@article{MuellenbachRoewerKranke2013,
  author    = {M{\"u}llenbach, Ralf Michael and Roewer, Norbert and Kranke, Peter},
  title     = {Quality Assurance Would Be Welcome},
  series = {Deutsches {\"A}rzteblatt international},
  volume    = {110},
  journal   = {Deutsches {\"A}rzteblatt international},
  number    = {27-28},
  doi       = {10.3238/arztebl.2013.0485a},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128844},
  pages     = {485},
  year      = {2013},
  abstract  = {No abstract available.},
  language  = {en}
}
@article{SchusterJohannsenRoewer2013,
  author    = {Schuster, Frank and Johannsen, Stephan and Roewer, Norbert},
  title     = {A Minimal-Invasive Metabolic Test Detects Malignant Hyperthermia Susceptibility in a Patient after Sevoflurane-Induced Metabolic Crisis},
  series = {Case Reports in Anesthesiology},
  journal   = {Case Reports in Anesthesiology},
  doi       = {10.1155/2013/953859},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-97080},
  year      = {2013},
  abstract  = {Malignant hyperthermia is a rare but life-threatening complication of general anesthesia in predisposed patients usually triggered by potent inhalation anesthetics and/or the depolarizing muscle relaxant succinylcholine. The authors present a case of delayed sevoflurane-induced malignant hyperthermia in a 21-year-old male patient that was sufficiently treated by discontinuation of trigger agent application and dantrolene infusion. After surviving an MH episode diagnostic procedures are indicated to increase patient safety. In the presented case, the use of a novel minimal-invasive metabolic test with intramuscular injection of halothane and caffeine successfully confirmed MH susceptibility and hence might be an alternative for invasive in vitro contracture testing in selected cases.},
  language  = {en}
}
@article{RittnerHackelPflueckeetal.2013,
  author    = {Rittner, Heike Lydia and Hackel, Dagmar and Pfl{\"u}cke, Diana and Neumann, Annick and Viebahn, Johannes and Mousa, Shaaban and Wischmeyer, Erhard and Roewer, Norbert and Brack, Alexander},
  title     = {The Connection of Monocytes and Reactive Oxygen Species in Pain},
  series = {PLoS ONE},
  journal   = {PLoS ONE},
  doi       = {10.1371/journal.pone.0063564},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96669},
  year      = {2013},
  abstract  = {The interplay of specific leukocyte subpopulations, resident cells and proalgesic mediators results in pain in inflammation. Proalgesic mediators like reactive oxygen species (ROS) and downstream products elicit pain by stimulation of transient receptor potential (TRP) channels. The contribution of leukocyte subpopulations however is less clear. Local injection of neutrophilic chemokines elicits neutrophil recruitment but no hyperalgesia in rats. In meta-analyses the monocytic chemoattractant, CCL2 (monocyte chemoattractant protein-1; MCP-1), was identified as an important factor in the pathophysiology of human and animal pain. In this study, intraplantar injection of CCL2 elicited thermal and mechanical pain in Wistar but not in Dark Agouti (DA) rats, which lack p47phox, a part of the NADPH oxidase complex. Inflammatory hyperalgesia after complete Freund's adjuvant (CFA) as well as capsaicin-induced hyperalgesia and capsaicin-induced current flow in dorsal root ganglion neurons in DA were comparable to Wistar rats. Macrophages from DA expressed lower levels of CCR2 and thereby migrated less towards CCL2 and formed limited amounts of ROS in vitro and 4-hydroxynonenal (4-HNE) in the tissue in response to CCL2 compared to Wistar rats. Local adoptive transfer of peritoneal macrophages from Wistar but not from DA rats reconstituted CCL2-triggered hyperalgesia in leukocyte-depleted DA and Wistar rats. A pharmacological stimulator of ROS production (phytol) restored CCL2-induced hyperalgesia in vivo in DA rats. In Wistar rats, CCL2-induced hyperalgesia was completely blocked by superoxide dismutase (SOD), catalase or tempol. Likewise, inhibition of NADPH oxidase by apocynin reduced CCL2-elicited hyperalgesia but not CFA-induced inflammatory hyperalgesia. In summary, we provide a link between CCL2, CCR2 expression on macrophages, NADPH oxidase, ROS and the development CCL2-triggered hyperalgesia, which is different from CFA-induced hyperalgesia. The study further supports the impact of CCL2 and ROS as potential targets in pain therapy.},
