Low-tidal-volume prevent ventilation induced inflammation in a mouse model of sepsis.

BACKGROUND AND GOAL OF THE STUDY: Pulmonary inflammation, increased vascular permeability, and pulmonary edema, occur in response to primary pulmonary infections like pneumonia but are also evident in endotoxemia or sepsis. Mechanical ventilation augments pre-existing lung injury and inflammation resulting from exposure to microbial products. The objective of this study was to test the hypothesis that low-tidal-volume prevent ventilation induced lung injury in sepsis. MATERIALS AND METHODS: 10-12-week-old male C57BL/6N-mice received an intraperitoneal (i.p.) injection with equipotent dosages of LPS, 1668-thioate, 1612-thioate, or PBS. 120 min after injection, mice were randomized to low- (LV, 7 ± 1 ml/kg) or high-tidal-volume (HV, 25 ± 1 ml/kg) ventilation. Hemodynamic and ventilatory parameters were recorded and inflammatory markers were analyzed form BAL that was generated after 90 minute ventilation. RESULTS AND DISCUSSION: Arterial blood pressures declined during mechanical ventilation in all groups. pO2 decreased in LPS injected and CO2 increased in sham, LPS, and 1612-thioate administered mice at 45 min and in 1668-thioate injected mice after 90 minute LV ventilation compared to respective HV groups. BAL protein concentrations increased in HV ventilated and 1668- or 1612-thioat pre-treated mice. BAL TNF-α protein concentrations increased in both LPS- and 1668-thioate-injected and IL-1ß protein concentrations only in LPS-injected and HV ventilated mice. Most notably, no increased protein concentrations were observed in any of the LV ventilated groups. CONCLUSION: We conclude that low-tidal-volume ventilation may be a potential strategy for the prevention of ventilator induced lung injury in a murine model of systemic TLR agonist induced lung injury.

Improve hip fracture outcome in the elderly patient (iHOPE): a study protocol for a pragmatic, multicentre randomised controlled trial to test the efficacy of spinal versus general anaesthesia.

INTRODUCTION: Hip fracture surgery is associated with high in-hospital and 30-day mortality rates and serious adverse patient outcomes. Evidence from randomised controlled trials regarding effectiveness of spinal versus general anaesthesia on patient-centred outcomes after hip fracture surgery is sparse. METHODS AND ANALYSIS: The iHOPE study is a pragmatic national, multicentre, randomised controlled, open-label clinical trial with a two-arm parallel group design. In total, 1032 patients with hip fracture (>65 years) will be randomised in an intended 1:1 allocation ratio to receive spinal anaesthesia (n=516) or general anaesthesia (n=516). Outcome assessment will occur in a blinded manner after hospital discharge and inhospital. The primary endpoint will be assessed by telephone interview and comprises the time to the first occurring event of the binary composite outcome of all-cause mortality or new-onset serious cardiac and pulmonary complications within 30 postoperative days. In-hospital secondary endpoints, assessed via in-person interviews and medical record review, include mortality, perioperative adverse events, delirium, satisfaction, walking independently, length of hospital stay and discharge destination. Telephone interviews will be performed for long-term endpoints (all-cause mortality, independence in walking, chronic pain, ability to return home cognitive function and overall health and disability) at postoperative day 30±3, 180±45 and 365±60. ETHICS AND DISSEMINATION: iHOPE has been approved by the leading Ethics Committee of the Medical Faculty of the RWTH Aachen University on 14 March 2018 (EK 022/18). Approval from all other involved local Ethical Committees was subsequently requested and obtained. Study started in April 2018 with a total recruitment period of 24 months. iHOPE will be disseminated via presentations at national and international scientific meetings or conferences and publication in peer-reviewed international scientific journals. TRIAL REGISTRATION NUMBER: DRKS00013644; Pre-results.

Synthetic CpG oligonucleotides induce a genetic profile ameliorating murine myocardial I/R injury.

