TASK DEFINITION: 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.
PROBLEM: Context: Is a perioperative metastatic screening programme indicated in patients presenting with primary operable breast cancer and no signs of distant metastases?', 'The impact of staging results (chest X-ray, bone scanning, liver ultrasound) for prognosis, treatment, quality of life and costs was retrospectively analysed in 1 076 patients with an operable breast cancer and no clinical signs of metastases.', 'Staging examinations revealed 30 (2.8 %) distant metastases, 130 (12.1 %) suspect findings and excluded metastases in 916 (85.1 %) patients. Further diagnostic procedures confirmed distant metastases in 7 (5.4 %) and excluded them in 123 (94.6 %) out of 130 patients with suspect findings. Distant metastases were detected more frequently with increasing tumor size (pT < or = 2.0 cm: 1.6 %, pT 2.1-5.0 cm: 3.0 %, respectively pT > 5.0 cm: 15.1 %; p < 0.001) and increasing number of involved axillary lymph nodes (pN0: 1.4 %, pN1-3 +: 1.8 %, pN4-9 +: 4.0 %, pN > 10 +: 12.5 %; p < 0.001). Due to false positive findings 123 (11.4 %) patients had to live for a significant period of time with the psychological distress of suspected metastatic disease. The abandonment of a perioperative screening in 1 076 patients saves costs of at least euro 259,366.68.
Answer: In breast cancer patients without clinical signs of tumor spread perioperative screening for metastases is not warranted because of low frequency of metastases, false positive findings, missing therapeutic consequences and high costs.

SOLUTION: Is [ A perioperative screening for metastatic disease indicated in patients with primary breast cancer and no clinical signs of tumor spread ]?

PROBLEM: Context: Pulmonary vein (PV) isolation is a curative treatment for patients with atrial fibrillation. The aim of this study was to evaluate prospectively the effects of adenosine administration on the PV activity and atrio-venous conduction after PV isolation.', 'Twenty-nine patients (21 m; age: 55+/-8 years) were submitted to ostial PV isolation guided by basket catheter recordings. After successful isolation, the effects of a 12 mg intravenous bolus of adenosine were tested in 62 PVs. In 22/62 PVs (35%), left atrium (LA)-to-PV conduction was transiently (16.6+/-7.1 s, range: 3.8-27.9 s) or permanently (3 PVs) restored in response to adenosine administration. The prevalence of this phenomenon was 39% in left superior PVs, 43% in right superior PVs, and 22% in left inferior PVs (p=0.365). It occurred more frequently in the presence of dissociated PV activity (11/15 PVs, 73% vs. 11/47 PVs, 23%; p=0.002), whereas it was not influenced by the median duration of the radiofrequency current (RFC) delivery for each PV [19 (IQR: 12-26) min vs. 16 (IQR: 11-24) min: p=0.636]. A lengthening or shortening of the LA-PV conduction time was observed at LA-PV conduction appearance and disappearance in 36% and 55% of the cases, respectively. Further RFC applications (median: 5.5 min, IQR: 4-11 min) at the residual conduction breakthrough(s) indicated by the basket catheter recordings definitively eliminated adenosine-induced recovery of LA-PV conduction in all cases. Finally, when present, intrinsic PV discharge was invariably depressed by adenosine administration.
Answer: Adenosine may transiently or permanently re-establish LA-PV conduction after apparently successful PV isolation. This phenomenon is abolished by additional RFC delivery. However, its possible influence on the clinical results of PV ablation must be evaluated by properly designed, randomized studies.

SOLUTION: Does adenosine restore atrio-venous conduction after apparently successful ostial isolation of the pulmonary veins?

PROBLEM: Context: To study if spontaneous contractions augmented by proteinase-activated receptor-2 (PAR-2)-activating peptide serine-leucine-isoleucine-glycine-arginine-leucine (SLIGRL) involve coactivation of membrane chemoceptors and are associated with expression of PAR-2 mRNA in non-pregnant and pregnant rat myometrium.', "Non-pregnant, mid-pregnant, and late pregnant rat uterine horn and small intestine segments were snap-frozen in liquid nitrogen to determine PAR-2 mRNA levels by real time polymerase chain reaction (PCR). Uterine rings were used for isometric tension recording. Effect of SLIGRL (0.1 mM) on spontaneous contractions before and after exposure to ibuprofen (cyclooxygenase inhibitor, 1.0 microM), SQ-29548 (thromboxane A(2) receptor inhibitor, 1.0 microM), ketotifen (histamine 1 receptor inhibitor, 10 microM), WEB-2170BS (platelet-activating factor (PAF) receptor inhibitor, 10 microM), atropine (muscarinic receptor inhibitor, 0.1 microM), or ketanserin (serotonin receptor inhibitor, 10 microM) were compared. Paired t-test and one-way ANOVA followed by Dunnett's or Newman-Keuls post hoc tests were used for statistical analysis when appropriate.
Answer: P<0.05.

SOLUTION:
Does pAR-2 activating peptide-induced stimulation of pregnant rat myometrium contractile activity partly involve the other membrane receptors?