Assessment of patients with a suspected cardioembolic ischemic stroke. A national consensus statement.

OBJECTIVES: Several cardiovascular, structural, and functional abnormalities have been considered as potential causes of cardioembolic ischemic strokes. Beyond atrial fibrillation, other sources of embolism clearly exist and may warrant urgent action, but they are only a minor part of the many stroke mechanisms and strokes that seem to be of embolic origin remain without a determined source. The associations between stroke and findings like atrial fibrillation, valve calcification, or heart failure are confounded by co-existing risk factors for atherosclerosis and vascular disease. In addition, a patent foramen ovale which is a common abnormality in the general population is mostly an innocent bystander in patients with ischemic stroke. For these reasons, experts from the national Danish societies of cardiology, neurology, stroke, and neuroradiology sought to develop a consensus document to provide national recommendations on how to manage patients with a suspected cardioembolic stroke. Design: Comprehensive literature search and analyses were done by a panel of experts and presented at a consensus meeting. Evidence supporting each subject was vetted by open discussion and statements were adjusted thereafter. Results: The most common sources of embolic stroke were identified, and the statement provides advise on how neurologist can identify cases that need referral, and what is expected by the cardiologist. Conclusions: A primary neurological and neuroradiological assessment is mandatory and neurovascular specialists should manage the initiation of secondary prophylactic treatment. If a cardioembolic stroke is suspected, a dedicated cardiologist experienced in the management of cardioembolism should provide a tailored clinical and echocardiographic assessment.

Effect of remote ischaemic conditioning on clinical outcomes in patients with acute myocardial infarction (CONDI-2/ERIC-PPCI): a single-blind randomised controlled trial.

BACKGROUND: Remote ischaemic conditioning with transient ischaemia and reperfusion applied to the arm has been shown to reduce myocardial infarct size in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). We investigated whether remote ischaemic conditioning could reduce the incidence of cardiac death and hospitalisation for heart failure at 12 months. METHODS: We did an international investigator-initiated, prospective, single-blind, randomised controlled trial (CONDI-2/ERIC-PPCI) at 33 centres across the UK, Denmark, Spain, and Serbia. Patients (age >18 years) with suspected STEMI and who were eligible for PPCI were randomly allocated (1:1, stratified by centre with a permuted block method) to receive standard treatment (including a sham simulated remote ischaemic conditioning intervention at UK sites only) or remote ischaemic conditioning treatment (intermittent ischaemia and reperfusion applied to the arm through four cycles of 5-min inflation and 5-min deflation of an automated cuff device) before PPCI. Investigators responsible for data collection and outcome assessment were masked to treatment allocation. The primary combined endpoint was cardiac death or hospitalisation for heart failure at 12 months in the intention-to-treat population. This trial is registered with ClinicalTrials.gov (NCT02342522) and is completed. FINDINGS: Between Nov 6, 2013, and March 31, 2018, 5401 patients were randomly allocated to either the control group (n=2701) or the remote ischaemic conditioning group (n=2700). After exclusion of patients upon hospital arrival or loss to follow-up, 2569 patients in the control group and 2546 in the intervention group were included in the intention-to-treat analysis. At 12 months post-PPCI, the Kaplan-Meier-estimated frequencies of cardiac death or hospitalisation for heart failure (the primary endpoint) were 220 (8·6%) patients in the control group and 239 (9·4%) in the remote ischaemic conditioning group (hazard ratio 1·10 [95% CI 0·91-1·32], p=0·32 for intervention versus control). No important unexpected adverse events or side effects of remote ischaemic conditioning were observed. INTERPRETATION: Remote ischaemic conditioning does not improve clinical outcomes (cardiac death or hospitalisation for heart failure) at 12 months in patients with STEMI undergoing PPCI. FUNDING: British Heart Foundation, University College London Hospitals/University College London Biomedical Research Centre, Danish Innovation Foundation, Novo Nordisk Foundation, TrygFonden.

Urinary Neutrophil Gelatinase-associated Lipocalin in the evaluation of Patent Ductus Arteriosus and AKI in Very Preterm Neonates: a cohort study.

