background: fasciola species are parasitic trematode with world wide distribution that infects wild and domesticated herbivores, particularly ruminants. the aim of the present study was to investigate the intra species variations of f. gigantica, from goats and buffalos isolates in two common geographic climates of iran. methods: fasciola species were collected from goat, buffalo, sheep, and ca...

the pb2 protein of influenza a viruses has been shown as host range determinant. in this study pb2gene of five h9n2 isolates from tehran province during the period of 1998-2001 were partially amplifiedand sequenced to do phylogenetic study. iranian isolates could be classified in eurasian lineage according totheir pb2 gene sequences. the pb2 genes of these isolates are different from those of m...

phylogenetic analysis has shown that escherichia coli is composed of four main phylogenetic groups (a, b1, b2 and d). characterization of phylogenetic groups is of clinical interest, as group a and b1 generally associated with commensals, whereas most enteropathogenic isolates are assigned to group d, and group b2 is associated with extra-intestinal pathotype. one hundred e. coli strains recove...

the earliest evidences on circulation of avian influenza (ai) virus on the iranian poultry farms date back to 1998. great economic losses through dramatic drop in egg production and high mortality rates are characteristically attributed to h9n2 ai virus. in the present work non-structural (ns) genes of 10 iranian h9n2 chicken ai viruses collected during 1998-2007 were fully sequenced and subjec...

background: the emergence and propagation of different phylogenetic groups of antimicrobial-resistant e. coli have become a worldwide health concern in human and veterinary medicine. therefore, the evaluation of the phylogenetic distribution of antibiotic-resistant e. coli is important for therapeutic and economic purposes. the aims of this study were to determine phylogenetic groups and patter...

Introduction: Urinary tract infection (UTI) is one of the most common infectious diseases, and Escherichia coli is known as the most dominant causative agent of this infection in 90-80% of patients. There is not much information about the phylogenetic groups, types, and virulence factors of E. coli, causing UTIs from Iran. The objective of this study was to evaluate the antimicrobial susceptibi...

A fundamental problem in the study of phylogenetic networks is to determine whether or not a given phylogenetic network contains a given phylogenetic tree. We develop a quadratic-time algorithm for this problem for binary nearly-stable phylogenetic networks. We also show that the number of reticulations in a reticulation visible or nearly stable phylogenetic network is bounded from above by a f...

escherichia coli (e. coli) is a normal inhabitant of the gastrointestinal tract of vertebrates, including humans. phylogenetic analysis has shown that e. coli is composed of four main phylogenetic groups (a, b1, b2 and d). group a and b1 are generally associated with commensals, whereas group b2 is associated with extra-intestinal pathotypes. most enteropathogenic isolates, however, are assigne...