Neuroprotective Effects of Inhaled Xenon Gas on Brain Structural Gray Matter Changes After Out-of-Hospital Cardiac Arrest Evaluated by Morphometric Analysis: A Substudy of the Randomized Xe-Hypotheca Trial.

BACKGROUND: We have earlier reported that inhaled xenon combined with hypothermia attenuates brain white matter injury in comatose survivors of out-of-hospital cardiac arrest (OHCA). A predefined secondary objective was to assess the effect of inhaled xenon on the structural changes in gray matter in comatose survivors after OHCA. METHODS: Patients were randomly assigned to receive either inhaled xenon combined with target temperature management (33 °C) for 24 h (n = 55, xenon group) or target temperature management alone (n = 55, control group). A change of brain gray matter volume was assessed with a voxel-based morphometry evaluation of high-resolution structural brain magnetic resonance imaging (MRI) data with Statistical Parametric Mapping. Patients were scheduled to undergo the first MRI between 36 and 52 h and a second MRI 10 days after OHCA. RESULTS: Of the 110 randomly assigned patients in the Xe-Hypotheca trial, 66 patients completed both MRI scans. After all imaging-based exclusions, 21 patients in the control group and 24 patients in the xenon group had both scan 1 and scan 2 available for analyses with scans that fulfilled the quality criteria. Compared with the xenon group, the control group had a significant decrease in brain gray matter volume in several clusters in the second scan compared with the first. In a between-group analysis, significant reductions were found in the right amygdala/entorhinal cortex (p = 0.025), left amygdala (p = 0.043), left middle temporal gyrus (p = 0.042), left inferior temporal gyrus (p = 0.008), left parahippocampal gyrus (p = 0.042), left temporal pole (p = 0.042), and left cerebellar cortex (p = 0.005). In the remaining gray matter areas, there were no significant changes between the groups. CONCLUSIONS: In comatose survivors of OHCA, inhaled xenon combined with targeted temperature management preserved gray matter better than hypothermia alone. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov: NCT00879892.

Effect of Inhaled Xenon on Cardiac Function in Comatose Survivors of Out-of-Hospital Cardiac Arrest-A Substudy of the Xenon in Combination With Hypothermia After Cardiac Arrest Trial.

This explorative substudy aimed at determining the effect of inhaled xenon on left ventricular function by echocardiography in comatose survivors of out-of-hospital cardiac arrest. DESIGN: A randomized two-group single-blinded phase 2 clinical drug trial. SETTING: A multipurpose ICU in two university hospitals. PATIENTS: Of the 110 randomized comatose survivors after out-of-hospital cardiac arrest with a shockable rhythm in the xenon in combination with hypothermia after cardiac arrest trial, 38 patients (24-76 yr old) with complete echocardiography were included in this study. INTERVENTIONS: Patients were randomized to receive either inhaled xenon combined with hypothermia (33°C) for 24 hours or hypothermia treatment alone. Echocardiography was performed at hospital admission and 24 ± 4 hours after hypothermia. MEASUREMENTS AND MAIN RESULTS: Left ventricular ejection fraction, myocardial longitudinal systolic strain, and diastolic function were analyzed blinded to treatment. There were 17 xenon and 21 control patients in whom echocardiography was completed. Clinical characteristics did not differ significantly between the groups. At admission, ejection fraction was similar in xenon and control patients (39% ± 10% vs 38% ± 11%; p = 0.711) but higher in xenon than control patients after hypothermia (50% ± 10% vs 42% ± 10%; p = 0.014). Global longitudinal systolic strain was similar in xenon and control patients at admission (-9.0% ± 3.8% vs -8.1% ± 3.6%; p = 0.555) but better in xenon than control patients after hypothermia (-14.4.0% ± 4.0% vs -10.5% ± 4.0%; p = 0.006). In patients with coronary artery disease, longitudinal strain improved in the nonischemic myocardial segments in xenon patients. There were no changes in diastolic function between the groups. CONCLUSIONS: Among comatose survivors of a cardiac cause out-of-hospital cardiac arrest, inhaled xenon combined with hypothermia was associated with greater recovery of left ventricular systolic function in comparison with hypothermia alone.

