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41.
Păunescu V Deak E Herman D Siska IR Tănasie G Bunu C Anghel S Tatu CA Oprea TI Henschler R Rüster B Bistrian R Seifried E 《Journal of cellular and molecular medicine》2007,11(3):502-508
Our study examined whether human bone marrow-derived MSCs are able to differentiate, in vitro, into functional epithelial-like cells. MSCs were isolated from the sternum of 8 patients with different hematological disorders. The surface phenotype of these cells was characterized.To induce epithelial differentiation, MSCs were cultured using Epidermal Growth Factor, Keratinocyte Growth Factor, Hepatocyte Growth Factor and Insulin-like growth Factor-II. Differentiated cells were further characterized both morphologically and functionally by their capacity to express markers with specificity for epithelial lineage. The expression of cytokeratin 19 was assessed by immunocytochemistry, and cytokeratin 18 was evaluated by quantitative RT-PCR (Taq-man). The data demonstrate that human MSCs isolated from human bone marrow can differentiate into epithelial-like cells and may thus serve as a cell source for tissue engineering and cell therapy of epithelial tissue. 相似文献
42.
Structural organization and a standardized nomenclature for plant endo-1,4-beta-glucanases (cellulases) of glycosyl hydrolase family 9 下载免费PDF全文
43.
44.
Vergely C Maupoil V Clermont G Bril A Rochette L 《Archives of biochemistry and biophysics》2003,420(2):209-216
There is general agreement that free radicals are involved in reperfusion injury. Electron paramagnetic resonance (EPR) spectroscopy can be considered as the more suitable technique to directly measure and characterize free radical generation during myocardial ischemia and reperfusion. There are essentially two approaches used in the detection of unstable reactive species: freezing technique and spin traps. The detection of secondary free radicals or ascorbyl free radicals during reperfusion might provide an index of oxidative stress. Spin trapping can also characterize nitric oxide. EPR spectroscopy can provide important data regarding redox state and free radical metabolism but ideally, the spin traps must not interfere with cell or organism function. 相似文献
45.
Vertebrate female reproduction is limited by the oocyte stockpiles acquired during embryonic development. These are gradually depleted over the organism's lifetime through the process of apoptosis. The timer that triggers this cell death is yet to be identified. We used the Xenopus egg/oocyte system to examine the hypothesis that nutrient stores can regulate oocyte viability. We show that pentose-phosphate-pathway generation of NADPH is critical for oocyte survival and that the target of this regulation is caspase-2, previously shown to be required for oocyte death in mice. Pentose-phosphate-pathway-mediated inhibition of cell death was due to the inhibitory phosphorylation of caspase-2 by calcium/calmodulin-dependent protein kinase II (CaMKII). These data suggest that exhaustion of oocyte nutrients, resulting in an inability to generate NADPH, may contribute to ooctye apoptosis. These data also provide unexpected links between oocyte metabolism, CaMKII, and caspase-2. 相似文献
46.
Leulliot N Vicentini G Jordens J Quevillon-Cheruel S Schiltz M Barford D van Tilbeurgh H Goris J 《Molecular cell》2006,23(3):413-424
PTPA, an essential and specific activator of protein phosphatase 2A (PP2A), functions as a peptidyl prolyl isomerase (PPIase). We present here the crystal structures of human PTPA and of the two yeast orthologs (Ypa1 and Ypa2), revealing an all alpha-helical protein fold that is radically different from other PPIases. The protein is organized into two domains separated by a groove lined by highly conserved residues. To understand the molecular mechanism of PTPA activity, Ypa1 was cocrystallized with a proline-containing PPIase peptide substrate. In the complex, the peptide binds at the interface of a peptide-induced dimer interface. Conserved residues of the interdomain groove contribute to the peptide binding site and dimer interface. Structure-guided mutational studies showed that in vivo PTPA activity is influenced by mutations on the surface of the peptide binding pocket, the same mutations that also influenced the in vitro activation of PP2Ai and PPIase activity. 相似文献
47.
Harold J. G. Meijer Nullin Divecha Herman van den Ende Alan Musgrave Teun Munnik 《Planta》1999,208(2):294-298
Cells from several different plant species synthesised a polyphosphoinositide (PPI)-like lipid when osmo-stressed. Synthesis
was maximal after about 10 min and was stimulated by a variety of osmolytes. Using NaCl, the strongest response centred around
200 mM. The lipid was shown to be the novel PPI isomer phosphatidyl-inositol 3,5-bisphosphate [PtdIns-(3,5)P2] by analytical thin-layer chromatography and conversion to PtdIns(3,4,5)P3 using recombinant phosphoinositide 4-OH kinase. The results indicate that PtdIns-(3,5)P2 plays a role in a general osmo-signalling pathway in plants. Its potential role is discussed.
