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: The bradycardic agent zatebradine (UL-FS 49) reduces heart rate without negative inotropic or proarrhythmic effects. The aim was to experimentally characterize the influence of zatebradine on arterial baroreflex sensitivity (BRS) and heart rate variability (HRV) which are generally considered as estimates of vagal activity and have prognostic value in patients after myocardial infarction (MI).', 'Conscious rats were studied 3 days after left coronary artery ligation or sham-operation (SH). BRS was determined by linear regression analysis of RR-interval and mean arterial pressure changes evoked by intravenous (i.v.) injections of methoxamine and nitroprusside. HRV at rest was calculated from high-resolution electrocardiogram-recordings.', 'In MI-rats heart rate was similar to SH-rats, mean arterial pressure was lower and both BRS and HRV were markedly reduced. Zatebradine (0.5 mg/kg i.v.) reduced heart rate in MI-rats from 400 +/- 15 to 350 +/- 19 and in SH-rats from 390 +/- 19 to 324 +/- 6 beats/min without changing mean arterial pressure. Both BRS and HRV were restored in MI- and further increased in SH-rats by the drug. Effects of 0.05, 0.5 and 5 mg/kg zatebradine revealed a dose-dependency of heart rate reduction. The lowest dose enhanced reflex bradycardia despite little effect on heart rate and lack of effect on both reflex tachycardia and HRV.\Question: Does the bradycardic agent zatebradine enhance baroreflex sensitivity and heart rate variability in rats early after myocardial infarction?
[EX A]: Both BRS and HRV are reduced in rats early after MI, indicating a depressed reflex and tonic vagal activity. Treatment with zatebradine enhances both BRS and HRV. These data suggest that the drug has both peripheral and central effects, leading to an increase of vagal control of heart rate.

[EX Q]: Context: Due to increased use of imaging techniques, adrenal incidentalomas are frequently detected. The majority are non-hyperfunctioning adrenocortical tumors. We have previously shown that expression of the gene CYP17, coding for the enzyme in the cortisol pathway, correlates with cortisol release from adrenocortical tumors in vitro. The aim of this study was to compare clinical data with mRNA expression of CYP17 and CYP11B1 in adrenocortical tumors from patients with and without Cushing's syndrome and to identify adrenal tumors that may cause subclinical Cushing's syndrome.", 'A retrospective study of 34 patients undergoing adrenalectomy due to an adrenal tumor.', 'Clinical data were collected. In the adrenal gland the mRNA expression of the genes CYP17 and CYP11B1 was studied with in situ hybridisation technique.', "The median ratio of CYP17/CYP11B1 expression in tumors from patients with Cushing's syndrome was significantly higher than the median ratio in the non-hyperfunctioning tumors. Tumors from 2 patients with subclinical Cushing's syndrome had ratios within the upper range for non-hyperfunctioning tumors.\Question: Does increased ratio of mRNA expression of the genes CYP17 and CYP11B1 indicate autonomous cortisol production in adrenocortical tumors?
[EX A]: The ratio between the expression of the genes CYP17 and CYP11B1 in tumors from patients with Cushing's syndrome is significantly higher than in the non-hyperfunctioning tumors. This indicates that 17alpha-hydroxylase is a major determinant of cortisol overproduction. The patients with subclinical Cushing's syndrome in this study are too few to draw any firm conclusions although the results suggest that subclinical Cushing's syndrome may be identified post-operatively with this method.

[EX Q]: Context: Peripheral arterial disease (PAD) is common among patients on chronic dialysis. Despite severe clinical manifestations, the indication for bypass surgery is controversial, because of the high morbidity and mortality rate of these patients. The less invasive percutaneous transluminal angioplasty (PTA) is a possible alternative, but data about PTA in dialysis patients are scarce.', 'We followed 107 dialysis patients (mean age 67+/-10, 75 males) with 132 ischaemic limbs (97% with critical limb ischaemia and ischaemic foot lesions or rest pain) consecutively treated by PTA.', 'PTA was successful in 97% of cases. Median follow-up was 22 months. Cumulative limb salvage rates at 12, 24, 36 and 48 months were 86, 84, 84 and 62%, respectively. Log-rank test showed an association between major amputation and baseline presence of foot lesions (P=0.04). This association was confirmed by a Cox survival multivariate analysis [hazard ratio (HR)=7.03, 95% confidence interval (CI)=1.1-43.0, P=0.035]. Limb salvage without any new intervention on the same leg was achieved in 70% of the cases, and was associated with the absence of diabetes mellitus (P=0.01), lower number of treated lesions (P=0.04) and proximal level (iliac and/or femoro-popliteal) of PTA (P<0.001). Independent predictors were diabetes mellitus (HR=3.47, 95% CI=1.31-9.17, P=0.01) and proximal PTA (HR=0.28, 95% CI=0.08-0.94, P=0.04). Fifty-three (49%) patients died during follow-up. Patients older than 67 years (the median value in our sample) had a 2.4-fold increase in mortality risk (95% CI=1.4-4.1, P<0.001).\Question: Is percutaneous transluminal angioplasty feasible and effective in patients on chronic dialysis with severe peripheral artery disease?
[EX A]:
PTA is feasible and effective in dialysis patients with PAD, and should be preferred to other more invasive interventions.