Dietary modulation of the effects of sevoflurane on myocardial perfusion, function and ischemic injury in rats

Loer, S.A. [Promotor]Boer, C. [Copromotor]Bouwman, R.A. [Copromotor

Sex differences and loss of Tie2

Abstract The endothelial angiopoietin/Tie2 system is an important regulator of endothelial permeability and targeting Tie2 reduces hemorrhagic shock-induced organ edema in males. However, sexual dimorphism of the endothelium has not been taken into account. This study investigated whether there are sex-related differences in the endothelial angiopoietin/Tie2 system and edema formation. Adult male and female heterozygous Tie2 knockout mice (Tie2+/−) and wild-type controls (Tie2+/+) were included (n=9 per group). Renal and pulmonary injury were determined by wet/dry weight ratio and H&E staining of tissue sections. Protein levels were studied in plasma by ELISA and pulmonary and renal mRNA expression levels by RT-qPCR. In Tie2+/+ mice, females had higher circulating angiopoietin-2 (138%, p<0.05) compared to males. Gene expression of angiopoietin-1 (204%, p<0.01), angiopoietin-2 (542%, p<0.001) were higher in females compared to males in kidneys, but not in lungs. Gene expression of Tie2, Tie1 and VE-PTP were similar between males and females in kidneys and lungs. Renal and pulmonary wet/dry weight ratio did not differ between Tie2+/+ females and males. Tie2+/+ females had lower circulating NGAL (41%, p<0.01) compared to males, whereas renal NGAL and KIM1 gene expression was unaffected. Interestingly, male Tie2+/- mice had 28% higher renal wet/dry weight ratio (p<0.05) compared to Tie2+/+ males, which was not observed in females nor in lungs. Partial deletion of Tie2 did not affect circulating angiopoietin-1 or angiopoietin-2, but soluble Tie2 was 44% and 53% lower in males and females, respectively, compared to Tie2+/+ mice of the same sex. Renal and pulmonary gene expression of angiopoietin-1, angiopoietin-2, estrogen receptors and other endothelial barrier regulators was comparable between Tie2+/- and Tie2+/+ mice in both sexes. Female sex seems to protect against renal, but not pulmonary edema in heterozygous Tie2 knock-out mice. This could not be explained by sex dimorphism in the endothelial angiopoietin/Tie2 system

Knowledge gaps and research priorities in adult veno-arterial extracorporeal membrane oxygenation: a scoping review

Purpose: This scoping review aims to identify and describe knowledge gaps and research priorities in veno-arterial extracorporeal membrane oxygenation (VA-ECMO). Methods: An expert panel was recruited consisting of eight international experts from different backgrounds. First, a list of priority topics was made. Second, the panel developed structured questions using population, intervention, comparison and outcomes (PICO) format. All PICOs were scored and prioritized. For every selected PICO, a structured literature search was performed. Results: After an initial list of 49 topics, eight were scored as high-priority. For most of these selected topics, current literature is limited to observational studies, mainly consisting of retrospective cohorts. Only for ECPR and anticoagulation, randomized controlled trials (RCTs) have been performed or are ongoing. Per topic, a summary of the literature is stated including recommendations for further research. Conclusions: This scoping review identifies and presents an overview of knowledge gaps and research priorities in VA-ECMO. Current literature is mostly limited to observational studies, although with increasing attention for this patient population, more RCTs are finishing or ongoing. Translational research, from preclinical trials to high-quality or randomized controlled trials, is important to improve the standard practices in this critically ill patient population. Take-home message This scoping review identifies and presents an overview of research gaps and priorities in VA-ECMO. Translational research, from preclinical trials to high-quality or randomized controlled trials, is important to improve the standard practices in this critically ill patient population.SCOPUS: re.jinfo:eu-repo/semantics/publishe

Diaphragm muscle fiber weakness and ubiquitin-proteasome activation in critically ill patients

Contains fulltext : 155008.pdf (publisher's version ) (Closed access)RATIONALE: The clinical significance of diaphragm weakness in critically ill patients is evident: it prolongs ventilator dependency, and increases morbidity and duration of hospital stay. To date, the nature of diaphragm weakness and its underlying pathophysiologic mechanisms are poorly understood. OBJECTIVES: We hypothesized that diaphragm muscle fibers of mechanically ventilated critically ill patients display atrophy and contractile weakness, and that the ubiquitin-proteasome pathway is activated in the diaphragm. METHODS: We obtained diaphragm muscle biopsies from 22 critically ill patients who received mechanical ventilation before surgery and compared these with biopsies obtained from patients during thoracic surgery for resection of a suspected early lung malignancy (control subjects). In a proof-of-concept study in a muscle-specific ring finger protein-1 (MuRF-1) knockout mouse model, we evaluated the role of the ubiquitin-proteasome pathway in the development of contractile weakness during mechanical ventilation. MEASUREMENTS AND MAIN RESULTS: Both slow- and fast-twitch diaphragm muscle fibers of critically ill patients had approximately 25% smaller cross-sectional area, and had contractile force reduced by half or more. Markers of the ubiquitin-proteasome pathway were significantly up-regulated in the diaphragm of critically ill patients. Finally, MuRF-1 knockout mice were protected against the development of diaphragm contractile weakness during mechanical ventilation. CONCLUSIONS: These findings show that diaphragm muscle fibers of critically ill patients display atrophy and severe contractile weakness, and in the diaphragm of critically ill patients the ubiquitin-proteasome pathway is activated. This study provides rationale for the development of treatment strategies that target the contractility of diaphragm fibers to facilitate weaning

Saccular Abdominal Aortic Aneurysms Patient Characteristics, Clinical Presentation, Treatment, and Outcomes in the Netherlands

Objective: The aim of this was to analyze differences between saccularshaped abdominal aortic aneurysms (SaAAAs) and fusiform abdominal aortic aneurysms (FuAAAs) regarding patient characteristics, treatment, and outcome, to advise a threshold for intervention for SaAAAs.Background: Based on the assumption that SaAAAs are more prone to rupture, guidelines suggest early elective treatment. However, little is known about the natural history of SaAAAs and the threshold for intervention is not substantiated.Methods: Observational study including primary repairs of degenerative AAAs in the Netherlands between 2016 and 2018 in which the shape was registered, registered in the Dutch Surgical Aneurysm Audit (DSAA). Patients were stratified by urgency of surgery; elective versus acute (symptomatic/ruptured). Patient characteristics, treatment, and outcome were compared between SaAAAs and FuAAAs.Results: A total of 7659 primary AAA-patients were included, 6.1% (n = 471) SaAAAs and 93.9% (n = 7188) FuAAAs. There were 5945 elective patients (6.5% SaAAA) and 1714 acute (4.8% SaAAA). Acute SaAAApatients were more often female (28.9% vs 17.2%, P = 0.007) compared with acute FuAAA-patients. SaAAAs had smaller diameters than FuAAAs, in elective (53.0mm vs 61 mm, P = 0.000) and acute (68mm vs 75 mm, P = 0.002) patients, even after adjusting for sex. In addition, 25.2% of acute SaAAA-patients presented with diameters <55mm and 8.4% <45 mm, versus 8.1% and 0.6% of acute FuAAA-patients (P = 0.000). Postoperative outcomes did not significantly differ between shapes in both elective and acute patients.Conclusions: SaAAAs become acute at smaller diameters than FuAAAs in DSAA patients. This study therefore supports the current idea that SaAAAs should be electively treated at smaller diameters than FuAAAs. The exact diameter threshold for elective treatment of SaAAAs is difficult to determine, but a diameter of 45mm seems to be an acceptable threshold.Vascular Surger