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81.
Salvador?Peiru Andres?Aguirre Florencia?Eberhardt Mauricio?Braia Rodolfo?Cabrera Hugo?G.?MenzellaEmail author 《Biotechnology for biofuels》2015,8(1):223
Background
Biodiesels produced from transesterification of vegetable oils have a major quality problem due to the presence of precipitates, which need to be removed to avoid clogging of filters and engine failures. These precipitates have been reported to be mostly composed of steryl glucosides (SGs), but so far industrial cost-effective methods to remove these compounds are not available. Here we describe a novel method for the efficient removal of SGs from biodiesel, based on the hydrolytic activity of a thermostable β-glycosidase obtained from Thermococcus litoralis.Results
A steryl glucosidase (SGase) enzyme from T. litoralis was produced and purified from Escherichia coli cultures expressing a synthetic gene, and used to treat soybean-derived biodiesel. Several optimization steps allowed for the selection of optimal reaction conditions to finally provide a simple and efficient process for the removal of SGs from crude biodiesel. The resulting biodiesel displayed filterability properties similar to distilled biodiesel according to the total contamination (TC), the cold soak filtration test (CSFT), filter blocking tendency (FBT), and cold soak filter blocking tendency (CSFBT) tests. The process was successfully scaled up to a 20 ton reactor, confirming its adaptability to industrial settings.Conclusions
The results presented in this work provide a novel path for the removal of steryl glucosides from biodiesel using a cost-effective, environmentally friendly and scalable enzymatic process, contributing to the adoption of this renewable fuel.82.
Raimon Sabate Frederic Rousseau Joost Schymkowitz Salvador Ventura 《PLoS computational biology》2015,11(1)
Typical amyloid diseases such as Alzheimer''s and Parkinson''s were thought to exclusively result from de novo aggregation, but recently it was shown that amyloids formed in one cell can cross-seed aggregation in other cells, following a prion-like mechanism. Despite the large experimental effort devoted to understanding the phenomenon of prion transmissibility, it is still poorly understood how this property is encoded in the primary sequence. In many cases, prion structural conversion is driven by the presence of relatively large glutamine/asparagine (Q/N) enriched segments. Several studies suggest that it is the amino acid composition of these regions rather than their specific sequence that accounts for their priogenicity. However, our analysis indicates that it is instead the presence and potency of specific short amyloid-prone sequences that occur within intrinsically disordered Q/N-rich regions that determine their prion behaviour, modulated by the structural and compositional context. This provides a basis for the accurate identification and evaluation of prion candidate sequences in proteomes in the context of a unified framework for amyloid formation and prion propagation. 相似文献
83.
Victoria Catalán Javier Gómez-Ambrosi Amaia Rodríguez Beatriz Ramírez Víctor Valentí Rafael Moncada Camilo Silva Javier Salvador Gema Frühbeck 《Genes & nutrition》2015,10(3)
Inflammation is a critical contributor to the pathogenesis of metabolic disorders with adipose tissue being crucial in the inflammatory response by releasing multiple adipokines with either pro- or anti-inflammatory activities with potential functions as metabolic regulators. Peripheral blood mononuclear cells (PBMC) have been proposed as representative of the inflammatory status in obesity. The aim of the present study was to evaluate the contribution of PBMC to the obesity-associated chronic inflammation analyzing the expression of novel adipokines. Samples obtained from 69 subjects were used in the study. Real-time PCR determinations were performed to quantify gene expression levels in PBMC of novel adipokines including chemerin, chitinase-3-like protein 1 (YKL-40), lipocalin-2 (LCN-2) and osteopontin (OPN), and their circulating concentrations were also determined by ELISA. We show, for the first time, that PBMC gene expression levels of chemerin (P < 0.0001), chitinase-3-like protein 1 (P = 0.010), lipocalin-2 (P < 0.0001) and osteopontin (P < 0.0001) were strongly upregulated in obesity independently of the glycemic state. Circulating concentrations of these adipokines followed the same trend being significantly higher (P < 0.05) in obese normoglycemic and type 2 diabetic patients compared to lean volunteers and also associated (P < 0.05) with their corresponding mRNA levels in PBMC. These results provide evidence that alterations in inflammation-related adipokines are manifest in PBMC, which might contribute to the low-grade chronic inflammation that characterizes obesity.
Electronic supplementary material
The online version of this article (doi:10.1007/s12263-015-0460-8) contains supplementary material, which is available to authorized users. 相似文献84.
Gerard H. Bode Karin E. Pickl Maria Sanchez-Purrà Berta Albaiges Salvador Borrós Andy J. G. P?tgens Christoph Schmitz Frank M. Sinner Mario Losen Harry W. M. Steinbusch Hans-Georg Frank Pilar Martinez-Martinez European NanoBioPharmaceutics Research Initiative 《PloS one》2015,10(5)
AimsThe aim of the current study was to develop a method to detect peptide-linked nanoparticles in blood plasma.ResultsThe ELISA based method for the detection of FITC labeled peptides had a detection limit of 1 ng/mL. We were able to accurately measure peptides bound to pentafluorophenyl methacrylate nanoparticles in blood plasma of rats, and similar results were obtained by LC/MS.ConclusionsWe detected FITC-labeled peptides on pentafluorophenyl methacrylate nanoparticles after injection in vivo. This method can be extended to detect nanoparticles with different chemical compositions. 相似文献
85.
86.
