Given a passage, 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.

Q: Psoriasis is a common benign skin disease characterized by hyperproliferation and abnormal differentiation of keratinocytes. The transcription factor activator protein 1 (AP-1) is known to play an important role in cell proliferation and differentiation.', 'To investigate AP-1 DNA binding activity in psoriatic skin.', 'Keratome biopsies were taken from patients with plaque-type psoriasis. Electrophoretic mobility shift assays were used to determine the AP-1 DNA binding activity, whereas Western and Northern blotting was used to determine Jun and Fos protein and mRNA expression.', 'We found that AP-1 DNA binding activity was almost completely abolished in lesional psoriatic skin compared with nonlesional psoriatic skin. Furthermore, experiments revealed that the protein and mRNA expression of the AP-1 subunits c-Fos, Fra-1 and c-Jun was reduced in lesional psoriatic skin compared with nonlesional psoriatic skin, whereas the protein and mRNA expression of the subunit JunB was increased. Topical application of the vitamin D analogue calcipotriol under occlusion to involved psoriatic skin for 4 days resulted in an increase in AP-1 DNA binding activity, and an increase in the protein and mRNA expression of c-Fos, Fra-1 and c-Jun, together with a decrease in JunB protein and mRNA expression.

A: Is activator protein 1 DNA binding activity decreased in lesional psoriatic skin compared with nonlesional psoriatic skin?
****
Q: Visfatin is an insulin-mimicking adipokine. Visfatin is elevated in obesity and type 2 diabetes. However, its role in glucose and lipid metabolism in healthy humans is unclear.', 'The objective was to investigate the correlations of visfatin with phenotypes of glucose, lipids, and body composition and the responses of visfatin to short-term overfeeding in healthy young men.', 'Sixty-one healthy young men were recruited from the Newfoundland population. Serum visfatin, interleukin 6, glucose, insulin, total cholesterol, HDL cholesterol, LDL cholesterol, and triacylglycerol concentrations were measured with an autoanalyzer, and percentage body fat (%BF) and percentage trunk fat (%TF) were measured with dual-energy X-ray absorptiometry. Insulin resistance and beta cell function were assessed with the homeostasis model. All measurements were completed at baseline and after a 7-d overfeeding protocol exceeding the baseline requirement by 70%. Subjects were classified on the basis of %BF as lean (<21%), overweight (21-25.9%), or obese (>or=26%).', 'Multiple regression analysis showed that triacylglycerols correlated with fasting serum visfatin (P < 0.001). Moreover, serum visfatin decreased 19% overall-23% in lean, 9% in overweight, and 18% in obese subjects (P < 0.0001)-after the overfeeding protocol. None of the variables measured, including interleukin 6, were associated with the reduction in visfatin. In contrast with the findings in mice, visfatin concentrations before and after overfeeding did not correlate with glucose, insulin, insulin resistance, beta cell function, %BF, or %TF.

A: Are serum visfatin concentrations positively correlated with serum triacylglycerols and down-regulated by overfeeding in healthy young men?
****
Q: Although local tissue activation of the endothelin (ET) system contributes to the development of pulmonary hypertension, the impact of isolated chronic plasma hyperendothelinemia on the pulmonary circulation is unknown.', 'Mini-osmotic pumps were implanted in rats to deliver ET-1 during 7 or 28 days. After in vivo hemodynamics, the lungs were isolated to derive pressure-flow relations. Small pulmonary arteries ( approximately 250 microm) were mounted on an isometric myograph to study their reactivity.', 'Plasma ET-1 approximately doubled (p < 0.05) after 7 and 28 days. Lung tissue ET-1 level increased fourfold after 7 days (p < 0.001) but was no longer significantly elevated after 28 days. Right ventricular systolic pressure was unaffected. The pulmonary pressure-flow relation shifted upward with a steeper slope (p < 0.05) at 7 days, but not after 28 days. Maximum dilatations to both acetylcholine (p < 0.01) and sodium nitroprusside (p < 0.001) were greatly reduced by approximately 50% after 28 days and were normalized by the addition of the nitric oxide synthase inhibitor L-NNA and the antioxidant N-acetyl-L-cysteine, respectively.

A:
Do chronically elevated endothelin levels reduce pulmonary vascular reactivity to nitric oxide?
****