BACKGROUND Francisella tularensis is a highly virulent human pathogen. The most virulent strains belong to subspecies tularensis and these strains cause a sometimes fatal disease. Despite an intense recent research effort, there is very limited information available that explains the unique features of subspecies tularensis strains that distinguish them from other F. tularensis strains and that...

Recent studies of Toxoplasma gondii isolates from animals in Brazil have revealed high genetic diversity. Many of these isolates are virulent to mice. It is speculated that these isolates may also be virulent to humans. However, there is very limited data regarding T. gondii strains from human infection. Therefore, it is not clear whether there is any association between parasite genotypes and ...

Cytokinin activity in the culture medium of four pathogenic strains of Corynebacterium fascians varied from 168 to 0.4 mug of kinetin (6-furfurylaminopurine) equivalents per liter, as compared to 0.2 in an avirulent control. N(6)-Isopentenyladenine was the predominant cytokinin in the medium of all five strains, and its increased production was correlated with the degree of pathogenicity; howev...

Insecticide susceptibility and virulence to resistant rice varieties were determined and evaluated in the brown planthopper (BPH) and the whitebacked planthopper (WBPH), collected from Asian countries (Japan, China, Taiwan, northern Vietnam, southern Vietnam, and Philippines) in 2006. Insecticide susceptibility was determined by a topical application method using four insecticides. Virulence to...

BACKGROUND The use of prototypic strains is common among laboratories studying infectious agents as it promotes consistency for data comparability among and between laboratories. Schu S4 is the prototypic virulent strain of Francisella tularensis and has been used extensively as such over the past six decades. Studies have demonstrated virulence differences among the two clinically relevant sub...

The Pasteurella multocida capsular type A isolates can cause pneumonia and bovine respiratory disease (BRD). In this study, comparative genomics analysis was carried out to identify the virulence genes in two different virulent P. multocida capsular type A isolates (high virulent PmCQ2 and low virulent PmCQ6). The draft genome sequence of PmCQ2 is 2.32 Mbp and contains 2,002 protein-coding gene...

BACKGROUND MicroRNAs are short RNAs (~22 nt) expressed by plants, animals and viruses that regulate gene expression post-transcriptionally, and their importance is highlighted by distinct patterns of expression in many physiological processes, including development, hematopoeisis, stress resistance, and disease. Our group has characterized the microRNAs encoded by the avian herpesviruses; namel...