TASK DEFINITION: Given a passage with a context and an answer, 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: Context: Ischemic preconditioning (IPC) mitigates ischemia-reperfusion (I/R) injury in experimental models. However, the clinical significance of this protection has been unclear and a mortality reduction has not been previously reported in noncardiac models. This study examined the local and remote protection afforded by skeletal muscle IPC and sought to determine the significance of this protection on mortality.', "Mice subjected to 2 h hindlimb ischemia/24 h reperfusion (standard I/R injury) were compared with those undergoing a regimen of two 20-min cycles of IPC followed by standard I/R injury. Local injury was assessed via gastrocnemius histology, and remote injury was evaluated via intestinal histology and pulmonary neutrophil infiltration (n = 7). Mortality was compared in parallel groups for 1 week (n = 6). Groups were analyzed using an unpaired Student's t-test for gastrocnemius and pulmonary injury, and a Mann-Whitney rank sum test for intestinal injury. Mortality differences were interpreted through a hazard ratio.", 'Significant protection was observed in preconditioned animals. There was a 35% local injury reduction in skeletal muscle (71.2% versus 46.0%, P < 0.01), a 50% reduction in remote intestinal injury (2.3 versus 1.1, P < 0.01), and a 43% reduction in remote pulmonary injury (14.9 versus 8.5, P < 0.01) compared with standard injury controls. Preconditioned animals were also significantly protected from mortality, demonstrating a 66.7% survival at 1 wk compared with 0% survival after standard injury alone (hazard ratio 0.20, 95% CI: 0.02-0.59).
Answer: We have developed a murine model of IPC that demonstrates local and remote protection against I/R injury, and exhibits significant mortality reduction. This model demonstrates the powerful effect of IPC on local and remote tissues and will facilitate further study of potential mechanisms and therapies.

SOLUTION: Does ischemic preconditioning of skeletal muscle mitigate remote injury and mortality?

PROBLEM: Context: Mast cells have been associated with obliterative bronchiolitis (OB) in human pulmonary allografts, although their role in the development of OB remains unknown.', 'In this study, we evaluated the role of mast cells in pulmonary allograft rejection using an orthotopic rat pulmonary allograft model that utilizes chronic aspiration of gastric fluid to reliably obtain OB. Pulmonary allograft recipients (n = 35) received chronic aspiration of gastric fluid with (n = 10) and without (n = 16) treatment with a mast cell membrane stabilizer, cromolyn sodium, or chronic aspiration with normal saline (n = 9) as a control.', 'The acute graft injury associated with long ischemic time in the model (6 hours total ischemic time; typical acute graft injury rate ~30%) was apparently blocked by cromolyn, because peri-operative mortality associated with the acute graft injury was not observed in any of the animals receiving cromolyn (p = 0.045). Further, the rats receiving cromolyn developed significantly fewer OB lesions than those treated with gastric fluid alone (p < 0.001), with a mean reduction of 46% of the airways affected.
Answer: These findings provide impetus for further studies aimed at elucidating the effects of cromolyn and the role of mast cells in pulmonary allotransplantation.

SOLUTION: Does cromolyn ameliorate acute and chronic injury in a rat lung transplant model?

PROBLEM: Context: Severity of rheumatoid arthritis and progression of radiographic joint damage have decreased over the last decades.', 'To examine whether this trend is attributable to an underlying trend towards milder disease or to improved treatment.', 'The study used an inception cohort of patients with early rheumatoid arthritis seen at the Wichita Arthritis Center, Wichita, Kansas, USA, since 1973 and monitored prospectively since their first clinic visit through clinical, radiographic, laboratory, demographic and self-reported data. The radiographic disease progression in patients with disease onset in the 1970s, 1980s and 1990s was compared using a multivariate regression model for longitudinal data. The analysis was adjusted for differences in baseline predictors, type of disease-modifying antirheumatic drugs (DMARDs) and steroid use.', '418 patients with rheumatoid arthritis with radiographic follow-up were included. Patients in earlier decades used fewer DMARDs, had longer disease durations and higher tender joint counts at their first visit. Other important predictors of disease progression did not differ significantly between decades of disease onset. The unadjusted rates of radiographic progression differed between decades (analysis of variance, p = 0.01), with a significant trend towards less radiographic progression in more recent times (trend, p<0.001). However, after adjusting for DMARD use, steroid use and baseline predictors, differences between decades vanished (analysis of variance, p = 0.40) and the trend towards less radiographic progression disappeared (trend, p = 0.45).
Answer: These results suggest that the observed trend towards milder disease in rheumatoid arthritis is attributable to more effective antirheumatic treatment and not to a secular trend.

SOLUTION:
Are progression of radiographic joint damage in different eras : trends towards milder disease in rheumatoid arthritis attributable to improved treatment?