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.

Q: 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.

A: Do human intestinal epithelial cells promote the differentiation of tolerogenic dendritic cells?
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Q: Context: Cigarette smoke disrupts the protective barrier established by the airway epithelium through direct damage to the epithelial cells, leading to cell death. Since the morphology of the airway epithelium of smokers does not typically demonstrate necrosis, the most likely mechanism for epithelial cell death in response to cigarette smoke is apoptosis. We hypothesized that cigarette smoke directly up-regulates expression of apoptotic genes, which could play a role in airway epithelial apoptosis.', 'Microarray analysis of airway epithelium obtained by bronchoscopy on matched cohorts of 13 phenotypically normal smokers and 9 non-smokers was used to identify specific genes modulated by smoking that were associated with apoptosis. Among the up-regulated apoptotic genes was pirin (3.1-fold, p < 0.002), an iron-binding nuclear protein and transcription cofactor. In vitro studies using human bronchial cells exposed to cigarette smoke extract (CSE) and an adenovirus vector encoding the pirin cDNA (AdPirin) were performed to test the direct effect of cigarette smoke on pirin expression and the effect of pirin expression on apoptosis.', 'Quantitative TaqMan RT-PCR confirmed a 2-fold increase in pirin expression in the airway epithelium of smokers compared to non-smokers (p < 0.02). CSE applied to primary human bronchial epithelial cell cultures demonstrated that pirin mRNA levels increase in a time-and concentration-dependent manner (p < 0.03, all conditions compared to controls). Overexpression of pirin, using the vector AdPirin, in human bronchial epithelial cells was associated with an increase in the number of apoptotic cells assessed by both TUNEL assay (5-fold, p < 0.01) and ELISA for cytoplasmic nucleosomes (19.3-fold, p < 0.01) compared to control adenovirus vector.
Answer: These observations suggest that up-regulation of pirin may represent one mechanism by which cigarette smoke induces apoptosis in the airway epithelium, an observation that has implications for the pathogenesis of cigarette smoke-induced diseases.

A: Is upregulation of pirin expression by chronic cigarette smoking associated with bronchial epithelial cell apoptosis?
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Q: Context: To investigate the effect of initial varus or valgus surgical neck alignment on outcomes of patients who sustained proximal humerus fractures treated with open reduction and internal fixation (ORIF).', 'An institutional review board approved database of proximal humerus fractures treated with locked plates was reviewed. Of 185 fractures in the database, 101 fractures were identified and met inclusion criteria. Initial varus displacement was seen in 47 fractures (OTA types 11.A2.2, A3.1, A3.3, B1.2, B2.2, C1.2, C2.2, or C2.3) and initial valgus displacement was observed in 54 fractures (OTA types 11.A2.3, B1.1, C1.1, or C2.1). All patients were treated in a similar manner and examined by the treating physician at standard intervals. Functional outcomes were quantified via the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire and physical examination data at 12 months. Radiographs were reviewed for complications of healing. Additionally, complication rate and reoperation rate were investigated.', 'Patients who presented with initial varus displacement had an average age of 59.3 years, while patients in the valgus group had an average age of 62.4 years. Overall, there was no statistically significant difference in age, sex distribution, BMI, fracture parts, screws used, or implant plate type between the two groups. At a minimum 12 months follow up, there was no significant difference in DASH scores between those presenting with varus versus valgus fracture patterns. In addition, no significant differences were seen in final shoulder range of motion in any plane. Overall, 30 patients included in this study developed a complication. A significantly greater number of patients in the initial varus cohort developed complications (40.4%), as compared to 20.3% of patients in the initial valgus cohort (P=0.03). Fourteen patients in this study underwent reoperation. Nine of these patients were in the varus cohort, while 5 were in the valgus cohort (P=0.15).
Answer: In this study, initial surgical neck displacement in varus or valgus was found to not significantly affect functional outcome. Based upon our findings, patients with varus displaced proximal humerus fractures are at a greater risk of developing postoperative complications than those who present with initial valgus displaced fracture patterns.

A:
Does initial varus displacement of proximal humerus fractures result in similar function but higher complication rates?
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