We previously demonstrated that pre-conditioning with CpG oligonucleotide (ODN) 1668 induces quick up-regulation of gene expression 3 hours post-murine myocardial ischaemia/reperfusion (I/R) injury, terminating inflammatory processes that sustain I/R injury. Now, performing comprehensive microarray and biocomputational analyses, we sought to further enlighten the "black box" beyond these first 3 hours. C57BL/6 mice were pretreated with either CpG 1668 or with control ODN 1612, respectively. Sixteen hours later, myocardial ischaemia was induced for 1 hour in a closed-chest model, followed by reperfusion for 24 hours. RNA was extracted from hearts, and labelled cDNA was hybridized to gene microarrays. Data analysis was performed with BRB ArrayTools and Ingenuity Pathway Analysis. Functional groups mediating restoration of cellular integrity were among the top up-regulated categories. Genes known to influence cardiomyocyte survival were strongly induced 24 hours post-I/R. In contrast, proinflammatory pathways were down-regulated. Interleukin-10, an upstream regulator, suppressed specifically selected proinflammatory target genes at 24 hours compared to 3 hours post-I/R. The IL1 complex is supposed to be one regulator of a network increasing cardiovascular angiogenesis. The up-regulation of numerous protective pathways and the suppression of proinflammatory activity are supposed to be the genetic correlate of the cardioprotective effects of CpG 1668 pre-conditioning.

Decreased Secondary Lesion Growth and Attenuated Immune Response after Traumatic Brain Injury in Tlr2/4-/- Mice.

Danger-associated molecular patterns are released by damaged cells and trigger neuroinflammation through activation of non-specific pattern recognition receptors, e.g., toll-like receptors (TLRs). Since the role of TLR2 and 4 after traumatic brain injury (TBI) is still unclear, we examined the outcome and the expression of pro-inflammatory mediators after experimental TBI in Tlr2/4-/- and wild-type (WT) mice. Tlr2/4-/- and WT mice were subjected to controlled cortical injury and contusion volume and brain edema formation were assessed 24 h thereafter. Expression of inflammatory markers in brain tissue was measured by quantitative PCR 15 min, 3 h, 6 h, 12 h, and 24 h after controlled cortical impact (CCI). Contusion volume was significantly attenuated in Tlr2/4-/- mice (29.7 ± 0.7 mm3 as compared to 33.5 ± 0.8 mm3 in WT; p < 0.05) after CCI while brain edema was not affected. Only interleukin (IL)-1ß gene expression was increased after CCI in the Tlr2/4-/- relative to WT mice. Inducible nitric oxide synthetase, TNF, IL-6, and COX-2 were similar in injured WT and Tlr2/4-/- mice, while the increase in high-mobility group box 1 was attenuated at 6 h. TLR2 and 4 are consequently shown to potentially promote secondary brain injury after experimental CCI via neuroinflammation and may therefore represent a novel therapeutic target for the treatment of TBI.

Tlr2 deficiency does not limit the development of left ventricular hypertrophy in a model of transverse aortic constriction induced pressure overload.

BACKGROUND: Toll-like receptors (TLRs) are involved in a variety of cardiovascular disorders, including septic cardiomyopathy, ischemia/reperfusion, heart failure, and cardiac hypertrophy. Previous research revealed that TLR4 promotes cardiac hypertrophy in vivo. Therefore, we investigated whether TLR2 is also involved in the development of cardiac hypertrophy. METHODS: Tlr2 deficient and wild type mice were subjected to transverse aortic constriction (TAC) or sham operation procedure. Left ventricular, heart and lung weights as well as hemodynamic parameters were determined after 3, 14 or 28 days. Real-time RT PCR was used to evaluate left ventricular gene expression. Protein content was determined via ELISA. RESULTS: TAC increased systolic left ventricular pressure, contraction and relaxations velocities as well as the heart weight in both genotypes. Tlr2 deficiency significantly enhanced cardiac hypertrophy after 14 and 28 days of TAC. Left ventricular end-diastolic pressure and heart rate increased in Tlr2(-/-) TAC mice only. Fourteen days of TAC led to a significant elevation of ANP, BNP, TGFß and TLR4 mRNA levels in Tlr2(-/-) left ventricular tissue. CONCLUSION: These data suggest that Tlr2 deficiency may promote the development of cardiac hypertrophy and ventricular remodeling after transverse aortic constriction.

Antifungal antibiotics modulate the pro-inflammatory cytokine production and phagocytic activity of human monocytes in an in vitro sepsis model.

