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Background: The complement and kallikrein-kinin systems (KKS) are activated during vascular inflammation. The aim of this study was to investigate if blockade of the KKS can affect complement activation on the endothelium during inflammation. Methods: Complement deposition on endothelial microvesicles was assayed in vasculitis patient plasma samples and controls. Plasma was perfused over glomerular endothelial cells and complement deposition assayed by flow cytometry. The effect of the kinin system was assessed using kinin receptor antagonists and C1-inhibitor. The in vivo effect was assessed in kidney sections from mice with nephrotoxic serum-induced glomerulonephritis treated with a kinin receptor antagonist. Findings: Vasculitis patient plasma had significantly more C3- and C9-positive endothelial microvesicles than controls. Perfusion of patient acute-phase plasma samples over glomerular endothelial cells induced the release of significantly more complement-positive microvesicles, in comparison to remission or control plasma. Complement activation on endothelial microvesicles was reduced by kinin B1- and B2-receptor antagonists or by C1-inhibitor (the main inhibitor of the classical pathway and the KKS). Likewise, perfusion of glomerular endothelial cells with C1-inhibitor-depleted plasma induced the release of complement-positive microvesicles, which was significantly reduced by kinin-receptor antagonists or C1-inhibitor. Mice with nephrotoxic serum-induced glomerulonephritis exhibited significantly reduced glomerular C3 deposition when treated with a B1-receptor antagonist. Interpretation: Excessive complement deposition on the endothelium will promote endothelial injury and the release of endothelial microvesicles. This study demonstrates that blockade of the KKS can reduce complement activation and thereby the inflammatory response on the endothelium. (C) 2019 The Authors. Published by Elsevier B.V. Funding Agencies|Swedish Research CouncilSwedish Research Council [K2015-99X-22877-01-6, 2017-01920]; Knut and Alice Wallenberg FoundationKnut & Alice Wallenberg Foundation [2015.0320]; Torsten Soderberg Foundation; Skane Centre of Excellence in Health; Crown Princess Lovisas Society for Child Care; Konung Gustaf V:s 80-arsfond; Alfred Osterlund Foundation; Wallenberg Center for Molecular Medicine; Swedish Rheumatism Association; Anna-Greta Crafoord Foundation; Greta and Johan Kocks Foundation; Samariten Foundation; Fanny Ekdahl foundation; Jerring foundation; Fondation pour la Recherche MedicaleFondation pour la Recherche Medicale [DEQ20170336759]; Ingrid Asp Foundation; IngaBritt och Arne Lundbergs Research Foundation; Region Skane; Thelma Zoegas Foundation

