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.
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Question: 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.

Answer: Does collagen-to-smooth muscle ratio help prediction of prognosis after pyeloplasty?


Question: Context: A number of gene therapy applications would benefit from vectors capable of expressing multiple genes. In this study we explored the feasibility and efficiency of expressing two or three transgenes in HIV-1 based lentiviral vector. Bicistronic and tricistronic self-inactivating lentiviral vectors were constructed employing the internal ribosomal entry site (IRES) sequence of encephalomyocarditis virus (EMCV) and/or foot-and-mouth disease virus (FMDV) cleavage factor 2A. We employed enhanced green fluorescent protein (eGFP), O6-methylguanine-DNA-methyltransferase (MGMT), and homeobox transcription factor HOXB4 as model genes and their expression was detected by appropriate methods including fluorescence microscopy, flow cytometry, immunocytochemistry, biochemical assay, and western blotting.', 'All the multigene vectors produced high titer virus and were able to simultaneously express two or three transgenes in transduced cells. However, the level of expression of individual transgenes varied depending on: the transgene itself; its position within the construct; the total number of transgenes expressed; the strategy used for multigene expression and the average copy number of pro-viral insertions. Notably, at limiting MOI, the expression of eGFP in a bicistronic vector based on 2A was approximately 4 times greater than that of an IRES based vector.
Answer: The small and efficient 2A sequence can be used alone or in combination with an IRES for the construction of multicistronic lentiviral vectors which can express encoded transgenes at functionally relevant levels in cells containing an average of one pro-viral insert.

Answer: Do multicistronic lentiviral vectors containing the FMDV 2A cleavage factor demonstrate robust expression of encoded genes at limiting MOI?


Question: Context: To determine the role of recipient lymphopenia state in the expansion and function of leukemia specific cytotoxic T lymphocytes (CTLs).', 'C57BL/6 mice were induced to lymphopenia with 6 Gy total body irradiation. Spleen T cells or leukemia specific T cells from EGFP+ transgenic C57BL/6-EGFP mice were adoptively transferred by intravenous injection. The mice were challenged subcutaneously with 1 x 10(6) FBL3 leukemic cells at day 2 after irradiation. The peripheral WBC count, percentage of EGFP+ cells, subsets of T cells and tumor sizes were monitored.', 'Both of the spleen T cell and leukemia specific CTL proliferated efficiently with the percentage of EGFP+ cells of 28. 81% and 42.24%, respectively, after infused into lymphopenic recipients. However, spleen T cells had no anti-leukemia effect regardless of its expansion. In contrast, leukemia specific CTLs showed a more rapid and extensive expansion under the condition of lymphopenia and a enhanced anti-leukemia immunity.
Answer: Transfusion of leukemia specific CTLs under lymphopenia state could be a feasible strategy to expand leukemia specific CTLs and generate favorable anti-leukemia effect in vivo.

Answer:
Does [ Recipient lymphopenia state enhance the expansion and anti-leukemia effect of leukemia specific cytotoxic T lymphocytes ]?