TASK DEFINITION: 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.
PROBLEM: Context: To investigate the existence condition of hepatitis B surface antigen(HBsAg) termination codon bias.', 'A total of 174 reference sequences of all kinds of Hepatitis B virus(HBV) genotypes were chosen from GenBank, and compared by BioEdit. Then secondary structure of RNA was constructed and analyzed together.', '(1) There were two types of HBsAg termination codon: TAA and TGA in 174 reference sequences. TAA was in 124 cases (71.26%); and TGA in 50 cases (28.74%). (2) There was codon bias selection in HBsAg termination codon, and it could affect the secondary structure of RNA and amino acid sequence encoding protein.\Question: Does [ Hepatitis B surface antigen terminate codon bias selection ]?

SOLUTION: HBsAg termination codon bias exists and may be related to RNA structure and the conservation of protein function in the evolutionary progress.

PROBLEM: Context: Triptolide (TPT), a component of the Chinese herb Triptergium wilfordii, has potent immunosuppressive and anti-inflammatory activity and is used clinically in recipients of kidney transplantation.', 'This work aimed to investigate the effect of TPT on the differentiation of regulatory T lymphocytes (Tregs) from CD4+ cells in rats.', 'MACS-purified rat CD4+ cells were costimulated with anti-CD3 and anti-CD28 in the presence of TGF-beta to induce the expression of FoxP3, which was detected by flow cytometry. TPT and cyclosporine A (CsA) were separately added into the cultures to observe the effect on the expression of FoxP3. Kidney transplantation was performed in rats that either received no treatment or were treated with TPT after transplantation.', 'TPT treatment enhanced the expression of FoxP3 in CD4+ cells, whereas CsA inhibited the FoxP3 expression. In the rat kidney transplantation model, the recipient rats treated with TPT survived longer than the control rats (18-19.83 vs 6.83 days, P<0.05). Meanwhile, the FoxP3+ T cells in the spleens of treated rats were higher than those from the untreated rats (12.4% vs 4.7%, P<0.05).\Question: Does triptolide promote generation of FoxP3+ T regulatory cells in rats?

SOLUTION: These data suggest that TPT may promote the differentiation of CD4+ cells to FoxP3+ Tregs. This would be at least one of the pathways responsible for the immunosuppressive activity of TPT.

PROBLEM: Context: Reabsorption of bile acids from the intestine by ileal bile acid transporter is pivotal for the enterohepatic circulation of BAs and sterol homoeostasis.', 'To assess tolerability and study, bile acid metabolism in a phase 1 trial with the selective ileal bile acid transporter inhibitor A4250.', 'A randomised double-blind, single-ascending dose (SAD) and multiple-ascending-dose study consisting of five cohorts comprising 40 individuals with a single administration of A4250 (0.1, 0.3, 1, 3, or 10\xa0mg) or placebo and three cohorts comprising 24 individuals with a 1-week administration of A4250 (1 or 3\xa0mg once daily or 1.5\xa0mg twice daily) or placebo. For the multiple-ascending-dose study, bile acids were measured by HPLC-MS in plasma and faeces, and fibroblast growth factor 19 (FGF19) and 7α-hydroxy-4-cholesten-3-one (C4) were measured in plasma.', 'No serious adverse events occurred and all participants finished the trial per protocol. At the end of the multiple-ascending-dose study, plasma total bile acids and FGF19 decreased by 47% and 76%, respectively, at 3\xa0mg/day (P\xa0<\xa00.01), and by 15% and 16%, respectively, at 1.5\xa0mg twice daily (P\xa0<\xa00.05). Plasma C4 and faecal bile acids increased at all dose regimens, by 555%, 664%, 292% and 338%, 421%, 420%, respectively (P\xa0<\xa00.01-0.05). The primary bile acids cholic and chenodeoxycholic acids constituted the majority of faecal bile acids in the A4250-treated groups.\Question: Does the ileal bile acid transporter inhibitor A4250 decrease serum bile acids by interrupting the enterohepatic circulation?

SOLUTION:
A4250 is well tolerated. By blocking ileal bile acid transporter in the terminal ileum, it highly efficiently interrupts the enterohepatic circulation of BAs, and should be of benefit to patients with cholestatic liver diseases. Clinical Trial registration EudraCT 2013-001175-21.