436 research outputs found
Einfluss von NO-Donoren und NO-Donor-Produgs auf die PermeabilitÀt eines Modells der Blut-Hirn-Schranke aus primÀren Schweinehirnendothelzellen
Ziel der Promotionsarbeit:
Im Rahmen des Projektes "Entdeckung und Entwicklung von neuartigen Wirkstoffen und TrĂ€gersystemen fĂŒr die Pharmakotherapie der Alzheimer-Demenz" der pharmazeutischen Institute der Friedrich-Schiller-UniversitĂ€t Jena wurde ein Modell benötigt, dass die Blut-Hirn-Schranke simuliert, so dass daran neue Substanzen auf ihre Eigenschaften getestet werden können. Dieses Modell soll Aussagen zur PenetrationsfĂ€higkeit von Substanzen ermöglichen. Des weiteren ist mit einem Modell aus Endothelzellen die Untersuchung von EinflĂŒssen neuer Substanzen auf die Dichtigkeit der Monolayer möglich. An diesem Modell sollen die EinflĂŒsse der unterschiedlichen NO-Donoren und NO-Donor-Prodrugs auf die Dichtigkeit der Endothelzellmonolayer untersucht werden.
DurchfĂŒhrung:
Gemessen wurde der Fluss von Carboxyfluorescein ĂŒber einen Endothelzellmonolayer aus primĂ€ren Schweinehirnendothelzellen. Dieser Monolayer wurde mit NO-Donoren, NO-Donor- Prodrugs oder einer Kombination aus NO-Donoren und Methylenblau oder NO-Donor- Prodrugs und Methylenblau behandelt und der dadurch beeinflusste Fluss von Carboxyfluorescein gemessen
Mathematikbezogene Beliefs fachfremd unterrichtender Lehrerinnen und Lehrer zu Beginn einer QualifizierungsmaĂnahme
Fachfremd unterrichtende Lehrpersonen rĂŒcken verstĂ€rkt in den Blick mathematikdidaktischer
Forschung: fachfremd erteilter Unterricht ist weniger
kognitiv aktivierend (Baumert et al., 2010) und wirkt sich negativ auf
SchĂŒlerleistungen aus (Richter, Kuhl, Haag & Pant, 2013). Neben Professionswissen
haben Ăberzeugungen einen entscheidenden Einfluss auf die
Planung und Gestaltung von Unterricht (vgl. Törner, Rolka, Roesken &
Sriraman, 2010). Im Rahmen der Begleitforschung zu einer vom DZLM
(www.dzlm.de) getragenen Qualifizierung fĂŒr fachfremd unterrichtende
Lehrpersonen (LĂŒnne & Biehler, 2015) untersuchten wir zu Beginn der
MaĂnahme die Einstellungen und Ăberzeugungen Fachfremder zum Lehren
und Lernen von Mathematik. Der Fokus dieses Beitrages liegt auf der
Beschreibung der Erhebungsinstrumente und erster Ergebnisse
Wirkungsanalyse zu den Gestaltungsprinzipien von Multiplikatoren-Fortbildungen des DZLM
Das Deutsche Zentrum fĂŒr Lehrerbildung Mathematik (DZLM) setzt in seinen Fortbildungsangeboten den Fokus auf die kontinuierliche, professionelle Entwicklung von Multiplikatoren und Multiplikatorinnen (MuM). Aus der Forschungsperspektive des DZLM liegt das erhebliche Potenzial in der Arbeit mit MuM in deren mehrdimensionaler Rollen- und Aufgabenstruktur begrĂŒndet. Auf der einen Seite verfĂŒgen die MuM ĂŒber reichhaltige Erfahrungen und Expertise zu Unterrichtsprozessen aus der eigenen LehrtĂ€tigkeit. Auf der anderen Seite arbeiten sie in erwachsenendidaktischen Wirkungsfeldern und eröffnen einen unmittelbaren Zugang zur Kompetenzentwicklung von Lehrerinnen und Lehrern. Vor diesem Hintergrund fokussiert dieser Beitrag die folgenden Fragen: Welche Kompetenzentwicklung lĂ€sst sich aus Sicht der MuM nach Teilnahme an einer Qualifizierung feststellen? Inwieweit beziehen sich praktisch arbeitende MuM in ihren Vorstellungen zur Fortbildungsgestaltung auf die theoretisch fundierten DZLM-Prinzipien
Microscopic and Molecular Characterization of the Prehaustorial Resistance against Wheat Leaf Rust (Puccinia triticina) in Einkorn (Triticum monococcum)
