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851.
Lei-Lei Chen Tie Bin Zhu Hang Yin Jun Huang Lian Sheng Wang Ke Jiang Cao Zhi Jian Yang 《Molecular biology reports》2010,37(7):3067-3072
Endothelial nitric oxide synthase (eNOS) and nitric oxide (NO) may play an important role in attenuating cardiac remodeling
and apoptosis after myocardial infarction. However, the anti-inflammation effects of eNOS in infarcted myocardium and the
role of MAPK signaling in eNOS/NO mediated cardiac remodeling have not yet been elucidated. Adenovirus carrying Human eNOS
gene was delivered locally into heart 4 days prior to induction of myocardial infarction (MI) by left anterior descending
coronary artery ligation. Monocyte/macrophage infiltration was detected by ED-1 immunohistochemistry. Western blot was employed
to examine the activation of MAPK. eNOS gene transfer significantly reduced myocardial infarct size and improved cardiac contractility
as well as left ventricle (LV) diastolic function at 7 days after MI. In addition, eNOS gene transfer decreased monocyte/macrophage
infiltration in the infarct region of the heart. Phosphorylation of MAPK after MI were also dramatically reduced by eNOS gene
transfer. All the protective effects of eNOS were blocked by N(ω)-nitro-l-arginine methyl ester (L-NAME) administration, indicating a NO-mediated event. These results demonstrate that the eNOS/NO
system provides cardiac protection after MI injury through inhibition of inflammation and suppression of MAPK signaling. 相似文献
852.
Vallisneria natans and Vallisneria spinulosa are two morphologically very similar and sympatrically dominant submerged macrophytes in lakes of the middle-lower reaches of the Yangtze River. Genetic variation was compared based on a total of 196 individuals from six V. natans populations and 201 individuals from seven V. spinulosa populations. Using eight ISSR primers, a total of 139 and 129 DNA fragments were generated with 121 being polymorphic in V. natans and 99 in V. spinulosa. The two species maintained higher genetic variation both at the species and population levels in comparison with other aquatic macrophytes. A higher level of genetic diversity among populations was found in V. natans than in V. spinulosa: the percentage of polymorphic loci (PPL) in V. natans was 52-62% vs. 38-47% in V. spinulosa; gene diversity (H) was 0.21 in V. natans vs. 0.17 in V. spinulosa.Both an analysis of molecular variance (AMOVA) and F-estimation (FST) showed that most of the total genetic variation resided within populations of both species (AMOVA: 85% and 80%; FST: 0.132 and 0.202), indicating low genetic differentiation between populations. Principal coordinates analysis (PCA) indicated evident gene flow between populations of both species. The outcrossing reproductive mode and pervasive gene flow might have played important roles in maintaining high genetic diversity and in shaping low population differentiation of the two Vallisneria species, while the extent of clonal growth might account for the different levels of population divergence between them. 相似文献
853.
Andrew W. Farrell Safina GadeockAleta Pupovac Bin WangIman Jalilian Marie RansonRonald Sluyter 《Biochimica et Biophysica Acta (BBA)/General Subjects》2010
Background
The extracellular ATP-gated cation channel, P2X7 receptor, has an emerging role in neoplasia, however progress in the field is limited by a lack of malignant cell lines expressing this receptor.Methods
Immunofluorescence labelling and a fixed-time ATP-induced ethidium+ uptake assay were used to screen a panel of human malignant cell lines for the presence of functional P2X7. The presence of P2X7 was confirmed by RT-PCR, immunoblotting and pharmacological approaches. ATP-induced cell death was measured by colourimetric tetrazolium-based and cytofluorometric assays. ATP-induced CD23 shedding was measured by immunofluorescence labelling and ELISA.Results
RPMI 8226 multiple myeloma cells expressed P2X7 mRNA and protein, as well as P2X1, P2X4 and P2X5 mRNA. ATP induced ethidium+ uptake into these cells with an EC50 of ~ 116 μM, and this uptake was reduced in the presence of extracellular Ca2+ and Mg2+. The P2X7 agonist 2'- and 3'-0(4-benzoylbenzoyl) ATP, but not UTP, induced ethidium+ uptake. ATP-induced ethidium+ uptake was impaired by the P2X7 antagonists, KN-62 and A-438079. ATP induced death and CD23 shedding in RPMI 8226 cells, and both processes were impaired by P2X7 antagonists. The metalloprotease antagonists, BB-94 and GM6001, impaired ATP-induced CD23 shedding but not ethidium+ uptake.Conclusions
P2X7 receptor activation induces cell death and CD23 shedding in RPMI 8226 cells.General significance
RPMI 8226 cells may be useful to study the role of P2X7 in multiple myeloma and B-lymphocytes. 相似文献854.
Gabriela E. Davey Bin Wu Yuancai Dong Uttam Surana Curt A. Davey 《Nucleic acids research》2010,38(6):2081-2088
DNA stretching in the nucleosome core can cause dramatic structural distortions, which may influence compaction and factor recognition in chromatin. We find that the base pair unstacking arising from stretching-induced extreme minor groove kinking near the nucleosome centre creates a hot spot for intercalation and alkylation by a novel anticancer compound. This may have far reaching implications for how chromatin structure can influence binding of intercalator species and indicates potential for the development of site selective DNA-binding agents that target unique conformational features of the nucleosome. 相似文献
855.
