Effects of Lithium Ions on tPA-Induced Hemorrhagic Transformation under Stroke.

Thrombolytic therapy with the tissue plasminogen activator (tPA) is a therapeutic option for acute ischemic stroke. However, this approach is subject to several limitations, particularly the increased risk of hemorrhagic transformation (HT). Lithium salts show neuroprotective effects in stroke, but their effects on HT mechanisms are still unknown. In our study, we use the models of photothrombosis (PT)-induced brain ischemia and oxygen-glucose deprivation (OGD) to investigate the effect of Li+ on tPA-induced changes in brain and endothelial cell cultures. We found that tPA did not affect lesion volume or exacerbate neurological deficits but disrupted the blood-brain barrier. We demonstrate that poststroke treatment with Li+ improves neurological status and increases blood-brain barrier integrity after thrombolytic therapy. Under conditions of OGD, tPA treatment increased MMP-2/9 levels in endothelial cells, and preincubation with LiCl abolished this MMP activation. Moreover, we observed the effect of Li+ on glycolysis in tPA-treated endothelial cells, which we hypothesized to have an effect on MMP expression.

Neuroprotective Effects of Krypton Inhalation on Photothrombotic Ischemic Stroke.

This is the first in vivo study to investigate the neuroprotective effects of krypton on focal cerebral ischemia. The aim of the study was to analyze the effect of 2 h of inhalation of a krypton-oxygen mixture (Kr 70%/O2 30%) on the recovery of neurological functions and the degree of brain damage in rats after photoinduced ischemic stroke (PIS) and to investigate the possible mechanisms responsible for this neuroprotection. Experiments were performed on male Wistar rats weighing 250-300 g (n = 32). Animals were randomized into four groups. Two groups (n = 20) underwent photoinduced ischemic stroke, followed by 2 h of inhalation of krypton-oxygen mixture consisting of Kr 70%/O2 30% or a nitrogen-oxygen breathing mixture consisting of N2 70%/O2 30%, followed by neurological examinations on days 3 and 7. The other two groups (n = 12) received only gas mixtures of the same concentration and exposure duration as in those in the PIS groups, then Western blot analysis of the potential molecular mechanisms was performed. The results of the study show that treatment with the krypton-oxygen mixture consisting of Kr 70%/O2 30% improves the neurological status on day 7 of observation, reduces the lesion volume according to the MRI examination and the number of Iba-1- and caspase-3-positive cells in the damaged area, promotes the activation of neoangiogenesis (an increase in the von Willebrand factor), and reduces the penumbra area and the number of NeuN-positive cells in it on day 14 of observation. Inhalation of the krypton-oxygen mixture also significantly increases the levels of phosphorylated AKT kinase (protein kinase B) and glycogen synthase kinase 3b (pGSK3b) and promotes the expression of transcription factor Nrf2, which was accompanied by the lowered expression of transcription factor NFkB (p50). Thus, we showed pronounced neuroprotection induced by krypton inhalation after stroke and identified the signaling pathways that may be responsible for restoring neurological functions and reducing damage.

Three-Hour Argon Inhalation Has No Neuroprotective Effect after Open Traumatic Brain Injury in Rats.

In vivo studies of the therapeutic effects of argon in traumatic brain injury (TBI) are limited, and their results are contradictory. The aim of this study was to evaluate the effect of a three-hour inhalation of argon (70%Ar/30%O2) after an open TBI on the severity of the neurological deficit and the degree of brain damage in rats. The experiments were performed on male Wistar rats (n = 35). The TBI was simulated by the dosed open brain contusion injury. The animals were divided into three groups: sham-operated (SO, n = 7); TBI + 70%N2/30%O2 (TBI, n = 14); TBI + 70%Ar/30%O2 (TBI + iAr, n = 14). The Neurological status was assessed over a 14-day period (using the limb-placing and cylinder tests). Magnetic resonance imaging (MRI) scans and a histological examination of the brain with an assessment of the volume of the lesions were performed 14 days after the injury. At each of the time points (days 1, 7, and 14), the limb-placing test score was lower in the TBI and TBI + iAr groups than in the SO group, while there were no significant differences between the TBI and TBI + iAr groups. Additionally, no differences were found between these groups in the cylinder test scores (day 13). The volume of brain damage (tissue loss) according to both the MRI and histological findings did not differ between the TBI and TBI + iAr groups. A three-hour inhalation of argon (70%Ar/30%O2) after a TBI had no neuroprotective effect.

