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81.
Elisabet Cantó Esther Garcia Planella Carlos Zamora-Atenza Juan Camilo Nieto Jordi Gordillo Ma Angels Ortiz Isidoro Metón Elena Serrano Esteban Vegas Orlando García-Bosch Cándido Juárez Sílvia Vidal 《PloS one》2014,9(4)
The exact function of interleukin-19 (IL-19) on immune response is poorly understood. In mice, IL-19 up-regulates TNFα and IL-6 expression and its deficiency increases susceptibility to DSS-induced colitis. In humans, IL-19 favors a Th2 response and is elevated in several diseases. We here investigate the expression and effects of IL-19 on cells from active Crohn’s disease (CD) patient. Twenty-three active CD patients and 20 healthy controls (HC) were included. mRNA and protein IL-19 levels were analyzed in monocytes. IL-19 effects were determined in vitro on the T cell phenotype and in the production of cytokines by immune cells. We observed that unstimulated and TLR-activated monocytes expressed significantly lower IL-19 mRNA in active CD patients than in HC (logFC = −1.97 unstimulated; −1.88 with Pam3CSK4; and −1.91 with FSL-1; p<0.001). These results were confirmed at protein level. Exogenous IL-19 had an anti-inflammatory effect on HC but not on CD patients. IL-19 decreased TNFα production in PBMC (850.7±75.29 pg/ml vs 2626.0±350 pg/ml; p<0.01) and increased CTLA4 expression (22.04±1.55% vs 13.98±2.05%; p<0.05) and IL-4 production (32.5±8.9 pg/ml vs 13.5±2.9 pg/ml; p<0.05) in T cells from HC. IL-10 regulated IL-19 production in both active CD patients and HC. We observed that three of the miRNAs that can modulate IL-19 mRNA expression, were up-regulated in monocytes from active CD patients. These results suggested that IL-19 had an anti-inflammatory role in this study. Defects in IL-19 expression and the lack of response to this cytokine could contribute to inflammatory mechanisms in active CD patients. 相似文献
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85.
Estimates of tag retention and tagging-related mortality are essential for mark-recapture experiments. Mortality and tag loss were estimated from 15 tigerfish Hydrocynus vittatus marked using Hallmark model PDL plastic-tipped dart tags released into a 1 730 m2 pond at Kamutjonga Inland Fisheries Institute, Namibia, and inspected bi-monthly for the presence or absence of tags. No mortality was observed during the experiment. All marked fish had lost their tags after 10 months and 50% tag loss was estimated at 3.9 months. The high tag loss rate indicates that PDL plastic-tipped dart tags are not suitable for long-term studies on this species. 相似文献
86.
Respirometric assays at fixed and process temperatures to monitor composting process 总被引:8,自引:0,他引:8
Barrena Gómez R Vázquez Lima F Gordillo Bolasell MA Gea T Sánchez Ferrer A 《Bioresource technology》2005,96(10):1153-1159
A static respirometer was built to determine the respiration index (RI) of composting samples. Respiration indices of different sludges were determined at 37 degrees C (RI37) and at the in situ temperature of the composter at sampling (RI(T)). Results indicated that both indices correlated well with temperature evolution in the composter. RI(T) were more representative of the metabolic activity in the reactor and more sensitive to temperature and composition variations of the composting material, but could not indicate the stability of the material at later stages of the process. Moreover, significance of RI units was shown in the composting of a highly compostable residue. According to the stability limits suggested in the literature, initial RI expressed on dry matter (DM) basis corresponds to a stable material (RI < 1 mgO2gDM(-1)h(-1)) whereas initial RI expressed on organic matter basis (OM) corresponds to an unstable material (RI = 2.5 mgO2gOM(-1)h(-1)). 相似文献
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88.
