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.

Input: Consider Input: Context: Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is a member of growth factors that have been implicated in skin patho-physiology. Although endothelial nitric oxide synthase (eNOS) and vascular endothelial growth factor (VEGF) appear to be involved in mitogenesis and chemotaxis in epidermal keratinocytes, the activation of eNOS and VEGF production induced by HB-EGF and its signaling mechanism remains undefined.', 'We examined possible signal transduction pathways by which HB-EGF leads to eNOS activation and VEGF production in human epidermal keratinocyte cell line (HaCaT cells).', 'The phosphorylation of epidermal growth factor receptor (EGFR), mitogen-activated protein kinase (MAPK; p42/p44 MAPK), Akt and eNOS were examined by Western blotting analysis. VEGF production was determined by enzyme-linked immunosorbent assay. Various inhibitors were utilized to investigate the signaling mechanisms of eNOS activation and VEGF production.', 'HB-EGF-induced phosphorylation of EGFR with maximum phosphorylation at 1h. HB-EGF-induced phosphorylation of p42/p44 MAPK in a few minutes. It activated Akt with maximum phosphorylation at 1h and eNOS with maximum phosphorylation at 3h. The HB-EGF-induced eNOS activation was significantly blocked by the p42/p44 MAPK inhibitor U0126 and the phosphatidylinositol 3-kinase (P13K) inhibitor LY294002. HB-EGF increased VEGF production. The HB-EGF-induced VEGF production was blocked by U0126 and LY294002. Finally, the HB-EGF-induced activation of Akt and eNOS was suppressed by VEGF competitive antagonist, CBO-P11.
Answer: These results demonstrate that HB-EGF-induced eNOS activation depends on p42/p44 MAPK, PI3K/Akt pathways and endogenous VEGF in HaCaT cells.

Output: Do hB-EGF-induced VEGF production and eNOS activation depend on both PI3 kinase and MAP kinase in HaCaT cells?


Input: Consider Input: Context: After ingestion of phosphatidylcholine, l-carnitine or betaine, trimethylamine-N-oxide (TMAO) is formed by gut microbiota and liver enzymes. Elevated TMAO plasma levels were associated with increased cardiovascular risk and other diseases. Also betaine and choline itself were recently associated with increased cardiovascular risk.', 'A newly developed LC-HRMS method was applied to measure the plasma concentrations of TMAO, betaine and choline in a cohort of 339 patients undergoing coronary angiography for the evaluation of suspected coronary artery disease.', "Betaine concentrations in males were significantly higher than in females (42.0 vs. 35.9\xa0μmol/L; p\xa0<\xa00.001). Plasma concentrations of TMAO but not of betaine or choline were higher in patients with diabetes compared to euglycemic patients (2.39 vs. 0.980\xa0μmol/L; p\xa0=\xa00.001) as well as in patients with metabolic syndrome as compared to patients without metabolic syndrome (2.37 vs. 1.43\xa0μmol/L; p\xa0=\xa00.002). Plasma concentrations of TMAO or choline increased significantly with decreasing renal function (Spearman's rho:\xa0-0.281; p\xa0<\xa00.001). However, plasma levels of TMAO or betaine were associated with neither a history of myocardial infarction nor the angiographically assessed presence of coronary heart disease, nor incident cardiovascular events during 8 years of follow-up. Plasma levels of choline were significantly lower in patients with a history of acute myocardial infarction as compared to those without such history (10.0 vs. 10.8\xa0μmol/L; p\xa0=\xa00.045).
Answer: Plasma levels of TMAO are confounded by impaired kidney function and poor metabolic control but are not associated with the history, presence or incidence of symptoms or events of coronary heart disease.

Output: Are plasma levels of trimethylamine-N-oxide confounded by impaired kidney function and poor metabolic control?


Input: Consider Input: Context: Primary hyperparathyroidism, which occurs most commonly in patients with adenomatous disease of a single parathyroid gland, arises as a result of impaired extracellular Ca(2+) (Ca(2+)(o))-dependent feedback on PTH secretion, a process mediated by the calcium-sensing receptor (CaR).', 'Because the Ca(2+)(o) sensitivity of the CaR is positively modulated by L-amino acids, we decided to investigate whether the impaired feedback of PTH secretion in adenomatous parathyroid cells might arise from decreased sensitivity to L-amino acids.', 'Samples of normal and adenomatous human parathyroid cells were prepared by collagenase treatment and then exposed in vitro to various concentrations of Ca(2+)(o) or the CaR-active amino acid, L-phenylalanine (L-Phe).', 'Excess normal parathyroid tissue was obtained from parathyroid autotransplants at the time of thyroid surgery. Samples of adenomatous tissue were obtained from histologically confirmed parathyroid adenomas.', 'The primary measure was sensitivity of Ca(2+)(o)-dependent PTH secretion to the amino acid L-Phe. The secondary measure was sensitivity of Ca(2+)(o)-dependent intracellular Ca(2+) mobilization to L-Phe.', 'Parathyroid adenomas exhibited reduced sensitivity to the CaR-active amino acid L-Phe, which affected both Ca(2+)(o)-dependent PTH secretion and Ca(2+)(o)-dependent intracellular Ca(2+) mobilization as a measure of CaR-dependent signaling in parathyroid cells.
Answer: Impaired L-amino acid sensing by calcium-sensing receptors in adenomatous parathyroid cells contributes to the loss of feedback control of PTH secretion in primary hyperparathyroidism. The CaR's amino acid binding site may be exploited as a target in the medical treatment of primary and perhaps other forms of hyperparathyroidism.


Output: Do adenomatous human parathyroid cells exhibit impaired sensitivity to L-amino acids?