Granzyme M has a critical role in providing innate immune protection in ulcerative colitis.

Inflammatory bowel disease (IBD) is an immunoregulatory disorder, associated with a chronic and inappropriate mucosal immune response to commensal bacteria, underlying disease states such as ulcerative colitis (UC) and Crohn's disease (CD) in humans. Granzyme M (GrzM) is a serine protease expressed by cytotoxic lymphocytes, in particular natural killer (NK) cells. Granzymes are thought to be involved in triggering cell death in eukaryotic target cells; however, some evidence supports their role in inflammation. The role of GrzM in the innate immune response to mucosal inflammation has never been examined. Here, we discover that patients with UC, unlike patients with CD, display high levels of GrzM mRNA expression in the inflamed colon. By taking advantage of well-established models of experimental UC, we revealed that GrzM-deficient mice have greater levels of inflammatory indicators during dextran sulfate sodium (DSS)-induced IBD, including increased weight loss, greater colon length reduction and more severe intestinal histopathology. The absence of GrzM expression also had effects on gut permeability, tissue cytokine/chemokine dynamics, and neutrophil infiltration during disease. These findings demonstrate, for the first time, that GrzM has a critical role during early stages of inflammation in UC, and that in its absence colonic inflammation is enhanced.

Microplastic in a macro filter feeder: Humpback whale Megaptera novaeangliae.

Marine filter feeders are exposed to microplastic because of their selection of small particles as food source. Baleen whales feed by filtering small particles from large water volumes. Macroplastic was found in baleen whales before. This study is the first to show the presence of microplastic in intestines of a baleen whale (Megaptera novaeangliae). Contents of its gastrointestinal tract were sieved, dissolved in 10% potassium hydroxide and washed. From the remaining dried material, potential synthetic polymer particles were selected based on density and appearance, and analysed by Fourier transform infrared (FTIR) spectroscopy. Several polymer types (polyethylene, polypropylene, polyvinylchloride, polyethylene terephthalate, nylon) were found, in varying particle shapes: sheets, fragments and threads with a size of 1mm to 17cm. This diversity in polymer types and particle shapes, can be interpreted as a representation of the varying characteristics of marine plastic and the unselective way of ingestion by M. novaeangliae.

A novel TLR2 agonist from Bordetella pertussis is a potent adjuvant that promotes protective immunity with an acellular pertussis vaccine.

Bordetella pertussis causes whooping cough, a severe and often lethal respiratory infection in infants. A recent resurgence of pertussis has been linked with waning or suboptimal immunity induced with acellular pertussis vaccines (Pa) that were introduced to most developed countries in the 1990s because of safety concerns around the use of whole-cell pertussis vaccines (Pw). Pa are composed of individual B. pertussis antigens absorbed to alum and promote strong antibody, T helper type 2 (Th2) and Th17 responses, but are less effective at inducing cellular immunity mediated by Th1 cells. In contrast, Pw, which include endogenous Toll-like receptor (TLR) agonists, induce Th1 as well as Th17 responses. Here we report the identification and characterization of novel TLR2-activating lipoproteins from B. pertussis. These proteins contain a characteristic N-terminal signal peptide that is unique to Gram-negative bacteria and we demonstrate that one of these lipoproteins, BP1569, activates murine dendritic cells and macrophages and human mononuclear cells via TLR2. Furthermore, we demonstrated that a corresponding synthetic lipopeptide LP1569 has potent immunostimulatory and adjuvant properties, capable of enhancing Th1, Th17, and IgG2a antibody responses induced in mice with an experimental Pa that conferred superior protection against B. pertussis infection than an equivalent vaccine formulated with alum.

Plasma epinephrine levels after epinephrine administration using different tracheal administration techniques in an adult CPR porcine model.

The aim of the study was to compare arterial plasma epinephrine levels after tracheal epinephrine application using three different tracheal instillation techniques at different tracheal levels in a porcine adult cardiopulmonary resuscitation model. In the prospective, randomized study, electrically-induced cardiopulmonary arrest was applied to 32 anaesthetized and paralyzed domestic pigs. After 3 min of cardiopulmonary arrest and 2 min of external chest compressions using a pneumatic compression device and mechanical ventilation, epinephrine was administered intravenously (20 microg/kg) or tracheally (50 microg/kg): using either direct injection into the upper end of the tracheal tube, via a catheter placed into the bronchial system and using a special tracheal application tube. In each group, there were eight pigs. Arterial blood samples were taken before and up to 10 min after epinephrine administration. Regression analysis was performed of the correlated data. The values of mean arterial blood pressure and end-tidal CO(2) during the time of observation did not differ between groups. Total plasma epinephrine concentrations showed a significant increase in all groups, but with no difference between the tracheal groups. However, peak epinephrine levels in the intravenous group were significantly higher than in tracheal groups. We conclude that administration using three different tracheal instillation levels result in similar onset and peak plasma epinephrine levels in this setting and therefore the preferred method of tracheal epinephrine application for cardiopulmonary resuscitation may be selected by other criteria.

