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1.
Animals (Basel) ; 11(9)2021 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-34573707

RESUMEN

Duck hepatitis virus (DHV) is one of the commercially important diseases of ducklings worldwide. It is an acute and highly infectious disease of ducklings caused by three different serotypes (1-3) of duck hepatitis A virus (DHAV), and serotype 1 is the most common in poultry. To date, little is known about the prevalence and genetic characterisation of DHAV-1 in Egypt. In the current study, isolation and complete genomic analyses of DHAVs circulating in commercial duck farms in different Egyptian governorates were conducted. A total of eighteen samples were collected from six Egyptian governorates of 3-11 days old ducklings (Pekin and Mullard) with a history of nervous signs and high mortality rates. Five out of eighteen (5/18) samples were screened positive for the DHAV-1 based on the VP1 gene. These samples were individually used for virus isolation in embryonated duck embryos (EDE), followed by complete genome sequencing. Phylogenomic analyses showed that DHAV serotype I; genotype I were diversified into four different groups (1-4). Most of the recent circulating Egyptian DHAV strains are clustered within group 4, while isolates characterised within this study were clustered within group 1. Recombination analyses revealed that the emergence of a new recombinant virus-DHAV-1 strain Egypt-10/2019-through recombination. Likewise, the selective pressure analyses showed the existence, inside or near areas of the viral attachment or related functions, of positive scores highlighting the importance of natural selection and viral evolution mechanism at different protein domains. The findings of this study provide updated information on the epidemiological and genetic features of DHAV-1 strains and underscore the importance of DHAV surveillance as well as re-evaluation for currently used vaccines.

2.
Appl Opt ; 60(13): 3659-3667, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33983298

RESUMEN

This paper presents a new trend in biometric security systems, which is cancelable multi-biometrics. In general, traditional biometric systems depend on a single biometric for identification. These traditional systems are subject to different types of attacks. In addition, a biometric signature may be lost in hacking scenarios; for example, in the case of intrusion, biometric signatures can be stolen forever. To reduce the risk of losing biometric signatures, the trend of cancelable biometrics has evolved by using either deformed or encrypted versions of biometrics for verification. In this paper, several biometric traits for the same person are treated to obtain a single cancelable template. First, optical scanning holography (OSH) is applied during the acquisition of each biometric. The resulting outputs are then compressed simultaneously to generate a unified template based on the energy compaction property of the discrete cosine transform (DCT). Hence, the OSH is used in the proposed approach as a tool to generate deformed versions of human biometrics in order to get the unified biometric template through DCT compression. With this approach, we guarantee the possibility of using multiple biometrics of the same user to increase security, as well as privacy of the new biometric template through utilization of the OSH. Simulation results prove the robustness of the proposed cancelable multi-biometric approach in noisy environments.


Asunto(s)
Biometría/métodos , Seguridad Computacional , Compresión de Datos/métodos , Holografía/métodos , Simulación por Computador , Dermatoglifia , Mano , Humanos , Iris , Curva ROC
3.
Virus Genes ; 55(5): 720-725, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31372921

RESUMEN

Infectious bronchitis virus (IBV) affects both vaccinated and unvaccinated flocks worldwide, with a significant impact on the poultry industry. The aim of the present study is to characterize an emerging variant pathogenic IBV originating from field outbreaks in vaccinated Egyptian layer flock. Samples were collected from disease-suspected flock with a history of administration of live and inactivated IBV vaccines (Ma5 type). Virus propagation in embryonated chicken eggs (ECEs), after three successive passages, revealed typical IBV lesions such as curling and dwarfism. The reported isolate was identified by a real-time reverse transcriptase PCR assay targeting nucleocapsid (N) gene and, further characterized by full-length spike (S1) gene sequencing. Phylogenetic analysis revealed clustering of the isolated virus within 4/91 genotype of GI-13 lineage. Deduced amino acid sequences identity revealed 75-76% and 88-90% similarity with the currently used classic (H120, Ma5, and M41) and variant vaccine strains (4/91 and CR88) in Egypt, respectively. Recombination analysis gave an evidence for distinct patterns of origin for the studied isolate providing another example of intra-genotypic recombination among IBVs and the first example of recombination within the GI-13 lineage in the Egyptian field. The studied isolate (IBV/CK/EG/Fadllah-10/2019) emerged as a result of recombination between the variant group (Egy/var I genotype, GI-23 lineage) as a major parent and the CR88 variant vaccine strain (4/91 genotype, GI-13 lineage) as minor parent. Our data suggest that both mutation and recombination may be contributing to the emergence of IBV variants which ascertain the importance of disease monitoring in vaccinated flocks as well as re-appropriation for the current vaccine strategies.


Asunto(s)
Infecciones por Coronavirus/veterinaria , Genotipo , Virus de la Bronquitis Infecciosa/clasificación , Virus de la Bronquitis Infecciosa/genética , Enfermedades de las Aves de Corral/virología , Animales , Pollos , Análisis por Conglomerados , Infecciones por Coronavirus/virología , Egipto , Variación Genética , Virus de la Bronquitis Infecciosa/aislamiento & purificación , Filogenia , Reacción en Cadena de la Polimerasa , Recombinación Genética , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Serogrupo , Proteínas Estructurales Virales/genética
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