BACKGROUND: A patent ductus arteriosus (PDA) is frequently found in very preterm neonates and is associated with increased risk of morbidity and mortality. A shunt across a PDA can result in an unfavorable distribution of the cardiac output and may in turn result in poor renal perfusion. Urinary Neutrophil Gelatinase-associated Lipocalin (U-NGAL) is a marker of renal ischemia and may add to the evaluation of PDA. Our primary aim was to investigate if U-NGAL is associated with PDA in very preterm neonates. Secondary, to investigate whether U-NGAL and PDA are associated with AKI and renal dysfunction evaluated by fractional excretion of sodium (FENa) and urine albumin in a cohort of very preterm neonates. METHODS: A cohort of 146 neonates born at a gestational age less than 32 weeks were consecutively examined with echocardiography for PDA and serum sodium, and urine albumin and sodium were measured on postnatal day 3 and U-NGAL and serum creatinine day 3 and 6. AKI was defined according to modified neonatal Acute Kidney Injury Network (AKIN) criteria. The association between U-NGAL and PDA was investigated. And secondly we investigated if PDA and U-NGAL was associated with AKI and renal dysfunction. RESULTS: U-NGAL was not associated with a PDA day 3 when adjusted for gestational age and gender. A PDA day 3 was not associated with AKI when adjusted for gestational age and gender; however, it was associated with urine albumin. U-NGAL was not associated with AKI, but was found to be associated with urine albumin and FENa. CONCLUSIONS: Based on our study U-NGAL is not considered useful as a diagnostic marker to identify very preterm neonates with a PDA causing hemodynamic changes resulting in early renal morbidity. The interpretation of NGAL in preterm neonates remains to be fully elucidated.

Rotigaptide protects the myocardium and arterial vasculature from ischaemia reperfusion injury.

AIM: Ischaemia-reperfusion injury (IRI) causes impaired endothelial function and is a major component of the adverse effects of reperfusion following myocardial infarction. Rotigaptide increases gap junction conductance via connexin-43. We tested the hypothesis that rotigaptide reduces experimental myocardial infarction size and ameliorates endothelial IRI in humans. METHODS: Myocardial infarction study: porcine myocardial infarction was achieved by catheter-induced occlusion of the left anterior descending artery. In a randomized double-blind study, rotigaptide (n = 9) or placebo (n = 10) was administered intravenously as a 10 min bolus prior to reperfusion and continuously during 2 h of reperfusion. Myocardial infarction size (IS) was assessed as proportion of the area at risk (AAR). Human translational study: forearm IRI was induced in the presence or absence of intra-arterial rotigaptide. In a randomized double-blind study, forearm arterial blood flow was measured at rest and during intra-arterial infusion of acetylcholine (5-20 µg min(-1) ; n = 11) or sodium nitroprusside (2-8 mg min(-1) ; n = 10) before and after intra-arterial infusion of placebo or rotigaptide, and again following IRI. RESULTS: Myocardial infarction study: Rotigaptide treatment was associated with a reduction of infarct size (IS/AAR[%]: 18.7 ± 4.1 [rotigaptide] vs. 43.6 ± 4.2 [placebo], P = 0.006). Human translational study: Endothelium-dependent vasodilatation to acetylcholine was attenuated after ischaemia-reperfusion in the presence of placebo (P = 0.007), but not in the presence of rotigaptide (P = NS). Endothelium-independent vasodilatation evoked by sodium nitroprusside was unaffected by IRI or rotigaptide (P = NS). CONCLUSIONS: Rotigaptide reduces myocardial infarction size in a porcine model and protects from IRI-related endothelial dysfunction in man. Rotigaptide may have therapeutic potential in the treatment of myocardial infarction.

Gadkin negatively regulates cell spreading and motility via sequestration of the actin-nucleating ARP2/3 complex.