Puccinia triticina f. sp. tritici (Eriks.), the causal agent of leaf rust, causes substantial yield losses in wheat production. In wheat many major leaf rust resistance genes have been overcome by virulent races. In contrast, the prehaustorial resistance (phr) against wheat leaf rust detected in the diploid wheat Einkorn (Triticum monoccocum var. monococcum) accession PI272560 confers race-independent resistance against isolates virulent on accessions harbouring resistance genes located on the A-genome of Triticum aestivum. Phr in PI272560 leads to abortion of fungal development during the formation of haustorial mother cells and to increased hydrogen peroxide concentration in comparison to the susceptible accession 36554 (Triticum boeoticum ssp. thaoudar var. reuteri). Increased peroxidase and endochitinase activity was detected in PI272560 within 6 hours after inoculation (hai). Comparative transcriptome profiling using Massive Analysis of cDNA Ends (MACE) in infected and non-infected leaves detected 14220 differentially expressed tags in PI272560 and 15472 in accession 36554. Of these 2908 and 3004, respectively, could be assigned to Gene Ontology (GO) categories of which 463 were detected in both accessions and 311 were differentially expressed between the accessions. In accordance with the concept of nonhost resistance in PI272560, genes with similarity to peroxidases, chitinases, ÎČ-1,3-glucanases and other pathogenesis-related genes were up-regulated within the first 8 hai, whereas up-regulation of such genes was delayed in 36554. Moreover, a Phosphoribulokinase gene contributing to nonhost resistance in rice against stripe rust was exclusively expressed in the resistant accession PI272560. Gene expression underpinned physiological and phenotypic observations at the site of infection and are in accordance with the concept of nonhost resistance
Wirkung von Lehrerfortbildungen â Konzeption und Entwicklung eines Tests zur Messung von Lehrerkompetenzen in Stochastik
Die zunehmende Standardisierung von Lehr- und Lernerwartungen setzt
neue Bedingungen fĂŒr die Erhebung von professioneller Kompetenz im Bereich
der Lehreraus- und -fortbildung in der Mathematik. Diese Entwicklung
spiegelt sich in Large-Scale-Assessments wie COACTIV (Kunter et
al., 2011) und TEDS-M (Blömeke, Kaiser & Lehmann, 2010) wider, welche
die Wirkung von Ausbildung und Lehrpraxis auf das Professionswissen
von Mathematiklehrpersonen untersuchen. Die verwendeten Testinstrumente
in diesen Studien sind konzeptionell eher breit angelegt und umfassen
vorrangig zentrale SubdomÀnen der Mathematik in der Sekundarstufe I
(u.a. Algebra, Stochastik, Arithmetik, Geometrie). Dem gegenĂŒber fokussieren
wir in diesem Beitrag die Entwicklung und Pilotierung eines domÀnenspezifischen
Kompetenztests, welcher die Wirkung von Lehrerfortbildungen
fĂŒr den Bereich der Stochastik auf das Professionswissen von
Lehrpersonen in der Primarstufe erfasst. Bisherige Forschungsarbeiten erheben
die Kompetenzentwicklung von Lehrpersonen durch Fortbildungen
in der Regel ĂŒber retrospektive SelbstauskĂŒnfte (Lam & Bengo, 2003). In
diesem Beitrag liegt der Schwerpunkt auf der validen Messung der Wirkung
von Fortbildungen ĂŒber reliable Testinstrumente, die fortbildungsĂŒbergreifend
eingesetzt werden können
Characterization and Assessment of a Novel Plate and Frame MD Module for Single Pass Wastewater ConcentrationâFEED Gap Air Gap Membrane Distillation
