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Mesenteric ischemia and reperfusion (I/R) injury can ensue from a variety of vascular diseases and represents a major cause of morbidity and mortality in intensive care units. It causes an inflammatory response associated with local gut dysfunction and remote organ injury. Adenosine monophosphate-activated protein kinase (AMPK) is a crucial regulator of metabolic homeostasis. The catalytic α1 subunit is highly expressed in the intestine and vascular system. In loss-of-function studies, we investigated the biological role of AMPKα1 in affecting the gastrointestinal barrier function. Male knock-out (KO) mice with a systemic deficiency of AMPKα1 and wild-type (WT) mice were subjected to a 30 min occlusion of the superior mesenteric artery. Four hours after reperfusion, AMPKα1 KO mice exhibited exaggerated histological gut injury and impairment of intestinal permeability associated with marked tissue lipid peroxidation and a lower apical expression of the junction proteins occludin and E-cadherin when compared to WT mice. Lung injury with neutrophil sequestration was higher in AMPKα1 KO mice than WT mice and paralleled with higher plasma levels of syndecan-1, a biomarker of endothelial injury. Thus, the data demonstrate that AMPKα1 is an important requisite for epithelial and endothelial integrity and has a protective role in remote organ injury after acute ischemic events.

Storms strongly affect coral reefs; one unstudied but potentially important outcome may be a decrease in herbivory, presumably through changes to freshwater, sediment and nutrient influx. Algal turfs are sensitive early indicators of reef condition, and experimental evidence demonstrates low sediment loads and strong herbivory maintain short, healthy turf. While unknown, storms likely disrupt these controlling forces. We have observed storms that generate frequent, visible sediment plumes in Moorea, French Polynesia. To evaluate the effects of storms on herbivory, we conducted a set of field experiments manipulating herbivore access to naturally occurring turf under three rainfall regimes: no rain, light rain, and heavy rain that generated a plume event. We found strong effects of herbivores except following the storm, indicating disruption of typically strong top-down control by herbivores on algal turfs. Further research into the underlying mechanisms is critical as storm intensities and watershed development increase in many tropical regions., Competing Interests: Conflict of interestOn behalf of all authors, the corresponding author states that there is no conflict of interest., (© The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature 2021.)

Background: Enoxaparin is used as chemoprophylaxis to reduce incidence of venous thromboembolism and its complications following trauma. Serum anti-Xa monitoring is used to assess efficacy but requires several doses to be administered. Thrombelastography assesses hypercoagulability and may have utility identifying high-risk patients for venous thromboembolism. The objective was to evaluate whether thrombelastography parameters could identify trauma patients requiring enoxaparin dose adjustment earlier than serum anti-Xa concentrations., Methods: A single-center, retrospective medical record review evaluated patients admitted to a regional level I trauma center that received an admission thrombelastography and a dose of enoxaparin with a serum trough anti-Xa concentration drawn. Patients were divided into standard-dose or dose-adjusted enoxaparin. Venous thromboembolism incidence between groups and risk factors for enoxaparin dose adjustment and venous thromboembolism development were evaluated., Results: A total of 204 patients were included. Differences observed between groups included age (standard-dose enoxaparin, 48.5 [29.3-72] vs dose-adjusted enoxaparin, 38.5 [25-55.7] years; P  = .005), admission creatinine clearance (standard-dose enoxaparin, 92.9 [67.4-113.4] vs dose-adjusted enoxaparin, 102.1 [83.8-129.2] mL/min; P  = .017), and time to venous thromboembolism prophylaxis initiation (standard-dose enoxaparin, 23.8 [11.2-36.4] vs dose-adjusted enoxaparin, 34.5 [18.3-52.7] hours; P  = .004). No differences in thrombelastography parameters or venous thromboembolism incidence were observed. No independent risk factors for enoxaparin dose adjustment were identified; however, risk assessment profile score > 10 was an independent risk factor for venous thromboembolism development., Conclusion: No relationship between admission thrombelastography and need for enoxaparin dose adjustment in trauma patients was observed. As thrombelastography continues growing in clinical use, it is prudent to investigate other potential applications. Currently, thrombelastography should not be used to guide enoxaparin dosing., (© 2020 The Authors.)