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91.
Jiayi Tong Jiandong Ding Xiangbo Shen Long Chen Yeping Bian Genshan Ma Yuyu Yao Fang Yang 《PloS one》2013,8(11)
Objective
This study evaluated the effects of ultrasound combined with the homemade nitric oxide (NO) micro-bubble destruction on the in vitro proliferation, apoptosis, and migration of mesenchymal stem cells (MSCs). Furthermore, we studied whether or not irradiation of the NO micro-bubble combined with bone-marrow derived MSC infusion had a better effect on treating myocardial infarction. The possible mechanism of MSC delivery into the infarcted myocardium was also investigated.Methods
The murine bone marrow-derived MSCs were isolated, cultured, irradiated, and combined with different concentrations of NO microbubbles. MTT proliferation assay, annexin V-FITC apoptosis detection, migration assay, and RT-PCR were performed 24 h after the irradiation. The NO micro-bubbles was a intravenously injected, followed by the infusion of MSCs, which were labeled by CM-Dil. Myocardium was harvested 48 h later and the distribution of MSCs was observed by laser scanning confocal microscope after frozen sectioning. Echocardiography, histological examination, RT-PCR, and western blotting were performed four weeks after the cell transplantation.Results
Ultrasound combined with 1:70 NO micro-bubbles had no significant impact on the proliferation or apoptosis of MSCs. Transwell chamber findings demonstrated that MSCs migrated more efficiently in group that underwent ultrasound combined with 1:70 NO micro-bubbles. The Real-time PCR results indicated that the expression of CXCR4 was much higher in the group undergoing ultrasound combined with 1:70 NO micro-bubbles. The normalized fluorescence intensity greatly increased in the group of US+NO micro-bubbles and the cardiac function was also markedly improved. Immunohistochemical staining showed that the capillary density was much greater in the group of US+NO micro-bubbles as compared to that of the other groups. RT-PCR and western blotting also revealed a higher SDF-1 and VEGF expression in the group of US+NO micro-bubbles.Conclusions
NO micro-bubbles could be used in the cell transplantation, which efficiently promoted the MSC homing into the infarcted myocardium. 相似文献92.
Xing Wu Qunying Mao Xin Yao Pan Chen Xiangmei Chen Jie Shao Fan Gao Xiang Yu Fengcai Zhu Rongcheng Li Wenhui Li Zhenglun Liang Junzhi Wang Fengmin Lu 《PloS one》2013,8(6)
The level of neutralizing antibodies (NtAb) induced by vaccine inoculation is an important endpoint to evaluate the efficacy of EV71 vaccine. In order to evaluate the efficacy of EV71 vaccine, here, we reported the development of a novel pseudovirus system expression firefly luciferase (PVLA) for the quantitative measurement of NtAb. We first evaluated and validated the sensitivity and specificity of the PVLA method. A total of 326 serum samples from an epidemiological survey and 144 serum specimens from 3 clinical trials of EV71 vaccines were used, and the level of each specimen''s neutralizing antibodies (NtAb) was measured in parallel using both the conventional CPE-based and PVLA-based assay. Against the standard neutralization assay based on the inhibition of the cytopathic effect (CPE), the sensitivity and specificity of the PVLA method are 98% and 96%, respectively. Then, we tested the potential interference of NtAb against hepatitis A virus, Polio-I, Polio-II, and Polio-III standard antisera (WHO) and goat anti-G10/CA16 serum, the PVLA based assay showed no cross-reactivity with NtAb against other specific sera. Importantly, unlike CPE based method, no live replication-competent EV71 is used during the measurement. Taken together, PVLA is a rapid and specific assay with higher sensitivity and accuracy. It could serve as a valuable tool in assessing the efficacy of EV71 vaccines in clinical trials and disease surveillance in epidemiology studies. 相似文献
93.
94.
Baitian Xu Hongyin Zhang Keping Chen Qin Xu Yao Yao Hui Gao 《Current microbiology》2013,67(2):255-261
A new yeast antagonist, Pichia caribbica, isolated in our laboratory from the soil collected from unsprayed orchards, was evaluated for its biocontrol capability against Rhizopus stolonifer on peaches and the possible mechanisms involved. The decay incidence and lesion diameter of Rhizopus decay of peaches treated by P. caribbica were significantly reduced compared with the control fruits, and the higher the concentration of P. caribbica, the better the efficacy of the biocontrol. Rapid colonization of the yeast in peach wounds stored at 25 °C was observed. In peaches, the activities of peroxidase (POD), catalase (CAT), and phenylalanine ammonia-lyase (PAL) were significantly induced by P. caribbica treatment compared to those of the control fruits. All these results indicated that P. caribbica has a great potential for the development of commercial formulations to control postharvest Rhizopus decay of peaches. Its modes of action were based on competition for space and nutrients with pathogens, inducement of activities of defense-related enzymes such as POD, CAT, and PAL of peaches. 相似文献
95.
Lin Xu Qi Liu Min Qing Xin-Shen Yao Zhen-Ke Wen 《Biochemical and biophysical research communications》2009,382(3):571-824
Accumulating data suggested that CXCR4/SDF-1 pathway may play an important role in the metastasis of tumor. We previously demonstrated that CpG ODN could enhance the metastasis of human lung cancer cell via TLR9. Here we further evaluated the possible role of CXCR4/SDF-1 pathway in the enhanced metastasis of human lung cancer 95D cells induced by CpG ODN. Our data showed down-regulation of CXCR4 expression using siRNA against CXCR4 could significantly reduce the enhanced metastasis of 95D cells induced by CpG ODN both in vitro and in vivo. These results suggested that TLR9 agonist might promote the metastasis of human lung cancer cells via CXCR4/SDF-1 pathway. 相似文献
96.
