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The nasal decongestant oxymetazoline (OMZ) exhibits anti-oxidative and antiinflammatory properties (I. Beck-Speier et al., J Pharmacol Exp Ther. 2006;316:842–851). In a follow up study, we hypothesized that OMZ generates pro-resolving lipoxins being paralleled by production of immune-modulating prostaglandin E2 (PGE2) and anti-inflammatory 15(S)-hydroxy-eicosatetraenoic acid [15(S)-HETE] and depletion of pro-inflammatory leukotriene B4 (LTB4). Human neutrophils (PMN) were chosen as the cellular system. The effect of OMZ on these parameters as well as on respiratory burst activity and oxidative stress marker 8-isprostane was analyzed in unstimulated and co-stimulated PMN by ultrafine carbon particles (UCP) or opsonized zymosan (OZ), respectively. In unstimulated cells, OMZ induced formation of PGE2, 15(S)-HETE, and LXA4. The levels of LTB4 and 8-isoprostane were not affected, whereas respiratory burst activity was drastically inhibited. In UCP- and OZ-stimulated control cells, all parameters were elevated. Here, OMZ maintained the increased levels of PGE2, 15(S)-HETE, and LXA4, but substantially suppressed levels of LTB4 and 8-isoprostane and inhibited the respiratory burst activity. These findings suggest a switch from the pro-inflammatory eicosanoid class LTB4 to the pro-resolving LXA4. Since LXA4 is most relevant in returning inflamed tissue to homeostasis, OMZ is postulated to terminate rhinitis-related inflammation, thus contributing to shortening of disease duration. Keywords:: oxymetazoline, rhinitis, neutrophil, eicosanoid, lipoxin A4

InGaN/GaN nanowire arrays (NWAs) exhibit efficient photoluminescence (PL) which persists to temperatures of 200 °C and beyond. The PL characteristics exhibit chemical sensitivity when the NWAs are exposed to gases or liquids. Gas sensing tests on such arrays reveal both quenching and enhancing PL responses, depending on the kinds of gases chosen and NWA operation conditions employed. A characteristic observed for all kinds of analytes is that the concentration dependence of the PL response consistently follows Langmuir isotherms which are easy to interpret regarding adsorbate-specific adsorption energies. Another characteristic feature is that best-fitting adsorption energies do not reveal as species-dependent constants but rather follow linear dependencies on temperature with species-dependent slopes. We show that this behavior can be explained by a competition of test gases and background gases for common adsorption sites. A particularly interesting gas species is water vapor, which can form competing adsorbates with quenching and enhancing characteristics. Unlike oxidizing gas species (O2, NO2, and O3) and water vapor, reducing gas species do not exhibit an intrinsic ability to modify the PL yield. Reducing gas species, rather, are detected in an indirect manner by consuming quenching oxygen adsorbates and by forming enhancing H2O ones as these interact with oxygen species coadsorbed in reactive backgrounds of ambient or synthetic air.

The photoluminescence properties of InGaN/GaN nanowire arrays were used to probe the adsorption of H 2 O, O 2 , NO 2 and O 3 on III-nitride surfaces. Upon adsorption these gases either enhance (H 2 O) or quench (O 2 , NO 2 , O 3 ) the photoluminescence intensity which allows the related adsorption processes to be evaluated. An analysis of the experimental data in terms of the Langmuir Adsorption and Recombination model reveals that – at room temperature – the Langmuir energy of adsorption E ads increases in the order H 2 O, O 2 , NO 2 , and O 3 and that for each gas species E ads increases linearly with increasing surface temperature. We show that this behaviour can be explained by a competition of these air constituents for the same kind of Ga(In) adsorption sites. In contrast, exploratory experiments with H 2 and simple hydrocarbons reveal that these reducing species neither quench nor enhance the native photoluminescence response, which indicates that these do not compete for the same adsorption sites as the background air constituents.

NO 2 sensing tests have been performed on room-temperature-operated SnO 2 gas sensors. Due to elongated response and recovery time constants these sensors exhibited a dosimeter rather than a conventional concentration-dependent NO 2 response. In order to enable continuous monitoring such sensors need to be subjected to periodically repeated sense & reset operations. Reset procedures which proved to be effective in restoring baseline conductance again are low-temperature annealing (T ∼ 120 °C), ultraviolet (UV) light exposure, and exposure to humidified synthetic air (T ∼ 300 K, r.h. ∼ 80%). Unlike high-temperature gas sensors, room-temperature operated sensors exhibit very little intrinsic sensor drift. Severe levels of sensor drift, however, can arise from contamination-induced effects in the sensor periphery. It is demonstrated that such contamination-induced sensor drifts can be effectively compensated by exploiting the knowledge about the timing of the sense & reset operations.

We demonstrate that the complex adsorption behavior of H2O on InGaN/GaN nanowire arrays is directly revealed by their ambient-dependent photoluminescence properties. Under low-humidity, ambient-temperature, and low-excitation-light conditions, H2O adsorbates cause a quenching of the photoluminescence. In contrast, for high humidity levels, elevated temperature, and high excitation intensity, H2O adsorbates act as efficient photoluminescence enhancers. We show that this behavior, which can only be detected due to the low operation temperature of the InGaN/GaN nanowires, can be explained on the basis of single H2O adsorbates forming surface recombination centers and multiple H2O adsorbates forming surface passivation layers. Reversible creation of such passivation layers is induced by the photoelectrochemical splitting of adsorbed water molecules and by the interaction of reactive H3O+ and OH– ions with photoactivated InGaN surfaces. Due to electronic coupling of adsorbing molecules with photoactivated surf...

