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: Transcatheter aortic valve implantation (TAVI) without predilatation has fewer procedural steps and thereby potentially fewer complications. This has been demonstrated for the antegrade transapical access; however, whether TAVI can be safely performed without predilatation using the retrograde transfemoral route is unknown.', 'We postulated that TAVI is feasible with a balloon-expandable device without predilatation using the retrograde transfemoral route.', 'Twenty-six consecutive patients with stenosis of the native aortic valve (AV) undergoing transfemoral TAVI with the Edwards SAPIEN XT prosthesis without predilatation were enrolled in this retrospective study and compared with 30 patients treated previously with predilatation.', 'The procedure was successfully performed in all 26 patients, irrespective of the AV area and the extent of AV calcification. At baseline mean AV area, mean AV gradient, and median left ventricular ejection fraction were 0.7 0.2 cm(2) , 36.0 17.3 mm Hg, and 55.0% (interquartile range [IQR], 35.0-60.0], respectively; prior to discharge these values were 1.7 0.3 (P < 0.001), 9.8 6.1 mm Hg (P < 0.001), and 57.5% (IQR, 38.7-60.0) (P = not significant). Postdilatation was required in 3 patients due to aortic regurgitation > 2; this was reduced by the procedure to < 2 in all cases. Radiation dose and amount of contrast dye were significantly reduced in comparison with the predilatation group. No periprocedural neurological adverse events occurred. Mortality at 30 days was 0%.
Answer: TAVI without predilatation using the transfemoral Edwards SAPIEN XT valve is feasible and safe. Larger studies are required to further evaluate this approach.
[A]: Is transfemoral aortic valve implantation of Edwards SAPIEN XT without predilatation feasible?

[Q]: Context: The interaction between Siglec-10 and its ligand, CD24, selectively represses tissue damage-caused immune responses. However, the nature of Siglec-10 and CD24 in human hepatocellular carcinoma (HCC) is still poorly defined. Hereon, the expression, function, and regulation of CD24 and Siglec-10 in HCC were investigated in the present study.', 'Flow cytometry was performed to examine the expression of Siglec-10 in HCC tissues and adjacent non-tumor tissues of HCC patients. To further determine whether Siglec-10 expression is associated with the clinical characteristics and survival, conventional immunohistochemistry was performed in 96 HCC patients. Additionally, the role of Siglec-10 in the regulation of natural killer (NK) cell dysfunction was evaluated. Finally, CD24 expression in HCC was also assessed.', 'Siglec-10 was expressed most on NK cells in HCC (40.7 4.5%). Compared with surrounding non-tumor tissues, tumor tissues had higher Siglec-10 expression (31.0 1.7% versus 40.7 4.5%, n = 10, P < 0.05), and the expression was negatively associated with patient survival. Siglec-10(+)CD56(+) NK cells exhibited reduced effector function, as shown by decreased granules and cytokine expressions compared with Siglec-10(-)CD56(+) NK cells. Moreover, the number of CD24(+)CD45(-) cells in HCC tissues was higher than that in adjacent non-tumor tissues (9.4 0.9% versus 3.1 0.9%, n = 15, P < 0.05).
Answer: These findings suggest that Siglec-10 is associated with decreased survival and impaired NK cell function in human HCC. This process may function via the CD24-Siglec-10 interaction, which may represent a therapeutic target in HCC patients.
[A]: Is siglec-10 associated with survival and natural killer cell dysfunction in hepatocellular carcinoma?

[Q]: Context: Research on olfactory G-protein coupled receptors (GPCRs) has been severely impeded by poor functional expression in heterologous systems. Previously, we demonstrated that inefficient olfactory receptor (OR) expression at the plasma membrane is attributable, in part, to degradation of endoplasmic reticulum (ER)-retained ORs by the ubiquitin-proteasome system and sequestration of ORs in ER aggregates that are degraded by autophagy. Thus, experiments were performed to test the hypothesis that attenuation of ER degradation improves OR functional expression in heterologous cells.', 'To develop means to increase the functional expression of ORs, we devised an approach to measure activation of the mOREG OR (Unigene # Mm.196680; Olfr73) through coupling to an olfactory cyclic nucleotide-gated cation channel (CNG). This system, which utilizes signal transduction machinery coupled to OR activation in native olfactory sensory neurons, was used to demonstrate that degradation, both by the ubiquitin-proteasome system and autophagy, limits mOREG functional expression. The stimulatory effects of proteasome and autophagy inhibitors on mOREG function required export from the ER and trafficking through the biosynthetic pathway.
Answer: These findings demonstrate that poor functional expression of mOREG in heterologous cells is improved by blocking proteolysis. Inhibition of ER degradation may improve the function of other ORs and assist future efforts to elucidate the molecular basis of odor discrimination.
[A]:
Does endoplasmic reticulum degradation impede olfactory G-protein coupled receptor functional expression?