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991.
Susana C. Arcos Sergio Ciordia Lee Roberston Inés Zapico Yolanda Jiménez‐Ruiz Miguel Gonzalez‐Muñoz Ignacio Moneo Noelia Carballeda‐Sangiao Ana Rodriguez‐Mahillo Alfonso Navas 《Proteomics》2014,14(12):1547-1568
The parasite species complex Anisakis simplex sensu lato (Anisakis simplex sensu stricto; (A. simplex s.s.), A. pegreffii, A. simplex C) is the main cause of severe anisakiasis (allergy) worldwide and is now an important health matter. In this study, the relationship of this Anisakis species complex and their allergenic capacities is assessed by studying the differences between the two most frequent species (A. simplex s.s., A. pegreffii) and their hybrid haplotype by studying active L3 larvae parasiting Merluccius merluccius. They were compared by 2D gel electrophoresis and parallel Western blot (2DE gels were hybridized with pools of sera from Anisakis allergenic patients). Unambiguous spot differences were detected and protein assignation was made by MALDI‐TOF/TOF analysis or de novo sequencing. Seventy‐five gel spots were detected and the corresponding proteins were identified. Differentially expressed proteins for A. simplex s.s., A. pegreffii, and their hybrid are described and results are statistically supported. Twenty‐eight different allergenic proteins are classified according to different families belonging to different biological functions. These proteins are described for the first time as antigenic and potentially new allergens in Anisakis. Comparative proteomic analyses of allergenic capacities are useful for diagnosis, epidemiological surveys, and clinical research. All MS data have been deposited in the ProteomeXchange with identifier PXD000662 ( http://proteomecentral.proteomexchange.org/dataset/PXD000662 ). 相似文献
992.
Andrés Andrade-Domínguez Emmanuel Salazar María del Carmen Vargas-Lagunas Roberto Kolter Sergio Encarnación 《The ISME journal》2014,8(5):1041-1054
In the biosphere, many species live in close proximity and can thus interact in many different ways. Such interactions are dynamic and fall along a continuum between antagonism and cooperation. Because interspecies interactions are the key to understanding biological communities, it is important to know how species interactions arise and evolve. Here, we show that the feedback between ecological and evolutionary processes has a fundamental role in the emergence and dynamics of species interaction. Using a two-species artificial community, we demonstrate that ecological processes and rapid evolution interact to influence the dynamics of the symbiosis between a eukaryote (Saccharomyces cerevisiae) and a bacterium (Rhizobium etli). The simplicity of our experimental design enables an explicit statement of causality. The niche-constructing activities of the fungus were the key ecological process: it allowed the establishment of a commensal relationship that switched to ammensalism and provided the selective conditions necessary for the adaptive evolution of the bacteria. In this latter state, the bacterial population radiates into more than five genotypes that vary with respect to nutrient transport, metabolic strategies and global regulation. Evolutionary diversification of the bacterial populations has strong effects on the community; the nature of interaction subsequently switches from ammensalism to antagonism where bacteria promote yeast extinction. Our results demonstrate the importance of the evolution-to-ecology pathway in the persistence of interactions and the stability of communities. Thus, eco-evolutionary dynamics have the potential to transform the structure and functioning of ecosystems. Our results suggest that these dynamics should be considered to improve our understanding of beneficial and detrimental host–microbe interactions. 相似文献
993.
Valeriano Parravicini Sébastien Villéger Tim R. McClanahan Jesus Ernesto Arias‐González David R. Bellwood Jonathan Belmaker Pascale Chabanet Sergio R. Floeter Alan M. Friedlander François Guilhaumon Laurent Vigliola David Mouillot 《Ecology letters》2014,17(9):1101-1110
The impact of anthropogenic activity on ecosystems has highlighted the need to move beyond the biogeographical delineation of species richness patterns to understanding the vulnerability of species assemblages, including the functional components that are linked to the processes they support. We developed a decision theory framework to quantitatively assess the global taxonomic and functional vulnerability of fish assemblages on tropical reefs using a combination of sensitivity to species loss, exposure to threats and extent of protection. Fish assemblages with high taxonomic and functional sensitivity are often exposed to threats but are largely missed by the global network of marine protected areas. We found that areas of high species richness spatially mismatch areas of high taxonomic and functional vulnerability. Nevertheless, there is strong spatial match between taxonomic and functional vulnerabilities suggesting a potential win–win conservation‐ecosystem service strategy if more protection is set in these locations. 相似文献
994.
