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排序方式: 共有193条查询结果,搜索用时 15 毫秒
1.
Blanca Domenech‐Ximenos Victor Cuba Pepus Daunis‐i‐Estadella Santiago Thi‐Henestrosa Francisco Jaldo Carles Biarnes Xavier Molina Gemma Xifra Wifredo Ricart Anton Bardera Imma Boada Marco Essig Salvador Pedraza Massimo Federici Jos Manuel Fernndez‐Real Josep Puig 《Obesity (Silver Spring, Md.)》2020,28(9):1663-1670
2.
GUSTAVO BRUGES ADOLFO BORGES SINAI SÁNCHEZ DE VILLARROEL ITALA LIPPO DE BÉCEMBERG GISELA FRANCIS DE TOBA FABIOLA PLÁCERES 《Journal of receptor and signal transduction research》2013,33(2-3):189-216
Muscarinic activation of tracheal smooth muscle (TSM) involves a M3AChR/heterotrimeric-G protein/NPR-GC coupling mechanism. G protein activators Mastoparan (MAS) and Mastoparan-7 stimulated 4- and 10-fold the NPR-GC respectively, being insensitive to PTX and antibodies against Gαi/o subfamily. Muscarinic and MAS stimulation of NPR-GC was blocked by antibodies against C-terminal of Gαq16, whose expression was confirmed by RT-PCR. However, synthetic peptides from C-terminal of Gαq15/16 stimulated the NPR-GC. Coupling of αq16 to M3AChR is supported by MAS decreased [3H]QNB binding, being abolished after M3AChR-4-DAMP-alkylation. Anti-i3M3AChR antibodies blocked the muscarinic activation of NPR-GC, and synthetic peptide from i3M3AChR (M3P) was more potent than MAS increasing GTPγ [35S] and decreasing the [3H]QNB activities. Coupling between NPR-GC and Gαq16 was evaluated by using trypsin-solubilized-fraction from TSM membranes, which displayed a MAS-sensitive-NPR-GC activity, being immunoprecipitated with anti-Gαq16, also showing an immunoreactive heterotrimeric-G-β -subunit. These data support the existence of a novel transducing cascade, involving Gαq16β γ coupling M3AChR to NPR-GC. 相似文献
3.
Antony?P?Martin William?M?Palmer Caitlin?S?Byrt Robert?T?Furbank Christopher?PL?GrofEmail author 《Biotechnology for biofuels》2013,6(1):186
Background
A major hindrance to the development of high yielding biofuel feedstocks is the ability to rapidly assess large populations for fermentable sugar yields. Whilst recent advances have outlined methods for the rapid assessment of biomass saccharification efficiency, none take into account the total biomass, or the soluble sugar fraction of the plant. Here we present a holistic high-throughput methodology for assessing sweet Sorghum bicolor feedstocks at 10 days post-anthesis for total fermentable sugar yields including stalk biomass, soluble sugar concentrations, and cell wall saccharification efficiency.Results
A mathematical method for assessing whole S. bicolor stalks using the fourth internode from the base of the plant proved to be an effective high-throughput strategy for assessing stalk biomass, soluble sugar concentrations, and cell wall composition and allowed calculation of total stalk fermentable sugars. A high-throughput method for measuring soluble sucrose, glucose, and fructose using partial least squares (PLS) modelling of juice Fourier transform infrared (FTIR) spectra was developed. The PLS prediction was shown to be highly accurate with each sugar attaining a coefficient of determination (R 2 ) of 0.99 with a root mean squared error of prediction (RMSEP) of 11.93, 5.52, and 3.23 mM for sucrose, glucose, and fructose, respectively, which constitutes an error of <4% in each case. The sugar PLS model correlated well with gas chromatography–mass spectrometry (GC-MS) and brix measures. Similarly, a high-throughput method for predicting enzymatic cell wall digestibility using PLS modelling of FTIR spectra obtained from S. bicolor bagasse was developed. The PLS prediction was shown to be accurate with an R 2 of 0.94 and RMSEP of 0.64 μg.mgDW-1.h-1.Conclusions
This methodology has been demonstrated as an efficient and effective way to screen large biofuel feedstock populations for biomass, soluble sugar concentrations, and cell wall digestibility simultaneously allowing a total fermentable yield calculation. It unifies and simplifies previous screening methodologies to produce a holistic assessment of biofuel feedstock potential.4.