III-nitride semiconductors (AlGaN, GaN and InGaN) have received considerable attention in various fields ranging from high-frequency and high-temperature electronics [1] to LED lighting technologies [2]. [...]

We report on an innovative use of high-temperature MEMS heater platforms as micro pellistor spectrometers. MEMS heater elements, initially designed for use as thermal infrared emitters, were fitted with thin-film noble metal layers to enable catalytic combustion processes on the hotplate surface. The modified heater platforms were operated in a range of combustible gas ambients while applying saw-tooth-like heater waveforms. Measurements of this kind revealed the heat of reaction vs. hotplate temperature profiles for each individual gas. We find that different families of gases yield distinctly different heat of reaction vs. temperature profiles and that these profiles allow the different families, and members inside some of these families, to be distinguished.

A non-dispersive infrared (NDIR) sensor system has been designed to monitor the state of contamination and degradation of aviation hydraulic fluids. Core part of this system is a MOEMS subsystem consisting of a micro cuvette, a MEMS thermal IR emitter and a four-channel thermopile array. For ruggedness, this MOEMS subsystem is integrated into a high-pressure resistant metal package. The MOEMS subsystem measures the transparency of the fluid under test at four specifically chosen spectral channels. Three of these channels allow the water content, the total acidity number and the remaining acid scavenger reserve to be monitored. The forth channel serves for calibration and self-test purposes. Fluid monitoring systems of this kind will form key components in an innovative AIRBUS aircraft maintenance system.

We demonstrate that the complex adsorption behavior of H

We report on an all-optical sensor system that employs GaN/InGaN nanowire heterostructures (NWH) as optochemical transducers. When exposed to ultraviolet light, such NWHs emit green luminesce light. This photoluminescence (PL) is intense and temperature stable, and persists up to transducer temperatures well beyond 200 °C. When exposed to oxidizing gases such as O 3 , NO 2 , and O 2 the PL intensity decreases. At room temperature minimum detectable O 3 -, NO 2 -, and O 2 -concentrations are 50 ppb, 500 ppb and 100 ppm, respectively. Above their minimum detectable concentrations the O 3 , NO 2 and O 2 responses increase in a quasi-logarithmic manner up to a temperature-dependent saturation level. It is shown that the observed features can be explained within a model of Langmuir adsorption and surface recombination.

Microelectromechanical systems (MEMS) with integrated heaters, originally designed for the readout of the resistance of metal oxide (MOX) layers, were configured to observe surface ionisation (SI) gas signals. Interdigital platinum (Pt) electrodes on top of the dielectric membranes acted as ion emitting layers while flat-plate counter electrodes, positioned at a short distance above them, were used for the current readout. In this work, we show that this device configuration leads to SI responses orders of magnitude higher than those previously reported for thin-film, flat-plate devices and fully comparable to the performance of parallel-nanowire devices (PNDs). The high ionisation efficiency of our MEMS devices, which are suitable for large-scale production and further integration steps, is attributed to the electric field enhancement that takes place at the sharp edges of the Pt electrodes.

Angesichts widerspruchlicher Entwicklungen der sozialen Berufe (vgl.zuchner/schilling 2010) und zugleich der sehr unterschiedlichen Deutungen der sozialpolitischen Veranderungen in Deutschland gewinnt die Frage der Entwicklung der Berufsgruppe der SozialarbeiterInnen/SozialpadagogInnen1eine zunehmende Bedeutung: Immerhin hat diese Berufsgruppe inzwischen eine Grosenordnung erlangt, die der Gesamtheit der niedergelassenen Arzte in Deutschland entspricht2. Zugleich ist die Zahl der in ihrem Beruf tatigen SozialarbeiterInnen/SozialpadagogInnen ein guter Indikator dafur, welche Bedeutung die Gesellschaft diesem “offentlich-beruflich organisierten Grundversorgungssystem jenseits sozialpolitisch-materieller Sicherungssysteme„ (Rauschenbach 1999, S. 28) beimisst.

Little is known about health effects of ultrafine particles (UFP) found in ambient air, but much of their action may be on cells of the lung, including cells of the monocyte/macrophage lineage. We have analyzed the effects of diesel exhaust particles (DEP; SRM1650a) on human monocytes in vitro. DEP, on their own, had little effect on cyclooxygenase (COX)-2 gene expression in the Mono Mac 6 cell line. However, when cells were preincubated with DEP for 1 h, then stimulation with the Toll-like receptor 4 (TLR4) ligand lipopolysaccharide (LPS) induced an up-to fourfold-higher production of COX-2 mRNA with an average twofold increase. This costimulatory effect of DEP led to enhanced production of COX-2 protein and to increased release of prostaglandin E2 (PGE2). The effect was specific in that tumor necrosis factor gene expression was not enhanced by DEP costimulation. Furthermore, costimulation with the TLR2 ligand Pam3Cys also led to enhanced COX-2 mRNA. DEP and LPS showed similar effects on COX-2 mRNA in primary blood mononuclear cells, in highly purified CD14-positive monocytes, and in monocyte-derived macrophages. Our data suggest that UFP such as DEP may exert anti-inflammatory effects mediated by enhanced PGE2 production.