Effect of Xenon Treatment on Gene Expression in Brain Tissue after Traumatic Brain Injury in Rats.

The overactivation of inflammatory pathways and/or a deficiency of neuroplasticity may result in the delayed recovery of neural function in traumatic brain injury (TBI). A promising approach to protecting the brain tissue in TBI is xenon (Xe) treatment. However, xenon's mechanisms of action remain poorly clarified. In this study, the early-onset expression of 91 target genes was investigated in the damaged and in the contralateral brain areas (sensorimotor cortex region) 6 and 24 h after injury in a TBI rat model. The expression of genes involved in inflammation, oxidation, antioxidation, neurogenesis and neuroplasticity, apoptosis, DNA repair, autophagy, and mitophagy was assessed. The animals inhaled a gas mixture containing xenon and oxygen (ϕXe = 70%; ϕO2 25-30% 60 min) 15-30 min after TBI. The data showed that, in the contralateral area, xenon treatment induced the expression of stress genes (Irf1, Hmox1, S100A8, and S100A9). In the damaged area, a trend towards lower expression of the inflammatory gene Irf1 was observed. Thus, our results suggest that xenon exerts a mild stressor effect in healthy brain tissue and has a tendency to decrease the inflammation following damage, which might contribute to reducing the damage and activating the early compensatory processes in the brain post-TBI.

Long-Term Outcomes after Sepsis.

Sepsis is one of the most serious problems in modern medicine. Long-term outcomes in septic shock patients are very discouraging: 75% individuals who survived sepsis and septic shock demonstrate signs of organ failure and experience persistent functional deficit. Acute sepsis and its management in an intensive care unit (ICU) to a great extent determine the pathogenesis of further complications. We believe that the concept of phenoptosis proposed by Prof. Skulachev deserves a special attention from anesthesiologists and ICU doctors. According to this concept, septic shock is a suicidal mechanism of programmed organism death, which protects human population from dangerously infected individuals. The article suggests a potential approach to the sepsis treatment based on the notion that septic shock can be prevented by identification and blockade of receptors involved in the processing of phenoptotic signal induced by lipopolysaccharide and other substances that initiate septic shock. In view of this, the search for agents that can block molecular mechanisms of the phenoptotic signal transmission seems very promising.

Perioperative Dexmedetomidine Supplement Decreases Delirium Incidence After Adult Cardiac Surgery: A Randomized, Double-Blind, Controlled Study.

OBJECTIVE: Conflicting data exist on the effect of dexmedetomidine on delirium. For the present study, a randomized trial was performed to investigate the effect of perioperative dexmedetomidine on the rate of postoperative delirium after cardiac surgery. DESIGN: A randomized controlled trial. SETTING: University hospital. PARTICIPANTS: Patients (n = 169) undergoing elective cardiac surgery (coronary artery bypass graft surgery, valve surgery, or combined surgery) with cardiopulmonary bypass. INTERVENTIONS: Patients received a sevoflurane-based general anesthesia and were randomly assigned 1:1 to receive a dexmedetomidine infusion that started in the operating room (0.7 µg/kg/h) and continued into the intensive care unit (0.4 µg/kg/h) or an equivolume infusion of placebo. MEASUREMENTS AND MAIN RESULTS: A decrease in the rate of delirium in the dexmedetomidine group compared with the placebo group was demonstrated (6 of 84 [7.1%] v 16 of 85 [18.8%]; p = 0.02; odds ratio [OR] 0.33 [95% confidence interval {CI} 0.12-0.90]). Reduced intensive care unit and hospital lengths of stay also were observed (18 [18-22] hours v 22 [18-39] hours; p = 0.002 and 17 [7-20] days v 19 [8-21] days; p = 0.04, respectively). Mortality at 30 days was 2 (2.4%) in both groups. On multivariate analysis, only dexmedetomidine administration (OR 0.24 [95% CI 0.08-0.74]) and cardiopulmonary bypass time (OR 1.02 [95% CI 1.01-1.03] for increases of 1 min) were independent predictors of delirium development. CONCLUSIONS: Dexmedetomidine administered during and after general anesthesia for cardiac surgery with cardiopulmonary bypass decreased the rate of postoperative delirium and intensive care unit and hospital lengths of stay.