  language  = {en}
}
@article{SchusterJohannsenMoegeleetal.2014,
  author    = {Schuster, Frank and Johannsen, Stephan and Moegele, Susanne and Metterlein, Thomas and Roewer, Norbert and Anetseder, Martin},
  title     = {The effect of succinylcholine on malignant hyperthermia events in susceptible swine},
  doi       = {10.1186/1471-2253-14-14},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-110302},
  year      = {2014},
  abstract  = {Background While the impact of volatile anaesthetics to induce malignant hyperthermia (MH) is abundantly clear, the role of succinylcholine still remains controversial. To evaluate the influence of succinylcholine on porcine MH events, the authors investigated the hemodynamic and metabolic responses in MH susceptible (MHS) and non-susceptible (MHN) swine following either succinylcholine or halothane application alone or a combination of both substances. Methods With approval of the local animal care committee 27 MHS and 30 MHN pigs were anaesthetized and mechanically ventilated. Fiberoptic probes for continuous PCO2 measurement were inserted into the femoral vein and the triceps muscle. Group A received succinylcholine 4 mg/kg, group B incremental doses of halothane (0.5, 1.0 vol\%) and group C succinylcholine and halothane simultaneously. Vital signs were recorded continuously. Results Prior to drug application measured values did not differ between MHS and MHN. While MHN pigs did not show relevant alterations, succinylcholine, halothane and the combination of both lead to significant hemodynamic and metabolic changes in MHS swine. Conclusions Hemodynamic and metabolic alterations following succinylcholine were similar to halothane in MHS pigs. The combination of both pharmacological agents potentiated the observed effects. According to these results succinylcholine acted as an independent and supportive factor during onset of an MH episode.},
  language  = {en}
}
@article{RittnerSauerHackeletal.2014,
  author    = {Rittner, Heike L. and Sauer, Reine-Solange and Hackel, Dagmar and Morschel, Laura and Sahlbach, Henrike and Wang, Ying and Mousa, Shaaban A. and Roewer, Norbert and Brack, Alexander},
  title     = {Toll like receptor (TLR)-4 as a regulator of peripheral endogenous opioid-mediated analgesia in inflammation},
  doi       = {10.1186/1744-8069-10-10},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-110193},
  year      = {2014},
  abstract  = {Background Leukocytes containing opioid peptides locally control inflammatory pain. In the early phase of complete Freund's adjuvant (CFA)-induced hind paw inflammation, formyl peptides (derived e.g. from Mycobacterium butyricum) trigger the release of opioid peptides from neutrophils contributing to tonic basal antinociception. In the later phase we hypothesized that toll-like-receptor-(TLR)-4 activation of monocytes/macrophages triggers opioid peptide release and thereby stimulates peripheral opioid-dependent antinociception. Results In Wistar rats with CFA hind paw inflammation in the later inflammatory phase (48-96 h) systemic leukocyte depletion by cyclophosphamide (CTX) or locally injected naloxone (NLX) further decreased mechanical and thermal nociceptive thresholds. In vitro β-endorphin (β-END) content increased during human monocyte differentiation as well as in anti-inflammatory CD14+CD16- or non-classical M2 macrophages. Monocytes expressing TLR4 dose-dependently released β-END after stimulation with lipopolysaccharide (LPS) dependent on intracellular calcium. Despite TLR4 expression proinflammatory M1 and anti-inflammatory M2 macrophages only secreted opioid peptides in response to ionomycin, a calcium ionophore. Intraplantar injection of LPS as a TLR4 agonist into the inflamed paw elicited an immediate opioid- and