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991.
Gilles Lemesle Fleur Maury Olivia Beseme Lionel Ovart Philippe Amouyel Nicolas Lamblin Pascal de Groote Christophe Bauters Florence Pinet 《PloS one》2015,10(4)
Risk stratification of patients with systolic chronic heart failure (HF) is critical to better identify those who may benefit from invasive therapeutic strategies such as cardiac transplantation. Proteomics has been used to provide prognostic information in various diseases. Our aim was to investigate the potential value of plasma proteomic profiling for risk stratification in HF. A proteomic profiling using surface enhanced laser desorption ionization - time of flight - mass spectrometry was performed in a case/control discovery population of 198 patients with systolic HF (left ventricular ejection fraction <45%): 99 patients who died from cardiovascular cause within 3 years and 99 patients alive at 3 years. Proteomic scores predicting cardiovascular death were developed using 3 regression methods: support vector machine, sparse partial least square discriminant analysis, and lasso logistic regression. Forty two ion m/z peaks were differentially intense between cases and controls in the discovery population and were used to develop proteomic scores. In the validation population, score levels were higher in patients who subsequently died within 3 years. Similar areas under the curves (0.66 – 0.68) were observed for the 3 methods. After adjustment on confounders, proteomic scores remained significantly associated with cardiovascular mortality. Use of the proteomic scores allowed a significant improvement in discrimination of HF patients as determined by integrated discrimination improvement and net reclassification improvement indexes. In conclusion, proteomic analysis of plasma proteins may help to improve risk prediction in HF patients. 相似文献
992.
Clement Q. Fontenelle Zhong Wang Christine Fossey Thomas Cailly Bruno Linclau Frederic Fabis 《Bioorganic & medicinal chemistry》2013,21(23):7529-7538
Analogues of potent 5-HT4R antagonists possessing a fluorinated N-alkyl chain have been synthesized in order to investigate the effect of the resulting change in basicity and lipophilicity on the affinity and selectivity profile. We demonstrate that for this series, the affinity is decreased with decreased basicity of the piperidine’s nitrogen atom. In contrast, the resulting increase in lipophilicity has minimal impact on binding affinity and selectivity. 3,3,3-Trifluoropropyl and 4,4,4-trifluorobutyl derivatives 6d and 6e have shown to bind to the 5-HT4R while maintaining their pharmacological profile and selectivity toward other 5-HT receptors. 相似文献
993.
994.
Identification, developmental expression and tissue distribution of deaminoneuraminate hydrolase (KDNase) activity in rainbow trout 总被引:1,自引:1,他引:0
Angata Takashi; Kitajima Ken; Inoue Sadako; Chang Joseph; Warner Thomas G.; Troy Frederic A. II; Inoue Yasuo 《Glycobiology》1994,4(4):517-523
A deaminoneuraminosyl-glycohydrolase (KDNase), which catalysesthe hydrolysis of 相似文献
995.
Alessandra Teixeira Vidal Homero Nogueira Guimarães Danielle Cristiane Correa de Paula Frederic Frezard Neila Márcia Silva-Barcellos Andrea Grabe-Guimarães 《Life sciences》2010,86(1-2):17-23
AimsThe purpose of the present work was to investigate the ability of pyridostigmine encapsulated in long-circulating liposomes, to protect against ECG (electrocardiogram) alterations induced by sympathetic stimulation in rats.Main methodsThe encapsulation of pyridostigmine was carried out by freeze–thaw and extrusion. Blood pressure and ECG (limb lead II) were monitored in anaesthetized male Wistar rats. The formulation containing pyridostigmine was intravenously administrated in 0.1, 0.3 and 1.0 mg/kg doses, and sympathetic stimulation was conducted by administration of 1 or 3 μg of noradrenaline (NA) after 1, 2, 4 or 6 h. The obtained cardiovascular parameters were compared to animals that received intravenous injection of pyridostigmine in free form or saline.Key findingsAfter saline, NA induced a significant increase in QT interval (22.3% after 3.0 μg). Previous administration of free pyridostigmine significantly prevented the increase of QT interval after sympathetic stimulation and the most prominent effect was observed after 1 h for the dose of 0.3 mg/kg (6.8% after 3.0 μg of NA) and was no longer observed after 2 h of the treatment. On the other hand, the maximum effect of pyridostigmine in liposomal formulation preventing QT interval increase was observed 2 h after treatment (9.7% after 3.0 μg of NA) and was still present until 6 h when 1 mg/kg was previous administrated.SignificanceThe results of the present study, beyond to confirm the cardioprotective action of pyridostigmine, suggest that liposomal pyridostigmine may be a potential therapeutic alternative to prevent cardiovascular disturbances resulting from sympathetic hyperactivity. 相似文献
996.
