排序方式: 共有65条查询结果,搜索用时 31 毫秒
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Tóth-Zsámboki E Horváth E Vargova K Pankotai E Murthy K Zsengellér Z Bárány T Pék T Fekete K Kiss RG Préda I Lacza Z Gerö D Szabó C 《Molecular medicine (Cambridge, Mass.)》2006,12(9-10):221-228
Reactive free radical and oxidant production leads to DNA damage during myocardial ischemia/reperfusion. Consequent overactivation of poly(ADP-ribose) polymerase (PARP) promotes cellular energy deficit and necrosis. We hypothesized that PARP is activated in circulating leukocytes in patients with myocardial infarction and reperfusion during primary percutaneous coronary intervention (PCI). In 15 patients with ST segment elevation acute myocardial infarction, before and after primary PCI and 24 and 96 h later, we determined serum hydrogen peroxide concentrations, plasma levels of the oxidative DNA adduct 8-hydroxy-2'-deoxyguanosine (8OHdG), tyrosine nitration, PARP activation, and translocation of apoptosis-inducing factor (AIF) in circulating leukocytes. Plasma 8OHdG levels and leukocyte tyrosine nitration were rapidly increased by PCI. Similarly, poly(ADP-ribose) content of the leukocytes increased in cells isolated just after PCI, indicating immediate PARP activation triggered by reperfusion of the myocardium. In contrast, serum hydrogen peroxide concentrations and the translocation of AIF gradually increased over time and were most pronounced at 96 h. Reperfusion-related oxidative/nitrosative stress triggers DNA damage, which leads to PARP activation in circulating leukocytes. Translocation of AIF and lipid peroxidation occurs at a later stage. These results represent the first direct demonstration of PARP activation in human myocardial infarction. Future work is required to test whether pharmacological inhibition of PARP may offer myocardial protection during primary PCI. 相似文献
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Attila Cselenyák Eszter Pankotai Eszter M Horváth Levente Kiss Zsombor Lacza 《BMC cell biology》2010,11(1):29
Background
Bone marrow derived mesenchymal stem cells (MSCs) are promising candidates for cell based therapies in myocardial infarction. However, the exact underlying cellular mechanisms are still not fully understood. Our aim was to explore the possible role of direct cell-to-cell interaction between ischemic H9c2 cardiomyoblasts and normal MSCs. Using an in vitro ischemia model of 150 minutes of oxygen glucose deprivation we investigated cell viability and cell interactions with confocal microscopy and flow cytometry. 相似文献44.
Isolation of two populations of sperm cells and microelectrophoresis of pairs of sperm cells from pollen tubes of tobacco (Nicotiana tabacum) 总被引:1,自引:1,他引:0
Prior research has indicated that the two sperm cells of Nicotiana tabacum are dimorphic, suggesting that they may participate in preferential fertilization during in vivo fusion with the egg and
central cells. To probe the mechanism of potential preferential fertilization in this plant, it will be necessary to use modern
sensitive molecular techniques. For this purpose, two individual populations of two sperm cells, constituting the Svn (associated
with the vegetative nucleus) and Sua (unassociated with the vegetative nucleus), were isolated in the thousands from tobacco
pollen tubes with a micromanipulator as a preliminary step toward research on gametic recognition using molecular techniques.
Microelectrophoresis of paired sperm cells from a single pollen tube was conducted at different developmental stages. Sperm
cells isolated from 1-, 2-, 3- and 4-cm stylar lengths migrated to the negative pole, with the Sua displaying significantly
greater electrophoretic mobility than the Svn, reflecting a more positively charged cell surface on the Sua. The sperm cells
isolated from 1-cm style are very sensitive to electron potential in an electrophoretic field, presumably reflecting that
they are still in a young state. Differences in cell surface charge between the Sua and Svn may be related with cell fate
during fertilization.
