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131.
Florian Raub Hubert Höfer Ludger Scheuermann Ricardo Miranda de Britez Roland Brandl 《Studies on Neotropical Fauna and Environment》2013,48(3):158-174
In the Atlantic Forest in Brazil, where no more primary forests exist, the value of secondary forests for biodiversity conservation is becoming more and more important. We studied the spiders in a relatively well-preserved region of the Mata Atlântica, where the matrix of the landscape is still forest. We addressed the contribution of different spatial levels including forest stages to total diversity and analyzed the patterns by additive partitioning of beta diversity on genus and morphospecies level and for different sampling methods. Beta diversity was strongly based on turnover, not on gain/loss. All spatial levels (sample, stage, area, locality) contributed more to beta diversity than expected, without stronger influence of stage. Patterns were consistent for both identification levels and all methods. We conclude that in this landscape the protection of large areas encompassing all forest stages, without special attention to old-growth, is the best way to conserve the regional species richness. 相似文献
132.
Katja Hattar Rajkumar Savai Florentine S. B. Subtil Jochen Wilhelm Anja Schmall Dagmar S. Lang Torsten Goldmann Bastian Eul Gabriele Dahlem Ludger Fink Ralph-Theo Schermuly Gamal-Andre Banat Ulf Sibelius Friedrich Grimminger Ekkehard Vollmer Werner Seeger Ulrich Grandel 《Cancer immunology, immunotherapy : CII》2013,62(2):309-320
Lung cancer is frequently complicated by pulmonary infections which may impair prognosis of this disease. Therefore, we investigated the effect of bacterial lipopolysaccharides (LPS) on tumor proliferation in vitro in the non-small cell lung cancer (NSCLC) cell line A549, ex vivo in a tissue culture model using human NSCLC specimens and in vivo in the A549 adenocarcinoma mouse model. LPS induced a time- and dose-dependent increase in proliferation of A549 cells as quantified by MTS activity and cell counting. In parallel, an increased expression of the proliferation marker Ki-67 and cyclooxygenase (COX)-2 was detected both in A549 cells and in ex vivo human NSCLC tissue. Large amounts of COX-2-derived prostaglandin (PG)E2 were secreted from LPS-stimulated A549 cells. Pharmacological interventions revealed that the proliferative effect of LPS was dependent on CD14 and Toll-like receptor (TLR)4. Moreover, blocking of the epidermal growth factor receptor (EGFR) also decreased LPS-induced proliferation of A549 cells. Inhibition of COX-2 activity in A549 cells severely attenuated both PGE2 release and proliferation in response to LPS. Synthesis of PGE2 was also reduced by inhibiting CD14, TLR4 and EGFR in A549 cells. The proliferative effect of LPS on A549 cells could be reproduced in the A549 adenocarcinoma mouse model with enhancement of tumor growth and Ki-67 expression in implanted tumors. In summary, LPS induces proliferation of NSCLC cells in vitro, ex vivo in human NSCLC specimen and in vivo in a mouse model of NSCLC. Pulmonary infection may thus directly induce tumor progression in NSCLC. 相似文献
133.
The microtubule (MT) network, an important part of the cytoskeleton, is constantly remodeled by alternating phases of growth and shrinkage of individual filaments. Plus-end tracking proteins (+TIPs) interact with the MT and in many cases alter its dynamics. Although it is established that some +TIPs modify MT dynamics by increasing rescues, the plus-end tracking mechanism is still under debate. We present a model for MT dynamics in which a rescue factor is dynamically added to the filament during growth. As a consequence, the filament shows aging behavior that should be experimentally accessible and thus allow one to exclude some hypothesized models regarding the inclusion of rescue factors at the MT plus end. This result is not limited to +TIPs and can be extended to any kind of mechanism shifting the parameters of dynamic instability. Additionally, we show that the cell geometry has a strong influence on the quantitative results. 相似文献
134.
