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Abstract: A synthetic cytomegalovirus (CMV) promoter-driven cDNA minigenome containing the enhanced green fluorescence protein (EGFP) gene as a reporter was derived from the genomic segment A of infectious bursal disease virus (IBDV). The 5′-end of the minigenome was fused to the transcription start site of the immediate early CMV promoter, and the hepatitis delta virus (HDV) ribozyme sequence was added at its 3′-end. We show that co-transfection of the minigenome with a plasmid encoding the IBDV RNA-dependent RNA polymerase VP1, results in a consistent increase of the EGFP expression, as measured by fluorescence microscopy and flow cytometry assays. Replication of the minigenome-derived transcript was evidenced by real-time RT-PCR analyses targeted to both the plus- and minus-sense strands. When cells were infected with IBDV and transfected with the plasmid carrying the minigenome, the minigenome was packaged and EGFP was found to be expressed in a second cycle of infection. These results show the potential use of this system as a new tool to characterize IBDV replication and genome packaging. [Copyright &y& Elsevier]

Discusses coronaviruses. Transmissible gastroenteritis virus (TGEV) as a major pathogen causing a fatal diarrhea in newborn pig; Investigation of the molecular determinants of the infection; Evidence supporting the view that the peptidase itself acts as a receptor; Details.

Abstract: The influenza viruses contain a segmented, negative strand RNA genome. Each RNA segment is covered by multiple copies of the nucleoprotein (NP) and is associated with the polymerase complex into ribonucleoprotein (RNP) particles. Despite its importance in the virus life cycle, the interactions between the NP and the genome are not well understood. Here, we studied the assembly process of NP-RNA oligomers and analyzed how the oligomeric/monomeric status of RNA-free NP affects RNA binding and oligomerization. Recombinant wild-type NP purified in low salt concentrations and a derived mutant engineered for oligomerization deficiency (R416A) were mainly monomeric in RNA-free solutions as shown by biochemical and electron microscopy techniques. NP monomer formed with RNA a fast 1/1 complex characterized by surface plasmon resonance. In a subsequent and slow process that depended on the RNA length, oligomerization of NP was mediated by RNA binding. In contrast, preparations of wild-type NP purified in high salt concentrations as well as mutant Y148A engineered for deficiency in nucleic acid binding were partly or totally oligomeric in RNA-free solutions. These trimer/tetramer NP oligomers bind directly as oligomers to RNA with a higher affinity than that of the monomers. Both oligomerization routes we characterized could be exploited by cellular or viral factors to modulate or control viral RNA encapsidation by NP. [Copyright &y& Elsevier]

Objectives The Sensio study objectives were to assess the outcome of neuropsychiatric adverse reactions (NPAR) that develop after initiation of efavirenz (EFV) therapy, to ascertain the late NPAR after a 3-month treatment period, to evaluate the impact of NPAR on patients' quality of life (QoL) in a real-life population. Methods During a 6-month period, consecutive HIV-infected adult outpatients receiving an ongoing EFV therapy for at least 3 months were asked to fill in a specifically designed self-administered questionnaire addressing sleep disturbances, behavioural changes, mood disturbances, anxiety, cognitive disorders, hallucinations, dizziness and the general impact on patients' QoL. Results A total of 174 questionnaires were analyzed. The main late emergent NPAR were sleep disorders: abnormal dreams 24.7%, nocturnal waking 19.6%, trouble falling asleep 17.8%; cognitive disorders: memory disorders 23.0%, impaired concentration 18.9%; anxiety 15.5%; mood disorders: sadness 19.3%, suicidal ideations 9.2%. Global neuropsychic discomfort was moderate to severe in 23% of patients after a 3-month treatment period. Conclusion NPAR occur mainly during the first month of EFV therapy but often persist thereafter. A significant percentage of patients reported suicidal ideations at the time of the study. Our results suggest the need for routine screening for NPAR among patients receiving EFV therapy and better management. [ABSTRACT FROM AUTHOR]

We have applied an automated real‐time quantitative PCR assay using a double‐labeled fluorogenic probe to detect t(9;22)‐positive cells in haematological malignancies. The results are expressed as the ratio of chimeric bcr‐abl transcripts on abl transcripts. Highly reproducible results were obtained for t(9;22)‐positive K562 RNA. Ten copies of bcr‐abl DNA from a recombinant KW‐3 plasmid and one positive cell in 104 can be detected. Thirty‐two patients with chronic myeloid leukaemia (CML), 25 with acute leukaemia, 12 with myelodysplastic syndromes and 7 with other myeloproliferative syndromes were tested. Follow‐up data were obtained in bcr‐abl positive cases. Results were compared with those of conventional nested RT‐PCR and cytogenetics. Real‐time quantitative RT‐PCR values correlated well with both these methods. However, in some cases the only means of detecting early relapse or blastic transformation was to examine the kinetics of real‐time quantitative RT‐PCR. Thus, real‐time quantitative RT‐PCR appears suitable for the diagnosis and follow‐up of patients with the t(9;22) translocation. [ABSTRACT FROM AUTHOR]