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141.
Korabecny J Musilek K Zemek F Horova A Holas O Nepovimova E Opletalova V Hroudova J Fisar Z Jung YS Kuca K 《Bioorganic & medicinal chemistry letters》2011,21(21):6563-6566
Cholinesterase inhibitors are, so far, the only successful strategy for the symptomatic treatment of Alzheimer's disease. Tacrine (THA) is a potent acetylcholinesterase inhibitor that was used in the treatment of Alzheimer's disease for a long time. However, the clinical use of THA was hampered by its low therapeutic index, short half-life and liver toxicity. 7-Methoxytacrine (7-MEOTA) is equally pharmacological active compound with lower toxicity compared to THA. In this Letter, the synthesis, biological activity and molecular modelling of elimination by-product isolated during synthesis of 7-MEOTA based bis-alkylene linked compound is described. 相似文献
142.
Van Praet JT Smith V Haspeslagh M Degryse N Elewaut D De Keyser F 《Arthritis research & therapy》2011,13(1):R35
Introduction
The aims of the present study were to identify histopathological parameters which are linked to local clinical skin disease at two distinct anatomical sites in systemic sclerosis (SSc) patients with skin involvement (limited cutaneous systemic sclerosis (lcSSc) or diffuse cutaneous systemic sclerosis (dcSSc)) and to determine the sensitivity of SSc specific histological alterations, focusing on SSc patients without clinical skin involvement (limited SSc (lSSc)). 相似文献143.
Ruttens A Boulet J Weyens N Smeets K Adriaensen K Meers E Van Slycken S Tack F Meiresonne L Thewys T Witters N Carleer R Dupae J Vangronsveld J 《International journal of phytoremediation》2011,13(Z1):194-207
Phytoremediation, more precisely phytoextraction, has been placed forward as an environmental friendly remediation technique, that can gradually reduce increased soil metal concentrations, in particular the bioavailable fractions. The aim of this study was to investigate the possibilities of growing willows and poplars under short rotation coppice (SRC) on an acid, poor, sandy metal contaminated soil, to combine in this way soil remediation by phytoextraction on one hand, and production of biomass for energy purposes on the other. Above ground biomass productivities were low for poplars to moderate for willows, which was not surprising, taking into account the soil conditions that are not very favorable for growth of these trees. Calculated phytoextraction efficiency was much longer for poplars than these for willows. We calculated that for phytoextraction in this particular case it would take at least 36 years to reach the legal threshold values for cadmium, but in combination with production of feedstock for bioenergy processes, this type of land use can offer an alternative income for local farmers. Based on the data of the first growing cycle, for this particular case, SRC of willows should be recommended. 相似文献
144.
145.
Large-scale land conversion for agriculture in Brazilian Amazonia is occurring at persistently high rates. Basin-wide net land use and land cover changes imply substantially different situations between distinct regions and states due to different agricultural policies. This research used eight landscape metrics to quantify and investigate the spatial patterns of cattle pasture and cropland throughout the states of Pará, Mato Grosso, Rondônia, and Amazonas. These metrics were patch density (DEN), mean patch size (MPS), largest patch index (LPI), mean edge density (MED), mean twist number (TWI), corrected perimeter-to-area ratio (CPA), fractal dimension (FDI), and fragmentation index (FRG). A total of 1852 patches were analyzed, originating from 86 samples in 71 different plots, covering a total of 177,500 km2 throughout all four states.Principal component analysis showed a partial overlap in the spatial pattern of agricultural patches between all states. The largest percentage of variance was explained by patch area metrics, which can be related to the different approaches in agricultural policies, but no clear division between the states was identified in this dimension. The metrics quantifying patch shape were de facto independent of deforestation area, and related to the second principal component axis. Although some overlap in this dimension was present as well, these metrics proved a possible measure for discerning the patterns of agriculture attached to a certain state. Different land use policies are hypothesized to lead to more heterogeneity in landscape patterns in an early stage, yet the increasing influence of both cropland and pasture agriculture eventually leads to more uniform landscapes in which spatial differences gradually disappear. 相似文献
146.
147.