Coagulation effects of a recently developed hydroxyethyl starch (HES 130/0.4) compared to hydroxyethyl starches with higher molecular weight.

BACKGROUND: Hydroxyethyl starches (HES) are known to interfere with blood coagulation according to molecular weight, the degree of substitution and the C2/C6 ratio. A recently developed low molecular hydroxyethyl starch (HES 130/0.4) was designed to reduce the blood compromising potency. METHODS: In this study, effects of a 30% in vitro haemodilution with the new HES preparation (HES 130/0.4) in comparison to HES 200/0.5, HES 450/0.7 and sodium chloride solution were investigated using intrinsic and extrinsic activated thrombelastography (TEG) and plasmatic coagulation tests. RESULTS: Whereas plasmatic tests revealed no prolongation of coagulation by HES in comparison to sodium chloride, the TEG variables clotting time, clot formation time and maximal clot firmness showed a significant (P<0.05) inhibition by all the HES preparations. The inhibition was most pronounced in HES 450 (P<0.05 vs HES 130) while HES 130 did not show a statistically significant difference in extrinsic activated maximal clot firmness when compared to sodium chloride. CONCLUSION: These in vitro results demonstrate that hydroxythyl starches especially compromise clot polymerisation. The new preparation HES 130/0.4 seems to inhibit platelet function to a lesser extent than hydroxyethyl starch preparations with a higher molecular weight and degree of substitution.

High-dose S(+)-ketamine improves neurological outcome following incomplete cerebral ischemia in rats.

PURPOSE: To determine the effects of the non-competitive NMDA-receptor antagonist S(+)-ketamine on neurological outcome in a rat model of incomplete cerebral ischemia. METHODS: Thirty rats were anesthetized, intubated and mechanically ventilated with isoflurane, O2 30% and nitrous oxide 70%. Following surgery animals were randomly assigned to one of the following treatment groups: Rats in group 1 (n = 10,OFF control) received fentanyl (bolus: 10 microg x kg(-1) i.v.; infusion 25 microg x kg(-1) x h(-1)) and N2O 70% / O2. Rats in group 2 (n = 10) received O2 30% in air and low-dose S(+)-ketamine (infusion: 0.25 mg x kg(-1) x min(-1)). Rats in group 3 (n = 10) received O2 30% in air and high-dose S(+)-ketamine (infusion: 1.0 mg x kg(-1) min(-1)). Following 30 min equilibration period ischemia was induced by combined unilateral common carotid artery ligation and hemorrhagic hypotension to 35 mm Hg for 30 min. Plasma catecholamines were assayed before and at the end of ischemia. Neurological deficit was evaluated for three postischemic days. RESULTS: Neurological outcome was improved with high-dose S(+)-ketamine when compared to fentanyl / N2O -anesthetized controls (9 vs. 1 stroke related deaths, P<0.05). Increases in plasma catecholamine concentrations were higher in fentanyl / N2O -anesthetized (adrenaline baseline 105.5+/-92.1 pg x ml(-1), during ischemia 948+/-602.8 pg x ml(-1), P<0.05; noradrenaline baseline 407+/-120.2 pg x ml(-1), ischemia 1267+/-422.2 pg x ml(-1), P <0.05) than in high-dose S(+)-ketamine-treated animals (adrenaline baseline 71+/-79.5 pg x ml(-1), ischemia 237 +/-131.9; noradrenaline baseline 317.9+/-310.5 pg x ml(-1), ischemia 310.5+/-85.7 pg x ml(-1)). CONCLUSION: Neurological outcome is improved following incomplete cerebral ischemia with S(+)-ketamine. Decreases in neuronal injury may be related to suppression of sympathetic discharge.

The time required to perform different methods for endotracheal drug administration during CPR.