Nuclear DNA as Predictor of Acute Kidney Injury in Patients Undergoing Coronary Artery Bypass Graft: A Pilot Study.

OBJECTIVE: To measure the release of plasma nuclear deoxyribonucleic acid (DNA) and to assess the relationship between nuclear DNA level and acute kidney injury occurrence in patients undergoing cardiac surgery. SETTING: Cardiovascular anesthesiology and intensive care unit of a large tertiary-care university hospital. DESIGN: Prospective observational study. PARTICIPANTS: Fifty adult patients undergoing cardiac surgery. INTERVENTIONS: Nuclear DNA concentration was measured in the plasma. The relationship between the level of nuclear DNA and the incidence of acute kidney injury after coronary artery bypass grafting was investigated. MEASUREMENTS AND MAIN RESULTS: Cardiac surgery leads to significant increase in plasma nuclear DNA with peak levels 12 hours after surgery (median [interquartile range] 7.0 [9.6-22.5] µg/mL). No difference was observed between off-pump and on-pump surgical techniques. Nuclear DNA was the only predictor of acute kidney injury between baseline and early postoperative risk factors. CONCLUSIONS: The authors found an increase of nuclear DNA in the plasma of patients who had undergone coronary artery bypass grafting, with a peak after 12 hours and an association of nuclear DNA with postoperative acute kidney injury.

Sevoflurane Versus Total Intravenous Anesthesia for Isolated Coronary Artery Bypass Surgery With Cardiopulmonary Bypass: A Randomized Trial.

OBJECTIVE: Several studies have suggested that the cardioprotective effects of halogenated anesthetics in cardiac surgery result in reduced cardiac biomarker release compared with total intravenous anesthesia (TIVA). These findings came from relatively small randomized clinical trials and meta-analyses. The authors of this study hypothesized that the beneficial effects of volatile anesthetics translate into a reduced length of hospital stay after coronary artery bypass grafting surgery (CABG) with cardiopulmonary bypass. DESIGN: A randomized controlled trial. SETTING: Two university hospitals. PARTICIPANTS: Adult patients undergoing elective CABG surgery with cardiopulmonary bypass. INTERVENTIONS: Patients were assigned randomly to 2 following groups: propofol-based TIVA group (n = 431) and sevoflurane group (n = 437). MEASUREMENTS AND MAIN RESULTS: The primary endpoint was hospital length of stay, and the secondary endpoint included postoperative troponin T and N-terminal pro-brain natriuretic peptide release and mortality. In the sevoflurane group, a reduced length of hospital stay was observed compared with the propofol-based TIVA group (10 [9-11] days v 14 [10-16], p<0.001) as were reductions in cardiac troponin T release (0.18 ng/mL v 0.57 ng/mL at 24 hours, p<0.001), in N-terminal pro-brain natriuretic peptide release (633 pg/mL v 878 pg/mL at 24 hours, p<0.001; 482 pg/mL v 1,036 pg/mL at 48 hours, p<0.001), and in mortality at 1-year follow up (17.8% v 24.8%, p = 0.03). CONCLUSIONS: Anesthesia with sevoflurane reduced cardiac biomarker release and length of hospital stay after CABG with cardiopulmonary bypass surgery compared with propofol-based TIVA with a possible reduction in 1-year mortality.