Recent studies have shown that long-term in vivo exposure of dogs to neutral sulfur(IV)/sulfite aerosols induces mild inflammatory reactions, whereas the combination of neutral sulfite with acidic sulfur(VI)/sulfate aerosols evokes less pronounced effects. To understand underlying mechanisms, we studied in vitro the role of lipid mediators in the responses of alveolar macrophages (AMs) to sulfur-related compounds under neutral (pH 7) or moderate acidic (pH 6) conditions. Canine AMs incubated with sulfite at pH 7 released threefold higher amounts of platelet-activating factor than control (P

Background Programmed cell death, also termed apoptosis, is the main focus of interest in a variety of scientific and clinical areas. For a better understanding of the mechanisms of apoptosis, from the onset of the cellular death program to the late stages of apoptosis or apoptotic necrosis, very early functional events have to be quantified because they might be involved in temporal and causal relationships between apoptosis-related key processes. Methods We have established a flow cytometric technique to quantify time-dependent signals simultaneously with high temporal resolution (Δt = 1 s) in living cells. With this technique, the response of cells to apoptosis-stimulating agents can be analyzed over 15 min. For this purpose, a thermostatted sample tube holder for repeatable interruption-free injection of substances into the cell suspension was developed. Early detectable fluorescence and scatter parameters were related to intracellular free Ca2+ concentration, [Ca2+]i (Indo-1 fluorometry), membrane permeability (propidium iodide [PI] influx), and cell volume (forward scatter). Results A T-cell line (Jurkat) served as a model system. Apoptosis was induced by the biozid Tri-n-butyltin (TBT). Dependent on the TBT concentration (0.3–10 μM), the mean free [Ca2+]i increased by a factor of 1.2–6 during a short time interval of just 2 min. Especially after low TBT concentrations (

Bronchiolitis obliterans syndrome (BOS) is the most serious long-term sequel of lung or heart-lung transplantation (H/LTX). Neutrophilia in the lower respiratory tract is a prominent feature of BOS. Because polymorphonuclear leukocytes (PMN) are capable of releasing large quantities of reactive oxygen species, we measured indicators of oxidative stress and glutathione levels representing antioxidant defense in H/LTX patients (HLTX, n=6; double-LTX, n=7; single-LTX, n=9). We analyzed 19 bronchoalveolar lavage (BAL) samples from 13 non-BOS patients (nine female, four male: age 39+/-4 years) and 17 BAL samples from nine BOS patients (five female, four male: age 33+/-2 years). PMN were the predominant BAL cell population in BOS (61.7+/-7.8% vs. 12.3+/-3.4%, P

Alveolar macrophages (AM) were studied for their capability to release mediators involved in modulation of neutrophil (PMN) functions. Initial responses were induced by sulphite. Supernatants obtained from canine, human and rat AM pre-treated with sulphite in concentrations of 0.1–2 mmol/L enhanced the respiratory burst of canine, human and rat PMN, measured by lucigenin-dependent chemiluminescence (CL). This PMN-stimulating activity exhibited platelet-activating factor (PAF)-like properties, as indicated by desensitization of the PAF receptor, inhibition with PAF antagonists WEB 2086 and CV 3988, and the kinetic CL response like PAF after chloroform extraction of supernatants inhibitable by PAF antagonist CV 3988. These results indicate that AM are triggered by sulphite to release mediators that activate the respiratory burst of PMN, primarily via the PAF receptor. © 1998 John Wiley & Sons, Ltd.

In fibrosing alveolitis (FA), activated phagocytes cause excessive oxidative stress in the lower respiratory tract. Additionally, levels of glutathione, a major antioxidant of the human lung, are markedly reduced. Since N-acetylcysteine (NAC) is a known precursor for glutathione synthesis, we investigated the effect of NAC on redox balance and lung function in FA. Eighteen patients with an established diagnosis of FA were treated with 600 mg NAC three times daily for 12 wk in addition to their latest immunosuppressive therapy. Before and after NAC therapy, pulmonary function tests (PFTs) and bronchoalveolar lavage (BAL) were performed. BAL fluid was analyzed with regard to cell differential, glutathione status, and methionine sulfoxide content of BAL proteins (Met(O)), as an indicator of oxidative stress at the alveolar surface. There was an increase of total glutathione (GSHt = GSH +/- 2 x GSSG: 3.43 +/- 0.30 microM versus 4.20 +/- 0.66 microM, p < 0.05) and of reduced glutathione (GSH: 2.58 +/- 0.24 microM versus 3.42 +/- 0.54 microM, p < 0.005) in native BAL fluid and in the epithelial lining fluid (GSHt: 267.3 +/- 26.0 microM versus 367.1 +/- 36.0 microM, p < 0.005; GSH: 204.5 +/- 20.7 microM versus 302.9 +/- 32.2 microM, p < 0.005). The increase of GSH was accompanied by a decrease of Met(O) (6.83 +/- 0.71% versus 4.60 +/- 0.40%, p < 0.005). PFTs significantly improved during NAC treatment. We conclude that high-dose NAC significantly improved the antioxidant screen of the lungs by elevating GSH levels. Moreover, the decrease of Met(O) levels indicated an antioxidant effect at the alveolar surface. These biochemical changes were accompanied by an improvement of PFTs in patients under maintenance immunosuppression. NAC supplementation should, therefore, be considered as an adjunct therapy for FA.

