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991.
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Interferon regulatory factor-4 binding protein (IBP) is a novel upstream activator of Rho GTPases. Our previous studies have shown that ectopic expression of IBP was correlated with malignant behaviors of human breast cancer cells, and invasive human breast cancer had high expression of IBP that promoted the proliferation of these cells. However, it remains unknown whether autophagy inhibition contributes to IBP-mediated tumorigenesis. In this study, we for the first time, reported that upregulation of IBP expression significantly suppressed the autophagy of breast cancer cells, and downregulation of IBP expression markedly induced autophagy of these cells. Further investigation revealed that IBP effectively counteracted autophagy by directly activating mammalian target of rapamycin complex 2 (mTORC2) and upregulating phosphorylation of Akt on ser473 and FOXO3a on Thr32. Moreover, IBP-mediated suppression of autophagy was dependent on mTORC2/Akt/FOXO3a signaling pathway. Finally, our results demonstrated that IBP-mediated breast cancer cell growth in vitro and in vivo was strongly correlated with suppression of mTORC2-dependent autophagy. These findings suggest that the anti-autophagic property of IBP has an important role in IBP-mediated tumorigenesis, and IBP may serve as an attractive target for treatment of breast cancer. 相似文献
994.
不同功能位点介导α干扰素的免疫调节和中枢镇痛作用 总被引:6,自引:0,他引:6
细胞因子α干扰素(IFNα)具有中枢镇痛作用。抗内源性阿片肽血清与IFNα能发生明显的交叉反应,提示IFNα与内源性阿片肽之间存在着共同的抗原决定基。采用基因定点突变技术,获得系列IFNα突变体,并分别测定其免疫学活性和镇痛能力。结果显示,IFNα突变体Y129S-IFNα免疫学活性显著下降,但仍然保留了很强的镇痛能力,阿片受体拮抗纳洛酮能够阻断Y129S-IFNα的镇痛作用。实验结果表明,IFN 相似文献
995.
GIS-based distributed model for simulating runoff and sediment load in the Malian River Basin 总被引:3,自引:0,他引:3
Huang Y. F. Chen X. Huang G. H. Chen Bing Zeng G. M. Li J. B. Xia J. 《Hydrobiologia》2003,494(1-3):127-134
GIS-based modeling is an effective approach for reflecting spatially-varied complexities in watershed systems. In this study, a GIS-aided distributive hydrological model was developed to simulate runoff and sediment transport in a loess-plateau context with semi-arid climate, sparse vegetation, and serious soil erosion. The model was then applied to a case study in the Malian River Basin, which is one of the largest catchments in the middle reach of the Yellow River. Based on the GIS technique, the DEM of the study basin was successfully used to delineate the stream network and extract information of catchment characteristics. The results show satisfactory accuracy for runoff simulation. Especially, the integrated soil-erosion and hydrological models can be used for simulating both runoff and sediment loads, which provide a useful decision-support tool for water resources management and pollution control. This study is an attempt to develop a distributed rainfall-runoff model for river basins in the loess plateau region. The developed model can also be extended to larger basins. Further works of field survey and investigation would be helpful for better calibrating critical parameters and thus improving performance of the developed model. 相似文献
996.
997.
David Engel Anita Williams Woolley Lisa X. Jing Christopher F. Chabris Thomas W. Malone 《PloS one》2014,9(12)
Recent research with face-to-face groups found that a measure of general group effectiveness (called “collective intelligence”) predicted a group’s performance on a wide range of different tasks. The same research also found that collective intelligence was correlated with the individual group members’ ability to reason about the mental states of others (an ability called “Theory of Mind” or “ToM”). Since ToM was measured in this work by a test that requires participants to “read” the mental states of others from looking at their eyes (the “Reading the Mind in the Eyes” test), it is uncertain whether the same results would emerge in online groups where these visual cues are not available. Here we find that: (1) a collective intelligence factor characterizes group performance approximately as well for online groups as for face-to-face groups; and (2) surprisingly, the ToM measure is equally predictive of collective intelligence in both face-to-face and online groups, even though the online groups communicate only via text and never see each other at all. This provides strong evidence that ToM abilities are just as important to group performance in online environments with limited nonverbal cues as they are face-to-face. It also suggests that the Reading the Mind in the Eyes test measures a deeper, domain-independent aspect of social reasoning, not merely the ability to recognize facial expressions of mental states. 相似文献
998.
C. Dang X. de Montaudouin J. Bald F. Jude N. Raymond L. Lanceleur I. Paul-Pont N. Caill-Milly 《Hydrobiologia》2009,630(1):139-148
Knowledge of temporal variation in nearshore Laurentian Great Lakes fish assemblages is important for understanding species–habitat
associations, how abiotic and biotic influences vary temporally, and when sampling should occur. Using spring and fall seining
data from Lake Erie beaches, we compared day and night fish assemblages and tested for differences among sampling periods.
Beaches were utilized by a diverse collection of Lake Erie basin fishes (one-third of known species). During all sampling
periods, catches were dominated by cyprinid species (53–91%), and by invertivores and planktivorous fishes. Diel differences
were detected in abundance, species richness and assemblage structure. Multivariate analyses (canonical analysis of principal
coordinates) indicated that season had a larger influence on fish assemblage structure than diel period. Given observed temporal
variation in assemblage structure, studies of Laurentian Great Lakes beach fishes should be restricted to a single time period
(e.g. day-time spring sampling), or adopt sampling designs that permit diel period and season to be included as factors in
analyses. Second, the large seasonal variation in assemblage composition combined with higher night species richness indicates
that night sampling during both spring and fall would be the most efficient and comprehensive approach for beach fish inventory.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Handling editor: J. Trexler 相似文献
999.
Taneja M Bols PE Van de Velde A Ju JC Schreiber D Tripp MW Levine H Echelard Y Riesen J Yang X 《Biology of reproduction》2000,62(1):206-213
Juvenile calf oocytes represent an untapped source of germ plasm for reproduction. Reports on the developmental competence of calf oocytes have been controversial. In this research, oocytes were recovered after gonadotropin stimulation from Holstein calves (N = 10) at 2-3 mo of age (2-mo cycle) and again at 4-5 mo of age (4-mo cycle). The in vitro developmental competence was measured, and prestimulation follicle numbers (for 2-mo cycle) and poststimulation follicle numbers (both cycles) were obtained. The number of antral follicles doubled after stimulation (23.4 +/- 6.1 vs. 55.1 +/- 16.1) for the 2-mo cycle and for the 4-mo cycle (47.4 +/- 12.4). The number of follicles observed prior to stimulation in the 2-mo cycle was found to be highly correlated with the poststimulation oocyte recovery for both collection cycles (r = 0.95, 2-mo cycle; r = 0.81, 4-mo cycle). The majority (90-96%) of recovered oocytes were found to be usable for in vitro maturation and fertilization; of these, 41-42% cleaved and 10-11% developed to morulae or blastocysts. Eighty-four in vitro-produced embryos were transferred to synchronized recipients and resulted in 11 pregnancies, leading to 7 live (4 males, 3 females) and 2 dead (one male, one female) calves at full term. No significant differences were observed between the 2-mo and 4-mo collection cycles; however, 73% of the total pregnancies resulted from the 2-mo cycle. All pregnancies resulted from embryos of high-responding donors. The high correlation between the number of follicles prior to stimulation and the poststimulation response suggests the possibility of screening calves prior to stimulation for routine embryo production. 相似文献
1000.