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11.
Calabrese V 《Free radical biology & medicine》2007,43(2):160-162
Amyotrophic lateral sclerosis (ALS) is a fatal motor neuron disease characterized by rapid degeneration of and loss of function in the motor cortex, brain stem, and spinal cord, particularly the anterior horn cells. Since the pioneering work of Brown and colleagues, more than 100 mutations in Cu,Zn superoxide dismutase (SOD1) have been described (P. Pasinelli, R. H. Brown, Nat. Rev. Neurosci.7, 710-723, 2006). There are toxic gain-of-function alterations in SOD1, because the enzymatic activity of this protein is not different in ALS from that of controls. The paper by Butterfield and colleagues reporting the use of redox proteomics to identify oxidatively modified proteins in the spinal cord in the G93A-SOD1 mouse model of familial amyotrophic lateral sclerosis was identified by the SCOPUS science literature information system to be one of the top 20 downloaded papers for 2005-2006 in Free Radical Biology and Medicine. Here my thoughts on the importance and impact of this paper are reported. 相似文献
12.
Before and below 'theory of mind': embodied simulation and the neural correlates of social cognition 总被引:11,自引:0,他引:11
Gallese V 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2007,362(1480):659-669
The automatic translation of folk psychology into newly formed brain modules specifically dedicated to mind-reading and other social cognitive abilities should be carefully scrutinized. Searching for the brain location of intentions, beliefs and desires-as such-might not be the best epistemic strategy to disclose what social cognition really is. The results of neurocognitive research suggest that in the brain of primates, mirror neurons, and more generally the premotor system, play a major role in several aspects of social cognition, from action and intention understanding to language processing. This evidence is presented and discussed within the theoretical frame of an embodied simulation account of social cognition. Embodied simulation and the mirror neuron system underpinning it provide the means to share communicative intentions, meaning and reference, thus granting the parity requirements of social communication. 相似文献
13.
Ahmadian G Degrassi G Venturi V Zeigler DR Soudi M Zanguinejad P 《Journal of applied microbiology》2007,103(4):1081-1089
AIMS: Isolation and characterization of chitinases from a halotolerant Bacillus pumilus. METHODS AND RESULTS: Bacillus pumilus strain SG2 was isolated from saline conditions. It is able to produce chitinase activity at high salt concentration. SDS-PAGE analysis of the B. pumilus SG2 culture supernatant showed two major bands that were induced by chitin. The amino acid sequence of the two proteins, designated ChiS and ChiL, showed a high homology with the chitinase of B. subtilis CHU26, and chitinase A of B. licheniformis, respectively. N-terminal signal peptide of both proteins was also determined. The molecular weight and isoelectric point of the chitinases were determined to be 63 and 74 kDa, and 4.5 and 5.1, for ChiS and ChiL respectively. The genes encoding for both chitinases were isolated and their sequence determined. The regulation of the chitinase genes is under the control of the catabolite repression system. CONCLUSIONS: Secreted chitinase genes and their flanking region on the genome of B. pumilus SG2 have been identified and sequenced. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report of a multiple chitinases-producing B. pumilus halotolerant strain. We have identified two chitinases by using a reverse genetics approach. The chitinases show resistance to salt. 相似文献
14.
Organic acidurias are genetic disorders of mitochondrial metabolism that lead to the accumulation of organic acids in tissues and biological fluids. It has been demonstrated that interaction of carnitine with the cellular coenzyme A (CoA) pool, through the production of acyl-carnitines, is potentially critical for maintaining normal cellular metabolism under condition of impaired acyl-CoA use and that exposure of humans and other mammals to ethanol leads to impairment of mitochondrial function. The aim of the present study was to evaluate the role of chronic administration of ethanol on urinary excretion of short-chain organic acids and endogenous carnitines in rats. The data reported show that chronic administration of ethanol significantly increases urinary excretion of propionate, methylmalonate, as well as free acetate, butyrate, pyruvate, lactate, and beta-hydroxybutyrate. Chronic administration of propranolol abolished ethanol-dependent accumulation of propionate, suggesting involvement of beta-adrenergic mechanisms. Increased formation of propionate and methylmalonate was associated with decreased plasma carnitine levels and with increased excretion of specific acyl-carnitines, corresponding to the accumulating acyl groups. Our data indicate that chronic alcohol ingestion induces increased excretion of selected organic acids and that the endogenous carnitine pool might exert a protective role against the deleterious effects of accumulating short-chain organic acids. 相似文献
15.
González JF Degrassi G Devescovi G De Vleesschauwer D Höfte M Myers MP Venturi V 《Journal of Proteomics》2012,75(18):5911-5919
Xanthomonas oryzae pv. oryzae (Xoo) is the second most important rice pathogen, causing a disease called bacterial leaf blight. Xoo colonizes and infects the vascular tissue resulting in tissue necrosis and wilting causing significant yield losses worldwide. In this study Xoo infected vascular fluid (xylem sap) was recovered and analyzed for secreted Xoo proteins. Three independent experiments resulted in the identification of 324 different proteins, 64 proteins were found in all three samples which included many of the known virulence-associated factors. In addition, 10 genes encoding for the identified proteins were inactivated and one mutant displayed statistically a significant loss in virulence when compared to the wild type Xoo, suggesting that a new virulence-associated factor has been revealed. The usefulness of this approach in understanding the lifestyle and unraveling the virulence-associated factors of phytopathogenic vascular bacteria is discussed. 相似文献
16.
