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.

Ex Input:
Context: In mice, a subpopulation of gut dendritic cells (DCs) expressing CD103 drives the development of regulatory T (T(reg)) cells. Further, it was recently described that the cross-talk between human intestinal epithelial cells (IECs) and DCs helps in maintaining gut immune homeostasis via the induction of non-inflammatory DCs. In this study, an analysis was carried out to determine whether IECs could promote the differentiation of CD103+ tolerogenic DCs, and the function of primary CD103+ DCs isolated from human mesenteric lymph nodes (MLNs) was evaluated.', "Monocyte-derived DCs (MoDCs) and circulating CD1c+ DCs were conditioned or not with supernatants from Caco-2 cells or IECs isolated from healthy donors or donors with Crohn's disease and analysed for their ability to induce T(reg) cell differentiation. In some cases, transforming growth factor beta (TGFbeta), retinoic acid (RA) or thymic stromal lymphopoietin (TSLP) were neutralised before conditioning. CD103+ and CD103- DCs were sorted by fluorescence-activated cell sorting (FACS) from MLNs and used in T(reg) cell differentiation experiments.", "It was found that human IECs promoted the differentiation of tolerogenic DCs able to drive the development of adaptive Foxp3+ T(reg) cells. This control was lost in patients with Crohn's disease and paralleled a reduced expression of tolerogenic factors by primary IECs. MoDCs differentiated with RA or IEC supernatant upregulated the expression of CD103. Consistently, human primary CD103+ DCs isolated from MLNs were endowed with the ability to drive T(reg) cell differentiation. This subset of DCs expressed CCR7 and probably represents a lamina propria-derived migratory population.
Answer: A population of tolerogenic CD103+ DCs was identified in the human gut that probably differentiate in response to IEC-derived factors and drive T(reg) cell development.

Ex Output:
Do human intestinal epithelial cells promote the differentiation of tolerogenic dendritic cells?


Ex Input:
Context: To assess the role of whole-body computed tomography (CT) for determining morphological suitability before multiorgan retrieval (MOR) in brain dead patients.', 'Fifty-one clinically brain dead patients (21 women, 30 men; mean age 61 year±15) were included in this prospective, single center study. All patients had CT angiography of the brain and whole-body CT examination. CT images were evaluated for the presence of morphological abnormalities of lungs, liver and other abdominal organs and presence of vascular anatomical variants. The results of CT examinations were compared to intraoperative findings observed during organ harvesting and/or the results of histopathological analysis of biopsy specimens. The impact of whole-body CT examination on the harvesting process was evaluated.', 'Ninety-five percent of vascular anatomical variants that were found intraoperatively were depicted on CT. CT density measurements predicted surgical finding of steatosis in 80% of patients. Whole-body CT changed the MOR strategy in 21/51 patients (41%) including 3 MOR cancellations and 8 grafts refusals, whereas organ harvesting was continued in 10 patients after histopathological analysis was performed.
Answer: Selection of potential graft donors using whole-body CT is reliable and improves graft selection during MOR.

Ex Output:
Is simultaneous CT angiography and whole-body CT an effective imaging approach before multiorgan retrieval?


Ex Input:
Context: The microbial etiology of periradicular lesions is recognized; however, the bacterial profile of these lesions is not well elucidated. The purpose of this study was to determine the frequency of bacterial colonization in these lesions and to characterize the bacterial community present in root ends and periradicular lesions.', 'Thirty-four adult patients who presented for apicoectomy of persistent periradicular lesions after endodontic therapy were selected for the study and samples of periradicular tissue and resected root ends collected. Total bacterial levels were estimated for 34 paired periradicular lesions and root ends using real-time polymerase chain reaction with universal bacterial primers. Sixteen pairs of these samples were analyzed using ribosomal 16S cloning and sequencing for bacterial identification.', 'Bacteria were detected more consistently and at higher levels in root ends. Periradicular lesions exhibited a diverse microbial profile with many uncultivated phylotypes. Enterococcus faecalis and Burkholderia cepacia predominated in both samples. Campylobacter gracilis and Streptococcus gordonii were associated with root ends, whereas Atopobium rimae, Peptostreptococcus micros, Streptococcus genomospecies C8, Dialister sp E2_20 E1, and Eubacterium strain A35MT were associated with periradicular lesions.
Answer: Persistent periradicular lesions are polymicrobial infections with many as-yet-uncultivated and unknown bacterial species. The bacterial load and microbial profile of root ends is significantly different from the soft-tissue lesion, indicating the presence of diverse bacterial populations in these tissues.

Ex Output:

Does molecular analysis of persistent periradicular lesions and root end reveals a diverse microbial profile?