Torregrosa-Hetland CJ Villanueva J López-Font I Garcia-Martinez V Gil A Gonzalez-Vélez V Segura J Viniegra S Gutiérrez LM 《Cellular and molecular neurobiology》2010,30(8):1315-1319
In chromaffin cells, SNARE proteins, forming the basic exocytotic machinery are present in membrane clusters of 500–600 nm
in diameter. These microdomains containing both SNAP-25 and syntaxin-1 are dynamic and the expression of altered forms of
SNAREs modifies not only their motion but also the mobility of the associated granules. It is also clear that SNARE microdomain
location defines the place for individual vesicle fusion and that the alteration of cluster dynamics affects the fusion process
itself. Interestingly, these SNARE patches colocalize with the borders of F-actin cages forming the cytoskeletal cortical
network, and these borders also contain clusters of L- and P/Q type calcium channels. The organization of the secretory machinery
in association with the borders of cytoskeletal cages seems to be an effective way to promote fast coupling between calcium
entry and catecholamine release as demonstrated with the use of mathematical secretory models. 相似文献
87.
Fischer H Lutay N Ragnarsdóttir B Yadav M Jönsson K Urbano A Al Hadad A Rämisch S Storm P Dobrindt U Salvador E Karpman D Jodal U Svanborg C 《PLoS pathogens》2010,6(9):e1001109
The mucosal immune system identifies and fights invading pathogens, while allowing non-pathogenic organisms to persist. Mechanisms of pathogen/non-pathogen discrimination are poorly understood, as is the contribution of human genetic variation in disease susceptibility. We describe here a new, IRF3-dependent signaling pathway that is critical for distinguishing pathogens from normal flora at the mucosal barrier. Following uropathogenic E. coli infection, Irf3(-/-) mice showed a pathogen-specific increase in acute mortality, bacterial burden, abscess formation and renal damage compared to wild type mice. TLR4 signaling was initiated after ceramide release from glycosphingolipid receptors, through TRAM, CREB, Fos and Jun phosphorylation and p38 MAPK-dependent mechanisms, resulting in nuclear translocation of IRF3 and activation of IRF3/IFNβ-dependent antibacterial effector mechanisms. This TLR4/IRF3 pathway of pathogen discrimination was activated by ceramide and by P-fimbriated E. coli, which use ceramide-anchored glycosphingolipid receptors. Relevance of this pathway for human disease was supported by polymorphic IRF3 promoter sequences, differing between children with severe, symptomatic kidney infection and children who were asymptomatic bacterial carriers. IRF3 promoter activity was reduced by the disease-associated genotype, consistent with the pathology in Irf3(-/-) mice. Host susceptibility to common infections like UTI may thus be strongly influenced by single gene modifications affecting the innate immune response. 相似文献
88.
Armand Salvador Mijares Florent Détroit Rainer Grün Maxime Aubert Nida Cuevas Eusebio Dizon 《Journal of human evolution》2010,59(1):123-132
Documentation of early human migrations through Island Southeast Asia and Wallacea en route to Australia has always been problematic due to a lack of well-dated human skeletal remains. The best known modern humans are from Niah Cave in Borneo (40-42 ka), and from Tabon Cave on the island of Palawan, southwest Philippines (47 ± 11 ka). The discovery of Homo floresiensis on the island of Flores in eastern Indonesia has also highlighted the possibilities of identifying new hominin species on islands in the region. Here, we report the discovery of a human third metatarsal from Callao Cave in northern Luzon. Direct dating of the specimen using U-series ablation has provided a minimum age estimate of 66.7 ± 1 ka, making it the oldest known human fossil in the Philippines. Its morphological features, as well as size and shape characteristics, indicate that the Callao metatarsal definitely belongs to the genus Homo. Morphometric analysis of the Callao metatarsal indicates that it has a gracile structure, close to that observed in other small-bodied Homo sapiens. Interestingly, the Callao metatarsal also falls within the morphological and size ranges of Homo habilis and H. floresiensis. Identifying whether the metatarsal represents the earliest record of H. sapiens so far recorded anywhere east of Wallace’s Line requires further archaeological research, but its presence on the isolated island of Luzon over 65,000 years ago further demonstrates the abilities of humans to make open ocean crossings in the Late Pleistocene. 相似文献
89.
David M. Alba Salvador Moyà‐Solà Assumpció Malgosa Isaac Casanovas‐Vilar Josep M. Robles Sergio Almécija Jordi Galindo Cheyenn Rotgers Juan Vicente Bertó Mengual 《American journal of physical anthropology》2010,141(1):52-75
Pliopithecus (Pliopithecus) canmatensis sp. nov. is described from several Late Aragonian localities from Abocador de Can Mata (ACM) in els Hostalets de Pierola (Vallès‐Penedès Basin, Catalonia, Spain), spanning from ~11.7 to 11.6 Ma (C5r.3r subchron), and being correlated to the MN8 (reference locality La Grive L3). The ACM remains display a pliopithecine dental morphology with well‐developed pliopithecine triangles on M/2 and M/3. This, together with other occlusal details, negates an attribution to the subgenus Epipliopithecus. Although slightly smaller, the ACM remains are most similar in size to comparable elements of P. piveteaui and P. antiquus. Several occlusal details (such as the greater development of the buccal cingulid in lower molars) and dental proportions (M/3 much longer than M/2), however, indicate greater similarities with P. antiquus from Sansan and La Grive. The ACM remains, however, differ from P. antiquus in dental proportions as well as occlusal morphology of the lower molars (including the less peripheral position of the protoconid and more medial position of the hypoconulid, the more mesial position of the buccal cuspids as compared to the lingual ones, the narrower but distinct mesial fovea, the higher trigonid, and the more extensive buccal cingulid, among others). These differences justify a taxonomic distinction at the species level of the ACM pliopithecid remains with respect to P. antiquus. Previous pliopithecid findings from the Vallès‐Penedès Basin, previously attributed to P. antiquus, are neither attributable to the latter species nor to the newly erected one. Am J Phys Anthropol, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
90.