Isoflurane Protects Against Human Endothelial Cell Apoptosis by Inducing Sphingosine Kinase-1 via ERK MAPK

Endothelial dysfunction is a major clinical problem affecting virtually every patient requiring critical care. Volatile anesthetics are frequently used during the perioperative period and protect the heart and kidney against ischemia and reperfusion injury. We aimed to determine whether isoflurane, the most commonly used volatile anesthetic in the USA, protects against endothelial apoptosis and necrosis and the mechanisms involved in this protection. Human endothelial EA.hy926 cells were pretreated with isoflurane or carrier gas (95% room air + 5% CO2) then subjected to apoptosis with tumor necrosis factor-α or to necrosis with hydrogen peroxide. DNA laddering and in situ Terminal Deoxynucleotidyl Transferase Biotin-dUTP Nick-End Labeling (TUNEL) staining determined EA.hy926 cell apoptosis and percent LDH released determined necrosis. We also determined whether isoflurane modulates the expression and activity of sphingosine kinase-1 (SK1) and induces the phosphorylation of extracellular signal regulated kinase (ERK MAPK) as both enzymes are known to protect against cell death. Isoflurane pretreatment significantly decreased apoptosis in EA.hy926 cells as evidenced by reduced TUNEL staining and DNA laddering without affecting necrosis. Mechanistically, isoflurane induces the phosphorylation of ERK MAPK and increased SK1 expression and activity in EA.hy926 cells. Finally, selective blockade of SK1 (with SKI-II) or S1P1 receptor (with W146) abolished the anti-apoptotic effects of isoflurane. Taken together, we demonstrate that isoflurane, in addition to its potent analgesic and anesthetic properties, protects against endothelial apoptosis most likely via SK1 and ERK MAPK activation. Our findings have significant clinical implication for protection of endothelial cells during the perioperative period and patients requiring critical care

The Effect of Nanofluid Volume Concentration on Heat Transfer and Friction Factor inside a Horizontal Tube

The additives of solid nanoparticles to liquids are significant enhancement of heat transfer and hydrodynamic flow. In this study, the thermal properties of three types of nanoparticles (Al2O3, TiO2, and SiO2) dispersed in water as a base fluid were measured experimentally. Forced convection heat transfer turbulent flow inside heated flat tube was numerically simulated. The heat flux around flat tube is 5000 W/m2 and Reynolds number is in the range of 5×103 to 50×103. CFD model by finite volume method used commercial software to find hydrodynamic and heat transfer coefficient. Simulation study concluded that the thermal properties measured and Reynolds number as input and friction factor and Nusselt number as output parameters. Data measured showed that thermal conductivity and viscosity increase with increasing the volume concentration of nanofluids with maximum deviation 19% and 6%, respectively. Simulation results concluded that the friction factor and Nusselt number increase with increasing the volume concentration. On the other hand, the flat tube enhances heat transfer and decreases pressure drop by 6% and −4%, respectively, as compared with circular tube. Comparison of numerical analysis with experimental data available showed good agreement with deviation not more than 2%

Experimental and analysis study on GloveMAP grasping force signal using Gaussian filtering method and principal component analysis (PCA)

This research paper presents the analysis study of human grasping forces for several objects by using a DataGlove called GloveMAP.The grasping force is generated from the bending of proximal and intermediate phalanges of the fingers when touching with a surface.A flexiforce sensor is installed at the finger’s position of the GloveMAP.The acquired grasping force signals are filtered by using a Gaussian filtering for the purpose of removing noises.A Principal Component Analysis technique (PCA) is employed to reduce the dimension of the grasping force signal, and follows by the extraction of its features.In the experiment, five subjects are selected to perform the grasping activities.The experimental results show that the Gaussian filter could be used to smoothen the grasping force signals. Moreover, the first and the second principal components of PCA could be used to extract features of grasping force signals

Learning and manipulating human's fingertip bending data for sign language translation using PCA-BMU classifier

Nowadays the classification of fingers movement could be used to classify or categorize many kinds of human finger motions including the classification of sign language for verbal communication.Principal Component Analysis (PCA) is one of classical method that capable to be verity the finger motions for various alphabets by reducing the dimensional dataset of finger movements.The objective of this paper is to analyze the human finger motions / movements between thumbs,index and middle fingers while bending the fingers using PCA-BMU based techniques. The used of low cost DataGlove “GloveMAP” which is based on fingers adapted postural movement (or EigenFingers) of the principal component was applied in order to translate the finger bending to the sign language alphabets. Preliminary experimental results have shown that the “GloveMAP” DataGlove capable to measure several human Degree of Freedom (DoF), by “translating” them into a virtual commands for the interaction in the virtual world

Utilization of inhaled nitric oxide after surgical repair of truncus arteriosus: A multicenter analysis