Settles M Etzrodt M Kosanke K Schiemann M Zimmermann A Meier R Braren R Huber A Rummeny EJ Weissleder R Swirski FK Wildgruber M 《PloS one》2011,6(10):e25197
Objective
To explore the capacity of human CD14+CD16++ and CD14++CD16- monocytes to phagocyte iron-oxide nanoparticles in vitro.Methods
Human monocytes were labeled with four different magnetic nanoparticle preparations (Ferumoxides, SHU 555C, CLIO-680, MION-48) exhibiting distinct properties and cellular uptake was quantitatively assessed by flow cytometry, fluorescence microscopy, atomic absorption spectrometry and Magnetic Resonance Imaging (MRI). Additionally we determined whether cellular uptake of the nanoparticles resulted in phenotypic changes of cell surface markers.Results
Cellular uptake differed between the four nanoparticle preparations. However for each nanoparticle tested, CD14++CD16- monocytes displayed a significantly higher uptake compared to CD14+CD16++ monocytes, this resulted in significantly lower T1 and T2 relaxation times of these cells. The uptake of iron-oxide nanoparticles further resulted in a remarkable shift of expression of cell surface proteins indicating that the labeling procedure affects the phenotype of CD14+CD16++ and CD14++CD16- monocytes differently.Conclusion
Human monocyte subsets internalize different magnetic nanoparticle preparations differently, resulting in variable loading capacities, imaging phenotypes and likely biological properties. 相似文献148.
149.
Background
Transcranial magnetic stimulation (TMS) has become an important experimental tool for exploring the brain''s functional anatomy. As TMS interferes with neural activity, the hypothetical function of the stimulated area can thus be tested. One unresolved methodological issue in TMS experiments is the question of how to adequately calibrate stimulation intensities. The motor threshold (MT) is often taken as a reference for individually adapted stimulation intensities in TMS experiments, even if they do not involve the motor system. The aim of the present study was to evaluate whether it is reasonable to adjust stimulation intensities in each subject to the individual MT if prefrontal regions are stimulated prior to the performance of a cognitive paradigm.Methods and Findings
Repetitive TMS (rTMS) was applied prior to a working memory task, either at the ‘fixed’ intensity of 40% maximum stimulator output (MSO), or individually adapted at 90% of the subject''s MT. Stimulation was applied to a target region in the left posterior middle frontal gyrus (pMFG), as indicated by a functional magnetic resonance imaging (fMRI) localizer acquired beforehand, or to a control site (vertex). Results show that MT predicted the effect size after stimulating subjects with the fixed intensity (i.e., subjects with a low MT showed a greater behavioral effect). Nevertheless, the individual adaptation of intensities did not lead to stable effects.Conclusion
Therefore, we suggest assessing MT and account for it as a measure for general cortical TMS susceptibility, even if TMS is applied outside the motor domain. 相似文献150.
Van Nieuwerburgh F Soetaert S Podshivalova K Ay-Lin Wang E Schaffer L Deforce D Salomon DR Head SR Ordoukhanian P 《PloS one》2011,6(10):e26969
Here we demonstrate a method for unbiased multiplexed deep sequencing of RNA and DNA libraries using a novel, efficient and adaptable barcoding strategy called Post Amplification Ligation-Mediated (PALM). PALM barcoding is performed as the very last step of library preparation, eliminating a potential barcode-induced bias and allowing the flexibility to synthesize as many barcodes as needed. We sequenced PALM barcoded micro RNA (miRNA) and DNA reference samples and evaluated the quantitative barcode-induced bias in comparison to the same reference samples prepared using the Illumina TruSeq barcoding strategy. The Illumina TruSeq small RNA strategy introduces the barcode during the PCR step using differentially barcoded primers, while the TruSeq DNA strategy introduces the barcode before the PCR step by ligation of differentially barcoded adaptors. Results show virtually no bias between the differentially barcoded miRNA and DNA samples, both for the PALM and the TruSeq sample preparation methods. We also multiplexed miRNA reference samples using a pre-PCR barcode ligation. This barcoding strategy results in significant bias. 相似文献