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: Our objective was to study the direct effects of meconium on isolated umbilical artery and vein in vitro.', "Intact umbilical artery and vein rings were suspended in 5 ml organ baths containing kreb's solution (pH 7.2, 37 degrees C; bubbled with 2.5% oxygen and 8.07% carbon dioxide, balance nitrogen) for isometric tension recording. Meconium alone (final bath concentration 1%), centrifuged and filtered meconium, and meconium with the lipid fraction removed (separated into < 30,000 kd and > 30,000 kd) were added to the baths. Some vessels were also incubated in 1% meconium for 30 minutes, after which the meconium was washed out. Concentration-response curves to U46619 were obtained. The negative log of the concentration that evokes 50% of the maximal contraction was determined.", 'Umbilical artery and vein had no sustained response to meconium. Tension that developed by rings exposed to meconium was significantly less than control at all concentrations of U46619. There was some loss of the efficacy of meconium after centrifugation-filtration and washing out. Meconium without the lipid fraction had less inhibitory effect than did native meconium.

SOLUTION: Does meconium inhibit the contraction of umbilical vessels induced by the thromboxane A2 analog U46619?

PROBLEM: The Tonnis radiographic classification of developmental dysplasia of the hip (DDH) has been used as a prognostic indicator for patients with walking-age DDH. The International Hip Dysplasia Institute (IHDI) classification, a new radiographic classification system, has been proposed to be more reliable by its creators. We sought to validate its reliability using independent observers, to compare it to the Tonnis method, and to assess its prognostic significance in a large cohort of patients.', 'A consecutive series of walking-age DDH patients were examined radiographically and classified by the Tonnis and IHDI schemes by 3 independent observers. Interobserver agreement was determined using the Kappa method. Clinical data were collected on patients with regard to success of closed reduction, need for later pelvic osteotomy, and presence of subsequent radiographic avascular necrosis (AVN). The prognostic value of the Tonnis and IHDI classifications to predict these clinical outcomes was determined.', 'A total of 287 hips were available for analysis of the classification schemes. In total, 235 hips underwent attempted closed reduction and were eligible for analysis of successful closed reduction, and 131 hips had >4-year follow-up and were utilized for analysis of late pelvic osteotomy and AVN. Both classifications showed excellent interobserver reliability and in general, there was nonstatistically significant better reliability for the IHDI versus the Tonnis classification. In multivariate analysis, both IHDI and Tonnis classifications were found to be predictive of successful closed reduction and need for late pelvic osteotomy. Both methods showed trends toward being predictive of AVN rate, without statistical significance.

SOLUTION: Is a New Radiographic Classification System for Developmental Hip Dysplasia Reliable and Predictive of Successful Closed Reduction and Late Pelvic Osteotomy?

PROBLEM: To determine the cellular mediators of antigen-induced arthritis (AIA) and the relative contribution of members of the interleukin-6 (IL-6) family and tumor necrosis factor (TNF) in AIA.', 'AIA was induced in mice deficient in T and B lymphocytes, IL-6 (IL-6(-/-)), TNF (TNF(-/-)), IL-11 receptor, and oncostatin M receptor, by immunization with methylated bovine serum albumin (mBSA) followed 7 days later by intraarticular injection of mBSA. Arthritis severity was assessed histologically, and T lymphocyte responses were assessed in vitro. Anti-TNF neutralizing antibody was administered to wild-type mice during AIA. Bone marrow osteoclasts were generated in vitro via culture with RANKL and macrophage colony-stimulating factor.', 'AIA was dependent on CD4+ T lymphocytes, but not CD8+ T lymphocytes or B cells. IL-6(-/-) mice had reduced AIA severity and fewer osteoclasts at sites of bone erosion. This protective effect was not seen with a deficiency of other IL-6 family members and was similar to that in TNF(-/-) mice or wild-type mice receiving TNF blockade treatment. IL-6(-/-) CD4+ T lymphocytes from draining lymph nodes had reduced antigen-induced proliferation and produced less IL-17 and less RANKL, relative to osteoprotegerin, than cells from wild-type mice. Bone marrow from IL-6(-/-) mice generated fewer osteoclasts in vitro than bone marrow from either wild-type or TNF(-/-) mice.

SOLUTION:
Does interleukin-6 modulate production of T lymphocyte-derived cytokines in antigen-induced arthritis and drives inflammation-induced osteoclastogenesis?