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: Serum uric acid (SUA) has been associated to incident hypertension and increased risk of cardiovascular diseases.', 'Among the 2191 subjects enrolled during the last population survey of the Brisighella Heart Study, we identified 146 new cases of arterial hypertension and 394 treated but uncontrolled hypertensive patients with different levels of SUA. Their hemodynamic characteristics have been compared with those of age- and sex-matched normotensive (N. 324) and controlled hypertensive (N. 470) subjects. Then, by logistic regression analysis, we evaluated which factors were associated with a worse BP control under pharmacological treatment.', 'SUA levels were significantly higher in untreated hypertensive and uncontrolled hypertensive patients when compared to normotensives and controlled hypertensive patients. Pulse wave velocity (PWV) was significantly higher (p<0.001) in undiagnosed and uncontrolled hypertensive patients, while controlled hypertensive patients had PWV values comparable to normotensive controls. A similar trend has been observed for the augmentation index (AI). A worse BP control was associated with SUA levels (OR 1277, 95% CI 1134-1600 per mg/dL), AI (OR 1066, 95%CI 1041-1092 per unit), and PWV (OR 1201, 95% CI 1089-1423, per m/s), but not with age, body mass index, nor estimated glomerular filtration rate.\Question: Is high serum uric acid associated to poorly controlled blood pressure and higher arterial stiffness in hypertensive subjects?
[EX A]: Based on our data, SUA seems to be associated with an inadequate BP control in subjects treated with antihypertensive drugs, and subjects with both uncontrolled BP and relatively high SUA levels have also an increased arterial stiffness that (per se) could be a cause of worse BP control under treatment.

[EX Q]: Context: Somatic cells in vitro have a finite life expectancy before entering a state of senescence, but it is unclear whether this state occurs in vivo in kidney development, growth, and aging. We previously showed that human kidney cortex displays telomere shortening with age. In this study, we compared the structural and functional changes in rat kidney with age to phenomena associated with cellular senescence in vitro.', 'We assessed the changes in Fischer 344 rat kidneys from age 1 to 9 months to define growth and development and from age 9 to 24 months to define aging.', 'Rat kidney telomeres were approximately 35 to 40 kb long and did not shorten significantly. Expression of mRNA for p16INK4a, a characteristic senescence gene in vitro, was undetectable in most young rats but rose 27 fold during growth and a further 72-fold during aging. p16INK4a protein was localized to the nucleus and increased with age. p16INK4a mRNA also increased in other tissues. Lipofuscin and senescence-associated beta-galactosidase increased in epithelium with growth and aging and their occurrence was significantly associated with each other. Lipofuscin was particularly found in atrophic nephrons.\Question: Does cell senescence in rat kidneys in vivo increase with growth and age despite lack of telomere shortening?
[EX A]: We conclude that cell senescence occurs in both growth and aging in rat kidney and may contribute to the age-related pathology. These changes are not due to telomere shortening, but may reflect cumulative environmental stress.

[EX Q]: Context: Cerebral pressure passivity (CPP) in sick newborns can be detected by evaluating coupling between mean arterial pressure (MAP) and cerebral blood flow measured by near infra-red spectroscopy hemoglobin difference (HbD). However, continuous MAP monitoring requires invasive catheterization with its inherent risks. We tested whether heart rate (HR) could serve as a reliable surrogate for MAP in the detection of CPP in sick newborns.', 'Continuous measurements of MAP, HR, and HbD were made and partitioned into 10-min epochs. Spectral coherence (COH) was computed between MAP and HbD (COHMAP-HbD) to detect CPP, between HR and HbD (COHHR-HbD) for comparison, and between MAP and HR (COHMAP-HR) to quantify baroreflex function (BRF). The agreement between COHMAP-HbD and COHHR-HbD was assessed using ROC analysis.', 'We found poor agreement between COHMAP-HbD and COHHR-HbD in left hemisphere (area under the ROC curve (AUC) 0.68) and right hemisphere (AUC 0.71). Baroreflex failure (COHMAP-HR not significant) was present in 79% of epochs. Confining comparison to epochs with intact BRF showed an AUC of 0.85 for both hemispheres.\Question: Does baroreflex dysfunction in sick newborns make heart rate an unreliable surrogate for blood pressure changes?
[EX A]:
In these sick newborns, HR was an unreliable surrogate for MAP required for the detection of CPP. This is likely due to the prevalence of BRF failure in these infants.