AIMS: The incidence of secondary systemic fungal infections has sharply increased in bacterial septic patients. Antimycotics exhibit immunomodulatory properties, yet these effects are incompletely understood in secondary systemic fungal infections following bacterial sepsis. We investigated a model of systemic inflammation to determine whether antimycotics (liposomal amphotericin B (L-AMB), itraconazol (ITC), and anidulafungin (ANI)) modulate the gene and protein expression as well as the phagocytic activity of lipopolysaccharide (LPS)-stimulated human monocytes. MAIN METHODS: THP-1 monocytes were incubated with L-AMB, ITC or ANI and LPS. Gene expression levels of cytokines (TNF-, IL-1, IL-6, and IL-10) were measured after 2h, 6h, and 24h. Cytokine protein levels were evaluated after 24h and phagocytic activity was determined following co-incubation with Escherichia coli. KEY FINDINGS: All antimycotics differentially modulated the gene and protein expression of cytokines in sepsis-like conditions. In the presence of LPS, we identified L-AMB as immunosuppressive, whereas ITC demonstrated pro-inflammatory properties. Both compounds induced remarkably less phagocytosis. SIGNIFICANCE: Our study suggests that antimycotics routinely used in septic patients alter the immune response in sepsis-like conditions by modulating cytokine gene and protein expression levels and phagocytic activity. Future treatment strategies should consider the immune status of the host and apply antimycotics accordingly in bacterial septic patients with secondary fungal infections.

Ultrasound confirmation of central venous catheter position via a right supraclavicular fossa view using a microconvex probe: an observational pilot study.

BACKGROUND: Visualisation of a central venous catheter (CVC) with ultrasound is restricted to the internal jugular vein (IJV). CVC tip position is confirmed by chest radiography, intracardiac ECG or transoesophageal/transthoracic echocardiography (TEE/TTE). OBJECTIVE: We explored the feasibility, safety and accuracy of a right supraclavicular view for visualisation of the lower superior vena cava (SVC) and the right pulmonary artery (RPA) as an ultrasound landmark for real-time ultrasound-guided CVC tip positioning via the right IJV. Ultrasound was then compared with chest radiography. DESIGN: An observational pilot study. SETTING: Bonn, University Hospital, Germany. From July to October 2012. PATIENTS: Fifty-one patients scheduled for elective surgery. Reasons for exclusion were emergency procedure, thrombosis or small IJV lumen and mechanical obstacle to guidewire advancement. INTERVENTION: In 48 patients, CVC insertion via the right IJV and progress of the guidewire into the lower SVC were continuously guided by an ultrasound transducer in the right supraclavicular fossa. MAIN OUTCOME MEASURES: CVC tip position in lower SVC and tip-to-carina distance were assessed with chest radiography as a reference method and additionally with TEE in cardiothoracic patients. Insertion depth was compared with intracardiac ECG and body-height formula. RESULTS: The guidewire tip was seen in the SVC of all patients. In four patients, the tip was not visible in proximity of the RPA. Chest radiography and TEE confirmed CVC tip position in the lower SVC (zone A). Bland-Altman analysis revealed an average of difference of 1.6 cm for ultrasound versus ECG (95% limit of agreement -2 to 5 cm) and an average of difference of 1 cm for ultrasound versus body-height formula (95% limit of agreement -2 to 4 cm). CONCLUSION: Ultrasound via a right supraclavicular view is a feasible, well tolerated and accurate approach and should be further explored. Chest radiography confirmed CVC position in the lower SVC.

Postconditioning with a CpG containing oligodeoxynucleotide ameliorates myocardial infarction in a murine closed-chest model.