dose-dependent antinociception, which was blocked by TAK-242, a small-molecule inhibitor of TLR4, or by peripheral applied NLX. In the later phase LPS lowered mechanical and thermal nociceptive thresholds. Furthermore, local peripheral TLR4 blockade worsened thermal and mechanical nociceptive pain thresholds in CFA inflammation. Conclusion Endogenous opioids from monocytes/macrophages mediate endogenous antinociception in the late phase of inflammation. Peripheral TLR4 stimulation acts as a transient counter-regulatory mechanism for inflammatory pain in vivo, and increases the release of opioid peptides from monocytes in vitro. TLR4 antagonists as new treatments for sepsis and neuropathic pain might unexpectedly transiently enhance pain by impairing peripheral opioid analgesia.},
  language  = {en}
}
@article{SchickIsbaryStueberetal.2012,
  author    = {Schick, Martin Alexander and Isbary, Jobst Tobias and Stueber, Tanja and Brugger, Juergen and Stumpner, Jan and Schlegel, Nicolas and Roewer, Norbert and Eichelbroenner, Otto and Wunder, Christian},
  title     = {Effects of crystalloids and colloids on liver and intestine microcirculation and function in cecal ligation and puncture induced septic rodents},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-78151},
  year      = {2012},
  abstract  = {Background: Septic acute liver and intestinal failure is associated with a high mortality. We therefore investigated the influence of volume resuscitation with different crystalloid or colloid solutions on liver and intestine injury and microcirculation in septic rodents. Methods: Sepsis was induced by cecal ligation and puncture (CLP) in 77 male rats. Animals were treated with different crystalloids (NaCl 0.9\% (NaCl), Ringer's acetate (RA)) or colloids (Gelafundin 4\% (Gel), 6\% HES 130/0.4 (HES)). After 24 h animals were re-anesthetized and intestinal (n = 6/group) and liver microcirculation (n = 6/group) were obtained using intravital microscopy, as well as macrohemodynamic parameters were measured. Blood assays and organs were harvested to determine organ function and injury. Results: HES improved liver microcirculation, cardiac index and DO2-I, but significantly increased IL-1β, IL-6 and TNF-α levels and resulted in a mortality rate of 33\%. Gel infused animals revealed significant reduction of liver and intestine microcirculation with severe side effects on coagulation (significantly increased PTT and INR, decreased haemoglobin and platelet count). Furthermore Gel showed severe hypoglycemia, acidosis and significantly increased ALT and IL-6 with a lethality of 29\%. RA exhibited no derangements in liver microcirculation when compared to sham and HES. RA showed no intestinal microcirculation disturbance compared to sham, but significantly improved the number of intestinal capillaries with flow compared to HES. All RA treated animals survided and showed no severe side effects on coagulation, liver, macrohemodynamic or metabolic state. Conclusions: Gelatine 4\% revealed devastated hepatic and intestinal microcirculation and severe side effects in CLP induced septic rats, whereas the balanced crystalloid solution showed stabilization of macro- and microhemodynamics with improved survival. HES improved liver microcirculation, but exhibited significantly increased pro-inflammatory cytokine levels. Crystalloid infusion revealed best results in mortality and microcirculation, when compared with colloid infusion.},
  subject      = {Medizin},
  language  = {en}
}
@article{KredelMuellenbachJohannesetal.2011,
  author    = {Kredel, Markus and Muellenbach, Ralf and Johannes, Amelie and Brederlau, Joerg and Roewer, Norbert and Wunder, Christian},
  title     = {Hepatic effects of lung protective pressure controlled ventilation and a combination of high frequency oscillatory ventilation and extracorporeal lung assist in experimental lung injury},
  doi       = {10.12659/MSM.881974},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-70833},
  year      = {2011},