Inhaled Xenon Attenuates Myocardial Damage in Comatose Survivors of Out-of-Hospital Cardiac Arrest: The Xe-Hypotheca Trial.

BACKGROUND: The authors previously reported that inhaled xenon combined with hypothermia attenuates brain white matter injury in comatose survivors of out-of-hospital cardiac arrest (OHCA). OBJECTIVES: A pre-defined secondary objective was to assess the effect of inhaled xenon on myocardial ischemic damage in the same study population. METHODS: A total of 110 comatose patients who had experienced OHCA from a cardiac cause were randomized to receive either inhaled xenon (40% end-tidal concentration) combined with hypothermia (33°C) for 24 h (n = 55; xenon group) or hypothermia treatment alone (n = 55; control group). Troponin-T levels were measured at hospital admission, and at 24 h, 48 h, and 72 h post-cardiac arrest. All available cases were analyzed for troponin-T release. RESULTS: Troponin-T measurements were available from 54 xenon patients and 54 control patients. The baseline characteristics did not differ significantly between the groups. After adjustments for age, sex, study site, primary coronary percutaneous intervention (PCI), and norepinephrine dose, the mean ± SD post-arrival incremental change of the ln-transformed troponin-T at 72 h was 0.79 ± 1.54 in the xenon group and 1.56 ± 1.38 in the control group (adjusted mean difference -0.66; 95% confidence interval: -1.16 to -0.16; p = 0.01). The effect of xenon on the change in the troponin-T values did not differ in patients with or without PCI or in those with a diagnosis of ST-segment elevation myocardial infarction (group by PCI or ST-segment elevation myocardial infarction interaction effect; p = 0.86 and p = 0.71, respectively). CONCLUSIONS: Among comatose survivors of OHCA, in comparison with hypothermia alone, inhaled xenon combined with hypothermia suggested a less severe myocardial injury as demonstrated by the significantly reduced release of troponin-T.

Preoperative stenting in oesophageal cancer has no effect on survival: a propensity-matched case-control study.

OBJECTIVES: Previous studies have shown a link between oesophageal stenting before oesophagectomy and worse oncological outcomes. Our objective was to determine the effect of preoperative self-expanding covered metallic stent (SEMS) on survival, progression-free survival (PFS), operative time and complication rates in oesophageal cancer (EC). METHODS: This study included EC patients undergoing surgery between January 2006 and January 2014 with a cT2 tumour or higher ( n = 174; 135 adenocarcinomas and 39 squamous cell carcinomas). We propensity matched 1:1 a preoperative SEMS group ( n = 30) to a control group. Despite the propensity matching, statistically non-significant residual covariate imbalances persisted. Median follow-up time was 33 months (range: 0-118 months). We performed Kaplan-Meier survival analysis for OS and PFS, the Student's t -test for operative time and the chi-squared test for complication rates. RESULTS: Median survival in the SEMS group was 28.5 months (range: 0-116 months) vs 34 months (4-118 months) in the control group and median PFS was 22 months (0-111 months) vs 27 (4-113 months) ( P = 0.748 and P = 0.764, respectively). Mean operative times between groups were 436 min vs 375 min ( P = 0.017). No differences emerged in intraoperative (23.3% vs 10%, P = 0.299), early (50.0% vs 46.7%, P = 1) or late complication rates (53.3% vs 43.3%, P = 0.606). CONCLUSIONS: SEMS application has no significant effect on survival, PFS or complications. Mean operative time was significantly higher in the SEMS insertion group. We therefore conclude that preoperative SEMS insertion makes the operation more challenging by increasing operative time, but is otherwise a feasible and safe strategy in experienced centres as a bridge to surgery.

Effect of Inhaled Xenon on Cerebral White Matter Damage in Comatose Survivors of Out-of-Hospital Cardiac Arrest: A Randomized Clinical Trial.

