800x600 hepatitis b virus (hbv) infection is the main cause of chronic hepatitis, cirrhosis and hepatocellular carcinoma (hcc). several factors such as serum hbv dna level, genotype and specific viral mutations have been clarified to determine disease progression of chronic hepatitis b. among these, mutations can also occur in chronic hbv patients with antiviral treatment such as lamivudine the...

background objectives: the risk of adefovir dipivoxil resistance emergence has increased in lamivudine-resistant hepatitis b infected patients. the mutations known as causing adefovir resistance, rtn236t and rta181v/t, are detected within the d and b functional domain of the hbv polymerase, respectively. in this study, we intended to determine the pre-existing adefovir-resistance mutations in p...

One of the most efficient mechanisms by which plants protect themselves from invading virusesis the specific RNA-dependent silencing pathway termed post-transcriptional gene silencing(PTGS). In this mechanism, resistance to a virus is engineered through the expression of asegment of the virus genomein transgenic plants. Potato VirusY (PVY) is one of the mostdamaging viruses of potato, infecting...

BACKGROUND Emergence of human immunodeficiency virus type 1 (HIV-1) drug resistance may limit the benefits of antiretroviral therapy in resource-limited settings. The prevalence of resistance was assessed among patients from KwaZulu Natal, South Africa, following failure of their first highly active antiretroviral therapy (HAART) regimen. METHODS Genotypic resistance testing was performed on ...

hepatitis c virus (hcv) envelope glycoprotein-2 (e2) inhibits the interferon (ifn)–induced, double –stranded rna activated protein kinase (pkr) via pkr eukaryotic initiation factor-2α phosphorylation homology domain (pephd). present study examined the genetic variability of the pephd in patients receiving interferon therapy. the pephd region from hcv genotype 1a/1b infected patients receiving i...

Interpreting the results of plasma human immunodeficiency virus type 1 (HIV-1) genotypic drug-resistance tests is one of the most difficult tasks facing clinicians caring for HIV-1-infected patients. There are many drug-resistance mutations, and they arise in complex patterns that cause varying levels of drug resistance. In addition, HIV-1 exists in vivo as a virus population containing many ge...

one of the most efficient mechanisms by which plants protect themselves from invading virusesis the specific rna-dependent silencing pathway termed post-transcriptional gene silencing(ptgs). in this mechanism, resistance to a virus is engineered through the expression of asegment of the virus genomein transgenic plants. potato virusy (pvy) is one of the mostdamaging viruses of potato, infecting...

ABSTRACT A new variety of Nicotiana, N. edwardsonii var. Columbia, was evaluated for its capacity to serve as a new source for virus resistance genes. Columbia was developed from a hybridization between N. glutinosa and N. clevelandii, the same parents used for the formation of the original N. edwardsonii. However, in contrast to the original N. edwardsonii, crosses between Columbia and either ...

OBJECTIVES To determine whether pan-protease inhibitor (PI)-resistant virus populations are composed predominantly of viruses with resistance to all PIs or of diverse virus populations with resistance to different subsets of PIs. METHODS We performed deep sequencing of plasma virus samples from nine patients with high-level genotypic and/or phenotypic resistance to all licensed PIs. The nine ...