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: Interferon (IFN)-γ is a major cytokine produced by immune cells that plays diverse roles in modulating both the immune system and bone metabolism, but its role in autogenous bone grafting remains unknown. Here, we present that local IFN-γ administration improved the efficacy of autogenous bone graft treatment in an experimental rat model.', 'An autogenous bone graft model was prepared with critically sized rat calvariae defects. Four weeks (w) after bone graft implantation, rats were treated locally with IFN-γ or were not treated. The effect of IFN-γ on bone formation was evaluated for up to 8w with micro-computed tomography, quantitative histomorphometry, and Von Kossa staining. Osteoclastogenesis was assessed by tartrate-resistant acid phosphatase staining. Immunohistochemistry staining or quantitative polymerase chain reactions were used to estimate the expression of osteoclast differentiation factor and inflammatory cytokines including tumor necrosis factor (TNF)-α, a well-known stimulant of osteoclastogenesis and an inhibitor of osteoblast activity, in defects.', 'Newly formed bone gradually replaced the autogenous bone grafts within 4w, although severe bone resorption with osteoclastogenesis and TNF-α expression occurred after 6w in the absence of IFN-γ administration. IFN-γ administration markedly attenuated bone loss, osteoclastogenesis, and TNF-α expression, while it enhanced bone formation at 8w.
Answer: Local IFN-γ administration promoted bone formation in autogenous bone grafts possibly via regulating osteoclastogenesis and TNF-α expression. The data provide insights into the potential roles of IFN-γ in autogenous bone grafting.

SOLUTION: Does interferon-γ enhance the efficacy of autogenous bone grafts by inhibiting postoperative bone resorption in rat calvarial defects?

PROBLEM: Context: Therapeutic angiogenesis is a promising strategy for treating ischemia. Our previous work showed that endogenous endothelial tissue factor (TF) expression induces intracrine signaling and switches-on angiogenesis in microvascular endothelial cells (mECs). We have hypothesized that activated mECs could exert a further paracrine regulation through the release of TF-rich microvascular endothelial microparticles (mEMPs) and induce neovascularization of ischemic tissues.', 'Here, we describe for the first time that activated mECs are able to induce reparative neovascularization in ischemic zones by releasing TF-rich microparticles. We show in vitro and in vivo that mEMPs released by both wild-type and TF-upregulated-mECs induce angiogenesis and collateral vessel formation, whereas TF-poor mEMPs derived from TF-silenced mECs are not able to trigger angiogenesis. Isolated TF-bearing mEMPs delivered to nonperfused adductor muscles in a murine hindlimb ischemia model enhance collateral flow and capillary formation evidenced by MRI. TF-bearing mEMPs increase angiogenesis operating via paracrine regulation of neighboring endothelial cells, signaling through the β1-integrin pathway Rac1-ERK1/2-ETS1 and triggering CCL2 (chemokine [C-C motif] ligand 2) production to form new and competent mature neovessels.
Answer: These findings demonstrate that TF-rich mEMPs released by microvascular endothelial cells can overcome the consequences of arterial occlusion and tissue ischemia by promoting postischemic neovascularization and tissue reperfusion.

SOLUTION: Do angiogenic microvascular endothelial cells release microparticles rich in tissue factor that promotes postischemic collateral vessel formation?

PROBLEM: Context: Oxidative stress may be involved in occurrence of postoperative delirium (POD) and cognitive dysfunction (POCD). 8-iso-Prostaglandin F2α (8-iso-PGF2α), an isoprostane derived from arachidonic acid via lipid peroxidation, is considered a gold standard for measuring oxidative stress. The present study aimed to investigate the ability of postoperative plasma 8-iso-PGF2α levels to predict POD and POCD in elderly patients undergoing hip fracture surgery.', 'Postoperative plasma 8-iso-PGF2α levels of 182 patients were measured by an enzyme-linked immunosorbent assay. We assessed the relationships between plasma 8-iso-PGF2α levels and the risk of POD and POCD using a multivariate analysis.', 'Plasma 8-iso-PGF2α levels and age were identified as the independent predictors for POD and POCD. Based on areas under receiver operating characteristic curve, the predictive values of 8-iso-PGF2α were obviously higher than those of age for POD and POCD. In a combined logistic-regression model, 8-iso-PGF2α significantly enhanced the areas under curve of age for prediction of POD and POCD.
Answer: Postoperative plasma 8-iso-PGF2α levels may have the potential to predict POD and POCD in elder patients undergoing hip fracture surgery.

SOLUTION:
Are postoperative plasma 8-iso-prostaglandin F2α levels associated with delirium and cognitive dysfunction in elderly patients after hip fracture surgery?