This paper reports the design, fabrication and proof of concept of microelectromechanical systems (MEMS) with integrated heaters configured to observe surface ionization (SI) gas signals. Active interdigital electrodes (IDEs) on the top of the membrane are the emitting element, and a flat-plate counter electrode positioned at a short distance above the MEMs is the ion collector. These devices, which are suitable for large-scale production and further integration steps, exhibit high ionization efficiency fully comparable to that observed with individual nanowires.

The paper presents a novel concept for the realization of optochemical sensor systems which are capable of operating in harsh environments. Key components in such sensors are nanostructures formed from gallium nitride (GaN) and its alloys with aluminum (Al) and indium (In). Nanostructures of this kind emit an efficient, visible-light photoluminescence (PL) which can be excited with low-cost ultraviolet light sources and which extends up to temperatures in the order of 200°C. When exposed to various chemical environments, changes in the PL intensity occur which constitute valuable sensor signals. Due to the all-optical approach, the PL can be excited and its chemically induced changes be read out without requiring electrical wiring at the point of measurement. The present paper presents this innovative sensor concept, the nanostructures and optochemical transducer structures that form its material base, as well as several applications of such transducers in the fields of gas and fluid sensing. The applications addressed here range from the sensing of ppb concentrations of H 2 , NO 2 and O 3 in gaseous environments to the pH monitoring in aqueous solutions.

Im folgenden Kapitel steht eine Bevolkerungsgruppe im Mittelpunkt, die zahlenmasig immer recht gering war, jedoch auf Dauer in der baltischen Region ein Mas an Autonomie und Selbstandigkeit, an Dominanz und Machtposition erfuhr, wie die Geschichte nur wenige Beispiele kennt. Nicht die gegenwartige Bedeutung der Deutschen im Baltikum findet hier das Interesse, sondern die Wechselfalle, Kontinuitaten und Bruche der Vergangenheit fur diese Bevolkerung, die bis ins 18. Jahrhundert hinein keine nationale Eigenbezeichnung kannte, schlieslich die regionale Kategorie „Balten“ wahlte und sich erst im Zeitalter nationaler Identitatssuche und -findung im Laufe des 19. Jahrhunderts als „Deutschbalten“ bezeichnete.1 Der Terminus „Baltendeutsche“ blieb vorrangig der NS-Ideologie und deren Vertretern vorbehalten. Mit der Umsiedlung der Deutschbalten 1939/41 (vgl. dazu Loeber 1972) fand die Geschichte dieser Gruppe in der baltischen Region ein Ende, wobei diese Siedlungsregion aufgrund der historischen Entwicklung in erster Linie die heutigen unabhangigen Staaten Estland und Lettland umfasst, die Bedeutung der Deutschbalten jedoch bisweilen weit uber die Grenzen dieses Gebietes ausstrahlte.2

Am 20. August 1991 erklarte der Oberste Sowjet der Estnischen Sozialistischen Sowjetrepublik (ESSR) die Ubergangszeit zur Erlangung der Unabhangigkeit Estlands fur beendet. Diesem vorlaufigen Endpunkt in der staatlichen Entwicklung der nordlichsten Republik des Baltikums gingen — seit der Verkundung der Prinzipien von Glasnost’ und Perestrojka durch Michail Gorbatschow 1985 — spannungsreiche Jahre voraus, in denen die Bemuhungen der estnischen Bevolkerung um die Wiederherstellung der nationalen Souveranitat auch kritische Phasen durchliefen.

Im Zuge der quantitativen und qualitativen Ausdehnung der Sozialen Arbeit wurde die Ausbildung von SozialarbeiterInnen/SozialpadagogInnen 1970 auf das Hochschulniveau angehoben, seither entwickelte sich Soziale Arbeit zu einer veritablen Wissenschaft: In den Studiengangen Soziale Arbeit waren im Jahr 2006 938 Professuren registriert, davon 83 an Universitaten, die ubrigen an Fachhochschulen (Statistisches Bundesamt 2007; vgl. Amthor 2008, S. 63f). Wenn man die Hochschulen in Osterreich und der deutschsprachigen Schweiz hinzurechnet, so erhoht sich die Zahl der Scientific Community Soziale Arbeit im deutschen Sprachraum auf ca. 1300 Professuren und eine zunehmende Zahl von wissenschaftlichen MitarbeiterInnen. Der Vorwurf, dass „eine nicht zu vernachlassigende Zahl der ProfessorInnen (…) den Fachbereich Sozialwesen als Nische fur sich entdeckt und dort eine Professur angestrebt (hat), weil sie den Titel und das Gehalt, die Pension und die Zeit fur Nebentatigkeiten haben wollten“ und keinerlei Bereitschaft zeigen, sich auf den Diskurs um Soziale Arbeit einzulassen (Engelke 2003, S. 463; Engelke/Borrmann/Spatschek 2008, S. 382) ist sicherlich nicht mehr haltbar (wenn er in dieser Verallgemeinerung je legitim war). Die „BezugswissenschaftlerInnen“ haben erheblich beigetragen zur Entwicklung spezieller Handlungstheorien und insbesondere betrachtliche Forschungsleistungen in die Soziale Arbeit eingebracht (vgl. Maier 2009; Maier 2007) – Zugleich hat sich nach meiner Wahrnehmung das Selbstverstandnis der „lehrenden SozialarbeiterInnen“ an den Fachhochschulen grundlegend verandert: sie definieren sich zunehmend als SozialarbeitswissenschaftlerInnen, die ihre besondere Aufgabe nicht mehr in der Praxisorientierung sondern in der Entwicklung einer Wissenschaft Soziale Arbeit sehen.

