TASK DEFINITION: Given a passage, 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.
PROBLEM: Although the majority of evidence does not support association between Helicobacter pylori infection and ischaemic heart disease, the nature of this relationship may differ when virulence of the infecting strains are examined.', 'The prevalence of IgG antibody evidence of infection with CagA positive stains of H. pylori was investigated in stored plasma samples from 259 cases of myocardial infarction (aged 25-70 years, 74 males) and 259 population based controls from the same area in Northern Ireland. Two-hundred and seventy (52.1%) subjects were seropositive for anti-CagA IgG. CagA seropositivity was more common in cases than in controls: 56.4 vs 47.9%, odds ratio for seropositivity in cases (95% CI) 1.41 (1.00, 1.99). Substantial attenuation of this relationship occurred on adjustment for age, sex, number of siblings, smoking and measures of socio-economic status: odds ratio (95% CI) 1.16 (0.79, 1.70). A similar pattern was seen for seropositivity for all H. pylori strains.

SOLUTION: Is infection with virulent strains of Helicobacter pylori associated with ischaemic heart disease : evidence from a population-based case-control study of myocardial infarction?

PROBLEM: Evaluation of right ventricular (RV) function in patients with pulmonary regurgitation (PR) after tetralogy repair remains challenging because of abnormal RV loading conditions.', 'We examined 124 patients, aged 21+/-11.4 years, who had tetralogy repair at 3.7+/-3.5 years. By Doppler echocardiography, 33 patients had mild, 22 moderate, and 69 severe PR; 55 had significant tricuspid regurgitation (TR). Myocardial velocities, myocardial acceleration during isovolumic contraction (IVA), strain, and strain rate were measured at RV and LV base. Tricuspid valve annulus was measured in a 4-chamber view. QRS, QT, and JT intervals and their dispersions were measured from 12-lead electrocardiogram. IVA in the RV was lower in all patients compared with controls (0.8+/-0.4 versus 1.8+/-0.5, P<0.0001) and correlated with the severity of PR (r=-0.43, P<0.0001), whereas myocardial velocities, and strain/strain rate did not. LV IVA correlated with PR (r=-0.32, P<0.001) and with RV IVA (r=0.28, P<0.003). Patients with severe PR had a higher incidence of TR (r=0.69, P<0.0001) and lower RV IVA (1.0+/-0.4 versus 0.6+/-0.3, P<0.0001), a larger tricuspid valve ring diameter (P<0.0001), and prolonged electrical depolarization (P<0.001). Age at surgery or examination did not correlate with PR and with RV function assessed by IVA. In the RV, IVA correlated inversely with QRS duration (P<0.01).

SOLUTION: Is pulmonary regurgitation an important determinant of right ventricular contractile dysfunction in patients with surgically repaired tetralogy of Fallot?

PROBLEM: Endoscopic surveillance for adenocarcinoma in patients with Barrett's esophagus is costly, with one cancer detected every 48-441 patient years of follow up. Genetic abnormalities, including loss of heterozygosity at sites of tumor suppressor genes, have been detected in malignant and premalignant Barrett's esophagus. The aim of this prospective study was to determine if loss of heterozygosity analysis could identify patients with Barrett's esophagus at greatest risk of adenocarcinoma, for whom endoscopic surveillance is most appropriate.", "Loss of heterozygosity analysis was performed on endoscopic biopsies from 48 patients as part of a Barrett's surveillance program using 14 microsatellite markers shown previously to detect loss of heterozygosity in more than 30% of esophageal adenocarcinomas. Patients were followed up endoscopically for a median of 5 years.", 'Loss of heterozygosity was detected in nine patients. Three patients with loss of heterozygosity on chromosome 5q or 9p did not progress beyond metaplasia. Loss of heterozygosity at 17p11.1-p13 was detected in six patients, all of whom demonstrated dysplasia and/or carcinoma during follow up (four low-grade dysplasia, one high-grade dysplasia and one adenocarcinoma).

SOLUTION:
Does loss of heterozygosity on chromosome 17p predict neoplastic progression in Barrett 's esophagus?