999 resultados para Backbone-cyclized Proteins Database
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Purpose: We have previously demonstrated that mutations in the FAM161A gene, encoding a protein with unknown function and no similarities with other characterized sequences, cause autosomal recessive retinitis pigmentosa (RP). The purpose of this work is to investigate the functional role of FAM161A within the retina and its relationship with other proteins involved in RP. Methods: The subcellular localization of FAM161A in the retina was assessed by immunohistochemistry of retinal sections and dissociated photoreceptors from mice, which were stained using antibodies against FAM161A and antibodies against cilium markers. The function of FAM161A was further assessed in ciliated mammalian cell lines by expression of recombinant FAM161A with various fusion tags. The binary interaction between FAM161A and a collection of ciliary and ciliopathy-associated proteins was analyzed using a yeast two-hybrid assay. The results obtained with this technique were validated using independent protein-protein interaction assays (GST-pull downs, co-transfection and co-immunoprecipitation). Results: Native FAM161A localized at the connecting cilium of photoreceptor cells, as demonstrated by immunofluorescence in both dissociated photoreceptors and retinal sections of mice. More specifically, co-staining with markers for ciliary sub-structures (RPGRIP1L, Centrin, RP1, GT335) demonstrated that FAM161A decorated the basal body and the very apical part of the connecting cilium. Upon overexpression in ciliated cultured mammalian cells, FAM161A localized to the ciliary basal body. Yeast two-hybrid analysis of the binary interaction of FAM161A and an array of ciliary proteins revealed the direct interaction of FAM161A with three proteins of which the cognate genes are mutated in retinal ciliopathies. The confirmation of these interactions using different biochemical assays is currently in progress. Conclusions: FAM161A is a ciliary basal body protein of the photoreceptor connecting cilium, rendering the associated RP as a novel retinal ciliopathy. The confined expression of FAM161A in the retina and the direct interaction of FAM161A with other retinal ciliopathy-associated proteins may explain the retinal phenotype of this specific subset of mechanistically and phenotypically connected retinal disorders.
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The aim of this work is to introduce a systematic press database on natural hazards and climate change in Catalonia (NE of Spain) and to analyze its potential application to social-impact studies. For this reason, a review of the concepts of risk, hazard, vulnerability and social perception is also included. This database has been built for the period 1982¿2007 and contains all the news related with those issues published by the oldest still-active newspaper in Catalonia. Some parameters are registered for each article and for each event, including criteria that enable us to determine the importance accorded to it by the newspaper, and a compilation of information about it. This ACCESS data base allows each article to be classified on the basis of the seven defined topics and key words, as well as summary information about the format and structuring of the new itself, the social impact of the event and data about the magnitude or intensity of the event. The coverage given to this type of news has been assessed because of its influence on construction of the social perception of natural risk and climate change, and as a potential source of information about them. The treatment accorded by the press to different risks is also considered. More than 14 000 press articles have been classified. Results show that the largest number of news items for the period 1982¿2007 relates to forest fires and droughts, followed by floods and heavy rainfalls, although floods are the major risk in the region of study. Two flood events recorded in 2002 have been analyzed in order to show an example of the role of the press information as indicator of risk perception.
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One of the aims of the MEDEX project is to improve the knowledge of high-impact weather events in the Mediterranean. According to the guidelines of this project, a pilot study was carried out in two regions of Spain (the Balearic Islands and Catalonia) by the Social Impact Research group of MEDEX. The main goal is to suggest some general and suitable criteria about how to analyse requests received in Meteorological Services arising out of the damage caused by weather events. Thus, all the requests received between 2000 and 2002 at the Servei Meteorològic de Catalunya as well as at the Division of AEMET in the Balearic Islands were analysed. Firstly, the proposed criteria in order to build the database are defined and discussed. Secondly, the temporal distribution of the requests for damage claims is analysed. On average, almost half of them were received during the first month after the event happened. During the first six months, the percentage increases by 90%. Thirdly, various factors are taken into account to determine the impact of specific events on society. It is remarkable that the greatest number of requests is for those episodes with simultaneous heavy rain and strong wind, and finally, those that are linked to high population density.