Capsule Adoptions occurred at low rate (2.6% of successful nests and 1.1% of fledglings), probably as a result of a mistake in early offspring recognition. 相似文献
17.
We present the architecture of PROSIDIS, a special purpose co-processor designed to search for the occurrence of substrings similar to a given 'template string' within a proteome. Actual tests show speed up figures ranging from 5 to 50 with respect to conventional general-purpose processors. AVAILABILITY: the PROSIDIS configuration file and the c code are available at http://www.enea.it/hpcn/php/rosato/ 相似文献
18.
Athanasiou A Clarke AB Turner AE Kumaran NM Vakilpour S Smith PA Bagiokou D Bradshaw TD Westwell AD Fang L Lobo DN Constantinescu CS Calabrese V Loesch A Alexander SP Clothier RH Kendall DA Bates TE 《Biochemical and biophysical research communications》2007,364(1):131-137
Time-lapse microscopy of human lung cancer (H460) cells showed that the endogenous cannabinoid anandamide (AEA), the phyto-cannabinoid Δ-9-tetrahydrocannabinol (THC) and a synthetic cannabinoid HU 210 all caused morphological changes characteristic of apoptosis. Janus green assays of H460 cell viability showed that AEA and THC caused significant increases in OD 595 nm at lower concentrations (10-50 μM) and significant decreases at 100 μM, whilst HU 210 caused significant decreases at all concentrations. In rat heart mitochondria, all three ligands caused significant decreases in oxygen consumption and mitochondrial membrane potential. THC and HU 210 caused significant increases in mitochondrial hydrogen peroxide production, whereas AEA was without significant effect. All three ligands induced biphasic changes in either mitochondrial complex I activity and/or mitochondrial complex II-III activity. These data demonstrate that AEA, THC, and HU 210 are all able to cause changes in integrated mitochondrial function, directly, in the absence of cannabinoid receptors. 相似文献
19.
Colognesi I Pasquali V Foà A Renzi P Bernardi F Bertolucci C Pinotti M 《Chronobiology international》2007,24(2):305-313
It was recently reported that the circadian clock machinery controls plasma levels of factor (F) VII, the serine protease triggering blood coagulation. Here, by exploiting the mouse model, this study showed that variations of photoperiod (i.e., winter or summer conditions or simulated chronic jetlag conditions) have a strong impact on plasma FVII activity levels. Under conditions mimicking summer or winter photoperiods, FVII activity showed a clear 24 h rhythmicity. Interestingly, mean daily FVII activity levels were significantly reduced in mice exposed to summer photoperiods. Behavioral activity rhythms under both photoperiods were synchronized to LD cycles, and the amount of activity per 24 h was comparable. The authors also investigated the influence of chronic jetlag (CJL) on the FVII activity rhythms, which can be easily mimicked in mice through continuous abrupt shifts in the lighting schedule. The exposure of mice to simulated CJL of either consecutive westward or consecutive westward and eastward flights for 15 days did not abolish the behavioral activity rhythms but was associated with a period significantly different from 24 h. Intriguingly, both types of CJL exerted a strong influence on FVII activity rhythms, which were virtually suppressed. Moreover, the mean daily FVII activity was significantly lower in the CJL than in the winter photoperiod condition. Taken together, these findings in mice provide novel insights into the modulation of FVII activity levels, which might have implications for human pathophysiology. 相似文献
20.
Drug-induced expansion and differentiation of V gamma 9V delta 2 T cells in vivo: the role of exogenous IL-2 总被引:2,自引:0,他引:2
Casetti R Perretta G Taglioni A Mattei M Colizzi V Dieli F D'Offizi G Malkovsky M Poccia F 《Journal of immunology (Baltimore, Md. : 1950)》2005,175(3):1593-1598
Human Vgamma9Vdelta2 T cells recognize nonpeptidic Ags generated by the 1-deoxy-d-xylulose 5-phosphate (many eubacteria, algae, plants, and Apicomplexa) and mevalonate (eukaryotes, archaebacteria, and certain eubacteria) pathways of isoprenoid synthesis. The potent Vgamma9Vdelta2 T cell reactivity 1) against certain cancer cells or 2) induced by infectious agents indicates that therapeutic augmentations of Vgamma9Vdelta2 T cell activities may be clinically beneficial. The functional characteristics of Vgamma9Vdelta2 T cells from Macaca fascicularis (cynomolgus monkey) are very similar to those from Homo sapiens. We have found that the i.v. administration of nitrogen-containing bisphosphonate or pyrophosphomonoester drugs into cynomolgus monkeys combined with s.c. low-dose (6 x 10(5) U/animal) IL-2 induces a large pool of CD27+ and CD27- effector/memory T cells in the peripheral blood of treated animals. The administration of these drugs in the absence of IL-2 is substantially less effective, indicating the importance of additional exogenous costimuli. Shortly after the costimulatory IL-2 treatment, only gammadelta (but not alphabeta) T cells expressed the CD69 activation marker, indicating that Vgamma9Vdelta2 T lymphocytes are more responsive to low-dose IL-2 than alphabeta T cells. Up to 100-fold increases in the numbers of peripheral blood Vgamma9Vdelta2 T cells were observed in animals receiving the gammadelta stimulatory drug plus IL-2. Moreover, the expanded Vgamma9Vdelta2 T cells were potent Th1 effectors capable of releasing large amounts of IFN-gamma. These results may be relevant for designing novel (or modifying current) immunotherapeutic trials with nitrogen-containing bisphosphonate or pyrophosphomonoester drugs. 相似文献