Membrane distillation (MD) is an up and coming technology for concentration and separation on the verge of reaching commercialization. One of the remaining boundaries is the lack of available full-scale MD modules and systems suitable to meet the requirements of potential industrial applications. In this work a new type of feed gap air gap MD (FGAGMD) plate and frame module is introduced, designed and characterized with tap water and NaClâH2O solution. The main feature of the new channel configuration is the separation of the heating and cooling channel from the feed channel, enabling a very high recovery ratio in a single pass. Key performance indicators (KPIs) such as flux, gained output ratio (GOR), recovery ratio and thermal efficiency are used to analyze the performance of the novel module concept within this work. A recovery rate of 93% was reached with tap water and between 32â53% with salt solutions ranging between 117 and 214 g NaCl/kg solution with this particular prototype module. Other than recovery ratio, the KPIs of the FGAGMD are similar to those of an air gap membrane distillation (AGMD) channel configuration. From the experimental results, furthermore, a new MD KPI was defined as the ratio of heating and cooling flow to feed flow. This RF ratio can be used for optimization of the module design and efficiency.BMBF, 02WAV1406E, WavE - Verbundprojekt HighCon: Konzentrate aus der Abwasserwiederverwendung, Teilprojekt
Nanoparticulate CpG Immunotherapy in RAO- Affected Horses: Phase I and IIa Study
Background: Recurrent airway obstruction (RAO), an asthma-like disease, is 1 of the most common allergic diseases in horses in the northern hemisphere. Hypersensitivity reactions to environmental antigens cause an allergic inflammatory response in the equine airways. Cytosine-phosphate-guanosine-oligodeoxynucleotides (CpG-ODN) are known to direct the immune system toward a Th1-pathway, and away from the pro-allergic Th2-line (Th2/Th1-shift). Gelatin nanoparticles (GNPs) are biocompatible and biodegradable immunological inert drug delivery systems that protect CpG-ODN against nuclease degeneration. Preliminary studies on the inhalation of GNP-bound CpG-ODN in RAO-affected horses have shown promising results.
Objectives: The aim of this study was to evaluate the clinical and immunological effects of GNP-bound CpG-ODN in a double-blinded, placebo-controlled, prospective, randomized clinical trial and to verify a sustained effect post-treatment.
Animals and Methods: Twenty-four RAO-affected horses received 1 inhalation every 2 days for 5 consecutive administrations. Horses were examined for clinical, endoscopic, cytological, and blood biochemical variables before the inhalation regimen (I), immediately afterwards (II), and 4 weeks post-treatment (III).
Results: At time points I and II, administration of treatment rather than placebo corresponded to a statistically significant decrease in respiratory effort, nasal discharge, tracheal secretion, and viscosity, AaDO2 and neutrophil percentage, and an increase in arterial oxygen pressure.
Conclusion and Clinical Importance: Administration of a GNP-bound CpG-ODN formulation caused a potent and persistent effect on allergic and inflammatory-induced clinical variables in RAO-affected horses. This treatment, therefore, provides an innovative, promising, and well-tolerated strategy beyond conventional symptomatic long-term therapy and could serve as a model for asthma treatment in humans
Immunomodulatory asthma therapy in the equine animal model: A doseâresponse study and evaluation of a longâterm effect
Introduction
Equine asthma represents a naturally occurring animal model for human allergic neutrophilic asthma. Inhalative nanoparticleâbound cytosineâphosphateâguanosine (CpGâGNP) immunotherapy, independent of specific allergens, has already shown promising clinical and immunological results in previous studies and offers the possibility to treat the underlying cause of the disease. This study analyses the relationship between dose and response, and evaluates a possible longâterm effect.
