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.

[EX Q]: Context: Nonviral vectors based on polyethylenimine (PEI) usually contain an excess of PEI that is not complexed to DNA. Since unbound PEI contributes to cellular and systemic toxicity, purification of polyplexes from unbound PEI is desirable.', 'Size exclusion chromatography (SEC) was used to purify PEI polyplexes of free PEI. Transfection properties of purified polyplexes and the effect of free PEI on gene delivery were studied in vitro and in vivo after systemic application into mice.', 'SEC did not change the size and zeta-potential of polyplexes. Independent of the amount of PEI used for complex formation, purified PEI polyplexes had the same final PEI nitrogen/DNA phosphate ratio of 2.5. Notably, purified PEI polyplexes demonstrated low cellular and systemic toxicity. High transfection efficiency was achieved with purified polyplexes at high DNA concentrations (8-15 microg/ml). At low DNA concentrations (2-4 microg/ml) gene transfer with purified particles was less efficient than with polyplexes containing free PEI both in vitro and in vivo. Mechanistic studies showed that free PEI partly blocked cellular association of DNA complexes but was essential for the following intracellular gene delivery. Adding free PEI to cells treated with purified particles with a delay of up to 4 h resulted in significantly enhanced transfection efficiency compared with non-purified particles or purified particles without free PEI.\Question: Does purification of polyethylenimine polyplexes highlight the role of free polycations in gene transfer?
[EX A]: This study presents an efficient method to remove free PEI from PEI polyplexes by SEC. Our results from transfection experiments demonstrate that free PEI substantially contributes to efficient gene expression but also mediates toxic effects in a dose-dependent manner. Purified polyplexes without free PEI have to be applied at increased concentrations to achieve high transfection levels, but exhibit a greatly improved toxicity profile.

[EX Q]: Context: Recent studies have demonstrated that mouthwash made with the traditional Japanese medicine hangeshashinto exhibits anti-inflammatory action and alleviates oral mucositis scores, including pain complaints, in patients undergoing chemoradiotherapy. However, no study has demonstrated the mechanism underlying how hangeshashinto provides pain relief in oral ulcers.', 'The analgesic effects on pain-related behaviors following the topical application of hangeshashinto were evaluated in an oral ulcer rat model treated with acetic acid using recently developed methods. Indomethacin, the representative anti-inflammatory agent, was intraperitoneally administered. The tissue permeability of the oral mucosa was histologically evaluated after applying the fluorescent substance FluoroGold.', 'The topical application of hangeshashinto in ulcerative oral mucosa suppressed mechanical pain hypersensitivity over 60 min, without any effects on healthy mucosa. The same drug application also inhibited oral ulcer-induced spontaneous pain. Indomethacin administration failed to block the mechanical pain hypersensitivity, though it did largely block spontaneous pain. Topical anesthesia with lidocaine showed hyposensitivity to mechanical stimulation in healthy mucosa. In the ulcer regions in which the oral epithelial barrier was destroyed, deep parenchyma was stained with FluoroGold, in contrast to healthy oral mucosa, in which staining was limiting to the superficial site.\Question: Does the traditional Japanese medicine hangeshashinto alleviate oral ulcer-induced pain in a rat model?
[EX A]: Hangeshashinto leads to long-lasting analgesic effects, specifically in the ulcer region by destroying the epithelial barrier. Hangeshashinto alleviates oral ulcer-induced pain in inflammation-dependent and/or independent manner.

[EX Q]: Context: Activation of NF-kappaB signaling pathway plays a critical role in the initiation and progression of carcinogenesis. However, the role of NF-kappaB pathway in esophageal squamous cell carcinoma (ESCC) has not been fully elucidated. Studies have shown that curcumin possesses anti-infection and anti-oxidation effects. This study was to evaluate whether curcumin could induce apoptosis through inhibition of NF-kappaB signaling pathway in ESCC cells.', 'Expressions of pIkappaBalpha and Bcl-2 were detected using Western blott after incubation of ESCC cells with curcumin (50 micromol/L) at different time points. Apoptosis and the number of viable ESCC cells were analyzed using flow cytometry and MTT, respectively, after the treatment of curcumin, 5-FU, or the combination of curcumin and 5-FU.', 'In two ESCC cell lines, EC9706 and Eca109,curcumin inhibited IkappaBalpha phosphorylation and Bcl-2 in a time-dependent manner; curcumin alone increased cell apoptosis (P<0.05), and the effect became more prominent when it was combined with 5-FU (P<0.05); curcumin plus 5-FU exerted a stronger inhibition effect on cell proliferation than curcumin alone (P<0.05) or 5-FU alone (P<0.05).\Question: Does [ Curcumin promote apoptosis of esophageal squamous carcinoma cell lines through inhibition of NF-kappaB signaling pathway ]?
[EX A]:
Curcumin inhibits the phosphorylation of IkappaBalpha, leading to suppression of proliferation, induction of apoptosis and an increase of the sensitivity of ESCC cell lines towards 5-FU.