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991.
Tiziana Genovese Emanuela Esposito† Emanuela Mazzon Rosanna Di Paola Rocco Caminiti‡ Placido Bramanti Alessandro Cappelani§ Salvatore Cuzzocrea¶ 《Journal of neurochemistry》2009,108(6):1360-1372
Interleukin-10 (IL-10) exerts a wide spectrum of regulatory activities in the immune and inflammatory response. The aim of this study was to investigate the role of endogenous IL-10 on the modulation of the secondary events in mice subjected to spinal cord injury induced by the application of vascular clips (force of 24 g) to the dura via a four-level T5–T8 laminectomy. IL-10 wild-type mice developed severe spinal cord damage characterized by oedema, tissue damage and apoptosis (measured by Annexin-V, terminal deoxynucleotidyltransferase-mediated UTP end labeling staining, Bax, Bcl-2, and Fas-L expression). Immunohistochemistry demonstrated a marked increase of localization of TNF-α, IL-1β and S100β, while western blot analysis shown an increased immunoreactivity of inducible nitric oxide synthase in the spinal cord tissues. The absence of IL-10 in IL-10 KO mice resulted in a significant augmentation of all the above described parameters. We have also demonstrated that the genetic absence of IL-10 worsened the recovery of limb function when compared with IL-10 wild-type mice group (evaluated by motor recovery score). Taken together, our results clearly demonstrate that the presence of IL-10 reduces the development of inflammation and tissue injury events associated with spinal cord trauma. 相似文献
992.
E. de Mercado M. Hernandez E. Sanz A. Rodriguez E. Gomez J.M. Vazquez E.A. Martinez J. Roca 《Animal reproduction science》2009,115(1-4):149-157
The aim of the present study was to evaluate the protective effect of l-glutamine (l-Gln) against cryopreservation injuries on boar sperm. In Experiment 1, l-Gln from 20 to 80 mM was evaluated as a supplement for a standard freezing extender (egg yolk – EY – 20%, and glycerol 3%). No significant improvement (P > 0.05) was obtained for any post-thaw sperm parameter assessed (objective sperm motility – CASA system – and flow cytometric analysis of plasma and acrosomal membrane integrity −SYBR14/PI/PE-PNA− and plasma membrane stability −M540/YoPro1−). In Experiment 2, l-Gln was evaluated as a partial glycerol substitute in the freezing extender. Significant (P < 0.05) enhancement of post-thaw sperm motion parameters was achieved in sperm frozen in the presence of 2% glycerol and 80 mM l-Gln compared to control (3% glycerol). In Experiment 3, l-Gln was evaluated as an EY substitute in the freezing extender, and no functional sperm were recovered after thawing sperm frozen in the presence of l-Gln and the absence of EY. In conclusion, l-Gln has the ability to cryoprotect boar sperm when it is used as a partial glycerol substitute in the freezing extender. 相似文献
993.
Liliana Marum Joo Loureiro Eleazar Rodriguez Conceio Santos M. Margarida Oliveira Clia Miguel 《Journal of biotechnology》2009,143(4):288-295
An approach combining morphological profiling and flow cytometric analysis was used to assess genetic stability during the several steps of somatic embryogenesis in Pinus pinaster. Embryogenic cell lines of P. pinaster were established from immature zygotic embryos excised from seeds obtained from open-pollinated trees. During the maturation stage, phenotype of somatic embryos was characterized as being either normal or abnormal. Based upon the prevalent morphological traits, different types of abnormal embryos underwent further classification and quantification. Nuclear DNA content of maritime pine using the zygotic embryos was estimated to be 57.04 pg/2C, using propidium iodide flow cytometry. According to the same methodology, no significant differences (P ≤ 0.01) in DNA ploidy were detected among the most frequently observed abnormal phenotypes, embryogenic cell lines, zygotic and normal somatic embryos, and somatic embryogenesis-derived plantlets. Although the differences in DNA ploidy level do not exclude the occurrence of a low level of aneuploidy, the results obtained point to the absence of major changes in ploidy level during the somatic embryogenesis process of this economically important species. Therefore, our primary goal of true-to-typeness was assured at this level. 相似文献
994.
Giovanna Del Vecchio Alessandro Giuliani Mercedes Fernandez Pietro Mesirca Ferdinando Bersani Rosanna Pinto Lucia Ardoino Giorgio A. Lovisolo Luciana Giardino Laura Calzà 《Bioelectromagnetics》2009,30(7):564-572
In this work we tested viability, proliferation, and vulnerability of neural cells, after continuous radiofrequency (RF) electromagnetic fields exposure (global system for mobile telecommunications (GSM) modulated 900 MHz signal at a specific absorption rate (SAR) of 1 W/kg and maximum duration 144 h) generated by transverse electromagnetic cells. We used two cellular systems, SN56 cholinergic for example, SN56 cholinergic cell line and rat primary cortical neurons, and well‐known neurotoxic challenges, such as glutamate, 25‐35AA beta‐amyloid, and hydrogen peroxide. Exposure to RF did not change viability/proliferation rate of the SN56 cholinergic cells or viability of cortical neurons. Co‐exposure to RF exacerbated neurotoxic effect of hydrogen peroxide in SN56, but not in primary cortical neurons, whereas no cooperative effects of RF with glutamate and 25‐35AA beta‐amyloid were found. These data suggest that only under particular circumstances exposure to GSM modulated, 900 MHz signal act as a co‐stressor for oxidative damage of neural cells. Bioelectromagnetics 30:564–572, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
995.
