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 Input:
Context: Scutellaria barbata D.Don has been applied to treat cancers, inflammation and urinary disease. However, its antitumor mechanism still remains unclear.', 'With methylene chloride fraction of Herba Scutellariae barbatae (MCSB), apoptosis-related experiments were carried out on human U937 leukemia cells by (a) 2,3-bis[2-4-nitro-5-sulphophenyl]2H-tetrazolium-5-carboxanilide (XTT) assay for cytotoxicity; (b) terminal deoxynucleotidyl-transferase-mediated dUTP nick end labeling (TUNEL) assay for morphological changes; (c) cell cycle analysis; (d) Western blot analysis of poly(ADP-ribose) polymerase (PARP), caspase-8, caspase-9, caspase-3 and Bax, Bcl-2 and cytochrome c expressions for apoptosis signaling pathway.', 'MCSB inhibited the proliferation of human U937 leukemia cells in a dose-dependent manner (IC50 = approximately 10 microg/ml). MCSB dose-dependently increased the sub-G1 DNA contents by cell cycle analysis. DNA fragments indicating induction of apoptosis were observed in MCSB-treated U937 cells by TUNEL assay. Caspase-9 and caspase-3 were activated while caspase-8 was intact by MCSB. Similarly, MCSB effectively cleaved PARP, increased the ratio of Bax/Bcl-2 and released the cytochrome c from mitochondria during apoptosis in U937 cells.
Answer: Our results suggest that MCSB can induce apoptosis via the mitochondria-mediated signaling pathway.

Ex Output:
Does methylene chloride fraction of Scutellaria barbata induce apoptosis in human U937 leukemia cells via the mitochondrial signaling pathway?

Ex Input:
Context: To evaluate the impact of elevated serum 4A levels on the hormonal and metabolic features of the different phenotypes of PCOS.', '1276 women with PCOS according to the Rotterdam criteria were included, in whom serum hormonal levels were determined.', 'In PCOS women as a whole, as well as in patients presenting clinical and/or biochemical hyperandrogenemia (phenotypes I and II), 4A levels >3.8 ng/ml were positively related to LH, LH/FSH ratio, T, DHEAS, 17 OH progesterone and FAI and negatively related to T/4A ratio. In the milder phenotype III, a positive correlation between 4A levels >3.8 ng/ml and T, DHEAS, 17 OH progesterone and FAI and a negative one between increased 4A and T/4A ratio were reported. In the whole PCOS group with androstenedione >3.8 ng/ml, an increased ovarian volume was observed, while a greater mean follicular number was found only in phenotypes I and II.
Answer: Increased serum 4A levels, which are associated with more severe PCOS phenotypes, possibly contribute to the worsening of PCOS features and therefore could be a valuable marker of biochemical hyperandrogenemia.

Ex Output:
Is elevated serum androstenedione associated with a more severe phenotype in women with polycystic ovary syndrome ( PCOS )?

Ex Input:
Context: The purpose of this study was to explore an applicable approach for prolonging the survival of heterogenetic skin grafts on burn wounds with CTLA4Ig.', 'An adenovirus vector named Ad-CTLA4Ig, which could express human CTLA4Ig fusion protein, was constructed. Infecting and replicating in 293 cells, more Ad-CTLA4Ig and recombinant human CTLA4Ig (rhCTLA4Ig) were prepared, respectively. In a rat flame thermal injury model, the effect of rhCTLA4Ig on survival time of human skin graft on the eschar-excised rat burn wound was observed. Meanwhile, the efficiency of Ad-CTLA4Ig infecting cultured skin fibroblasts, keratinocytes, and partial-thickness skin samples were checked by CTLA4Ig expression essay. Then, the Ad-CTLA4Ig was administered locally on the eschar-excised wound and dermis of the skin graft, and the survival time of the human skin graft on burn wound was measured. The influence of the systemic immune function by rhCTLA4Ig and Ad-CTLA4Ig were also determined.', 'The prepared rhCTLA4Ig from the supernatant of Ad-CTLA4Ig-infected 293 cells was verified by sodium dodecyl sulfate polyacrylamide gel electrophoresis sodium dodecyl sulfate poly-acrylamide gel electrophoresis and Western blot. It was found that CTLA4Ig could significantly prolong the xenogeneic skin graft survival in a dosage-dependent manner. Interestingly, the survival time was longer when CTLA4Ig was used 24 hours posttransplantation than that at hour 0. The expression of CTLA4Ig could be observed in the cultured skin fibroblasts, keratinocytes, and skin pieces soon after Ad-CTLA4Ig transfection, as demonstrated by either immunocellular chemistry or immunohistochemistry assay. When Ad-CTLA4Ig was locally administered during skin transplantation on burn wound, the survival time was increased from 7.9 days of control group to 21.6 days, whereas the systemic immune function was not affected.
Answer: Administration of Ad-CTLA4Ig locally could prolong the survival time of xenogeneic skin graft on burn wound without significantly influencing the systemic immune function.

Ex Output:
Do cTLA4Ig introduced by adenovirus vector locally to prolong the survival of xenogeneic skin grafts on rat burn wounds?