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.
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Question: 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.

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


Question: Context: Concomitant thyroid nodules are the most common reason for false-positive ultrasonography (US) results in primary hyperparathyroidism. The aims of this prospective clinical study were to evaluate false-positive US results according to the characteristics of concomitant thyroid nodules and to determine which characteristics of thyroid nodules are important.', 'This prospective study included 120 consecutive patients with primary hyperparathyroidism. The patients were divided into 2 groups according to preoperative US results. Group 1 consisted of 32 patients with false-positive US results and group 2 consisted of 88 patients with true-positive US results.', 'The risk for false-positive US result was increased 25-fold for patients with parathyroid adenoma weight of more than 500 mg (odds ratio [OR], 25; 95% confidence interval [CI], 8.6-74.5), 75-fold for more than 1 posteriorly located thyroid (OR, 75; 95% CI, 19.3-293.4), 358-fold for the presence of exophytic thyroid nodules (OR, 358; 95% CI, 42.3-3036), and 423-fold for the presence of posteriorly located thyroid nodules (OR, 423; 95% CI, 49-3662).
Answer: Although there was no particular characteristic of concomitant thyroid nodules that contributes to false-positive US results, the posteriorly located thyroid nodules were the strongest correlate for the false-positive US results to other features.

Answer: Do the characteristics of concomitant thyroid nodules cause false-positive ultrasonography results in primary hyperparathyroidism?


Question: Context: The purpose of this study was to investigate the clinical value of real-time three-dimensional transesophageal echocardiography (RT-3D-TEE) for percutaneous transcatheter closure of multiple secundum atrial septal defects (ASDs) using a Chinese domestic occluder device.', 'From July 2008 to September 2011, 37 patients (mean age 28.4 ± 9.7 years; 24 females) with multiple secundum ASDs underwent percutaneous transcatheter closure in our institution with custom-made occluder devices. RT-3D-TEE was used to clarify the diagnosis and to help determine the operation scheme before the procedure, for real-time monitoring and guiding the operation during the procedure, and for evaluating the result shortly after the procedure.', 'The custom-made atrial septal occluders were successfully implanted in 36 patients under RT-3DTEE guidance. Twenty-seven patients were implanted with two devices and 9 patients with a single device. In two patients where the distance between the two defects was less than 7 mm (5.5 mm and 6 mm), double occluder devices were also successfully implanted. One patient underwent surgery for the complication of unstable occluder and increased residual shunt after closure. No other severe complications were observed.
Answer: RT-3D-TEE provides reliable diagnostic evidence of multiple ASDs and can help the clinician to select an appropriate operation scheme according to the number and morphology of multiple defects prior to percutaneous transcatheter closure. It also allows for proper positioning of the devices during the procedure and provides an effective means of evaluating the success of the procedure. For two devices to be implanted simultaneously in multiple ASDs, the usual requirement for the distance between the two defects may differ between our domestically made devices and the Amplatzer occluder.

Answer:
Is real-time three-dimensional transesophageal echocardiography useful for percutaneous closure of multiple secundum atrial septal defects?