Regulation of actin dynamics is key to many cell physiological processes, ranging from protrusion formation and control of cell shape to cellular motility, endocytosis, and vesicle movement. The actin-related protein (ARP)2/3 complex is a major actin nucleator organizing branched filament networks in lamellipodial protrusions and during cell migration downstream of nucleation-promoting factors (NPFs). Although many NPFs have been characterized in detail, only few ARP2/3 inhibitors are known. Here, we identify the trans-Golgi network (TGN)/endosomally localized adaptor protein (AP)-1-associated adaptor protein Gadkin as a negative regulator of ARP2/3 function. Loss of Gadkin is associated with a partial redistribution of ARP2/3 to the plasma membrane and with increased cell spreading and migration, phenotypes that depend on the presence of a functional ARP2/3 complex. Gadkin directly binds to ARP2/3 via a conserved tryptophan-based acidic cluster motif reminiscent of ARP2/3-binding sequences of NPFs but fails to facilitate ARP2/3-mediated actin assembly. Consistent with an inhibitory role of Gadkin on ARP2/3 function, ARP2/3 is found on motile Gadkin-containing endosomal vesicles under migration-inhibiting conditions from where it relocalizes to the plasma membrane following activation of NPFs. Together with the observation that Gadkin-mediated inhibition of cell spreading requires its binding to ARP2/3, these data indicate that Gadkin is a negative regulator of ARP2/3 function present on intracellular membranes.

Improved long-term clinical outcomes in patients with ST-elevation myocardial infarction undergoing remote ischaemic conditioning as an adjunct to primary percutaneous coronary intervention.

AIMS: Remote ischaemic conditioning as an adjunct to primary percutaneous coronary intervention in patients with ST-elevation myocardial infarction increases myocardial salvage. We investigated the effect of remote ischaemic conditioning on long-term clinical outcome. METHODS AND RESULTS: From February 2007 to November 2008, 333 patients with a suspected first acute ST-elevation myocardial infarction were randomized to receive primary percutaneous coronary intervention with (n = 166) or without (n = 167) remote ischaemic conditioning (intermittent arm ischaemia through four cycles of 5-min inflation followed by 5-min deflation of a blood-pressure cuff). Patient follow-up extended from the randomization date until an outcome, emigration or January 2012 (median follow-up = 3.8 years). The primary endpoint was major adverse cardiac and cerebrovascular events (MACCE)-a composite of all-cause mortality, myocardial infarction, readmission for heart failure, and ischaemic stroke/transient ischaemic attack. The individual components of the primary endpoint comprised the secondary endpoints. Outcomes were obtained from Danish nationwide medical registries and validated by medical record review and contact to patients' general practitioner. In the per-protocol analysis of 251 patient fulfilling trial criteria, MACCE occurred for 17 (13.5%) patients in the intervention group compared with 32 (25.6%) patients in the control group, yielding a hazard ratio (HR) of 0.49 (95% confidence interval: 0.27-0.89, P = 0.018). The HR for all-cause mortality was 0.32 (95% confidence interval: 0.12-0.88, P = 0.027). Although lower precision, the HRs were also directionally lower for all other secondary endpoints. CONCLUSION: Remote ischaemic conditioning before primary percutaneous coronary intervention seemed to improve long-term clinical outcomes in patients with ST-elevation myocardial infarction.

Inotropic therapy for right ventricular failure in newborn piglets: effect on contractility, hemodynamics, and interventricular interaction.

OBJECTIVES: To investigate the effect of right ventricular stunning on interventricular relationships in newborn piglets and to determine the effect of three commonly used inotropic treatment strategies. DESIGN: Randomized, placebo-controlled animal study. SETTING: Aarhus University Hospital, animal laboratory. SUBJECTS: Twenty-eight newborn (4-d old) farm-bred piglets. INTERVENTIONS: Acute right ventricular failure was induced by 10 cycles of alternating 3 minutes of ischemia and reperfusion of the right coronary artery. After right ventricular failure was induced, treatment with epinephrine + milrinone, dopamine + milrinone, dobutamine, or control (saline) was initiated, and the animals were observed for 180 minutes. MEASUREMENTS AND MAIN RESULTS: Right and left ventricular systolic and diastolic variables were measured using pressure-volume loops recorded by conductance catheters. Arterial and central venous pressures were recorded, and cardiac index was determined by placing a flow probe around the pulmonary artery. Whole-body perfusion was evaluated by measuring pH and lactate in arterial blood samples. Induction of right ventricular stunning resulted in decreased ejection fraction (51% ± 4% vs 40% ± 12%, p = 0.0004); caused an interventricular septum deviation, decreased mean arterial pressure (49 ± 10 mm Hg vs 43 ± 11 mm Hg, p = 0.03), and increased blood lactate (1.85 ± 0.6 mM vs 5.79 ± 3.16 mM, p < 0.00001); and led to a decrease in blood pH (7.37 ± 0.08 vs 7.23 ± 0.13, p < 0.00001). A mortality rate greater than 50% was observed in the control group. All inotropic interventions increased contractility significantly in both the left and right ventricle. The effect of dobutamine on right ventricular failure decreased after 30 minutes and was indistinguishable from the control group after 3 hours. Dobutamine-treated animals had lower perfusion pressures and blood pH compared with epinephrine + milrinone and dopamine + milrinone groups. CONCLUSIONS: In newborn piglets, dobutamine had a nonsustained effect on right ventricular failure, resulting in decreased contractility and impaired perfusion compared with both dopamine and epinephrine administered in combination with milrinone.

