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211.
Children’s interpretations of sentences containing focus particles do not seem adult-like until school age. This study investigates how German 4-year-old children comprehend sentences with the focus particle ‘nur’ (only) by using different tasks and controlling for the impact of general cognitive abilities on performance measures. Two sentence types with ‘only’ in either pre-subject or pre-object position were presented. Eye gaze data and verbal responses were collected via the visual world paradigm combined with a sentence-picture verification task. While the eye tracking data revealed an adult-like pattern of focus particle processing, the sentence-picture verification replicated previous findings of poor comprehension, especially for ‘only’ in pre-subject position. A second study focused on the impact of general cognitive abilities on the outcomes of the verification task. Working memory was related to children’s performance in both sentence types whereas inhibitory control was selectively related to the number of errors for sentences with ‘only’ in pre-subject position. These results suggest that children at the age of 4 years have the linguistic competence to correctly interpret sentences with focus particles, which–depending on specific task demands–may be masked by immature general cognitive abilities. 相似文献
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Roel J. T. Mocking Anja Lok Johanna Assies Maarten W. J. Koeter Ieke Visser Henricus G. Ruhé Claudi L. H. Bockting Aart H. Schene 《PloS one》2013,8(12)
Background
Fatty acid (FA)-alterations may mediate the mutual association between Major Depressive Disorder (MDD) and cardiovascular disease (CVD). However, etiology of observed FA-alterations in MDD and CVD remains largely unclear. An interesting candidate may be a mutation in the fatty acid–binding protein 2 (FABP2)-gene, because it regulates dietary FA-uptake. Therefore, we aimed to test the hypotheses that in MDD-patients the FABP2 Ala54Thr-polymorphism would be (I) more prevalent than in sex- and age-matched controls, (II) associated with observed alterations in FA-metabolism, and (III) associated with CVD-risk factor waist circumference.Methods
We measured concentrations of 29 different erythrocyte FAs, FABP2-genotype, and waist circumference in recurrent MDD-patients and matched never-depressed controls.Results
FABP2-genotype distribution did not significantly differ between the 137 MDD-patients and 73 matched controls. However, patients with the Ala54Thr-polymorphism had (I) higher concentrations of especially eicosadienoic acid (C20:2ω6; P=.009) and other 20-carbon FAs, and associated (II) lower waist circumference (P=.019). In addition, FABP2-genotype effects on waist circumference in patients seemed (I) mediated by its effect on C20:2ω6, and (II) different from controls.Conclusions
Although Ala54Thr-polymorphism distribution was not associated with recurrent MDD, our results indicate that FABP2 may play a role in the explanation of observed FA-alterations in MDD. For Ala54Thr-polymorphism patients, potentially adaptive conversion of increased bioavailable dietary precursors into eicosadienoic acid instead of arachidonic acid might be related to a low waist circumference. Because this is the first investigation of these associations, replication is warranted, preferably by nutrigenetic studies applying lipidomics and detailed dietary assessment. 相似文献214.
CpG-induced tyrosine phosphorylation occurs via a TLR9-independent mechanism and is required for cytokine secretion 总被引:2,自引:0,他引:2 下载免费PDF全文
Sanjuan MA Rao N Lai KT Gu Y Sun S Fuchs A Fung-Leung WP Colonna M Karlsson L 《The Journal of cell biology》2006,172(7):1057-1068
Toll-like receptors (TLRs) recognize molecular patterns preferentially expressed by pathogens. In endosomes, TLR9 is activated by unmethylated bacterial DNA, resulting in proinflammatory cytokine secretion via the adaptor protein MyD88. We demonstrate that CpG oligonucleotides activate a TLR9-independent pathway initiated by two Src family kinases, Hck and Lyn, which trigger a tyrosine phosphorylation–mediated signaling cascade. This cascade induces actin cytoskeleton reorganization, resulting in cell spreading, adhesion, and motility. CpG-induced actin polymerization originates at the plasma membrane, rather than in endosomes. Chloroquine, an inhibitor of CpG-triggered cytokine secretion, blocked TLR9/MyD88-dependent cytokine secretion as expected but failed to inhibit CpG-induced Src family kinase activation and its dependent cellular responses. Knock down of Src family kinase expression or the use of specific kinase inhibitors blocked MyD88-dependent signaling and cytokine secretion, providing evidence that tyrosine phosphorylation is both CpG induced and an upstream requirement for the engagement of TLR9. The Src family pathway intersects the TLR9–MyD88 pathway by promoting the tyrosine phosphorylation of TLR9 and the recruitment of Syk to this receptor. 相似文献
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As part of the expanding cultivation of renewable primary products, oilseed rape has become a prominent part of the agricultural
landscape of many European countries. However, the ecological impacts of increasing cultivation of oilseed rape have received
little attention so far. In this study, we provide the first systematic investigation of the suitability of oilseed rape as
a habitat for the Bluethroat (Luscinia svecica cyanecula), an endangered and highly specialized bird species. We conducted territorial mapping and a habitat analysis, revealing the
distinct habitat requirements of L. s. cyanecula in oilseed rape fields over three breeding seasons. The soil type was identified as the crucial factor for habitat occupancy.
