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.

Q: 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.

A: Does adenosine restore atrio-venous conduction after apparently successful ostial isolation of the pulmonary veins?
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Q: Context: Cytotechnologists and pathologists often perform onsite evaluations of thyroid fine-needle aspirations (FNAs) to provide immediate feedback regarding whether adequate material has been obtained for cytologic diagnosis. The current study was designed to determine whether onsite adequacy assessment results in a significant decrease in nondiagnostic specimens between ultrasound (US)-guided FNAs of the thyroid and those performed by palpation alone.', 'A search was performed to identify in-house thyroid FNAs performed between January 1, 2000 and December 31, 2003 that were obtained under US guidance or by palpation only. It was then recorded whether an onsite adequacy assessment was performed. The submitting physician and final diagnosis also were recorded for each case. Contingency tables were constructed and evaluated using chi-square analysis.', 'Of 1502 in-house thyroid FNAs included in the current study, 981 (65.3%) were performed under US guidance and 521 (34.7%) were performed with palpation alone. Onsite adequacy assessment of the aspirated material was performed in 323 cases (21.5%), whereas 1179 cases (78.5%) were performed without onsite evaluation. Of the 418 palpation-guided FNAs that were performed without adequacy assessment, 70 (16.7%) were reported to be nondiagnostic, whereas of the 103 palpation-guided FNAs with immediate evaluation, only 7 (6.8%) were determined to be inadequate for diagnosis. This difference was statistically significant (P < 0.025). Of 761 US-guided FNAs without immediate adequacy assessment, 54 (7.1%) were nondiagnostic, which was not statistically different from the nondiagnostic rate of 4.5% (10 of 220 cases) for US-guided FNAs with onsite evaluation. However, when these US-guided FNAs were divided further into 2 groups based on the experience of the radiologist performing the FNA, the nondiagnostic rate in the group of experienced radiologists was only 5.4% (or 32 of 592 US-guided FNAs), even though onsite evaluation was not performed. Among radiologists with less experience, adequacy assessment significantly reduced the nondiagnostic rate from 13.0% (22 of 169 FNAs without adequacy assessment) to 4.5% (10 of 220 FNAs with adequacy assessment) (P < 0.01).
Answer: The results of the current study demonstrate that onsite adequacy assessment of thyroid FNAs significantly reduces the number of nondiagnostic aspirates. However, the benefit of onsite evaluation, at least for US-guided FNAs, depends on the experience of the radiologist. In the current study, experienced radiologists with a relatively low nondiagnostic rate did not benefit from onsite adequacy assessment. This finding confirms the importance of experience in the performance of FNA, but suggests that onsite adequacy assessment may assist the less experienced operator.

A: Is the value of onsite adequacy assessment of thyroid fine-needle aspirations a function of operator experience?
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Q: Context: Local invasion is a common pattern of spread in uterine cervical squamous cell carcinoma (CSCC). Although transforming growth factor-beta (TGF-β) facilitates invasion of various types of cancer cells, the role of the TGF-β pathway in CSCC is unclear. In this study, we analyzed the role of TGF-β signaling in the progression of CSCC.', 'Immunohistochemistry was used to examine the expression of TGF-β pathway molecules in 67 CSCC samples with clinicopathological data. Activation of the TGF-β pathway was investigated following co-culture of CSCC cells and cervical cancer-associated fibroblasts (CCAFs).', 'Clinicopathological analysis of CSCC samples revealed that prominent expression of TGF-β receptor-2 was more frequent in CSCC with lymphovascular space invasion (LVSI) than without LVSI (p < 0.01). Lymph node metastasis was more frequent in cases in which phosphorylated SMAD3 (pSMAD3) was localized exclusively at the boundary of tumor clusters (n = 9, p < 0.05). Recombinant TGF-β1 increased pSMAD3 expression and enhanced cellular invasion (p < 0.005) in CSCC cells, which was attenuated by an inhibitor of the TGF-β receptor (p < 0.005). Enhanced pSMAD3 expression and invasion was also observed when conditioned media from CSCC cells co-cultured with CCAFs were administered. Luciferase assays showed that this medium contained a large amount of active TGF-β. Along with TGF-β activation, thrombospondin-1 was upregulated in both CSCC cells and CCAFs, while thrombospondin-1 silencing in either CSCC cells or CCAFs repressed the activity of TGF-β. Thrombospondin-1 was prominently expressed in cases with pSMAD3 boundary staining (p < 0.05).
Answer: These results suggest that interaction between CSCC cells and surrounding CCAFs activates TGF-β via thrombospondin-1 secretion to facilitate CSCC invasion.

A:
Is invasion of uterine cervical squamous cell carcinoma cells facilitated by locoregional interaction with cancer-associated fibroblasts via activating transforming growth factor-beta?
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