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41.
Teresa Auguet Alba Berlanga Esther Guiu-Jurado Salomé Martinez José Antonio Porras Gemma Aragonès Fátima Sabench Mercé Hernandez Carmen Aguilar Joan Josep Sirvent Daniel Del Castillo Cristóbal Richart 《International journal of molecular sciences》2014,15(12):22173-22187
Lipid accumulation in the human liver seems to be a crucial mechanism in the pathogenesis and the progression of non-alcoholic fatty liver disease (NAFLD). We aimed to evaluate gene expression of different fatty acid (FA) metabolism-related genes in morbidly obese (MO) women with NAFLD. Liver expression of key genes related to de novo FA synthesis (LXRα, SREBP1c, ACC1, FAS), FA uptake and transport (PPARγ, CD36, FABP4), FA oxidation (PPARα), and inflammation (IL6, TNFα, CRP, PPARδ) were assessed by RT-qPCR in 127 MO women with normal liver histology (NL, n = 13), simple steatosis (SS, n = 47) and non-alcoholic steatohepatitis (NASH, n = 67). Liver FAS mRNA expression was significantly higher in MO NAFLD women with both SS and NASH compared to those with NL (p = 0.003, p = 0.010, respectively). Hepatic IL6 and TNFα mRNA expression was higher in NASH than in SS subjects (p = 0.033, p = 0.050, respectively). Interestingly, LXRα, ACC1 and FAS expression had an inverse relation with the grade of steatosis. These results were confirmed by western blot analysis. In conclusion, our results indicate that lipogenesis seems to be downregulated in advanced stages of SS, suggesting that, in this type of extreme obesity, the deregulation of the lipogenic pathway might be associated with the severity of steatosis. 相似文献
42.
Thermophiles as Potential Source of Novel Endotoxin Antagonists: the Full Structure and Bioactivity of theLipo‐oligosaccharide from Thermomonas hydrothermalis
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Dr. Flaviana Di Lorenzo Dr. Ida Paciello Dr. Luigi Lembo Fazio Dr. Luciana Albuquerque Dr. Luisa Sturiale Prof. Milton S. da Costa Prof. Rosa Lanzetta Prof. Michelangelo Parrilli Prof. Domenico Garozzo Prof. Maria Lina Bernardini Dott. Alba Silipo Prof. Antonio Molinaro 《Chembiochem : a European journal of chemical biology》2014,15(14):2146-2155
Thermomonas hydrothermalis is a Gram‐negative thermophilic bacterium that is able to live at 50 °C. This ability is attributed to chemical modifications, involving those to bacterial cell‐wall components, such as proteins and (glyco)lipids. As the main component of the outer membrane of Gram‐negative bacteria, lipopolysaccharides (LPSs) are exposed to the environment, thus they can undergo structural chemical changes to allow thermophilic bacteria to live at their optimal growth temperature. Furthermore, as one of the major target of the eukaryotic innate immune system, LPS elicits host immune response in a structure‐dependent mode; thus the uncommon chemical features of thermophilic bacterial LPSs might exert a different biological action on the innate immune system—an antagonistic effect, as shown in studies of LPS structure–activity relationship in the ongoing research into antagonist LPS candidates. Here, we report the complete structural and biological activity analysis of the lipo‐oligosaccharide isolated from Thermomonas hydrothermalis, achieved by a multidisciplinary approach (chemical analysis, NMR, MALDI MS and cellular immunology). We demonstrate a tricky and interesting structure combined with a very interesting effect on human innate immunity. 相似文献
43.
Scott Spangler Chen Ying Jeffrey Kreulen Stephen Boyer Thomas Griffin Alfredo Alba Linda Kato Ana Lelescu Su YanAuthor vitae 《World Patent Information》2011,33(4):328-339
Exploratory Analytics is the process of analyzing data for the purpose of forming hypotheses. Patent data sets, because they are relatively large and diverse and because they consist of a mixture of structured and unstructured information present a formidable challenge and a great opportunity in applying exploratory analytics techniques. In this paper we describe methods we have implemented for effective exploratory analytics on patent data sets using an interactive approach and a web based software tool called SIMPLE. We use real-world case studies to demonstrate the effectiveness of our exploratory analytics approach in the discovery of useful information from the patent corpus. 相似文献
44.
R. Velazquez-Hernandez I. Rojas-Rodriguez J. Carmona-Rodríguez S. Jiménez-Sandoval M. E. Rodriguez-Garcia 《International Journal of Thermophysics》2011,32(3):720-728
In this research quaternary alloy thin films made of Cu, CdTe, and O have been grown and characterized. The samples used in
this investigation were grown simultaneously by reactive RF co-sputtering and by introducing oxygen and argon in the chamber
during growth and changing the power in the Cu target from 10 W to 50 W. The carrier distribution as a function of the position
was studied by using energy dispersive spectroscopy–scanning electronic microscopy (EDS–SEM), micro-Raman spectroscopy, and
photocarrier images. Structural characterization was carried out by using X-ray diffraction. According to the results, a lateral
carrier distribution was found in all samples and a new phase identified as Cu2Te was revealed for samples grown at 50 W. 相似文献
45.