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The NW Mediterranean region experiences every year heavy rainfall and flash floods that occasionally produce catastrophic damages. Less frequent are floods that affect large regions. Although a large number of databases devoted exclusively to floods or considering all kind of natural hazards do exist, usually they only record catastrophic flood events. This paper deals with the new flood database that is being developed within the framework of HYMEX project. Results are focused on four regions representative of the NW sector of Mediterranean Europe: Catalonia, Spain; the Balearic Islands, Spain; Calabria, Italy; and Languedoc-Roussillon, Midi-Pyrenées and PACA, France. The common available 30-yr period starts in 1981 and ends in 2010. The paper shows the database structure and criteria, the comparison with other flood databases, some statistics on spatial and temporal distribution, and an identification of the most important events. The paper also provides a table that includes the date and affected region of all the catastrophic events identified in the regions of study, in order to make this information available for all audiences.
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The vast majority of eukaryotic organisms reproduce sexually, yet the nature of the sexual system and the mechanism of sex determination often vary remarkably, even among closely related species. Some species of animals and plants change sex across their lifespan, some contain hermaphrodites as well as males and females, some determine sex with highly differentiated chromosomes, while others determine sex according to their environment. Testing evolutionary hypotheses regarding the causes and consequences of this diversity requires interspecific data placed in a phylogenetic context. Such comparative studies have been hampered by the lack of accessible data listing sexual systems and sex determination mechanisms across the eukaryotic tree of life. Here, we describe a database developed to facilitate access to sexual system and sex chromosome information, with data on sexual systems from 11,038 plant, 705 fish, 173 amphibian, 593 non-avian reptilian, 195 avian, 479 mammalian, and 11,556 invertebrate species.
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Reviews growth in database production in Catalonia (ASCII, videotext, CD-ROM) over the past decade, with particular attention to the level of development, classification of producers, distribution, users and language. Examines the principal problems affecting the Catalan context: the lack of an informationand documentation policy, deficiencies in distribution of databases, the special situation in telecommunications, insufficient financial resources and the lack of specialized personnel.
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Clin Microbiol Infect ABSTRACT: The aetiological diagnosis of community-acquired pneumonia (CAP) is challenging in children, and serological markers would be useful surrogates for epidemiological studies of pneumococcal CAP. We compared the use of anti-pneumolysin (Ply) antibody alone or with four additional pneumococcal surface proteins (PSPs) (pneumococcal histidine triad D (PhtD), pneumococcal histidine triad E (PhtE), LytB, and pneumococcal choline-binding protein A (PcpA)) as serological probes in children hospitalized with CAP. Recent pneumococcal exposure (positive blood culture for Streptococcus pneumoniae, Ply(+) blood PCR finding, and PSP seroresponse) was predefined as supporting the diagnosis of presumed pneumococcal CAP (P-CAP). Twenty-three of 75 (31%) children with CAP (mean age 33.7 months) had a Ply(+) PCR finding and/or a ≥2-fold increase of antibodies. Adding seroresponses to four PSPs identified 12 additional patients (35/75, 45%), increasing the sensitivity of the diagnosis of P-CAP from 0.44 (Ply alone) to 0.94. Convalescent anti-Ply and anti-PhtD antibody titres were significantly higher in P-CAP than in non P-CAP patients (446 vs. 169 ELISA Units (EU)/mL, p 0.031, and 189 vs. 66 EU/mL, p 0.044), confirming recent exposure. Acute anti-PcpA titres were three-fold lower (71 vs. 286 EU/mL, p <0.001) in P-CAP children. Regression analyses confirmed a low level of acute PcpA antibodies as the only independent predictor (p 0.002) of P-CAP. Novel PSPs facilitate the demonstration of recent pneumococcal exposure in CAP children. Low anti-PcpA antibody titres at admission distinguished children with P-CAP from those with CAP with a non-pneumococcal origin.