Aldehyde dehydrogenase-2 inhibition blocks remote preconditioning in experimental and human models.

Mitochondrial aldehyde dehydrogenase-2 (ALDH-2) is involved in preconditioning pathways, but its role in remote ischaemic preconditioning (rIPC) is unknown. We investigated its role in animal and human models of rIPC. (i) In a rabbit model of myocardial infarction, rIPC alone reduced infarct size [69 ± 5.8 % (n = 11) to 40 ± 6.5 % (n = 12), P = 0.019]. However, rIPC protection was lost after pre-treatment with the ALDH-2 inhibitor cyanamide (62 ± 7.6 % controls, n = 10, versus 61 ± 6.9 % rIPC after cyanamide, n = 10, P > 0.05). (ii) In a forearm plethysmography model of endothelial ischaemia-reperfusion injury, 24 individuals of Asian ethnic origin underwent combined rIPC and ischaemia-reperfusion (IR). 11 had wild-type (WT) enzyme and 13 carried the Glu504Lys (ALDH2*2) polymorphism (rendering ALDH-2 functionally inactive). In WT individuals, rIPC protected against impairment of response to acetylcholine (P = 0.9), but rIPC failed to protect carriers of Glu504Lys polymorphism (P = 0.004). (iii) In a second model of endothelial IR injury, 12 individuals participated in a double-blind placebo-controlled crossover study, receiving the ALDH-2 inhibitor disulfiram 600 mg od or placebo for 48 h prior to assessment of flow-mediated dilation (FMD) before and after combined rIPC and IR. With placebo, rIPC was effective with no difference in FMD before and after IR (6.18 ± 1.03 % and 4.76 ± 0.93 % P = 0.1), but disulfiram inhibited rIPC with a reduction in FMD after IR (7.87 ± 1.27 % and 3.05 ± 0.53 %, P = 0.001). This study demonstrates that ALDH-2 is involved in the rIPC pathway in three distinct rabbit and human models. This has potential implications for future clinical studies of remote conditioning.

Small-molecule conversion of toxic oligomers to nontoxic ß-sheet-rich amyloid fibrils.

Several lines of evidence indicate that prefibrillar assemblies of amyloid-ß (Aß) polypeptides, such as soluble oligomers or protofibrils, rather than mature, end-stage amyloid fibrils cause neuronal dysfunction and memory impairment in Alzheimer's disease. These findings suggest that reducing the prevalence of transient intermediates by small molecule-mediated stimulation of amyloid polymerization might decrease toxicity. Here we demonstrate the acceleration of Aß fibrillogenesis through the action of the orcein-related small molecule O4, which directly binds to hydrophobic amino acid residues in Aß peptides and stabilizes the self-assembly of seeding-competent, ß-sheet-rich protofibrils and fibrils. Notably, the O4-mediated acceleration of amyloid fibril formation efficiently decreases the concentration of small, toxic Aß oligomers in complex, heterogeneous aggregation reactions. In addition, O4 treatment suppresses inhibition of long-term potentiation by Aß oligomers in hippocampal brain slices. These results support the hypothesis that small, diffusible prefibrillar amyloid species rather than mature fibrillar aggregates are toxic for mammalian cells.

Ischaemia-reperfusion injury impairs tissue plasminogen activator release in man.

