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排序方式: 共有261条查询结果,搜索用时 15 毫秒
101.
102.
Wayne Murrell Emily Palmero John Bianco Biljana Stangeland Mrinal Joel Linda Paulson Bernd Thiede Zanina Grieg Ingunn Ramsnes H?vard K. Skjellegrind St?le Nyg?rd Petter Brandal Cecilie Sandberg Einar Vik-Mo Sheryl Palmero Iver A. Langmoen 《PloS one》2013,8(8)
The discovery of stem cells in the adult human brain has revealed new possible scenarios for treatment of the sick or injured brain. Both clinical use of and preclinical research on human adult neural stem cells have, however, been seriously hampered by the fact that it has been impossible to passage these cells more than a very few times and with little expansion of cell numbers. Having explored a number of alternative culturing conditions we here present an efficient method for the establishment and propagation of human brain stem cells from whatever brain tissue samples we have tried. We describe virtually unlimited expansion of an authentic stem cell phenotype. Pluripotency proteins Sox2 and Oct4 are expressed without artificial induction. For the first time multipotency of adult human brain-derived stem cells is demonstrated beyond tissue boundaries. We characterize these cells in detail in vitro including microarray and proteomic approaches. Whilst clarification of these cells’ behavior is ongoing, results so far portend well for the future repair of tissues by transplantation of an adult patient’s own-derived stem cells. 相似文献
103.
Nataša Vučinić Igor Djan Edita Stokić Biljana Božin Dragana Obreht Karmen Stankov Mihajla Djan 《Molecular biology reports》2014,41(8):5221-5227
The metabolic syndrome (MetS) is a polygenic multifactorial metabolic disorder with strong socioeconomic influence. MetS has became a worldwide epidemic, that directly increases the risk of cardiovascular diseases and type 2 diabetes mellitus. The human apoE gene, coding Apolipoprotein E, has three common polymorphisms in human population: e2, e3 and e4, which are proved to be associated with impaired lipid metabolism. The contribution of apoE polymorphism to MetS disorders has not been investigated previously in Vojvodina Province, region with the highest number of obese people in Serbia. The aim of this study was to evaluate apoE gene polymorphism in relation to MetS disorders. The healthy control group of 30 individuals and 63 MetS patients were examined for apoE variants in relation to biochemical and anthropometric parameters. The genotypes were determined by PCR–RFLP. Regarding all parameters, significantly higher values were detected in MetS group compared to control. The MetS group of patients had significantly higher frequency of e4 allele. In addition, positive relation was revealed between e4 allele presence and all measured parameters. It was found that the e4 allele was related with a significantly increased OR of MetS disorders according to the International Diabetes Federation definition. These results suggested that e4 allele may act as a one of determinants for development of metabolic syndrome. 相似文献
104.
Suzana Dinevska-Kjovkarovska Teuta Guladin Biljana Miova Slavco Mitev Katerina Gerazova 《Journal of thermal biology》2009
We examined the effect of acclimation to moderate hyperthermic environment on the ACTH, TSH, T3, T4 and corticosterone level, as well as the relative weight of hypophysis, thyroid and adrenal glands in streptozotocin-diabetic rats. Increased activity of the hypothalamo-pituitary-adrenocortical (HPA) axis has been demonstrated in diabetic animals, whereas insulin treatment restores the changes. Heat acclimation reduces the level of ACTH and corticosterone in control animals and moderates the hormonal disturbances caused by diabetes. Simultaneously, our study revealed impairment in the activity of the hypothalamo-pituitary-thyroid (HPT) axis. Acclimation to 35±1 °C resulted in significantly lower T3 and T4 levels in control, diabetic and insulin-treated animals. Relative weight of the hypophysis, thyroid and adrenal glands is decreased in heat-acclimated rats. Our assumption is that there might be a cross tolerance between diabetes and heat acclimation on a hormonal level. 相似文献
105.