Xoaquín Moreira Kailen A. Mooney Sergio Rasmann William K. Petry Amparo Carrillo‐Gavilán Rafael Zas Luis Sampedro 《Ecology letters》2014,17(5):537-546
There is increasing evidence that geographic and climatic clines drive the patterns of plant defence allocation and defensive strategies. We quantified early growth rate and both constitutive and inducible chemical defences of 18 Pinaceae species in a common greenhouse environment and assessed their defensive allocation with respect to each species' range across climatic gradients spanning 31o latitude and 2300 m elevation. Constitutive defences traded‐off with induced defences, and these defensive strategies were associated with growth rate such that slow‐growing species invested more in constitutive defence, whereas fast‐growing species invested more in inducible defence. The position of each pine species along this trade‐off axis was in turn associated with geography; moving poleward and to higher elevations, growth rate and inducible defences decreased, while constitutive defence increased. These geographic patterns in plant defence were most strongly associated with variation in temperature. Climatic and geographical clines thus act as drivers of defence profiles by mediating the constraints imposed by trade‐offs, and this dynamic underlays global patterns of defence allocation. 相似文献
995.
Gloria Luz Paniagua-Contreras Eric Monroy-Pérez Felipe Vaca-Paniagua José Raymundo Rodríguez-Moctezuma Erasmo Negrete-Abascal Sergio Vaca 《Annals of clinical microbiology and antimicrobials》2014,13(1):1-9
Background
Methicillin-resistant Staphylococcus aureus (MRSA) are clinically relevant pathogens that cause severe catheter-related nosocomial infections driven by several virulence factors.Methods
We implemented a novel model of infection in vitro of reconstituted human epithelium (RHE) to analyze the expression patterns of virulence genes in 21 MRSA strains isolated from catheter-related infections in Mexican patients undergoing haemodialysis. We also determined the phenotypic and genotypic co-occurrence of antibiotic- and disinfectant-resistance traits in the S. aureus strains, which were also analysed by pulsed-field-gel electrophoresis (PFGE).Results
In this study, MRSA strains isolated from haemodialysis catheter-related infections expressed virulence markers that mediate adhesion to, and invasion of, RHE. The most frequent pattern of expression (present in 47.6% of the strains) was as follows: fnbA, fnbB, spa, clfA, clfB, cna, bbp, ebps, eap, sdrC, sdrD, sdrE, efb, icaA, and agr. Seventy-one percent of the strains harboured the antibiotic- and disinfectant-resistance genes ermA, ermB, tet(M), tet(K), blaZ, qacA, qacB, and qacC. PFGE of the isolated MRSA revealed three identical strains and two pairs of identical strains. The strains with identical PFGE patterns showed the same phenotypes and genotypes, including the same spa type (t895), suggesting hospital personnel manipulating the haemodialysis equipment could be the source of catheter contamination.Conclusion
These findings help define the prevalence of MRSA virulence factors in catheter-related infections. Some of the products of the expressed genes that we detected in this work may serve as potential antigens for inclusion in a vaccine for the prevention of MRSA-catheter-related infections. 相似文献996.
Tomás?Gutiérrez Valentina?Parra Rodrigo?Troncoso Christian?Pennanen Ariel?Contreras-Ferrat César?Vasquez-Trincado Pablo?E?Morales Camila?Lopez-Crisosto Cristian?Sotomayor-Flores Mario?Chiong Beverly?A?Rothermel Sergio?LavanderoEmail author 《Cell communication and signaling : CCS》2014,12(1):68
Background
Cardiac hypertrophy is characterized by alterations in both cardiac bioenergetics and insulin sensitivity. Insulin promotes glucose uptake by cardiomyocytes and its use as a substrate for glycolysis and mitochondrial oxidation in order to maintain the high cardiac energy demands. Insulin stimulates Ca2+ release from the endoplasmic reticulum, however, how this translates to changes in mitochondrial metabolism in either healthy or hypertrophic cardiomyocytes is not fully understood.Results
In the present study we investigated insulin-dependent mitochondrial Ca2+ signaling in normal and norepinephrine or insulin like growth factor-1-induced hypertrophic cardiomyocytes. Using mitochondrion-selective Ca2+-fluorescent probes we showed that insulin increases mitochondrial Ca2+ levels. This signal was inhibited by the pharmacological blockade of either the inositol 1,4,5-triphosphate receptor or the mitochondrial Ca2+ uniporter, as well as by siRNA-dependent mitochondrial Ca2+ uniporter knockdown. Norepinephrine-stimulated cardiomyocytes showed a significant decrease in endoplasmic reticulum-mitochondrial contacts compared to either control or insulin like growth factor-1-stimulated cells. This resulted in a reduction in mitochondrial Ca2+ uptake, Akt activation, glucose uptake and oxygen consumption in response to insulin. Blocking mitochondrial Ca2+ uptake was sufficient to mimic the effect of norepinephrine-induced cardiomyocyte hypertrophy on insulin signaling.Conclusions
Mitochondrial Ca2+ uptake is a key event in insulin signaling and metabolism in cardiomyocytes.997.