Jun-ling Hou Wei-dong Li Qiao-yun Zheng Wen-quan Wang Bin Xiao Dan Xing 《Biochemical Systematics and Ecology》2010
Effects of low light intensity on growth and accumulation of secondary metabolites of a medicinal plant Glycyrrhiza uralensis Fisch. were investigated. Hydroponic-cultivated one year-old rhizome seedlings were grown under three low irradiances, 200, 100, and 50 μmol m−2 s−1 for 135 days. Control plants were cultured under natural light conditions. Low light intensity stress decreased leaf thickness, photosynthesis and biomass, but increased leaf area and chlorophyll concentrations. Low light intensity also significantly increased accumulation of glycyrrhizic acid and liquiritin in the root, while the maximum values of both secondary metabolites were obtained under an irradiance of 100 μmol m−2 s−1. Concentrations of both secondary metabolites were negatively correlated with root biomass. The results suggested that G. uralensis could endure an environment with low light intensity and suitable light control might increase the secondary metabolite contents within agroforestry systems. 相似文献
856.
Bin He Xiaomeng Yu Moran Margolis Xianghua Liu Xiaohong Leng Yael Etzion Fei Zheng Nan Lu Florante A. Quiocho Dganit Danino Zheng Zhou 《Molecular biology of the cell》2010,21(4):610-629
Dynamins are large GTPases that oligomerize along membranes. Dynamin''s membrane fission activity is believed to underlie many of its physiological functions in membrane trafficking. Previously, we reported that DYN-1 (Caenorhabditis elegans dynamin) drove the engulfment and degradation of apoptotic cells through promoting the recruitment and fusion of intracellular vesicles to phagocytic cups and phagosomes, an activity distinct from dynamin''s well-known membrane fission activity. Here, we have detected the oligomerization of DYN-1 in living C. elegans embryos and identified DYN-1 mutations that abolish DYN-1''s oligomerization or GTPase activities. Specifically, abolishing self-assembly destroys DYN-1''s association with the surfaces of extending pseudopods and maturing phagosomes, whereas inactivating guanosine triphosphate (GTP) binding blocks the dissociation of DYN-1 from these membranes. Abolishing the self-assembly or GTPase activities of DYN-1 leads to common as well as differential phagosomal maturation defects. Whereas both types of mutations cause delays in the transient enrichment of the RAB-5 GTPase to phagosomal surfaces, only the self-assembly mutation but not GTP binding mutation causes failure in recruiting the RAB-7 GTPase to phagosomal surfaces. We propose that during cell corpse removal, dynamin''s self-assembly and GTP hydrolysis activities establish a precise dynamic control of DYN-1''s transient association to its target membranes and that this control mechanism underlies the dynamic recruitment of downstream effectors to target membranes. 相似文献
857.
Youwei Wang Zhibo Han Shulin Yan Aibin Mao Bin Wang He Ren Ying Chi Zhongchao Han 《In vitro cellular & developmental biology. Animal》2010,46(7):595-599
In real-time quantitative PCR, the accuracy of normalized data is highly dependent on the stability of the reference genes.
However, reference gene expression in a given cell type or experimental condition can vary considerably. The goal of this
study was to establish a reliable set of reference genes for real-time PCR studies using human umbilical cord mesenchymal
stem cells with long-term in vitro expansion. The stability of ten potential reference genes was examined in human umbilical
cord mesenchymal stem cells. We found that Ywhaz and Rpl13a, not beta-actin or Gapdh, were the most stably expressed of the internal control genes in different passages of human umbilical cord mesenchymal stem
cells. Ywhaz and Rpl13a could be used as reference genes for relative gene quantification and normalization purposes in real-time PCR studies of
human umbilical cord mesenchymal stem cells. 相似文献
858.
Xiuli Wang Xiangying Meng Bin Song Xuemei Qiu Haiying Liu 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2010,155(3):327-330
Myostatin (MSTN) is a member of the transforming growth factor-β superfamily which negatively regulates growth of muscle tissue. In this study, 103 cultivated Chlamys farreri individuals were screened for polymorphisms in the MSTN gene using PCR-single strand conformation polymorphism (PCR-SSCP) and DNA sequencing methods. Two mutations were found: A/G at position 327 in exon 2, which caused an amino acid change from Thr to Ala (Thr305Ala), and C/T at position 289 in exon 3, which caused an amino acid change from Cys to Arg (Cys422Arg). One way ANOVA of the SNPs and growth traits showed that genotype GG of primer M5 had significantly higher body mass, soft-tissue mass, adductor muscle mass, shell length, shell height, absolute growth rate of shell height and body mass than those of genotype AG and AA (P < 0.05). Genotype frequencies of genotype AA, AG and GG were 68.94%, 27.18% and 3.88%, respectively. The results present evidence that the C. farreri MSTN gene may be selected as a candidate gene for these growth traits. 相似文献
859.
860.