In dieser Arbeit werden Absorber hinsichtlich ihrer akustischen Eigenschaften charakterisiert. Akustische Absorber werden zur Reduktion von L��rm eingesetzt. Solche akustischen Absorber k��nnen durch eine Vielzahl von Konzepten realisiert werden. Einerseits existieren aktive Ma��nahmen, um L��rm mit Hilfe von elektro��akustischen Methoden zu reduzieren. Auf der anderen Seite stellen passive und damit energieautarke Absorber eine meist kosteng��nstigere und robustere Alternative zu aktiven Absorbern dar. Passive Absorber k��nnen durch resonante Strukturen, beispielsweise ausgef��hrt als Helmholtz��Resonator, realisiert werden. Alternativ dazu k��nnen sie auch aus por��sem Materialbestehen. Herk��mmliche por��se Absorber werden haupts��chlich zur Vermeidung von L��rm im Bereich ab ungef��hr 1 kHz verwendet. Hierbei wird die akustische Energie mittels Reibung in W��rme umgesetzt. Ein wichtiges Werkzeug zur akustischen Charakterisierung stellen Intensit��tssonden dar. Durch Intensit��tssonden kann mit Hilfe eines Schalldruckmikrofons und einem 3D-Schallschnellesensor der akustische Energiefluss bestimmt werden. In dieser Arbeit wird auf diese Weise das Einf��gungsd��mmma�� von akustischen Absorbern untersucht. Weiterhin wird eine neuartige, simulationsgest��tzte Kalibrierungsmethode entwickelt, um alle drei Komponenten des Schallschnellesensors simultan mit Hilfe eines Referenzschallfeldes zu kalibrieren. Dieses Referenzschallfeld wird von einem schwingendem Kolben erzeugt und mittels numerischer Methoden analysiert. Die entstandene Kalibrierungsmethode wird charakterisiert und eine Validierung der Methode pr��sentiert. Von ��u��erster Wichtigkeit ist die Bestimmung des Absorptionsverhaltens von passiven Absorbern als Funktion des Schalleinfallswinkels. Hierzu werden zwei bestehende Methoden implementiert und entsprechend weiterentwickelt. Das erste Verfahren ist eine Subtraktionsmethode im Zeitbereich. Hier werden die Materialeigenschaften durch die Trennung eines einfallenden und reflektierenden Impulses berechnet. Der zweiten Methode liegt die ��rtliche Fourier Transformation zu Grunde. Im Zuge dessen werden die akustischen Materialeigenschaften durch die Zerlegung des Schallfelds in ebene Wellenkomponenten auf verschiedenen Messebenen bestimmt. Beide Verfahren werden untersucht und Verbesserungen der Methoden vorgestellt. Passive akustische Absorber werden hinsichtlich ihrer akustischen Eigenschaften unter schr��gem Schalleinfall charakterisiert und Aussagen ��ber das Absorptionsverhalten abgeleitet. Diese Materialcharakterisierungen stellen einen wichtigen Baustein dar, um ein Verst��ndnis daf��r zu entwickeln, an welcher Stelle Absorber platziert werden m��ssen, um akustische Energie effizient absorbieren zu k��nnen. Dar��ber hinaus k��nnen die Materialdaten als Randbedingung f��r pr��zise Simulationen realistischer Schallfelder verwendet werden. Abschlie��end wird die Entwicklung und Charakterisierung eines akustischen Absorbers f��r niedrige Frequenzen pr��sentiert. Durch Anwendung einer massebeladenen Membran kann akustische Energie schmalbandig in mechanische Energie umgewandelt werden, wobei die jeweilige Schwingungsform des Systems einen akustischen Kurzschluss zur Folge hat. Daraus ergibt sich eine ineffiziente Schallabstrahlung dieser mechanischen Energie einhergehend mit einem hohen Durchgangsd��mmma�� des Absorbers. Der passive mechanische Absorber wird charakterisiert und eine Anwendung als Absorberarray zur Absorption schmalbandigen L��rms im Frequenzbereich unter 300Hz besprochen., The focus of this thesis is the characterization of acoustic absorbers. Acoustic absorbers are employed to reduce noise and can be realized by means of numerous concepts. Active strategies aim to reduce noise by employing electro��acoustical approaches while passive absorbers present a more cost��efficient and robust alternative. Passive absorbers can be realized by either using resonant structures such as Helmholtz resonators or can be made from porous materials. Traditional porous absorbers are most commonly used for the reduction of noise with frequency components higher than 1 kHz. In porous absorbers, the acoustic energy is transformed into thermal energy by means of friction. Acoustic intensity probes are crucial tools for acoustic characterization. They consist of a sound pressure microphone and a 3D particle velocity sensor and enable determining the acoustic energy flow. In this thesis, the sound insertion loss of acoustic absorbers is analyzed by means of an acoustic intensity probe. Furthermore, a novel simulation aided calibration method is developed to calibrate all three components of the particle velocity sensor simultaneously by means of a reference sound field. The reference sound field, produced by a moving piston, is investigated by applying numerical calculation methods. The calibration method is then characterized and a validation of the method presented. In addition to this, two existing measurement methods for characterizing passive acoustic absorber materials under oblique angle of sound incidence are implemented and further improved. The first approach employs subtraction in the time domain, which allows for calculating the properties by separating an incoming and a reflecting impulse. The second method is based on a spatial Fourier transform. Here, the acoustic properties are calculated by decomposition of a sound field into plane wave components on several measurement planes. Both methods are characterized and subsequently improved. A characterization of passive acoustic absorbers in terms of the acoustic properties at oblique angles of sound incidence is performed and the absorption capability of the absorbers identified. The characterization is essential to gain the necessary understanding of where to place which absorber to achieve the optimum absorption of acoustic energy. Moreover, the material data can be used as boundary conditions for a precise simulation of realistic acoustic fields. Finally, development and characterization of an acoustic absorber for low frequencies is discussed. By applying a mass loaded membrane, acoustic energy can be transformed narrow-bandedly into mechanical energy, which produces an acoustic short circuit. As a consequence, the mechanical energy is not emitted efficiently in the free field, which results in a high sound transmission loss. The passive mechanical absorber is characterized and its application as an absorber array for absorbing narrow band acoustic energy in a frequency range below 300Hz presented.