Juan Suárez Patricia Rivera Sergio Arrabal Ana Crespillo Antonia Serrano Elena Baixeras Francisco J. Pavón Manuel Cifuentes Rubén Nogueiras Joan Ballesteros Carlos Dieguez Fernando Rodríguez de Fonseca 《Disease models & mechanisms》2014,7(1):129-141
β-adrenergic receptor activation promotes brown adipose tissue (BAT) β-oxidation and thermogenesis by burning fatty acids during uncoupling respiration. Oleoylethanolamide (OEA) can inhibit feeding and stimulate lipolysis by activating peroxisome proliferator-activating receptor-α (PPARα) in white adipose tissue (WAT). Here we explore whether PPARα activation potentiates the effect of β3-adrenergic stimulation on energy balance mediated by the respective agonists OEA and . The effect of this pharmacological association on feeding, thermogenesis, β-oxidation, and lipid and cholesterol metabolism in epididymal (e)WAT was monitored. CL316243 (1 mg/kg) and OEA (5 mg/kg) co-administration over 6 days enhanced the reduction of both food intake and body weight gain, increased the energy expenditure and reduced the respiratory quotient (VCO2/VO2). This negative energy balance agreed with decreased fat mass and increased BAT weight and temperature, as well as with lowered plasma levels of triglycerides, cholesterol, nonessential fatty acids (NEFAs), and the adipokines leptin and TNF-α. Regarding eWAT, CL316243 and OEA treatment elevated levels of the thermogenic factors PPARα and UCP1, reduced p38-MAPK phosphorylation, and promoted brown-like features in the white adipocytes: the mitochondrial (Cox4i1, Cox4i2) and BAT (Fgf21, Prdm16) genes were overexpressed in eWAT. The enhancement of the fatty-acid β-oxidation factors Cpt1b and Acox1 in eWAT was accompanied by an upregulation of de novo lipogenesis and reduced expression of the unsaturated-fatty-acid-synthesis enzyme gene, Scd1. We propose that the combination of β-adrenergic and PPARα receptor agonists promotes therapeutic adipocyte remodelling in eWAT, and therefore has a potential clinical utility in the treatment of obesity.KEY WORDS: CL316243Peroxisome proliferator-activated receptor alpha, β3-adrenergic receptor, Thermogenesis, β-oxidation, Adipocyte 相似文献
998.
