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.
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Question: Polo-like kinase 1 (PLK1) controls the main cell-cycle checkpoints, suggesting utility of its inhibition for cancer treatment, including of highly proliferative pediatric cancer. This preclinical study explored the selective PLK1 inhibitor volasertib (BI 6727) alone and combined with chemotherapy in pediatric malignancies.', 'Inhibition of proliferation was explored in vitro using dimethylthiazol carboxymethoxyphenyl sulfophenyl tetrazolium (MTS) assay. Mice bearing human xenografts were treated with weekly intravenous injections of volasertib.', 'Volasertib inhibited proliferation in all 40 cell lines tested, with a mean half-maximal growth inhibitory concentration of 313 nmol/l (range: 4-5000 nmol/l). Volasertib was highly active against RMS-1 alveolar rhabdomyosarcoma xenografts, resulting in 100% tumor regression. Activity was associated with complete and prolonged G2/M arrest and subsequent apoptotic cell death. Volasertib showed synergistic activity with vincristine but antagonistic effects with etoposide.

Answer: Does polo-like Kinase Inhibitor Volasertib exhibit Antitumor Activity and Synergy with Vincristine in Pediatric Malignancies?

Question: The main objective of this study was to analyse the outcomes after total knee arthroplasty (TKA) of a group of patients with at least one self-reported allergy and a group of patients without reported allergies. We hypothesized there is a significant negative influence on clinical outcome scores after TKA in patients with self-reported allergies.', "Four-hundred and seventy-five patients who had undergone TKA were analysed preoperatively and 1year after surgery. The WOMAC, KSS and SF-36 scores were obtained. The patients' Yesavage depression questionnaire score was also recorded. The scores of the 330 (69.5%) patients without self-reported allergies were compared to the scores of the 145 (30.5%) patients with at least one self-reported allergy in the medical record.", 'Preoperative scores were similar in both groups. The WOMAC post-operative scores (23.6 vs 20.4; p=0.037) and the KSS-Knee score (91.1 vs 87.6; p=0.027) were worse in the group of patients with self-reported allergies than in the group without allergies. The scores from the Yesavage depression questionnaire and in the SF-36 were similar in both groups.

Answer: Do patient-reported allergies cause inferior outcomes after total knee arthroplasty?

Question: Guanylin activates an intestinal guanylate cyclase (GCC) and stimulates electrolyte movement across the gut epithelium. Cells expressing guanylin messenger RNA have been localized to the epithelial cell layer of the intestine; however, the identity of the guanylin-producing cells has not been determined. The aim of this study was to identify cells that express guanylin in the rat intestine.', 'Antibodies were raised against defined proguanylin epitopes, evaluated by Western blotting, and used for immunoperoxidase histochemistry.', 'Guanylin-like immunoreactivity was localized to a subset of goblet cells. In the small intestine, most, perhaps all, goblet cells in the villi were immunopositive, as were some goblet cells in upper crypts; however, goblet cells deep within crypts were unlabeled. In the colon, goblet cells clustered in the necks and around the openings of crypts were immunopositive, whereas (as in the small intestine) goblet cells in deeper crypt regions were unlabeled. In some animals, immunoreactive columnar epithelial cells were also observed in the colon (although such cells were not apparent in the small intestine). Relative labeling of columnar cells varied from animal to animal.

Answer:
Is guanylin , an endogenous ligand for C-type guanylate cyclase , produced by goblet cells in the rat intestine?