918 resultados para Node-Depth Encoding


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Developmentally regulated mechanisms involving alternative RNA splicing and/or polyadenylation, as well as transcription termination, are implicated in controlling the levels of secreted mu (mu s), membrane mu (mu m) and delta immunoglobulin (Ig) heavy chain mRNAs during B cell differentiation (mu gene encodes the mu heavy chain). Using expression vectors constructed with genomic DNA segments composed of the mu m polyadenylation signal region, we analyzed poly(A) site utilization and termination of transcription in stably transfected myeloma cells and in murine fibroblast L cells. We found that the gene segment containing the mu m poly(A) signals, along with 536 bp of downstream flanking sequence, acted as a transcription terminator in both myeloma cells and L cell fibroblasts. Neither a 141-bp DNA fragment (which directed efficient polyadenylation at the mu m site), nor the 536-bp flanking nucleotide sequence alone, were sufficient to obtain a similar regulation. This shows that the mu m poly(A) region plays a central role in controlling developmentally regulated transcription termination by blocking downstream delta gene expression. Because this gene segment exhibited the same RNA processing and termination activities in fibroblasts, it appears that these processes are not tissue-specific.

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To investigate a recently developed lymphadenopathy can be simple or complex. The medical history, presence or not of symptoms, the general physical examination, and the localization and characteristics of the adenopathy, most often lead to a diagnosis and therapy when indicated. Among young adults, the etiology is either infectious or reactive, rarely tumoral, as opposed to elderly persons. The most important step is to look at signs of severity (or non banality) such as an increased size, hard consistency, supra-clavicular location, an immunocompromised host, a history of Tb exposition. If present, these signs will trigger a biopsy with cyto- or histopathological examination mostly to rule out a malignant tumor. This article reviews the practical steps of an investigation of an isolated adenopathy in an adult patient.

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The mature TCR is composed of a clonotypic heterodimer (alpha beta or gamma delta) associated with the invariant CD3 components (gamma, delta, epsilon and zeta). There is now considerable evidence that more immature forms of the TCR-CD3 complex (consisting of either CD3 alone or CD3 associated with a heterodimer of TCR beta and pre-T alpha) can be expressed at the cell surface on early thymocytes. These pre-TCR complexes are believed to be necessary for the ordered progression of early T cell development. We have analyzed in detail the expression of both the pre-TCR and CD3 complex at various stages of adult thymus development. Our data indicate that all CD3 components are already expressed at the mRNA level by the earliest identifiable (CD4lo) thymic precursor. In contrast, genes encoding the pre-TCR complex (pre-T alpha and fully rearranged TCR beta) are first expressed at the CD44loCD25+CD4-CD8- stage. Detectable surface expression of both CD3 and TCR beta are delayed relative to expression of the corresponding genes, suggesting the existence of other (as yet unidentified) components of the pre-TCR complex.

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INTRODUCTION: International Breast Cancer Study Group (IBCSG) Trial 11-93 is the largest trial evaluating the role of the addition of chemotherapy to ovarian function suppression/ablation (OFS) and tamoxifen in premenopausal patients with endocrine-responsive early breast cancer. METHODS: IBCSG Trial 11-93 is a randomized trial comparing four cycles of adjuvant chemotherapy (AC: doxorubicin or epirubicin, plus cyclophosphamide) added to OFS and 5 years of tamoxifen versus OFS and tamoxifen without chemotherapy in premenopausal patients with node-positive, endocrine-responsive early breast cancer. There were 174 patients randomized from May 1993 to November 1998. The trial was closed before the target accrual was reached due to low accrual rate. RESULTS: Patients randomized tended to have lower risk node-positive disease and the median age was 45. After 10 years median follow up, there remains no difference between the two randomized treatment groups for disease-free (hazard ratio=1.02 (0.57-1.83); P=0.94) or overall survival (hazard ratio=0.97 (0.44-2.16); P=0.94). CONCLUSION: This trial, although small, offers no evidence that AC chemotherapy provides additional disease control for premenopausal patients with lower-risk node-positive endocrine-responsive breast cancer who receive adequate adjuvant endocrine therapy. A large trial is needed to determine whether chemotherapy adds benefit to endocrine therapy for this population.

