were classified as non-highly pathogenic avian influenza viruses pathotype. Isolation of the same subtype and pathotype of AIV from different flocks suggested that the H9N2 AIV subtype is a common pathogen involved in poultry industry respiratory disease outbreak. Iran. Biomed. J. 6 (1): 13-17, 200