RESUMO
Cefepime is a renally excreted, fourth-generation cephalosporin used in the treatment of severe abdominal, skin, soft tissue, and urinary tract infections due to its broad-spectrum coverage. Cefepime-induced neurotoxicity is a rare but serious side effect that has increased in recent years likely due to increased antibiotic use, increased drug resistance, and increased symptom recognition. While decreased glomerular filtration rate is an important risk factor for developing elevated serum cefepime levels, recent literature has suggested that a significant proportion of patients with normal renal function can also develop neurotoxicity from cefepime. Here, we present a case of cefepime-induced neurotoxicity to demonstrate the importance of monitoring mental status changes in all patients being treated with cefepime.
RESUMO
Large-conductance calcium-activated potassium (BK) channels play a critical role in electrical resonance, a mechanism of frequency selectivity in chicken hair cells. We determine that BK currents are dependent on inward flow of Ca2+ , and intracellular buffering of Ca2+ . Entry of Ca2+ is further amplified locally by calcium-induced Ca2+ release (CICR) in close proximity to plasma membrane BK channels. Ca2+ imaging reveals peripheral clusters of high concentrations of Ca2+ that are suprathreshold to that needed to activate BK channels. Protein kinase A (PKA) activation increases the size of BK currents likely by recruiting more BK channels due to spatial spread of high Ca2+ concentrations in turn from increasing CICR. STORM imaging confirms the presence of nanodomains with ryanodine and IP3 receptors in close proximity to the Slo subunit of BK channels. Together, these data require a rethinking of how electrical resonance is brought about and suggest effects of CICR in synaptic release. Both genders were included in this study.