Received: 6 November 1998 / Accepted: 14 December 1998 相似文献
48.
Binding-protein expression is subject to temporal,developmental and stress-induced regulation in terminally differentiated soybean organs 总被引:3,自引:0,他引:3
Andrew Kalinski Daniel L. Rowley Deborah S. Loer Carolyn Foley George Buta Eliot M. Herman 《Planta》1995,195(4):611-621
Binding protein (BiP) is a widely distributed and highly conserved endoplasmic-reticulum luminal protein that has been implicated in cotranslational folding of nascent polypeptides, and in the recognition and disposal of misfolded polypeptides. Analysis of cDNA sequences and genomic blots indicates that soybeans (Glycine max L. Merr.) possess a small gene family encoding BiP. The deduced sequence of BiP is very similar to that of other plant BiPs. We have examined the expression of BiP in several different terminally differentiated soybean organs including leaves, pods and seed cotyledons. Expression of BiP mRNA increases during leaf expansion while levels of BiP protein decrease. Leaf BiP mRNA is subject to temporal control, exhibiting a large difference in expression in a few hours between dusk and night. The expression of BiP mRNA varies in direct correlation with accumulation of seed storage proteins. The hybridization suggests that maturing-seed BiP is likely to be a different isoform from vegetative BiPs. Levels of BiP protein in maturing seeds vary with BiP mRNA. High levels of BiP mRNA are detected after 3 d of seedling growth. Little change in either BiP mRNA or protein levels was detected in maturing soybean pods, although BiP-protein levels decrease in fully mature pods. Persistent wounding of leaves by whiteflies induces massive overexpression of BiP mRNA while only slightly increasing BiP-protein levels. In contrast single-event puncture wounding only slightly induces additional BiP expression above the temporal variations. These observations indicate that BiP is not constitutively expressed in terminally differentiated plant organs. Expression of BiP is highest during the developmental stages of leaves, pods and seeds when their constituent cells are producing seed or vegetative storage proteins, and appears to be subject to complex regulation, including developmental, temporal and wounding.The mention of vendor or product does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over vendors of similar products not mentioned.Abbreviations BiP
binding protein
The sequences reported in this paper have been submitted to Gen-Bank and are identified with the accession numbers BiP-A (U08384), BiP-B (U08383), BiP-C (U08382) and -1,3 glucanase (U08405). 相似文献
49.
Caberg JH Hubert P Herman L Herfs M Roncarati P Boniver J Delvenne P 《Cancer immunology, immunotherapy : CII》2009,58(1):39-47
Human papillomavirus (HPV) infection, particularly type 16, is causally associated with cancer of the uterine cervix. The
persistence or progression of cervical lesions suggests that viral antigens are not adequately presented to the immune system.
This hypothesis is reinforced by the observation that most squamous intraepithelial lesions (SILs) show quantitative and functional
alterations of Langerhans cells (LC). The infiltration of immature LC in the squamous epithelium is mainly controlled by Macrophage
Inflammatory Protein 3α/CCL20. After having shown that CCL20 production is altered in HPV-transformed keratinocytes (KC),
the possible role of HPV16 E6 and E7 viral oncoproteins in the reduced CCL20 levels observed in SILs was investigated by silencing
HPV16 E6 and E7 oncogenes by RNA interference (siRNA). This treatment not only increased CCL20 secretion but also resulted
in the modulation of NF-κB p50, p52 and p65 precursor localization. Moreover, silencing of E6 and E7 oncogenes in HPV16-transformed
KC induced a significantly higher migratory capacity of LC in a Boyden chamber assay and in an in vitro formed (pre)neoplastic
epithelium reminiscent of high-grade SILs. Anti-CCL20 neutralizing antibody experiments showed that the increased migration
of LC is due to the re-expression of CCL20 in E6 and E7 siRNA transfected KC. These data suggest that HPV16 E6/E7-induced
down-regulation of CCL20 observed during the cervical carcinogenesis may contribute to a diminished capacity of the immune
system to control HPV infection.
P. Hubert and J. H. Caberg contributed equally to this work. 相似文献
50.
Rodrigo A. F. Alvarenga Jo Dewulf Herman Van Langenhove Mark A. J. Huijbregts 《The International Journal of Life Cycle Assessment》2013,18(5):939-947