Q: Given a passage with a context and an answer, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.
Context: Oxidative stress occurs in chronic renal failure patients undergoing hemodialysis (HD). The objective of our study was to measure oxidation products of cholesterols, so-called oxysterols, in the serum of HD patients in comparison to healthy control persons.', 'In 42 HD patients, plasma oxysterols were measured before and after HD. The values were compared with those in 40 healthy controls. The following cholesterol derivatives were analyzed: dienes, 7beta-OH, beta-epoxy, alpha-epoxy, 20alpha-OH, alpha-triol, and 7-keto cholesterol.', 'In HD patients, serum levels of oxysterols are increased in comparison to controls. The highest values were measured for beta-epoxy cholesterol and for 20alpha-OH cholesterol. During HD oxysterol concentrations increased, obviously by water removal and concentration of nondialyzable compounds.
Answer: Due to oxidative stress which is known as a typical sign of chronic renal failure the plasma concentrations of oxysterols are also significantly increased in comparison to healthy controls. This underlines the data on accelerated lipid peroxidation in end-stage renal disease (ESRD) patients. Accumulated oxysterols which are accused of exerting atherosclerosis-stimulating effects, which can contribute to the increased cardiovascular risk of ESRD patients, could either induce atherosclerosis via signaling or chronic effects. Direct chemical reactions stimulating plaque formation can be excluded because of the low levels of oxysterols. The share of oxysterols within the total cholesterol ranges from 4 to 15 per thousand.
A:
Are oxysterols increased in plasma of end-stage renal disease patients?