IMPORTANCE: Evidence from preclinical models indicates that xenon gas can prevent the development of cerebral damage after acute global hypoxic-ischemic brain injury but, thus far, these putative neuroprotective properties have not been reported in human studies. OBJECTIVE: To determine the effect of inhaled xenon on ischemic white matter damage assessed with magnetic resonance imaging (MRI). DESIGN, SETTING, AND PARTICIPANTS: A randomized single-blind phase 2 clinical drug trial conducted between August 2009 and March 2015 at 2 multipurpose intensive care units in Finland. One hundred ten comatose patients (aged 24-76 years) who had experienced out-of-hospital cardiac arrest were randomized. INTERVENTIONS: Patients were randomly assigned to receive either inhaled xenon combined with hypothermia (33°C) for 24 hours (n = 55 in the xenon group) or hypothermia treatment alone (n = 55 in the control group). MAIN OUTCOMES AND MEASURES: The primary end point was cerebral white matter damage as evaluated by fractional anisotropy from diffusion tensor MRI scheduled to be performed between 36 and 52 hours after cardiac arrest. Secondary end points included neurological outcome assessed using the modified Rankin Scale (score 0 [no symptoms] through 6 [death]) and mortality at 6 months. RESULTS: Among the 110 randomized patients (mean age, 61.5 years; 80 men [72.7%]), all completed the study. There were MRI data from 97 patients (88.2%) a median of 53 hours (interquartile range [IQR], 47-64 hours) after cardiac arrest. The mean global fractional anisotropy values were 0.433 (SD, 0.028) in the xenon group and 0.419 (SD, 0.033) in the control group. The age-, sex-, and site-adjusted mean global fractional anisotropy value was 3.8% higher (95% CI, 1.1%-6.4%) in the xenon group (adjusted mean difference, 0.016 [95% CI, 0.005-0.027], P = .006). At 6 months, 75 patients (68.2%) were alive. Secondary end points at 6 months did not reveal statistically significant differences between the groups. In ordinal analysis of the modified Rankin Scale, the median (IQR) value was 1 (1-6) in the xenon group and 1 (0-6) in the control group (median difference, 0 [95% CI, 0-0]; P = .68). The 6-month mortality rate was 27.3% (15/55) in the xenon group and 34.5% (19/55) in the control group (adjusted hazard ratio, 0.49 [95% CI, 0.23-1.01]; P = .053). CONCLUSIONS AND RELEVANCE: Among comatose survivors of out-of-hospital cardiac arrest, inhaled xenon combined with hypothermia compared with hypothermia alone resulted in less white matter damage as measured by fractional anisotropy of diffusion tensor MRI. However, there was no statistically significant difference in neurological outcomes or mortality at 6 months. These preliminary findings require further evaluation in an adequately powered clinical trial designed to assess clinical outcomes associated with inhaled xenon among survivors of out-of-hospital cardiac arrest. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00879892.

Activating transcription factor 3 is a positive regulator of human IFNG gene expression.

IL-12 and IL-18 are essential for Th1 differentiation, whereas the role of IFN-alpha in Th1 development is less understood. In this microarray-based study, we searched for genes that are regulated by IFN-alpha, IL-12, or the combination of IL-12 plus IL-18 during the early differentiation of human umbilical cord blood CD4(+) Th cells. Twenty-six genes were similarly regulated in response to treatment with IL-12, IFN-alpha, or the combination of IL-12 plus IL-18. These genes could therefore play a role in Th1 lineage decision. Transcription factor activating transcription factor (ATF) 3 was upregulated by these cytokines and selected for further study. Ectopic expression of ATF3 in CD4(+) T cells enhanced the production of IFN-gamma, the hallmark cytokine of Th1 cells, whereas small interfering RNA knockdown of ATF3 reduced IFN-gamma production. Furthermore, ATF3 formed an endogenous complex with JUN in CD4(+) T cells induced to Th1. Chromatin immunoprecipitation and luciferase reporter assays showed that both ATF3 and JUN are recruited to and transactivate the IFNG promoter during early Th1 differentiation. Collectively, these data indicate that ATF3 promotes human Th1 differentiation.

IL-12 up-regulates T-bet independently of IFN-gamma in human CD4+ T cells.