Chiara Giommarelli Alessandro Corti Rosanna Supino Enrica Favini Aldo Paolicchi Alfonso Pompella Franco Zunino 《Free radical biology & medicine》2009,46(11):1516-1526
The cell ability of tumor cells to tolerate stress conditions is a typical feature of solid tumors. In particular, the resistance to oxidative stress of melanoma cells likely contributes to their intrinsic drug resistance. In an attempt to develop novel strategies for overcoming the mechanisms of cellular protection against oxidative stress, in this study we have explored the efficacy of the combination of two prooxidant agents in two human melanoma cell clones. The selected clones are characterized by a marked difference in expression of γ-glutamyltransferase, which is known to produce a persistent low level of oxidative stress resulting in the stimulation of protective systems. The γ-glutamyltransferase-overexpressing clone exhibited a low susceptibility to arsenic trioxide-induced apoptosis, associated with low reactive oxygen species induction and increased catalase activity. The combination of arsenic trioxide with subtoxic concentrations of ascorbic acid resulted in a sensitization to apoptotic cell death. The expression of protective mechanisms, in particular catalase activity, accounted for the behavior of the resistant clone. The sensitization achieved by the combination was associated with a cellular response involving the ASK1/p38 axis, which is implicated in the regulation of catalase expression and the activation of apoptotic signals. In conclusion, the results of our study provide evidence that a rational combination of prooxidant agents may be effective in overcoming cellular tolerance to oxidative stress. 相似文献
996.
997.
Protective effects of a carbon monoxide-releasing molecule (CORM-3) during hepatic cold preservation
M.D. Pizarro J.V. Rodriguez M.E. Mamprin B.J. Fuller B.E. Mann R. Motterlini E.E. Guibert 《Cryobiology》2009,58(3):248-255
There is increasing evidence that carbon monoxide (CO), a signaling molecule generated during the degradation of heme by heme oxygenase-1 (HO-1) in biological systems, has a variety of cytoprotective actions, including anti-hypoxic effects at low temperatures. However, during liver cold preservation, a direct effect needs to be established. Here, we designed a study to analyze the role of CO, delivered via a carbon monoxide-releasing molecule (CO-RM) in the maintenance of liver function, and integrity in rats during cold ischemia/reperfusion (CI/R) injury. We used an isolated normothermic perfused liver system (INPL) following a clinically relevant model of ex vivo 48 h cold ischemia stored in a modified University of Wisconsin (UW) solution, to determine the specific effects of CO in a rat model. CO was generated from 50 μM tricarbonylchloro ruthenium-glycinato (CORM-3), a water-soluble transition metal carbonyl that exerts pharmacological activities via the liberation of controlled amounts of CO in biological systems. The physiological effects of CORM-3 were confirmed by the parallel use of a specific inactive compound (iCORM-3), which does not liberate CO in the cellular environment.CORM-3 addition was found to prevent the injury caused by cold storage by improving significantly the perfusion flow during reperfusion (by almost 90%), and by decreasing the intrahepatic resistance (by 88%) when compared with livers cold preserved in UW alone. Also, CORM-3 supplementation preserved good metabolic capacity as indicated by hepatic oxygen consumption, glycogen content, and release of lactate dehydrogenase. Liver histology was also partially preserved by CORM-3 treatment.
Conclusions
These findings suggest that CO-RM could be utilized as adjuvant therapeutics in UW solutions to limit the injury sustained by donor livers during cold storage prior to transplantation, as has been similarly proposed for the heart, and kidney. 相似文献998.
Toshiko Tanaka Paul Scheet Betti Giusti Stefania Bandinelli Maria Grazia Piras Gianluca Usala Sandra Lai Antonella Mulas Anna Maria Corsi Anna Vestrini Francesco Sofi Anna Maria Gori Rosanna Abbate Jack Guralnik Andrew Singleton Goncalo R. Abecasis David Schlessinger Manuela Uda Luigi Ferrucci 《American journal of human genetics》2009,84(5):712
999.
Porcel EM Foose LL Svitova TF Blanch HW Prausnitz JM Radke CJ 《Biotechnology and bioengineering》2009,102(5):1330-1341
Nonionic and ionic surfactants diminish the initial rate of proteolysis of aqueous bovine serum albumin (BSA) by subtilisin Carlsberg. Surfactants studied include: nonionic tetraethylene glycol monododecyl ether (C12E4); anionic sodium dodecyl sulfate (SDS), anionic sodium dodecylbenzenesulfonate (SDBS), and cationic dodecyltrimethylamonium bromide (DTAB). Kinetic data are obtained using fluorescence emission. Special attention is given to enzyme kinetic specificity determined by fitting initial-rate data to the Michaelis-Menten model. All surfactants reduce the rate of proteolysis, most strongly at concentrations near and above the critical micelle concentration (CMC). Circular dichroism (CD), tryptophan/tyrosine fluorescence spectra, and tryptophan fluorescence thermograms indicate that BSA partially unfolds at ionic surfactant concentrations near and above the CMC. Changes in BSA conformation are less apparent at ionic surfactant concentrations below the CMC and for the nonionic surfactant C12E4. Subtilisin Carlsberg activity against the polypeptide, succinyl-Ala-Ala-Pro-Phe-p-nitroanilide, decreased due to enzyme-surfactant interaction. At the concentrations and time frames studied, there was no enzyme autolysis. Importantly, aqueous proteolysis rates are significantly reduced at high surfactant concentrations where protein-micellar-surfactant aggregates occur. To explain the negative effect of surfactant on subtilisin Carlsberg proteolytic activity against BSA, we propose that micelle/protein complexes hinder enzyme access. 相似文献
1000.