Natural Tolerance to Ischemia and Hypoxemia in Diving Mammals: A Review

Reperfusion injury follows ischemia/reperfusion events occurring during myocardial infarction, stroke, embolism, and other peripheral vascular diseases. Decreased blood flow and reduced oxygen tension during ischemic episodes activate cellular pathways that upregulate pro-inflammatory signaling and promote oxidant generation. Reperfusion after ischemia recruits inflammatory cells to the vascular wall, further exacerbating oxidant production and ultimately resulting in cell death, tissue injury, and organ dysfunction. Diving mammals tolerate repetitive episodes of peripheral ischemia/reperfusion as part of the cardiovascular adjustments supporting long duration dives. These adjustments allow marine mammals to optimize the use of their body oxygen stores while diving but can result in selectively reduced perfusion to peripheral tissues. Remarkably, diving mammals show no apparent detrimental effects associated with these ischemia/reperfusion events. Here, we review the current knowledge regarding the strategies marine mammals use to suppress inflammation and cope with oxidant generation potentially derived from diving-induced ischemia/reperfusion.
Source: Frontiers in Physiology - Category: Physiology Source Type: research

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This is by one of ouroutstanding 3rd year residents, Aaron Robinson, with some edits and comments by SmithEMS responded to a reported seizure in a 42 year old male. Per bystanders, he went down after some intense sporting activity, and had “shaking” type movement. He reports no personal or familial history of seizures.One of our EMS Fellows along with a Senior EM Resident were on duty that evening, and arrived on the scene with the Fire Department. When the physicians approached him, he was ashen, diaphoretic, and appeared in shock. Fire was able to obtain a BP of 60/palp and a pulse in the 40s. The physicians ...
Source: Dr. Smith's ECG Blog - Category: Cardiology Authors: Source Type: blogs
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Source: American Journal of Nephrology - Category: Urology & Nephrology Authors: Tags: Am J Nephrol Source Type: research
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Source: American Heart Journal - Category: Cardiology Source Type: research
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Source: Frontiers in Neurology - Category: Neurology Source Type: research
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Source: Frontiers in Physiology - Category: Physiology Source Type: research
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Source: Frontiers in Immunology - Category: Allergy & Immunology Source Type: research
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Source: Frontiers in Endocrinology - Category: Endocrinology Source Type: research
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Source: Dr. Smith's ECG Blog - Category: Cardiology Authors: Source Type: blogs
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Source: American Journal of Therapeutics - Category: Drugs & Pharmacology Tags: Systematic Reviews Source Type: research
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Source: Current Pharmaceutical Design - Category: Drugs & Pharmacology Authors: Tags: Curr Pharm Des Source Type: research
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