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981.
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
982.
983.
12 h rotating shifts are common in high‐tech industries in Taiwan. The aim of this longitudinal study was to evaluate the effect of the disruption of circadian rhythms by the shift schedule on menstrual cycle length (MCL) and regularity of female workers at an optoelectronic company in Taiwan. We recruited females who worked rotating shifts in a clean room environment as the shift‐work group and female office workers who worked normal business hours as the comparison group. Every participant recorded their MCL for each menstruation cycle up to eight consecutive months prospectively and provided demographic characteristics, reproductive history, and menstrual characteristics. We collected data on 1,135 and 117 menstruation cycles in the shift‐work (n=280) and comparison groups (n=49). Whereas the two groups had similar group means for MCL and number of menstrual bleeding days, the prevalence of menstrual cycle irregularity (cycles<25 or>35 days) was higher in the shift‐work group (p=0.04). Univariate and multivariate logistic regression analyses demonstrated that rotating shift work was an independent predictor of menstrual cycle irregularity (odds ratio=1.71, 95% confidence interval: 1.03–2.88) after adjusting for shift‐work history, employment duration, coffee consumption, and pre‐employment menstrual cycle irregularity. Although further study is required to confirm our findings plus to explore prevention and control measures, our data indicate rotating shift work can increase the risk of MCL irregularity. 相似文献
984.
Cheng X. Li Xin Wei Lu Lu Jeremy L. Peirce Robert W. Williams 《Somatosensory & motor research》2013,30(3):141-150
We measured the combined area of posterior medial barrel subfield (PMBSF) and anterior lateral barrel subfield (ALBSF) areas in four common inbred strains (C3H/HeJ, A?/J, C57BL?/6J, DBA/2J), B6D2F1, and ten recombinant inbred (RI) strains generated from C57BL/6J and DBA/2J progenitors (BXD) as an initial attempt to examine the genetic influences underlying natural variation in barrel field size in adult mice. These two subfields are associated with the representation of the whisker pad and sinus hairs on the contralateral face. Using cytochrome oxidase labeling to visualize the barrel field, we measured the size of the combined subfields in each mouse strain. We also measured body weight and brain weight in each strain. We report that DBA/2J mice have a larger combined PMBSF/ALBSF area (6.15?±?0.10?mm2,?n?=?7) than C57BL?/6J (5.48?±?0.13?mm2,?n?=?10), C3H/HeJ (5.37?±?0.16?mm2,?n?=?10), and A/J mice (5.04?±?0.09?mm2,?n?=?15), despite the fact that DBA/2J mice have smaller average brain and body sizes. This finding may reflect dissociation between systems that control brain size with those that regulate barrel field area. In addition, BXD strains (average n?=?4) and parental strains showed considerable and continuous variation in PMBSF/ALBSF area, suggesting that this trait is polygenic. Furthermore, brain, body, and cortex weights have heritable differences between inbred strains and among BXD strains. PMBSF/ALBSF pattern appears similar among inbred and BXD strains, suggesting that somatosensory patterning reflects a common plan of organization. This data is an important first step in the quantitative genetic analysis of the parcellation of neocortex into diverse cytoarchitectonic zones that vary widely within and between species, and in identifying the genetic factors underlying barrel field size using quantitative trait locus (QTL) analyses. 相似文献
985.
Root pressure and plasma membrane intrinsic protein (PIP) availability in the xylem have been recognized to participate in the refilling of embolized conduits, yet integration of the two mechanisms has not been reported in the same plant. In this study, 4‐month‐old seedlings of a hybrid poplar (Populus alba × Populus glandulosa) clone 84K were subjected to two contrasting soil‐water treatments, with the drought treatment involving withholding of water for 17 days to reduce the soil‐water content to 10% of the saturated field capacity, followed by a re‐watering cycle. The percentage loss of stem hydraulic conductance (PLC) sharply increased, and stomatal conductance and photosynthesis declined in response to drought stress; these processes were gradually restored following the subsequent re‐watering. Embolism was most severe in the middle portions of the stem, followed by the basal and top portions of the stems of seedlings subjected to drought stress and subsequent re‐watering. Although drought stress eliminated root pressure, re‐watering partially restored it in a short period of time. The expression of PIP genes in the xylem was activated by drought stress, and some PIP genes were further stimulated in the top portion after re‐watering. The dynamics of root pressure and differential expression of PIP genes along the stem coincided with changes in PLC, suggesting that root pressure and PIPs work together to refill the embolized vessels. On the basis of the recovery dynamics in PLC and gsmax (maximum stomatal conductance) after re‐watering, the stomatal closure and xylem cavitation exhibited fatigue due to drought stress. 相似文献
986.
