In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.

Q: Context: Plasma high-density lipoprotein (HDL) level is inversely correlated with the risk of atherosclerosis. However, the cellular mechanism by which HDL exerts antiatherogenic actions is not well understood. In this study, we focus on the lipid components of HDL as mediators of the lipoprotein-induced antiatherogenic actions.', 'HDL and sphingosine 1-phosphate (S1P) stimulated the migration and survival of human umbilical vein endothelial cells. These responses to HDL and S1P were almost completely inhibited by pertussis toxin and other specific inhibitors for intracellular signaling pathways, although the inhibition profiles of migration and survival were different. The HDL-stimulated migration and survival of the cells were markedly inhibited by antisense oligonucleotides against the S1P receptors EDG-1/S1P1 and EDG-3/S1P3. Cell migration was sensitive to both receptors, but cell survival was exclusively sensitive to S1P1. The S1P-rich fraction and chromatographically purified S1P from HDL stimulated cell migration, but the rest of the fraction did not, as was the case of the cell survival.\Question: Does high-density lipoprotein stimulate endothelial cell migration and survival through sphingosine 1-phosphate and its receptors?

A: HDL-induced endothelial cell migration and survival may be mediated by the lipoprotein component S1P and the lipid receptors S1P1 and S1P3.
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Q: Context: Allergic rhinitis (AR) is a complex chronic inflammatory disease of the nasal mucosa, caused by an interaction between genetic and environmental factors. As evidence suggests that some genetic variants may increase susceptibility to both AR and asthma, the objective of this study was to identify asthma susceptibility variants associated with AR in the Chinese population.', 'A cohort of 402 individuals with physician-diagnosed AR and 416 healthy controls were recruited from the Han Chinese population in Beijing. DNA was extracted from the peripheral blood and a total of 12 single-nucleotide polymorphisms (SNPs) shown to be associated with asthma in Japanese subjects were selected for genotyping using the SequenomMassARRAY technology platform.', 'Analysis of frequency differences of allele between the AR patients and control subjects showed that the C allele of rs204993 in the pre-B-cell leukemia homeobox 2 (PBX2) gene from the 6p21.3 locus was significantly associated with AR (p = 0.0006, pcorrected = 0.0340). Genotype analysis further confirmed the difference in distribution of this variant between AR patients and controls in the both the dominant (pT/C+C/C vs T/T = 7.37×10(-5) ) and co-dominant (pT/C vs T/T = 1.98 × 10(-4) , pC/C vs T/T = 0.004) models.\Question: Does variant of PBX2 gene in the 6p21.3 asthma susceptibility locus is associate with allergic rhinitis in Chinese subjects?

A: These results suggest that the PBX2 gene in the 6p21.3 asthma susceptibility locus may be associated with increased risk for both AR and asthma in Chinese subjects.
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Q: Context: MicroRNAs (miRNAs) play important roles in chondrogenic differentiation of mesenchymal stem cells (MSCs). However, the regulation of miR-30a during such process has not yet been well understood. The aim of the study was to investigate the effects of miR-30a on chondrogenic differentiation of MSCs and explore the underlying mechanisms.', 'MSCs were isolated from rat bone marrow, and their immunophenotypes and multilineage differentiation potentials were identified. MiR-30a mimics or inhibitor were transfected into rat MSCs and SW1353 cells, respectively, and then the effects of miR-30a on chondrogenic differentiation were detected. The predicted target gene Delta-like 4 (DLL4, a ligand of the Notch signaling family) was verified by luciferase reporter assay, quantitative real time PCR and western blot.', "MiR-30a was significantly up-regulated during chondrogenic differentiation of rat MSCs. Additionally, transfection of miR-30a mimics remarkably promoted the differentiation of rat MSCs into chondrocytes as evidence by the notably increased mRNA and protein expression levels of chondrogenic markers Collagen II and aggrecan as well as the enhanced alcian blue staining intensity, whereas inhibition of miR-30a obviously suppressed such process. Furthermore, during chondrogenesis, DLL4 expression was found to significantly decrease at both mRNA and protein levels, which was negatively regulated by miR-30a through directly targeting the 3'UTR of DLL4.\Question: Does microRNA-30a promote chondrogenic differentiation of mesenchymal stem cells through inhibiting Delta-like 4 expression?

A:
Our results indicate that miR-30a acts as a key promoter for chondrogenic differentiation of MSCs by down-regulating DLL4 expression, and provide a novel insight on miRNA-mediated MSC therapy for cartilage-related disorders including osteoarthritis.
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