Assessment of the metal pollution, potential toxicity and speciation of sediment from Algeciras Bay (South of Spain) using chemometric tools 总被引:5,自引:0,他引:5
Díaz-de Alba M Galindo-Riaño MD Casanueva-Marenco MJ García-Vargas M Kosore CM 《Journal of hazardous materials》2011,190(1-3):177-187
A study to determine total and mobile heavy metals concentrations in sediments from Algeciras Bay was performed and pollution hotspots were identified. The effects on aquatic organisms were established using sediment quality guidelines (SQGs). Ni and Cr exceeded the effect range medium and low levels, respectively, around industrial area. Potential toxicity of metals was determined by diethylenetriaminepenta-acetic acid (DTPA) extractions and low alert levels of Co, Cu, Zn, Cd, Ni and Pb were exceeded at most sampling sites. Three pollution indicators were used showing significant values for As, Ni, Cr, Pb and Cd. Sediment speciation using the sequential extraction BCR procedure was carried out, being Cd, Zn, Pb and As the most available metals. Principal component, cluster and ANOVA analyses were performed in order to assess the sources of metals and the influence of seasonality and anthropogenic activities on the sediment quality. Two principal component analysis (PCA) factors were obtained identifying the sampling sites affected by anthropogenic activities; Ni-Cr and Zn-Cu-V clusters were also obtained associated with stainless steel and petrochemical industrial activities. ANOVA showed the outstanding sites because of total metal concentration and significant differences among sampling sites by the acid extractable and reducible fractions for all metals except for Ba and V. 相似文献
46.
Rodriguez-Garcia G Molinos-Senante M Hospido A Hernández-Sancho F Moreira MT Feijoo G 《Water research》2011,45(18):5997-6010
The objective of wastewater treatment plants (WWTPs) is to prevent pollution. However, it is necessary to assess their sustainability in order to ensure that pollution is being removed, not displaced. In this research, the performance of 24 WWTPs has been evaluated using a streamlined Life Cycle Assessment (LCA) with Eutrophication Potential (EP) and Global Warming Potential (GWP) as environmental indicators, and operational costs as economic indicators. WWTPs were further classified in six typologies by their quality requirements according to their final discharge point or water reuse. Moreover, two different functional units (FU), one based on volume (m3) and the other on eutrophication reduction (kg PO43− removed) were used to further determine sustainability. A correlation between legal requirements and technologies used to achieve them was found: Organic matter removal plants were found to be less costly both in environmental and economic terms if volume was used as the functional unit, while more demanding typologies such as reuse plants showed a trade-off between lower EP and higher cost and GWP; however, this is overcome if the second FU is used instead, proving the sustainability of these options and that this FU better reflects the objectives of a WWTP. 相似文献
47.
Ince Laurence P.; Greene Renee Y.; Alba Augusta; Zaretsky Herbert H. 《Canadian Metallurgical Quarterly》1987,6(2):173
Treated 30 individuals (aged 24–82 yrs) with subjective tinnitus aurium with a matching-to-sample feedback procedure. Ss' tinnitus sounds were reproduced audiometrically on all characteristics and were presented to them in the noninvolved ear or in both ears when the tinnitus was binaural. This experimental sound was then reduced in 5-db steps within sessions, and Ss had the task of concentrating on reducing the loudness of their tinnitus until a match was achieved between it and the experimental sound at each new db level. Results show a significant difference in db levels from baseline to final training session. Nearly all Ss demonstrated a marked reduction in tinnitus loudness, with several eliminating it completely. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
R Ferrero Doria P Guzmán Valls J López Alba M Tomás Ros JL Rico Galiano LO Fontana Compiano 《Canadian Metallurgical Quarterly》1996,20(4):380-383
SETTING: A voluntary community health worker programme, in the Western Cape, South Africa, utilizing volunteers to administer directly observed therapy to tuberculosis (TB) patients. OBJECTIVE: This study describes the perceptions of health team members regarding the voluntary community health worker project. DESIGN: A qualitative, participatory research study utilizing focus groups. RESULTS: TB was perceived by the health team to be a stigmatized disease causing some patients to be reluctant to be associated with the TB control programme. Despite the project's dedicated approach to case-holding, volunteers expressed the need to develop skills in providing more comprehensive care. The volunteers appear to administer a more personalized service to TB patients and can bridge the gap between TB patients and the health agency. CONCLUSION: Sustained evaluation and support seem to be a vital tool in integrating a volunteer project into a health team approach. Its effectiveness appears to depend to a large degree on the people involved. 相似文献
49.
Antonio J. Nebro Enrique Alba Francisco Luna 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2007,11(6):531-540
This paper analyzes some technical and practical issues concerning the use of parallel systems to solve multi-objective optimization
problems using enumerative search. This technique constitutes a conceptually simple search strategy, and it is based on evaluating
each possible solution from a given finite search space. The results obtained by enumeration are impractical for most computer
platforms and researchers, but they exhibit a great interest because they can be used to be compared against the values obtained
by stochastic techniques. We analyze here the use of a grid computing system to cope with the limits of enumerative search.
After evaluating the performance of the sequential algorithm, we present, first, a parallel algorithm targeted to multiprocessor
systems. Then, we design a distributed version prepared to be executed on a federation of geographically distributed computers
known as a computational grid. Our conclusion is that this kind of systems can provide to the community with a large and precise set of Pareto fronts that
would be otherwise unknown. 相似文献
50.
Giacobini M. Tomassini M. Tettamanzi A.G.B. Alba E. 《Evolutionary Computation, IEEE Transactions on》2005,9(5):489-505
In this paper, we present quantitative models for the selection pressure of cellular evolutionary algorithms on regular one- and two-dimensional (2-D) lattices. We derive models based on probabilistic difference equations for synchronous and several asynchronous cell update policies. The models are validated using two customary selection methods: binary tournament and linear ranking. Theoretical results are in agreement with experimental values, showing that the selection intensity can be controlled by using different update methods. It is also seen that the usual logistic approximation breaks down for low-dimensional lattices and should be replaced by a polynomial approximation. The dependence of the models on the neighborhood radius is studied for both topologies. We also derive results for 2-D lattices with variable grid axes ratio. 相似文献