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991.
HuiPing Mao Fumiko Iwanaga Norikazu Yamanaka Fukuju Yamamoto 《Landscape and Ecological Engineering》2008,4(2):75-82
Growth, photosynthesis, and Na+, K+, and Ca2+ distributions were investigated in 2-year-old hydroponically cultured Populus alba L. cuttings exposed to salt stresses (0, 0.85, 8.5, 17, and 85 mM NaCl in experiment 1 and 0, 50, 100, 150, and 200 mM in
experiment 2) for 4 weeks in 2/5 Hoagland solution. Salt did not markedly inhibit height growth and diameter increment in
150 and 100 mM NaCl, respectively. The 85 mM NaCl treatment increased the dry weights of roots and total dry weight of plants,
while 150 mM NaCl significantly reduced the dry weights of leaves, stems, and total plant weight. The decline in the photosynthetic
rate lagged 2 weeks behind that of stomatal conductance in the 50 and 100 mM salt solutions. Different ions exhibited different
distributions in different parts of the plant. Most Na+ ions were excluded and/or compartmentalized in roots at low and moderate salt stress (≤50 mM). K+ content in leaves increased with the increase in the salt concentration in the growth solutions. 相似文献
992.
杏仁核点燃模型癫痫样放电传播途径研究 总被引:1,自引:0,他引:1
目的 :探讨杏仁核点燃模型癫痫样放电的传播途径。方法 :选择健康Wistar大鼠 3 0只以电刺激杏仁核的方式制作杏仁核点燃癫痫模型 ,于右侧杏仁核、左侧海马及右侧额叶皮质埋植电极记录脑电活动 ,观察电刺激杏仁核时在杏仁核、海马及额叶皮质出现癫痫样放电的潜伏期、最低刺激强度及癫痫样放电的持续时间。结果 :杏仁核出现癫痫样放电时 ,海马及皮质均未记录到癫痫样放电。而当杏仁核、海马及皮质三处出现癫痫样放电时的最低刺激强度依次增大 ,潜伏期依次延长 ,海马处癫痫样放电的持续时间最长。结论 :杏仁核点燃模型癫痫样放电可能由杏仁核经海马传至皮层 ,海马可能为癫痫样放电传播的重要结构 相似文献
993.
Siwei Liu Bingyu Zou Tian Tian Xiaohui Luo Banyun Mao Xun Zhang Huajiang Lei 《Journal of cellular biochemistry》2019,120(5):7581-7589
To determine how the lncRNA FER1L4 in ovarian cancer cells influences paclitaxel (PTX) resistance, we examined the expression level of FER1L4 in human ovarian epithelial cell lines IOSE80 and HOSEpiC and human ovarian cancer cell lines OVCAR-3, Caov-3, and SKOV3 through RNA isolation and quantitative polymerase chain reaction (qRT-PCR). SKOV3 cell lines were treated with PTX. The cell survival rate and apoptosis rate of SKOV3 and SKOV3-PR at different PTX dose levels were evaluated. Next, qRT-PCR was performed to detect the expression of FER1L4 in SKOV3 and SKOV3-PR cell lines. SKOV3-PR cell lines were transfected with pcDNA3.1 as the control group (SKOV3-PR/pcDNA3.1) or pcDNA3.1-FER1L4 to upregulate the expression level of FER1L4 (SKOV3-PR/pcDNA3.1-FER1L4). The level of cell survival, apoptosis, and colony formation were compared between the two groups using MTT, flow cytometry analysis, and colony formation assay. To reveal the molecular mechanism, we measured the relative protein phosphorylation level of ERK and MAPK in SKOV3, SKOV3-PR, SKOV3-PR/pcDNA3.1, and SKOV3-PR/pcDNA3.1-FER1L4 groups using an enzyme-linked immunosorbent assay. The effects of SB203580 (a p38 MAPK inhibitor) on PTX were also investigated to reveal the function of the MAPK pathway on the PTX tolerance of SKOV3. In comparison with normal ovarian epithelial cells, FER1L4 was downregulated. The FER1L4 level was decreased in human ovarian cancer cells with drug resistance than in common ovarian cancer cells. The upregulation of FER1L4 could promote the PTX sensitivity of ovarian cancer cells. The increased level of FER1L4 could suppress the PTX resistance of ovarian cancer cells through the inhibition of the MAPK signaling pathway. 相似文献
994.