AIMS: Toll-like receptor (TLR)9 ligand CpG-oligodeoxynucleotide (CpG-ODN) exerts preconditioning in myocardial ischemia/reperfusion. We hypothesized a postconditioning effect of CpG-ODN in a murine closed-chest model of myocardial infarction. MATERIALS AND METHODS: C57BL/6 (12 weeks, male, WT) mice were instrumented at the left anterior descending artery, then allowed 5d of recovery before 30 min ischemia. Treatments comprised: 1) PBS: 250 µl phosphate buffer solution intraperitoneally 5 min before reperfusion and 2) IPC (ischemic postconditioning): 3 twenty-second reperfusion and occlusion episodes at the end of ischemia 3) CpG-ODN: 1668 thioate 0.2 µmol/kg BW intraperitoneally 5 min before reperfusion. Infarct size was assessed via triphenyltetrazolium chloride (TTC) staining after 2 and 24h reperfusion. Myocardial mRNA-expression of cytokines was measured using real-time PCR after 2h reperfusion. Phosphatidylinositol-3 kinase (PI3K)-inhibitor wortmannin was injected intraperitoneally in WT 15 min before postconditioning and PBS in each group. Cardiac function in WT was assessed with a left-ventricular pressure-volume catheter at 24h reperfusion. KEY FINDINGS: Following 30 min ischemia and 2h reperfusion, infarct size was diminished by 90% in WT postconditioned with CpG-ODN (2.4 ± 1.55 IS/AAR%) and IPC (1.98 ± 1.03 IS/AAR%) compared to PBS mice (23.2 ± 3.97 IS/AAR%). Infarct size increased following 24h reperfusion but the differences remained robust. Expression of TNF-α and IL-10 was increased in CpG-ODN. Wortmannin abolished the postconditioning effect of CpG-ODN and IPC. Ejection fraction and preload-recruitable stroke work were significantly greater in CpG-ODN mice. SIGNIFICANCE: CpG-ODN confers postconditioning via activation of TLR9. Cardiac function is preserved following CpG-ODN postconditioning. The PI3K -inhibitor wortmannin attenuates CpG-ODN postconditioning.

Antibiotics regulate the immune response in both presence and absence of lipopolysaccharide through modulation of Toll-like receptors, cytokine production and phagocytosis in vitro.

The inflammatory response to pathogen-associated molecular patterns such as lipopolysaccharide (LPS) in sepsis is mediated via Toll-like receptors (TLRs). Since TLRs also trigger various immune functions, including phagocytosis, their modulation is a promising strategy in the treatment of sepsis. As antibiotics have immunomodulatory properties, this study examined the effect of commonly used classes of antibiotics on i) the expression of TLRs and cytokines and ii) the phagocytic activity under sepsis-like conditions in vitro. This was achieved by incubating THP-1 monocytes and peripheral blood mononuclear cells (PBMCs) obtained from patients after open-heart surgery with the addition of LPS and six key antibiotics (piperacillin, doxycycline, erythromycin, moxifloxacin or gentamicin). After 24h, mRNA levels of both cytokines (IL-1ß, IL-6) and TLRs (1, 2, 4, and 6) were monitored and phagocytosis was determined following coincubation with Escherichia coli. Each antibiotic differentially regulated the gene expression of the investigated TLRs and cytokines in monocytes. Erythromycin, moxifloxacin and doxycyclin displayed the strongest effects and changed mRNA-levels of the investigated genes up to 5.6-fold. Consistent with this, antibiotics and, in particular, moxifloxacin, regulated the TLR-and cytokine expression in activated PBMCs obtained from patients after open-heart surgery. Furthermore, piperacillin, doxycyclin and moxifloxacin inhibited the phagocytic activity of monocytes. Our results suggest that antibiotics regulate the immune response by modulating TLR- and cytokine expression as well as phagocytosis under septic conditions. Moxifloxacin, doxycycline and erythromycin were shown to possess the strongest immunomodulatory effects and these antibiotic classes should be considered for future immunomodulatory studies in sepsis.

TLR2 stimulation induces cardiac inflammation but not cardiac depression in vivo.

BACKGROUND: Bacteria such as Staphylococcus aureus induce myocardial dysfunction in vivo. To rectify conflicting evidence about the role of TLR2 signaling and cardiac dysfunction, we hypothesized that the specific TLR2 agonist purified lipoteichoic acid (LTA) from S. aureus contributes to cardiac dysfunction in vitro and in vivo. METHODS: Wildtype (WT-) and TLR2-deficient (TLR2-D) mice were challenged with LTA and in comparison with equivalent doses of lipopolysaccharide (LPS) and CpG-oligodeoxynucleotide (CpG-ODN). TLR2-expression, NFκB as well as cytokine response were determined. Sarcomere shortening of isolated cardiomyocytes was analyzed in vitro and cardiac function in vivo after stimulation with LTA. RESULTS: LTA induced up-regulation of TLR2 mRNA, activation of NFκB and cytokine expression within 2-6 h in WT-, but not in TLR2-D hearts. Cytokines were also elevated in the serum. LPS and CpG-ODN induced a more severe cardiac inflammation. In vitro incubation of cardiomyocytes with LTA reduced sarcomere shortening via NO at stimulation frequencies ≤ 8 Hz only in WT cells. However, hemodynamic parameters in vivo were not affected by LTA challenge. CONCLUSIONS: LTA induced cardiac inflammation was relatively weak and sarcomere shortening was reduced only below physiological heart rates. This may explain the apparent contradiction between the in vivo and in vitro LTA effects.