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Non-infarcted myocardium after coronary occlusion undergoes progressive morphological and functional changes. The purpose of this study was to determine whether non-infarcted myocardium exhibits (1) alteration of the substrate pattern of myocardial metabolism and (2) concomitant changes in the expression of regulatory proteins of glucose and fatty acid metabolism. Myocardial infarction was induced in rats by ligation of the left coronary artery. One day and eight weeks after coronary occlusion, glucose and palmitate oxidation were measured. Expression of selected proteins of metabolism were determined one day to 12 weeks after infarction. One day after coronary occlusion no difference of glucose and palmitate oxidation was detectable, whereas after eight weeks, glucose oxidation was increased (+84%, P<0.05) and palmitate oxidation did not change significantly (-19%, P=0.07) in infarct-containing hearts, compared with hearts from sham-operated rats. One day after coronary occlusion, myocardial mRNA expression of the glucose transporter GLUT-1 was increased (+86%, P<0.05) and the expression of GLUT-4 was decreased (-28%, P<0.05) in surviving myocardium of infarct-containing hearts. Protein level of GLUT-1 was increased (+81%, P<0.05) and that of GLUT-4 slightly, but not significantly, decreased (-16%, P=NS). mRNA expressions of heart fatty acid binding protein (H-FABP), and of medium chain acyl-CoA dehydrogenase (MCAD), were decreased by 36% (P<0.05) and 35% (P=0. 07), respectively. Eight weeks after acute infarction, the left ventricle was hypertrophied and, at this time-point, there was no difference in the expression of GLUT-1 and GLUT-4 between infarcted and sham-operated hearts. However, myocardial mRNA and protein content of MCAD were decreased by 30% (P<0.01) and 27% (P<0.05), respectively. In summary, in surviving myocardium, glucose oxidation was increased eight weeks after coronary occlusion. Concomitantly, mRNA and protein expression of MCAD were decreased, compatible with a role of altered expression of regulatory proteins of metabolism in post-infarction modification of myocardial metabolism.
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In response to stress or injury the heart undergoes a pathological remodeling process, associated with hypertrophy, cardiomyocyte death and fibrosis, that ultimately causes cardiac dysfunction and heart failure. It has become increasingly clear that signaling events associated with these pathological cardiac remodeling events are regulated by scaffolding and anchoring proteins, which allow coordination of pathological signals in space and time. A-kinase anchoring proteins (AKAPs) constitute a family of functionally related proteins that organize multiprotein signaling complexes that tether the cAMP-dependent protein kinase (PKA) as well as other signaling enzymes to ensure integration and processing of multiple signaling pathways. This review will discuss the role of AKAPs in the cardiac response to stress. Particular emphasis will be given to the adaptative process associated with cardiac hypoxia as well as the remodeling events linked to cardiac hypertrophy and heart failure. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Cardiac Pathways of Differentiation, Metabolism and Contraction.
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Although research on influenza lasted for more than 100 years, it is still one of the most prominent diseases causing half a million human deaths every year. With the recent observation of new highly pathogenic H5N1 and H7N7 strains, and the appearance of the influenza pandemic caused by the H1N1 swine-like lineage, a collaborative effort to share observations on the evolution of this virus in both animals and humans has been established. The OpenFlu database (OpenFluDB) is a part of this collaborative effort. It contains genomic and protein sequences, as well as epidemiological data from more than 27,000 isolates. The isolate annotations include virus type, host, geographical location and experimentally tested antiviral resistance. Putative enhanced pathogenicity as well as human adaptation propensity are computed from protein sequences. Each virus isolate can be associated with the laboratories that collected, sequenced and submitted it. Several analysis tools including multiple sequence alignment, phylogenetic analysis and sequence similarity maps enable rapid and efficient mining. The contents of OpenFluDB are supplied by direct user submission, as well as by a daily automatic procedure importing data from public repositories. Additionally, a simple mechanism facilitates the export of OpenFluDB records to GenBank. This resource has been successfully used to rapidly and widely distribute the sequences collected during the recent human swine flu outbreak and also as an exchange platform during the vaccine selection procedure. Database URL: http://openflu.vital-it.ch.
