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Pulmonic stenosis is a frequent congenital heart disease in dogs, and the treatment of choice is balloon valvuloplasty which is usually safe and successful. The authors describe for the first time a severe complication after balloon valvuloplasty in a five-month-old dog. After effective treatment, with a considerable drop in right ventricular pressures, the dog developed hypoxemia and dyspnea due to pulmonary edema. The dog underwent intensive care and symptoms improved after a few hours of oxygen therapy, continuous positive airway pressure, and furosemide. Although this event is rare, it could have a large impact on patient survival and should be considered in the treatment of severe pulmonary valve stenosis in the future. [ABSTRACT FROM AUTHOR]

Abstract: In 2003 the World Calibration Centre for volatile organic compounds (WCC-VOC) which forms part of the Global Atmosphere Watch (GAW) program coordinated the first comprehensive intercomparison exercise among the GAW-VOC community. The intercomparison focused on a synthetic C2–C11 VOC standard mixture in nitrogen (N2) and involved nine different stations/laboratories (10 instruments) from seven countries (Brazil, Canada [two labs], Czech Republic, Finland, Germany [two labs; three instruments], Ireland, and Slovakia), representing four measurement programs (GAW, EMEP, CAPMoN, LBA). These sites either run canister or online measurements. WCC-VOC provided each participant of the intercomparison exercise with standard gas canisters which contained 73 VOCs prepared and certified by the National Center for Atmospheric Research (NCAR), Boulder. The participating laboratories were expected to identify and quantify as many compounds of the WCC-VOC standard canister as possible based on their routine identification and calibration methods. The primary objective of this first intercomparison was to examine the current performance status of the analytical facilities of each laboratory and to check whether the results meet the Data Quality Objectives (DQO) developed by WCC-VOC. An additional objective was to establish a ranking of properly determined compounds among all laboratories in order to identify compounds which could be most accurately determined by all laboratories. Due to the variety of sampling and analytical methods among the participants both the number of identified species (16–150 VOCs) and their proper quantification differed largely. Focusing on a subset of 28 VOCs recognized as primary GAW target compounds the results show that the DQOs for repeatability are met in most cases. However for the deviation from the WCC-VOC reference values the picture is different. For some VOCs the concentrations differed significantly among the different laboratories. In terms of both uncertainty and repeatability a significant number of atmospherically relevant VOCs (e.g. propane, propylene, isoprene, and benzene) are properly determined by most labs. However, difficulties occur with other important VOCs (e.g. acetylene, i-pentane, toluene). From this subset of VOC results it appears imperative to strengthen harmonization procedures particular with regard to real air samplings. These processes have been initiated and include more frequent intercomparisons also covering ambient air samples, individual performance audits, and a future networkwide calibration standard. [Copyright &y& Elsevier]

The plasma membrane enzyme gamma-glutamyltransferase (GGT) is regarded as critical for the maintenance of intracellular levels of glutathione (GSH). GGT expression has been implicated in drug resistance through elevation of intracellular GSH. The dependence of intracellular GSH on GGT expression was not conclusively ascertained. The present study was designed to investigate the role of GGT and of intracellular GSH levels in modulating proliferation and sensitivity to cisplatin of melanoma cells. GGT transfection resulted in increased growth, both in vitro and in tumour xenografts. In addition, GGT-transfected cells exhibited reduced sensitivity to cisplatin associated with lower DNA platination. A decrease in intracellular GSH levels, rather than an increase, was observed in GGT-transfected cells; moreover, in cysteine-deficient conditions, the expression of GGT did not provide transfected cells with the ability of utilising extracellular GSH. In conclusion, these results indicate that GGT activity confers a growth advantage unrelated with intracellular glutathione supply, and are consistent with the interpretation that cisplatin resistance is the consequence of modifications of cellular pharmacokinetics as a result of extracellular drug inactivation by thiol metabolites originated by GGT-mediated GSH cleavage. [ABSTRACT FROM AUTHOR]

Methods of digital close-range photogrammetry allow for manifold real 3-D measurements in dynamic processes. Based on the acquisition of multi-camera digital image sequences, image analysis with subpixel accuracy image measurement operators, photogrammetric multi-image matching and point determination techniques, strict geometric modeling of complex environments and thorough system calibration techniques, time-resolved accurate 3-D coordinates of a large number of objects in a scene can be determined fully automatically. The paper will first give a short review on basic principles of digital photogrammetry and discuss the application and accuracy potential. After that, practical examples will be given from several breadboard experiments conducted in the frame of the ESA Technological Research and Development Programme to show the applicability of the technique to typical experiments in the field of fluid physics. These experiments focus on the investigation of experiments on Marangoni convection; they include the determination of 3-D velocity fields near a hanging drop within a fluid matrix and the observation of the tangential tension on the boundary surface by measuring changes in shape and/or position of liquid bodies like drops, bubbles or liquid columns in a fluid matrix. [Copyright &y& Elsevier]