The nasal decongestant oxymetazoline effectively reduces rhinitis symptoms. We hypothesized that oxymetazoline affects arachidonic acid-derived metabolites concerning inflammatory and oxidative stress-dependent reactions. The ability of oxymetazoline to model pro- and anti-inflammatory and oxidative stress responses was evaluated in cell-free systems, including 5-lipoxygenase (5-LO) as proinflammatory, 15-lipoxygenase (15-LO) as anti-inflammatory enzymes, and oxidation of methionine by agglomerates of ultrafine carbon particles (UCPs), indicating oxidative stress. In a cellular approach using canine alveolar macrophages (AMs), the impact of oxymetazoline on phospholipase A(2) (PLA(2)) activity, respiratory burst and synthesis of prostaglandin E(2) (PGE(2)), 15(S)-hydroxy-eicosatetraenoic acid (15-HETE), leukotriene B(4) (LTB(4)), and 8-isoprostane was measured in the absence and presence of UCP or opsonized zymosan as particulate stimulants. In cell-free systems, oxymetazoline (0.4-1 mM) inhibited 5-LO but not 15-LO activity and did not alter UCP-induced oxidation of methionine. In AMs, oxymetazoline induced PLA(2) activity and 15-HETE at 1 mM, enhanced PGE(2) at 0.1 mM, strongly inhibited LTB(4) and respiratory burst at 0.4/0.1 mM (p < 0.05), but did not affect 8-isoprostane formation. In contrast, oxymetazoline did not alter UCP-induced PLA(2) activity and PGE(2) and 15-HETE formation in AMs but inhibited UCP-induced LTB(4) formation and respiratory burst at 0.1 mM and 8-isoprostane formation at 0.001 mM (p < 0.05). In opsonized zymosan-stimulated AMs, oxymetazoline inhibited LTB(4) formation and respiratory burst at 0.1 mM (p < 0.05). In conclusion, in canine AMs, oxymetazoline suppressed proinflammatory reactions including 5-LO activity, LTB(4) formation, and respiratory burst and prevented particle-induced oxidative stress, whereas PLA(2) activity and synthesis of immune-modulating PGE(2) and 15-HETE were not affected.

Das im Jahre 1999 gestartete Bund-Lander-Programm „Soziale Stadt“ ist vermutlich das anspruchvollste und komplexeste gesellschaftspolitische Programm, das in der Bundesrepublik je eingefuhrt wurde. Das Deutsche Institut fur Urbanistik (Difu) hat die Zielsetzung dieses Programms ruckblickend folgendermasen zusammengefasst: „Insgesamt geht es um eine Verbesserung der physischen Wohn- und Lebensbedingungen (uberwiegend durch baulich-investive Masnahmen und Projekte), der individuellen Lebenschancen (durch Vermittlung von Fahigkeiten, Fertigkeiten und Wissen, Eroffnung von Zugangsmoglichkeiten in den Arbeits- und Wohnungsmarkt sowie Hilfen zur Selbsthilfe) sowie des Gebietsimage, der Stadtteiloffentlichkeit und Identifikation mit den Quartieren (auf Basis konkreter Stabilisierungs- und Revitalisierungsmasnahmen). Dies soll mit den Strategien der Bundelung humaner und materieller Ressourcen, der Aktivierung aller lokalen und lokal relevanten Akteure sowie der Einrichtung neuer Management- und Organisationsstrukturen erreicht werden“ (Arbeitspapiere zum Programm Soziale Stadt 2003: 6).

