In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.

Ex Input:
Context: Halofuginone is a novel antifibrotic agent that can reverse the fibrotic process by specific inhibition of collagen type I synthesis.', 'To evaluate the effect of Halo on the development of glomerulosclerosis and interstitial fibrosis in the 5/6 nephrectomy rat model', 'Male Wistar rats were assigned to undergo 5/6 NX or sham operation, and then divided into three groups: 5/6 NX rats (NX-Halo and NX-Control) and sham. Systolic blood pressure, proteinuria and body weight were determined every 2 weeks. At sacrifice (10 weeks) creatinine clearance was evaluated and remnant kidneys removed for histologic examination, sirius red staining and in situ hybridization', 'Systolic blood pressure increased progressively in both 5/6 NX groups. Halo slowed the increase in proteinuria in 5/6 NX rats. As expected, creatinine clearance was lower in 5/6 NX groups when compared to sham rats. Creatinine clearance was significantly higher in the NX-Halo group at the end of the study period. Histologic examination by light microscopy showed significantly less severe interstitial fibrosis and glomerulosclerosis in Halo-treated rats. The increase in collagen alpha1 (I) gene expression and collagen staining after nephrectomy was almost completely abolished by Halo.\Question: Does halofuginone reduce the occurrence of renal fibrosis in 5/6 nephrectomized rats?

Ex Output:
Halofuginone reduced proteinuria as well as the severity of interstitial fibrosis and glomerulosclerosis in 5/6 NX rats. The renal beneficial effect of Halo was also demonstrated by the blunted decrease in creatinine clearance observed in the treated animals.

Ex Input:
Context: To find permanent prostate implant (PPI) pre-plan dosimetric parameters that predict post-implant D90 140 Gy.', 'Pre-plans were evaluated for 504 patients undergoing PPI with (125)I seeds for low or intermediate risk prostate cancer. Baseline patient and disease factors, numbers of seeds, ratios of number of seeds to available positions (occupancy proportion), and distances between the 100% isodose line and edge of the prostate (margin) planned for the whole prostate (WP), superior (S), inferior (I), anterior (A), and posterior (P) halves, SA, SP, IA, and IP quarters, and superior (ST), inferior (IT), and middle (MT) thirds, and anterior (AT) and posterior (PT) middle one-sixth segments were analyzed by post-implant D90 subset ( 140 Gy vs. < 140 Gy).', '20% had post-implant D90 < 140 Gy (mean: 128.0 Gy, range: 97.5-139.2) vs. 140 Gy (mean: 154.4 Gy, range: 140.0-193.5). The D90 140 Gy subset had larger AT and IA segment mean numbers of seeds (p = 0.01, 0.046), larger WP, S, A, SA, ST, AT, and MT segment mean margins (p = 0.01, 0.01, 0.001, 0.0001, 0.03, 0.005, 0.02), and lower PT segment occupancy proportion (p = 0.004). On multivariate analysis, independent predictors of post-implant D90 140 Gy were increased SA mean margin, no pre-implant 5--reductase inhibitor, higher pre-plan D90, decreased P occupancy proportion, no pre-implant hormone therapy, and decreased SP mean margin.\Question: Do pre-plan parameters predict post-implant D90 140 Gy for ( 125 ) I permanent prostate implants?

Ex Output:
Higher occupancy proportion and larger margins anteriorly and reduced occupancy proportion, and smaller margins posteriorly on PPI pre-plans predict post-implant D90 140 Gy.

Ex Input:
Context: Oral submucous fibrosis is a pre-malignant fibrotic condition caused by areca nut use and involves reduced mucosal vascularity. Arecoline is the principal areca nut alkaloid and is cytotoxic for epithelium and fibroblasts. Endothelial cell cycle arrest is reported on exposure to arecoline, as is cytotoxicity for endothelial-lung carcinoma hybrid cells. We here describe cytotoxicity for primary human endothelial cultures from seven separate donors.', 'Human umbilical vein endothelial cells were exposed to increasing concentrations of arecoline and examined by: phase-contrast microscopy, haemocytometer counts, transmission electron microscopy, lactate dehydrogenase release and the methyl-thiazol-tetrazolium assay.', 'Vacuolation and detachment of endothelium were observed at and above arecoline concentrations of 333g/ml or more. Ultrastructural features of cellular stress were seen after 24-h treatment with 111g/ml arecoline and included reduced ribosomal studding of endoplasmic reticulum, increased autophagolysosomal structures, increased vacuolation and reduced mitochondrial cristae with slight swelling. Similar changes were seen at 4h with arecoline at 333g/ml or above, but with more severe mitochondrial changes including increased electron density of mitochondrial matrix and greater cristal swelling, while by 24h, these cells were frankly necrotic. Haemocytometer counts were paralleled by both lactate dehydrogenase release and the methyl-thiazol-tetrazolium assays.\Question: Is arecoline cytotoxic for human endothelial cells?

Ex Output:
Arecoline is cytotoxic via necrosis for endothelium, while biochemical assays indicate no appreciable cellular leakage before death and detachment, as well as no clear effect on mitochondrial function in viable cells. Arecoline toxicity may thus contribute to reduced vascularity in oral submucous fibrosis.