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991.
992.
In the hand laterality task participants judge the handedness of visually presented stimuli--images of hands shown in a variety of postures and views--and indicate whether they perceive a right or left hand. The task engages kinaesthetic and sensorimotor processes and is considered a standard example of motor imagery. However, in this study we find that while motor imagery holds across egocentric views of the stimuli (where the hands are likely to be one's own), it does not appear to hold across allocentric views (where the hands are likely to be another person's). First, we find that psychophysical sensitivity, d', is clearly demarcated between egocentric and allocentric views, being high for the former and low for the latter. Secondly, using mixed effects methods to analyse the chronometric data, we find high positive correlation between response times across egocentric views, suggesting a common use of motor imagery across these views. Correlations are, however, considerably lower between egocentric and allocentric views, suggesting a switch from motor imagery across these perspectives. We relate these findings to research showing that the extrastriate body area discriminates egocentric ('self') and allocentric ('other') views of the human body and of body parts, including hands.  相似文献   
993.
Zheng Y  Brady OA  Meng PS  Mao Y  Hu F 《PloS one》2011,6(6):e21023
Progranulin haplo-insufficiency is a main cause of frontotemporal lobar degeneration (FTLD) with TDP-43 aggregates. Previous studies have shown that sortilin regulates progranulin trafficking and is a main determinant of progranulin level in the brain. In this study, we mapped the binding site between progranulin and sortilin. Progranulin binds to the beta-propeller region of sortilin through its C-terminal tail. The C-terminal progranulin fragment is fully sufficient for sortilin binding and progranulin C-terminal peptide displaces progranulin binding to sortilin. Deletion of the last 3 residues of progranulin (QLL) abolishes its binding to sortilin and also sortilin dependent regulation of progranulin trafficking. Since progranulin haplo-insufficiency results in FTLD, these results may provide important insights into future studies of progranulin trafficking and signaling and progranulin based therapy for FTLD.  相似文献   
994.
The analysis of dynamic events in the tumor microenvironment during cancer progression is limited by the complexity of current in vivo imaging models. This is coupled with an inability to rapidly modulate and visualize protein activity in real time and to understand the consequence of these perturbations in vivo. We developed an intravital imaging approach that allows the rapid induction and subsequent depletion of target protein levels within human cancer xenografts while assessing the impact on cell behavior and morphology in real time. A conditionally stabilized fluorescent E-cadherin chimera was expressed in metastatic breast cancer cells, and the impact of E-cadherin induction and depletion was visualized using real-time confocal microscopy in a xenograft avian embryo model. We demonstrate the assessment of protein localization, cell morphology and migration in cells undergoing epithelial-mesenchymal and mesenchymal-epithelial transitions in breast tumors. This technique allows for precise control over protein activity in vivo while permitting the temporal analysis of dynamic biophysical parameters.  相似文献   
995.
Global knowledge about the spatial distribution of species is orders of magnitude coarser in resolution than other geographically-structured environmental datasets such as topography or land cover. Yet such knowledge is crucial in deciphering ecological and evolutionary processes and in managing global change. In this review, we propose a conceptual and cyber-infrastructure framework for refining species distributional knowledge that is novel in its ability to mobilize and integrate diverse types of data such that their collective strengths overcome individual weaknesses. The ultimate aim is a public, online, quality-vetted 'Map of Life' that for every species integrates and visualizes available distributional knowledge, while also facilitating user feedback and dynamic biodiversity analyses. First milestones toward such an infrastructure have now been implemented.  相似文献   
996.

Aims

To develop test methods and evaluate the survival of Bacillus anthracis ?Sterne and Bacillus thuringiensis Al Hakam spores after exposure to hot, humid air.

Methods and Results

Spores (>7 logs) of both strains were dried on six different test materials. Response surface methodology was employed to identify the limits of spore survival at optimal test combinations of temperature (60, 68, 77°C), relative humidity (60, 75, 90%) and time (1, 4, 7 days). No spores survived the harshest test run (77°C, 90% r.h., 7 days), while > 6·5 logs of spores survived the mildest test run (60°C, 60% r.h., 1 day). Spores of both strains inoculated on nylon webbing and polypropylene had greater survival rates at 68°C, 75% r.h., 4 days than spores on other materials. Electron microscopy showed no obvious physical damage to spores using hot, humid air, which contrasted with pH‐adjusted bleach decontamination.

Conclusions

Test methods were developed to show that hot, humid air effectively inactivates B. anthracis ?Sterne and B. thuringiensis Al Hakam spores with similar kinetics.

Significance and Impact of the Study

Hot, humid air is a potential alternative to conventional chemical decontamination.  相似文献   
997.
998.
We provide evidence that type I IFN-induced STAT activation is diminished in cells with targeted disruption of the Rictor gene, whose protein product is a key element of mTOR complex 2. Our studies show that transient or stable knockdown of Rictor or Sin1 results in defects in activation of elements of the STAT pathway and reduced STAT-DNA binding complexes. This leads to decreased expression of several IFN-inducible genes that mediate important biological functions. Our studies also demonstrate that Rictor and Sin1 play essential roles in the generation of the suppressive effects of IFNα on malignant erythroid precursors from patients with myeloproliferative neoplasms. Altogether, these findings provide evidence for critical functions for Rictor/Sin1 complexes in type I IFN signaling and the generation of type I IFN antineoplastic responses.  相似文献   
999.
1. An assay, based on competition between adenosine 3':5'-cyclic monophosphate (cyclic AMP) and cyclic [(3)H]AMP for binding to a rabbit skeletal muscle protein, has been used to measure tissue contents of cyclic AMP. The assay has a sensitivity of 0.05pmol of cyclic AMP. Cyclic GMP and cyclic CMP have 0.5%, and cyclic IMP 6.5%, of the ability of cyclic AMP to displace cyclic [(3)H]AMP from binding protein; AMP, ADP and ATP have no effect. 2. By using this method, the cyclic AMP content of ox pituitary slices exposed to prostaglandin was determined; release of growth hormone was measured by radioimmunoassay. 3. Release of growth hormone was increased by 45min incubation in 1mum-prostaglandin E(2) in the absence of theophylline, or in 10nm-prostaglandin E(2), 0.1mum-prostaglandin A(1) or 1mum-prostaglandin B(1) in the presence of 0.5mm-theophylline. 4. Pituitary cyclic AMP content was increased by 10min incubation in 1mum-prostaglandin E(2) in the absence of theophylline, or in 0.1mum-prostaglandin E(2) in the presence of 0.5mm-theophylline. 5. The maximum increase in cyclic AMP content was observed 10min, and significant changes in growth hormone release 30min, after introduction of prostaglandin E(2). 6. The increase in pituitary cyclic AMP content, but not in the rate of release of growth hormone, was observed in the absence of external Ca(2+). 7. The stimulation of release of growth hormone by prostaglandin was decreased by preincubation of tissue for 2h in colchicine (100mum) or cytochalasin B (10mug/ml). 8. These results support the suggestion that increased release of growth hormone after treatment with prostaglandin is the result of increased tissue cyclic AMP content, and possibly involves a microfilamentous or microtubular protein.  相似文献   
1000.
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