Contribution of the gap junction proteins Connexin40 and Connexin43 to the control of blood pressure
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Summary Cells in tissues and organs coordinate their activities by communicating with each other through intercellular channels named gap junctions. These channels are conduits between the cytoplasmic compartments of adjacent cells, allowing the exchange of small molecules which may be crucial for hormone secretion. Renin is normally secreted in a regulated manner by specific cells of the juxtaglomerular apparatus located within the renal cortex. Gap junctional communication may be requisite to maintain an accurate functioning in coordination of renin-producing cells, more especially as renin is of paramount importance for the control of blood pressure. Connexin43 (Cx43) and Cx40 form gap junctions that link in vivo the cells of the juxtaglomerular apparatus. Cx43 links the endothelial cells, whereas gap junctions made of Cx40 connect the endothelial cells, the renin secreting cells, as well as the endothelial cells of to the renin-secreting cells of the afferent arteriole. The observation that loss of Cx40 results in chronic hypertension associated with altered vasomotion and signal conduction along arterioles, has lead us to suggest that connexins may contribute to control blood pressure by participating to the integration of various mechanical, osmotic and electrochemical stimuli involved in the control of renin secretion and by mediating the adaptive changes of the vascular wall induced by elevated blood pressure and mechanical stress. We therefore postulated that the absence of Cx40 could have deleterious effects on the coordinated functioning of the renin-containing cells, hence accounting for hypertension. In the first part of my thesis, we reported that Cx40-deficient mice (Cx40) are hypertensive due to increased plasma renin levels and numbers of renin-producing cells. Besides, we demonstrated that prostaglandins and nitric oxide, which are possible mediators in the regulation of renin secretion by the macula densa, exert a critical role in the mechanisms controlling blood pressure ín Cx40 knockout hypertensive mice. In view of previous studies that stated avessel-specifc increase in the expression of Cx43 during renin-dependent hypertension, we hypothesized that Cx43 channels are particularly well-matched to integrate the response of cells constituting the vascular wall to hypertensive conditions. Using transgenic mice in which Cx43 was replaced by Cx32, we revealed that the replacement of Cx43 by Cx32 is associated with decreased expression and secretion of renin and prevent the renin-dependent hypertension which is normally induced in the 2K1C model. To gain insights into the regulation of connexins in two separate tissues exposed to the same fluid pressure, the second part of my thesis work was dedicated to the study of the impact of chronic hypertension and related hypertrophy on the expression of the cardiovascular connexins (Cx40, Cx37, Cx43 and Cx45) in mouse aorta and heart. Our results documented that the expression of connexins is differentially regulated in mouse aorta. according to the models of hypertension. Thus, blood pressure induces mechanical forces that differentially alter the expression of vascular connexins in order to respond to an adaptation of the aortic wall observed under pathological conditions. Altogether these data provide the first evidences that intercellular communication mediated by gap junctions is required for a proper renin secretion from the juxtaglomerular apparatus in order to control blood pressure.
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Glycosyl phosphatidylinositol (GPI)-anchored proteins contain in their COOH-terminal region a peptide segment that is thought to direct glycolipid addition. This signal has been shown to require a pair of small amino acids positioned 10-12 residues upstream of an hydrophobic C-terminal domain. We analysed the contribution of the region separating the anchor acceptor site and the C-terminal hydrophobic segment by introducing amino acid deletions and substitutions in the spacer element of the GPI-anchored Thy-1 glycoprotein. Deletions of 7 amino acids in this region, as well as the introduction of 2 charged residues, prevented the glycolipid addition to Thy-1, suggesting that the length and the primary sequence of the spacer domain are important determinants in the signal directing GPI anchor transfer onto a newly synthesized polypeptide. Furthermore, we tested these rules by creating a truncated form of the normally transmembranous Herpes simplex virus I glycoprotein D (gDI) and demonstrating that when its C-terminal region displays all the features of a GPI-anchored protein, it is able to direct glycolipid addition onto another cell surface molecule.
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Surface molecules of Staphylococcus aureus are involved in the colonization of vascular endothelium which is a crucial primary event in the pathogenesis of infective endocarditis (IE). The ability of these molecules to also launch endothelial procoagulant and proinflammatory responses, which characterize IE, is not known. In the present study we investigated the individual capacities of three prominent S. aureus surface molecules; fibronectin-binding protein A (FnBPA) and B (FnBPB) and clumping factor A (ClfA), to promote bacterial adherence to cultured human endothelial cells (ECs) and to activate phenotypic and functional changes in these ECs. Non-invasive surrogate bacterium Lactococcus lactis, which, by gene transfer, expressed staphylococcal FnBPA, FnBPB or ClfA molecules were used. Infection of ECs increased 50- to 100-fold with FnBPA- or FnBPB-positive recombinant lactococci. This coincided with EC activation, interleukin-8 secretion and surface expression of ICAM-1 and VCAM-1 and concomitant monocyte adhesion. Infection with ClfA-positive lactococci did not activate EC. FnBPA-positive L. lactis also induced a prominent tissue factor-dependent endothelial coagulation response that was intensified by cell-bound monocytes. Thus S. aureus FnBPs, but not ClfA, confer invasiveness and pathogenicity to non-pathogenic L. lactis organisms indicating that bacterium-EC interactions mediated by these adhesins are sufficient to evoke inflammation as well as procoagulant activity at infected endovascular sites.
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Selostus: Heraproteiinit terveysvaikutteisten elintarvikkeiden kehittämisessä