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This study was performed to analyze the expression of four and a half LIM domains 1 (FHL1) in gastric carcinoma tissue and its correlation with the clinicopathological characteristics of gastric cancer. In addition, the role of FHL1 in the invasion and metastasis of gastric cancer cells was investigated to provide an experimental basis for future treatments of gastric cancer. FHL1 mRNA and protein expression in gastric carcinoma and the adjacent normal gastric mucosa tissue were determined using RT-PCR and western blots. Correlations of FHL1 expression with the incidence, progression, and clinicopathological characteristics of gastric cancer were analyzed. Changes in the invasion and metastatic potential of MKN45 human gastric cancer cells were observed after the transient transfection with an eukaryotic expression vector containing full-length FHL1. Expression of FHL1 mRNA in gastric carcinoma tissue was significantly lower than that in the adjacent normal tissue (P < 0.05). FHL1 expression in gastric carcinoma tissue from patients who were positive for lymph node metastasis was significantly lower than those in patients who were negative for lymph node metastasis (P < 0.05). Lower FHL1 expression was correlated with lower degrees of differentiation, higher TNM stages, and greater invasive potential of the gastric cancer (P < 0.05). The FHL1 mRNA and protein expression patterns were similar in gastric cancer. FHL1 protein expression in gastric carcinoma tissue was significantly lower than that in the surrounding normal tissue (P < 0.05). FHL1 protein expression was significantly lower in gastric carcinoma tissue from patients who were positive for lymph node metastasis than that detected in patients with no lymph node metastasis (P < 0.05). Lower FHL1 protein expression was correlated with lower degrees of differentiation, higher TNM stages, and greater invasive potential in gastric cancer (P < 0.05). However, the expression of FHL1 was independent of the patient's gender, age, and tumor size (P > 0.05). Overexpression of FHL1 in the MKN45 human gastric cancer cell line using an eukaryotic expression vector resulted in a significant reduction in the invasiveness and metastatic ability of these cells as determined using the Transwell chamber invasion assay (P < 0.05). The decrease in or loss of FHL1 expression may be related to the incidence, progression, invasiveness, and metastatic potential of gastric cancer.  相似文献   
43.
目的总结分析心内直视手术中七十岁以上患者的体外循环特点和管理方法。方法 2005年3月至2008年7月间7000余例手术中70岁以上患者共有194例,分类进行心内直视手术。体外循环时全部应用进口膜肺,勃脉力A和胶体预充,常规加入白蛋白、激素和乌司他丁;心肌保护采用间断灌注4:1冷含血停搏液,顺灌逆灌和桥灌相结合;常规监测混合静脉氧饱和度和血细胞压积,积极应用超滤技术。结果术中转流平稳,血流动力学稳定,监测指标均在正常范围,平均体外循环时间和主动脉阻断时间分别为111.5±40.4m in和63.6±21.0m in,自动复跳率52.6%,平均搭桥数目3.4±0.8支,术后平均气管拔管时间24.0±12.7h,平均ICU时间4.7±3.5d。结论 70岁以上患者以瓣膜和冠状动脉病变为主、病变复杂,体外循环时间和主动脉阻断时间较长,各脏器保护要求高,针对高龄患者的特点,制定相应的体外循环管理方法,是保证手术成功的重要因素。  相似文献   
44.
Yao K  Wang J  Zhang W  Lee JS  Wang C  Chu F  He X  Tang C 《Biomacromolecules》2011,12(6):2171-2177
We have carried out the synthesis of side-chain rosin-ester-structured poly(ε-caprolactone) (PCL) through a combination of ring-opening polymerization and click chemistry. Rosin structures are shown to be effectively incorporated into each repeat unit of caprolactone. This simple and versatile methodology does not require sophisticated purification of raw renewable biomass from nature. The rosin properties have been successfully imparted to the PCL polymers. The bulky hydrophenanthrene group of rosin increases the glass-transition temperature of PCL by >100 °C, whereas the hydrocarbon nature of rosin structures provides PCL excellent hydrophobicity with contact angle very similar to polystyrene and very low water uptake. The rosin-containing PCL graft copolymers exhibit full degradability and good biocompatibility. This study illustrates a general strategy to prepare a new class of renewable hydrocarbon-rich degradable biopolymers.  相似文献   
45.