Lorena Pedraza Araceli Flores Hector Toribio Rodolfo Quintero Sylvie Le Borgne Cessna Moss-Acosta Alfredo Martinez 《Bioenergy Research》2016,9(4):1046-1052
Interest in the use of corncobs as feedstock for bioethanol production is growing. This study assesses the feasibility of sequential thermochemical diluted sulfuric acid pretreatment of corncobs at moderate temperature to hydrolyze the hemicellulosic fraction, followed by enzymatic hydrolysis of the whole slurry, and fermentation of the obtained syrup. The total sugar concentration after enzymatic hydrolysis was 85.21 g/l, i.e., 86 % of the sugars were liberated from the polymeric fractions, together with a low amount of furfural (0.26 g/l) and 4.01 g/l of acetic acid. The syrups, which contained 36.3, 40.9, 4.47, and 1.84 g/l of xylose, glucose, arabinose, and mannose, respectively, were fermented (pH 7, 37 °C, 150 rpm) to ethanol with the metabolically engineered acetate-tolerant Escherichia coli strain MS04 under non-aerated conditions, producing 35 g/l of ethanol in 18 h (1.94 gEtOH/l/h), i.e., a conversion yield greater than 80 % of the theoretical value based on total sugars was obtained. Hence, using the procedures developed in this study, 288 l of ethanol can be produced per metric ton of dry corncobs. Strain MS04 can ferment sugars in the presence of acetate, and the amount of furans generated during the sequential thermochemical and enzymatic hydrolysis was low; hence, the detoxification step was avoided. The residual salts, acetic acid, and solubilized lignin present in the syrup did not interfere with the production of ethanol by E. coli MS04 and the results show that this strain can metabolize mixtures of glucose and xylose simultaneously. 相似文献
5.
Adenovirus-mediated expression of caveolin-1 in mouse liver increases plasma high-density lipoprotein levels 总被引:3,自引:0,他引:3
Caveolae are 50-100 nm plasma membrane invaginations, which function in cell signaling and transcytosis, as well as in regulating cellular cholesterol homeostasis. These subcompartments of the plasma membrane are characterized by the presence of caveolin proteins. Recent studies have indicated that caveolae may be involved in the regulation of cellular cholesterol efflux to HDL, as well as selective uptake mediated by SR-BI. In the present study, we have determined the effect of caveolin-1 overexpression in mouse liver on plasma lipoprotein metabolism. We evaluated this effect using an adenovirus-mediated gene delivery system. C57BL/6J mice were injected with adenoviruses encoding either caveolin-1 (Adcav-1) or green fluorescent protein (AdGFP) together with a transactivator adenovirus (AdtTA). We found that, after adenovirus injection, caveolin-1 was overexpressed in hepatocytes. Moreover, the recombinant protein was localized to the plasma membrane. We also found that caveolin-1 overexpression induced a marked change in the lipoprotein profile of injected animals. In caveolin-1 overexpressing animals, plasma HDL-cholesterol levels were found to be approximately 2-fold elevated, as compared with control animals. To determine the effect of caveolin-1 on SR-BI-mediated selective uptake, we infected murine hepatocytes in culture with an adenoviral vector carrying the caveolin-1 cDNA or GFP as a control protein. We show that, in primary cultures of hepatocytes, caveolin-1 inhibits DiI-HDL uptake mediated by SR-BI. This result would mechanistically explain the increased plasma HDL-cholesterol levels we observed in caveolin-1 adenovirus-injected animals. In addition, caveolin-1 expression increased the secretion of apolipoprotein A-I in cultured hepatocytes and increased apolipoprotein A-I plasma levels in mice. Our study therefore demonstrates an important role for caveolin-1 in regulating HDL metabolism. 相似文献
6.
