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: Current views on the control of cell development are anchored on the notion that phenotypes are defined by networks of transcriptional activity. The large amounts of information brought about by transcriptomics should allow the definition of these networks through the analysis of cell-specific transcriptional signatures. Here we test this principle by applying an analogue to comparative anatomy at the cellular level, searching for conserved transcriptional signatures, or conserved small gene-regulatory networks (GRNs) on root hairs (RH) and pollen tubes (PT), two filamentous apical growing cells that are a striking example of conservation of structure and function in plants.', 'We developed a new method for isolation of growing and mature root hair cells, analysed their transcriptome by microarray analysis, and further compared it with pollen and other single cell transcriptomics data. Principal component analysis shows a statistical relation between the datasets of RHs and PTs which is suggestive of a common transcriptional profile pattern for the apical growing cells in a plant, with overlapping profiles and clear similarities at the level of small GTPases, vesicle-mediated transport and various specific metabolic responses. Furthermore, cis-regulatory element analysis of co-regulated genes between RHs and PTs revealed conserved binding sequences that are likely required for the expression of genes comprising the apical signature. This included a significant occurrence of motifs associated to a defined transcriptional response upon anaerobiosis.
Answer: Our results suggest that maintaining apical growth mechanisms synchronized with energy yielding might require a combinatorial network of transcriptional regulation. We propose that this study should constitute the foundation for further genetic and physiological dissection of the mechanisms underlying apical growth of plant cells.
[A]: Does transcriptional profiling of Arabidopsis root hairs and pollen define an apical cell growth signature?


[Q]: Context: Severe mitral regurgitation (MR) reduces left atrial thrombus formation in patients with mitral stenosis (MS) and atrial fibrillation (AF). Plasma D-dimer levels represent a biochemical marker for fibrinolytic activity in prothrombotic states. The prothrombotic burden in patients with mitral valve disease and/or AF was assessed using plasma D-dimer levels.', 'The study population included 89 patients with mitral valve disease, 21 with AF but normal valves, and 15 healthy controls. The mitral valve group was subdivided into patients with MS (n = 27), severe MR (n = 26), and MS with concomitant with severe MR (MS/MR; n = 36). These subgroups were further subdivided according to the atrial rhythm (sinus rhythm (SR)+AF).', 'The mean left atrial size was increased in all groups with cardiac disease. D-dimer levels were highest in the MS+AF subgroup (527 +/- 134 microg/l). Patients with MS+AF, MS+SR, and nonvalvular AF had significantly higher D-dimer levels than controls (p < 0.01, by ANOVA). Patients with MR had normal levels of D-dimer. The atrial rhythm did not influence D-dimer levels in the MS/MR subgroup, or in the pure MR subgroup (p = NS).
Answer: Plasma D-dimer levels correlated with the embolic risk in mitral valve disease and non-valvular AF. The highest levels were found in patients with MS+AF and non-valvular AF. Severe MR decreased the D-dimer levels in MS and/or AF to control levels.
[A]: Does mitral regurgitation reduce systemic coagulation activity in patients with rheumatic heart disease?


[Q]: Context: The endogenous opioid system has been reportedly implicated in tobacco/nicotine dependence.', 'We examined the genetic effects of eight SNPs in opioid receptor-related genes on smoking status and smoking-related traits in Japanese.', 'The genotypic and allelic variations of the rs2229205 SNP in the OPRL1 gene were significantly associated with smoking status, but no significant differences were found in the genetic variations of any of the SNPs with regard to smoking-related traits. The rs2229205 SNP did not show high linkage disequilibrium with the other SNPs in the linkage disequilibrium block that contained the SNP.
Answer: The rs2229205 SNP in the OPRL1 gene may be a genetic factor that contributes to individual differences in the vulnerability to smoking in Japanese individuals.
[A]:
Is nociceptin/orphanin FQ receptor gene variation associated with smoking status in Japanese?