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: Despite much clinical experience, there are few published accounts of the surgical manifestations of HIV/AIDS in children and still fewer guidelines for the best or most appropriate treatment. Our primary objective was to document the incidence of HIV infection in children who presented with a surgical emergency to a major pediatric surgical unit in South Africa. If possible, we aimed to provide a description of the impact of the disease in a surgical pediatric population and to raise awareness of the mode of presentation of HIV to the pediatric surgeon in a developing nation, now that specific antiretroviral therapies are available.', 'This was a prospective observational study of consecutive surgical emergency admissions to the Division of Paediatric Surgery at the University of the Witwatersrand, Johannesburg, South Africa, between April 1 and May 31, 2005. Consent for inclusion in the study was sought in all cases. The clinical profile of children presenting during the study period was recorded. If relevant, permission was sought from the parent/guardian to undertake HIV status testing if this were not already known.', 'Three hundred ninety-one children were admitted as emergency cases during the study period. Thirty-seven (9.5%) of 391 were excluded, because consent could not be obtained, leaving 354 children. Ages ranged between 1 day and 17 years, with a median age of 3 years. The diagnosis in most was trauma/burns (42%) and abdominal emergencies (27%). Infections occurred in 13% of these patients. Human immunodeficiency virus status was already known in 10 (3%) of 354 patients, and only 18 (5%) of 344 children were tested; of these, 10 (55%) were positive. As expected, the predominant surgical presentation of HIV positive children was sepsis. The prevalence of HIV/AIDS in those children not tested is unknown.

SOLUTION: Are surgeons failing to recognize children with HIV infection?

PROBLEM: 5-hydroxytryptamine-3 (5-HT3) receptor antagonists inhibit gastric phase-3 motor activity in the dog. This study examined the role of 5-HT3 receptors in the generation of gastric phase 3 of the migrating motor complex in humans.', 'Interdigestive motor activity was recorded manometrically in 16 subjects before and after administration of ondansetron, a selective 5-HT3 receptor antagonist. Plasma motilin values were also assayed in 7 individuals. The incidence of gastric activity fronts before and after ondansetron was compared with a control group that had not received ondansetron. The ability of erythromycin to induce a gastric activity front in the presence of ondansetron was also evaluated in 7 subjects.', 'The incidence of gastric activity fronts was 69% before ondansetron vs. 19% after ondansetron. In contrast, in the control group there was no significant change in the incidence of gastric activity fronts over time. Activity fronts preceding ondansetron were associated with motilin peaks while activity fronts after ondansetron were not. Despite the previous administration of ondansetron, erythromycin induced gastric activity fronts in 89% of cases.

SOLUTION: Are 5-hydroxytryptamine-3 receptors involved in the initiation of gastric phase-3 motor activity in humans?

PROBLEM: The goal was to test the hypothesis that extremes of PaCO2 during the first 4 days after birth are associated with severe intraventricular hemorrhage (grades 3 and 4).', 'A single-center retrospective review of clinical and blood gas data in the first 4 postnatal days for 849 infants with birth weights of 401 to 1250 g was performed. The univariate and multivariate relationships of severe intraventricular hemorrhage with maximal and minimal PaCO2, PaCO2 averaged over time (time-weighted PaCO2), and measures of PaCO2 fluctuation (SD of PaCO2 and difference in PaCO2 [maximum minus minimum]) were assessed.', 'Birth weight (mean +/- SD) was 848 +/- 212 g, and the median gestational age was 26 weeks. Infants with severe intraventricular hemorrhage had higher maximal PaCO2 (median: 72 vs 59 mm Hg) and time-weighted PaCO2 (mean: 49 vs 47 mm Hg) values but lower minimal PaCO2 values (32 vs 37 mm Hg). High PaCO2, low PaCO2, SD of PaCO2, and difference in PaCO2 predicted severe intraventricular hemorrhage, but time-weighted average PaCO2 was not as predictive.

SOLUTION:
Are both extremes of arterial carbon dioxide pressure and the magnitude of fluctuations in arterial carbon dioxide pressure associated with severe intraventricular hemorrhage in preterm infants?