We compared the times necessary to perform different endotracheal drug application techniques during CPR. In a simulated CPR situation with a mannequin 28 paramedics and seven emergency physicians performed different drug instillation techniques in a randomized manner: direct injection into the upper end of the endotracheal tube (group tube), via a suction catheter placed into the bronchial system (group suction catheter), via a flexible venous catheter placed into the bronchial system (group venous catheter), using an EDGAR tube (an endotracheal tube with an injection channel within the wall of the tube (group EDGAR). We measured the time necessary to prepare the drug solution and compared the time necessary to prepare and perform each instillation method and the time the ventilation was interrupted. Comparison between groups was performed by the Kruskal-Wallis test. It took significantly longer to perform the more complicated techniques using suction catheters (26; 18 54 s) and venous catheters (30; 22-50 s) compared to the other two groups (median; min-max) (p < 0.05). No differences concerning the application time were found between the group tube (7; 5 14 s) and group EDGAR (8; 5-13 s). The time of interruption of chest compression's and ventilation: group suction tube (11; 5-19 s) and group catheter (12; 6-18 s) was significant longer than in group tube (5; 2-9 s) (p < 0.05). In group EDGAR the connection ventilator-tube remained intact due to its concept of drug application. The use of special devices such as suction catheters or venous catheters for endotracheal instillation during CPR results in significantly longer preparation and instillation times with a longer interruption of the oxygen supply and chest compression's.

Desflurane and isoflurane improve neurological outcome after incomplete cerebral ischaemia in rats.

We have investigated the effects of isoflurane and desflurane on neurological outcome in a rat model of incomplete cerebral ischaemia. We studied 40 non-fasted male Sprague-Dawley rats, anaesthetized, intubated and ventilated mechanically with isoflurane and nitrous oxide in oxygen (FlO2 0.3). Arterial and venous catheters were inserted for measurement of arterial pressure, drug administration and blood sampling. A biparietal electroencephalogram (EEG) was recorded continuously using subdermal platinum electrodes. At completion of surgery, administration of isoflurane was discontinued (with the exception of those animals receiving isoflurane as treatment) and rats were allowed an equilibration period of 30 min according to the following procedure: group 1 (n = 10), 66% nitrous oxide in oxygen and fentanyl (bolus 10 micrograms kg-1 i.v. followed by infusion at a rate of 25 micrograms kg-1 h-1); group 2 (n = 10), 1.0 MAC of isoflurane in oxygen (FlO2 0.3) and air; groups 3 and 4 (n = 10 per group), 1.0 MAC or 1.5 MAC of desflurane in oxygen (FlO2 0.3) and air, respectively. Ischaemia was produced by combined unilateral common carotid artery ligation and haemorrhagic hypotension to 35 mm Hg for 30 min. Functional neurological deficit was evaluated for 3 days after cerebral ischaemia. At baseline, brain electrical activity was higher with fentanyl-nitrous oxide, 1.0 MAC of isoflurane and 1.0 MAC of desflurane (groups 1-3) compared with 1.5 MAC of desflurane (group 4). Neurological outcome was improved in isoflurane and desflurane anaesthetized animals (groups 2-4), regardless of the concentration used compared with fentanyl-nitrous oxide anaesthesia (group 1). The increase in plasma epinephrine and norepinephrine concentrations during ischaemia was significantly higher in fentanyl-nitrous oxide anaesthetized animals (group 1) compared with animals who received volatile anaesthetics (groups 2-4). These data suggest that cerebral protection produced by isoflurane and desflurane appears to be related to reduction in sympathetic activity rather than suppression of cerebral metabolic rate.

Plasma catecholamine levels following tracheal and intravenous epinephrine administration in swine.

We compared plasma epinephrine levels after three different tracheal epinephrine application techniques and intravenous injection in male and female anesthetized and paralyzed domestic pigs. Epinephrine was administered intravenously (10 microg/kg) (group i.v.) or tracheally (100 microg/kg) either by direct injection into the upper end of the tracheal tube (group Tube), via a suction tube placed into the bronchial system (group Catheter) or using an EDGAR tube (group EDGAR), each group: n = 8. Arterial plasma samples were drawn before and 0.5, 1, 1.5, 2, 2.5, 3, 4, 5, 6, 7 and 10 min after epinephrine administration. Plasma concentrations of epinephrine were measured with high pressure liquid chromatography using electrochemical detection. Analysis was performed by regression analysis for correlated data. Total plasma epinephrine concentrations showed a significant increase within 0.5 min in all groups. However, peak plasma epinephrine levels in group i.v. were significantly higher than in tracheal groups, while no differences between tracheal groups over the time were found. We conclude that in swine with spontaneous circulation tracheal instillation techniques using special devices such as suction tubes or EDGAR tubes result in onset and peak plasma epinephrine levels equivalent to those after direct injection into the upper end of the tracheal tube.

