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: 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: This study was designed to evaluate the effects of a dorzolamide-timolol combination or dorzolamide on retinal ganglion cell (RGC) density and intraocular pressure (IOP) in glaucomatous eyes of adult rats.', 'Glaucoma was induced in the right eye of adult Wistar rats by episcleral venous occlusion. One experimental group was administered dorzolamide 2%-timolol 0.5% combination eye drops, while the other experimental group was administered dorzolamide 2% eye drops. Control groups had surgery without drug administration. Drug application was initiated either 2 weeks before surgery (Group A), from the day of surgery (Group B), 2 weeks after surgery (Group C), or 4 weeks after surgery (Group D). RGCs were labeled by intratectal Fluorogold injections and counted from flat-mount preparations, and IOP was measured using Tonopen.', 'Both dorzolamide-timolol combination and dorzolamide, when applied topically, significantly reduced IOP and improved RGC densities in experimental eyes when compared to control eyes. Earlier initiation, as well as longer duration of drug application, resulted in higher RGC densities.
Answer: Topical application of a dorzolamide-timolol combination or dorzolamide saved RGCs to a significant extent and reduced IOP in glaucomatous rat eyes.
Does dorzolamide and timolol save retinal ganglion cells in glaucomatous adult rats?

Context: To determine the relationship between preoperative catecholamine levels and intraoperative peak plasma lactate levels in patients who underwent adrenalectomy for pheochromocytoma.', 'Retrospective observational study.', 'Operating room in one university hospital.', 'The records of 27 ASA physical status 1 and 2 patients who underwent adrenalectomy for pheochromocytoma were studied. Preoperative catecholamine levels and intraoperative plasma lactate levels were recorded.', "Twenty cases had high lactate levels (>2 mmol/L). Preoperative urine epinephrine levels and urine metanephrine levels showed a moderate correlation with intraoperative peak plasma lactate levels (rs = 0.475 and rs = 0.499, respectively; Spearman's rank correlation test). Receiver operating characteristic (ROC) curve analysis for preoperative urine epinephrine levels showed good performance for prediction of high lactate levels [>2 mmol/L, area under the curve (AUC) =0.800], whereas ROC for preoperative urine norepinephrine levels showed no predictive performance for high lactate levels.
Answer: Catecholamine release caused by surgical manipulation may be a possible cause of intraoperative transient lactic acidosis, and it should be considered as a differential diagnosis of intraoperative lactic acidosis. Intraoperative peak plasma lactate level was correlated with preoperative epinephrine-releasing activity.
Does catecholamine release induce elevation in plasma lactate levels in patients undergoing adrenalectomy for pheochromocytoma?