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61.
Gildas Gueret Francois Lion Nathalie Guriec Josiane Arvieux Annabelle Dovergne Catherine Guennegan Eric Bezon Raoul Baron Jean-Luc Carre Charles Arvieux 《Cytokine》2009,45(2):92-98
Background: Acute renal dysfunction (ARD) is common after cardiac surgery with cardiopulmonary bypass (CPB). CPB results in a sudden systemic inflammatory response. Systemic and local pro-inflammatory cytokines synthesis has been linked with sub-clinical renal injury, especially tubular lesions. Therefore, we sought to assess the systemic synthesis pro-inflammatory cytokines and its association with perioperative ARD after cardiac surgery with CPB. Methods: Sixty-two patients undergoing cardiac surgery with CPB were prospectively included. Four groups of patients were defined according to blood creatinine increase: no ARD (less than 25% increase), faint ARD (25–50% increase), moderate ARD (50–100% increase), severe ARD (more than 100% increase). Results: Within the 48 post-operative hours was ARD observed as no dysfunction (41.9%), faint (32.2%), moderate (16.1%), severe (9.6%). One patient had to undergo a dialysis. Pre-operative characteristics were homogenous between the four groups excepted the left ventricle ejection fraction. ARD was associated with a low urinary output with high sodium excretion fraction. Significant increase of IL-6 level occurred when patients underwent a severe ARD despite no significant differences for the CRP and TNF-α concentrations. Conclusion: Severe acute renal dysfunction after cardiac surgery with CPB is associated with a significant increased IL-6 systemic production. 相似文献
62.
Combining physiological threshold knowledge to species distribution models is key to improving forecasts of the future niche for macroalgae 下载免费PDF全文
Brezo Martínez Francisco Arenas Alba Trilla Rosa M. Viejo Francisco Carreño 《Global Change Biology》2015,21(4):1422-1433
Species distribution models (SDM) are a useful tool for predicting species range shifts in response to global warming. However, they do not explore the mechanisms underlying biological processes, making it difficult to predict shifts outside the environmental gradient where the model was trained. In this study, we combine correlative SDMs and knowledge on physiological limits to provide more robust predictions. The thermal thresholds obtained in growth and survival experiments were used as proxies of the fundamental niches of two foundational marine macrophytes. The geographic projections of these species’ distributions obtained using these thresholds and existing SDMs were similar in areas where the species are either absent‐rare or frequent and where their potential and realized niches match, reaching consensus predictions. The cold‐temperate foundational seaweed Himanthalia elongata was predicted to become extinct at its southern limit in northern Spain in response to global warming, whereas the occupancy of southern‐lusitanic Bifurcaria bifurcata was expected to increase. Combined approaches such as this one may also highlight geographic areas where models disagree potentially due to biotic factors. Physiological thresholds alone tended to over‐predict species prevalence, as they cannot identify absences in climatic conditions within the species’ range of physiological tolerance or at the optima. Although SDMs tended to have higher sensitivity than threshold models, they may include regressions that do not reflect causal mechanisms, constraining their predictive power. We present a simple example of how combining correlative and mechanistic knowledge provides a rapid way to gain insight into a species’ niche resulting in consistent predictions and highlighting potential sources of uncertainty in forecasted responses to climate change. 相似文献
63.
