Given a passage, 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.

Input: Consider Input: Pigs are frequently used as animal models in experimental medicine. To identify processes of vascular development or regression, vascular elements must be recognised and quantified in a three-dimensional (3D) arrangement. Vascular corrosion casts enable the creation of 3D replicas of vascular trees. The aim of our study was to identify suitable casting media and optimise the protocol for porcine liver vascular corrosion casting.', 'Mercox II®️ (Ladd Research, Williston, Vermont, USA) and Biodur E20®️ Plus (Biodur Products, Heidelberg, Germany) were tested in 4 porcine livers. The resins (volume approximately 700 mL) were injected via the portal vein. Corrosion casts were examined by macro-computed tomography, micro-computed tomography and scanning electron microscopy.', 'For hepatectomies, the operating protocol was optimised to avoid gas or blood clot embolisation. We present a protocol for porcine liver vascular bed casting based on corrosion specimens prepared using Biodur E20®️ epoxy resin.

Output: Does porcine liver vascular bed in Biodur E20 corrosion cast?

Input: Consider Input: Our objective was to study the direct effects of meconium on isolated umbilical artery and vein in vitro.', "Intact umbilical artery and vein rings were suspended in 5 ml organ baths containing kreb's solution (pH 7.2, 37 degrees C; bubbled with 2.5% oxygen and 8.07% carbon dioxide, balance nitrogen) for isometric tension recording. Meconium alone (final bath concentration 1%), centrifuged and filtered meconium, and meconium with the lipid fraction removed (separated into < 30,000 kd and > 30,000 kd) were added to the baths. Some vessels were also incubated in 1% meconium for 30 minutes, after which the meconium was washed out. Concentration-response curves to U46619 were obtained. The negative log of the concentration that evokes 50% of the maximal contraction was determined.", 'Umbilical artery and vein had no sustained response to meconium. Tension that developed by rings exposed to meconium was significantly less than control at all concentrations of U46619. There was some loss of the efficacy of meconium after centrifugation-filtration and washing out. Meconium without the lipid fraction had less inhibitory effect than did native meconium.

Output: Does meconium inhibit the contraction of umbilical vessels induced by the thromboxane A2 analog U46619?

Input: Consider Input: Ulcerative colitis (UC) is a chronic inflammatory intestinal disease. It is necessary to find out new effective drugs for UC. In our study epicatechin extracted from grape seed by our institute for the first time could treat UC effectively. Then anti-UC mechanisms of epicatechin were elucidated in vivo and in vitro.', 'Dextran sulfate sodium (DSS)-induced acute UC mice model was used to evaluate the activity of epicatechin and its properties against UC. Then its anti-inflammatory and antioxidant effects were evaluated as follows: the concentrations of TNF- and IL-6 in the colon supernatants were determined by ELISA. NO and MPO were assayed by Griess method and commercial kit respectively. NF-B were determined by NF-B-Dependent Reporter Gene Expression Assay and Western Blotting respectively. Antioxidant factors such as SOD, MDA, GSH-Px and CAT were also measured in colon tissues and cell supernatant stimulated by LPS respectively.', 'In C57BL/6J mice model with DSS-induced UC, epicatechin was able to decrease the disease activity index and colon macroscopic damage index scores, reduce body weight loss, and significantly relieve colon contracture and crypt damage. TNF-, IL-6, NO, MPO and MDA were reduced in the mice administered epicatechin, whereas antioxidant enzymes showed increased activity in epicatechin-treated mice and cell line respectively. Furthermore, inhibition effect on NF-B activation by epicatechin were demonstrated in vivo and in vitro.
Output: Is the protective effect of epicatechin on experimental ulcerative colitis in mice mediated by increasing antioxidation and by the inhibition of NF-B pathway?