RESUMO
GPR4 is a proton-sensing G protein-coupled receptor highly expressed in vascular endothelial cells and has been shown to potentiate intestinal inflammation in murine colitis models. Herein, we evaluated the proinflammatory role of GPR4 in the development of colitis-associated colorectal cancer (CAC) using the dextran sulfate sodium (DSS) and azoxymethane (AOM) mouse models in wild-type and GPR4 knockout mice. We found that GPR4 contributed to chronic intestinal inflammation and heightened DSS/AOM-induced intestinal tumor burden. Tumor blood vessel density was markedly reduced in mice deficient in GPR4, which correlated with increased tumor necrosis and reduced tumor cell proliferation. These data demonstrate that GPR4 ablation alleviates intestinal inflammation and reduces tumor angiogenesis, development, and progression in the AOM/DSS mouse model.
RESUMO
CASE: A 4-year-old boy sustained an accidental self-inflicted gunshot wound to the left forearm. Radiographs revealed a comminuted mid-diaphyseal ballistic radius fracture with a critical-sized bone defect. The fracture was treated with the placement of a flexible intramedullary nail and antibiotic cement spacer, followed by second-stage bone grafting and open reduction and internal fixation of the radius 6 weeks later. Four months after the second-stage procedure, the radial defect healed appropriately without complications. CONCLUSION: In this case of a pediatric comminuted mid-diaphyseal radius fracture with bone loss, the induced membrane technique resulted in healing across a critical-sized bone defect.