Roberto Carre?o Wells S. Brown Dan Li Jessica A. Hernandez Yang Wang Tae Kon Kim John W. Craft Jr Krishna V. Komanduri Laszlo G. Radvanyi Patrick Hwu Jeffrey J. Molldrem Glen B. Legge Bradley W. McIntyre Qing Ma 《The Journal of biological chemistry》2010,285(43):32860-32868
The activation of leukocyte function-associated antigen-1 (LFA-1) plays a critical role in regulating immune responses. The metal ion-dependent adhesion site on the I-domain of LFA-1 αL subunit is the key recognition site for ligand binding. Upon activation, conformation changes in the I-domain can lead LFA-1 from the low affinity state to the high affinity (HA) state. Using the purified HA I-domain locked by disulfide bonds for immunization, we developed an mAb, 2E8, that specifically binds to cells expressing the HA LFA-1. The surface plasmon resonance analysis has shown that 2E8 only binds to the HA I-domain and that the dissociation constant (KD) for HA I-domain is 197 nm. The binding of 2E8 to the HA I-domain is metal ion-dependent, and the affinity decreased as Mn2+ was replaced sequentially by Mg2+ and Ca2+. Surface plasmon resonance analysis demonstrates that 2E8 inhibits the interaction of HA I-domain and ICAM-1. Furthermore, we found that 2E8 can detect activated LFA-1 on both JY and Jurkat cells using flow cytometry and parallel plate adhesion assay. In addition, 2E8 inhibits JY cell adhesion to human umbilical vein endothelial cells and homotypic aggregation. 2E8 treatment reduces the proliferation of both human CD4+ and CD8+ T cells upon OKT3 stimulation without the impairment of their cytolytic function. Taken together, these data demonstrate that 2E8 is specific for the high affinity form of LFA-1 and that 2E8 inhibits LFA-1/ICAM-1 interactions. As a novel activation-specific monoclonal antibody, 2E8 is a potentially useful reagent for blocking high affinity LFA-1 and modulating T cell activation in research and therapeutics. 相似文献
64.
Fruit size and seedlessness are highly relevant traits in many fruit crop species, and both are primary targets of breeding programs for table grapes. In this work we performed a quantitative genetic analysis of size and seedlessness in an F1 segregating population derived from the cross between a classical seeded (Vitis vinifera L. 'Dominga') and a newly bred seedless ('Autumn Seedless') cultivar. Fruit size was scored as berry weight (BW), and for seedlessness we considered both seed fresh weight (SFW) and the number of seeds and seed traces (SN) per berry. Quantitative trait loci (QTL) analysis of BW detected 3 QTLs affecting this trait and accounting for up to 67% of the total phenotypic variance. QTL analysis for seedlessness detected 3 QTLs affecting SN (explaining up to 35% of total variance) and 6 affecting SFW (explaining up to 90% of total variance). Among them, a major effect QTL explained almost half of the phenotypic variation for SFW. Comparative analysis of QTLs for these traits reduced the number of grapevine genomic regions involved, one of them being a major effect QTL for seedlessness. Association analyses showed that microsatellite locus VMC7F2, closely linked to this QTL, is a useful marker for selection of seedlessnes. 相似文献
65.
Carreño-Lopez R Campos-Reales N Elmerich C Baca BE 《Molecular & general genetics : MGG》2000,264(4):521-530
Disruption of ipdC, a gene involved in indole-3-acetic acid (IAA) production by the indole pyruvate pathway in Azospirillum brasilense Sp7, resulted in a mutant strain that was not impaired in IAA production with lactate or pyruvate as the carbon source. A tryptophan auxotroph that is unable to convert indole to tryptophan produced IAA if tryptophan was present but did not synthesise IAA from indole. Similar results were obtained for a mutant strain with additional mutations in the genes ipdC and trpD. This suggests the existence of an alternative Trp-dependent route for IAA synthesis. On gluconate as a carbon source, IAA production by the ipdC mutant was inhibited, suggesting that the alternative route is regulated by catabolite repression. Using permeabilised cells we observed the enzymatic conversion of tryptamine and indole-3-acetonitrile to IAA, both in the wild-type and in the ipdC mutant. IAA production from tryptamine was strongly decreased when gluconate was the carbon source. 相似文献
66.
Quantification of the differential cell count and total number of cells recovered from the lower respiratory tract by bronchoalveolar lavage is a valuable technique for the diagnostic study of interstitial lung diseases. To examine the effect on the cell counts of different methods of processing the lavage fluid, two comparisons were performed. First, two methods of differential cell counting were compared using 28 fluids. One count was performed in a Malassez hemocytometer after incubation of the living cells with neutral red for five minutes at room temperature; large cells and some small cells that had incorporated neutral red were identified as macrophages. Another count was performed on cytocentrifuge preparations made using the Shandon Cytospin I and Cytospin II and stained by the May-Grünwald-Giemsa method. The percentage of cells identified as lymphocytes was significantly lower on the cytocentrifuge preparations than with the Malassez hemocytometer. In the second study, the differential cell counts on smears prepared by the two types of cytocentrifuge (Cytospin I and Cytospin II) were compared for 32 bronchoalveolar lavage fluids. The percentage of small cells (especially lymphocytes) was lower on preparations made with the Cytospin I than on those made with the Cytospin II, but the difference was not significant. The results indicate that (1) cytocentrifugation of bronchoalveolar lavage fluids does result in a significant loss of small cells, especially lymphocytes, and (2) this loss is not significantly lessened by the use of the Cytospin II. 相似文献
67.
