Neonatal sepsis is a disease affecting newborns ≤1 month of age with clinical symptoms and positive blood cultures. The number of Escherichia coli strains causing neonatal sepsis resistant to the antibiotics used in the treatment is increasing. In this study, two E. coli strains causing sepsis in neonates of mothers infected with an E. coli strain harboring extended spectrum beta-lactamases wer...

Analysis of unidirectional genomic deletion events and single nucleotide variations suggested that the four subspecies of Francisella tularensis have evolved by vertical descent. The analysis indicated an evolutionary scenario where the highly virulent F. tularensis subsp. tularensis (type A) appeared before the less virulent F. tularensis subsp. holarctica (type B). Compared to their virulent ...

Newcastle disease (ND) is a highly contagious disease that affects many species of birds and causes significant economic losses to the poultry industry worldwide and the pathogenicity of Newcastle disease virus (NDV) strains varies with different virulence. Samples were collected from chicken commercial farms in Iran during 2014–2015. ND virus were characterized (NDV) by partial sequences...

staphylococcus aureus carrying pvl gene remain major health problem associated with highly virulent infections. characterization of such gene is important to know the impact and the functional significance of nucleotide variations. pcr and standard sequencing were performed for twelve sudanese strains from different sources. protein structures prediction, modeling and physiochemical analysis we...

A plaque technique was found useful for the differentiation and titration of two vaccine strains and a local highly virulent field isolate of Newcastle disease virus.

Virulent strains of Salmonella opsonized with normal mouse plasma are never phagocytosed as well as avirulent strains. The virulent strains of Salmonella phagocytosed after opsonization with normal mouse plasma are able to multiply within normal mouse peritoneal macrophages, whereas under similar experimental conditions the avirulent strains are killed. When virulent strains of Salmonella are o...

The virulence of Pasteurella multocida (P. multocida) serotype A1 for chickens and mice was determined. Groups of chicken and mice were exposed intramuscularly and intraperitoneally to various concentration of P. multocida broth culture, respectively. This strain was highly virulent for chickens so that those exposed to only 7 c.f.u. of the organism died in less than 24 hours. Groups of mice ex...

Sixty-two strains of Gibberella pulicaris (anamorph: Fusarium sambucinum) from diseased plants and from soil were tested for tolerance of the furanocoumarin xanthotoxin in vitro. Twenty-one (88%) of the plant-derived strains and two (5%) of the soil-derived strains were highly tolerant ofxanthotoxin. Sixteen selected strains were tested further against 16 furanocoumarins or furanocoumarin precu...

Brucella melitensis causes brucellosis, a disease affecting sheep, cattle, and sometimes humans. Attenuated B. melitensis strain M5-90, derived from virulent strain M28, is widely used as a live vaccine in ruminants in China. Genetic differences between the strains may cast light on the mechanism of attenuation. We recently reported the complete genomic sequences of M28 and M5-90. Genome organi...