283 research outputs found

    Decelerated spreading in degree-correlated networks

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    While degree correlations are known to play a crucial role for spreading phenomena in networks, their impact on the propagation speed has hardly been understood. Here we investigate a tunable spreading model on scale-free networks and show that the propagation becomes slow in positively (negatively) correlated networks if nodes with a high connectivity locally accelerate (decelerate) the propagation. Examining the efficient paths offers a coherent explanation for this result, while the kk-core decomposition reveals the dependence of the nodal spreading efficiency on the correlation. Our findings should open new pathways to delicately control real-world spreading processes

    Measuring degree-degree association in networks

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    The Pearson correlation coefficient is commonly used for quantifying the global level of degree-degree association in complex networks. Here, we use a probabilistic representation of the underlying network structure for assessing the applicability of different association measures to heavy-tailed degree distributions. Theoretical arguments together with our numerical study indicate that Pearson's coefficient often depends on the size of networks with equal association structure, impeding a systematic comparison of real-world networks. In contrast, Kendall-Gibbons' τb\tau_{b} is a considerably more robust measure of the degree-degree association

    Canine-Derived Cosmid Probes Containing Microsatellites Can Be Used in Physical Mapping of Arctic Fox (Alopex lagopus) and Chinese Raccoon Dog (Nyctereutes procyonoides procyonoides) Genomes

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    Rapid development of the canine marker genome map facilitates genome mapping of other Canidae species. In this study we present chromosomal localization of 18 canine-derived cosmid probes containing microsatellites in the arctic fox (Alopex lagopus) and Chinese raccoon dog (Nyctereutes procyonoides procyonoides) genomes by the use of fluorescence in situ hybridization (FISH). The chromosome localizations in the arctic fox are in general agreement with data obtained from comparative genome maps of the dog and the fox. However, our studies showed that the order of the loci on some chromosomes was changed during karyotype evolution. Therefore, we suggest that small intrachromosomal rearrangements took plac

    Clinical determinants of the PR interval duration in Swiss middle-aged adults: The CoLaus/PsyCoLaus study.

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    Prolonged PR interval (PRi) is associated with adverse outcomes. However, PRi determinants are poorly known. We aimed to identify the clinical determinants of the PRi duration in the general population. Some clinical data are associated with prolonged PRi. Cross-sectional study conducted between 2014 and 2017. Electrocardiogram-derived PRi duration was categorized into normal or prolonged (>200 ms). Determinants were identified using stepwise logistic regression, and results were expressed as multivariable-adjusted odds ratio (OR) (95% confidence interval). A further analysis was performed adjusting for antiarrhythmic drugs, P-wave contribution to PRi duration, electrolytes (kalemia, calcemia, and magnesemia), and history of cardiovascular disease. Overall, 3655 participants with measurable PRi duration were included (55.6% females; mean age 62 ± 10 years), and 330 (9.0%) had prolonged PRi. Stepwise logistic regression identified male sex (OR 1.41 [1.02-1.97]); aging (65-74 years: OR 2.29 [1.61-3.24], and ≥ 75 years: OR 4.21 [2.81-6.31]); increased height (per 5 cm, OR 1.15 [1.06-1.25]); hypertension (OR 1.37 [1.06-1.77]); and hs troponin T (OR 1.67 [1.15-2.43]) as significantly and positively associated, and high resting heart rate (≥70 beats/min, OR 0.43 [0.29-0.62]) as negatively associated with prolonged PRi. After further adjustment, male sex, aging and increased height remained positively, and high resting heart rate negatively associated with prolonged PRi. Hypertension and hs troponin T were no longer associated. In a sample of the Swiss middle-aged population, male sex, aging and increased height significantly increased the likelihood of a prolonged PRi duration, whereas a high resting heart rate decreased it

    Clinically relevant concentrations of lidocaine and ropivacaine inhibit TNFα-induced invasion of lung adenocarcinoma cells in vitro by blocking the activation of Akt and focal adhesion kinase

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    BACKGROUND Matrix-metalloproteinases (MMP) and cancer cell invasion are crucial for solid tumour metastasis. Important signalling events triggered by inflammatory cytokines, such as tumour necrosis factor α (TNFα), include Src-kinase-dependent activation of Akt and focal adhesion kinase (FAK) and phosphorylation of caveolin-1. Based on previous studies where we demonstrated amide-type local anaesthetics block TNFα-induced Src activation in malignant cells, we hypothesized that local anaesthetics might also inhibit the activation and/or phosphorylation of Akt, FAK and caveolin-1, thus attenuating MMP release and invasion of malignant cells. METHODS NCI-H838 lung adenocarcinoma cells were incubated with ropivacaine or lidocaine (1 nM-100 µM) in absence/presence of TNFα (20 ng ml(-1)) for 20 min or 4 h, respectively. Activation/phosphorylation of Akt, FAK and caveolin-1 were evaluated by Western blot, and MMP-9 secretion was determined by enzyme-linked immunosorbent assay. Tumour cell migration (electrical wound-healing assay) and invasion were also assessed. RESULTS Ropivacaine (1 nM-100 μM) and lidocaine (1-100 µM) significantly reduced TNFα-induced activation/phosphorylation of Akt, FAK and caveolin-1 in NCI-H838 cells. MMP-9 secretion triggered by TNFα was significantly attenuated by both lidocaine and ropivacaine (half-maximal inhibitory concentration [IC50]=3.29×10(-6) M for lidocaine; IC50=1.52×10(-10) M for ropivacaine). The TNFα-induced increase in invasion was completely blocked by both lidocaine (10 µM) and ropivacaine (1 µM). CONCLUSIONS At clinically relevant concentrations both ropivacaine and lidocaine blocked tumour cell invasion and MMP-9 secretion by attenuating Src-dependent inflammatory signalling events. Although determined entirely in vitro, these findings provide significant insight into the potential mechanism by which local anaesthetics might diminish metastasi
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