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PURPOSE: Pharmacovigilance methods have advanced greatly during the last decades, making post-market drug assessment an essential drug evaluation component. These methods mainly rely on the use of spontaneous reporting systems and health information databases to collect expertise from huge amounts of real-world reports. The EU-ADR Web Platform was built to further facilitate accessing, monitoring and exploring these data, enabling an in-depth analysis of adverse drug reactions risks.METHODS: The EU-ADR Web Platform exploits the wealth of data collected within a large-scale European initiative, the EU-ADR project. Millions of electronic health records, provided by national health agencies, are mined for specific drug events, which are correlated with literature, protein and pathway data, resulting in a rich drug-event dataset. Next, advanced distributed computing methods are tailored to coordinate the execution of data-mining and statistical analysis tasks. This permits obtaining a ranked drug-event list, removing spurious entries and highlighting relationships with high risk potential.RESULTS: The EU-ADR Web Platform is an open workspace for the integrated analysis of pharmacovigilance datasets. Using this software, researchers can access a variety of tools provided by distinct partners in a single centralized environment. Besides performing standalone drug-event assessments, they can also control the pipeline for an improved batch analysis of custom datasets. Drug-event pairs can be substantiated and statistically analysed within the platform's innovative working environment.CONCLUSIONS: A pioneering workspace that helps in explaining the biological path of adverse drug reactions was developed within the EU-ADR project consortium. This tool, targeted at the pharmacovigilance community, is available online at https://bioinformatics.ua.pt/euadr/. Copyright © 2012 John Wiley & Sons, Ltd.

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RESUME : Les dermatophytes sont les agents infectieux les plus fréquents responsables de la plupart des mycoses superficielles chez les humains et chez les animaux. Ces infections, dermatophytoses, également appelées tineas ou teignes, sont fréquentes et causent des problèmes de santé publique au niveau mondial. La capacité d'envahir et de progresser au sein des structures kératinisées est probablement liée à la sécrétion de différentes enzymes kératinolytiques, qui sont considérées comme la principale caractéristique liée à la pathogénicité de ces champignons. L'objectif de ma thèse a été premièrement de progresser dans l'identification et la caractérisation des nouvelles protéines sécrétées, afin de mieux comprendre a) la capacité globale des dermatophytes à envahir les structures kératinisées, et b) les différences dans la virulence et la spécificité d'hôte que présentent les espèces étudiées .Pour progresser dans l'identification et la caractérisation de ces nouvelles protéines, les secretomes de six espèces de dermatophytes (Trichophyton rubrum, Trichophyton violaceum, Trichophyton soudanense, Trichophyton equinum, Arthroderma vanbreuseghemii et Trichophyton tonsurans) ont été étudiés. Bien qu'il y ait un niveau globalement élevé de similitude entre les protéases sécrétées, les différentes espèces de dermatophytes sécrètent des profiles protéiques distincts lorsqu'elles sont cultivées dans les mêmes conditions de culture, et donc une signature spécifique a pu être associé à chaque espèce. Ces profiles ont été un outil avantageux pour identifier et cartographier les protéines orthologues aux six espèces et ont aussi permit la discrimination d'espèces très proches comme T. tonsurans et T. equinum qui ne peuvent pas être différenciées par l'ADN ribosomal. Ce travail également présente ce que l'on croit être la première identification global des protéines sécrétées par les dermatophytes dans des conditions de culture que incitent l'activité protéolytique extracellulaire. Ce catalogue de protéines, comprenant des endo- and exo- proteases, autres hydrolases, oxydoreductases et des protéines avec fonction inconnue, représente probablement le spectre d'enzymes qui permettent la dégradation des tissus kératinisés en composés qui peuvent être assimilés par le champignon. Les résultats suggèrent qu'un changement écologique pourrait être associé à une expression différentielle des gènes codant les protéines sécrétées, en particulier, les protéases, plutôt qu'à des divergences génétiques au niveau des gènes codant les protéines orthologues. Une sécrétion différentielle des protéines par les dermatophytes pourrait également être responsable de la variabilité inflammatoire qui causent ces agents infectieux chez les différents hôtes. Par conséquent, les protéines identifiées ici sont également importantes pour faire la lumière sur la réponse immunitaire de l'hôte au cours du processus infectieux. SUMMARY : Dermatophytes are the most common infectious agents responsible for superficial mycosis in humans and animals. Dermatophytoses, also called tineas or ringworm, are frequent and cause public health problems worldwide. The secretion of different keratinolytic enzymes is believed to be a key pathogenicity-related characteristic of these fungi. The aim of this work was first to progress in the identification and characterization of novel secreted proteins, in order to better understand a) the overall capability of dermatophytes to invade keratinised structures, and b) differences in virulence and host-specificity of the investigated species. To progress in the identification and characterization of novel proteins, the secretomes from Trichophyton rubrum, Trichophyton violaceum, Trichophyton soudanense, Trichophyton equinum, Arthroderma vanbreuseghemii and Trichophyton tonsurans were studied. Although there is a high global level of similarity among the secreted proteases, different dermatophyte species produce distinct patterns of proteins when grown in the same culture medium, and so a specific signature could be associated to each species. These patterns were useful to identify and map orthologous proteins among the six species, as well as to discriminate the closely related species T. tonsurans and T. equinum, which cannot be differentiated by ribosomal DNA. This work also presents the first in-depth identification of the major proteins secreted by dermatophytes growing under conditions promoting extracellular proteolytic activity. This catalogue of proteins, which include several endo- and exo- proteases, other hydrolases, oxydoreductases, and proteins of unknown function, probably represents the spectrum of enzymes that allow the degradation of keratinized tissues into compounds which can be assimilated by the fungus. The results suggest that ecological switching could be related to a differential expression of genes encoding secreted proteins, particularly, proteases, rather than genetic divergences of the genes encoding orthologous proteins. Differential secretion of proteins by Dermatophyte species could also be responsible for the variable inflammation caused by the infectious agent within the host. Therefore, the proteins here identified are also important to shed light into the immune response of the host during the infection process.