Intravenous clonidine decreases minimum end-tidal isoflurane for induction of electroencephalographic burst suppression.

The aim of this study was to determine the individual end-tidal isoflurane (ET ISO) threshold concentration for the induction of electroencephalographic (EEG) burst suppression with and without intravenous (I.V.) clonidine and to evaluate the EEG and cardiovascular response to skin incision during isoflurane/N2O anesthesia. Thirty-nine patients (ASA physical status I or II, 20-68 yr of age) undergoing orthopedic surgery were randomly assigned to receive I.V. saline (n = 20) or I.V. clonidine (3 microg/kg, n = 19). After detection of isoflurane-induced burst suppression, ET ISO was decreased in 0.1% ET steps until burst suppression diminished. Median minimum ET ISO for induction of burst suppression was 1.4% in the saline group and 0.9% in the clonidine group (P < 0.05). Before skin incision, EEG alpha 2 activity was significantly higher in the clonidine group compared with saline group. Fourteen patients (70%) in the saline group and 12 patients (63%) in the clonidine group showed a cardiovascular response to skin incision. After skin incision, EEG alpha 2 power was significantly decreased in both groups. A significant increase of delta activity was only found in the saline group. We conclude that the known minimum alveolar anesthetic concentration reduction of clonidine seems to be due to a direct cerebral action.

Preoperative acute hypervolemic hemodilution with hydroxyethylstarch: an alternative to acute normovolemic hemodilution?

Acute normovolemic hemodilution (ANH) may help to reduce demand for homologous blood but requires extra time and apparatus. A more simple procedure is acute hypervolemic hemodilution (HHD), where hydroxyethylstarch is administered preoperatively without removal of blood. In a prospectively randomized study we compared ANH (preoperatively 15 mL/kg autologous blood removal and replacement with 15 mL/kg of hydroxyethylstarch with HHD (15 mL/kg of hydroxyethylstarch administered preoperatively) in 49 patients undergoing hip arthroplasty. To avoid excessive intravascular volume, we used the vasodilating effect of isoflurane. No significant differences were found between groups (ANH, n = 23; HHD, n = 26) for intraoperative blood loss (ANH versus HHD, median [minimum-maximum]); 545 [295-785] mL versus 520 [315-825] mL) and postoperative blood loss (730 [525-945] mL versus 780 [495-895] mL), postoperative hemoglobin, hemotocrit, platelet count or coagulation variables, and transfusion requirements (ANH 43% versus HHD 35% of patients received homologous blood) (P > 0.05). Heart rate did not change significantly in either group. In the ANH group mean arterial blood pressure (MAP) decreased after hemodilution (P < 0.05) while in the HHD group MAP did not change over time. Mean time required to perform ANH was 58 (46-62) min versus HHD 16 (12-19) min (P < 0.05). Costs for ANH were $63.60 USD and for HHD $32.75 USD (labor costs not included). In orthopedic patients undergoing hip replacement with a predicted blood loss of about 1000 mL, HHD seems to be a simple as well as time- and cost-saving alternative for ANH.

[Attempt at a definition of the individual anesthesia level by repetitive pain stimulation: correlation with EEG findings]. / Versuch einer Definition des individuellen Anästhesieniveaus über repetitive Schmerzreizung: Korrelation mit EEG-Befunden.

AIM: Previous studies using EEG for assessment of depth of anaesthesia correlate anaesthetic concentration with the anaesthetic stage. This procedure neglects the well known effect of individual different susceptibility to anaesthetics. Thus, patients receiving similar concentrations of anaesthetics may not necessarily be at the same level of "anaesthetic depth". The aim of this study was to define an interindividual comparable level of anaesthesia by recording the autonomic cardiovascular reaction to a standardised painful stimulus (tetanic stimulus, 80 mA, 100 Hz). METHODS: In 61 patients undergoing orthopaedic surgery general anaesthesia was performed with isoflurane in 66% N2O. Starting from 0.4% isoflurane, endtidal isoflurane concentration was increased in a stepwise manner (0.1% isoflurane) until the patient did not show any relevant cardiovascular reaction (increase of heart rate and/or blood pressure < 10%) after tetanic stimulation of the ulnar nerve. If patients demonstrated no haemodynamic changes at 0.4% isoflurane, the concentration was decreased until a relevant cardiovascular reaction was registered. During each steady state period multichannel EEG was recorded and mean values of power density (median: microV2/Hz) were computed. RESULTS: Comparing EEG-results between both groups exhibiting a cardiovascular reaction (CVR+ , median endtidal Iso: 0.5%) and without reaction (CVR- , median endtidal Iso: 0.6%) an increase in low frequency bands and a significant decrease in high frequencies was found (Wilcoxon-test, p < 0.05). In contrast, comparing EEG-data only in relation to endtidal isoflurane concentration neglecting individual haemodynamic responses, no differences of power density in high frequency bands were detected. CONCLUSION: This method to define individual depth of anaesthesia as described, results in more consistent EEG patterns and may be useful in relating EEG to depth of anaesthesia.

