1,347 research outputs found
The natural organosulfur compound dipropyltetrasulfide prevents HOCL-induced systemic sclerosis in the mouse
PublishedArticleIntroduction: The aim of this study was to test the naturally occurring organosulfur compound dipropyltetrasulfide (DPTTS) found in plants, which has antibiotic and anti-cancer properties, as a treatment of HOCl-induced systemic sclerosis in the mouse. Methods: The pro-oxidative, anti-proliferative and cytotoxic effects of DPTTS were evaluated ex vivo on fibroblasts from normal and HOCl-mice. In vivo, the anti-fibrotic and immunomodulating properties of DPTTS were evaluated in the skin and lungs of HOCl-mice. Results: H2O2 production was higher in fibroblasts derived from HOCl-mice than in normal fibroblasts (P<0.05). DPTTS did not increase H2O2 production in normal fibroblasts, but DPTTS dose-dependently increased H2O2 production in HOCl-fibroblasts (P<0.001 with 40ÎŒM DPTTS). Because H2O2 reached a lethal threshold in cells from HOCl-mice, the anti-proliferative, cytotoxic and pro-apoptotic effects of DPTTS were significantly higher in HOCl-fibroblasts than for normal fibroblasts. In vivo, DPTTS decreased dermal thickness (P<0.001), collagen content in skin (P<0.01) and lungs (P<0.05), SMA (P<0.01) and pSMAD2/3 (P<0.01) expression in skin, formation of advanced oxidation protein products and anti-DNA topoisomerase-1 antibodies in serum (P<0.05) versus untreated HOCl- mice. Moreover, in HOCl-mice, DPTTS reduced splenic B cell counts (P<0.01), the proliferative rates of B-splenocytes stimulated by lipopolysaccharide (P<0.05) and T-splenocytes stimulated by anti-CD3/CD28 mAb (P<0.001). Ex vivo, it also reduced the production of IL-4 and IL-13 by activated T cells (P<0.05 in both cases). Conclusions: The natural organosulfur compound DPTTS prevents skin and lung fibrosis in the mouse through the selective killing of diseased fibroblasts and its immunomodulating properties. DPTTS may be a potential treatment of Systemic sclerosis.This work was supported by European Communityâs Seventh Framework Programme (FP7/2007-2013) under grant agreement 215009 RedCat for financial support. The authors are grateful to Ms Agnes for her excellent typing of the manuscript
Trends in Insecticide Resistance in Natural Populations of Malaria Vectors in Burkina Faso, West Africa: 10 Yearsâ Surveys
International audienc
The worldwide change in the behavior of interest rates and prices in 1914
This paper evaluates the role of the destruction of the gold standard and the founding of the Federal Reserve, both of which occured in 1914, in contributing to observed changes in the behavior of interest rates and prices after 1914. The paper presents a model of policy coordination in which the introduction of the Fed stabilizes interest rates, even it the gold standard remains intact, and it offers empirical evidence that the dismantling of the gold standard did not play a crucial role in precipitating the changes in interest rate behavior.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/27286/1/0000305.pd
Assessing the effect of flood restoration on surfaceâsubsurface interactions in Rohrschollen Island (Upper Rhine river â France) using integrated hydrological modeling and thermal infrared imaging
Rohrschollen Island is an artificial island of the large Upper Rhine river
whose geometry and hydrological dynamics are the result of engineering works
during the 19th and 20th centuries. Before its channelization, the Rhine
river was characterized by an intense hydromorphological activity which
maintained a high level of biodiversity along the fluvial corridor. This
functionality considerably decreased during the two last centuries.