Kukavica Biljana; Mojovic Milos; Vuccinic Zeljko; Maksimovic Vuk; Takahama Umeo; Jovanovic Sonja Veljovic 《Plant & cell physiology》2009,50(2):304-317
The hydroxyl radical produced in the apoplast has been demonstratedto facilitate cell wall loosening during cell elongation. Cellwall-bound peroxidases (PODs) have been implicated in hydroxylradical formation. For this mechanism, the apoplast or cellwalls should contain the electron donors for (i) H2O2 formationfrom dioxygen; and (ii) the POD-catalyzed reduction of H2O2to the hydroxyl radical. The aim of the work was to identifythe electron donors in these reactions. In this report, hydroxylradical (·OH) generation in the cell wall isolated frompea roots was detected in the absence of any exogenous reductants,suggesting that the plant cell wall possesses the capacity togenerate ·OH in situ. Distinct POD and Mn-superoxidedismutase (Mn-SOD) isoforms different from other cellular isoformswere shown by native gel electropho-resis to be preferably boundto the cell walls. Electron paramagnetic resonance (EPR) spectroscopyof cell wall isolates containing the spin-trapping reagent,5-diethoxyphosphoryl-5-methyl-1-pyrroline-N-oxide (DEPMPO),was used for detection of and differentiation between ·OHand the superoxide radical (O2–·). The data obtainedusing POD inhibitors confirmed that tightly bound cell wallPODs are involved in DEPMPO/OH adduct formation. A decreasein DEPMPO/OH adduct formation in the presence of H2O2 scavengersdemonstrated that this hydroxyl radical was derived from H2O2.During the generation of ·OH, the concentration of quinhydronestructures (as detected by EPR spectroscopy) increased, suggestingthat the H2O2 required for the formation of ·OH in isolatedcell walls is produced during the reduction of O2 by hydroxycinnamicacids. Cell wall isolates in which the proteins have been denaturated(including the endogenous POD and SOD) did not produce ·OH.Addition of exogenous H2O2 again induced the production of ·OH,and these were shown to originate from the Fenton reaction withtightly bound metal ions. However, the appearance of the DEPMPO/OOHadduct could also be observed, due to the production of O2–·when endogenous SOD has been inactivated. Also, O2–·was converted to ·OH in an in vitro horseradish peroxidase(HRP)/H2O2 system to which exogenous SOD has been added. Takentogether with the discovery of the cell wall-bound Mn-SOD isoform,these results support the role of such a cell wall-bound SODin the formation of ·OH jointly with the cell wall-boundPOD. According to the above findings, it seems that the hydroxycinnamicacids from the cell wall, acting as reductants, contribute tothe formation of H2O2 in the presence of O2 in an autocatalyticmanner, and that POD and Mn-SOD coupled together generate ·OHfrom such H2O2. 相似文献
106.
Biljana ?. Gliši? 《Bioorganic chemistry》2010,38(4):144-10290
Proton NMR spectroscopy was applied to study the reactions of the dipeptides glycyl-glycine (Gly-Gly) and glycyl-l-alanine (Gly-l-Ala) with hydrogen tetrachloridoaurate(III) (H[AuCl4]). All reactions were performed at pH 2.0 and 3.0 and at 40 °C. The final products in these reactions were [Au(Gly-Gly-κ3NG1,NG2,OG2)Cl] and [Au(Gly-l-Ala-κ3NG,NA,OA)Cl] complexes. Tridentate coordination of the corresponding dipeptides and square-planar geometry of these Au(III) complexes was confirmed by NMR (1H and 13C) spectroscopy. This study showed that at pH < 3.0 the Au(III) ion was able to deprotonate the amide nitrogen atom. However this displacement reaction was very slow and the total concentration of the corresponding Au(III)-peptide complex formed after 5 days was less than 60% for the Gly-l-Ala or 70% for the Gly-Gly dipeptide. The kinetic data of the reactions between the Gly-Gly and Gly-l-Ala dipeptides and [AuCl4]− were compared with those for the histidine-containing Gly-l-His dipeptide. The differences in the reactivity of these three dipeptides with the Au(III) ion are discussed. 相似文献
107.