Supported by National Natural Science Foundation of CHINA (30170060) 相似文献
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Ciccone NA Lacza CT Hou MY Gregory SJ Kam KY Xu S Kaiser UB 《Molecular endocrinology (Baltimore, Md.)》2008,22(8):1908-1923
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S Senthilvel B Jayashree V Mahalakshmi P Sathish Kumar S Nakka T Nepolean CT Hash 《BMC plant biology》2008,8(1):119
Background
Pearl millet [Pennisetum glaucum (L.) R. Br.] is a staple food and fodder crop of marginal agricultural lands of sub-Saharan Africa and the Indian subcontinent. It is also a summer forage crop in the southern USA, Australia and Latin America, and is the preferred mulch in Brazilian no-till soybean production systems. Use of molecular marker technology for pearl millet genetic improvement has been limited. Progress is hampered by insufficient numbers of PCR-compatible co-dominant markers that can be used readily in applied breeding programmes. Therefore, we sought to develop additional SSR markers for the pearl millet research community. 相似文献47.
Reverte CG Yuan L Keady BT Lacza C Attfield KR Mahon GM Freeman B Whitehead IP Hake LE 《Developmental biology》2003,255(2):383-398
XGef was isolated in a screen for proteins interacting with CPEB, a regulator of mRNA translation in early Xenopus development. XGef is a Rho-family guanine nucleotide exchange factor and activates Cdc42 in mammalian cells. Endogenous XGef (58 kDa) interacts with recombinant CPEB, and recombinant XGef interacts with endogenous CPEB in Xenopus oocytes. Injection of XGef antibodies into stage VI Xenopus oocytes blocks progesterone-induced oocyte maturation and prevents the polyadenylation and translation of c-mos mRNA; injection of XGef rescues these events. Overexpression of XGef in oocytes accelerates progesterone-induced oocyte maturation and the polyadenylation and translation of c-mos mRNA. Overexpression of a nucleotide exchange deficient version of XGef, which retains the ability to interact with CPEB, no longer accelerates oocyte maturation or Mos synthesis, suggesting that XGef exchange factor activity is required for the influence of overexpressed XGef on oocyte maturation. XGef overexpression continues to accelerate c-mos polyadenylation in the absence of Mos protein, but does not stimulate MAPK phosphorylation, MPF activation, or oocyte maturation, indicating that XGef may function through the Mos pathway to influence oocyte maturation. These results suggest that XGef may be an early acting component of the progesterone-induced oocyte maturation pathway. 相似文献
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The IgG1hybridoma antibody, 91.9H, was originally raised against sulfated
mucins isolated from normal human colonic mucosa. Previous studies have
shown that the 91.9H antigen is expressed on normal colonic epithelial
cells and the sulfomucins that they produce, but not in the normal small
intestine and stomach. Tissue-specific changes occur in 91.9H antigen
expression in disease: the antigen diminishes in colonic carcinomas,
whereas in regions of gastric mucosa showing intestinal metaplasia and in
gastric carcinomas, the antigen is expressed as a "neo-antigen." This
report is concerned with elucidation, by the neoglycolipid technology, of
the determinant recognized by antibody 91.9H using sulfated and sialyl
oligosaccharides of Lewisa(Lea) and Lextypes, and analogs that lack
sulfate, sialic acid, or fucose. Binding experiments with the lipid-linked
oligosaccharides immobilized on chromatograms or on microwells, and
inhibition of binding experiments with free oligosaccharides based on di-,
tri- and tetrasaccharide backbones, show that the 91.9H antigenic
determinant is based on a trisaccharide backbone, and consists of the
3'-sulfated Leatetrasaccharide sequence, which is a potent ligand for the
E- and L-selectins. The antibody gives a relatively low signal with the
3'-sulfated non-fucosylated backbone, and has no detectable cross- reaction
with the 3'-sulfated Lexisomer, nor with sialyl-Leaand - Lexanalogues.
Antibody 91.9H is a valuable addition, therefore, to the repertoire of
reagents for mapping details of the distribution, and determining the
relative importance of sulfated and sialyl oligosaccharides as ligands for
the selectins, in normal and pathological epithelia and endothelia.
相似文献