Anti-atherogenic effects of statins: Impact on angiopoietin-2 release from endothelial cells.

Beyond lipid lowering, statins are supposed to exert pleiotropic effects positively influencing the progression of atherosclerotic lesions. The development of such lesions is associated with increased release of angiopoietin-2 (Ang-2), an endothelial cell-specific protein growth factor stored in Weibel-Palade bodies (WPBs). The aim of our study was to examine whether statin pretreatment influences the release of Ang-2 from endothelial cells. Stimulation of HUVECs and HMVECs with PMA, thrombin or histamine resulted in significant release of Ang-2, as evidenced by ELISA. Pretreatment with simvastatin and mevastatin suppressed this release to basal level, while pravastatin had no effect. Simvastatin itself increased nitric oxide (NO, EC number 1.14.13.39) synthesis, measured by Griess reaction. Combining the statin pretreatment with the eNOS inhibitor L-NNA as well as bypassing the HMG-CoA reductase (EC number: 1.1.1.34) by adding mevalonic acid or geranyl pyrophosphate restored the exocytotic effect of PMA. Immunofluorescence microscopy showed that depletion of WPBs upon PMA stimulation ceased after pretreatment with simvastatin. This study demonstrates a potent suppressive effect of statins on the release of Ang-2 from endothelial cells. Regarding its harmful effects in the development of atherosclerotic lesions, our data provide further insight into the mechanisms of the anti-atherogenic potential of statins.

Toll-like receptor 9 promotes cardiac inflammation and heart failure during polymicrobial sepsis.

BACKGROUND: Aim was to elucidate the role of toll-like receptor 9 (TLR9) in cardiac inflammation and septic heart failure in a murine model of polymicrobial sepsis. METHODS: Sepsis was induced via colon ascendens stent peritonitis (CASP) in C57BL/6 wild-type (WT) and TLR9-deficient (TLR9-D) mice. Bacterial load in the peritoneal cavity and cardiac expression of inflammatory mediators were determined at 6, 12, 18, 24, and 36 h. Eighteen hours after CASP cardiac function was monitored in vivo. Sarcomere length of isolated cardiomyocytes was measured at 0.5 to 10 Hz after incubation with heat-inactivated bacteria. RESULTS: CASP led to continuous release of bacteria into the peritoneal cavity, an increase of cytokines, and differential regulation of receptors of innate immunity in the heart. Eighteen hours after CASP WT mice developed septic heart failure characterised by reduction of end-systolic pressure, stroke volume, cardiac output, and parameters of contractility. This coincided with reduced cardiomyocyte sarcomere shortening. TLR9 deficiency resulted in significant reduction of cardiac inflammation and a sustained heart function. This was consistent with reduced mortality in TLR9-D compared to WT mice. CONCLUSIONS: In polymicrobial sepsis TLR9 signalling is pivotal to cardiac inflammation and septic heart failure.

A rare case of direct tumor extension to the right ventricle.

We report the case of a 72-year-old woman with signs of pulmonary embolism and right heart failure. Echocardiographic imaging and computed tomography revealed a mass within the inferior vena cava reaching from the head of the pancreas to the right ventricle. From standard imaging procedures and clinical findings alone, differentiation of a cardiac thrombus from a metastatic tumor mass was difficult. After resection of the intravascular tumor, histopathologic analysis confirmed a metastasis of primary ductal pancreatic adenocarcinoma. This is a report of a case of mucinous adenocarcinoma of the pancreas reaching the heart by continuous intravascular spreading.

Priming with synthetic oligonucleotides attenuates pressure overload-induced inflammation and cardiac hypertrophy in mice.