AIMS: Ischaemia-reperfusion (IR) injury causes endothelium-dependent vasomotor dysfunction that can be prevented by ischaemic preconditioning. The effects of IR injury and preconditioning on endothelium-dependent tissue plasminogen activator (t-PA) release, an important mediator of endogenous fibrinolysis, remain unknown. METHODS AND RESULTS: Ischaemia-reperfusion injury (limb occlusion at 200 mmHg for 20 min) was induced in 22 healthy subjects. In 12 subjects, IR injury was preceded by local or remote ischaemic preconditioning (three 5 min episodes of ipsilateral or contralateral limb occlusion, respectively) or sham in a randomized, cross-over trial. Forearm blood flow (FBF) and endothelial t-PA release were assessed using venous occlusion plethysmography and venous blood sampling during intra-arterial infusion of acetylcholine (5-20 µg/min) or substance P (2-8 pmol/min). Acetylcholine and substance P caused dose-dependent increases in FBF (P<0.05 for all). Substance P caused a dose-dependent increase in t-PA release (P<0.05 for all). Acetylcholine and substanceP-mediated vasodilatation and substanceP-mediated t-PA release were impaired following IR injury (P<0.05 for all). Neither local nor remote ischaemic preconditioning protected against the impairment of substance P-mediated vasodilatation or t-PA release. CONCLUSION: Ischaemia-reperfusion injury induced substanceP-mediated, endothelium-dependent vasomotor and fibrinolytic dysfunction in man that could not be prevented by ischaemic preconditioning. CLINICAL TRIAL REGISTRATION INFORMATION: Reference number: NCT00789243, URL: http://clinicaltrials.gov/ct2/show/NCT00789243?term=NCT00789243&rank=1.

Regulation of endosomal membrane traffic by a Gadkin/AP-1/kinesin KIF5 complex.

Endosomes and endosomal vesicles (EVs) rapidly move along cytoskeletal filaments allowing them to exchange proteins and lipids between different endosomal compartments, lysosomes, the trans-Golgi network (TGN), and the plasma membrane. The precise mechanisms that connect membrane traffic between the TGN and perinuclear endosomal compartments with motor-protein driven transport have largely remained elusive. Here we show that Gadkin (also termed gamma-BAR), a peripheral membrane protein localized to the TGN and to TGN-derived EVs, directly associates with the clathrin adaptor AP-1 and with the motor protein kinesin KIF5, thereby potentially regulating EV dynamics. Gadkin overexpression induced the dispersion of transferrin (Tf)- and Rab4-positive EVs to the cell periphery, whereas KIF5B-depleted cells displayed a perinuclear concentration. Functional experiments suggest that the role of Gadkin as a regulator of endosomal membrane traffic critically depends on complex formation with both AP-1 and KIF5. Our data thus provide a direct molecular link between TGN-derived EVs and the microtubule-based cytoskeleton.

A novel subtype of AP-1-binding motif within the palmitoylated trans-Golgi network/endosomal accessory protein Gadkin/gamma-BAR.

Membrane traffic between the trans-Golgi network (TGN) and endosomes is mediated in part by the assembly of clathrin-AP-1 adaptor complex-coated vesicles. This process involves multiple accessory proteins that directly bind to the ear domain of AP-1gamma via degenerate peptide motifs that conform to the consensus sequence diameterG(P/D/E)(diameter/L/M) (with diameter being a large hydrophobic amino acid). Recently, gamma-BAR (hereafter referred to as Gadkin for reasons explained below) has been identified as a novel AP-1 recruitment factor involved in AP-1-dependent endosomal trafficking of lysosomal enzymes. How precisely Gadkin interacts with membranes and with AP-1gamma has remained unclear. Here we show that Gadkin is an S-palmitoylated peripheral membrane protein that lacks stable tertiary structure. S-Palmitoylation is required for the recruitment of Gadkin to TGN/endosomal membranes but not for binding to AP-1. Furthermore, we identify a novel subtype of AP-1-binding motif within Gadkin that specifically associates with the gamma1-adaptin ear domain. Mutational inactivation of this novel type of motif, either alone or in combination with three more conventional AP-1gamma binding peptides, causes Gadkin to mislocalize to the plasma membrane and interferes with its ability to render AP-1 brefeldin A-resistant, indicating its physiological importance. Our studies thus unravel the molecular basis for Gadkin-mediated AP-1 recruitment to TGN/endosomal membranes and identify a novel subtype of the AP-1-binding motif.