Enhancement of Candida rugosa lipase production by using different control fed-batch operational strategies 总被引:2,自引:0,他引:2
Gordillo MA Sanz A Sánchez A Valero F Montesinos JL Lafuente J Solá C 《Biotechnology and bioengineering》1998,60(2):156-168
Simulation studies have predicted that maximum lipase activity is reached with fed-batch operation strategies. In this work, two different fed-batch operational strategies have been studied: constant substrate feeding rate and specific growth rate control. A constant substrate feeding rate strategy showed that maximum aqueous lipolytic activity (55 U/mL) was reached at low substrate feeding rates, whereas lipase tends to accumulate inside the cell at higher rates of substrate addition. In the second fed-batch strategy studied, a feedback control strategy has been developed based on the estimation of state variables (X and mu) from the measurement of indirect variables such as CER by means of mass spectrometry techniques. An on-off controller was then used to maintain the specific growth rate at the desired value by adjusting the substrate feeding rate. A constant specific growth rate strategy gave higher final levels of aqueous lipolytic activity (117 U/mL) at low specific growth rates. At higher specific growth rates the enzyme remained accumulated inside the cell, as was observed with a constant feeding fed-batch strategy. With a constant specific growth rate strategy, lipase production by Candida rugosa was enhanced 10-fold compared to a batch operation. Purification studies have demonstrated that lipolytic and esterasic specific activity ratios of Candida rugosa isoenzymes can be modified by using different operational conditions. These studies have also showed that the isoenzymes obtained in a controlled growth rate strategy are around three- to four-fold more active than those obtained in a constant feeding rate strategy. 相似文献
89.
Effects of light intensity, CO2 and nitrogen supply on lipid class composition of Dunaliella viridis
Francisco J. L. Gordillo Madeleine Goutx Felix L. Figueroa F. Xavier Niell 《Journal of applied phycology》1998,10(2):135-144
Lipid class composition of Dunaliella viridis Teodoresco was analysed using thin layer chromatography coupled with flame ionisation
detection (TLC/FID technique). D. viridis was cultured under four different photon fluence rates and in darkness, and under
two different conditions of CO2 supply (atmospheric and 1%) with and without nitrogen sufficiency. Nine lipid classes were identified and quantified. Total
lipids per cell and acetone-mobile polar lipids decreased with light, while the percentage of sterols and triglycerides increased
with increasing irradiance. Total phospholipids increase was related with growth rate while hydrocarbons, wax esters and sterol
esters accumulated in darkness. There were almost no changes in total lipids per cell because of nitrogen limitation; however,
nitrogen limitation led to higher changes in lipid class composition under 1% CO2 than under atmospheric CO2 levels. The main reserve lipid, triglycerides, accumulated in high amounts under 1% CO2 and nitrogen limitation, increasing from 1% to 22% of total lipids. The ratio sterols/acetone-mobile polar lipids could be
an index of the 'light status' independently of nitrogen limitation, while the ratio triglycerides/total phospholipids could
indicate any physiological stress uncoupling C and N metabolism and affecting the growth rate.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
90.
Asensio JL; Canada FJ; Bruix M; Gonzalez C; Khiar N; Rodriguez-Romero A; Jimenez-Barbero J 《Glycobiology》1998,8(6):569-577
The specific interaction of hevein with GlcNAc-containing oligosaccharides
has been analyzed by1H-NMR spectroscopy. The association constants for the
binding of hevein to a variety of ligands have been estimated from1H-NMR
titration experiments. The association constants increase in the order
GlcNAc-alpha(1-->6)-Man < GlcNAc < benzyl-beta-GlcNAc <
p-nitrophenyl-beta-GlcNAc < chitobiose < p-
nitrophenyl-beta-chitobioside < methyl-beta-chitobioside <
chitotriose. Entropy and enthalpy of binding for different complexes have
been obtained from van't Hoff analysis. The driving force for the binding
process is provided by a negative DeltaH0which is partially compensated by
negative DeltaS0. These negative signs indicate that hydrogen bonding and
van der Waals forces are the major interactions stabilizing the complex.
NOESY NMR experiments in water solution provided 475 accurate protein
proton-proton distance constraints after employing the MARDIGRAS program.
In addition, 15 unambiguous protein/carbohydrate NOEs were detected. All
the experimental constraints were used in a refinement protocol including
restrained molecular dynamics in order to determine the highly refined
solution conformation of this protein- carbohydrate complex. With regard to
the NMR structure of the free protein, no important changes in the protein
nOe's were observed, indicating that carbohydrate-induced conformational
changes are small. The average backbone rmsd of the 20 refined structures
was 0.055 nm, while the heavy atom rmsd was 0.116 nm. It can be deduced
that both hydrogen bonds and van der Waals contacts confer stability to the
complex. A comparison of the three-dimensional structure of hevein in
solution to those reported for wheat germ agglutinin (WGA) and hevein
itself in the solid state has also been performed. The polypeptide
conformation has also been compared to the NMR-derived structure of a
smaller antifungical peptide, Ac-AMP2.
相似文献