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.

Context: Lung transplantation is a viable option for patients with cystic fibrosis. The current strategy of selection, based on spirometry and deterioration of quality of life, results in a high mortality on the waiting list. We reviewed the case histories of patients with cystic fibrosis accepted for lung transplantation to ascertain whether pulmonary hemodynamics could contribute to predict life expectancy.', 'Forty-five patients with cystic fibrosis were accepted: 11 died on the waiting list (group I), 24 underwent transplantation (group II), and 10 are still waiting (group III). During evaluation we recorded spirometry, oxygen requirement, ratio of arterial oxygen tension to inspired oxygen fraction (PaO (2)/FIO (2)), arterial carbon dioxide tension (PaCO (2)), 6-minute walk test results, right ventricular ejection fraction, echocardiography, and pulmonary hemodynamics. We compared data from group I, II, and III patients. A comparison was also made within group II between the data collected at the time of evaluation and at the time of transplantation to quantify the deterioration during the waiting time.', 'The waiting time, spirometry, 6-minute walk test results, and right ventricular ejection fraction did not differ among the three groups. A statistically significant difference was found for PaO (2)/FIO (2), PaCO (2), mean pulmonary artery pressure, cardiac index, pulmonary arterial wedge pressure, and intrapulmonary shunt between groups I and II. Groups I and III showed statistically significant differences for mean pulmonary artery pressure, PaO (2)/FIO (2), and systemic vascular resistance indexed. No differences were observed between groups II and III. The comparison within group II showed a significant deterioration of pulmonary hemodynamics during the waiting time.
Answer: Pulmonary hemodynamics are worst in patients dying on the waiting list and deteriorate significantly during the waiting time. They may thus contribute to establish priority for lung transplantation in patients with cystic fibrosis.
Do pulmonary hemodynamics contribute to indicate priority for lung transplantation in patients with cystic fibrosis?

Context: We quantitatively evaluated the collagen-to-smooth muscle tissue matrix ratio in ureteropelvic junction obstruction, and compared the ratio with the degree of obstruction, patient age and postoperative renal recovery.', "We analyzed histological sections from 65 patients with ureteropelvic junction obstruction and 6 normal controls. Morphological and functional grading systems were adapted to determine the degree of renal obstruction. To examine smooth muscle and collagen tissue, sections were stained using Masson's trichrome. Two distinct populations of collagen versus smooth muscle were identified and the tissue matrix ratio was calculated by color image analysis.", 'The mean tissue matrix ratio plus or minus standard deviation was 1.32+/-0.79 in all patients with ureteropelvic junction obstruction but only 0.30+/-0.10 in normal controls (p <0.0001). It appeared that the lower the tissue matrix ratio, the better the improvement in postoperative hydronephrosis (r = -0.50, p = 0.0001). Better recovery of renal function after pyeloplasty was observed with a decrease in the tissue matrix ratio (r = -0.43, p = 0.0004). We divided patients according to the tissue matrix ratio into groups 1--ratio 1 or less, 2--greater than 1 to 1.5 and 3--greater than 1.5 to determine a more detailed and clinically applicable correlation of tissue matrix ratio with postoperative renal functional changes. Better improvement in postoperative renal function was observed in group 1 than in group 3 (p = 0.002). Also, the tissue matrix ratio increased with patient age (r = 0.33, p = 0.007).
Answer: Since our data represent an objective and quantitative parameter associated with ureteropelvic junction obstruction, we believe that our findings may help to predict the prognosis after pyeloplasty.
Does collagen-to-smooth muscle ratio help prediction of prognosis after pyeloplasty?

Context: Vascular endothelial growth factor (VEGF) is a multifunctional cytokine that plays a role in angiogenesis and microvascular permeability. This study was conducted to determine whether common sequence variation in the VEGFA gene plays a role in the development of diabetic retinopathy (DR).', 'Five hundred fifty-four subjects with diabetes mellitus (DM) including 190 type 1 DM (T1DM) and 364 type 2 DM (T2DM) were recruited. The study group consisted of 235 participants without DR, 158 with nonproliferative DR (NPDR), 132 with proliferative DR (PDR), and 93 with clinically significant macular edema (CSME). Blinding DR was defined as severe NPDR, PDR, or CSME. Fifteen VEGFA tag single-nucleotide polymorphisms (SNPs) were genotyped in all subjects and tested for association with blinding DR.', 'Multiple tag SNPs in the VEGFA gene were associated with blinding DR. After controlling for sex, HbA1c, and duration of disease, in T1DM, the AA genotype of rs699946 (P = 0.007, odds ratio [OR], 4.1; 95% confidence interval [CI], 1.5-11.4) and the GG genotype of rs833068 (P = 0.017, OR, 3.1; 95% CI, 1.3-7.2) were most significantly associated. In T2DM, the C allele of rs3025021 (P = 0.002; OR, 3.8; 95% CI, 1.5-10.0) and the G allele of rs10434 (P = 0.002; OR, 2.6; 95% CI, 1.3-5.3) were most significantly associated with blinding DR. Haplotype analyses suggested an important role for the haplotype TCCGCG in blinding DR (P = 0.0004).
Answer: Sequence variation in the VEGFA gene is associated with risk of developing blinding DR in T1DM and T2DM. Identifying specific genetic markers will allow for refined screening algorithms and earlier intervention in patients at highest risk.

Does common sequence variation in the VEGFA gene predict risk of diabetic retinopathy?