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991.
Qian Lu Chong Wang Rong Pan Xinghua Gao Zhifeng Wei Yufeng Xia Yue Dai 《Journal of cellular biochemistry》2013,114(5):1009-1019
Histamine, a major mediator present in mast cells that is released into the extracellular milieu upon degranulation, is well known to possess a wide range of biological activities in several classic physiological and pathological processes. However, whether and how it participates in angiogenesis remains obscure. In the present study, we observed its direct and synergistic action with basic fibroblast growth factor (bFGF), an important inducer of angiogenesis, on in vitro angiogenesis models of endothelial cells. Data showed that histamine (0.1, 1, 10 µM) itself was absent of direct effects on the processes of angiogenesis, including the proliferation, migration, and tube formation of endothelial cells. Nevertheless, it could concentration‐dependently enhance bFGF‐induced angiogenesis as well as production of vascular endothelial growth factor (VEGF) from endothelial cells. The synergistic effect of histamine on VEGF production could be reversed by pretreatments with diphenhydramine (H1‐receptor antagonist), SB203580 (selective p38 mitogen‐activated protein kinase (MAPK) inhibitor) and L ‐NAME (nitric oxide synthase (NOS) inhibitor), but not with cimetidine (H2‐receptor antagonist) and indomethacin (cyclooxygenase (COX) inhibitor). Moreover, histamine could augment bFGF‐incuced phosphorylation and degradation of IκBα, a key factor accounting for the activation and translocation of nuclear factor κB (NF‐κB) in endothelial cells. These findings indicated that histamine was able to synergistically augment bFGF‐induced angiogenesis, and this action was linked to VEGF production through H1‐receptor and the activation of endothelial nitric oxide synthase (eNOS), p38 MAPK, and IκBα in endothelial cells. J. Cell. Biochem. 114: 1009–1019, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
992.
993.
Wen‐juan Wang Xiao‐xing Shi Yi‐wen Liu Yi‐qing He Ying‐zhi Wang Cui‐xia Yang Feng Gao 《Journal of cellular biochemistry》2013,114(7):1695-1703
The F1F0 ATP synthase has recently become the focus of anti‐cancer research. It was once thought that ATP synthases were located strictly on the inner mitochondrial membrane; however, in 1994, it was found that some ATP synthases localized to the cell surface. The cell surface ATP synthases are involved in angiogenesis, lipoprotein metabolism, innate immunity, hypertension, the regulation of food intake, and other processes. Inhibitors of this synthase have been reported to be cytotoxic and to induce intracellular acidification. However, the mechanisms by which these effects are mediated and the molecular pathways that are involved remain unclear. In this study, we aimed to determine whether the inhibition of cell proliferation and the induction of cell apoptosis that are induced by inhibitors of the cell surface ATP synthase are associated with intracellular acidification and to investigate the mechanism that underlines the effects of this inhibition, particularly in an acidic tumor environment. We demonstrated that intracellular acidification contributes to the cell proliferation inhibition that is mediated by cell surface ATP synthase inhibitors, but not to the induction of apoptosis. Intracellular acidification is only one of the mechanisms of ecto‐ATP synthase‐targeted antitumor drugs. We propose that intracellular acidification in combination with the inhibition of cell surface ATP generation induce cell apoptosis after cell surface ATP synthase blocked by its inhibitors. A better understanding of the mechanisms activated by ecto‐ATP synthase‐targeted cancer therapies may facilitate the development of potent anti‐tumor therapies, which target this enzyme and do not exhibit clinical limitations. J. Cell. Biochem. 114: 1695–1703, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
994.
Estrogen receptor α (ERα) may play important roles in many estrogen physiological effects, but little is known about the fluctuation of ERα during the estrous cycle. In this study, the dynamic expression of ERα mRNA and protein in periodontal tissue during the estrous cycle were examined. Forty 12‐week‐old female rats were divided into four groups, based on the estrous cycle stage, and sacrificed. Immunohistochemistry and in situ hybridization were used to detect dynamic changes in ERα protein and mRNA in periodontal tissue during the estrous cycle, and data were analyzed by one‐way ANOVA and cosinor analysis for temporal patterns. Significant differences (p<0.05) were found in the expression of ERα protein and mRNA among the four groups. The expression of ERα protein and mRNA exhibited an infradian rhythm with a period of about 120 h (five days). The phase and amplitude differences between ERα protein and mRNA were not significant (p>0.05). The results suggest the expression of ERα is dynamic during the estrous cycle and that in the future chronobiologic methods should be used to study the mechanism of estrogen effect on periodontal tissue. 相似文献
995.
