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.

[EX Q]: Context: Anti-epileptic drugs (AEDs) and the ketogenic diet (KD) are often used concomitantly in children with refractory epilepsy. It has been hypothesised that certain AEDs may interfere with KD. The purpose of this study was to elucidate relationships between efficacy of KD and use of specific AEDs.', "A retrospective study was performed in 71 children with refractory epilepsy starting the KD between 2008 and 2014 in Erasmus University Hospital Sophia Children's Hospital. Efficacy of the KD (defined as 50% seizure reduction) was evaluated after three months of treatment and related to the AEDs used.", 'The KD was successful after three months in 61% of the children (N=71). Efficacy was significantly reduced if children (n=16) used lamotrigine (31%) at diet initiation or in the course of the diet, compared to other antiepileptic drugs (69%) (p=0.006). In comparison to children using other antiepileptic drugs, the percentage of children that had adequate ketosis was significantly reduced in case of lamotrigine use (p=0.049).\Question: Is concomitant lamotrigine use associated with decreased efficacy of the ketogenic diet in childhood refractory epilepsy?
[EX A]: Lamotrigine treatment during KD is associated with a decreased efficacy of the KD.

[EX 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?
[EX 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.

[EX Q]: Context: To examine whether total and abdominal adiposity are risk factors for the development of chronic heart failure (CHF) in older men and women.', 'Prospective, longitudinal cohort: The Health, Aging and Body Composition study.', 'Memphis, Tennessee, and Pittsburgh, Pennsylvania, metropolitan areas.', 'Three thousand seventy-five well-functioning community-dwelling older adults aged 70 to 79.', 'Body composition using dual energy X-ray absorptiometry, visceral adipose tissue area using computed tomography, adjudicated CHF.', 'Of the remaining (640 participants excluded from original group of 3,075) 2,435 participants (1,081 men, 1,354 women) without coronary heart disease or CHF at baseline, there were 166 confirmed diagnoses of CHF during the median+/-standard deviation (SD) follow-up of 6.1+/-1.4 years. After adjustment for age, race, sex, site, education, smoking, and chronic obstructive pulmonary disorder, all adiposity variables (body mass index (BMI), adipose tissue mass, percentage body fat, waist-to-thigh ratio, waist circumference, and visceral and subcutaneous abdominal adipose tissue) were significant predictors of the development of CHF. In a model that included waist circumference and BMI, waist circumference was associated with incident CHF (hazard ratio (HR)=1.27, 95% confidence interval (CI)=1.04-1.54 per SD increase, P=.02), but BMI was not (HR=1.08, 95% CI=0.86-1.35). When waist circumference and percentage fat were included together, both variables were significant predictors of CHF (waist: HR=1.17, 95% CI=1.00-1.36 per SD increase, P=.05; percentage fat: HR=1.47, 95% CI=1.16-1.87 per SD increase, P=.002). Stepwise adjustment for inflammation, hypertension, insulin resistance, and diabetes mellitus did not decrease the relative risk of a greater waist circumference for the development of CHF (all HR=1.27-1.32, 95% CI=1.02-1.61 per SD increase).\Question: Is abdominal obesity an independent risk factor for chronic heart failure in older people?
[EX A]:
Abdominal body fat distribution may be a stronger risk factor for CHF than overall obesity.