@article{CurtazSchmittHerbertetal.2020, author = {Curtaz, Carolin J. and Schmitt, Constanze and Herbert, Saskia-Laureen and Feldheim, Jonas and Schlegel, Nicolas and Gosselet, Fabien and Hagemann, Carsten and Roewer, Norbert and Meybohm, Patrick and W{\"o}ckel, Achim and Burek, Malgorzata}, title = {Serum-derived factors of breast cancer patients with brain metastases alter permeability of a human blood-brain barrier model}, series = {Fluids and Barriers of the CNS}, volume = {17}, journal = {Fluids and Barriers of the CNS}, doi = {10.1186/s12987-020-00192-6}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-229940}, year = {2020}, abstract = {Background The most threatening metastases in breast cancer are brain metastases, which correlate with a very poor overall survival, but also a limited quality of life. A key event for the metastatic progression of breast cancer into the brain is the migration of cancer cells across the blood-brain barrier (BBB). Methods We adapted and validated the CD34\(^+\) cells-derived human in vitro BBB model (brain-like endothelial cells, BLECs) to analyse the effects of patient serum on BBB properties. We collected serum samples from healthy donors, breast cancer patients with primary cancer, and breast cancer patients with, bone, visceral or cerebral metastases. We analysed cytokine levels in these sera utilizing immunoassays and correlated them with clinical data. We used paracellular permeability measurements, immunofluorescence staining, Western blot and mRNA analysis to examine the effects of patient sera on the properties of BBB in vitro. Results The BLECs cultured together with brain pericytes in transwells developed a tight monolayer with a correct localization of claudin-5 at the tight junctions (TJ). Several BBB marker proteins such as the TJ proteins claudin-5 and occludin, the glucose transporter GLUT-1 or the efflux pumps PG-P and BCRP were upregulated in these cultures. This was accompanied by a reduced paracellular permeability for fluorescein (400 Da). We then used this model for the treatment with the patient sera. Only the sera of breast cancer patients with cerebral metastases had significantly increased levels of the cytokines fractalkine (CX3CL1) and BCA-1 (CXCL13). The increased levels of fractalkine were associated with the estrogen/progesterone receptor status of the tumour. The treatment of BLECs with these sera selectively increased the expression of CXCL13 and TJ protein occludin. In addition, the permeability of fluorescein was increased after serum treatment. Conclusion We demonstrate that the CD34\(^+\) cell-derived human in vitro BBB model can be used as a tool to study the molecular mechanisms underlying cerebrovascular pathologies. We showed that serum from patients with cerebral metastases may affect the integrity of the BBB in vitro, associated with elevated concentrations of specific cytokines such as CX3CL1 and CXCL13.}, language = {en} } @article{BauerOpitzFilseretal.2019, author = {Bauer, Maria and Opitz, Anne and Filser, J{\"o}rg and Jansen, Hendrik and Meffert, Rainer H. and Germer, Christoph T. and Roewer, Norbert and Muellenbach, Ralf M. and Kredel, Markus}, title = {Perioperative redistribution of regional ventilation and pulmonary function: a prospective observational study in two cohorts of patients at risk for postoperative pulmonary complications}, series = {BMC Anesthesiology}, volume = {19}, journal = {BMC Anesthesiology}, doi = {10.1186/s12871-019-0805-8}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-200730}, pages = {132}, year = {2019}, abstract = {Background Postoperative pulmonary complications (PPCs) increase morbidity and mortality of surgical patients, duration of hospital stay and costs. Postoperative atelectasis of dorsal lung regions as a common PPC has been described before, but its clinical relevance is insufficiently examined. Pulmonary electrical impedance tomography (EIT) enables the bedside visualization of regional ventilation in real-time within a transversal section of the lung. Dorsal atelectasis or effusions might cause a ventral redistribution of ventilation. We hypothesized the existence of ventral redistribution in spontaneously breathing patients during their recovery from abdominal and peripheral surgery and that vital capacity is reduced if regional ventilation shifts to ventral lung regions. Methods This prospective observational study included 69 adult patients undergoing elective surgery with an expected intermediate or high risk for PPCs. Patients undergoing abdominal and peripheral surgery were recruited to obtain groups of equal size. Patients received general anesthesia with and without additional regional anesthesia. On the preoperative, the first and the third postoperative day, EIT was performed at rest and during spirometry (forced breathing). The center of ventilation in dorso-ventral direction (COVy) was calculated. Results Both groups received intraoperative low tidal volume ventilation. Postoperative ventral redistribution of ventilation (forced breathing COVy; preoperative: 16.5 (16.0-17.3); first day: 17.8 (16.9-18.2), p < 0.004; third