[Anesthesia with low fresh gas flow in clinical routine use]. / Anästhesie mit niedrigem Frischgasfluss in der klinischen Routine.

Anaesthesia in low-flow techniques gains increasing interest. The possibility of cost reduction, widespread use of highly developed anaesthesia machines and monitors, and introduction of two new fluorinated inhalational anaesthetics with low solubility in human tissues encourage the use of low-flow anaesthesia techniques. Further advantages are improved climatisation of breathing gas and estimation or even measurement of the important parameter "oxygen consumption". The anaesthesia machines and inhalational anaesthetics currently available allow a safe use of low-flow techniques if safety requirements are complied with (tight circle system, monitoring of: inspired oxygen concentration, minute ventilation, airway pressure, transcutaneous oxygen saturation). Low-flow anaesthesia techniques using a fresh gas flow rate of 1 l/min can be performed with almost every anaesthesia machine. However, the use of multigas monitors, analyzing most parts of the breathing gas, facilitates the use of low-flow techniques. Multigas monitors and anaesthesia machines equipped with intermittent fresh gas delivery are recommended for the use of fresh gas flow rates close to the metabolic rate. Because of its physicochemical properties the new inhalational anaesthetic desflurane offers advantages for the use in low-flow anaesthesia techniques.

[EEG changes during sedation with gamma-hydroxybutyric acid]. / EEG-Veränderungen unter Sedierung mit gamma-Hydroxybuttersäure (GHB).

Gamma-hydroxybutyric acid (GHB) is a naturally occurring transmitter in the mammalian brain, related to sleep regulation and possibly to energy balance in diving or hibernating animals. It has been used for almost 35 years as an intravenous agent for induction of anaesthesia and for long-term sedation. Its convincing pharmacological properties, without serious adverse effects on circulation or respiration, are compromised by its unpredictable duration of action. This is not a major problem with long-term sedation during ICU treatment. GHB has been used with good results for sedation of patients with severe brain injury, where it compares favourably with barbiturates. In animal studies, it seems to possess a protective action against hypoxia on a cellular and whole organ level. However, in some experimental animals GHB has been shown to produce seizure-like activities, and the compound is being used to produce absence-like seizures. GHB has been used in our ICU for years to provide adequate sedation for patients under controlled ventilation or for patients fighting the respirator during spontaneous respiration. No serious side effects were observed in these patients, while in some patients under haemodialysis hypernatraemia and metabolic alkalosis developed; both were reversible after discontinuation of GHB and restriction of additional sodium input (Somsanit, the commercially available GHB preparation in Germany, contains 9.2 mmol sodium/g; the daily dose averages 20-40 g GHB, i.e. 180-370 mmol sodium). PATIENTS AND METHODS. In 31 patients after major abdominal surgery, sedation was established with GHB 50 mg/kg BW injected via perfusion pump over a 20-min period. No centrally acting medication had been given for at least 2 h. A computer-based multichannel EEG system (CATEEM, MediSyst, Linden) was used, allowing for fast Fourier transformation, spectral analysis and topographical brain mapping. EEG during induction of sedation was followed after a baseline EEG (10 min) had been recorded. Patients receiving long-term sedation were studied daily for an additional 15-min period. Corresponding well to the clinical findings, EEG pattern changed to a slow delta-theta or delta-only rhythm within 10 min of the start of injection. Alpha and beta power decreased, while delta activity exhibited an increase. All changes were most obvious in frontal and central areas of the brain. In about one out of three patients, a burst--suppression pattern developed. Since automatic processing of EEG may fail to detect special patterns like the looked-for 3/s spikes and waves, the raw EEG was analysed visually by an expert neurologist. Both processed and conventionally analysed EEG were free of any seizure-like electrical activity. CONCLUSION. We conclude that animal data may not apply to the use of GHB in humans, provided the dose is limited to the clinical needs. GHB is used in clinical practice in doses twice as high, or even higher, than the one we use for induction, without obvious side effects. However, the suppression of theta rhythm we observed in about half of the patients studied may indicate that even less than 50 mg/kg BW might be sufficient for adequate sedation.