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.

[Q]: 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?
[A]: 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.


[Q]: Context: Glial cell line-derived neurotrophic factor (GDNF) and N-cadherin interact to transduce intracellular signals. However, the specific molecular mechanisms of this interaction are unclear. This study attempted to detect changes in GDNF-induced β-catenin phosphorylation and nuclear translocation in C6 glioma cells.', 'C6 glioma cells were treated with GDNF (70 ng/mL) and membrane and cytoplasmic proteins were extracted. A N-cadherin antibody was used for co-immunoprecipitation (co-IP). Western blot analysis using the co-IP protein was completed using antibodies for β-catenin, Src and β-actin. Immunocytochemistry was conducted with the same antibodies. To determine if Src induced phosphorylation of β-catenin Tyr-654, Western blot analysis was also performed on nuclear proteins from C6 cells treated with tyrosine kinase inhibitor PP2 using then p- β-catenin antibody.', 'After induced by GDNF, C6 cell membrane β-catenin was phosphorylated at Tyr-654 and subsequently separated from the N-cadherin/β-catenin complex. Further study confirmed that the induction by GDNF significantly increased cytoplasmic and nuclear expression of phospho-β-catenin (Tyr-654) in C6 glioma cells. There was also an increase in the binding of non-receptor protein kinase Src with N-cadherin on the inner cell membrane surface. Src induced phosphorylation of β-catenin Tyr-654 induced by GDNF decreased significantly.\Question: Does glial cell line-derived neurotrophic factor promote β-catenin phosphorylation and nuclear translocation in glioma cells?
[A]: The results of our study demonstrate that GDNF increases the intracellular phosphorylation level of β-catenin through N-cadherin/Src signaling, which subsequently stimulates the nuclear translocation of β-catenin. This study provides a theoretical basis for us to reveal the role of biological mechanisms on glioma cell by GDNF.


[Q]: Context: To test whether an acute transfusion practice of packed red blood cells (pRBC) : fresh-frozen plasma (FFP) 1 : 1 would be associated with reduced mortality in acute bleeding multiply injury.', 'Retrospective analysis using the TR-DGU database (Trauma Registry of the Deutsche Gesellschaft für Unfallchirurgie 2002-2006) on primary admissions with substantial injury (Injury Severity Score > 16) and massive transfusion (> 10 pRBCs). Seven hundred thirteen patients were divided into three groups according to the pRBC : FFP ratio transfused, that is, (i) pRBC : FFP > 1.1; (ii) pRBC : FFP 0.9-1.1 (1 : 1); and (iii) pRBC : FFP < 0.9, and mortality rates were compared.', 'Four hundred ninety-seven (69.7%) of patients were male, the mean age was 40.1 (+/- 18.3) years. Injury characteristics and pathophysiological state upon emergency room arrival were comparable between groups. Out of 713, 484 patients had undergone massive transfusion with pRBC : FFP > 1.1, 114 with pRBC : FFP 0.9-1.1 (1 : 1), and 115 with pRBC : FFP < 0.9 ratios. Acute mortality (< 6 h) rates for pRBC : FFP > 1.1, pRBC : FFP 0.9-1.1 (1 : 1), and pRBC : FFP < 0.9 ratios were 24.6, 9.6 and 3.5% (P < 0.0001), 24-h mortality rates were 32.6, 16.7 and 11.3% (P < 0.0001), and 30-day mortality rates were 45.5, 35.1 and 24.3% (P < 0.001). The frequency for septic complications and organ failure was higher in the pRBC : FFP 0.9-1.1 (1 : 1) group, ventilator days and length of stays for intensive care unit and overall in-hospital were highest in the pRBC : FFP < 0.9 ratio group (P < 0.0005).\Question: Are red-blood-cell to plasma ratios transfused during massive transfusion associated with mortality in severe multiple injury : a retrospective analysis from the Trauma Registry of the Deutsche Gesellschaft für Unfallchirurgie?
[A]:
An association between pRBC : FFP transfusion ratios and mortality to favour early aggressive FFP administration was observed. Further investigation is necessary prior to recommending routine 1 : 1 or more aggressive FFP use in exsanguinating patients.