instruction:
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.
question:
Context: A functional vacuolar adenosine triphosphatase (v-ATPase) complex regulates canonical Wnt/β-catenin signaling. The goal of this study was to identify the distribution of the v-ATPase in human and murine models of pancreatic intraepithelial neoplasms (PanINs) and assess its role in Wnt/β-catenin signaling.', 'We evaluated the immunolabeling pattern of the v-ATPase in human PanIN specimens and murine PanIN-1 and PanIN-2 lesions obtained from Ptf1a(Cre/+); LSL-Kras(G12D) mice. Wnt/β-catenin signaling was interrogated in primary PanIN cells by examining the phosphorylated levels of its surface coreceptor, low-density lipoprotein receptor-related protein-6 (LRP6), and its intracellular effector, nonphosphorylated β-catenin. The response of primary PanIN cells to epidermal growth factor (EGF) was assessed in the absence and presence of the v-ATPase inhibitor, concanamycin.', 'In advanced (PanIN-2), but not early (PanIN-1), lesions, the v-ATPase assumed a polarized phenotype. Blocking the v-ATPase disrupted Wnt/β-catenin signaling in primary PanIN cells despite significantly higher levels of the total and activated Wnt cell surface coreceptor, LRP6. Vacuolar adenosine triphosphatase blockade significantly decreased the total and activated levels of EGF receptor, a determinant of PanIN progression. The activation of EGF receptor and its intracellular mediator, p44/42 mitogen-activated protein kinase, was also reduced by v-ATPase blockade. This led to diminished proliferation in response to EGF ligand.
Answer: The v-ATPase regulates Wnt/β-catenin and EGF receptor signaling in PanINs.
answer:
Does polarization of the vacuolar adenosine triphosphatase delineate a transition to high-grade pancreatic intraepithelial neoplasm lesions?


question:
Context: Surfactant protein (SP) D shares target cells with the proinflammatory cytokine TNF-alpha, an important autocrine stimulator of dendritic cells and macrophages in the airways.', 'We sought to study the mechanisms by which TNF-alpha and SP-D can affect cellular components of the pulmonary innate immune system.', 'Cytokine and SP-D protein and mRNA expression was assessed by means of ELISA, Western blotting, and real-time PCR, respectively, by using in vivo models of allergic airway sensitization. Macrophage and dendritic cell phenotypes were analyzed by means of FACS analysis. Maturation of bone marrow-derived dendritic cells was investigated in vitro.', 'TNF-alpha, elicited either by allergen exposure or pulmonary overexpression, induced SP-D, IL-13, and mononuclear cell influx in the lung. Recombinant IL-13 by itself was also capable of enhancing SP-D in vivo and in vitro, and the SP-D response to allergen challenge was impaired in IL-13-deficient mice. Allergen-induced increase of SP-D in the airways coincided with resolution of TNF-alpha release and cell influx. SP-D-deficient mice had constitutively high numbers of alveolar mononuclear cells expressing TNF-alpha, MHC class II, CD86, and CD11b, characteristics of proinflammatory, myeloid dendritic cells. Recombinant SP-D significantly suppressed all of these molecules in bone marrow-derived dendritic cell cultures.
Answer: TNF-alpha can contribute to enhanced SP-D production in the lung indirectly through inducing IL-13. SP-D, on the other hand, can antagonize the proinflammatory effects of TNF-alpha on macrophages and dendritic cells, at least partly, by inhibiting production of this cytokine.
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Does surfactant protein D inhibit TNF-alpha production by macrophages and dendritic cells in mice?


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Context: Chronic rhinosinusitis (CRS) is a common inflammatory disease of the upper airways that is often categorized into subtypes including "with" and "without" nasal polyps. However, the influence of multiple important epidemiologic factors, including race, on CRS has not been investigated.', 'The present study assessed various phenotypic characteristics of CRS in patients, living in the United States, with different racial backgrounds.', 'We performed a large retrospective cohort study of patients with CRS treated at a large urban tertiary care referral center in Chicago.', 'African American (AA) patients with CRS living in Chicago were more likely to report hyposmia as a symptom of CRS. Furthermore, AA patients with CRS who failed medical therapy and required surgical intervention had a significantly higher frequency of nasal polyposis and aspirin-exacerbated respiratory disease, and a higher disease severity index on computed tomography imaging than did white patients with CRS. The increased polyposis in AAs was associated with increased hospitalization for asthma. There were no differences in the prevalence of atopy, asthma, atopic dermatitis, food allergy, duration of disease, or number of surgeries between different races.
Answer: AAs with refractory CRS are at increased risk for nasal polyposis, smell loss, aspirin-exacerbated respiratory disease, and a greater severity of disease based on imaging, resulting in increased health care utilization.
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Do african American Patients with Chronic Rhinosinusitis Have a Distinct Phenotype of Polyposis Associated with Increased Asthma Hospitalization?