Is Nitric Oxide Decrease Observed with Naphthoquinones in LPS Stimulated RAW 264.7 Macrophages a Beneficial Property?

The search of new anti-inflammatory drugs has been a current preoccupation, due to the need of effective drugs, with less adverse reactions than those used nowadays. Several naphthoquinones (plumbagin, naphthazarin, juglone, menadione, diosquinone and 1,4-naphthoquinone), plus p-hydroquinone and p-benzoquinone were evaluated for their ability to cause a reduction of nitric oxide (NO) production, when RAW 264.7 macrophages were stimulated with lipopolysaccharide (LPS). Dexamethasone was used as positive control. Among the tested compounds, diosquinone was the only one that caused a NO reduction with statistical importance and without cytotoxicity: an IC25 of 1.09±0.24 µM was found, with 38.25±6.50% (p<0.001) NO reduction at 1.5 µM. In order to elucidate if this NO decrease resulted from the interference of diosquinone with cellular defence mechanisms against LPS or to its conversion into peroxynitrite, by reaction with superoxide radical formed by naphthoquinones redox cycling, 3-nitrotyrosine and superoxide determination was also performed. None of these parameters showed significant changes relative to control. Furthermore, diosquinone caused a decrease in the pro-inflammatory cytokines: tumour necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6). Therefore, according to the results obtained, diosquinone, studied for its anti-inflammatory potential for the first time herein, has beneficial effects in inflammation control. This study enlightens the mechanisms of action of naphthoquinones in inflammatory models, by checking for the first time the contribution of oxidative stress generated by naphthoquinones to NO reduction

Influence of metal surface preparation on the flexural strength and impact damage behaviour of thermoplastic FRP reinforced metal laminate made by press forming

In this paper the relationship between surface energy and flexural strength of metal laminate made by reinforcing glass fibre reinforced polymer on steel surfaces was investigated. Sand blasting was performed on 22MnB5 steel surface. This steel was stacked together with layers of unidirectional glass/polyamide-6 prepreg, followed by pressing in a hot press. Influenced parameters are pressure, temperature and time. 3D profilometer analysis was used to investigate the roughness profile on the surface of the steel generated by the sand blasting. The surface energy of the steel surface was calculated from a set of contact angles measured by three different liquids. To identify the optimal surface treatment, the variation of surface energy, flexural strength and roughness of the steel surface w as determined as function of the surface treatment. Surface roughness (Ra of 1.08 μm), results indicate that increasing surface roughness leads to improvement in flexural modulus. The increase further leads to decrease in flexural modulus. In addition, the influence of surface energy and flexural strength on the impact damage behaviour was investigated too. The results showed that the sample with highest flexural modulus had the lowest impact-induced damage area

Ergebnisse einer prospektiven Studie

Der Erfolg der einseitigen Cochlea-Implantation (CI) und die zahlreichen Erfolge in der beidseitigen Anpassung von konventionellen Hörgeräten hat dazu geführt, dass auch die bilaterale CI Versorgung für Kinder in den Mittelpunkt des Interesse rückt. Erste Resultate in der bilateralen Versorgung bei Erwachsenen zeigen ein besseres Richtungshören und ein besseres Sprachverstehen im Störschall. In der hier dargestellten Studie wird nachzuweisen sein, inwiefern Kinder hinsichtlich ihres Sprachverstehens - besonders im Störschall - und des Richtungshörens von einer bilateralen Versorgung (NUCLEUS CI 24 M) profitieren. Die Studie wurde mit 2 Gruppen je 10 bilateral simultan implantierter Kinder (Gr. 1 vor dem 2. Lebensjahr, Gr. 2 zwischen dem 2. und 4. Lebensjahr) und der jeweiligen unilateral implantierten Kontrollgruppe konzipiert. Das postoperative Sprachverstehen wird 3 Monate, 6 Monate und jährlich mit der sog. FDA Testbatterie, den Fragebögen nach MAIS und MUSS und einer Rgiometrie überprüft. Die Gesamtentwicklung detektiert eine regelmäßige neuropädiatrische Untersuchung. Bis April 2003 wurden 10 Kinder der Gruppe 1 und 5 Kinder der Gruppe 2 versorgt. Unabhängig vom Lebensalter akzeptierten alle Kinder beide Sprachprozessoren. 70% der Kinder der Gr. 1 zeigten gute Geräuschreaktionen. Hinsichtlich der lautsprachlichen Kommunikation machen die Kinder der Gruppe 2 bessere Fortschritte. Erste Ergebnisse zeigen gute Lokalisationsfähigkeiten aller Kinder. Die ersten Ergebnisse dieser Studie zeigen, dass bilateral implantierte Kinder auch im jüngeren Alter eine hohe Akzeptanz beider Sprachprozessoren haben und gute Lokalisationsfähigkeiten zeigen. Es bleibt nachzuweisen, ob die Sprachentwicklung insgesamt und das Sprachverstehen im Störschall vergleichbare Erfolge zeigt wie bei den erwachsenen Patienten

Opto-elektronisches Empfangsmodul mit substratintegrierter Lichtfuehrung Schlussbericht

Within the acitivities low cost assembly techniques for opto-electronic receiver modules were developed on the basis of the Si-microsystem-technology for the long wavelength region. On the backside of the substrate V-grooves are etched unisotropically for the alignment-free assembly of single mode fibres together with deflecting elements like etched prisms or anodically bonded mirrors. The light is deflected rectangularly to the frontside of the substrate, where a PIN-diode is mounted planarly without submount. The diode design is optimized for low-cost assembly techniques. The substrate simultaniously represents a carrier for an electronic HF-circuitry fabricated in a multilayer thinfilm technology (multi chip technology) and also a package platform with a hermetically tight optical feedthrough. The performance in a frequency range up to 5 GHz with responsivity higher than 0,75 A/W was demonstrated. (orig.)SIGLEAvailable from TIB Hannover: D.Dt.F.QN1(13,38) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman