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.
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Question: 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.

Answer: Does preoperative anemia increase postoperative morbidity in elective cranial neurosurgery?


Question: 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.

Answer: Are dNA methylation subgroups in melanoma associated with proliferative and immunological processes?


Question: Context: Nonalcoholic steatohepatitis (NASH) is associated with cirrhosis and hepatocellular carcinoma. Reactive oxygen species (ROS) and reactive nitrogen species (RNS) play key roles in the development of the disease. However, the therapeutic target of NASH has not been fully defined and new treatments are needed. We investigated the protective effects of the antioxidant indole-derived NecroX-7 in a NASH mouse model using leptin-deficient ob/ob and methionine- and choline-deficient (MCD) diet-fed ob/ob mice.', 'Six-week-old male mice were divided into three groups: ob/+ mice, ob/ob mice treated with vehicle and ob/ob mice treated daily with NecroX-7 (20 mg/kg) for 4 weeks. To study the effects of NecroX-7 in a fibrosis model, NASH was induced by feeding ob/ob mice an MCD diet. The effects of NecroX-7 on NASH progression were evaluated using biochemical, histological and molecular markers.', 'NecroX-7-treated ob/ob mice had a marked decrease in serum aspartate aminotransferase and alanine transaminase compared with vehicle-treated controls. Interestingly, hepatic steatosis and lipid peroxidation were significantly improved by NecroX-7 treatment. NecroX-7 inhibited tert-butylhydroperoxide- and H2 O2 -induced mitochondrial ROS/RNS in primary hepatocytes and attenuated mitochondrial dysfunction in vitro and in vivo. Furthermore, NecroX-7-treated mice exhibited fewer infiltrating macrophages and reduced hepatic tumour necrosis factor-alpha expression. Hepatic fibrosis in MCD-fed ob/ob mice was significantly decreased by NecroX-7 treatment.
Answer: NecroX-7 treatment improved hepatic steatosis and fibrosis in murine NASH models. These effects occurred through the suppression of whole-cell ROS/RNS and inflammatory responses and suggest that NecroX-7 has a potential therapeutic benefit in steatohepatitis.

Answer:
Does the indole derivative NecroX-7 improve nonalcoholic steatohepatitis in ob/ob mice through suppression of mitochondrial ROS/RNS and inflammation?