BackgroundElevated pulmonary vascular resistance (PVR) is common following repair of truncus arteriosus. Inhaled nitric oxide (iNO) is an effective yet costly therapy that is frequently implemented postoperatively to manage elevated PVR.ObjectivesWe aimed to describe practice patterns of iNO use in a multicenter cohort of patients who underwent repair of truncus arteriosus, a lesion in which recovery is often complicated by elevated PVR. We also sought to identify patient and center factors that were more commonly associated with the use of iNO in the postoperative period.DesignRetrospective cohort study.Setting15 tertiary care pediatric referral centers.PatientsAll infants who underwent definitive repair of truncus arteriosus without aortic arch obstruction between 2009 and 2016.InterventionsDescriptive statistics were used to demonstrate practice patterns of iNO use. Bivariate comparisons of characteristics of patients who did and did not receive iNO were performed, followed by multivariable mixed logistic regression analysis using backward elimination to identify independent predictors of iNO use.Main ResultsWe reviewed 216 patients who met inclusion criteria, of which 102 (46%) received iNO in the postoperative period: 69 (68%) had iNO started in the operating room and 33 (32%) had iNO initiated in the ICU. Median duration of iNO use was 4 days (range: 1‐21 days). In multivariable mixed logistic regression analysis, use of deep hypothermic circulatory arrest (odds ratio: 3.2; 95% confidence interval: 1.2, 8.4) and center (analyzed as a random effect, p = .02) were independently associated with iNO use.ConclusionsIn this contemporary multicenter study, nearly half of patients who underwent repair of truncus arteriosus received iNO postoperatively. Use of iNO was more dependent on individual center practice rather than patient characteristics. The study suggests a need for collaborative quality initiatives to determine optimal criteria for utilization of this important but expensive therapy.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/152533/1/chd12849_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/152533/2/chd12849.pd

Multicenter Analysis of Early Childhood Outcomes Following Repair of Truncus Arteriosus

Background Literature describing morbidity and mortality following truncus arteriosus repair is predominated by single-center reports. We created and analyzed a multicenter dataset to identify risk factors for late mortality and right ventricle-to-pulmonary artery (RV-PA) conduit reintervention for this patient population. Methods We retrospectively collected data on children who underwent repair of truncus arteriosus without concomitant arch obstruction at 15 centers between 2009 and 2016. Cox regression survival analysis was conducted to determine risk factors for late mortality, defined as death occurring after hospital discharge and greater than 30 days after surgery. Probability of any RV-PA conduit reintervention was analyzed over time using Fine-Gray modelling. Results We reviewed 216 patients, with median follow-up of 2.9 years (range:0.1-8.8). Operative mortaility occurred in 15 patients (7%). Of the 201 survivors, there were 14 (7%) late deaths. DiGeorge syndrome (HR:5.4; 95%CI:1.6-17.8) and need for postoperative tracheostomy (HR:5.9; 95%CI:1.8-19.4) were identified as independent risk factors for late mortality. At least one RV-PA conduit catheterization or surgical reintervention was performed in 109 patients (median time to reintervention:23 months, range:0.3-93). Risk factors for reintervention included use of pulmonary or aortic homografts versus Contegra® bovine jugular vein conduits (HR:1.9; 95%CI:1.2,3.1) and smaller conduit size (HR per mm/m2:1.05; 95%CI:1.03,1.08). Conclusions In a multicenter dataset, DiGeorge syndrome and need for tracheostomy postoperatively were found to be independent risk factors for late mortality after repair of truncus arteriosus, while risk of conduit reintervention was independently influenced by both initial conduit type and size

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

Study of Forced Convection Nanofluid Heat Transfer in the Automotive Cooling System

The heat transfer enhancement for many industrial applications by adding solid nanoparticles to liquids is significant topics in the last 10 years. This article included the friction factor and forced convection heat transfer of SiO2 nanoparticle dispersed in water as a base fluid conducted in a car radiator experimentally and numerically. Four different concentrations of nanofluids in the range of 1–2.5 vol% have been used. The flowrate changed in the range of 2–8 LPM to have Reynolds number with the range 500–1750. The results showed that the friction factor decreases with an increase in flowrate and increase with increasing in volume concentration. Furthermore, the inlet temperature to the radiator has insignificantly affected to the friction factor. On the other side, Nusselt number increases with increasing in flowrate, nanofluid volume concentration and inlet temperature. Meanwhile, application of SiO2 nanofluid with low concentrations can enhance heat transfer rate up to 50% as a comparison with pure water. The simulation results compared with experimental data, and there is a good agreement. Likewise, these results compared to other investigators to be validated

Simulation Study of Turbulent Convective Heat Transfer Enhancement in Heated Tube Flow Using Tio2-Water Nanofluid

Simulation by convenient software same as FLUENT was used to predict the friction factor and Nusselt number for forced convection heat transfer of TiO2-water nanofluid. The range of Reynolds number is from 10000 to 100000 to be turbulent flow in a horizontal straight tube with heat flux 5000 w/m2 around it. The volume fraction of nanoparticle was (0.25%, 0.5%, 0.75% and 1%) and diameter of particle is 27nm. The results show that the friction factor and Nusselt number are increasing with increasing of volume fraction. Results compared with the experimental data available in literature and there are good agreement

Numerical Study on Turbulent Forced Convective Heat Transfer Using Nanofluids TiO2 in an Automotive Cooling System

The limited thermal properties of liquids have led to the addition of solid nanoparticles to liquids in many industrial applications. In this paper, the friction factor and forced convection heat transfer of TiO2 nanoparticles dispersed in water in a car radiator was numerically determined. Four different nanofluid volume concentrations (1%, 2%, 3% and 4%) were used, and the resulting thermal properties were evaluated. The Reynolds number and inlet temperature ranged from 10000 to 100000 and from 60 to 90 °C, respectively. The results showed that the friction factor decreases as the Reynolds number increases and increases as the volume concentration increases. Additionally, the Nusselt number increases as the Reynolds number and volume concentration of the nanofluid increases. The TiO2 nanofluid at low concentrations can enhance the heat transfer efficiency up to 20% compared with that of pure water. There was good agreement among the CFD analysis and experimental data available in the literature