Liu X Chen M Collins HL Onstad D Roush R Zhang Q Shelton AM 《Journal of economic entomology》2012,105(2):354-362
In the laboratory and in cages in the greenhouse, we evaluated the toxicity of two insecticides (lambda-cyhalothrin and spinosad) on the parasitoid, Diadegma insulare (Cresson), and the predator, Coleomegilla maculate (DeGeer), both natural enemies of the diamondback moth, Plutella xylostella (L.). Lambda-cyhalothrin was very toxic to both natural enemies. Spinosad was less toxic to C. maculata adults and larvae, and slightly toxic to D. insulare. Both natural enemies suppressed P. xylostella populations in cages with 80% spinosad-treated and 20% nontreated plants; such suppression was not seen when lambda-cyhalothrin was used. Using broccoli, Brassica oleracea L. variety italica, a common host for P. xylostella, we also studied direct and indirect effects of both natural enemies in the presence and absence of the two insecticides and to different P. xylostella genotypes: resistant to the insecticide, susceptible, or heterozygous. Neither natural enemy could distinguish host genotype if P. xylostella were feeding on nontreated plants. They could also not distinguish between larvae feeding on spinosad-treated plants and nontreated plants, but D. insulare could distinguish between larvae feeding on lambda-cyhalothrin treated and nontreated plants. Our studies suggest that lambda-cyhalothrin has direct toxicity to these two natural enemies, can affect their host foraging and acceptance of P. xylostella and consequently would not be compatible in conserving these natural enemies in a program for suppression of P. xylostella. In contrast, our studies suggest that treatment with spinosad has much less effect on these natural enemies and would allow them to help suppress populations of P. xylostella. These findings are discussed in relation to the evolution of insecticide resistance and suppression of the pest populations. 相似文献
995.
J. Mao Q. Liu X. Yang C. Long M. Zhao H. Zeng H. Liu J. Yuan D. Qiu 《The Annals of applied biology》2010,156(3):411-420
A new protein elicitor, PeaT1, was purified from the mycelium of Alternaria tenuissima by column chromatography. PeaT1 was identified as a heat-stable and acidic protein. It induced systemic acquired resistance to tobacco mosaic virus (TMV) in tobacco plants but did not cause hypersensitive response. The elicitor-encoding gene was cloned by rapid amplification of cDNA ends method. Sequence analysis revealed that the cDNA is 624 bp in length and the open reading frame encodes for a polypeptide of 207 amino acids with a nascent polypeptide-associated complex domain. The peaT1 gene was cloned into the expression vector pET-28a and transformed into Escherichia coli BL21 (DE3). The recombinant elicitor also triggered defence responses in intact tobacco plants. The availability of the pure protein offers the possibility to isolate the corresponding receptor and links it to the downstream signalling pathway. 相似文献
996.
Li Jiang Dongxu He Dantong Yang Zhen Chen Qiongxi Pan Aiqin Mao Yanfei Cai Xiyuan Li Hui Xing Mei Shi Yun Chen Iain C. Bruce Teng Wang Linfang Jin Xiaowei Qi Dong Hua Jian Jin Xin Ma 《FEBS letters》2014
To investigate the role of microRNAs in the development of chemoresistance and related epithelial–mesenchymal transition (EMT), we examined the effect of miR-489 in adriamycin (ADM)-resistant human breast cancer cells (MCF-7/ADM). MiR-489 was significantly suppressed in MCF-7/ADM cells compared with chemosensitive parental control MCF-7/WT cells. Forced-expression of miR-489 reversed chemoresistance. Furthermore, Smad3 was identified as the target of miR-489 and is highly expressed in MCF-7/ADM cells. Forced expression of miR-489 both inhibited Smad3 expression and Smad3 related EMT properties. Finally, the interactions between Smad3, miR-489 and EMT were confirmed in chemoresistant tumor xenografts and clinical samples, indicating their potential implication for treatment of chemoresistance. 相似文献
997.