It acts as a surrogate for soil moisture and this in turn decisively influences food availability. Ditches can further improve
habitat quality, whereas reed is not a necessary structure, although it is a regular feature in the primary habitat of the
Bluethroat. Occupied oilseed rape stands were structurally different from the semi-natural reed habitat, but provided similar
essential habitat requirements, such as shelter from predation and moist, bare soil. Our results clearly demonstrate the utilization
of oilseed rape by a rare and threatened wetland bird species and suggest that this crop may act as a secondary habitat. 相似文献
217.
Saturated free fatty acid (FFA) is a major source of metabolic stress that activates the c-Jun NH(2)-terminal kinase (JNK). This FFA-stimulated JNK pathway is relevant to hallmarks of metabolic syndrome, including insulin resistance. Here we used gene ablation studies in mice to demonstrate a central role for mixed-lineage protein kinases (MLK) in this signaling pathway. Saturated FFA causes protein kinase C (PKC)-dependent activation of MLK3 that subsequently causes increased JNK activity by a mechanism that requires the MAP kinase kinases MKK4 and MKK7. Loss of PKC, MLK3, MKK4, or MKK7 expression prevents FFA-stimulated JNK activation. Together, these data establish a signaling pathway that mediates effects of metabolic stress on insulin resistance. 相似文献
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Willem H. van de Poll Anja Eggert Anita G. J. Buma Anneke M. Breeman 《Journal of phycology》2001,37(1):30-38
The sensitivity to UV-B radiation (UVBR: 280–315 nm) was tested for littoral (Palmaria palmata[L.] O. Kuntze, Chondrus crispus Stackhouse) and sublittoral (Phyllophora pseudoceranoides S. G. Gmelin, Rhodymenia pseudopalmata[Lamouroux] Silva, Phycodrys rubens[L.] Batt, Polyneura hilliae[Greville] Kylin) red macrophytes from Brittany, France. Algal fragments were subjected to daily repeated exposures of artificial UVBR that were realistic for springtime solar UVBR at the water surface in Brittany. Growth, DNA damage, photoinhibition, and UV-absorbing compounds were monitored during 2 weeks of PAR + UV-A radiation (UVAR) + UVBR, whereas PAR + UVAR and PAR treatments were used as controls. The littoral species showed a higher UV tolerance than the sublittoral species. After 2 weeks, growth of P. palmata and C. crispus was not significantly affected by UVBR, and DNA damage, measured as the number of cyclobutane-pyrimidine dimers per 106 nucleotides, was negligible. Photoinhibition, determined as the decline in optimal quantum yield, was low and decreased during the course of the experiment, coinciding with the production of UV-absorbing compounds in these species. In contrast, no UV-absorbing compounds were induced in the sublittoral species. Growth rates of P. pseudoceranoides and R. pseudopalmata were reduced by 40% compared with the PAR treatment. Additionally, constant levels of DNA damage and pronounced photoinhibition were observed after the UVBR treatments. Growth was completely halted for Phycodrys rubens and Polyneura hilliae, whereas DNA damage accumulated in the course of the experiment. Because Phycodrys rubens and Polyneura hilliae showed the same degree of photoinhibition as the other sublittoral species, it appears that the accumulation of DNA damage may have been responsible for the complete inhibition of growth. The results suggest an important role of DNA repair pathways in determining the UV sensitivity in red macrophytes. 相似文献
220.