Richard Tessadri

In vitro evaluation of the toxicity induced by nickel soluble and particulate forms in human airway epithelial cells

Epidemiological studies show that exposure to nickel (Ni) compounds is associated with a variety of pulmonary adverse health effects, such as lung inflammation, fibrosis, emphysema and tumours. However, the mechanisms leading to pulmonary toxicity are not yet fully elucidated. In the current study we used Calu-3, a well differentiated human bronchial cell line, to investigate in vitro the effect of Ni in soluble form (NiCl(2)) and in the form of micro-sized Ni particles on the airway epithelium. For this purpose, we evaluated the effect of Ni compounds on the epithelial barrier integrity by monitoring the transepithelial electrical resistance (TEER) and on oxidative stress pathways by measuring reactive oxygen species (ROS) formation and induction of stress-inducible genes. Our results showed that exposure to NiCl(2) and Ni particles resulted in a disruption of the epithelial barrier function observed by alterations in TEER, which occurred prior to the decrease in cell viability. Moreover, Ni compounds induced oxidative stress associated with ROS formation and up-regulation of the stress-inducible genes, Metallothionein 1X (MT1X), Heat shock protein 70 (HSP70), Heme oxygenase-1 (HMOX-1), and gamma-glutamylcysteine synthetase (γGCS). Furthermore, we have demonstrated that the induced effects by Ni compounds can be partially attributed to the increase in Ni ions (Ni(2+)) intracellular levels.

Environmental changes in an alpine lake (Gossenköllesee, austria) over the last two centuries – the influence of air temperature on biological parameters

Changes in microfossils (diatoms, chrysophytes, chironomids and cladocera remains), geochemistry and deposition of atmospheric pollutants have been investigated in the sediment records of the alpine lake Gossenköllesee (Tyrol, Austria) spanning the last two centuries. The sediment records were compared with seasonal and annual air temperature trends calculated for the elevation (2417 m a.s.l.) and the geographical position (47° 13′46′′N, 11° 00′51′′E) of the lake, and with precipitation records available since 1866 from Innsbruck. Temperature trends followed a 20–30 year oscillation between cold and warm periods. Regarding long-term changes, temperature trends showed a U-shaped trend between 1780 and 1950, followed by a steep increase since 1975.Physical, geochemical, and organic parameters were not controlled by air temperature. Among the biological records only diatoms and chrysophytes reacted to air temperature changes: the relative abundance of planktonic diatoms increased during warm periods and changes in mean annual alpine air temperature explained 36.5% of their variation. The relation between abundance of seasonal stomatocyst types and air temperature varied on two different time scales: while summer stomatocysts were influenced by short term temperature fluctuations, the autumn stomatocysts were affected only by the long term changes. Other biological parameters exhibited a constant species composition (chironomids, pigments) or changes were small and independent of temperature (cladocera). Spheroidal carbonaceous fly-ash particles, and trends in Pb and Cr indicated increasing deposition of atmospheric pollutants but had no detectable effects on the biological parameters either. In respect to temperature variations over the last 200 years, this alpine lake is much less sensitive than expected and has thus to be regarded as a well buffered site. However, temperature alone is not sufficient to understand changes in species composition and other biogeochemical processes with unknown historical patterns might have affected species composition more strongly.

Conformational polymorphism in aripiprazole: Preparation, stability and structure of five modifications

Five phase-pure modifications of the antipsychotic drug aripiprazole were prepared and characterized by thermal analysis, vibrational spectroscopy and X-ray diffractometry. All modifications can be produced from solvents, form I additionally by heating of form X degrees to approximately 120 degrees C (solid-solid transformation) and form III by crystallization from the melt. Thermodynamic relationships between the polymorphs were evaluated on the basis of thermochemical data and visualized in a semi-schematic energy/temperature diagram. At least six of the ten polymorphic pairs are enantiotropically and two monotropically related. Form X degrees is the thermodynamically stable modification at 20 degrees C, form II is stable in a window from about 62-77 degrees C, and form I above 80 degrees C (high-temperature form). Forms III and IV are triclinic (

EMP-AMPH—a hypercard program determine the name of an amphibole for electron microprobe analysis according to the international mineralogical association scheme

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Trace element investigations in kidney stone patients.

), I and X degrees are monoclinic (P2(1)) and form II orthorhombic (Pna2(1)). Each polymorph exhibits a distinct molecular conformation, and there are two fundamental N-H

AMPH-IMA97: a hypercard program to determine the name of an amphibole from electron microprobe and wet chemical analyses

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Copper oxide nanoparticle toxicity profiling using untargeted metabolomics.

O hydrogen bond synthons (catemers and dimers). Hirshfeld surface analysis was employed to display differences in intermolecular short contacts. A high kinetic stability was observed for three metastable polymorphs which can be categorized as suitable candidates for the development of solid dosage forms.

Pt/ceria thin film model catalysts after high-temperature reduction: a (HR)TEM study

Abstract The program EMP-AMPH permits the input, editing, and calculation of an amphibole structural formula from Electron Microprobe Analysis (EMPA) data and determines the specific name with the prefixes and adjectives. It includes autosaving of data, search routines and other database functions. EMP-AMPH is an interactive program written in Hypertext and is designed to correspond to the Macintosh interface. In conjunction with the amphibole-software, a colored amphibole classification chart, based on the IMA nomenclature has been designed and is presented for the first time.

Technology and photoluminescence of GaAs micro- and nanocrystallites

31 different trace elements were analyzed in 24 kidney stones using the atomic absorption method. Where a significant trace element content in the concrements was detected, blood, urine and hair from the stone patients were investigated with respect to their trace element concentrations. In calcium stones mainly Fe, Pb, Sr and Zn and in organic stones As, Fe and Zn were found. No correlation could be found between the trace element content in stones, blood and urine. The hair of a woman with high As content in her stone contained a normal As concentration.

Poly(N-vinylimidazole/ethylene glycol dimethacrylate) for the purification and isolation of phenolic acids.

In 1997, the International Mineralogical Association (IMA) revised the amphibole naming scheme making it necessary to amend the previous EMP-AMPH Macintosh program to the new rules. The AMPH-IMA97 program allows single input or automatic input of as many amphibole analyses as are available following a set input format. There are three options for calculation scheme of amphibole analysis: (1) complete chemical analyses can be calculated to 24(O, OH, F, Cl); (2) analyses with determined FeO and Fe2O3 but without H2O can be calculated to 23(O) and (3) electron microprobe analyses with only total Fe determined and without H2O can be calculated to 23(O) with IMA97-recommended normalization for Fe 3+ and Fe 2+ values. To test the program, over 500 analyses were calculated using the three options. The first comprehensive test of the third option successfully estimated Fe 2+ (R 2 =0.88), but became less successful for Fe 3+ (R 2 =0.42) estimation. Problems in the normalization of Mn 3+ - and Mn 2+ -bearing amphiboles and in the IMA97 sodic amphibole classification procedure emerged for Mn-rich amphiboles. This necessitated the proposal and implementation with the program of a simplified sodic amphibole classification scheme. A new coloured amphibole classification chart accompanies the program. # 2001 Elsevier Science Ltd. All rights reserved.