Abstract not available Bangladesh Journal of Medical Science Vol.20(5) 2021 p.185-187

The cross-species transmission of lentiviruses from African primates to humans has selected viral adaptations which have subsequently facilitated human-to-human transmission. HIV adapts not only by positive selection through mutation but also by recombination of segments of its genome in individuals who become multiply infected. Naturally infected nonhuman primates are relatively resistant to A...

Methods Viral reverse transcriptase and protease genes from 369 individuals with newly diagnosed HIV-1 infection were sequenced at baseline. A maximum-likelihood phylogenetic analysis method was employed to examine for linkage between viral isolates. Clinical data were retrieved from the database and cross-referenced with the patients’ medical files. Transmitted drug resistance was defined in a...

The genomes of mammalian species contain multiple copies of sequences homologous to exogenous retroviruses. When a mutant retrovirus carrying a lethal deletion in an essential viral gene was introduced into mammalian cells, revertant viruses appeared and spread throughout the culture. Analysis of one such revertant showed that the mutation had been repaired by homologous recombination with endo...

Background HIV-1 virus is a rapidly evolving virus due to genetic variability through its rapid replication, mutation and recombination potential which is a major hurdle in vaccine development. One of the effective ways to modulate HIV-1 infection is to target viral proteins; among the viral proteins, Tat plays a major role in HIV-1 pathogenesis. It activates viral gene expression through TAR i...

This study described some essential viral and sera-characteristics of A/H7N9 virus infection in a 61-year old case patient. With the antiviral therapy and respiratory support, the patient showed a significant decrease of viral loads from 6.72 log10 copies/mL to 0 in 22 days, and a correlated increase of serum hemagglutination inhibition titers during the same period. Phylogenetic analysis demon...

We have constructed an 8-base-pair insertion mutation in the 3' noncoding region of an infectious poliovirus cDNA clone that gives rise to a temperature-sensitive RNA synthesis mutant upon transfection into mammalian cells. The mutated cDNA was used to establish a cell line that releases the mutant poliovirus in a temperature-dependent fashion, representing a unique persistent viral infection. ...

Transcription and replication of the influenza A virus RNA genome are mediated by the viral RNA polymerase from a promoter consisting of the partially base-paired 3' and 5' termini of viral genome segments. Here we show that transcription and replication can be uncoupled by mutation of an unpaired adenosine in the 5' strand of the promoter. This residue is important for transcription but not re...

Abstract The rapid spread and huge impact of the COVID-19 pandemic caused by emerging SARS-CoV-2 have driven large efforts for sequencing analyzing viral genomes. Mutation analyses revealed that virus keeps mutating shows a certain degree genetic diversity, which could result in alteration its infectivity pathogenicity. Therefore, appropriate delineation variants enables us to understand evolut...