  abstract  = {Background: Ventilation with high positive end-expiratory pressure (PEEP) can lead to hepatic dysfunction. The aim of this study was to investigate the hepatic effects of strategies using high airway pressures either in pressure-controlled ventilation (PCV) or in high-frequency oscillatory ventilation (HFOV) combined with an arteriovenous extracorporeal lung assist (ECLA). Material/Methods: Pietrain pigs underwent induction of lung injury by saline lavage. Ventilation was continued for 24 hours either as PCV with tidal volumes of 6 ml/kg and PEEP 3 cmH2O above the lower inflection point of the pressure-volume curve or as HFOV (≥12 Hz) with a mean tracheal airway pressure 3 cmH2O above the lower inflection point combined with arteriovenous ECLA (HFOV+ECLA). Fluids and norepinephrine stabilized the circulation. The indocyanine green plasma disappearance rate, serum bilirubin, aspartate aminotransferase, alanine aminotransferase, γ-glutamyltransferase, alkaline phosphatase, glutamate dehydrogenase, lactate dehydrogenase and creatine kinase were determined repeatedly. Finally, liver neutrophils were counted and liver cell apoptosis was assessed by terminal deoxynucleotidyl transferase nick end labeling (TUNEL). Results: Aspartate aminotransferase increased in the PCV group about three-fold and in the HFOV+ECLA group five-fold (p\<0.001). Correspondingly, creatine kinase increased about two-fold and four-fold, respectively (p\<0.001). Lactate dehydrogenase was increased in the HFOV+ECLA group (p\<0.028). The number of neutrophils infiltrating the liver tissue and the apoptotic index were low. Conclusions: High airway pressure PCV and HFOV with ECLA in the treatment of lavage-induced lung injury in pigs did not cause liver dysfunction or damage. The detected elevation of enzymes might be of extrahepatic origin.},
  language  = {en}
}
@article{NeuhausSamwerKunzmannetal.2012,
  author    = {Neuhaus, Winfried and Samwer, Fabian and Kunzmann, Steffen and Muellenbach, Ralph and Wirth, Michael and Speer, Christian P. and Roewer, Norbert and F{\"o}rster, Carola},
  title     = {Lung endothelial cells strengthen, but brain endothelial cells weaken barrier properties of a human alveolar epithelium cell culture model},
  series = {Differentiation},
  volume    = {84},
  journal   = {Differentiation},
  number    = {4},
  doi       = {10.1016/j.diff.2012.08.006},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-90284},
  pages     = {294-304},
  year      = {2012},
  abstract  = {The blood-air barrier in the lung consists of the alveolar epithelium, the underlying capillary endothelium, their basement membranes and the interstitial space between the cell layers. Little is known about the interactions between the alveolar and the blood compartment. The aim of the present study was to gain first insights into the possible interplay between these two neighboured cell layers. We established an in vitro Transwell model of the alveolar epithelium based on human cell line H441 and investigated the influence of conditioned medium obtained from human lung endothelial cell line HPMEC-ST1.6R on the barrier properties of the H441 layers. As control for tissue specificity H441 layers were exposed to conditioned medium from human brain endothelial cell line hCMEC/D3. Addition of dexamethasone was necessary to obtain stable H441 cell layers. Moreover, dexamethasone increased expression of cell type I markers (caveolin-1, RAGE) and cell type II marker SP-B, whereas decreased the transepithelial electrical resistance (TEER) in a concentration dependent manner. Soluble factors obtained from the lung endothelial cell line increased the barrier significantly proven by TEER values and fluorescein permeability on the functional level and by the differential expression of tight junctional proteins on the molecular level. In contrast to this, soluble factors derived from brain endothelial cells weakened the barrier significantly. In conclusion, soluble factors from lung endothelial cells can strengthen the alveolar epithelium barrier in vitro, which suggests communication between endothelial and epithelial cells regulating the integrity of the blood-air barrier.},