Agglomerates of ultrafine particles (AUFPs) may cause adverse health effects because of their large surface area. To evaluate physiologic responses of immune cells, we studied whether agglomerates of 77-nm elemental carbon [(EC); specific surface area 750 m2/g] and 21 nm titanium dioxide (TiO(2) particles (specific surface area 50 m(2)/g) affect the release of lipid mediators by alveolar macrophages (AMs). After 60-min incubation with 1 microg/mL AUFP-EC (corresponding to 7.5 cm(2) particle surface area), canine AMs (1 x 10(6) cells/mL) released arachidonic acid (AA) and the cyclooxygenase (COX) products prostaglandin E(2) (PGE(2), thromboxane B(2), and 12-hydroxyheptadecatrienoic acid but not 5-lipoxygenase (5-LO) products. AUFP-TiO(2) with a 10-fold higher mass (10 microg/mL) than AUFP-EC, but a similar particle surface area (5 cm(2) also induced AMs to release AA and COX products. Agglomerates of 250 nm TiO(2) particles (specific surface area 6.5 m(2)/g) at 100 microg/mL mass concentration (particle surface area 6.5 cm(2) showed the same response. Interestingly, 75 cm(2)/mL surface area of AUFP-EC and 16 cm(2)/mL surface area of AUFP-TiO(2) additionally induced the release of the 5-LO products leukotriene B(4) and 5-hydroxyeicosatetraenoic acid. Respiratory burst activity of stimulated canine neutrophils was partially suppressed by supernatants of AMs treated with various mass concentrations of the three types of particles. Inhibition of neutrophil activity was abolished by supernatants of AMs treated with COX inhibitors prior to AUFP-incubation. This indicates that anti-inflammatory properties of PGE(2) dominate the overall response of lipid mediators released by AUFP-affected AMs. In conclusion, our data indicate that surface area rather than mass concentration determines the effect of AUFPs, and that activation of phospholipase A(subscript)2(/subscript) and COX pathway occurs at a lower particle surface area than that of 5-LO-pathway. We hypothesize a protective role of PGE(2) in downregulating potential inflammatory reactions induced by ultrafine particles.

Background Human polymorphonuclear granulocytes (PMN) are an essential component in the immunological defense network against a variety of harmful pathogens. We have studied the effects of the airborne pollutant sulfite on the calcium metabolism and respiratory burst of these cells simultaneously. Methods A flow cytometric method was developed using the fluochromes Indo-1 and DHR-123. This method allowed us to investigate the real-time kinetics of intracellular free calcium and reactive oxygen intermediates in viable cells with a temporal resolution of 1 s over a time course of 17 min. An additional feature was the possibility to discriminate between reacting and nonreacting cells after treatment with defined stimuli, thus gaining additional insight into the behavior of cell subpopulations. Results We analyzed the effects of sulfite on PMN before and after stimulation with formyl-Met-Leu-Phe (FMLP). Treatment with sulfite alone (0.001–1 mM) caused a small, nontransient increase in intracellular calcium. Preincubation with sulfite reduced the maximal calcium response elicited by FMLP. A significant increase in steady-state calcium levels after stimulation with FMLP was observed after treatment with sulfite in concentrations of 10 and 100 mM. Regarding the respiratory burst, treatment with sulfite alone in concentrations of 0.001–1 mM induced a significant increase in DHR-123–derived fluorescence, whereas concentrations of 5 and 10 mM caused a significant depression of this fluorescence below baseline values. Sulfite caused a maximal twofold increase of DHR-123–derived fluorescence compared with the FMLP response. Similar results were obtained after preincubation with sulfite before treatment with FMLP, showing that the effect of sulfite on the respiratory burst was additive to the FMLP response. Regarding the fractions of responding cells, treatment with sulfite up to 1 mM induced a concentration-dependent increase of burst-reactive PMN, whereas preincubation before stimulation with FMLP showed no correlation between sulfite concentration and fraction of burst-reacting cells. Conclusions By simultaneous registration of [Ca2+]i and [H2O2]i of PMN after treatment with FMLP and sulfite, the essential responses were already observed within a short time interval (15 min). Striking differences were found in the response of calcium as second messenger and respiratory burst in PMN treated with sulfite. Until a critical concentration (0.5–1 mM), sulfite caused a concentration-dependent increase of [H2O2]i, in addition to the FMLP-induced response. The [Ca2+]i changes induced by sulfite alone, however, were found to be small and showed no correlation with the respiratory burst response. Cytometry 40:219–229, 2000 © 2000 Wiley-Liss, Inc.

Glutathione-dependent formaldehyde dehydrogenase (FDH; EC 1.2.1.1) has been purified 3900-fold from maize cell-suspension cultures to a specific activity of 4.68 mumol (mg protein)-1 min-1. The homogeneous enzyme consisted of two identical subunits with a molecular mass of 42 kDa, and an isoelectric point of 5.8. Eight tryptic peptides were sequenced and gave a perfect fit to the protein sequence derived from maize Fdh cDNA (J. Fliegmann and H. Sandermann, 1997, Plant Mol Biol 34: 843-854). There was 62% identity with the eucaryotic FDH consensus sequence. Michaelis constants of approx. 20 microns (formaldehyde), approx. 50 microns (glutathione) and approx. 31 microns (NAD+) were determined for the maize enzyme as well as for FDH partially purified from dog lung. Besides S-hydroxymethylglutathione, pentanol-1, octanol-1, and omega-hydroxy-fatty acids served as substrates for both FDH preparations. The unusual substrate specificity indicates that FDH may be involved in the detoxification of long-chain lipid peroxidation products.