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With inflation, there is no longer a completely adequate budget for highway construction and maintenance. Restricted budgets have generated development and implementation of pavement management programs. A need for management guidelines generated National Cooperative Highway Research Program Synthesis of Highway Practice 84, "Evaluation Criteria and Priority Setting for State Highway Programs". Traffic volumes and present conditions are two major factors in determining the priority of a proposed highway improvement. The Iowa DOT, Highway Division, Office of Materials has been conducting pavement condition inventory surveys on a three-year frequency since 1969 as input for pavement management. Development of substantial wheel rutting on paved roadways results in a potential hazard to highway safety. During periods of rain, these water-filled ruts may cause hydroplaning and loss of vehicle control. It is, therefore, imparitive that Iowa roadways be continually monitored for rut depths and further that this data be used in a pavement management program to determine priorities for rehabilitation or resurfacing.

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SummarySecondary lymphoid organs, such as lymph nodes or spleen, are the only places in our body where primary adaptive immune responses are efficiently elicited. These organs have distinct Β and Τ cell rich zones and Τ lymphocytes constantly migrate from the bloodstream into Τ zones to scan dendritic cells (DCs) for antigens they present. Specialized fibroblasts, the Τ zone reticular cells (HR.Cs), span the Τ zone in the form a three-dimensional network. lK.Cs guide incoming Τ cells in their migration, both chemically, by the secretion of the chemokines CCL19 and CCL21, and physically, by construction of a road system to which also DCs adhere. In this way TRCs are thought to facilitate encounters of Τ cells with antigen-bearing DCs and thereby accelerate the selection of rare antigen-specific Τ cells. The resulting Τ cell activation, proliferation and differentiation all take place within the TRC network. However, the influence of TRCs on Τ cell activation has so fer not been elucidated with the possible reasons being that TRCs represent a relative rare cell population and that mice devoid of TRCs have not been described.To circumvent these technical limitations, we established TRC clones and lines to have an abundant source to functionally characterize TRCs. Both the clones and lines show a fibroblastic phenotype, express a surface marker profile comparable to ex vivo TRCs and produce extracellular matrix molecules. However, expression of Ccl19, Ccl21 and ZL-7 is lost and could not be restored by cytokine stimulation. When these TRC clones or lines were cultured in a three-dimensional cell culture system, their morphology changed and resembled that of in vivo TRCs as they formed networks. By adding Τ cells and antigen-loaded DCs to these cultures we successfully reconstructed lymphoid Τ zones that allowed antigen-specific Τ cell activation.To characterize the role of TRCs in Τ cell priming, TRCs were co-cultured with antigen-specific Τ cells in the presence antigen-loaded DCs. Surprisingly, the presence of TRC lines and ex vivo TRCs inhibited rather than enhanced CD8+ Τ cell activation, proliferation and effector cell differentiation. TRCs shared this feature with fibroblasts from non-lymphoid tissues as well as mesenchymal stromal cells. TRCs were identified as a strong source of nitric oxide (NO) thereby directly dampening Τ cell expansion as well as reducing the Τ cell priming capacity of DCs. The expression of inducible NO synthase (iNOS) was up- regulated in a subset of TRCs by both DC-signals as well as interferon-γ produced by primed CD8+ Τ cells. Importantly, iNOS