Angiotensin II (Ang II)-mediated activation of its type I receptor (AT1R) in the central nervous system promotes glial proliferation, local inflammation, and a decrease of cerebral blood flow. Angiotensin-(1-7) (Ang-(1-7))-an Ang II derivative peptide-signals through the Mas receptor (MasR) in opposition to Ang II/AT1R, promoting anti-inflammatory, vasodilatory, and neuroprotective effects. As our laboratory has previously demonstrated beneficial effects of AT1R inhibition following controlled cortical impact (CCI) in mice, we asked whether activation of Ang-(1-7)/MasR signaling would also be beneficial in this model. Adult male C57BL/6 mice were injured by CCI. Ang-(1-7) or vehicle was administered subcutaneously (S.Q.) at 1 mg/kg/day at 1 or 6 h post-injury, until animals were sacrificed at 3 or 29 days post-injury (dpi). Ang-(1-7) attenuated motor deficits at 3 dpi and improved performance in the Morris Water Maze at 28 dpi. Brain histology or magnetic resonance imaging (MRI) indicated that Ang-(1-7)-treated mice had smaller lesion volumes at 3, 10, 24, and 29 dpi. Pre-treatment with A779, a MasR antagonist, prevented Ang-(1-7) from reducing lesion volume at 3 dpi, suggesting that the benefits of Ang-(1-7) were MasR-dependent. Immunohistochemistry revealed that Ang-(1-7) reduced microgliosis at 3 and 29 dpi, and astrogliosis at 29 dpi. Ang-(1-7) decreased neuronal and capillary loss at 29 dpi. In summary, S.Q. administration of Ang-(1-7) after injury had anti-inflammatory, neuroprotective, and cerebrovascularprotective actions leading to improved functional and pathological recovery in a mouse model of traumatic brain injury (TBI). These data show for the first time that Ang-(1-7) has potential therapeutic use for TBI.

During disasters, the roles of physicians, nurses, and ancillary medical staff are defined by their individual certifications, whereas the roles of medical students remain less clear. Medical students are unlicensed physicians-in-training, with variable degrees of skill and knowledge, and thus, their involvement in disaster response has historically varied. In light of the coronavirus disease 2019 pandemic, many junior students were asked to remove themselves from the hospital setting, whereas some senior students graduated early to join the physician workforce. In this article, the authors will examine the psychosocial benefits and consequences of medical student involvement in prior disasters and developing attitudes in light of the coronavirus disease 2019 pandemic. We conclude by offering our thoughts on medical student involvement in future disasters.

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Traumatic brain injury has been called the “signature injury” of the wars in Iraq and Afghanistan, and the management of severe and penetrating brain injury has evolved considerably based on the experiences of military neurosurgeons. Current guidelines recommend that decompressive hemicraniectomy be performed with large, frontotemporoparietal bone flaps, but practice patterns vary markedly. The following case is illustrative of potential clinical courses, complications, and efforts to salvage inadequately-sized decompressive craniectomies performed for combat-related severe and penetrating brain injury. The authors follow this with a review of the current literature pertaining to decompressive craniectomy, and finally provide their recommendations for some of the technical nuances of performing decompressive hemicraniectomy after severe or penetrating brain injury.

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