Activation of the classical IκB kinases (IKKα and IKKβ) was previously shown to contribute to obesity-induced inflammation and insulin resistance. Using knockout mice, we investigated whether the related isoform IKKε plays a similar metabolic role.IKKε−/− mice had reduced body weight, leptin levels, as well as higher insulin sensitivity when kept on chow diet. However, inflammatory parameters, measured in liver, adipose tissue and plasma, were either unaltered or showed a trend toward up-regulation (liver NF-κB activity, TNFα and IL-1β expression). Chronic feeding of a high fat diet induced equal obesity and insulin resistance, and similarly induced inflammatory markers, in IKKε−/− and wild-type mice, indicating that under high caloric conditions the inflammatory and metabolic effects of IKKε deficiency were overridden.Taken together, our data indicate that IKKε does not have general pro-inflammatory properties in liver and adipose tissue, and suggest that reduced adiposity is the primary mechanism for improved insulin sensitivity in IKKε−/− mice on chow diet. 相似文献
135.
Jure Acimovic Anita L?vgren-Sandblom Maria Olin Zeina Ali Maura Heverin Rebecca Schüle Ludger Sch?ls Bj?rn Fischler Peter Fickert Michael Trauner Ingemar Bj?rkhem 《PloS one》2013,8(7)
24S- and 27-hydroxycholesterol (24OHC and 27OHC) are potent regulators of different biochemical systems in vitro and are the major circulating oxysterols. A small fraction of these oxysterols has been reported to be sulphated but there are no detailed studies. We considered the possibility that sulphatation is a protective mechanism preventing accumulation of free oxysterols. Using an accurate assay we found the sulphated fraction of 24OHC and 27OHC in circulation of adults to be less than 15% of total. In two patients with a mutation in CYP7B1 and markedly increased levels of 27OHC the sulphated fraction was 8% and 10% respectively. Infants with severe neonatal cholestasis had however markedly increased sulphate fraction of the above oxysterols. In untreated mice the degree of sulphatation of 24OHC and 27OHC in serum varied between 0 and 16%. Similar degree of sulphatation was found in two mouse models with markedly increased levels of 27OHC and 24OHC respectively. Bile duct ligated mice had higher levels of oxysterols than sham-operated controls but the sulphate fraction was not increased. We conclude that a primary increase in the levels of the oxysterols due to increased synthesis or reduced metabolism in adults and mice does not induce increased sulphatation. 相似文献
136.
Ludger Klewes Rhea Vallente Eric Dupas Carolin Brand Dietrich Grün Amanda Guffei Chirawadee Sathitruangsak Julius A. Awe Alexandra Kuzyk Daniel Lichtensztejn Pille Tammur Tiiu Ilus Anu Tamm Mari Punab Morel Rubinger Adebayo Olujohungbe Sabine Mai 《Translational oncology》2013,6(6):749-IN36
Multiple myeloma (MM) is preceded by monoclonal gammopathy of undetermined significance (MGUS). Up to date, it is difficult to predict an individual's time to disease progression and the treatment response. To examine whether the nuclear telomeric architecture will unravel some of these questions, we carried out. Three-dimensional (3D) telomere analysis on samples from patients diagnosed with MGUS and MM, as well as from patients who went into relapse. Telomere signal intensity, number of telomere aggregates, nuclear volume, and the overall nuclear telomere distribution (a/c ratio) were analyzed. The telomeric profiles allowed for the differentiation of the disease stages. The telomeric profiles of myeloma cells obtained from blood and bone marrow aspirates were identical. Based on this study, we discuss the use of 3D telomere profiling as a potential future tool for risk stratification and personalized treatment decisions. 相似文献
137.