Remote ischemic per-conditioning: a novel therapy for acute stroke?

BACKGROUND AND PURPOSE: Remote ischemic preconditioning is a phenomenon by which a short period of sublethal ischemia to an organ protects against subsequent ischemia in another organ. We have recently demonstrated that remote ischemic conditioning by transient hind limb ischemia delivered during ischemia and before reperfusion can provide potent cardioprotection, a phenomenon we termed per-conditioning. This study evaluated whether remote ischemic per-conditioning may provide neuroprotection in a clinically relevant rat model of acute ischemic stroke. METHODS: Remote ischemic conditioning by transient limb ischemia was used in a rat transient middle cerebral artery occlusion model of acute stroke. A total of 39 P60 rats were randomly allocated to receive preconditioning, per-conditioning, or sham conditioning. Cerebral ischemia was maintained for 120 minutes followed by reperfusion. The resulting infarct size at 24 hours was quantified using computerized image analysis of 2-3-5-triphenyl tetrazolium chloride-stained brain sections. RESULTS: Compared with control, both pre- and per-conditioning significantly reduced brain infarct size with the more clinically relevant per-conditioning stimulus being superior to preconditioning. CONCLUSIONS: Remote per-conditioning by transient limb ischemia is a facile, clinically relevant stimulus that provides potent neuroprotection in a model of regional brain ischemia-reperfusion injury. Further studies are required to better understand the mechanisms and biology of this response before translation to randomized controlled trials of remote per-conditioning for acute ischemic stroke.

Remote ischaemic conditioning before hospital admission, as a complement to angioplasty, and effect on myocardial salvage in patients with acute myocardial infarction: a randomised trial.

BACKGROUND: Remote ischaemic preconditioning attenuates cardiac injury at elective surgery and angioplasty. We tested the hypothesis that remote ischaemic conditioning during evolving ST-elevation myocardial infarction, and done before primary percutaneous coronary intervention, increases myocardial salvage. METHODS: 333 consecutive adult patients with a suspected first acute myocardial infarction were randomly assigned in a 1:1 ratio by computerised block randomisation to receive primary percutaneous coronary intervention with (n=166 patients) versus without (n=167) remote conditioning (intermittent arm ischaemia through four cycles of 5-min inflation and 5-min deflation of a blood-pressure cuff). Allocation was concealed with opaque sealed envelopes. Patients received remote conditioning during transport to hospital, and primary percutaneous coronary intervention in hospital. The primary endpoint was myocardial salvage index at 30 days after primary percutaneous coronary intervention, measured by myocardial perfusion imaging as the proportion of the area at risk salvaged by treatment; analysis was per protocol. This study is registered with ClinicalTrials.gov, number NCT00435266. FINDINGS: 82 patients were excluded on arrival at hospital because they did not meet inclusion criteria, 32 were lost to follow-up, and 77 did not complete the follow-up with data for salvage index. Median salvage index was 0.75 (IQR 0.50-0.93, n=73) in the remote conditioning group versus 0.55 (0.35-0.88, n=69) in the control group, with median difference of 0.10 (95% CI 0.01-0.22; p=0.0333); mean salvage index was 0.69 (SD 0.27) versus 0.57 (0.26), with mean difference of 0.12 (95% CI 0.01-0.21; p=0.0333). Major adverse coronary events were death (n=3 per group), reinfarction (n=1 per group), and heart failure (n=3 per group). INTERPRETATION: Remote ischaemic conditioning before hospital admission increases myocardial salvage, and has a favourable safety profile. Our findings merit a larger trial to establish the effect of remote conditioning on clinical outcomes. FUNDING: Fondation Leducq.

Age-dependent effects of milrinone and levosimendan on ventricular function and haemodynamics in newborn and mature pigs.