  language  = {en}
}
@article{SchusterJohannsenSchneiderbangeretal.2013,
  author    = {Schuster, Frank and Johannsen, Stephan and Schneiderbanger, Daniel and Roewer, Norbert},
  title     = {Evaluation of suspected malignant hyperthermia events during anesthesia},
  series = {BMC Anesthesiology},
  journal   = {BMC Anesthesiology},
  doi       = {10.1186/1471-2253-13-24},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-96231},
  year      = {2013},
  abstract  = {Background Malignant hyperthermia (MH), a metabolic myopathy triggered by volatile anesthetics and depolarizing muscle relaxants, is a potentially lethal complication of general anesthesia in susceptible patients. The implementation of modern inhalation anesthetics that research indicates as less potent trigger substances and the recommended limitations of succinylcholine use, suggests there may be considerable decline of fulminant MH cases. In the presented study, the authors analyzed suspected MH episodes during general anesthesia of patients that were referred to the Wuerzburg MH unit between 2007 and 2011, assuming that MH is still a relevant anesthetic problem in our days. Methods With approval of the local ethics committee data of patients that underwent muscle biopsy and in vitro contracture test (IVCT) between 2007 and 2011 were analyzed. Only patients with a history of suspected MH crisis were included in the study. The incidents were evaluated retrospectively using anesthetic documentation and medical records. Results Between 2007 and 2011 a total of 124 patients were tested. 19 of them were referred because of suspected MH events; 7 patients were diagnosed MH-susceptible, 4 MH-equivocal and 8 MH-non-susceptible by IVCT. In a majority of cases masseter spasm after succinylcholine had been the primary symptom. Cardiac arrhythmias and hypercapnia frequently occurred early in the course of events. Interestingly, dantrolene treatment was initiated in a few cases only. Conclusions MH is still an important anesthetic complication. Every anesthetist must be aware of this life-threatening syndrome at any time. The rapid onset of adequate therapy is crucial to avoid major harm and possibly lethal outcome. Dantrolene must be readily available wherever MH triggering agents are used for anesthesia.},
  language  = {en}
}
@article{ShityakovPuskasPapaietal.2015,
  author    = {Shityakov, Sergey and Pusk{\´a}s, Istv{\´a}n and P{\´a}pai, Katalin and Salvador, Ellaine and Roewer, Norbert and F{\"o}rster, Carola and Broscheit, Jens-Albert},
  title     = {Sevoflurane-sulfobutylether-\(\beta\)-cyclodextrin complex: preparation, characterization, cellular toxicity, molecular modeling and blood-brain barrier transport studies},
  series = {Molecules},
  volume    = {20},
  journal   = {Molecules},
  doi       = {10.3390/molecules200610264},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-148543},
  pages     = {10264-10279},
  year      = {2015},
  abstract  = {The objective of the present investigation was to study the ability of sulfobutylether-\(\beta\)-cyclodextrin (SBECD) to form an inclusion complex with sevoflurane (SEV), a volatile anesthetic with poor water solubility. The inclusion complex was prepared, characterized and its cellular toxicity and blood-brain barrier (BBB) permeation potential of the formulated SEV have also been examined for the purpose of controlled drug delivery. The SEV-SBE\(\beta\)CD complex was nontoxic to the primary brain microvascular endothelial (pEND) cells at a clinically relevant concentration of sevoflurane. The inclusion complex exhibited significantly higher BBB permeation profiles as compared with the reference substance (propranolol) concerning calculated apparent permeability values (P\(_{app}\)). In addition, SEV binding affinity to SBE\(\beta\)CD was confirmed by a minimal Gibbs free energy of binding (ΔG\(_{bind}\)) value of -1.727 ± 0.042 kcal・mol\(^{-1}\) and an average binding constant (K\(_{b}\)) of 53.66 ± 9.24 mM indicating rapid drug liberation from the cyclodextrin amphiphilic cavity.},
  language  = {en}
}