Pengshan Zhao Fei Liu Bo Zhang Xin Liu Bing Wang Jiao Gong Guanzhong Yu Miao Ma Yujian Lu Jing Sun Zhenyu Wang Pengfei Jia Heng Liu 《Physiologia plantarum》2013,148(2):246-260
The central role of multisubunit tethering complexes in intracellular trafficking has been established in yeast and mammalian systems. However, little is known about their roles in the stress responses and the early secretory pathway in Arabidopsis. In this study, Maigo2 (MAG2), which is equivalent to the yeast Tip20p and mammalian Rad50‐interacting protein, is found to be required for the responses to salt stress, osmotic stress and abscisic acid in seed germination and vegetative growth, and MAG2‐like (MAG2L) is partially redundant with MAG2 in response to environmental stresses. MAG2 strongly interacts with the central region of ZW10, and both proteins are important as plant endoplasmic reticulum (ER)‐stress regulators. ER morphology and vacuolar protein trafficking are unaffected in the mag2, mag2l and zw10 mutants, and the secretory marker to the apoplast is correctly transported in mag2 plants, which indicate that MAG2 functions as a complex with ZW10, and is potentially involved in Golgi‐to‐ER retrograde trafficking. Therefore, a new role for ER–Golgi membrane trafficking in abiotic‐stress and ER‐stress responses is discovered. 相似文献
987.
988.
D. P. Gladue V. O'Donnell R. Baker-Branstetter L. G. Holinka J. M. Pacheco I. Fernández Sainz Z. Lu X. Ambroggio L. Rodriguez M. V. Borca 《Journal of virology》2013,87(12):6794-6803
Foot-and-mouth disease virus (FMDV), the causative agent of foot-and-mouth disease, is an Aphthovirus within the Picornaviridae family. During infection with FMDV, several host cell membrane rearrangements occur to form sites of viral replication. FMDV protein 2C is part of the replication complex and thought to have multiple roles during virus replication. To better understand the role of 2C in the process of virus replication, we have been using a yeast two-hybrid approach to identify host proteins that interact with 2C. We recently reported that cellular Beclin1 is a natural ligand of 2C and that it is involved in the autophagy pathway, which was shown to be important for FMDV replication. Here, we report that cellular vimentin is also a specific host binding partner for 2C. The 2C-vimentin interaction was further confirmed by coimmunoprecipitation and immunofluorescence staining to occur in FMDV-infected cells. It was shown that upon infection a vimentin structure forms around 2C and that this structure is later resolved or disappears. Interestingly, overexpression of vimentin had no effect on virus replication; however, overexpression of a truncated dominant-negative form of vimentin resulted in a significant decrease in viral yield. Acrylamide, which causes disruption of vimentin filaments, also inhibited viral yield. Alanine scanning mutagenesis was used to map the specific amino acid residues in 2C critical for vimentin binding. Using reverse genetics, we identified 2C residues that are necessary for virus growth, suggesting that the interaction between FMDV 2C and cellular vimentin is essential for virus replication. 相似文献
989.
990.
An integrative gene expression system has been constructed for the directional assembly of biological components in Synechocystis PCC6803. We have characterized 11 promoter parts with various expression efficiencies for genetic engineering of Synechocystis for the production of fatty alcohols. This was achieved by integrating several genetic modifications including the expression of multiple-copies of fatty acyl-CoA reductase (FAR) under the control of strong promoters, disruption of the competing pathways for poly-β-hydroxybutyrate and glycogen synthesis, and for peptide truncation of the FAR. In shake-flask cultures, the production of fatty alcohols was significantly improved with a yield of 761 ± 216 μg/g cell dry weight in Synechocystis, which is the highest reported to date. 相似文献