Inodilators are used in the treatment of low cardiac output, mainly after cardiac surgery. At present, there is little knowledge of the effect of inodilators in the newborn heart. Immediately after birth and in the neonatal period, the metabolism and physiology of the heart undergo major changes. We hypothesised that effects of the inodilators milrinone and levosimendan on myocardial contractility and haemodynamics under normal physiological conditions were age dependent. Animal studies were conducted on 48 pigs using a closed-chest biventricular conductance catheter method. Pigs in two age groups, that is, 5-6 days and 5-6 weeks, were assigned to milrinone, levosimendan, or a control group. We observed that both milrinone - 19.2% with a p value of 0.05 - and levosimendan - 25.7% with a p value of 0.03 compared with the control group increased cardiac output, as well as myocardial contractility with a maximum pressure development over time: milrinone 28.2%, p = 0.01 and levosimendan 19.4%, p = 0.05. Milrinone improved diastolic performance (p < 0.05) in the left ventricle in the 5-6-week-old animals. In the newborn animals, neither of the inodilators increased ventricular contractility or cardiac output; however, we observed a significant decrease in the mean arterial pressure: milrinone 34.6%, p < 0.01 and levosimendan 30.1%, p = 0.02. Both inodilators demonstrated age-dependent haemodynamic effects, and it is noteworthy that neither milrinone nor levosimendan was able to increase cardiac output in the newborn heart.

Cardiovascular biomarkers in the evaluation of patent ductus arteriosus in very preterm neonates: A cohort study.

BACKGROUND: The evaluation of the patent ductus arteriosus (PDA) in the very premature neonate is a challenge. Echocardiography provides an interpretation of the hemodynamic condition. It is however, only a snapshot. Biomarkers may represent a physiological response to the hemodynamic alterations brought on by the PDA and may add to the identification of the clinical significant PDA. AIM: To investigate the association between mid regional proadrenomodulin (MR-proADM), N-terminal pro b-type natriuretic peptide (NT-proBNP), mid regional pro-atrial natriuretic peptide (MR-proANP), C-terminal pro endothelin-1 (CT-proET1) and copeptin and echocardiographic measures of PDA. STUDY DESIGN: Cohort study with echocardiography performed on day 3 and 6. Blood samples from day 3. SUBJECT: 139 consecutive neonates born at a gestational age <32 weeks. OUTCOME MEASURES: The main outcomes were presence of a PDA day 3 and 6, PDA diameter, left atrium to aorta ratio (LA:Ao-ratio), and descending aorta diastolic flow (DADF). RESULTS: Adjusted plasma levels of all investigated biomarkers, except CT-proET1, were found to be associated with both PDA diameter and LA:Ao-ratio, and also the presence of a large PDA. CT-proET1 and copeptin was found to be associated with abnormal DADF. Using pre-specified cut-off values NT-proBNP and MR-proANP day 3 seemed to be of value in identifying a large PDA day 3 and 6 in very preterm neonates. CONCLUSION: Among the investigated biomarkers NT-proBNP and MR-proANP performed best in relation to echocardiographic markers of PDA severity in very preterm neonates.

Remote ischemic conditioning in active ulcerative colitis: An explorative randomized clinical trial.

Remote ischemic conditioning (RIC) by repetitive brief periods of limb ischemia and reperfusion renders organs more resistant to ischemic injury. The protection is partly through down-regulation of the inflammatory response. Our aim was to investigate the clinical and anti-inflammatory effects of RIC in patients with active ulcerative colitis (UC). We included 22 patients with active UC in this explorative, randomized, sham-controlled clinical trial. The patients were randomly assigned 1:1 to RIC (induced in the arm through four cycles of 5-min inflation and 5-min deflation of a blood-pressure cuff) or sham (incomplete inflation of the blood-pressure cuff) once daily for 10 days. Outcome variables were measured at baseline and on day 11. When compared with sham, RIC did not affect inflammation in the UC patients measured by fecal calprotectin, plasma C-reactive protein, Mayo Score, Mayo Endoscopic Subscore, Nancy Histological Index or inflammatory cytokines involved in UC and RIC. The mRNA and miRNA expression profiles in the UC patients were measured by RNA sequencing and multiplexed hybridization, respectively, but were not significantly affected by RIC. We used the Langendorff heart model to assess activation of the organ protective mechanism induced by RIC, but could not confirm activation of the organ protective mechanism in the UC patients.

