The complete nucleotide sequence has been determined of a strain poliovirus type 3, P3/119, isolated from the central nervous system victim fatal vaccine-associated poliomyelitis. Comparison this with those obtained previously for Sabin 3 vaccine, P3/Leon 12a 1 b and its neurovirulent progenitor, P3/Leon/37, reveals that these three strains are on direct geneaological lineage therefore P3/119 is bona fide revertant vaccine. differs in attenuated vaccine parent at just seven positions. Only...

Infectious recombinant viruses were constructed from three molecularly cloned human immunodeficiency virus (HIV) strains varying in cell tropism. All recombinants showed a high infectivity titer on phytohemagglutinin-stimulated normal T lymphocytes. However, 120-bp region of the envelope gene including area V3 hypervariable loop was found to influence both clone 1022 CD4-positive HeLa cells and CEM leukemia cells. Infectivity for macrophages more complex. replicated low level, but viral...

The human immunodeficiency virus type 1 (HIV-1) and T-cell leukemia I (HTLV-I) are two distinct retroviruses that infect T cells. Recent epidemiologic studies have identified a cohort of individuals coinfected with both viruses. It is reported here peripheral blood leukocytes infected HIV-1 in vitro can be induced to produce large quantities after mitogenic stimulation by noninfectious HTLV-I virions. also shown virions may exert this effect prior to, immediately following, or well the cells...

Specific point mutations which affect viral tropism have been identified in both the V3 loop and CD4-binding region of human immunodeficiency virus type 1 surface glycoprotein gp120. Here we report that a single mutation first variable (V1) strain JRCSF is responsible for change tropism.

The complete nucleotide sequence of the genome Sabin vaccine strain poliovirus type 3 (P3/Leon 12 a 1 b) has been determined from cDNA cloned in E. coli. comprises 51 non-coding region 742 nucleotides, large open reading frame 6618 nucleotides (89% sequence) and 3' 72 nucleotides. There is 77.4% base-sequence homology 89.6% predicted amino-acid between types 3. Conservation all glutamine-glycine tyrosine-glycine cleavage sites suggests mechanism polyprotein processing similar to that...

Different isolates of human immunodeficiency virus type 1 (HIV-1) vary in the cell tropisms they display, i.e., range types which are able to establish a productive infection. Here, we report on phenotypes recombinants between two molecularly cloned strains HIV-1. Our results prove that envelope glycoprotein gp120 is solely responsible for difference tropism parental and no other genes or sequences involved determining these strains. The region determination includes encode V3 loop gp120....

Different strains of human immunodeficiency virus type 1 (HIV-1) vary in the ability to replicate cells that bear HIV-1 receptor, CD4. The mechanism responsible for these cell tropism differences is unknown. We examined different isolates with regard replication specific tumor-derived CD4-positive T-cell lines and normal peripheral blood lymphocytes. To investigate early events life cycle at low multiplicities infection, we used a modification polymerase chain reaction method. Use...

The mechanism of cellular transformation by the human T-cell leukemia viruses (HTLV) is thought to involve a novel gene known as x gene. This essential for HTLV replication and acts enhancing transcription from long terminal repeat. product may also cause aberrant normal genes, resulting in infected cells. Although there no evidence yet such mechanism, it was shown that HTLV-II can activate adenovirus E1A-dependent early promoters therefore has potential genes. It herpes pseudorabies...

The human T-cell leukemia virus (HTLV) types I and II have two nonstructural genes that are encoded in overlapping reading frames. One of these genes, known as tax, has been shown to encode a protein responsible for enhanced transcription (transactivation) from the viral long terminal repeats (LTRs). Genetic evidence indicates second gene HTLV-II, here designated rex, acts trans modulate tax gene-mediated transactivation concentration-dependent fashion. rex may regulate process during life cycle.

Students express widespread dissatisfaction with academic feedback. Teaching staff perceive a frequent lack of student engagement written feedback, much which goes uncollected or unread. Published evidence shows that audio feedback is highly acceptable to students but underused. This paper explores methods produce and deliver range engaged in variety tasks the aim maximising while working towards framework could increase use by teaching staff.

Overlapping cDNA clones representing the entire genone of poliovirus type 3 have been prepared in E. coli by two separate methods. Cloning RNA.cDNA hybrids produced a more comprehensive set with generally larger inserts than cloning double - stranded cDNA. A restriction map genome and nucleotide sequence 2003 bases from 3′ terminus, comprising region encoding protease polymerase proteins, are presented.

AbstractThe Visitors and Residents model of internet use suggests a continuum modes engagement with the online world, ranging from tool to social spaces. In this paper, we examine evidence derived large cohort students assess whether idea can be validated by experimental evidence. We find statistically significant differences between individuals displaying ‘Visitor’ or ‘Resident’ attitudes, suggesting that is useful typology for approaching understanding behaviour. From our limited sample,...

Evidence shows that engaged students perform better academically than disinterested students. Measurement of engagement with education is difficult and imprecise, especially in large student cohorts. Traditional measurements such as summary statistics derived from assessment are crude secondary measures at best do not provide much support for educators to work curate during teaching periods. We have used academic-related contributions a public social network proxy engagement. Statistical...

Laboratory practicals classes are an essential component of all science degrees, but a pinch point because rising student numbers, expectations and falling exposure to laboratory work prior entering higher education. Augmentation physical with online interventions is not new, as virtual laboratories become increasingly sophisticated, cutting-edge approaches have less available many institutions they unable meet the investment or specialist skills needed build maintain these complex tools....

Feedback on academic performance is of critical importance to students' learning, and in their perception the quality instruction they receive. Here we report outcomes a study comparing views expectations first year biological science undergraduate students staff regarding feedback provision utilisation. The results indicate that while are generally satisfied with process, there some tensions generated by perceived differences desired outcomes. In particular, these focus perceptions...