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.

Q: Context: Small studies suggest exogenous estrogen may improve vitamin D status, but the etiology is unclear because women who use hormones may make lifestyle choices that differentially affect vitamin D status.', 'Our objective was to investigate the association between use of hormonal contraception and 25-hydroxy-vitamin D (25(OH)D).', 'We used linear regression modeling of cross-sectional data to estimate percent change in season-adjusted serum 25(OH)D with estrogen use after adjustment for other factors.', 'At the enrollment clinic visit (2010-2012) into a cohort study of uterine fibroids, each subject provided a blood sample, had anthropomorphic variables and skin reflectance measured, and answered questionnaires on demographics, dietary and supplement intake, contraceptive use, reproductive and medical history, and behaviors.', 'A total of 1662 African American women, community volunteers, 23-34 years old, living in the Detroit, Michigan, area were included.', 'None.', 'Serum 25(OH)D was measured.', 'Serum 25(OH)D concentrations were low (70% <20 ng/ml). Current use of an estrogen-containing contraceptive was associated with a 20% (95% confidence interval: 14-27) increase in 25(OH)D after adjustment. There was no increase in 25(OH)D among participants who had used estrogen in the past, but were not current users, indicating that results were unlikely to be due to unmeasured confounding by factors related to contraceptive choice.
Answer: The increase in 25(OH)D with use of estrogen-containing contraceptives raise mechanistic questions regarding the biological pathways involved, and highlights the need for studies that examine possible endogenous estrogen effects on vitamin D.

A: Does use of Estrogen-Containing Contraception be Associated With Increased Concentrations of 25-Hydroxy Vitamin D?
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Q: Context: To study the effect of removal of YY1 binding sites within the LCR region of HPV 16 on viral transforming activity.', 'Previously we had generated new plasmids carrying HPV 16 whole genome, which contained naturally occurred mutated LCR sequences. The viral transforming abilities on mouse fibroblasts were evaluated in anchorage-independent assays, while the expression and activity of YY1 protein in fibroblasts were tested with EMSA and luciferase assays.', 'YY1 protein was expressed in mouse fibroblasts C127, with ability for DNA binding and repression on P97 activity. Both HPV 16 wild-type DNA and mutated DNAs were transfected into C127 cells and spread to the soft-agarose mediums after selecting with G 418. The growth numbers of the cells transfected with mutated HPV 16 DNAs were 2-10 fold more than that with wild-type HPV 16 DNA.
Answer: Like in epithelial cells or cell lines, transcription regulator YY1 is widely expressed in rodent fibroblasts. Removal of YY1 binding motifs can elevate in the context of the whole genome, the anchorage independent growth ability and the transforming capacity of HPV 16 on the mouse fibroblasts.

A: Does [ Removal of YY1 binding sites in HPV 16 LCR increase viral transforming activities on mouse fibroblasts ]?
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Q: Context: MiR-378 has been reported to be related to cell survival, tumor growth and angiogenesis and may participate in hepatocellular carcinoma (HCC) development and prognosis. Genetic variants in primary miR-378 (pri-miR-378) may impact miR-378 expression and contribute to HCC risk and survival. This study aimed to assess the associations between a genetic variant in primary miR-378 and HCC susceptibility and prognosis.', 'We conducted a case-control study to analyze the association of rs1076064 in pri-miR-378 with hepatocellular carcinoma risk in 1300 HCC patients with positive hepatitis B virus (HBV) and 1344 HBV carriers. Then, we evaluated the correlation between the polymorphism and hepatocellular carcinoma prognosis in 331 HCC patients at either intermediate or advanced stage without surgical treatment.', 'The variant genotypes of rs1076064 were associated with a decreased HCC risk in HBV carriers [Adjusted odds ratio (OR)\u200a=\u200a0.90, 95% confidence intervals (CI)\u200a=\u200a0.81-1.00, P\u200a=\u200a0.047]. Moreover, HCC patients with the variant genotypes were associated with a better survival [Adjusted hazard ratio (HR)\u200a=\u200a0.70, 95% CIs\u200a=\u200a0.59-0.83, P<0.0001 in an additive genetic model]. The reporter gene assay showed that the variant G allele of rs1076064 exerted higher promoter activity than the A allele.
Answer: These findings indicate that rs1076064 may be a biomarker for HCC susceptibility and prognosis through altering pri-miR-378 transcription.

A:
Is a genetic variant in primary miR-378 associated with risk and prognosis of hepatocellular carcinoma in a Chinese population?
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