Search

Introduction Hepatitis B virus (HBV) infection remains a global public health threat, with approximately 257 million people suffering from chronic HBV infection worldwide in 2015. HBV reactivation is a known complication of immunosuppressive therapy in people suffering with chronic HBV. Medications commonly associated with HBV reactivation include B-cell depleting agents and anthracycline derivatives. There have been very few documented cases of chemoradiation inducing HBV reactivation among scientific literature. Case report A 44-year-old woman with chronic HBV infection and [FIGO] stage IIIB cervical cancer developed marked transaminitis and increased HBV viral load after receiving treatment with three doses of cisplatin and one dose of carboplatin with concurrent radiation for cervical cancer. Management and outcome: The patient was admitted for acute liver failure and quickly developed encephalopathy, with treatment complicated by coagulopathy, hypoglycemia, and metabolic acidosis. The patient remained unresponsive to maximal therapeutic efforts and was mechanically ventilated for airway protection. She subsequently died after experiencing ventricular tachycardia followed by asystole. Discussion There are currently no standardized guidelines for the screening of HBV infection or prophylaxis treatment algorithm for patients undergoing chemoradiation. When initiating treatment with immunosuppressive therapy, it is important to screen all patients for chronic HBV infection and to work with an interdisciplinary team of oncologists, hepatologists, and pharmacists to initiate prophylactic antiviral therapy and closely monitor to minimize the risk of HBV reactivation.

Habituation of a behavioral response to a repetitive stimulus enables animals to ignore irrelevant stimuli and focus on behaviorally important events. In Aplysia, habituation is mediated by rapid depression of sensory synapses, which could leave an animal unresponsive to important repetitive stimuli, making it vulnerable to injury. We identified a form of plasticity that prevents synaptic depression depending on the precise stimulus strength. Burst-dependent protection from depression is initiated by trains of 2–4 action potentials, and is distinct from previously described forms of synaptic enhancement. The blockade of depression is mediated by presynaptic Ca2+ influx and protein kinase C (PKC), and requires localization of PKC via a PDZ domain interaction with Aplysia PICK1. During protection from depression, PKC acts as a highly sensitive detector of the precise pattern of sensory neuron firing. Behaviorally, burst-dependent protection reduces habituation, enabling animals to maintain responsiveness to stimuli that are functionally important.