expression was induced during viral infection in vivo in both lymph node TRCs and DCs. Consistent with a role for NO as a negative regulator, the primary Τ cell response was exaggerated in iNOS-/- mice. Our findings highlight that in addition to their established positive roles in Τ cell responses TRCs and DCs cooperate in a negative feedback loop to attenuate Τ cell expansion during acute inflammation.RésuméLes organes lymphoïdes secondaires, comme les ganglions lymphoïdes ou la rate, sont les seuls sites dans notre corps où la réponse primaire des lymphocytes Β et Τ est initiée efficacement. Ces organes ont des zones différentes, riches en cellules Β ou T. Des lymphocytes Τ circulent constamment du sang vers les zones T, où ils échantillonent la surface des cellules dendritiques (DCs) pour identifier les antigènes qu'ils présentent. Des fibroblastes spécialisés - nommés Τ zone reticular cells (TRCs)' forment un réseau tridimensionnel dans la zone T. Les TRCs guident la migration des cellules Τ par deux moyens: chimiquement, par la sécrétion des chimiokines CCL19 et CCL21 et physiquement, par la construction d'un réseau routier en trois dimensions, auquel adhèrent aussi des DCs. Dans ce? cas, on pense que la présence des TRCs facilite les rencontres entre les cellules Τ et les DCs chargées de l'antigène et accélère la sélection des rares cellules Τ spécifiques. Ensuite, l'activation de cellules T, ainsi que la prolifération et la différenciation se produisent toutes à l'intérieur du réseau des TRCs. L'influence des TRCs sur l'activation des cellules T n'est que très peu caractérisée, en partie parce que les TRCs représentent une population rare et que les souris déficientes dans les TRCs n'ont pas encore été découvertes.Pour contourner ces limitations techniques, nous avons établi des clones et des lignées cellulaires de TRC pour obtenir une source indéfinie de ces cellules permettant leur caractérisation fonctionnelle. Les clones et lignées établis ont un phénotype de fibroblaste, ils expriment des molécules de surface similaires aux TRCs ex vivo et produisent de la matrice extracellulaire. Mais l'expression de Ccl19, Ccl21 et 11-7 est perdue et ne peut pas être rétablie par stimulation avec différentes cytokines. Les clones TRC ou les lignées cultivées en un système tridimensionnel de culture cellulaire, montrent une morphologie changée, qui ressemble à celle de TRC ex vivo inclus la construction de réseaux tridimensionnels.Pour caractériser le rôle des TRC dans l'activation des cellules T, nous avons cultivé des TRCs avec des cellules T spécifiques et des DCs chargées avec l'antigène. Etonnamment, la présence des TRC (lignées et ex vivo) inhibait plutôt qu'elle améliorait l'activation, la prolifération et la différenciation des lymphocytes T CDS+. Les TRCs partageaient cette fonction avec des fibr-oblastes des organes non lymphoïdes et des cellules souches du type mésenchymateux. Dans ces conditions, les TRCs sont une source importante d'oxyde nitrique (NO) et par ce fait limitent directement l'expansion des cellules T et réduisent aussi la capacité des DCs à activer les cellules T. L'expression de l'enzyme NO synthase inductible (ïNOS) est régulée à la hausse par des signaux dérivés des DCs et par l'interféron-γ produit par des cellules T de type CD8+ activées. Plus important, l'expression d'iNOS est induite pendant une infection virale in vivo, dans les TRCs et dans les DCs. Par conséquent, la réponse primaire de cellules T est exagérée dans des souris iNOS-/-. Nos résultats mettent en évidence qu'en plus de leur rôle positif bien établi dans la réponse immunitaire, les TRCs et les DCs coopèrent dans une boucle de rétroaction négative pour atténuer l'expansion des cellules T pendant l'inflammation aigiie pour protéger l'intégrité et la fonctionnalité des organes lymphoïdes secondaires.

