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: Lung cancer is the most important cause of cancer mortality worldwide, but the underlying mechanisms of this disease are not fully understood. Copy number variations (CNVs) are promising genetic variations to study because of their potential effects on cancer.', 'Here we conducted a pilot study in which we systematically analyzed the association of CNVs in two lung cancer datasets: the Environment And Genetics in Lung cancer Etiology (EAGLE) and the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial datasets. We used a preestablished association method to test the datasets separately and conducted a combined analysis to test the association accordance between the two datasets. Finally, we identified 167 risk SNP loci and 22 CNVs associated with lung cancer and linked them with recombination hotspots. Functional annotation and biological relevance analyses implied that some of our predicted risk loci were supported by other studies and might be potential candidate loci for lung cancer studies.\Question: Does combined analysis with copy number variation identify risk loci in lung cancer?

SOLUTION: Our results further emphasized the importance of copy number variations in cancer and might be a valuable complement to current genome-wide association studies on cancer.

PROBLEM: Context: Approximately 50% of subjects with essential hypertension (EH) are insulin resistant, and this defect in insulin action could contribute to increased cardiovascular disease (CVD) risk in these patients. To test this hypothesis, we attempted to see if there was a link between insulin resistance (IR) and carotid intimal medial thickness (IMT), an early index of CVD, in patients with essential hypertension.', 'Ultrasound quantification of carotid IMT was performed in 79 hypertensive patients, and 63 patients (31 m and 32 f), defined as being free of plaque (IMT < 1.3 mm), were further subdivided into normal (<1.0 mm) and thickened (1-1.3 mm) IMT groups. Subjects in the thickened IMT group were older and had significantly (p < 0.05) higher plasma concentrations of fasting insulin, nitric oxide (NO(x)) and intercellular adhesion molecule 1 (ICAM-1). However, the two groups were not significantly different in terms of blood pressure, overall or regional obesity, fasting lipid levels, uric acid, concentrations of other cellular adhesion molecules or levels of C-reactive protein. There were significant (p < 0.05) correlations in the whole population between IMT and age, fasting insulin and NO(x), and multiple regression analysis identified fasting insulin as an independent predictor of IMT.\Question: Do insulin resistance/compensatory hyperinsulinemia predict carotid intimal medial thickness in patients with essential hypertension?

SOLUTION: The presence of increased IMT is significantly related to several metabolic and endothelial abnormalities associated with IR/hyperinsulinemia, and fasting insulin independently predicts the thickness of the intima-media layer. These results support the view that CVD risk is greatest in those patients with essential hypertension who are also IR/hyperinsulinemic.

PROBLEM: Context: To determine whether bowel wall fibrosis can be detected in freshly resected human intestinal specimens based on ultrasound-derived shear wave speed.', "Seventeen intact (>3-cm) bowel segments (15 small and 2 large intestine) from 12 patients with known or suspected inflammatory bowel disease were procured immediately after surgical resection. Ultrasound shear wave elastography of the bowel wall was performed by two methods (Virtual Touch Quantification [VTQ] and Virtual Touch-IQ [VT-IQ]; Siemens Medical Solutions USA, Inc, Mountain View, CA). Eighteen short-axis shear wave speed measurements were acquired from each specimen: 3 from the 9-, 12-, and 3-o'clock locations for each method. Imaging was performed in two areas for specimens greater than 10 cm in length (separated by 5 cm). A gastrointestinal pathologist scored correlative histologic slides for inflammation and fibrosis. Differences in mean shear wave speed between bowel segments with low and high inflammation/fibrosis scores were assessed by a Student t test. Receiver operating characteristic curve analysis was performed.", 'High-fibrosis score (n = 11) bowel segments had a significantly greater mean shear wave speed than low-fibrosis score (n = 6) bowel segments (mean SD: VTQ, 1.59 0.37 versus 1.18 0.08 m/s; P= .004; VT-IQ, 1.87 0.44 versus 1.50 0.26 m/s; P= .049). There was no significant difference in mean shear wave speed between high-and low-inflammation score bowel segments (P > .05 for both VTQ and VT-IQ). Receiver operating characteristic curves showed areas under the curve of 0.91 (95% confidence interval, 0.67-0.99) for VTQ and 0.77 (95% confidence interval, 0.51-0.94) for VT-IQ in distinguishing low-from high-fibrosis score bowel segments.\Question: Does ultrasound shear wave elastography help discriminate low-grade from high-grade bowel wall fibrosis in ex vivo human intestinal specimens?

SOLUTION:
Ex vivo bowel wall shear wave speed measurements increase when transmural intestinal fibrosis is present.