In 2012, a restoration project was launched to reactivate typical alluvial
processes, including bedload transport, lateral channel dynamics, and
surfaceâsubsurface water exchanges. An integrated hydrological model has been
applied to the area of Rohrschollen Island to assess the efficiency of the
restoration regarding surface and subsurface flows. This model is calibrated
using measured piezometric heads. Simulated patterns of water exchanges
between the surface and subsurface compartments of the island are checked
against the information derived from thermal infrared (TIR) imaging. The simulated
results are then used to better understand the evolutions of the
infiltrationâexfiltration zones over time and space and to determine the
physical controls of surfaceâsubsurface interactions on the hydrographic
network of Rohrschollen Island. The use of integrated hydrological modeling
has proven to be an efficient approach to assess the efficiency of
restoration actions regarding surface and subsurface flows.</p
Packing and Hausdorff measures of stable trees
In this paper we discuss Hausdorff and packing measures of random continuous
trees called stable trees. Stable trees form a specific class of L\'evy trees
(introduced by Le Gall and Le Jan in 1998) that contains Aldous's continuum
random tree (1991) which corresponds to the Brownian case. We provide results
for the whole stable trees and for their level sets that are the sets of points
situated at a given distance from the root. We first show that there is no
exact packing measure for levels sets. We also prove that non-Brownian stable
trees and their level sets have no exact Hausdorff measure with regularly
varying gauge function, which continues previous results from a joint work with
J-F Le Gall (2006).Comment: 40 page
Fine-scale Modeling of Bristlecone Pine Treeline Position in the Great Basin, USA
Great Basin bristlecone pine (Pinus longaeva) and foxtail pine (Pinus balfouriana) are valuable paleoclimate resources due to their longevity and climatic sensitivity of their annually-resolved rings. Treeline research has shown that growing season temperatures limit tree growth at and just below the upper treeline. In the Great Basin, the presence of precisely dated remnant wood above modern treeline shows that the treeline ecotone shifts at centennial timescales tracking long-term changes in climate; in some areas during the Holocene climatic optimum treeline was 100 meters higher than at present. Regional treeline position models built exclusively from climate data may identify characteristics specific to Great Basin treelines and inform future physiological studies, providing a measure of climate sensitivity specific to bristlecone and foxtail pine treelines. This study implements a topoclimatic analysisâusing topographic variables to explain patterns in surface temperatures across diverse mountainous terrainâto model the treeline position of three semi-arid bristlecone and/or foxtail pine treelines in the Great Basin as a function of growing season length and mean temperature calculated from in situ measurements. Results indicate: (1) the treeline sites used in this study are similar to other treelines globally, and require a growing season length of between 147â153 days and average temperature ranging from 5.5°Câ7.2°C, (2) site-specific treeline position models may be improved through topoclimatic analysis and (3) treeline position in the Great Basin is likely out of equilibrium with the current climate, indicating a possible future upslope shift in treeline position
Salmonella enterica serotype Virchow associated with human infections in Switzerland: 2004-2009
BACKGROUND: Salmonellosis is one of the most important foodborne diseases and a major threat to public health. Salmonella serotype Virchow ranks among the top five serovars in Europe. METHOD: A total of 153 strains isolated from different patients from 2004 through 2009 in Switzerland were further characterized by (i) assessing phenotypic antibiotic resistance profiles using the disk diffusion method and (ii) by genotyping using pulsed-field gel electrophoresis (PFGE) after macrorestriction with XbaI in order to evaluate strain relationship. RESULTS: The relative frequency of S. Virchow among other Salmonella serovars varied between 4th to 8th rank. The annual incidence ranged from 0.45/100'000 in 2004 to 0.40/100'000 in 2009. A total of 48 strains (32%) were resistant to one to 3 antimicrobials, 54 strains (36%) displayed resistance patterns to more than three antibiotics. No trend was identifiable over the years 2004 to 2009. We found a high prevalence (62%) of nalidixic acid resistant strains, suggesting an equally high rate of decreased fluoroqionolone susceptibility, whereas intermediate resistance to ciprofloxacin was negligible. Two strains were extended spectrum ÎČ-lactamase (ESBL) producers. Analysis of PFGE patterns uncovered a predominant cluster (similarity coefficient above 80%) consisting of 104 of the 153 strains. CONCLUSION: The worldwide increase of antibiotic resistances in Salmonella is an emerging public health problem. For Switzerland, no clear trend is identifiable over the years 2004 to 2009 for S. Virchow. Antimicrobial susceptibility and resistance profiles varied considerably within this period. Nevertheless, the situation in Switzerland coincided with findings in other European countries. Genotyping results of this strain collection revealed no evidence for an undetected outbreak within this time period
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