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We have investigated the impacts of 63 different low-molecular-weight compounds, most of them plant derived, on the in vitro expression of two antifungal biosynthetic genes by the plant-protecting rhizobacterium Pseudomonas fluorescens CHA0. The majority of the compounds tested affected the expression of one or both antifungal genes. This suggests that biocontrol activity in plant-beneficial pseudomonads is modulated by plant-bacterium signaling.

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We introduce a model of strategic thinking in games of initial response. Unlike standard level-k models, in this framework the player's `depth of reasoning' is endogenously determined, andit can be disentangled from his beliefs over his opponent's cognitive bound. In our approach,individuals act as if they follow a cost-benefit analysis. The depth of reasoning is a function ofthe player's cognitive abilities and his payoffs. The costs are exogenous and represent the gametheoretical sophistication of the player; the benefit instead is related to the game payoffs. Behavioris in turn determined by the individual's depth of reasoning and his beliefs about the reasoningprocess of the opponent. Thus, in our framework, payoffs not only affect individual choices inthe traditional sense, but they also shape the cognitive process itself. Our model delivers testableimplications on players' chosen actions as incentives and opponents change. We then test themodel's predictions with an experiment. We administer different treatments that vary beliefs overpayoffs and opponents, as well as beliefs over opponents' beliefs. The results of this experiment,which are not accounted for by current models of reasoning in games, strongly support our theory.Our approach therefore serves as a novel, unifying framework of strategic thinking that allows forpredictions across games.

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We sought to assess the feasibility and reproducibility of performing tissue-based immune characterization of the tumor microenvironment using CT-compatible needle biopsy material. Three independent biopsies were obtained intraoperatively from one metastatic epithelial ovarian cancer lesion of 7 consecutive patients undergoing surgical cytoreduction using a 16-gauge core biopsy needle. Core specimens were snap-frozen and subjected to immunohistochemistry (IHC) against human CD3, CD4, CD8, and FoxP3. A portion of the cores was used to isolate RNA for 1) real-time quantitative (q)PCR for CD3, CD4, CD8, FoxP3, IL-10 and TGF-beta, 2) multiplexed PCR-based T cell receptor (TCR) CDR3 Vβ region spectratyping, and 3) gene expression profiling. Pearson's correlations were examined for immunohistochemistry and PCR gene expression, as well as for gene expression array data obtained from different tumor biopsies. Needle biopsy yielded sufficient tissue for all assays in all patients. IHC was highly reproducible and informative. Significant correlations were seen between the frequency of CD3+, CD8+ and FoxP3+ T cells by IHC with CD3ε, CD8A, and FoxP3 gene expression, respectively, by qPCR (r=0.61, 0.86, and 0.89; all p< 0.05). CDR3 spectratyping was feasible and highly reproducible in each tumor, and indicated a restricted repertoire for specific TCR Vβ chains in tumor-infiltrating T cells. Microarray gene expression revealed strong correlation between different biopsies collected from the same tumor. Our results demonstrate a feasible and reproducible method of immune monitoring using CT-compatible needle biopsies from tumor tissue, thereby paving the way for sophisticated translational studies during tumor biological therapy.