T-bet is an important Th1 driving transcription factor regulated by IFN-gamma/STAT1 pathway. T-bet turns on IFN-gamma transcription in CD4+ T cells and T-bet-deficient cells fail to differentiate to Th1 direction. Previous reports have characterized function of T-bet mainly in murine cells and very little is known about its functions in human cells. Here, we studied T-bet expression kinetics in parallel with GATA3 during Th1/Th2 polarization. We demonstrate that in addition to CD3/CD28 activation, cytokines IL-12 and IFN-alpha in the presence of neutralizing anti-IFN-gamma enhanced T-bet mRNA and protein expression in human CD4+ cells. T-bet is known to be a potent inducer of IFN-gamma. Even though IFN-gamma and IL-12 stimulation induced similar levels of T-bet protein in human CD4+ cells, IFN-gamma-treated cells produced considerably less IFN-gamma than cells treated with IL-12. Therefore, high T-bet protein expression does not necessarily correlate with IFN-gamma production. In addition, we show that the immunosuppressive cytokine TGF-beta inhibits T-bet and GATA3 protein expression only if it is present prior to primary T cell activation and is maintained in the cultures during the early polarization of Th1/Th2 cells. In conclusion, we report new insights into the cytokine regulation of T-bet in human CD4+ T cells.

Expression of human pim family genes is selectively up-regulated by cytokines promoting T helper type 1, but not T helper type 2, cell differentiation.

Cytokines are the most important inducers of T helper (Th) cell differentiation. Interleukin-12 (IL-12) and interferon-alpha (IFN-alpha) are responsible for human Th1-cell differentiation, while IL-4 is the critical cytokine promoting Th2-cell development. These two subsets of cells co-ordinate immunological responses to pathogens as well as autoimmune or allergic reactions. The pim family of proto-oncogenes encodes serine/threonine-specific kinases involved in cytokine-mediated signalling pathways in haematopoietic cells. Here we demonstrate that expression of pim-1 and pim-2 mRNAs is selectively up- or down-regulated in human cord-blood-derived CD4+ cells freshly induced to polarize towards Th1 or Th2 cells, respectively, whereas their expression is inhibited in both cell types by the immunosuppressive transforming growth factor beta (TGF-beta). Moreover, the Th1-specific cytokines IL-12 and IFN-alpha, but not the Th2-specific cytokine IL-4, transiently up-regulate pim-1 and pim-2 mRNA expression in human peripheral blood T cells and natural killer cells. In addition, the Pim-1 protein levels are strongly up-regulated by Th1-specific cytokines in all of these cell types. Taken together, our results suggest that pim genes and their protein products are involved in the early differentiation process of T helper cells.

New separation-free assay technique for SNPs using two-photon excitation fluorometry.

A new separation-free method for detection of single nucleotide polymorphisms (SNPs) is described. The method is based on the single base extension principle, fluorescently labeled dideoxy nucleotides and two-photon fluorescence excitation technology, known as ArcDia trade mark TPX technology. In this assay technique, template-directed single base extension is carried out for primers which have been immobilized on polymer microparticles. Depending on the sequence of the template DNA, the primers are extended either with a labeled or with a non-labeled nucleotide. The genotype of the sample is determined on the basis of two-photon excited fluorescence of individual microparticles. The effect of various assay condition parameters on the performance of the assay method is studied. The performance of the new assay method is demonstrated by genotyping the SNPs of human individuals using double-stranded PCR amplicons as samples. The results show that the new SNP assay method provides sensitivity and reliability comparable to the state-of-the-art SNaPshot trade mark assay method. Applicability of the new method in routine laboratory use is discussed with respect to alternative assay techniques.

Kinetics and STAT4- or STAT6-mediated regulation of genes involved in lymphocyte polarization to Th1 and Th2 cells.

Many genes implicated in Th1 and Th2 differentiation have been identified in both human and mouse. However, the functional roles and hierarchy of these factors in the signaling pathways leading to either Th1 or Th2 responses are less clear. To explore at which stage of polarization the differences between Th1 and Th2 cells occur, we have studied the expression of 23 key genes implicated in the process during the first week of polarization from human precursor T helper cells using quantitative real-time reverse transcription-PCR. According to our results, 14 of the genes were clearly regulated differentially in Th1 and Th2 conditions in distinct time-dependent patterns, either during the first 2 days or after 1 week of polarization. Furthermore, 6 of these genes were identified to be targets of STAT4/6 regulation. Thus, for the first time we demonstrate expression kinetics of a number of key genes involved in Th1 and Th2 differentiation during the first week of polarization in both human and mouse. In addition, our study shows for the first time that the genes BCL-6 and TRADD are differentially regulated during the polarization of human Th1 and Th2 cells.