Giuliano Pinna Claudio Pascale Paolo Fornengo Sebastiana Arras Carmela Piras Pietro Panzarasa Gianpaolo Carmosino Orietta Franza Vincenzo Semeraro Salvatore Lenti Susanna Pietrelli Sergio Panzone Christian Bracco Roberto Fiorini Giovanni Rastelli Daniela Bergandi Bruno Zampaglione Roberto Musso Claudio Marengo Giancarlo Santoro Sergio Zamboni Barbara Traversa Maddalena Barattini Graziella Bruno 《PloS one》2014,9(4)
Epidemiological data on the impact of hypertensive crises (emergencies and urgencies) on referral to the Emergency Departments (EDs) are lacking, in spite of the evidence that they may be life-threatening conditions. We performed a multicenter study to identify all patients aged 18 years and over who were admitted to 10 Italian EDs during 2009 for hypertensive crises (systolic blood pressure ≥220 mmHg and/or diastolic blood pressure ≥120 mmHg). We classified patients as affected by either hypertensive emergencies or hypertensive urgencies depending on the presence or the absence of progressive target organ damage, respectively. Logistic regression analysis was then performed to assess variables independently associated with hypertensive emergencies with respect to hypertensive urgencies. Of 333,407 patients admitted to the EDs over the one-year period, 1,546 had hypertensive crises (4.6/1,000, 95% CI 4.4–4.9), and 23% of them had unknown hypertension. Hypertensive emergencies (n = 391, 25.3% of hypertensive crises) were acute pulmonary edema (30.9%), stroke (22.0%,), myocardial infarction (17.9%), acute aortic dissection (7.9%), acute renal failure (5.9%) and hypertensive encephalopathy (4.9%). Men had higher frequency than women of unknown hypertension (27.9% vs 18.5%, p<0.001). Even among known hypertensive patients, a larger proportion of men than women reported not taking anti-hypertensive drug (12.6% among men and 9.4% among women (p<0.001). Compared to women of similar age, men had higher likelihood of having hypertensive emergencies than urgencies (OR = 1.34, 95% CI 1.06–1.70), independently of presenting symptoms, creatinine, smoking habit and known hypertension. This study shows that hypertensive crises involved almost 5 out of 1,000 patients-year admitted to EDs. Sex differences in frequencies of unknown hypertension, compliance to treatment and risk of hypertensive emergencies might have implications for public health programs. 相似文献
999.
Sergio E. Starkstein Wendy A. Davis Milan Dragovic Violetta Cetrullo Timothy M. E. Davis David G. Bruce 《PloS one》2014,9(11)
BackgroundWhile depression is a frequent psychiatric comorbid condition in diabetes and has significant clinical impact, the syndromal profile of depression and anxiety symptoms has not been examined in detail.AimsTo determine the syndromal pattern of the depression and anxiety spectrum in a large series of patients with type 2 diabetes, as determined using a data-driven approach based on latent class analysis (LCA).MethodType 2 diabetes participants from the observational community-based Fremantle Diabetes Study Phase II underwent assessment of lifetime depression using the Brief Lifetime Depression Scale, the Patient Health Questionnaire 9-item version (PHQ-9) for current depression symptoms, and the Generalized Anxiety Disorder Scale that was specifically developed and validated for this study. The main outcome measure was classes of patients with a specific syndromal profile of depression and anxiety symptoms based on LCA.ResultsLCA identified four classes that were interpreted as “major anxious depression”, “minor anxious depression”, “subclinical anxiety”, and “no anxious depression”. All nine DSM-IV/5 diagnostic criteria for major depression identified a class with a high frequency of major depression. All symptoms of anxiety had similar high probabilities as symptoms of depression for the “major depression-anxiety” class. There were significant differences between classes in terms of history of depression and anxiety, use of psychoactive medication, and diabetes-related variables.ConclusionsPatients with type 2 diabetes show specific profiles of depression and anxiety. Anxiety symptoms are an integral part of major depression in type 2 diabetes. The different classes identified here provide empirically validated phenotypes for future research. 相似文献
1000.
Mara S. Roset Andrés E. Iba?ez Job Alves de Souza Filho Juan M. Spera Leonardo Minatel Sergio C. Oliveira Guillermo H. Giambartolomei Juliana Cassataro Gabriel Briones 《PloS one》2014,9(7)
Brucella, the etiological agent of animal and human brucellosis, is a bacterium with the capacity to modulate the inflammatory response. Cyclic β-1,2-glucan (CβG) is a virulence factor key for the pathogenesis of Brucella as it is involved in the intracellular life cycle of the bacteria. Using comparative studies with different CβG mutants of Brucella, cgs (CβG synthase), cgt (CβG transporter) and cgm (CβG modifier), we have identified different roles for this polysaccharide in Brucella. While anionic CβG is required for bacterial growth in low osmolarity conditions, the sole requirement for a successful Brucella interaction with mammalian host is its transport to periplasmic space. Our results uncover a new role for CβG in promoting splenomegaly in mice. We showed that CβG-dependent spleen inflammation is the consequence of massive cell recruitment (monocytes, dendritics cells and neutrophils) due to the induction of pro-inflammatory cytokines such as IL-12 and TNF-α and also that the reduced splenomegaly response observed with the cgs mutant is not the consequence of changes in expression levels of the characterized Brucella PAMPs LPS, flagellin or OMP16/19. Complementation of cgs mutant with purified CβG increased significantly spleen inflammation response suggesting a direct role for this polysaccharide. 相似文献