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Viruses have developed strategies to counteract signalling through Toll-like receptors (TLRs) that are involved in the detection of viruses and induction of proinflammatory cytokines and IFNs. Vaccinia virus (VACV) encodes A46 protein which disrupts TLR signalling by interfering with TLR: adaptor interactions. Since the innate immune response to viruses is critical to induce protective immunity, we studied whether deletion of A46R gene in a NYVAC vector expressing HIV-1 Env, Gag, Pol and Nef antigens (NYVAC-C) improves immune responses against HIV-1 antigens. This question was examined in human macrophages and in mice infected with a single A46R deletion mutant of the vaccine candidate NYVAC-C (NYVAC-C-ΔA46R). The viral gene A46R is not required for virus replication in primary chicken embryo fibroblast (CEF) cells and its deletion in NYVAC-C markedly increases TNF, IL-6 and IL-8 secretion by human macrophages. Analysis of the immune responses elicited in BALB/c mice after DNA prime/NYVAC boost immunization shows that deletion of A46R improves the magnitude of the HIV-1-specific CD4 and CD8 T cell immune responses during adaptive and memory phases, maintains the functional profile observed with the parental NYVAC-C and enhances anti-gp120 humoral response during the memory phase. These findings establish the immunological role of VACV A46R on innate immune responses of macrophages in vitro and antigen-specific T and B cell immune responses in vivo and suggest that deletion of viral inhibitors of TLR signalling is a useful approach for the improvement of poxvirus-based vaccine candidates.

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The functional interaction of BAFF and APRIL with TNF receptor superfamily members BAFFR, TACI and BCMA is crucial for development and maintenance of humoral immunity in mice and humans. Using a candidate gene approach, we identified homozygous and heterozygous mutations in TNFRSF13B, encoding TACI, in 13 individuals with common variable immunodeficiency. Homozygosity with respect to mutations causing the amino acid substitutions S144X and C104R abrogated APRIL binding and resulted in loss of TACI function, as evidenced by impaired proliferative response to IgM-APRIL costimulation and defective class switch recombination induced by IL-10 and APRIL or BAFF. Family members heterozygous with respect to the C104R mutation and individuals with sporadic common variable immunodeficiency who were heterozygous with respect to the amino acid substitutions A181E, S194X and R202H had humoral immunodeficiency. Although signs of autoimmunity and lymphoproliferation are evident, the human phenotype differs from that of the Tnfrsf13b-/- mouse model.

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The objective of this study was to improve the simulation of node number in soybean cultivars with determinate stem habits. A nonlinear model considering two approaches to input daily air temperature data (daily mean temperature and daily minimum/maximum air temperatures) was used. The node number on the main stem data of ten soybean cultivars was collected in a three-year field experiment (from 2004/2005 to 2006/2007) at Santa Maria, RS, Brazil. Node number was simulated using the Soydev model, which has a nonlinear temperature response function [f(T)]. The f(T) was calculated using two methods: using daily mean air temperature calculated as the arithmetic average among daily minimum and maximum air temperatures (Soydev tmean); and calculating an f(T) using minimum air temperature and other using maximum air temperature and then averaging the two f(T)s (Soydev tmm). Root mean square error (RMSE) and deviations (simulated minus observed) were used as statistics to evaluate the performance of the two versions of Soydev. Simulations of node number in soybean were better with the Soydev tmm version, with a 0.5 to 1.4 node RMSE. Node number can be simulated for several soybean cultivars using only one set of model coefficients, with a 0.8 to 2.4 node RMSE.

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The Zein-2 component named Zc 1 corresponds to a storage protein of an apparent M.W. of 16 kDa present in maize endosperm.