ABSTRACT
Precipitation patterns over Europe are largely controlled by atmospheric cyclones embedded in the general circulation of the mid-latitudes. This study evaluates the climatologic features of precipitation for selected regions in central Europe with respect to cyclone track types for 1959-2015, focusing on large-scale heavy precipitation. The analysis suggests that each of the cyclone track types is connected to a specific pattern of the upper level atmospheric flow, usually characterized by a major trough located over Europe. A dominant upper level cut-off low (COL) is found over Europe for strong continental (CON) and van Bebber's type (Vb) cyclones which move from the east and southeast into central Europe. Strong Vb cyclones revealed the longest residence times, mainly due to circular propagation paths. The central European cyclone precipitation climate can largely be explained by seasonal track-type frequency and cyclone intensity; however, additional factors are needed to explain a secondary precipitation maximum in early autumn. The occurrence of large precipitation totals for track events is strongly related to the track type and the region, with the highest value of 45% of all Vb cyclones connected to heavy precipitation in summer over the Czech Republic and eastern Austria. In western Germany, Atlantic winter cyclones are most relevant for heavy precipitation. The analysis of the top 50 precipitation events revealed an outstanding heavy precipitation period from 2006 to 2011 in the Czech Republic, but no gradual long-term change. The findings help better understand spatio-temporal variability of heavy precipitation in the context of floods and may be used for evaluating climate models.
ABSTRACT
Previous studies have indicated that volatile anaesthetics can attenuate the inflammatory response to lipopolysaccharide (LPS) and other proinflammatory stimuli in vitro and in vivo. Thus far, no studies are available on the influences of desflurane on the cytokine-release. We therefore aimed to investigate the effects of desflurane on the systemic and pulmonary release of proinflammatory cytokines in endotoxemic rats. Eighteen anaesthetized and ventilated Sprague-Dawley rats were randomly assigned to the following groups: LPS-only: Six animals received LPS (5 mg/kg, i.v.) with no further intervention. LPS-Desflurane: Six animals received continuous inhalation of 1MAC Desflurane before and during endotoxemia with LPS (5 mg/kg, i.v.). Sham: Six animals served as control without inhalation of desflurane and endotoxemia. After 4 h, levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta) and interleukin-6 (IL-6) in plasma and bronchoalveolar fluid were analyzed. Nitrite production as a readout for nitric oxide (NO) release from alveolar macrophages was measured by Griess assay. IkappaB-alpha degradation and iNOS-protein in macrophage homogenates were determined by Western Blotting. Inhalation of desflurane during endotoxemia showed a significant decrease in release of the proinflammatory cytokines TNF-alpha (-61%, P< or =0.05) and IL-1beta (-47%, P< or =0.05) in plasma as compared to LPS-only group, whereas the release of IL-6 was not significantly affected by desflurane. Within the lung, the NO-release was notably increased in supernatants of cultured alveolar macrophages from desflurane-group compared to both LPS-only and Sham group. IkappaB-alpha degradation in alveolar macrophages was impaired in the Desflurane-group as compared to the LPS-only group. Our data implicate that inhalation of 1MAC Desflurane during experimental endotoxemia differentially affects the inflammatory response in rats.
