Human immunodeficiency virus type 1 (HIV-1) strains dually resistant to zidovudine and lamivudine (3TC) may arise during zidovudine-3TC combination therapy. The objective of this cross-sectional study (n = 43 patients) was to test the association between therapy response (clinical and immunologic) to zidovudine-3TC and the level of phenotypic zidovudine resistance and zidovudine resistance-asso...

Plant steroid hormones, brassinosteroids (BRs), play essential roles in plant growth, development and stress responses. However, mechanisms by which BRs interfere with plant resistance to virus remain largely unclear. In this study, we used pharmacological and genetic approaches in combination with infection experiments to investigate the role of BRs in plant defense against Tobacco Mosaic Viru...

Zidovudine treatment preferentially benefits persons with only non-syncytium-inducing (NSI) human immunodeficiency virus type 1 (HIV-1) variants. To understand this differential efficacy, changes in cellular virus load, clonal composition of HIV-1 populations, and development of resistance-conferring reverse transcriptase mutations were studied in 17 persons initiating zidovudine therapy. Zidov...

Human immunodeficiency virus (HIV) production continues in patients receiving highly active antiretroviral therapy (HAART) with undetectable (<50 copies/mL) virus loads. Our initial cross-sectional study showed that this viremia is composed of viruses that lack new resistance mutations to the HAART regimen. Here we describe a longitudinal, clonal genotypic analysis of plasma virus loads in trea...

Transgenic plants expressing double-stranded RNA (dsRNA) of virus origin have been previously shown to confer resistance to virus infections through the highly conserved RNA-targeting process termed RNA silencing or RNA interference (RNAi). In this study we applied this strategy to soybean plants and achieved robust resistance to multiple viruses with a single dsRNA-expressing transgene. Unlike...

Background and Aims: Influenza A viruses are important pathogens for humans especially in pandemic episodes. Two adamantane derivates, amantadine and rimantadine, are used for prophylaxis and treatment of influenza A virus infections. However, single amino acid substitutions in the M2 transmembrane domain which lead to amantadine resistance of these viruses occur at residues 26, 27, 30, 31 or 3...

Lennefors, B-L. 2006. Molecular breeding for resistance to rhizomania in sugar beets. Doctor’s dissertation ISSN: 1652-6880, ISBN: 91-576-7255-5 Rhizomania is one of the most destructive sugar beet diseases. It is caused by Beet necrotic yellow vein virus (BNYVV) vectored by the soilborne protoctist Polymyxa betae Keskin. The studies in this thesis evaluated natural and transgenic resistances t...

Myxoma virus was introduced into the European rabbit population of Australia in 1950. Although the virus was initially highly lethal in rabbits, there was rapid selection for less virulent strains of virus and innately resistant rabbits. To investigate the basis of resistance to myxoma virus, we have compared the pathogensis of the virulent strain of myxoma virus originally released into Austra...

The evolution of resistance-breaking capacity in pathogen populations has been shown to depend on the plant genetic background surrounding the resistance genes. We evaluated a core collection of pepper (Capsicum annuum) landraces, representing the worldwide genetic diversity, for its ability to modulate the breakdown frequency by Potato virus Y of major resistance alleles at the pvr2 locus enco...

Novel influenza A (H1N1) virus infection continues to cause illness and death among persons worldwide. Immunosuppressed patients with influenza virus infection can shed virus for prolonged periods, increasing the chances for development of drug resistance. On August 6, 2009, CDC detected evidence of resistance to the antiviral medication oseltamivir in two severely immunosuppressed patients wit...