day: 17.4 (16.2-18.2), p = 0.020) and decreased forced vital capacity in percentage of predicted values (FVC\%predicted) (median: 93, 58, 64\%, respectively) persisted after abdominal surgery. In addition, dorsal to ventral shift was associated with a decrease of the FVC\%predicted on the third postoperative day (r = - 0.66; p < 0.001). A redistribution of pulmonary ventilation was not observed after peripheral surgery. FVC\%predicted was only decreased on the first postoperative day (median FVC\%predicted on the preoperative, first and third day: 85, 81 and 88\%, respectively). In ten patients occurred pulmonary complications after abdominal surgery also in two patients after peripheral surgery. Conclusions After abdominal surgery ventral redistribution of ventilation persisted up to the third postoperative day and was associated with decreased vital capacity. The peripheral surgery group showed only minor changes in vital capacity, suggesting a role of the location of surgery for postoperative redistribution of pulmonary ventilation.}, language = {en} } @article{WollbornWunderStixetal.2015, author = {Wollborn, Jakob and Wunder, Christian and Stix, Jana and Neuhaus, Winfried and Bruno, Rapahel R. and Baar, Wolfgang and Flemming, Sven and Roewer, Norbert and Schlegel, Nicolas and Schick, Martin A.}, title = {Phosphodiesterase-4 inhibition with rolipram attenuates hepatocellular injury in hyperinflammation in vivo and in vitro without influencing inflammation and HO-1 expression}, series = {Journal of Pharmacology and Pharmacotherapeutics}, volume = {6}, journal = {Journal of Pharmacology and Pharmacotherapeutics}, number = {1}, doi = {10.4103/0976-500X.149138}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-149336}, pages = {13-23}, year = {2015}, abstract = {Objective: To investigate the impact of the phophodiesterase-4 inhibition (PD-4-I) with rolipram on hepatic integrity in lipopolysaccharide (LPS) induced hyperinflammation. Materials and Methods: Liver microcirculation in rats was obtained using intravital microscopy. Macrohemodynamic parameters, blood assays, and organs were harvested to determine organ function and injury. Hyperinflammation was induced by LPS and PD-4-I rolipram was administered intravenously one hour after LPS application. Cell viability of HepG2 cells was measured by EZ4U-kit based on the dye XTT. Experiments were carried out assessing the influence of different concentrations of tumor necrosis factor alpha (TNF-α) and LPS with or without PD-4-I. Results: Untreated LPS-induced rats showed significantly decreased liver microcirculation and increased hepatic cell death, whereas LPS + PD-4-I treatment could improve hepatic volumetric flow and cell death to control level whithout influencing the inflammatory impact. In HepG2 cells TNF-α and LPS significantly reduced cell viability. Coincubation with PD-4-I increased HepG2 viability to control levels. The heme oxygenase 1 (HO-1) pathway did not induce the protective effect of PD-4-I. Conclusion: Intravenous PD-4-I treatment was effective in improving hepatic microcirculation and hepatic integrity, while it had a direct protective effect on HepG2 viability during inflammation.}, language = {en} } @article{KredelKunzmannSchlegeletal.2017, author = {Kredel, Markus and Kunzmann, Steffen and Schlegel, Paul-Gerhardt and W{\"o}lfl, Matthias and Nordbeck, Peter and B{\"u}hler, Christoph and Lotz, Christopher and Lepper, Philipp M. and Wirbelauer, Johannes and Roewer, Norbert and Muellenbach, Ralf M.}, title = {Double Peripheral Venous and Arterial Cannulation for Extracorporeal Membrane Oxygenation in Combined Septic and Cardiogenic Shock}, series = {American Journal of Case Reports}, volume = {18}, journal = {American Journal of Case Reports}, doi = {10.12659/AJCR.902485}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-158193}, pages = {723-727}, year = {2017}, abstract = {Background: The use of venoarterial extracorporeal membrane oxygenation (va-ECMO) via peripheral cannulation for septic shock is limited by blood flow and increased afterload for the left ventricle. Case Report: A 15-year-old girl with acute myelogenous leukemia, suffering from severe septic and cardiogenic shock, was treated by venoarterial extracorporeal membrane oxygenation (va-ECMO). Sufficient extracorporeal blood flow matching the required oxygen demand could only be achieved by peripheral cannulation of both femoral arteries. Venous drainage was performed with a bicaval cannula inserted via the left V. femoralis. To accomplish left ventricular unloading, an additional drainage cannula was placed in the left atrium via percutaneous atrioseptostomy (va-va-ECMO). Cardiac function recovered and the girl was weaned from the ECMO on day 6. Successful allogenic stem cell transplantation took place 2 months later. Conclusions: In patients with vasoplegic septic shock and impaired cardiac contractility, double peripheral venoarterial extracorporeal membrane oxygenation (va-va-ECMO) with transseptal left atrial venting can by a lifesaving option.