AIMS: Inflammation and Toll-like receptor (TLR) signalling have been linked to the development of cardiac hypertrophy following transverse aortic constriction (TAC). In the present study, we investigated whether pre-treatment with the synthetic TLR9 ligands 1668-thioate or 1612-thioate modulates the progression of TAC-induced cardiac inflammation and hypertrophy. METHODS AND RESULTS: C57BL/6N-mice were pre-treated with 1668-thioate, 1612-thioate (0.25 nmol/g, i.p.), or phosphate-buffered saline 16 h prior to TAC or sham surgery. Heart-weight/body-weight ratio (HW/BW), cardiomyocyte cell size, cellular macrophage accumulation, myofibroblast differentiation, and collagen deposition were investigated for up to 28 days. Cardiac function was monitored using a pressure-volume catheter and M-mode echocardiography. Inflammatory gene expression in the heart was analysed via gene array, while the time course of mRNA expression of key inflammatory mediators was assessed via RT-qPCR. TAC increased the HW/BW ratio and cardiomyocyte cell size and induced macrophage accumulation, myofibroblast differentiation, and collagen deposition. These changes were accompanied by cardiac inflammation and a significant loss of left ventricular function. Pre-treatment with cytosine-phosphate-guanine (CpG)-containing 1668-thioate attenuated the inflammatory response, the progression of cardiac hypertrophy, and cardiac remodelling, which resulted in a prolonged preservation of left ventricular function. These changes were induced to a smaller extent by the use of the non-CG-containing oligodeoxynucleotide 1612-thioate. CONCLUSION: Pre-treatment with 1668-thioate attenuated cardiac hypertrophy following pressure overload, possibly by modifying the hypertrophy-induced inflammatory response, thereby reducing cardiac growth and fibrosis as well as delaying loss of cardiac function.

Vascular dysfunction following polymicrobial sepsis: role of pattern recognition receptors.

AIMS: Aim was to elucidate the specific role of pattern recognition receptors in vascular dysfunction during polymicrobial sepsis (colon ascendens stent peritonitis, CASP). METHODS AND RESULTS: Vascular contractility of C57BL/6 (wildtype) mice and mice deficient for Toll-like receptor 2/4/9 (TLR2-D, TLR4-D, TLR9-D) or CD14 (CD14-D) was measured 18 h following CASP. mRNA expression of pro- (Tumor Necrosis Factor-α (TNFα), Interleukin (IL)-1ß, IL-6) and anti-inflammatory cytokines (IL-10) and of vascular inducible NO-Synthase (iNOS) was determined using RT-qPCR. Wildtype mice exhibited a significant loss of vascular contractility after CASP. This was aggravated in TLR2-D mice, blunted in TLR4-D animals and abolished in TLR9-D and CD14-D animals. TNF-α expression was significantly up-regulated after CASP in wildtype and TLR2-D animals, but not in mice deficient for TLR4, -9 or CD14. iNOS was significantly up-regulated in TLR2-D animals only. TLR2-D animals showed significantly higher levels of TLR4, -9 and CD14. Application of H154-ODN, a TLR9 antagonist, attenuated CASP-induced cytokine release and vascular dysfunction in wildtype mice. CONCLUSIONS: Within our model, CD14 and TLR9 play a decisive role for the development of vascular dysfunction and thus can be effectively antagonized using H154-ODN. TLR2-D animals are more prone to polymicrobial sepsis, presumably due to up-regulation of TLR4, 9 and CD14.

Remote ischaemic preconditioning for heart surgery. The study design for a multi-center randomized double-blinded controlled clinical trial--the RIPHeart-Study.

AIMS: Transient ischaemia of non-vital tissue has been shown to enhance the tolerance of remote organs to cope with a subsequent prolonged ischaemic event in a number of clinical conditions, a phenomenon known as remote ischaemic preconditioning (RIPC). However, there remains uncertainty about the efficacy of RIPC in patients undergoing cardiac surgery. The purpose of this report is to describe the design and methods used in the "Remote Ischaemic Preconditioning for Heart Surgery (RIPHeart)-Study". METHODS: We are conducting a prospective, randomized, double-blind, multicentre, controlled trial including 2070 adult cardiac surgical patients. All types of surgery in which cardiopulmonary bypass is used will be included. Patients will be randomized either to the RIPC group receiving four 5 min cycles of transient upper limb ischaemia/reperfusion or to the control group receiving four cycles of blood pressure cuff inflation/deflation at a dummy arm. The primary endpoint is a composite outcome (all-cause mortality, non-fatal myocardial infarction, any new stroke, and/or acute renal failure) until hospital discharge. CONCLUSION: The RIPHeart-Study is a multicentre trial to determine whether RIPC may improve clinical outcome in cardiac surgical patients.

