instruction:
In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
question:
Context: HBV covalently closed circular DNA (cccDNA), the replicative intermediate responsible for persistent HBV infection of hepatocytes, is the template for transcription of all viral mRNAs. Nuclear cccDNA accumulates as a stable episome organized into minichromosomes by histone and nonhistone proteins. In this study we investigated, by a newly developed sensitive and specific assay, the relationship between viral replication and HBV chromatin assembly, transcription, and interaction with viral and cellular regulatory proteins.', 'To achieve this aim we coupled a quantitative chromatin immunoprecipitation (ChIP) technique to an established method that allows the amplification of virion-encapsidated HBV genomes after transfection of linear HBV DNA into human hepatoma HuH7 cells. The cccDNA-ChIP technique was also applied to study HBV minichromosome transcriptional regulation in liver tissue from HBV-infected patients.', 'The use of anti-acetyl-H4/-H3 specific antibodies to immunoprecipitate transcriptionally active chromatin revealed that HBV replication is regulated by the acetylation status of the cccDNA-bound H3/H4 histones. Class I histone deacetylases inhibitors induced an evident increase of both cccDNA-bound acetylated H4 and HBV replication. Finally, histones hypoacetylation and histone deacetylase 1 recruitment onto the cccDNA in liver tissue correlated with low HBV viremia in hepatitis B patients.\Question: Is hepatitis B virus replication regulated by the acetylation status of hepatitis B virus cccDNA-bound H3 and H4 histones?
answer:
We developed a ChIP-based assay to analyze, in vitro and ex vivo, the transcriptional regulation of HBV cccDNA minichromosome. Our results provide new insights on the regulation of HBV replication and identify the enzymatic activities that modulate the acetylation of cccDNA-bound histones as new therapeutic targets for anti-HBV drugs.


question:
Context: To investigate the expression of scavenger receptor that binds phosphatidylserine and oxidized lipoprotein (SR-PSOX)/CXC chemokine ligand 16 (CXCL16) in the human monocyte-derived cell line THP-1, and the effect of lentiviral vectors for the stable delivery of SR-PSOX/CXCL16 short hairpin RNA on foam cell formation.', 'A lentiviral expression vector containing enhanced green fluorescence protein (GFP) and SR-PSOX small interfering RNA (siRNA) (Lenti-SR-PSOXsi), or the control siRNA (Lenti-NC) gene was constructed. A human monocyte-derived cell line THP-1 was transfected with a different multiplicity of infection (MOI) of Lenti-SR-PSOXsi or Lenti-NC, and cultured to obtain stably-transfected THP- 1KD and THP-1NC cells. After incubation with oxidatively-modified, low-density lipoprotein (Ox-LDL), the expression of SR-PSOX/CXCL16 mRNA was determined by real-time PCR. The expression of the SR-PSOX/CXCL16 protein was detected by flow cytometry analysis. The effect of Lenti-SR-PSOXsi on foam cell formation was assessed by Oil red O-stain analysis.', 'Ox-LDL increased the expression of SR-PSOX/CXCL16 mRNA in a time- and dose-dependent manner in THP-1 cells. Four days after transfection with Lenti-SR-PSOXsi (MOI: 100), the percentage of GFP expression cells was over 89.3%. The expression of the SR-PSOX/ CXCL16 mRNA and protein in THP-1KD cells significantly decreased compared with the parent cells, even the THP-1KD cells stimulated with 40 mg/L Ox-LDL. Ox-LDL uptake experiments in THP-1- and THP-1KD-derived macrophages indicated that SR-PSOX/CXCL16 deficiency decreased the development of macrophage- derived foam cell formation.\Question: Does lentiviral vector-mediated siRNA knockdown of SR-PSOX inhibit foam cell formation in vitro?
answer:
The above data showed that SRPSOX siRNA delivered by using lentiviral vectors in THP-1 cells was a powerful tool for studying the effect of SR-PSOX, and decreased the expression of the SRPSOX gene by inhibiting macrophage-derived foam cell formation.


question:
Context: Alcohol increases the tendency for risky driving in some individuals but not others. Little is known about the factors underlying this individual difference. Studies find that those who underestimate their blood alcohol concentration (BAC) following a dose of alcohol tend to be more impulsive and report greater willingness to drive after drinking than those who estimate their BACs to be greater than their actual BAC. BAC underestimation could contribute to risky driving behavior following alcohol as such drivers might perceive little impairment in their driving ability and thus no need for caution.', "This study was designed to test the relationship between drivers' BAC estimations following a dose of alcohol or a placebo and the degree of risky driving they displayed during a simulated driving test.", 'Forty adult drivers performed a simulated driving test and estimated their blood alcohol concentration after receiving a dose of alcohol (0.65 g/kg for men and 0.56 g/kg for women) or a placebo.', 'Alcohol increased risk-taking and impaired driving skill. Those who estimated their BAC to be lower were the riskiest drivers following both alcohol and placebo.\Question: Do drivers who self-estimate lower blood alcohol concentrations are riskier drivers after drinking?
answer:

The tendency to estimate lower BACs could support a series of high-risk decisions, regardless of one's actual BAC. This could include the decision to drive after drinking.