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 Q]: Context: Women with antiphospholipid syndrome (APS) are at increased risk of recurrent pregnancy loss (RPL) and preeclampsia. Antiphospholipid antibodies (aPL) directly alter trophoblast function. Treatment with low molecular weight heparin (LMWH) reduces the risk of RPL but not preeclampsia. Moreover, LMWH stimulates trophoblast sFlt-1 release, an anti-angiogenic factor associated with preeclampsia. Since vitamin D deficiency is associated with APS and preeclampsia, this study sought to determine the effect of vitamin D on trophoblast function in the setting of aPL and LMWH.', 'A human first trimester trophoblast cell line (HTR8) and primary trophoblast cultures were treated with or without aPL in the presence and absence of vitamin D, LMWH or both. Trophoblast secretion of inflammatory cytokines and angiogenic factors were measured by ELISA.', 'Vitamin D alone or in combination with LMWH attenuated the aPL-induced trophoblast inflammatory response in the HTR8 cells and primary cultures. While vitamin D did not have any impact on aPL-mediated modulation of angiogenic factors in the primary trophoblast, it significantly inhibited LMWH-induced sFlt-1 release.
Answer: LMWH in combination with vitamin D may be more beneficial than single-agent therapy by preventing aPL-induced trophoblast inflammation and reversing LMWH-induced sFlt-1 secretion.
[EX A]: Does vitamin D reverse aPL-induced inflammation and LMWH-induced sFlt-1 release by human trophoblast?

[EX Q]: Context: The tumor necrosis factor (TNF) gene is located within the highly polymorphic major histocompatibility complex region, exhibiting the -308 GA promoter region polymorphism and six microsatellites (TNFa-f) spanning the region nearby the TNF locus.', 'In the present study, we evaluated the frequency of -308 GA and TNFa-e polymorphisms and respective haplotypes (in chromosomal sequence: TNFd-TNFe-308GA-TNFc-TNFa-TNFb), in 222 patients with AIDS, 52 of whom exhibited cytomegalovirus retinitis, and in 202 healthy HIV-negative individuals.', 'TNF microsatellite and single nucleotide polymorphism typings were performed by PCR followed by polyacrylamide gel electrophoresis.', 'The TNF-308A allele and the 4-3-G-2-7-1 haplotype were associated with susceptibility to AIDS, whereas the TNFb4 allele and the 3-3-G-1-11-4 haplotype were associated with protection against AIDS development. The TNFc2 allele and the 4-1-G-2-2-1 haplotype, which contains the TNFc2 allele, were associated with cytomegalovirus retinitis.
Answer: This study highlights that polymorphic sites spanning the region nearby the TNF locus are associated with AIDS per se and with cytomegalovirus retinitis in AIDS patients.
[EX A]: Are tumor necrosis factor region polymorphisms associated with AIDS and with cytomegalovirus retinitis?

[EX Q]: Context: Vascular calcification can predict cardiovascular (CV) morbidity and mortality in patients with end-stage renal disease. We evaluated the prevalence, association factors, and outcomes of chest X-ray-detected aortic arch calcification (AoAC) in patients undergoing peritoneal dialysis (PD).', 'We included 190 patients undergoing PD (mean age, 52.614.3years) for whom chest radiographs were available. AoAC revealed by chest X-ray was graded from 0 to 3 according to an AoAC score (AoACS). Multiple regression analyses were used to determine the factors associated with AoACS. After adjusting for age, sex, PD duration, diabetes mellitus, mean blood pressure, and history of CV disease, the association between AoAC grading and mortality were assessed using the Kaplan-Meier curve and Cox proportional hazard model.', 'Age (p<0.001), PD duration (p=0.004), history of CV disease (p<0.001), and renal Kt/V (p=0.031) were associated with AoACS. After a mean follow-up of 55.132.1months, patients with Grade 2 (p=0.011) or Grade 3 (p<0.001) AoAC had higher all-cause mortality than patients with Grade 0 AoAC. In addition, patients with Grades 2 and 3 AoAC had higher CV-related mortality than those with Grades 0 and 1 AoAC (p=0.013). Grade 2 [hazard ratio (HR)=2.736; 95% confidence interval (CI), 1.038-7.211; p=0.042] and Grade 3 AoAC (HR=3.289; 95% CI, 1.156-9.359; p=0.026) remained associated with all-cause mortality after adjustment. Similarly, Grades 2 and 3 AoAC (HR=36.05; 95% CI, 3.494-372; p=0.026) significantly correlated with CV mortality after adjustment.
Answer: In patients undergoing PD, CXR-detected severe AoAC was an independent risk factor for all-cause and CV mortalities.
[EX A]:
Does severe aortic arch calcification predict mortality in patients undergoing peritoneal dialysis?