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.

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.
Does surfactant protein D inhibit TNF-alpha production by macrophages and dendritic cells in mice?

Context: To chemically identify and quantify glucose degradation products in heat sterilized fluids for peritoneal dialysis.', 'Three different brands of commercial PD-fluids and one laboratory made fluid, sterilized either by heat or filtration, were investigated for the presence of aldehydes.', 'Aldehydes were identified and quantified using high performance liquid chromatography and gas chromatography.', 'The tested brands of heat sterilized PD-fluids were found to contain several different aldehydes while the sterile filtered PD-fluid contained none. The highest concentrations in commercial PD-fluids of these aldehydes were: acetaldehyde (420 microns), glyoxal (14 microns), methylglyoxal (12 microns) and formaldehyde (11 microns). Valeraldehyde was also identified but not quantified. The presence of 5-HMF (15 microns) and 2-furaldehyde (2 microns), which has been identified by others, was confirmed.
Answer: The heat sterilization of commercial PD-fluids gives rise to several aldehydes which may contribute to adverse effects of PD-fluids on patients.
Does heat sterilization of fluids for peritoneal dialysis give rise to aldehydes?

Context: The aim of this study was to investigate copeptin levels in serum, and assess their associations with type 2 diabetes (T2DM) and diabetic complications.', 'In this post hoc analysis, serum levels of copeptin were tested in 306 patients with T2DM. Clinical information including diabetic retinopathy (DR) and diabetic nephropathy (DN) were collected. The relation of serum copeptin with DR and DN were investigated with the use of logistic regression models according to equal quartiles of the distributions of serum copeptin.', 'We found that serum copeptin levels were significantly higher in diabetes as compared to normal controls [9.4(IQR, 7.4-12.5) pmol/L vs. 4.1(IQR, 2.5-6.2) pmol/L; P<0.0001]. In multivariate analysis, there was an increased risk of T2DM associated with copeptin levels (OR 1.312, 95% CI: 1.204-1.403; P<0.0001) after adjusting for possible confounders. After adjustment for possible confounders, serum copeptin levels were positively associated with the DR (odds ratio [OR], 1.117; 95% confidence interval [CI], 1.072-1.241; P<0.001) and DN (OR, 1.259; 95% CI, 1.198-1.323; P<0.001). Compared with the first quartile of serum copeptin levels, the ORs for DR and DN were as follows: second quartile, 1.19 (95% CI, 0.94-1.51, P=0.12) and 1.37 (95% CI, 0.78-2.37, P=0.28); third quartile, 1.61 (95% CI, 1.18-2.43, P=0.005) and 2.12 (95% CI, 1.32-3.27, P=0.003); fourth quartile, 2.83 (95% CI, 2.04-4.93; P<0.001) and 3.48 (95% CI, 1.77-7.03; P<0.001), respectively.
Answer: Using a post-hoc analysis our data show that elevated serum levels of copeptin are associated with type 2 diabetes and diabetic complications in Chinese population, suggesting a potential role of the AVP system (copeptin) in the pathophysiology of diabetes.
Are serum levels of copeptin associated with type 2 diabetes and diabetic complications in Chinese population?