97.
Calcium binding lysozyme from pigeon egg-white was crystallized by the hanging drop vapor diffusion technique using ammonium sulphate as a precipitant. The crystals belong to the orthorhombic system, space group P2(1)2(1)2(1), and have unit cell dimensions of a = 34.2 A, b = 34.8 A, and c = 99.4 A. One asymmetric unit contains one molecule of the pigeon lysozyme. The crystals diffract X-rays at least to 2.0 A resolution and are suitable for high resolution structure analysis. The diffraction data up to 3.0 A resolution were collected with a diffraction image processor, DIP100, using a Fuji imaging plate as an area detector. The structure was solved by the molecular replacement technique and refined to an R factor of 0.216. Least-squares fitting of the main-chains of pigeon egg-white lysozyme with those of chicken egg-white lysozyme and baboon alpha-lactalbumin showed that the main-chain folding of pigeon lysozyme is more similar to that of chicken lysozyme than that of alpha-lactalbumin. The largest differences between the pigeon and chicken lysozymes are in the surface loop regions. 相似文献
98.
Axotomy within 500 μm of the soma (close axotomy) causes identified neurons (anterior bulbar cells or ABCs) in the lamprey hindbrain to lose their normal polarity and regenerate axons ectopically from dendritic tips, while axotomy at more distal sites (distant axotomy) results in orthotopic axonal regeneration from the axon stump. We performed immunocytochemical, electron microscopic and in situ hybridization analyses comparing ABCs subjected to close and distant axotomy to elucidate the mechanism by which neuronal polarity is lost. We show that polarity loss in ABCs is selectively and invariably preceded and accompained by the following cellular changes: (1) a loss of many dendritic microtubules and their replacement with neurofilaments, (2) a loss of immunostaining for acetylated tubulin in the soma and proximal dendrites, and (3) an increase of immunostaining for phosphorylated neurofilaments in the distal dendrites. We also show that these changes do not depend on either the upregulation or spatial redistribution of neurofilament message, and thus must involve changes in the routing of neurofilament protein within axotomized ABCs. We conclude that close axotomy causes dendrites to undergo axonlike changes in the mechanisms that govern the somatofugal transport of neurofilament protein, and suggest that these changes require the reorganization of dendritic microtubules. We also suggest that the bulbous morphology and lack of f-actin in the tips of all regenerating sprouts supports the possibility that axonal regeneration in the lamprey CNS does not involve actin-mediated "pulling" of growth cones, but depends instead on the generation of internal extrusive forces. 相似文献
99.
Inherited human Caspase 10 mutations underlie defective lymphocyte and dendritic cell apoptosis in autoimmune lymphoproliferative syndrome type II. 总被引:32,自引:0,他引:32
J Wang L Zheng A Lobito F K Chan J Dale M Sneller X Yao J M Puck S E Straus M J Lenardo 《Cell》1999,98(1):47-58
Caspases are cysteine proteases that mediate programmed cell death in phylogenetically diverse multicellular organisms. We report here two kindreds with autoimmune lymphoproliferative syndrome (ALPS) type II, characterized by abnormal lymphocyte and dendritic cell homeostasis and immune regulatory defects, that harbor independent missense mutations in Caspase 10. These encode amino acid substitutions that decrease caspase activity and interfere with death receptor-induced apoptosis, particularly that stimulated by Fas ligand and TRAIL. These results provide evidence that inherited nonlethal caspase abnormalities cause pleiotropic apoptosis defects underlying autoimmunity in ALPS type II. 相似文献
100.
Xie H Patching SG Gallagher MP Litherland GJ Brough AR Venter H Yao SY Ng AM Young JD Herbert RB Henderson PJ Baldwin SA 《Molecular membrane biology》2004,21(5):323-336
NupG from Escherichia coli is the archetype of a family of nucleoside transporters found in several eubacterial groups and has distant homologues in eukaryotes, including man. To facilitate investigation of its molecular mechanism, we developed methods for expressing an oligohistidine-tagged form of NupG both at high levels (>20% of the inner membrane protein) in E. coli and in Xenopus laevis oocytes. In E. coli recombinant NupG transported purine (adenosine) and pyrimidine (uridine) nucleosides with apparent K(m) values of approximately 20-30 microM and transport was energized primarily by the membrane potential component of the proton motive force. Competition experiments in E. coli and measurements of uptake in oocytes confirmed that NupG was a broad-specificity transporter of purine and pyrimidine nucleosides. Importantly, using high-level expression in E. coli and magic-angle spinning cross-polarization solid-state nuclear magnetic resonance, we have for the first time been able directly to measure the binding of the permeant ([1'-(13)C]uridine) to the protein and to assess its relative mobility within the binding site, under non-energized conditions. Purification of over-expressed NupG to near homogeneity by metal chelate affinity chromatography, with retention of transport function in reconstitution assays, was also achieved. Fourier transform infrared and circular dichroism spectroscopy provided further evidence that the purified protein retained its 3D conformation and was predominantly alpha-helical in nature, consistent with a proposed structure containing 12 transmembrane helices. These findings open the way to elucidating the molecular mechanism of transport in this key family of membrane transporters. 相似文献