Puhong Gao Alexis M. Hattox Lauren M. Jones Asaf Keller 《Somatosensory & motor research》2013,30(3-4):191-198
Previous studies, based on qualitative observations, reported that lesions of the whisker motor cortex produce no deficits in whisking behavior. We used high-resolution optoelectronic recording methods to compare the temporal organization and kinematics of whisker movements before and after unilateral lesions of whisker motor cortex in rats. We now report that while the lesion did not abolish whisking, it significantly disrupted whisking kinematics, coordination, and temporal organization. Lesioned animals showed significant increases in the velocity and amplitude of whisker protractions contralateral to the lesions, as well as a reduction in the synchrony of whisker movements on the two sides of the face. There was a marked shift in the distribution of whisking frequencies, with reduction of activity in the 5–7?Hz bandwidth and increased activity at <?2?Hz. Disruptions of the normal whisking pattern were evident on both sides of the face, and the magnitude of these effects was proportional to the extent of the cortical ablation. We suggest that the observed deficits reflect an imbalance in cortical inputs to a brainstem central pattern generator. 相似文献
996.
Xuejun Yang Carol C. Baskin Jerry M. Baskin Ruiru Gao Fan Yang Lingling Wei Leilei Li Hongju He Zhenying Huang 《Oecologia》2013,173(4):1451-1458
Post-dispersal seed removal by animals can lead to extensive seed loss and thus is an important factor in structuring plant communities. However, we know much less about post-dispersal seed predation than about other forms of herbivory. Mucilage plays many ecological roles in adaptation of plants to diverse environments; nevertheless, until now the role of mucilage in ant-mediated seed movement remains largely hypothetical. We studied the role of mucilage in seed removal of Artemisia sphaerocephala by ants in Mu Us Sandland in Inner Mongolia, China. Messor aciculatus was the most active seed predator of Artemisia sphaerocephala. Time to first ant collecting (T 1st) of wet intact seeds was longest and significantly different from that for dry intact seeds, wet demucilaged seeds, and dry demucilaged seeds; number of seeds removed to ant nests was lowest for wet intact seeds. After they were collected by ants, 5 % of wet intact seeds were dropped during transport. Our results indicate that seed mucilage of Artemisia sphaerocephala may play a significant role in post-dispersal seed removal by (1) making seeds less attractive to ants, thus resulting in a delay of collection time; (2) forming a strong bond to soil particles, making it difficult for ants to remove seeds; and (3) making seeds more likely to be dropped during transport, thereby allowing them to escape from predation even after collection by ants. This study demonstrates the importance of mucilage in reducing seed removal by ants and thus in anchoring seeds of desert plants in the vicinity of mother plants. 相似文献
997.
998.
999.
Yi Wang Dianne Edwards Michael Bassett Hong‐He Xu Jiafei Xiao Qing Jiang Xiaole Zhang 《Palaeontology》2013,56(4):679-683
Pinnatiramosus qianensis Geng, 1986, is a plant with a complex, extensive pinnate branching system and pitted tracheids, collected from marine Lower Silurian (Llandovery; c. 430 Ma) rocks in Guizhou Province, China. It challenges long‐held theories on the origin and early evolution of vascular plants in the Silurian and Devonian. However, there is a hypothesis that the fossils were not syngenetic with the entombing rock, but were the rooting systems of much younger plants, probably of Permian age. New sections and collections of P. qianensis have been subjected to detailed analyses, which indicate that P. qianensis belongs to an early Permian (c. 285 Ma) rooting system growing down into lower Silurian rocks. 相似文献
1000.
The critical soil P levels for crop yield, soil fertility and environmental safety in different soil types 总被引:34,自引:0,他引:34
Zhaohai Bai Haigang Li Xueyun Yang Baoku Zhou Xiaojun Shi Boren Wang Dongchu Li Jianbo Shen Qing Chen Wei Qin Oene Oenema Fusuo Zhang 《Plant and Soil》2013,372(1-2):27-37