954 resultados para BASE-LINE SYNDROME
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Este trabajo de investigación presenta los resultados de una revisión sistemática realizada a partir de la recopilación, lectura y análisis de distintas fuentes bibliográficas dentro de un conjunto heterogéneo consistente de 175 estudios que forman la base bibliográfica actual del documento “Cognitive Accessibility User Research” (W3C, 2015a) del W3C. Esta base bibliográfica está compuesta por publicaciones científicas basadas en libros, artículos, conferencias y sitios Web especializados, en los cuales se potencia como objeto particular de análisis, la indagación en la búsqueda de pautas de accesibilidad en las tecnologías Web que apoyen la integración a personas con discapacidad cognitiva. Como parte de este proceso de investigación se ha recopilado y descrito la situación actual, particularmente, de los retos en la utilización de las tecnologías de la información y la comunicación (TIC) en relación a personas con dificultades de aprendizaje o discapacidades cognitivas, tales como la Dislexia, Afasia, Trastorno de Aprendizaje No verbal, Envejecimiento-Demencia, Trastornos por Déficit de Atención con o sin Hiperactividad, Autismo, Síndrome de Down y Discalculia. Como aporte primordial de este Trabajo Fin de Master (TFM), se intenta trazar una línea de criterios que permitan la evaluación objetiva de este tópico, con miras a ofrecer un enfoque práctico y reciente sobre ésta temática, mostrando de forma esquematizada las pautas existentes y sirviendo de síntesis orientativa para el diseño accesible de las TIC con la finalidad de promover un soporte real a personas con los tipo de discapacidad cognitiva en los que se ha enfocado esta investigación. Logrando obtener como resultado principal de este estudio, 36 pautas generales que agrupan las coincidencias del grupo de discapacidades estudiadas y que han sido distribuidas en categorías: texto, navegación y generales, para su mejor interpretación y manejo de la Accesibilidad en las TIC´S para Personas con Discapacidad Cognitiva.---ABSTRACT---This research presents the results of a systematic review from collecting, reading and analysis of different bibliographic sources within a heterogeneous group consisting of 175 studies that form the basis of current literature document "Accessibility User Cognitive Research" (W3C , 2015th) of the W3C. This bibliographic database is composed of scientific publications based on books, articles, lectures and specialized Web sites, in which is enhanced as a particular object of analysis, the inquiry into the search for accessibility guidelines for Web technologies to support integration of people with cognitive disabilities. As part of this research process, the current situation has been collected and described, particularly the challenges in the use of information and communications technology (ICT) in relation to people with learning disabilities or cognitive disabilities, such as Dyslexia, aphasia, nonverbal learning disorder, aging-Dementia, Attention Deficit Disorders with or without hyperactivity, autism, Down syndrome and dyscalculia. As primary contribution of this Master's Thesis (TFM), it tries to draw a line of criteria to allow an objective assessment of this topic, in order to provide a practical and recent focus on this theme, showing schematically existing guidelines and serving as guidance for accessible design of ICT in order to promote a real support to people with cognitive disabilities where this research has focused on. Managing to obtain the main result of this study, 36 general guidelines that group the set of disabilities studied and have been distributed in categories: text, navigation and general, for better interpretation and management of ICTs for Accessibility people with cognitive disabilities.
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The peroxisome biogenesis disorders (PBDs), including Zellweger syndrome (ZS) and neonatal adrenoleukodystrophy (NALD), are autosomal recessive diseases caused by defects in peroxisome assembly, for which at least 10 complementation groups have been reported. We have isolated a human PEX1 cDNA (HsPEX1) by functional complementation of peroxisome deficiency of a mutant Chinese hamster ovary (CHO) cell line, ZP107, transformed with peroxisome targeting signal type 1-tagged “enhanced” green fluorescent protein. This cDNA encodes a hydrophilic protein (Pex1p) comprising 1,283 amino acids, with high homology to the AAA-type ATPase family. A stable transformant of ZP107 with HsPEX1 was morphologically and biochemically restored for peroxisome biogenesis. HsPEX1 expression restored peroxisomal protein import in fibroblasts from three patients with ZS and NALD of complementation group I (CG-I), which is the highest-incidence PBD. A CG-I ZS patient (PBDE-04) possessed compound heterozygous, inactivating mutations: a missense point mutation resulting in Leu-664 → Pro and a deletion of the sequence from Gly-634 to His-690 presumably caused by missplicing (splice site mutation). Both PBDE-04 PEX1 cDNAs were defective in peroxisome-restoring activity when expressed in the patient fibroblasts as well as in ZP107 cells. These results demonstrate that PEX1 is the causative gene for CG-I peroxisomal disorders.
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Aldosterone-dependent epithelial sodium transport in the distal nephron is mediated by the absorption of sodium through the highly selective, amiloride-sensitive epithelial sodium channel (ENaC) made of three homologous subunits (α, β, and γ). In human, autosomal recessive mutations of α, β, or γENaC subunits cause pseudohypoaldosteronism type 1 (PHA-1), a renal salt-wasting syndrome characterized by severe hypovolemia, high plasma aldosterone, hyponatremia, life-threatening hyperkaliemia, and metabolic acidosis. In the mouse, inactivation of αENaC results in failure to clear fetal lung liquid at birth and in early neonatal death, preventing the observation of a PHA-1 renal phenotype. Transgenic expression of αENaC driven by a cytomegalovirus promoter in αENaC(−/−) knockout mice [αENaC(−/−)Tg] rescued the perinatal lethal pulmonary phenotype and partially restored Na+ transport in renal, colonic, and pulmonary epithelia. At days 5–9, however, αENaC(−/−)Tg mice showed clinical features of severe PHA-1 with metabolic acidosis, urinary salt-wasting, growth retardation, and 50% mortality. Adult αENaC(−/−)Tg survivors exhibited a compensated PHA-1 with normal acid/base and electrolyte values but 6-fold elevation of plasma aldosterone compared with wild-type littermate controls. We conclude that partial restoration of ENaC-mediated Na+ absorption in this transgenic mouse results in a mouse model for PHA-1.