Flores-García M Fernández-G JM León-Martínez M Hernández-Ortega S Pérez-Méndez O Correa-Basurto J Carreón-Torres E Tolentino-López LE Ceballos-Reyes GM de la Peña-Díaz A 《Steroids》2012,77(5):512-520
Compounds with estrogenic effects that also inhibit platelet aggregation might be useful in reducing thrombotic events associated with estrogenic therapy. In this study, two aminoestrogens, Buame [N-(3-hydroxy-1,3,5(10)-estratrien-17β-yl)-butylamine] and Diebud [N,N'-bis-(3-hydroxy-1,3,5(10)-estratrien-17β-yl)-1,4-butanediamine], were synthesized and characterized using common analytical methods and spectrophotometric analyses. The location and orientation of these molecules on the estrogenic receptor α (ERα) were also evaluated. Platelet inhibitory effects were elucidated ADP-induced platelet aggregation and ADP- and collagen-induced ATP release. Molecular docking demonstrated that Buame can reach and bind to the ERα in the ligand binding domain (LBD) similar to 17β-estradiol (co-crystallized ligand). On the other hand, Diebud binds only to the surface of ERα due to its high molecular volume compared to 17β-estradiol and Buame. 相似文献
68.
Existence of distinct GB virus C/hepatitis G virus variants with different tropism 总被引:3,自引:0,他引:3 下载免费PDF全文
Fogeda M López-Alcorocho JM Bartolomé J Arocena C Martín MA Carreño V 《Journal of virology》2000,74(17):7936-7942
69.
PIQET: the design and development of an online ‘streamlined’ LCA tool for sustainable packaging design decision support 总被引:1,自引:0,他引:1
Karli L. Verghese Ralph Horne Andrew Carre 《The International Journal of Life Cycle Assessment》2010,15(6):608-620
Background, aim and scope
‘Streamlined’ life cycle assessment (LCA) tools hold out the possibility of providing LCA information quickly and easily in order to support a variety of decision-making environments and situations. The utility of such tools is closely related to the accuracy needs and possibilities, and the particular decisions to be supported. In order to facilitate the provision and application of LCA information in decision making during packaging design, development and utilisation, there is a prima facia case for a ‘streamlined’ LCA tool, provided it meets a set of requirements, including functionality, accuracy, validity, reliability and usability. 相似文献70.
Villanueva S Escobar P Jacubovsky I Irarrázabal C Carreño JE Erpel JM Céspedes C González AA Vio CP Velarde V 《Biological research》2012,45(1):51-60
Acute renal failure (ARF) can be caused by injuries that induce tissue hypoxia, which in turn can trigger adaptive or inflammatory responses. We previously showed the participation of basic fibroblast growth factor (FGF-2) in renal repair. Based on this, the aim of this study was to analyze the effect of FGF-2 signaling pathway manipulation at hypoxia-induced protein levels, as well as in key proteins from the vasoactive systems of the kidney. We injected rat kidneys with FGF-2 recombinant protein (r-FGF) or FGF-2 receptor antisense oligonucleotide (FGFR2-ASO) after bilateral ischemia, and evaluated the presence of iNOS, EPO and HO-1, in representation of hypoxia-induced proteins, as well as COX-2, renin, kallikrein, and B2KR, in representation of the vasoactive systems of the kidney. A reduction in iNOS, HO-1, EPO, renin, kallikrein, B2KR, and in renal damage was observed in animals treated with r-FGF. The opposite effect was found with FGF-2 receptor down-regulation. In contrast, COX-2 protein levels were higher in kidneys treated with r-FGF and lower in those that received FGFR2-ASO, as compared to saline treated kidneys. These results suggest that the protective role of FGF-2 in the pathogenesis of ARF induced by I/R is a complex process, through which a differential regulation of metabolic pathways takes place. 相似文献