Harmful algal blooms in the Gulf of Mexico : brevetoxin degradation and derivation formation via photochemical processes

Harmful algal blooms (HAB’s) of the dinoflagellate Karenia brevis (Gymnodinium breve) are recurring events in the Gulf of Mexico (GOM) which have significant adverse human health, environmental and economic impacts. Brevetoxins (PbTx), produced by K. brevis, are potent neurotoxins and during HAB events are responsible for mass morbidity and mortality in fish, birds and marine mammals and the causative agent(s) of Neurotoxic Shellfish Poisoning (NSP) in humans. Brevetoxin exposure (inhalation or oral) results in systemic distribution of the toxin to all bodily tissues with a variety pathophysiological sequelae. Current evidence suggests that, in addition to the known acute toxicological effects on cardiovascular, neuromuscular, and respiratory systems, chronic brevetoxin exposure may result in immunosuppression and toxicity to the hemopoietic and thermoregulatory systems. Brevetoxin (PbTx1) has recently been shown to be teratogenic in fish embryo studies. While acute effects of brevetoxin exposures have been studied over the last two decades, far less is known about the effects of chronic/repeated brevetoxin exposure on humans and marine wildlife and little is understood about the transport and fate of brevetoxins in the environment (water, air, sediments, and selected biota). In order to apply effective risk assessment and develop accurate and reliable detection methodologies, greater knowledge of the transport and fate of brevetoxins in the environment are needed. These findings suggest solar radiation plays a significant role in the mediation of brevetoxin (PbTx2) degradation and brevetoxin derivative formation. Hence, it suggested that photochemistry may play a critical role in the transport and fate of brevetoxin(s) in the environment

Extrahepatic Portal Vein Aneurysm

AbstractPortal vein aneurysms are rare vascular abnormalities, many of which are incidentally discovered on routine imaging studies. The etiology of portal venous aneurysms is poorly understood, and the management of these lesions is debatable. We report the case of a 61-year-old woman with extrahepatic portal vein aneurysm. We review the nature and significance of this abnormality and discuss appropriate clinical, imaging, and treatment approaches