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Background and Purpose Subarachnoid hemorrhage (SAH) can leave patients with memory impairments that may not recover fully. Molecular mechanisms are poorly understood, and no treatment is available. The sulfonylurea receptor 1–transient receptor potential melastatin 4 (Sur1-Trpm4) channel plays an important role in acute central nervous system injury. We evaluated upregulation of Sur1-Trpm4 in humans with SAH and, in rat models of SAH, we examined Sur1- Trpm4 upregulation, its role in barrier dysfunction and neuroinflammation, and its consequences on spatial learning. Methods We used Förster resonance energy transfer to detect coassociated Sur1 and Trpm4 in human autopsy brains with SAH. We studied rat models of SAH involving filament puncture of the internal carotid artery or injection of blood into the subarachnoid space of the entorhinal cortex. In rats, we used Förster resonance energy transfer and coimmunoprecipitation to detect coassociated Sur1 and Trpm4, we measured immunoglobulin G extravasation and tumor necrosis α overexpression as measures of barrier dysfunction and neuroinflammation, and we assessed spatial learning and memory on days 7 to 19. Results Sur1-Trpm4 channels were upregulated in humans and rats with SAH. In rats, inhibiting Sur1 using antisense or the selective Sur1 inhibitor glibenclamide reduced SAH-induced immunoglobulin G extravasation and tumor necrosis α overexpression. In models with entorhinal SAH, rats treated with glibenclamide for 7 days after SAH exhibited better platform search strategies and better performance on incremental and rapid spatial learning than vehicle-treated controls. Conclusions Sur1-Trpm4 channels are upregulated in humans and rats with SAH. Channel inhibition with glibenclamide may reduce neuroinflammation and the severity of cognitive deficits after SAH.

Postmortem fingerprint collection is a routine part of many forensic death investigations. Although the production of postmortem prints is usually straight forward, several obstacles and scenarios can make the collection difficult. A common challenge occurs when finger pads are mummified. Several current techniques allow for softening and rehydration of mummified finger pads; however, despite the employment of such techniques, the production of adequate postmortem fingerprints can remain elusive. The authors present two techniques that can improve the chances of obtaining suitable fingerprints from mummified remains. The "baby powder method" involves applying a cornstarch-based powder, such as baby powder, onto the darkened and mummified finger pads, to allow better visualization of the fingerprint detail. The "transillumination method" involves carefully dissecting away the tissues underlying the finger pad, followed by placement of a bright light source underneath the finger pad, such that the finger ridge pattern is illuminated.