}, language = {en} } @article{SchickBaarBrunoetal.2015, author = {Schick, Martin Alexander and Baar, Wolfgang and Bruno, Raphael Romano and Wollborn, Jakob and Held, Christopher and Schneider, Reinhard and Flemming, Sven and Schlegel, Nicolas and Roewer, Norbert and Neuhaus, Winfried and Wunder, Christian}, title = {Balanced hydroxyethylstarch (HES 130/0.4) impairs kidney function in-vivo without inflammation}, series = {PLoS One}, volume = {10}, journal = {PLoS One}, number = {9}, doi = {10.1371/journal.pone.0137247}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-126068}, pages = {e0137247}, year = {2015}, abstract = {Volume therapy is a standard procedure in daily perioperative care, and there is an ongoing discussion about the benefits of colloid resuscitation with hydroxyethylstarch (HES). In sepsis HES should be avoided due to a higher risk for acute kidney injury (AKI). Results of the usage of HES in patients without sepsis are controversial. Therefore we conducted an animal study to evaluate the impact of 6\% HES 130/0.4 on kidney integrity with sepsis or under healthy conditions Sepsis was induced by standardized Colon Ascendens Stent Peritonitis (sCASP). sCASP-group as well as control group (C) remained untreated for 24 h. After 18 h sCASP+HES group (sCASP+VOL) and control+HES (C+VOL) received 50 ml/KG balanced 6\% HES (VOL) 130/0.4 over 6h. After 24h kidney function was measured via Inulin- and PAH-Clearance in re-anesthetized rats, and serum urea, creatinine (crea), cystatin C and Neutrophil gelatinase-associated lipocalin (NGAL) as well as histopathology were analysed. In vitro human proximal tubule cells (PTC) were cultured +/- lipopolysaccharid (LPS) and with 0.1-4.0\% VOL. Cell viability was measured with XTT-, cell toxicity with LDH-test. sCASP induced severe septic AKI demonstrated divergent results regarding renal function by clearance or creatinine measure focusing on VOL. Soleley HES (C+VOL) deteriorated renal function without sCASP. Histopathology revealed significantly derangements in all HES groups compared to control. In vitro LPS did not worsen the HES induced reduction of cell viability in PTC cells. For the first time, we demonstrated, that application of 50 ml/KG 6\% HES 130/0.4 over 6 hours induced AKI without inflammation in vivo. Severity of sCASP induced septic AKI might be no longer susceptible to the way of volume expansion}, language = {en} } @article{SchickBaarFlemmingetal.2014, author = {Schick, Martin A. and Baar, Wolfgang and Flemming, Sven and Schlegel, Nicolas and Wollborn, Jakob and Held, Christopher and Schneider, Reinhard and Brock, Robert W. and Roewer, Norbert and Wunder, Christian}, title = {Sepsis-induced acute kidney injury by standardized colon ascendens stent peritonitis in rats - a simple, reproducible animal model}, series = {Intensive Care Medicine Experimental}, volume = {2}, journal = {Intensive Care Medicine Experimental}, number = {34}, doi = {10.1186/s40635-014-0034-x}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-126111}, year = {2014}, abstract = {Background Up to 50\% of septic patients develop acute kidney injury (AKI). The pathomechanism of septic AKI is poorly understood. Therefore, we established an innovative rodent model to characterize sepsis-induced AKI by standardized colon ascendens stent peritonitis (sCASP). The model has a standardized focus of infection, an intensive care set up with monitoring of haemodynamics and oxygenation resulting in predictable impairment of renal function, AKI parameters as well as histopathology scoring. Methods Anaesthetized rats underwent the sCASP procedure, whereas sham animals were sham operated and control animals were just monitored invasively. Haemodynamic variables and blood gases were continuously measured. After 24 h, animals were reanesthetized; cardiac output (CO), inulin and PAH clearances were measured and later on kidneys were harvested; and creatinine, urea, cystatin C and neutrophil gelatinase-associated lipocalin (NGAL) were analysed. Additional sCASP-treated animals were investigated after 3 and 9 days. Results All sCASP-treated animals survived, whilst ubiquitous peritonitis and significantly deteriorated clinical and macrohaemodynamic sepsis signs after 24 h (MAP, CO, heart rate) were obvious. Blood analyses showed increased lactate and IL-6 levels as well as leucopenia. Urine output, inulin and PAH clearance were significantly decreased in sCASP compared to sham and control. Additionally, significant increase in cystatin C and NGAL was detected. Standard parameters like serum creatinine and urea were elevated and sCASP-induced sepsis increased significantly in a time-dependent manner. The renal histopathological score of sCASP-treated animals deteriorated after 3 and 9 days. Conclusions The presented sCASP method is a standardized, reliable and reproducible method to induce septic AKI. The intensive care set up, continuous macrohaemodynamic and gas exchange monitoring, low mortality rate as well as the opportunity of detailed analyses of kidney function and impairments are advantages of this setup. Thus, our described method may serve as a new standard for experimental investigations of septic AKI.}, language = {en} }