RESUMEN
A RT-PCR method has been developed to diagnose infectious hemopoietic necrosis virus (IHNV) in salmons. The authors show it possible to use the method for viral shedding in both a cell culture and a clinical sample from infected fishes. Genotyping of IHNV strains originating from North America, Europe, and Russia, by using the restriction fragment length polymerase analysis, has revealed that 10 of them belong to 3 existing genogroups (U, M, and L). Three Russian isolates are assigned into a separate subgroup. Phylogenetic analysis of several isolates has confirmed that viral strains from Katchatka belong to the North American U-genogroup whereas 3 Russian isolates from the continental zone of the country make up a separate subgroup within the same genogroup.
Asunto(s)
Enfermedades de los Peces/diagnóstico , Virus de la Necrosis Hematopoyética Infecciosa/clasificación , Virus de la Necrosis Hematopoyética Infecciosa/aislamiento & purificación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Infecciones por Rhabdoviridae/veterinaria , Salmón/virología , Animales , Cartilla de ADN , Enfermedades de los Peces/virología , Genes Virales , Virus de la Necrosis Hematopoyética Infecciosa/genética , Infecciones por Rhabdoviridae/diagnóstico , Sensibilidad y EspecificidadRESUMEN
Mycobacterium tuberculosis strains isolated from patients treated at TB dispensary branches in different districts of Novosibirsk were studied by genetic analysis. The below molecular methods were used: 1. PCR with random primers; 2. A method based on variable number of tandem repeats in loci; 3. IS6110 inverse PCR. Thirty-five samples of genome DNA of M. tuberculosis isolated were analyzed. Each of the 3 methods detected the main group of isolates, which comprised 61.8% of closely related strains revealed by method 1, 75.8%--by method 2, and 74.3%--by method 3. The remaining clusters were represented by 1 to 4 strains. The data obtained denote a relative homogeneity of M. tuberculosis strains circulating in Novosibirsk Region. No interplay was detected between the clustering of isolates and the presence or absence of mutation in genes conditioning the resistance to antibiotics.