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.

Example Input: Context: Impaired neurodevelopmental outcome represents a major morbidity for survivors of infant heart surgery for congenital heart defects. Previous studies in these neonates have reported preoperative microcephaly, periventricular leukomalacia, and other findings. The hypothesis of this study is that preoperative cerebral blood flow is substantially diminished and might relate to preoperative neurologic conditions.', 'Preoperative brain magnetic resonance imaging was performed. Cerebral blood flow measurements in infants with congenital heart defects were obtained by using a novel noninvasive magnetic resonance imaging technique, pulsed arterial spin-label perfusion magnetic resonance imaging. Cerebral blood flow was measured before the operation under standard ventilation and repeated after increased carbon dioxide.', 'A total of 25 term infants were studied. The average age at the time of the operation was 4.4 +/- 4.6 days. Congenital heart defects varied widely. Microcephaly occurred in 24% (6/25). Baseline cerebral blood flow was 19.7 +/- 9.2 mL . 100 g -1 . min -1 (8.0-42.2 mL . 100 g -1 . min -1 ). Five patients had cerebral blood flow measurements of less than 10 mL . 100 g -1 . min -1 . Mean hypercarbic cerebral blood flow increased to 40.1 +/- 20.3 mL . 100 g -1 . min -1 (11.4-94.0 mL . 100 g -1 . min -1 , P < .001). Pairwise analyses found that low hemoglobin levels were associated with higher baseline cerebral blood flow values ( P = .04). Periventricular leukomalacia occurred in 28% (7/25) and was associated with decreased baseline cerebral blood flow values ( P = .05) and a smaller change in cerebral blood flow with hypercarbia ( P = .003).
Answer: Structural brain abnormalities are common in these neonates before surgical intervention. Preoperative cerebral blood flow for this cohort was low and drastically reduced in some patients. Low cerebral blood flow values were associated with periventricular leukomalacia. Carbon dioxide reactivity was preserved but might be compromised by some aspects of the cardiac anatomy. The full spectrum of cerebral blood flow measurements with this technique in congenital heart defects and their long-term significance require continued investigation.
Example Output: Is preoperative cerebral blood flow diminished in neonates with severe congenital heart defects?

Example Input: Context: Barrett esophagus (BE) is considered precursor condition of esophageal adenocarcinoma. Its incidence and prevalence are increasing in general population. Studies reported that metabolic syndrome (MS) or diabetes mellitus (DM) is related to increased risk of BE. Current study was to assess and better understand the relationship between MS /DM and BE.', "Electronic search was conducted in the database Pubmed/Medline (-December, 2015), Embase (-December, 2015), Cochrane Library (-December, 2015), and Web of Knowledge (-December, 2015). Studies included were assessed with summary odds ratios (ORs) with 95% confidence intervals (CIs) and compared exposure group with control group. The heterogeneity was examined by the funnel plot and the Egger's test. Subgroup analyses and sensitive analyses were performed for the detection of possible heterogeneity and impact on stability of analysis results.", "Twelve publications met the criteria and included 355,311 subjects were analyzed. The pooled results showed MS was closely associated with increased risk of BE (OR\u200a=\u200a1.23; 95%CI 1.03-1.47; P\u200a=\u200a0.024), and yet DM did not significantly increase the risk of BE (OR\u200a=\u200a1.07; 95%CI 0.82-1.38; P\u200a=\u200a0.627). Substantial heterogeneities were detected. No significant publication bias was detected by Egger's test (P\u200a=\u200a0.23).
Answer: Based on the results of current meta-analysis, MS is associated with increased risk of BE. Further long-term follow-up prospective study needs to verify the current results, and definite pathophysiological mechanism needs to be further investigated and clearly elucidated.
Example Output: Is metabolic syndrome associated with increased risk of Barrett esophagus : A meta-analysis?

Example Input: Context: To explore the protective effect of the Phyllanthus Urinaria (PU) extract on the N-cadherin expression in the testicular tissues disrupted by nitrogen mustard (HN2) in vivo.', 'HN2 was intraperitoneally injected into male KM mice at the dose of 5 mg/kg to make reproductive toxicity models, and at the same time PU was administered for intervention at the dose of 125 mg/kg, 250 mg/kg and 500 mg/kg. N-cadherin distribution, mRNA and protein expression in the testicular tissues were detected by immunohistochemistry, RT-PCR and Western blotting.', 'N-cadherin was mainly distributed in the membrane and cytoplasm of Sertoli cells at the basement of seminiferous epithelia, Leydig cells and peritubular cells, scarcely expressed in the basement of seminiferous epithelia and peritubular cells after HN2 administration. The expressions of mRNA and proteins of N-cadherin were significantly elevated with the increased dose of PU (P < 0.01). Compared with the normal control, the distribution and expression of N-cadherin showed no significant differences in either the high-dose PU group or the HN2 with high-dose PU intervention group (P > 0.05).
Answer: The PU extract can effectively promote the N-cadherin expression in the testis tissues disrupted by HN2.
Example Output:
Does [ Phyllanthus urinaria extract promote N-cadherin expression in nitrogen mustard-disrupted testicular tissues in vivo ]?