Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.
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Question: Context: Pandemic strains of HIV-1 (group M) encode a total of nine structural (gag, pol, env), regulatory (rev, tat) and accessory (vif, vpr, vpu, nef) genes. However, some subtype A and C viruses exhibit an unusual gene arrangement in which the first exon of rev (rev1) and the vpu gene are placed in the same open reading frame. Although this rev1-vpu gene fusion is present in a considerable fraction of HIV-1 strains, its functional significance is unknown.', 'Examining infectious molecular clones (IMCs) of HIV-1 that encode the rev1-vpu polymorphism, we show that a fusion protein is expressed in infected cells. Due to the splicing pattern of viral mRNA, however, these same IMCs also express a regular Vpu protein, which is produced at much higher levels. To investigate the function of the fusion gene, we characterized isogenic IMC pairs differing only in their ability to express a Rev1-Vpu protein. Analysis in transfected HEK293T and infected CD4+ T cells showed that all of these viruses were equally active in known Vpu functions, such as down-modulation of CD4 or counteraction of tetherin. Furthermore, the polymorphism did not affect Vpu-mediated inhibition of NF-B activation or Rev-dependent nuclear export of incompletely spliced viral mRNAs. There was also no evidence for enhanced replication of Rev1-Vpu expressing viruses in primary PBMCs or ex vivo infected human lymphoid tissues. Finally, the frequency of HIV-1 quasispecies members that encoded a rev1-vpu fusion gene did not change in HIV-1 infected individuals over time.
Answer: Expression of a rev1-vpu fusion gene does not affect regular Rev and Vpu functions or alter HIV-1 replication in primary target cells. Since there is no evidence for increased replication fitness of rev1-vpu encoding viruses, this polymorphism likely emerged in the context of other mutations within and/or outside the rev1-vpu intergenic region, and may have a neutral phenotype.

Answer: Does a Naturally Occurring rev1-vpu Fusion Gene Confer a Fitness Advantage to HIV-1?

Question: Context: To establish the role of FHIT in the pathogenesis hepatocellular carcinoma (HCC).', 'We examined genomic alterations, as well as, mRNA and protein expression patterns from the FHIT gene, in 48 surgically resected hepatocellular carcinoma (HCC) tissues. Additionally, p53 mutations were analyzed.', 'Aberrant FHIT transcripts were detected in 11 of 48 surrounding non-tumor liver tissues and 27 of 48 HCC samples (22.9% vs 56.3%, P = 0.002). No point mutations were identified within the open reading frame region of FHIT. Loss of heterozygosity (LOH) of the FHIT locus was detected in 4 of 42 informative cases for D3S1300, and 3 of 29 informative cases for D3S1313. Reduced expression of FHIT protein (Fhit) was observed in 8 (16.7%) of 48 HCC samples, with complete loss of Fhit in only 1 case. There were no associations with abnormal transcripts, LOH, and Fhit expression. p53 mutations were identified in 9 of the 48 HCC cases. However, none of the cases displayed a G to T transversion at p53 codon 249.
Answer: Aberrant FHIT transcripts were more common in HCC tissues as compared to non-cancerous liver tissues. However, Fhit expression was lost or reduced in a minor fraction of HCC tissues, while it was strongly expressed in non-cancerous liver tissues. Therefore, our study suggests that FHIT plays a role in relatively few HCC cases in South Korea.

Answer: Are fragile histidine triad gene alterations essential for hepatocellular carcinoma development in South Korea?

Question: Context: Children's fruit/vegetable intake is still below recommended levels. This study applied Internet-tailored advice for schoolchildren and Internet-supported brief dietary counselling (with child and parent) within preventive health care to promote fruit/vegetable intake.", 'The study involved 30 seventh-grade classes (16 in the intervention group and 14 in the control group) with a total of 675 children aged 9-12 years, of whom 495 were allowed to participate.', 'A cluster-randomised baseline-post-test experimental design was applied. During school hours, all children completed Internet-administered questionnaires on fruit/vegetable intake and related determinants. Children in the intervention group received immediate online individually tailored nutrition feedback. For each child in the intervention group, a nurse received information concerning the assessment of fruit/vegetable intake via the Internet to support a 5 min counselling protocol to promote fruit/vegetable intake. Children completed a similar post-test questionnaire 3 months after the first assessment. Intention-to-treat analyses were conducted using multilevel regression analyses.', 'A total of 486 children (98% of 495) participated (263 in the intervention group, 223 in the control group); 240 child-parent couples in the intervention group attended the counselling. Awareness of inadequate fruit intake (odds ratio (OR) = 3.0; 95% confidence interval (CI) = 1.8-5.3) and knowledge of recommended vegetable intake levels (OR = 2.7; 95% CI = 1.8-4.1) were significantly more likely at post-test in the intervention group than in the control group. No significant effects were found on intake or other determinants.
Answer: A compact, integrated two-component intervention can induce positive changes in knowledge and awareness of intake levels of fruit/vegetables among schoolchildren. To induce changes in intake levels, more comprehensive interventions may be needed.

Answer:
Does school-based internet-tailored fruit and vegetable education combined with brief counselling increase children 's awareness of intake levels?