TASK DEFINITION: In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
PROBLEM: Context: Obstructive sleep apnea (OSA) is a common disorder characterized by chronic intermittent hypoxia (CIH). OSA is prevalent in obese subjects and is associated with endothelial dysfunction and cardiovascular disorders. We tested the hypothesis that the deleterious effects of IH could be further modulated by diet-induced obesity.', 'Thirty adult (8-10 weeks) male C57BL/6J mice were divided into four groups. Mice were subjected to CIH or intermittent air (IA) for 12h a day and fed either a high fat (HF) or a low fat control diet (CD) for 6weeks. We analyzed endothelial function using a wire myograph, and measured markers of oxidative stress (plasma malondialdehyde (MDA) and total antioxidant capacity (TAC)) using colorimetrical assays. We also measured C-reactive protein (CRP) using ELISA and endothelial nitric oxide (eNOS) gene expression using real time PCR.', 'Stimulated endothelial dependent dilation was significantly impaired only in the group fed high fat diet and subjected to CIH (Emax: HFIH 78±2%, p<0.0001) when compared to the other groups (Emax: HFIA 95±0.7%, CDIH 94±2%, CDIA 97±1%). Also basal endothelial dependant dilation was attenuated in the HFIH group compared to the HFIA group (Emax: HFIH: 179±10% vs. HFIA: 149±11% in the presence of L-NAME). Levels of MDA were elevated in the CDIH group when compared to CDIA (0.68±0.04 vs. 0.41±0.03 μM, p<0.05) but were greatest in the HFIH group (0.83±0.08 μM, p<0.05). However, there was no significant increase in MDA levels in the HFIA group (0.45±0.03 μM, p=NS) when compared to all other groups. Similar effects were observed with CRP levels; CRP levels were significantly higher in the CDIH group compared with intermittent air (10.39±0.38 vs. 8.70±0.21 μg/ml, p<0.05) but the HFIH had the greatest levels of CRP (11.87±0.31 μg/ml, p<0.05). In the HFIA group, CRP levels were not elevated (9.96±0.37 μg/ml, p=NS). Nevertheless, total antioxidant capacity and eNOS gene expression were not significantly different in the groups.\Question: Does chronic intermittent hypoxia cause endothelial dysfunction in a mouse model of diet-induced obesity?

SOLUTION: CIH caused endothelial dysfunction in mice fed an obesogenic diet. Inflammation and oxidative stress were increased in CIH and an obesogenic diet exacerbated these effects.

PROBLEM: Context: Statin therapy in nonsurgical patient populations is associated with a significant reduction in adverse cardiovascular events, including death, myocardial infarction (MI), and stroke. Recently, statin therapy was shown to be associated with a reduced incidence of postoperative mortality in patients undergoing major noncardiac vascular surgery. We investigated the influence of preoperative statin therapy on adverse outcomes after primary coronary artery bypass graft (CABG) surgery.', 'A retrospective cohort study of patients undergoing primary CABG surgery with cardiopulmonary bypass (CPB) (n=1663) between January 1, 2000 and December 31, 2001 at the Texas Heart Institute was performed. Patients were classified into 2 groups: patients receiving preoperative statin therapy (n=943) and patients not receiving preoperative antihyperlipidemic therapy (n=720). To determine if preoperative statin therapy was independently associated with a reduction in the risk of adverse postoperative outcomes, multivariate stepwise logistic regression was performed controlling for patient demographics, medical history, and preoperative medications. Multivariate logistic regression analysis demonstrated that preoperative statin therapy was independently associated with a significant reduction ( approximately 50%) in the risk of 30-day all-cause mortality (3.75% versus 1.80%; P<0.05). The adjusted odds ratio for early mortality in patients receiving preoperative statin therapy compared with patients not receiving antihyperlipidemic agents was 0.53 (95% CI, 0.28 to 0.99). Statin therapy was not independently associated with a reduced risk of postoperative MI, cardiac arrhythmias, stroke, or renal dysfunction. In an attempt to further control for selection bias related to the choice of therapy, multivariate analysis of a propensity-matched cohort of 1362 patients revealed that preoperative statin therapy was independently associated with a significant reduction in the composite endpoint of 30-day all-cause mortality and stroke (7.1% versus 4.6%; P<0.05).\Question: Are statins associated with a reduced incidence of perioperative mortality after coronary artery bypass graft surgery?

SOLUTION: Preoperative statin therapy may reduce the risk of early mortality after primary CABG surgery with CPB.

PROBLEM: Context: The purpose of this study was to determine the effects of enamel matrix derivative on mRNA expression of markers related to periodontal healing.', 'Murine osteoprogenitor cells (MC3T3-E1) were grown for 12 and 16 days in mineralization media and stimulated with 100 microg/mL Emdogain (EMD). Cell cultures treated with 2% and 10% fetal calf serum (FCS) served as control. The mRNA expression of bone sialoprotein (BSP), osteopontin (OPN), and runt-related protein 2 (Runx2) was analyzed by real-time polymerase chain reaction. One-way analysis of variance was used for statistical analysis.', 'Stimulation with EMD significantly (P < .01) enhanced mRNA expression of BSP up to 13.9-fold and of OPN up to 3.2-fold at day 16 compared with the 2% FCS control. The expression of mRNA for transcription factor Runx2 was not significantly changed.\Question: Does stimulation of osteoblasts with Emdogain increase the expression of specific mineralization markers?

SOLUTION:
The beneficial effects seen in periodontal regeneration after treatment with EMD may be related to an increase of the mineralization markers BSP and OPN at mRNA level.