Publisher Summary Specific oxidation of one or more methionine residues in a number of methionine-containing peptides, proteins, and enzymes has been recognized as an important regulatory principle, including control of chemotaxis, metabolic pathways, and sequence-independent recognition of nonpolar protein surfaces. Analysis of protein-bound methionine sulfoxide in tissue samples or body fluids from inflammatory sites and the correlation of this parameter with functional and structural changes appear to be a promising way to assess oxidative tissue injury. To quantify the relative methionine sulfoxide content in proteins, methionine and methionine sulfoxide must be determined simultaneously by amino acid analysis. However, a direct analysis of methionine sulfoxide in acid hydrolysates is subject to considerable error. Methionine is oxidized to methionine sulfoxide when the methionine sulfoxide content is low in comparison to the total methionine in proteins. The indirect method, using alkylation followed by performic acid oxidation, sometimes results in an underestimation of methionine sulfoxide, especially for proteins containing small amounts of the oxidized amino acid. The analysis of protein-bound methionine sulfoxide according to the cyanogens bromide procedure presented in the chapter includes (1) appropriate sample preparation, (2) quantitative conversion of nonoxidized methionine to homoserine and homoserine lactone, (3) acid hydrolysis under reducing conditions, (4) a quantitative conversion of homoserine lactone to homoserine, and (5) a simultaneous analysis of homoserine and residual methionine by reversed-phase high-performance liquid chromatography (HPLC) after precolumn derivatization with o-phthaldialdehyde.

Proteins of human bronchoalveolar lavage fluids, obtained by washing the epithelial lining fluid of the lungs with phosphate-buffered saline, were analyzed by two-dimensional electrophoresis under denaturating and reducing conditions. The two-dimensional pattern of bronchoalveolar lavage fluid proteins of healthy volunteers (controls) were compared with those of patients with idiopathic pulmonary fibrosis, sarcoidosis, and asbestosis. Particular interest was paid to the proteins present in minor amounts mainly in the low molecular weight region of the gels. Marked changes in single protein spots were observed. In idiopathic pulmonary fibrosis the spot intensity of the surfactant-associated protein, SP-A, showing isomeric forms both in charge and in molecular weight, was markedly decreased. In sarcoidosis, the immunoglobulins (IgG, IgA) and a group of protein spots at an isoelectric point of 4.5-5.0 and a molecular mass of 55 kDa were increased. An additional spot appeared at an isoelectric point of 4.5 and a molecular mass of 12 kDa. In particular in asbestosis, but also in some cases of idiopathic pulmonary fibrosis and sarcoidosis, the number and intensity of low molecular weight proteins were increased strongly.

Changes in the oxidative status in the soluble proteins of bronchoalveolar lavage (BAL) fluid from monkeys were examined during 26 months of individual or combined exposure to quartz dust (5 mg/m3 of DQ12) and a hyperbaric atmosphere (2.5 bar). The oxidation of BAL proteins, assumed to be an indicator for oxidative stress in the lungs, was determined by measuring the amount of carbonyl groups in their amino acid side chains. The carbonyl content of BAL proteins (nmol carbonyl/mg protein) increased steadily to a maximum value of 156% of the control after 6 months exposure to hyperbaric atmosphere, and decreased below 50% of control levels in both the quartz alone exposed group and the group exposure to quartz in combination with a hyperbaric atmosphere. The effect of quartz on the production of reactive oxygen species by BAL cells was investigated in vitro. BAL cells from healthy monkeys preincubated with quartz and stimulated with phorbolmyristate acetate (PMA) produced reduced levels of extracellular superoxide anion and intracellular hydrogen peroxide compared with PMA-only stimulated cells. Thus the lowered carbonyl content of BAL proteins in the quartz exposed groups may have resulted from reduced production of the hydrogen peroxide which is essential for carbonyl formation by phagocytes. Changes in carbonyl content of BAL protein in vivo may be a new indicator for potential subsequent lung damage.

Oxidative inactivation of various key enzymes and alpha-1-proteinase inhibitor (alpha-1-PI) was studied by treatment with N-chloramines and the metal-catalyzed oxidation (MCO)-systems ascorbate/Fe(III) and ascorbate/Cu(II). Chlorinated amines completely inhibited alpha-1-PI, fructose-1,6-bis phosphatase (Fru-P2ase) and glyceraldehyde phosphate dehydrogenase (GAPD) at a low molar excess, and glucose-6-phosphate dehydrogenase (G6PD) at a high molar excess, but did not impair beta-N-acetylglucosaminidase (beta-NAG), alkaline phosphatase (AP) or lactate dehydrogenase (LDH). MCO-systems affected the activities of Fru-P2ase, GAPD, AP, LDH and G6PD, but not those of beta-NAG or alpha-1-PI. EDTA prevented inactivation of Fru-P2ase, G6PD and LDH by ascorbate/Cu(II) and of Fru-P2ase by ascorbate/Fe(III) suggesting a site-specific oxidation catalyzed by a protein-bound metal ion. In conclusion, N-chloramines and MCO-systems exhibited different properties with regard to oxidative inactivation, sulfhydryl-enzymes were susceptible to both systems, but other enzymes were only susceptible to one or neither system.

