Illness and Diseases

Antiviral drugs and antiviral activity assays

Assays of antiviral activity and cytotoxicity were evaluated by the modified sulforhodamine B (SRB) assay previously described and recently reported by Choi et al. Ribavirin was purchased from DUCHEFA (Netherlands); azidothymidine, acyclovir, amantadine, and lamivudine were purchased from Sigma-Aldrich (St. Louis, MO, USA), as was SRB. One day before infection, Vero cells were seeded onto […]

May 17, 2011 – 3:15 pm | By Dan Frost | Posted in Infections | Comments (0)

Genetic diversity of a Korean echovirus 5 isolate. Part 2

At present, some 40 antiviral drugs have been formally licensed for use in humans, mostly for treatment of human immunodeficiency virus, hepatitis B virus, and herpesvirus infections. The number of antiviral drugs that have been licensed for use in treating highly-pathogenic RNA virus infections is very limited; the current list of approved drugs includes anti-influenza […]

May 13, 2011 – 9:18 pm | By Dan Frost | Posted in Infections | Comments (0)

Genetic diversity of a Korean echovirus 5 isolate

Abstract An outbreak of echovirus 5 (ECV 5) occurred in Korea in 2006, marking the first time this virus had been identified in the country since enterovirus surveillance began in 1993. Using a sample isolated from a young male patient with aseptic meningitis, we performed sequencing of the Korean ECV 5 strain and compared it […]

May 6, 2011 – 11:10 pm | By Dan Frost | Posted in Infections | Comments (0)

RNA secondary structure prediction

5′-UTR sequence of DHV-1 ZJ strain (GenBank No. EF382778) was aligned with other DHV-1 isolates from GenBank using DNAstar (DNASTAR Inc.) software. Secondary structure elements were predicted in Mfold. Plasmid construction DNA preparations were performed using standard methods as described in manufacturers’ instructions. The reporter plasmids pGEM-CAT/EMC/LUC, containing the EMCV IRES cDNA, and pGEM-CAT/LUC were […]

April 28, 2011 – 7:33 pm | By Dan Frost | Posted in Hepatitis | Comments (0)

DHV-1 IRES initiation does not require functional eIF4A. Part 2

Some picornaviruses, such as the AEV, contain HCV-like IRES elements organized in two major secondary structure domains, II and III, in which all the structural elements crucial for initiation of translation are located. Mutations within the putative loop of domain IIIe and stem1, 2 inhibited the DHV-1 IRES function. Moreover, the restoration of these structures […]

April 26, 2011 – 4:22 pm | By Dan Frost | Posted in Hepatitis | Comments (0)

DHV-1 IRES initiation does not require functional eIF4A

In order to evaluate the contribution of the remaining component of the eIF4F complex, the RNA helicase eIF4A, two different experimental in vitro approaches were used. Firstly, the effect on DHV-1 translation initiation of two different dominant negative mutants of eIF4A was evaluated. The dominant negative mutant PRRVAA contains a mutation in the conserved Ia […]

April 23, 2011 – 6:47 pm | By Dan Frost | Posted in Hepatitis | Comments (0)

DHV-1 IRES activity is modulated by downstream coding sequences

DHV-1 IRES activity is modulated by downstream coding sequences To further characterize the presence of accessory regulatory sequences downstream of the 5′-UTR of the viral genome, 4 additional dicistronic reporter plasmids were constructed, containing DHV-1 5′-UTR and 10, 40 or 60 nucleotides of the coding region adjacent to the viral 5′-UTR (DHV-1 UTR+10nt, UTR+40nt, UTR+60nt, […]

April 21, 2011 – 8:15 pm | By Dan Frost | Posted in Hepatitis | Comments (0)

The duck hepatitis virus 5′-UTR possesses HCV-like IRES activity. Part 3

The in vitro translation of the reporter proteins was evaluated measuring 35S-methionine incorporation. Cap-dependent translation from the first ORF was determined by the level of CAT expression and internal initiation activity of the different sequences included between the two reporter genes was estimated by the accumulation of fLUC. All the mRNAs expressed CAT efficiently as […]

April 19, 2011 – 5:07 pm | By Dan Frost | Posted in Hepatitis | Comments (0)

The duck hepatitis virus 5′-UTR possesses HCV-like IRES activity. Part 2

According to their secondary structure, picornavirus IRES elements can be divided into four groups that display distinct biological properties. The first group (class I) includes the IRES elements from entero- and rhinoviruses (e.g. poliovirus, PV), while the second includes cardio- and aphthoviruses IRES elements (e.g. encephalomyocarditis virus, EMCV). The IRES element from hepatitis A virus […]

April 16, 2011 – 3:33 pm | By Dan Frost | Posted in Hepatitis | Comments (0)

The duck hepatitis virus 5′-UTR possesses HCV-like IRES activity

Duck hepatitis virus (DHV-1) is a worldwide distributed picornavirus that causes acute and fatal disease in young ducklings. Recently, the complete genome of DHV-1 has been determined and comparative sequence analysis has shown that possesses the typical picornavirus organization but exhibits several unique features. For the first time, we provide evidence that the 626-nucleotide-long 5′-UTR […]

April 14, 2011 – 11:34 pm | By Dan Frost | Posted in Hepatitis | Comments (0)