Philippe de Timary Mariana Cordovil de Sousa Uva Catherine Deno?l Ludger Hebborn Marc Derely Martin Desseilles Olivier Luminet 《PloS one》2013,8(8)
Context
In order to understand how certain personality traits influence the relation between depression symptoms and craving for alcohol, trait self-consciousness (trait SC) was examined during a withdrawal and detoxification program.Methods
Craving (Obsessive and Compulsive Drinking Scale), depressive state (Beck Depression Inventory) and trait SC (Revised Self-Consciousness Scale) were assessed in alcohol-dependent inpatients (DSM-IV, N = 30) both at the beginning (T1: day 1 or 2) and at the end (T2: day 14 to18) of protracted withdrawal during rehabilitation.Results
A significant decrease in craving and depressive symptoms was observed from T1 to T2, while SC scores remained stable. At both times, strong positive correlations were observed between craving and depression. Moreover, regression analyses indicated that trait SC significantly moderated the impact of depression on cravings for alcohol.Limitations
This study was performed on a relatively small sample size. Administration of medications during detoxification treatment can also be a confounding factor. Finally, craving could have been evaluated through other types of measurements.Conclusions
During protracted withdrawal, alcohol craving decreased with the same magnitude as depressive mood. Depressive symptoms were related to alcohol craving but only among patients with high trait SC scores. Our results suggest that metacognitive approaches targeting SC could decrease craving and, in turn, prevent future relapses. 相似文献138.
Dominic Franck Torsten Kniess Jörg Steinbach Sabine Zitzmann-Kolbe Matthias Friebe Ludger M. Dinkelborg Keith Graham 《Bioorganic & medicinal chemistry》2013,21(3):643-652
The [18F]fluorocyclobutyl group has the potential to be a metabolically stable prosthetic group for PET tracers. The synthesis of the radiolabeling precursor cis-cyclobutane-1,3-diyl bis(toluene-4-sulfonate) 8 was obtained from epibromohydrin in 7 steps (2% overall yield). The radiolabeling of this precursor 8 and its conjugation to l-tyrosine as a model system was successfully achieved to give the new non-natural amino acid 3-[18F]fluorocyclobutyl-l-tyrosine (L-3-[18F]FCBT) [18F]17 in 8% decay-corrected yield from the non-carrier-added [18F]fluoride. L-3-[18F]FCBT was investigated in vitro in different cancer cell lines to determine the uptake and stability. The tracer [18F]17 showed a time dependent uptake into different tumor cell lines (A549, NCI-H460, DU145) with the best uptake of 5.8% injected dose per 5 × 105 cells after 30 min in human lung carcinoma cells A549. The stability of L-3-[18F]FCBT in human and rat plasma and the stability of the non-radioactive L-3-FCBT in rat hepatocytes were both found to be excellent. These results show that the non-natural amino acid L-3-[18F]FCBT is a promising metabolically stable radiotracer for positron emission tomography. 相似文献
139.
140.
Stefan Bayer Ludger Keilig Dominik Kraus Manfred Grüner Helmut Stark Sebastian Mues Norbert Enkling 《Gerodontology》2011,28(3):221-226
Gerodontology 2010; doi: 10.1111/j.1741‐2358.2009.00352.x Influence of the lubricant and the alloy on the wear behaviour of attachments Objectives: Wear of attachments leads to a loss of retention and reduces the function of overdentures. This study evaluated the retention force changes of an attachment system for overdentures. The influence of the lubricant and the alloy on wear constancy was examined. Methods: Cylindrical anchors of the Dalbo®‐Z system were tested (Cendres+Métaux SA). Three groups of alloy‐lubricant combinations were generated 1.Elitor®/NaCl‐solution (EN) 2.Elitor®/Glandosane®aquadest. (EG) and 3.Valor®/Glandosane®/aquadest. (VG). Ten samples of each group were subjected to 10 000 insertion–separation cycles. Results: For the EN‐group, this led to a large increase in retention force. The EG‐ and VG‐group showed a constant decrease after an initial increase in retention force at the beginning of the wear simulation. The change of the alloy caused no statistically significant differences. The use of a more viscous lubricant reduced the retention force increase significantly. Conclusions: The use of a lubricant which simulates clinical conditions is an absolute need for wear simulation because the retention force changes are influenced enormously. The change of the alloy at the Dalbo®‐Z system did not influence the wear behaviour. As a slight decrease in retention force was recorded, it is useful for an attachment system to allow compensation with an adjustable matrix. 相似文献