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: Preoperative anemia may affect postoperative mortality and morbidity following elective cranial operations.', 'The American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database was used to identify elective cranial neurosurgical cases (2006-2012). Morbidity was defined as wound infection, systemic infection, cardiac, respiratory, renal, neurologic, and thromboembolic events, and unplanned returns to the operating room. For 30-day postoperative mortality and morbidity, adjusted odds ratios (ORs) were estimated with multivariable logistic regression.', 'Of 8015 patients who underwent elective cranial neurosurgery, 1710 patients (21.4%) were anemic. Anemic patients had an increased 30-day mortality of 4.1% versus 1.3% in non-anemic patients (P < 0.001) and an increased 30-day morbidity rate of 25.9% versus 14.14% in non-anemic patients (P < 0.001). The 30-day morbidity rates for all patients undergoing cranial procedures were stratified by diagnosis: 26.5% aneurysm, 24.7% sellar tumor, 19.7% extra-axial tumor, 14.8% intra-axial tumor, 14.4% arteriovenous malformation, and 5.6% pain. Following multivariable regression, the 30-day mortality in anemic patients was threefold higher than in non-anemic patients (4.1% vs 1.3%; OR = 2.77; 95% CI: 1.65-4.66). The odds of postoperative morbidity in anemic patients were significantly higher than in non-anemic patients (OR = 1.29; 95% CI: 1.03-1.61). There was a significant difference in postoperative morbidity event odds with a hematocrit level above (OR = 1.07; 95% CI: 0.78-1.48) and below (OR = 2.30; 95% CI: 1.55-3.42) 33% [hemoglobin (Hgb) 11 g/dl].
Answer: Preoperative anemia in elective cranial neurosurgery was independently associated with an increased risk of 30-day postoperative mortality and morbidity when compared to non-anemic patients. A hematocrit level below 33% (Hgb 11 g/dl) was associated with a significant increase in postoperative morbidity.

A: Does preoperative anemia increase postoperative morbidity in elective cranial neurosurgery?
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Q: Context: DNA methylation at CpG dinucleotides is modified in tumorigenesis with potential impact on transcriptional activity.', 'We used the Illumina 450 K platform to evaluate DNA methylation patterns of 50 metastatic melanoma tumors, with matched gene expression data.', 'We identified three different methylation groups and validated the groups in independent data from The Cancer Genome Atlas. One group displayed hypermethylation of a developmental promoter set, genome-wide demethylation, increased proliferation and activity of the SWI/SNF complex. A second group had a methylation pattern resembling stromal and leukocyte cells, over-expressed an immune signature and had improved survival rates in metastatic tumors (p < 0.05). A third group had intermediate methylation levels and expressed both proliferative and immune signatures. The methylation groups corresponded to some degree with previously identified gene expression phenotypes.
Answer: Melanoma consists of divergent methylation groups that are distinguished by promoter methylation, proliferation and content of immunological cells.

A: Are dNA methylation subgroups in melanoma associated with proliferative and immunological processes?
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Q: Context: Pharmacoresistance is a common problem hindering treatment of epilepsy. A possible cause for this resistance is the overexpression of efflux drug transporters, e.g. P-glycoprotein (P-gp), which may decrease extracellular antiepileptic drugs levels in brains of intractable epilepsy patients. Another transmembrane drug transporter is the organic anion transporting polypeptide 2 (Oatp2), which is colocalized with P-gp in many polarized tissues. However, a role for Oatp2 in the development of multidrug resistance has not been established. In the present work, we investigated the expression of drug transporters Oatp2 and P-gp in brain, liver and kidney of rats with chronic epilepsy induced by lithium-pilocarpine.', 'Chronic epilepsy was elicited after status epilepticus (SE) induced by lithium-pilocarpine in adult Wistar rats. Following SE, expression of Oatp2 and P-gp protein was detected by immunohistochemistry and Western blot analysis and messenger RNA (mRNA) using reverse transcription polymerase chain reaction (RT-PCR). Levels of the drug transporters were compared in brain, liver and kidney of chronic epileptic and control rats.', 'Both Oatp2 and P-gp were expressed in the brain, liver and kidney but predominantly in the brain. In the brain, Oatp2 and P-gp immunopositive cells were observed in brain capillary endothelium and choroid plexus epithelium. Compared with control rats, Oatp2 protein expression in brain was significantly decreased, while P-gp was obviously increased in chronic epileptic rats. P-gp mRNA was also significantly higher in brains of chronic epileptic rats, whereas the expression of Oatp2 did not change. Organic anion transporting polypeptide 2 and P-gp did not change at the mRNA or protein level with epilepsy in the liver or kidney.
Answer: Organic anion transporting polypeptide 2 and P-gp colocalized in tissues that are important in drug absorption, metabolism and excretion. Seizures seem to induce the cerebral changes of P-gp and Oatp2. However, the changes of expression of two transporters exhibit the opposite trend. Organic anion transporting polypeptide 2 might play a different role than P-gp in intractable epilepsy. Our data provide a basis for the assessment of the role of uptake transporters and efflux pumps in the development of intractable epilepsy.

A:
Are drug transporters altered in brain , liver and kidney of rats with chronic epilepsy induced by lithium-pilocarpine?
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