Santamaría A Flores-Escartín A Martínez JC Osorio L Galván-Arzate S Pedraza-Chaverrí J Chaverrí JP Maldonado PD Medina-Campos ON Jiménez-Capdeville ME Manjarrez J Ríos C 《Free radical biology & medicine》2003,35(4):418-427
Reactive oxygen species and oxidative stress are involved in quinolinic acid (QUIN)-induced neurotoxicity. QUIN, a N-methyl-D-aspartate receptor (NMDAr) agonist and prooxidant molecule, produces NMDAr overactivation, excitotoxic events, and direct reactive oxygen species formation. Copper is an essential metal exhibiting both modulatory effects on neuronal excitatory activity and antioxidant properties. To investigate whether this metal is able to counteract the neurotoxic and oxidative actions of QUIN, we administered copper (as CuSO(4)) intraperitoneally to rats (2.5, 5.0, 7.5, and 10.0 mg/kg) 30 min before the striatal infusion of 1 microliter of QUIN (240 nmol). A 5.0 mg/kg CuSO(4) dose significantly increased the copper content in the striatum, reduced the neurotoxicity measured both as circling behavior and striatal gamma-aminobutyric acid (GABA) depletion, and blocked the oxidative injury evaluated as striatal lipid peroxidation (LP). In addition, copper reduced the QUIN-induced decreased striatal activity of Cu,Zn-dependent superoxide dismutase, and increased the ferroxidase activity of ceruloplasmin in cerebrospinal fluid from QUIN-treated rats. However, copper also produced significant increases of plasma lactate dehydrogenase activity and mortality at the highest doses employed (7.5 and 10.0 mg/kg). These results show that at low doses, copper exerts a protective effect on in vivo QUIN neurotoxicity. 相似文献
7.
Bibliography
Bibliography 相似文献8.
9.
José-Fernando Camacho-Vallejo Julio Mar-Ortiz Francisco López-Ramos Ricardo Pedraza Rodríguez 《PloS one》2015,10(6)
Local access networks (LAN) are commonly used as communication infrastructures which meet the demand of a set of users in the local environment. Usually these networks consist of several LAN segments connected by bridges. The topological LAN design bi-level problem consists on assigning users to clusters and the union of clusters by bridges in order to obtain a minimum response time network with minimum connection cost. Therefore, the decision of optimally assigning users to clusters will be made by the leader and the follower will make the decision of connecting all the clusters while forming a spanning tree. In this paper, we propose a genetic algorithm for solving the bi-level topological design of a Local Access Network. Our solution method considers the Stackelberg equilibrium to solve the bi-level problem. The Stackelberg-Genetic algorithm procedure deals with the fact that the follower’s problem cannot be optimally solved in a straightforward manner. The computational results obtained from two different sets of instances show that the performance of the developed algorithm is efficient and that it is more suitable for solving the bi-level problem than a previous Nash-Genetic approach. 相似文献
10.
Thibaud Souter Raphael Cornette Julio Pedraza John Hutchinson Michel Baylac 《Comptes Rendus Palevol》2010,9(6-7):411-422
Geometric morphometrics involves defining landmark points to generate a discrete representation of an object. This crucial step is strongly influenced by the biological question guiding the analysis, and even more when using curve and surface semi-landmarks methods, because these require to generate a template of reference. We exemplify these constraints using two datasets from projects with very different backgrounds. The Theropod Dataset is a functional morphometric analysis of different extinct and extant theropod pelves. The Shrew Dataset is a populational morphometric analysis of the white-toothed shrew with very small variations in skull shape. We propose a novel procedure to generate a regular template configuration, using polygonal modelling tools. This method allows us to control the template geometry and adapt its complexity to the morphological variation in the sample. More studies are necessary to assess the morphometric and statistical importance of template design in curve and surface analyses. 相似文献