997.
998.
Guillermo Quijano Maria Hernandez Santiago Villaverde Frederic Thalasso Raul Muñoz 《Applied microbiology and biotechnology》2010,85(3):543-551
Silicone oil 20 and 200 cSt, a perfluorocarbon (FC40TM), heptamethylnonane, Kraton, Elvax, and Desmopan were evaluated for
their ability to enhance oxygen transfer in stirred tank and airlift reactors (STR and ALR, respectively). None of the vectors
tested was either toxic or biodegradable and they exhibited a moderate affinity for oxygen (gas/vector partitioning coefficients
K\textg/\textv = C\textg ·C\textv- 1 K_{{{\text{g}}/{\text{v}}}} = C_{\text{g}} \cdot C_{\text{v}}^{- 1} ranging from 3 to 5.1). FC40 was highly volatile, while KratonTM and ElvaxTM exhibited a low thermal stability, which constitutes
a serious handicap for their implementation in fermentations. Silicone oil 20 cSt and Desmopan supported the highest oxygen
transfer rates under abiotic conditions in both STR and ALR designs, with enhancement factors of up to 90% and 250%, respectively,
compared to control tests (deprived of vector). The fact that these vectors showed the highest K
g/v proved that, besides the classical selection criteria, the in situ hydrodynamic behavior (which affects K
L
a) must be considered for vector selection. The use of silicone oil 20 cSt and Desmopan in glucose-supplemented Saccharomyces cerevisiae fermentations resulted in a two- and threefold increase in biomass productions, respectively. The better performance of Desmopan
in terms of biomass growth enhancement, together with the absence of the operational problems inherent to the use of liquid
vectors (such as intensive foaming, high cost, and difficult solvent recovery), make solid vectors a promising and cost-effective
alternative in the future developments of two-phase partitioning bioreactors. 相似文献
999.
We study numerically the local dynamics of the intracellular calcium concentration in the vicinity of a voltage- and calcium-dependent
plasma membrane L-type calcium channel. To account for the low number of Ca2+ ions and buffer molecules present in sub-femtoliter volumes, we use an exact stochastic simulation algorithm including diffusion.
We present a novel, unified simulation method that implements reaction-diffusion events of Ca2+ ions and buffer molecules, stochastic ion channel gating and channel conductance as a multivariate Markov process. For fixed-voltage
dynamics, e.g. under voltage-clamp conditions, it is shown that voltage-sensitive channel-gating steps can be incorporated
exactly. We compare multi- and single-voxel geometries and show that the single-voxel approach leads to almost identical first-
and second-order moments, at much lower computation time. Numerical examples illustrate the variability in local Ca2+ fluctuations as induced by bursts of channel openings in response to membrane depolarisations. Finally, by introducing calmodulin
as a link, it is shown how this variability is passed on to downstream signalling pathways. The method may prove useful to
study calcium microdomains and calcium-regulated processes triggered by membrane depolarisations as evoked by, e.g., viral
channel-forming proteins during virus-host cell interactions. 相似文献
1000.
Isabelle Hippolyte Frederic Bakry Marc Seguin Laetitia Gardes Ronan Rivallan Ange-Marie Risterucci Christophe Jenny Xavier Perrier Françoise Carreel Xavier Argout Pietro Piffanelli Imtiaz A Khan Robert NG Miller Georgios J Pappas Didier Mbéguié-A-Mbéguié Takashi Matsumoto Veronique De Bernardinis Eric Huttner Andrzej Kilian Franc-Christophe Baurens Angélique D'Hont François Cote Brigitte Courtois Jean-Christophe Glaszmann 《BMC plant biology》2010,10(1):1-18