Sequence information for the 20 urinary peptides included in the AKI peptide marker pattern. (PDF 10804 kb)

Background Reliable and timely detection of acute rejection in renal transplant patients is important to preserve the allograft function and to prevent premature allograft failure. The current gold standard for the rejection diagnosis is an allograft biopsy which is usually performed upon an unexplained decline in allograft function. Because of the invasiveness of the biopsy, non-invasive tests have been suggested to diagnose acute rejection including mass spectrometry analysis of urine samples. Design and methods The aim of this study is to examine the diagnostic accuracy of mass spectrometry analysis in urine for the diagnosis of acute rejections using the biopsy as gold-standard. The study is an ongoing prospective, single-arm, multicentre, phase 3 diagnostic accuracy study. It started in October 2011 and will be concluded in December 2015. Patient within the first year after transplantation who are scheduled for a biopsy to clarify unexplained impairment of the allograft are consecutively recruited into the study. The overall sample size (n = 600) was calculated to demonstrate a sensitivity of 83 % and a specificity of 70 % for a one-sided type one error of 2.5 % and a power of 80 % per hypothesis. Biopsy evaluation and mass spectrometry analysis of urine samples (obtained immediately before biopsy) are performed independently by different readers without knowledge from the respective other assessment. The follow-up observation period is 6 months. For the primary analysis, the lower limits of the two-sided 95 % Wald confidence intervals for sensitivity and specificity will be compared with the pre-specified thresholds (83 % for sensitivity and 70 % for specificity). In secondary analyses the predictive values, the diagnostic measures in subgroups, and the clinical course will be assessed. Discussion Previous phase 2 diagnostic accuracy studies (in small selected study populations) provided sufficient evidence to suggest mass spectrometry on urine samples as a promising approach to detect acute rejections. This study determines the diagnostic performance of the test in the routine setting of post-transplant patient care, compared to the biopsy-based rejection diagnosis. The next step would be a randomized trial to compare the two diagnostic strategies (including the urine test or not) in relation to patient relevant endpoints. Trial registration NCT01315067 ; March 14, 2011 peerReviewed

Quality Assurance/Monitoring. (DOC 31 kb)

The study focused on the induction of a T helper cell response against the tumor-associated antigen HER2/neu being commonly overexpressed in breast and ovarian tumors. For this purpose, the extracellular domain of the receptor tyrosine kinase was produced in CHO cells and purified in a two-step FPLC column procedure. The protein antigen was loaded on monocyte-derived dendritic cells to generate highly potent antigen presenting cells for the stimulation of autologous naive CD4+ T lymphocytes in an in vitro priming system. IFN-γ secreting cells were detected as soon as 2 weeks after initiation of DC-T cell microcultures. Unequivocal HER2/neu specificity, however, could only be demonstrated in one T cell line. Due to its CD4/CD8 double positive phenotype, there was strong evidence for clonal selection of a potentially autoreactive T cell, that escaped negative thymic selection. After isolation of the descendant T cell clone F2.5 the potential of these HER2/neu-reactive cells to differentiate to either CD4 or CD8 single positive T cells was demonstrated and found to be dependent on stimulation and growth conditions. Ziel der Arbeit war der Aufbau einer Methode zur Induktion einer T-Helferzellantwort gegen das tumorassoziierte Antigen HER2/neu. Hierzu wurde die extrazelluläre Domäne dieses vor allem beim Mammakarzinom überexprimierten Rezeptors in CHO-Zellen gentechnisch produziert und chromatographisch aufgereinigt. Mit dem Protein wurden Monozyten-abgeleitete dendritische Zellen beladen und diese zur Vakzinierung autologer CD4+ T-Zellen eingesetzt. Durch Expansion in Mikrokulturen wurden IFN-γ produzierende T-Helferzellen schon nach 2 Wochen identifiziert. Eine HER2/neu-Spezifität bestätigte sich jedoch nur bei T-Zellen einer Kultur. Wegen ihres CD4/CD8 doppelt-positiven Phänotyps wurde gefolgert, dass es sich um Nachkommen einer unreifen T-Zelle handelt, die der negativen Selektion im Thymus entging. Mit Hilfe des abgeleiteten T-Zellklons F2.5 wurde das Potential der Zellen aufgezeigt, sich abhängig von den Stimulationsbedingungen in CD4 oder CD8 einfach-positive T-Zellen zu differenzieren.