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Bone loss after severe burn injury is well established, and is thought to be a consequence of the severe hyper-metabolic response as well as changes in cytokine and glucocorticoid levels that decrease bone synthesis and increase rate of loss. However, 90% of presentations are for non-severe burns which do not elicit this response. Little is known about whether these non-severe injuries may also affect bone tissue, and whether other mechanisms may be involved. To investigate whether bone loss occurs after a non-severe burn injury we used a mouse model of an approximately 8% total body surface area (TBSA) full-thickness burn and micro-CT. We also assessed whether blocking TNF-α after a burn injury by administration of an antibody could modulate the impacts of the burn on bone tissue. There was a significant loss of trabecular bone volume of (3.27% compared to 5.27%, p=0.0051) after non-severe burn injury. Trabecular number was significantly decreased (0.57/mm after injury compared to 1.02/mm controls, p=0.0051) and spacing increased after burn injury (0.40 compared to 0.28, p=0.0083). Anti-TNF-α antibodies significantly improved trabecular bone volume (8.53%, p=0.0034) and number after burn injury (1.28/mm, p=0.0034). There was no significant change observed in cortical bone after burn injury or administration of anti-TNF-α antibodies. These findings show that non-severe burn injury can lead to changes in bone metabolism. Monitoring bone density in patients with non-severe injuries and interventions to limit the impacts of the inflammatory storm may benefit patient recovery and outcomes.

Summary Aim Approximately 40-60% of melanomas from Caucasian populations carry activating mutations in the BRAF oncogene, with the most common being the p.Val600Glu (V600E) hotspot mutation in exon 15. The aim of the present study was to investigate the frequency of the less common p.Val600Lys (V600K) mutation in metastatic melanoma from a high incidence region. Method Dideoxy sequencing and fluorescent single strand conformation analysis were used to screen for mutations in exon 15 of BRAF in 183 cases of metastatic melanoma. Results The overall incidence of BRAF mutation (89/183, 49%) was very similar to other large studies of Caucasian populations. However, the frequency of the p.Val600Lys mutation was higher than in most other studies and comprised almost one-third of all BRAF mutations in our cohort (27/89, 30%). Conclusion BRAF p.Val600Lys mutations were present at a relatively high frequency in this cohort of metastatic melanoma patients (27/183, 15%). Assays used to screen for BRAF mutations in the clinic should be robust enough to detect the p.Val600Lys mutation, as this may have therapeutic implications.