Sinus venous thrombosis: a differential diagnosis of postpartum headache.

In this report, we describe a patient who developed severe headache following epidural analgesia for labor and delivery. Although the epidural puncture had been reported to be uneventful, headache was initially suspected to result from an accidental dural puncture. After the headache worsened, a sinus venous thrombosis was suspected and subsequently confirmed by magnetic resonance imaging. This case highlights the difficulty of differential diagnosis of headache in the postnatal period in patients after EDA and stresses the necessity of considering alternative pathologies.

In vivo Toll-like receptor 4 antagonism restores cardiac function during endotoxemia.

Severe sepsis and septic shock are often accompanied by acute cardiovascular depression. Lipopolysaccharide (LPS) signaling via Toll-like receptor 4 (TLR4) can induce septic organ dysfunction. The aim of this study was to elucidate the in vivo impact of pharmacological TLR4 antagonism on LPS-induced cardiovascular depression using eritoran tetrasodium (E5564). To simulate sepsis, C3H/HeN mice were challenged i.p. with 2 mg/kg body weight LPS. With the intent to antagonize the LPS effects, eritoran was administered i.v. (4 mg/kg body weight). Physical activity, peripheral blood pressure, and heart frequency were recorded before and after LPS and eritoran injection. In addition, intracardiac hemodynamic parameters were analyzed with a pressure conductance catheter. After 2 and 6 h of LPS stimulation ± eritoran treatment, the hearts and aortae were harvested, and TLR as well as inflammatory mediator expression was measured using reverse transcription-quantitative polymerase chain reaction and enzyme-linked immunosorbent assay. Lipopolysaccharide significantly decreased arterial blood pressure over time. Administration of eritoran partially prevented the LPS-dependent reduction in blood pressure and preserved cardiac function. In addition, LPS increased the expression of CD14 and TLR2 in cardiac and aortic tissue. In aortic tissue, eritoran attenuated this increase, whereas no significant reduction was observed in the heart. Furthermore, cardiac and aortic inducible nitric oxide synthetase mRNA levels were significantly increased 6 h after LPS application. This effect was reduced in the presence of eritoran. In summary, the beneficial influence of eritoran on cardiovascular function in vivo seems to rely mainly on reduction of LPS-induced inducible nitric oxide synthetase expression as well as on attenuated cytokine expression in the vascular wall.

The toll-like receptor 4-antagonist eritoran reduces murine cardiac hypertrophy.

AIMS: Toll-like receptor 4 (TLR4) recognizes lipopolysaccharides and endogenous ligands released after organ injury. Deficiency of TLR4 attenuates the development of left ventricular hypertrophy after transverse aortic constriction (TAC) in mice. We hypothesized that application of the TLR4 antagonist eritoran may also reduce cardiac hypertrophy after TAC surgery. METHODS AND RESULTS: A catheter was implanted into the jugular vein of C57BL/6 mice to allow repeated administration of eritoran (5 mg/kg body weight) or placebo. Three days after TAC or sham surgery, heart weights were determined and cardiac tissue underwent mRNA and protein quantification. The TAC placebo group exhibited a significant increase in left ventricular weight, left ventricular weight/tibia length, and left ventricular/body weight ratio compared with the sham and TAC eritoran groups. Natriuretic peptide mRNA was elevated significantly only in TAC placebo mice. Transverse aortic constriction surgery led to a distinct increase in interleukin (IL)-1ß and IL-6 mRNA and protein expression in the placebo but not the eritoran group. In contrast, IL-10 was significantly increased in both eritoran groups independent from TAC. Matrix metalloproteinase zymographic activity was highest in TAC placebo animals. CONCLUSION: Application of the TLR4 antagonist eritoran attenuates the development of cardiac hypertrophy possibly by a reduction in inflammatory and increase in anti-inflammatory cytokines.