Cara K. Bradley Omar Chami Teija T. Peura Alexis Bosman Biljana Dumevska Uli Schmidt Tomas Stojanov 《In vitro cellular & developmental biology. Animal》2010,46(3-4):294-299
Human embryonic stem cells are pluripotent cells capable of extensive self-renewal and differentiation to all cells of the embryo proper. Here, we describe the derivation and characterization of three Sydney IVF human embryonic stem cell lines not already reported elsewhere, designated SIVF001, SIVF002, and SIVF014. The cell lines display typical compact colony morphology of embryonic stem cells, have stable growth rates over more than 40 passages and are cytogenetically normal. Furthermore, the cell lines express pluripotency markers including Nanog, Oct4, SSEA3 and Tra-1-81, and are capable of generating teratoma cells derived from each of the three germ layers in immunodeficient mice. These experiments show that the cell lines constitute pluripotent stem cell lines. 相似文献
108.
Veljovic-Jovanovic S Kukavica B Stevanovic B Navari-Izzo F 《Journal of experimental botany》2006,57(8):1759-1768
Ramonda sp. (Gesneriaceae) is an endemic and relic plant ina very small group of poikilohydric angiosperms that are ableto survive in an almost completely dehydrated state. Senescence-and drought-related changes in the activity of peroxidase (POD;EC 1.11.1.7
[EC]
), ascorbate peroxidase (EC 1.11.1.11
[EC]
), and superoxidedismutase (SOD; EC 1.15.1.1
[EC]
) were determined in leaves of differentage and relative water content. The results indicate that differentPOD isoforms were stimulated during senescence and dehydration.Two of the soluble POD isoforms were anionic with pI 4.5, andtwo were cationic with pI 9.3 and 9.0. The activity of ascorbateperoxidase remained unchanged either by drought or senescence.For the first time, SOD isoforms have now been determined inthis resurrection plant. Several SOD isoforms, all of the Mntype, were found to be anionic with pI 4 and a few others hadpI from 5 to 6, while one band of FeSOD with a lower molecularweight was neutral. Rehydration brought about a remarkable decreaseover the first hour in the activity of all the antioxidant enzymesexamined but activity recovered 1 d after rehydration. The resultsconfirmed that dehydration and senescence caused disturbancein the redox homeostasis of Ramonda leaves, while inducing differentPOD isoforms. A physiological role of peroxidase reaction withhydroxycinnamic acids in conservation and protection of cellularconstituents of desiccated Ramonda leaves is suggested. Key words: Desiccation, peroxidase, Ramonda, senescence, superoxide dismutase 相似文献
109.
Surface expression of ASIC2 inhibits the amiloride-sensitive current and migration of glioma cells 总被引:3,自引:0,他引:3
110.
Balen B Krsnik-Rasol M Zamfir AD Milosević J Vakhrushev SY Peter-Katalinić J 《Journal of proteome research》2006,5(7):1658-1666
The structure elucidation of protein-linked N-glycans in plants has raised interest in the past years due to remarkable physiological roles attributed to these modifications. However, little information about the glycoprotein patterns related to plant cell differentiation, dedifferentiation and transformation is available. In this work, the use of two-dimensional polyacrylamide gel electrophoresis in conjunction with matrix assisted laser/desorption ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS) for the characterization of carbohydrates released from plant glycoproteins is described. Proteins from different Mammillaria tissues (shoot, callus, hyperhydric regenerant, and TW tumor) were separated by 2D SDS-polyacrylamide gel electrophoresis, transferred to a nitrocellulose membrane and incubated with Con A to detect N-glycosylated proteins. To discover if the same protein can have various N-glycan structures depending on the organization status of the tissue, the selected glycoprotein spot, which was common for all investigated tissues, was excised from the gels and digested by PNGase A. The released oligosaccharides were analyzed by MALDI-TOF-MS. The results obtained in this study indicate that the N-glycosylation pattern of the protein is clearly dependent on level of plant tissue organization and can be related to the specific morphogenic status. 相似文献