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.

Example Input: Context: Women diagnosed with pregnancy-associated breast cancer postpartum have a worse prognosis, stage for stage, than other women with breast cancer. The time of breast involution is tumor promotional. The extracellular matrix protein tenascin-C is upregulated during involution in animal models and promotes breast cancer progression. It interacts with transforming growth factor (TGF), which also is involved in breast involution and breast cancer progression. Little is known about the expression of tenascin-C during human breast involution, nor its relationship to TGF. The purpose of this study was to investigate the expression of tenascin-C throughout lactation, as well as its relationship to TGF1 and TGF2.', 'Three milk samples from 25 lactating women (transitional, whole, and wean) were collected, separated into components (cells, fat, and skim), and the skim fraction analyzed for total protein, tenascin-C, TGF1, and TGF2. Tenascin-C, TGF1, and TGF2 were detectable in all milk samples.', 'Highest tenascin-C levels on average were found in whole milk, whereas highest mean TGF1 and TGF2 levels were in wean milk. Wean samples on average had higher levels of both TGF1 (26%) and TGF2 (>500%) than matched transitional milk samples. Tenascin-C levels in wean milk were associated with nursing length (p = 0.048). Combining all three milk collection time points, tenascin-C exhibited a weak inverse correlation with TGF1 and TGF2 (p < 0.1). The inverse correlation at the wean time point was stronger for TGF2 than -1 (-0.37 versus -0.25). Tenascin-C, a protein known to promote breast cancer progression, is expressed throughout lactation.
Answer: The inverse correlation with TGF2 in wean milk suggests a possible interaction during breast involution, which should be further investigated.
Example Output: Does expression of the Extracellular Matrix Protein Tenascin-C vary During Lactation?

Example Input: Context: The goals of this study were to evaluate the complication rate for intraoperative placement of a long-term central venous catheter (CVC) using intraoperative ultrasound (US) and fluoroscopy and to examine the feasibility for eliminating routine postprocedure chest X-ray.', 'Retrospective data pertaining to operative insertion of long-term CVC were collected and the rate of procedural complications was determined.', 'From January 2008 to August 2013, 351 CVCs were placed via the internal jugular vein using US. Of these, 93% had a single, successful internal jugular vein insertion. The complications included 4 arterial sticks (1.14%). Starting in October 2012, postprocedure chest radiography (CXR) was eliminated in 170 cases, with no complications. A total of $29,750 in charges were deferred by CXR elimination.
Answer: This review supports the use of US for CVC placement with fluoroscopy in reducing the rate of procedural complications. Additionally, with fluoroscopic imaging, postprocedural CXR can be eliminated with associated healthcare savings.
Example Output: Does image-guided placement of long-term central venous catheters reduce complications and cost?

Example Input: Context: Transcription in Escherichia coli generates positive supercoiling in the DNA, which is relieved by the enzymatic activity of gyrase. Recently published experimental evidence suggests that transcription initiation and elongation are inhibited by the buildup of positive supercoiling. It has therefore been proposed that intermittent binding of gyrase plays a role in transcriptional bursting. Considering that transcription is one of the most fundamental cellular processes, it is desirable to be able to account for the buildup and release of positive supercoiling in models of transcription.', "Here we present a detailed biophysical model of gene expression that incorporates the effects of supercoiling due to transcription. By directly linking the amount of positive supercoiling to the rate of transcription, the model predicts that highly transcribed genes' mRNA distributions should substantially deviate from Poisson distributions, with enhanced density at low mRNA copy numbers. Additionally, the model predicts a high degree of correlation between expression levels of genes inside the same supercoiling domain.
Answer: Our model, incorporating the supercoiling state of the gene, makes specific predictions that differ from previous models of gene expression. Genes in the same supercoiling domain influence the expression level of neighboring genes. Such structurally dependent regulation predicts correlations between genes in the same supercoiling domain. The topology of the chromosome therefore creates a higher level of gene regulation, which has broad implications for understanding the evolution and organization of bacterial genomes.
Example Output:
Does a biophysical model of supercoiling dependent transcription predict a structural aspect to gene regulation?