Zhidan Zeng Qingfeng Zeng Nian Liu Artem R. Oganov Qiaoshi Zeng Yi Cui Wendy L. Mao 《Liver Transplantation》2015,5(12)
Li15Si4, the only crystalline phase that forms during lithiation of the Si anode in lithium‐ion batteries, is found to undergo a structural transition to a new phase at 7 GPa. Despite the large unit cell of Li15Si4 (152 atoms in the unit cell), ab initio evolutionary metadynamics (using the USPEX code) successfully predicts the atomic structure of this new phase (β‐Li15Si4), which has an orthorhombic structure with an Fdd2 space group. In the new β‐Li15Si4 phase Si atoms are isolated by Li atoms analogous to the original cubic phase (α‐Li15Si4), whereas the atomic packing is more efficient owing to the higher Si? Li coordination number and shorter Si? Li, Li? Li bonds. β‐Li15Si4 has substantially larger elastic moduli compared with α‐Li15Si4, and has a good electrical conductivity. As a result, β‐Li15Si4 has superior resistance to deformation and fracture under stress. The theoretical volume expansion of Si would decrease 25% if it transforms to β‐Li15Si4, instead of α‐Li15Si4, during lithiation. Moreover, β‐Li15Si4 can be recovered back to ambient pressure, providing opportunities to further investigate its properties and potential applications. 相似文献
998.
Skavdahl M Steenbergen C Clark J Myers P Demianenko T Mao L Rockman HA Korach KS Murphy E 《American journal of physiology. Heart and circulatory physiology》2005,288(2):H469-H476
The goal of this study was to determine the role of estrogen receptor subtypes in the development of pressure overload hypertrophy in mice. Epidemiological studies have suggested gender differences in the development of hypertrophy and heart disease, but the mechanism and the role of estrogen receptor subtypes are not established. We performed transverse aortic constriction (TAC) and sham operations in male and female wild-type (WT) mice and mice lacking functional estrogen receptor-alpha [alpha-estrogen receptor knockout (alpha-ERKO)] and mice lacking estrogen receptor-beta (beta-ERKO). Body, heart, and lung weights were measured 2 wk postsurgery. WT male mice subjected to TAC showed a 64% increase in the heart weight-to-body weight ratio (HW/BW) compared with sham, and WT males have increased lung weight at 2 wk. WT female mice subjected to TAC showed a 31% increase in HW/BW compared with sham, which was significantly less than their male counterparts and with no evidence of heart failure. alpha-ERKO females developed HW/BW nearly identical to that seen in WT littermate females in response to TAC, indicating that estrogen receptor-alpha is not essential for the attenuation of hypertrophy observed in WT females. In contrast, beta-ERKO females responded to TAC with a significantly greater increase in HW/BW than WT littermate females. beta-ERKO females have lower expression of lipoprotein lipase at baseline than WT or alpha-ERKO females. These data suggest an important role for estrogen receptor-beta in attenuating the hypertrophic response to pressure overload in females. 相似文献
999.
1000.
Paumet F Le Mao J Martin S Galli T David B Blank U Roa M 《Journal of immunology (Baltimore, Md. : 1950)》2000,164(11):5850-5857
Mast cells upon stimulation through high affinity IgE receptors massively release inflammatory mediators by the fusion of specialized secretory granules (related to lysosomes) with the plasma membrane. Using the RBL-2H3 rat mast cell line, we investigated whether granule secretion involves components of the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) machinery. Several isoforms of each family of SNARE proteins were expressed. Among those, synaptosome-associated protein of 23 kDa (SNAP23) was central in SNARE complex formation. Within the syntaxin family, syntaxin 4 interacted with SNAP23 and all vesicle-associated membrane proteins (VAMPs) examined, except tetanus neurotoxin insensitive VAMP (TI-VAMP). Overexpression of syntaxin 4, but not of syntaxin 2 nor syntaxin 3, caused inhibition of FcepsilonRI-dependent exocytosis. Four VAMP proteins, i.e., VAMP2, cellubrevin, TI-VAMP, and VAMP8, were present on intracellular membrane structures, with VAMP8 residing mainly on mediator-containing secretory granules. We suggest that syntaxin 4, SNAP23, and VAMP8 may be involved in regulation of mast cell exocytosis. Furthermore, these results are the first demonstration that the nonneuronal VAMP8 isoform, originally localized on early endosomes, is present in a regulated secretory compartment. 相似文献