Methods
In the prospective, randomised, doubleâblind clinical field study, 29 horses suffering from equine asthma received 10 inhalation treatments with either 187.5â”g CpGâGNP (CpG single dose [CpGsd]; nâ=â11), 375â”g CpGâGNP double dose (CpG double dose [CpGdd]; nâ=â9) (q48h for 20 days) or 1600â”g beclomethasone (nâ=â9) (q24h for 10 days). Each horse was examined three times: before the treatment (I), immediately after the 10 inhalations (II), and 8 weeks after the final inhalation (III). The three groups were compared according to clinical and laboratory parameters. The study examined the sustainability of the longâterm effect of the treatment after 8 weeks, as well as the tolerability of the formula as a double dose.
Results
The CpGsd resulted in a significant improvement in 82% of the parameters, the CpGdd in 72%. In the longâterm evaluation, the CpGsd showed a significant improvement in 100% of the parameters in comparison to the initial values, the CpGdd in 67%. On the immunological level, the bronchoalveolar lavage revealed a significant reduction of ILâ4, ILâ8, and interferonâÎł.
Conclusion
Both CpG groups displayed significant improvements in clinical and laboratory parameters, especially regarding the longâterm effect of CpGsd. Doubling the CpG dose did not result in any improvement in comparison to the original single dose. On the immunological level, an antiâinflammatory, as well as an immunomodulatory effect, apart from a Th2âdominated immune response, could be observed. This immunomodulatory inhalation treatment could indicate a new possibility for human allergic asthma therapy
Mechanisms contributing to visceral hypersensitivity : focus on splanchnic afferent nerve signalling
This is the peer reviewed version of the following article: Deiteren, A., De Man, J. G., Keating, C., Jiang, W., De Schepper, H. U., Pelckmans, P. A., Francque, S. M. and De Winter, B. Y. (2015), Mechanisms contributing to visceral hypersensitivity: focus on splanchnic afferent nerve signaling. Neurogastroenterology & Motility, 27: 1709â1720, which has been published in final form at doi:10.1111/nmo.12667. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.Visceral hypersensitivity is a main characteristic of functional bowel disorders and is mediated by both peripheral and central factors. We investigated whether enhanced splanchnic afferent signaling in vitro is associated with visceral hypersensitivity in vivo in an acute and postinflammatory rat model of colitis.Peer reviewedFinal Accepted Versio
A comparison of nanoparticullate CpG immunotherapy with and without allergens in spontaneously equine asthma-affected horses, an animal model
Introduction: New therapeutic strategies to modulate the immune response of
human and equine allergic asthma are still under extensive investigation.
Immunomodulating agents stimulating T-regulatory cells offer new treatment
options beyond conventional symptomatic treatment or specific immunotherapy
for human and equine allergic airway diseases, with the goal of a homoeostatic
T-helper cell balance. The aim of this study was to evaluate the effects of a
nebulized gelatin nanoparticle-CpG formulation (CpG-GNP) with and without
specific allergens for the treatment of spontaneous allergic equine asthma as
a model for human asthma. Methods: Twenty equine asthma-affected horses were
treated either with CpG-GNP alone or CpG-GNP with allergens. Two specific
allergens were selected for each horse based on history and an in-vitro test.
Each horse received seven administrations of the respective nebulized
composition and was examined before treatment, immediately after and 6 weeks
after the treatment course. Results: Clinical parameters such as breathing
rate, indirect interpleural measurement, arterial blood gases, amount of
tracheal mucus and percentage of neutrophils and cytokines in tracheal washes
and serum samples were evaluated. Treatment with CpG-GNP alone as well as in
combinations with relevant allergens resulted in clinical improvement of nasal
discharge, breathing rate, amount of secretion and viscosity, neutrophil
percentage and partial oxygen pressure directly after and 6 weeks after
treatment. There were no significant differences between the two treatments in
clinical parameters or local cytokine profiles in the tracheal wash fluid
(IL-10, IFN-g, and IL-17). IL-4 concentrations decreased significantly in both
groups. Conclusion: Nonspecific CpG-GNP-based immunotherapy shows potential as
a treatment for equine and possibly also human allergic asthma
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