Preserved flow-mediated dilation in adults with cyanotic congenital heart disease.

Adults with cyanotic congenital heart disease (CCHD) have been shown to have endothelial dysfunction in the forearm resistance vessels as assessed with venous occlusion plethysmography. Whether these abnormalities are confined to the microvasculature or reflect generalized endothelial dysfunction remain unknown. We used high-resolution ultrasound to compare flow responses and endothelial-dependent flow-mediated dilation (FMD) in the brachial artery of 13 adult patients with CCHD and 14 healthy controls. High-dose vitamin C was infused to evaluate the possible role of reactive oxygen species on endothelial vasomotor function. FMD was measured both prior to and after vitamin C infusion. Sublingual glyceryl nitrate was given to assess endothelium-independent responses. FMD did not differ among patients with CCHD and controls either before (6.2 +/- 4.1, 5.1 +/- 2.6%, p = 0.44) or after (5.1 +/- 2.8, 5.2 +/- 3.1%, p = 0.90) vitamin C infusion. Endothelium-independent vasodilatation was similar in both groups (14.3 +/- 3.7, 13.2 +/- 4.4%). There were no differences in baseline flow or in measures of reactive hyperemia. Adults with CCHD appear to have preserved endothelial function in their conduit arteries. This suggests that these patients are not at an increased risk of premature atherosclerotic cardiovascular events.

Effect of Blood Flow Restricted Resistance Exercise and Remote Ischemic Conditioning on Functional Capacity and Myocellular Adaptations in Patients With Heart Failure.

BACKGROUND: Patients with congestive heart failure (CHF) have impaired functional capacity and inferior quality of life. The clinical manifestations are associated with structural and functional impairments in skeletal muscle, emphasizing a need for feasible rehabilitation strategies beyond optimal anticongestive medical treatment. We investigated whether low-load blood flow restricted resistance exercise (BFRRE) or remote ischemic conditioning (RIC) could improve functional capacity and quality of life in patients with CHF and stimulate skeletal muscle myofibrillar and mitochondrial adaptations. METHODS: We randomized 36 patients with CHF to BFRRE, RIC, or nontreatment control. BFRRE and RIC were performed 3× per week for 6 weeks. Before and after intervention, muscle biopsies, tests of functional capacity, and quality of life assessments were performed. Deuterium oxide was administered throughout the intervention to measure cumulative RNA and subfraction protein synthesis. Changes in muscle fiber morphology and mitochondrial respiratory function were also assessed. RESULTS: BFRRE improved 6-minute walk test by 39.0 m (CI, 7.0-71.1, P=0.019) compared with control. BFRRE increased maximum isometric strength by 29.7 Nm (CI, 10.8-48.6, P=0.003) compared with control. BFRRE improved quality of life by 5.4 points (CI, -0.04 to 10.9; P=0.052) compared with control. BFRRE increased mitochondrial function by 19.1 pmol/s per milligram (CI, 7.3-30.8; P=0.002) compared with control. RIC did not produce similar changes. CONCLUSIONS: Our results demonstrate that BFRRE, but not RIC, improves functional capacity, quality of life, and muscle mitochondrial function. Our findings have clinical implications for rehabilitation of patients with CHF and provide new insights on the myopathy accompanying CHF. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03380663.

Recycling endosomes in neuronal membrane traffic.

Neurons are highly polarized cells with axonal and somatodendritic membrane surfaces that spatially separate signal-sending from signal-receiving membrane domains. As found in many other cell types, different populations of endosomes are involved in the sorting of synaptic and other membrane cargo in neurons. The exact source of the membrane for neurite extension and process remodelling during neuronal differentiation has remained uncertain, and we do not know exactly how polarized sorting of neuronal membrane proteins is achieved. In the present article, we will provide a brief overview of endosomes and their putative or proven functions in fibroblasts, epithelial cells and neurons. On the basis of insights from non-neuronal cell types and recent studies on the function of recycling endosomes during synaptic plasticity-induced membrane remodelling, we postulate a speculative model regarding the role of recycling endosomes in neuronal differentiation.