Excessive release of reactive oxygen metabolites (ROM) from lung inflammatory cells has been claimed to be of major pathogenetic significance in diffuse fibrosing alveolitis. In the present study, the content of oxidized methionine residues [Met(O)] as a percentage of total methionine (Met) in BAL-derived proteins was used to assess the biologic effect of ROM. In addition, procollagen-III-peptide was measured in BAL fluid as a marker of fibroblast activation. We investigated bronchoalveolar lavage (BAL) samples from seven control patients without evidence of interstitial lung disease and from 42 patients with fibrosing alveolitis caused by idiopathic pulmonary fibrosis (IPF), n = 20, or by collagen vascular disease (CVD), n = 22. Met(O) was elevated in the patients with IPF or CVD compared with that in the control subjects (8.86 +/- 1.26 and 8.13 +/- 1.44% versus 3.36 +/- 0.49%, p less than 0.01 and p less than 0.05, respectively; mean +/- SEM). A positive correlation was found between percentage of neutrophils in BAL and Met(O) in both groups separately and combined (IPF, r = 0.84; p less than 0.001; CVD, r = 0.44; p less than 0.05; IPF and CVD, r = 0.60; p less than 0.001), whereas an inverse relationship existed between Met(O) and the percentage of alveolar macrophages in BAL (IPF, r = -0.59; p less than 0.01; CVD, r = -0.24; NS; IPF and CVD, r = -0.41; p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Cells obtained from bronchoalveolar lavage, or neutrophils of peripheral blood of dog, were incubated with the canine surfactant-associated protein A (SP-A). A significant decrease of the production of Superoxide anion was observed after subsequent stimulation with phorbol-12-myristate-13-acetate (PMA) as measured by the lucigenin-dependent chemiluminesence (CL). Several other proteins used for control experiments did not decrease lucigenin-dependent CL, indicating a specific effect of SP-A on phagocytes. Treatment of SP-A with collagenase prior to incubation with neutrophils destroyed the depleting effect on oxygen radical production of PMA-stimulated cells. We propose that SP-A acts as a regulatory factor of the respitatory burst of alveolar macrophages and neutrophils in the lungs. The inhibitory effect of SP-A is down-regulated by collagenase released from stimulated alveolar macrophages.

Proteins of dog bronchoalveolar lavage fluid, obtained by washing the epithelial lining layer of lungs with phosphate-buffered saline, were separated by two-dimensional electrophoresis. Due to the low protein and high salt content of the bronchoalveolar lavage fluid, samples had to be concentrated and desalted. Following electrophoresis the protein spots were visualized by silver staining. Comparing the two-dimensional protein patterns of bronchoalveolar lavage fluid with that from serum, several lung-specific proteins were detected. The most prominent protein, most probably a surfactant-associated protein, showed isoforms with isoelectric points in the range of pH 4.2-4.8, and a molecular mass of 32 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis after reduction with dithiothreitol.

Five independently isolated glutathione-deficient (gsh-) mutants of Saccharomyces cerevisae with maximally 6% residual glutathione content have been analysed genetically. Complementation as well as tetrad analysis of the homo- and heterozygous diploids constructed by suitable crosses of the five mutants indicated that all isolates belong to one complementation group and hence represent different alleles of one gene, GSH1. In order to determine the Gsh1 gene product an assay suitable for yeast was developed to determine the activity of gamma-glutamyl-cysteine synthetase catalysing the first step of glutathione biosynthesis. All mutants are severely deficient in gamma-glutamyl-cysteine synthetase (less than 6.5% of the activity of the glutathione competent parental strain) which is in good accordance with the genetic data.

In proteins released from quiescent human neutrophils during incubation, 21% of the methionine (Met) residues were found to be oxidized. However, the portion of oxidized Met in extracellular proteins increased to 66% after stimulating the cells with zymosan and to 75% after stimulation with phorbol myristate acetate (PMA). Generation of such high levels of oxidized Met in native proteins by activated neutrophils has, so far, not been observed. The presence of superoxide dismutase during incubation of PMA-stimulated cells produced a negligible effect on methionine oxidation, while the presence of catalase resulted in a methionine suifoxide (Met(O)) content of only 28% in the released proteins. It is proposed that the conversion of Met to Met(O) in these proteins predominantly occurs by action of the myeloperoxidase/ H2O2/Cl− system in the extracellular space.

A gamma-crystallin has been purified by a two-step column chromatography from an extract of water soluble lens proteins from (101/ E1xC3H /E1)F1 mice. About 17% of the water soluble lens protein in normal mice is represented by this gamma-crystallin. The protein has been shown to be absent in cataractous lenses of Nop /+ mice after isoelectric focusing of water soluble lens proteins. It has a MW of 20,000. Amino acid analysis reveals the occurrence of eight cystein residues, which is considered to be high compared to other crystallins. The protein might play an important role in cataractogenesis.

Addition of 1 mM sulfite1 to a culture ofLactobacillus malii orLeuconostoc mesenteroides at pH 4.0 caused a rapid drop of the ATP content. At pH 6.0, the sulfite-stimulated depletion of the ATP level was somewhat diminished compared to the effect observed at pH 4.0. Incubation of the bacteria in the log phase with 2 mM sulfite at pH 5.0 prevented growth completely. Cells ofLeuconostoc mesenteroides in the log phase, incubated with 2 mM sulfite for 2 h at pH 5.0, showed a nearly normal growth after shifting to a sulfite-free medium. Cells ofLactobacillus malii, treated under the same conditions with sulfite, multiplied significantly slower in a fresh medium, as compared to untreated cells.