Che L  Tang D  Wang K  Wang M  Zhu K  Yu H  Gu M  Cheng Z 《Cell research》2011,21(4):654-665
The events occurring at the onset of meiosis have not been fully elucidated. In the present study, OsAM1 was identified in rice (Oryza sativa L.) by map-based cloning. OsAM1, a homolog of Arabidopsis SWI1 and maize AM1, encodes a protein with a coiled-coil domain in its central region. In the Osam1 mutant, pollen mother cells are arrested at leptotene, showing that OsAM1 is required for the leptotene-zygotene transition. Immunocytological analysis revealed that OsAM1 exists as foci in early prophase I meiocytes. Very faint OsREC8 foci persisted in the Osam1 mutant, indicating that OsAM1 is not required for the initial meiotic recruitment of OsREC8. In the absence of OsAM1, many other critical meiotic components, including PAIR2, ZEP1 and OsMER3, could not be correctly installed onto chromosomes. In contrast, in pair2, Osmer3 and zep1 mutants, OsAM1 could be loaded normally, suggesting that OsAM1 plays a fundamental role in building the proper chromosome structure at the beginning of meiosis.  相似文献   
46.
The change of atom configuration in GaAs, caused by intrinsic point defects (Ga and As vacancies, Ga and As antisites, Ga and As interstitials), is first calculated by a plane wave pseudo-potential method with the generalised gradient approximation in the frame of density functional theory, and the most stable structure is obtained. Then, the formation energy of each kind of the native defect is calculated, by which the possibilities of the six kinds of point defects to be formed during crystal growth are analysed. The defect energy levels corresponding to each kind of the native point defect and their electron occupancy are analysed from the aspect of density of states. Finally, the elastic constants of GaAs saturable absorbers with native point defects are calculated, and the impacts on the elastic properties brought by native point defects are studied. The values of defect energy levels obtained will be helpful in ascertaining the mechanism of the EL2 deep level in the GaAs saturable absorber, and the analysis of the elastic properties of a GaAs crystal with native point defects will be helpful in guiding the application of the GaAs crystal as a saturable absorber in passively Q-switched lasers.  相似文献   
47.
正The same figure was misused for the PCR/RE assay results of Gn1a and GW2 fragments in Figure 3, and the arrows in the graphicsal result of GW2 were not on the tape. The corrected Figure 3 is as follows.  相似文献   
48.
49.
K Wang  M Wang  D Tang  Y Shen  C Miao  Q Hu  T Lu  Z Cheng 《PLoS genetics》2012,8(7):e1002809
HEI10 was first described in human as a RING domain-containing protein that regulates cell cycle and cell invasion. Mice HEI10(mei4) mutant displays no obvious defect other than meiotic failure from an absence of chiasmata. In this study, we characterize rice HEI10 by map-based cloning and explore its function during meiotic recombination. In the rice hei10 mutant, chiasma frequency is markedly reduced, and those remaining chiasmata exhibit a random distribution among cells, suggesting possible involvement of HEI10 in the formation of interference-sensitive crossovers (COs). However, mutation of HEI10 does not affect early recombination events and synaptonemal complex (SC) formation. HEI10 protein displays a highly dynamic localization on the meiotic chromosomes. It initially appears as distinct foci and co-localizes with MER3. Thereafter, HEI10 signals elongate along the chromosomes and finally restrict to prominent foci that specially localize to chiasma sites. The linear HEI10 signals always localize on ZEP1 signals, indicating that HEI10 extends along the chromosome in the wake of synapsis. Together our results suggest that HEI10 is the homolog of budding yeast Zip3 and Caenorhabditis elegans ZHP-3, and may specifically promote class I CO formation through modification of various meiotic components.  相似文献   
50.
We investigated the response of Mn-hyperaccumulator Phytolacca americana L. to manganese excess as well as the relationships between lignin deposition in the plant’s leaves, peroxidase and laccase activities in the leaf apoplast, and Mn toxicity. The exceptionally high tolerance of P. americana to Mn, both in solution and in tissue, was confirmed. No visible brown spot was observed in the leaves of plants treated with ≤10,000 μM Mn for 10 days. Mn treatment significantly increased lignin content and laccase activity in the apoplastic washing fluid (AWF) of P. americana leaves. In contrast, an increase in the Mn supply was paralleled by a significant decrease in the concentration of total phenolic compounds (TPCs) and in water-soluble guaiacol peroxidase (SPOD) activity in leaf AWF. This result suggested that an increase in lignin deposition decreased the concentration of apoplastic TPCs that are available to generate potentially toxic intermediates by acting as peroxidase substrates. Thus, data of the present study indicate that lignin formation by laccase activities reduces Mn toxicity and increases Mn tolerance of P. americana by depressing SPOD-mediated formation of toxic intermediates from TPCs.  相似文献   
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