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Lowe syndrome is an X-linked disorder that has a complex phenotype that includes progressive renal failure and blindness. The disease is caused by mutations in an inositol polyphosphate 5-phosphatase designated OCRL. It has been shown that the OCRL protein is found on the surface of lysosomes and that a renal tubular cell line deficient in OCRL accumulated substrate phosphatidylinositol 4,5-bisphosphate. Because this lipid is required for vesicle trafficking from lysosomes, we postulate that there is a defect in lysosomal enzyme trafficking in patients with Lowe syndrome that leads to increased extracellular lysosomal enzymes and might lead to tissue damage and contribute to the pathogenesis of the disease. We have measured seven lysosomal enzymes in the plasma of 15 patients with Lowe syndrome and 15 age-matched male controls. We find a 1.6- to 2.0-fold increase in all of the enzymes measured. When the data was analyzed by quintiles of activity for all of the enzymes, we found that 95% of values in the lowest quintile come from normal subjects whereas in the highest quintile 85% of the values are from patients with Lowe syndrome. The increased enzyme levels are not attributable to renal insufficiency because there was no difference in enzyme activity in the four patients with the highest creatinine levels compared with the six patients with the lowest creatinine values.
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The congenital long QT syndrome (LQTS) is an inherited disorder characterized by a prolonged cardiac action potential. This delay in cellular repolarization can lead to potentially fatal arrhythmias. One form of LQTS (LQT3) has been linked to the human cardiac voltage-gated sodium channel gene (SCN5A). Three distinct mutations have been identified in the sodium channel gene. The biophysical and functional characteristics of each of these mutant channels were determined by heterologous expression of a recombinant human heart sodium channel in a mammalian cell line. Each mutation caused a sustained, non-inactivating sodium current amounting to a few percent of the peak inward sodium current, observable during long (>50 msec) depolarizations. The voltage dependence and rate of inactivation were altered, and the rate of recovery from inactivation was changed compared with wild-type channels. These mutations in diverse regions of the ion channel protein, all produced a common defect in channel gating that can cause the long QT phenotype. The sustained inward current caused by these mutations will prolong the action potential. Furthermore, they may create conditions that promote arrhythmias due to prolonged depolarization and the altered recovery from inactivation. These results provide insights for successful intervention in the disease.
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KCNQ1 encodes KCNQ1, which belongs to a family of voltage-dependent K+ ion channel proteins. KCNQ1 associates with a regulatory subunit, KCNE1, to produce the cardiac repolarizing current, IKs. Loss-of-function mutations in the human KCNQ1 gene have been linked to Jervell and Lange–Nielsen Syndrome (JLNS), a disorder characterized by profound bilateral deafness and a cardiac phenotype. To generate a mouse model for JLNS, we created a line of transgenic mice that have a targeted disruption in the Kcnq1 gene. Behavioral analysis revealed that the Kcnq1−/− mice are deaf and exhibit a shaker/waltzer phenotype. Histological analysis of the inner ear structures of Kcnq1−/− mice revealed gross morphological anomalies because of the drastic reduction in the volume of endolymph. ECGs recorded from Kcnq1−/− mice demonstrated abnormal T- and P-wave morphologies and prolongation of the QT and JT intervals when measured in vivo, but not in isolated hearts. These changes are indicative of cardiac repolarization defects that appear to be induced by extracardiac signals. Together, these data suggest that Kcnq1−/− mice are a potentially valuable animal model of JLNS.
Somatic mosaicism in Wiskott–Aldrich syndrome suggests in vivo reversion by a DNA slippage mechanism
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Somatic mosaicism caused by in vivo reversion of inherited mutations has been described in several human genetic disorders. Back mutations resulting in restoration of wild-type sequences and second-site mutations leading to compensatory changes have been shown in mosaic individuals. In most cases, however, the precise genetic mechanisms underlying the reversion events have remained unclear, except for the few instances where crossing over or gene conversion have been demonstrated. Here, we report a patient affected with Wiskott–Aldrich syndrome (WAS) caused by a 6-bp insertion (ACGAGG) in the WAS protein gene, which abrogates protein expression. Somatic mosaicism was documented in this patient whose majority of T lymphocytes expressed nearly normal levels of WAS protein. These lymphocytes were found to lack the deleterious mutation and showed a selective growth advantage in vivo. Analysis of the sequence surrounding the mutation site showed that the 6-bp insertion followed a tandem repeat of the same six nucleotides. These findings strongly suggest that DNA polymerase slippage was the cause of the original germ-line insertion mutation in this family and that the same mechanism was responsible for its deletion in one of the propositus T cell progenitors, thus leading to reversion mosaicism.
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Hypermutation can be defined as an enhancement of the spontaneous mutation rate which the organism uses in certain types of differentiated cells where a high mutation rate is advantageous. At the immunoglobulin loci this process increases the mutation rate > 10(5)-fold over the normal, spontaneous rate. Its proximate cause is called the immunoglobulin mutator system. The most important function of this system is to improve antibody affinity in an ongoing response; it is turned on and off during the differentiation of B lymphocytes. We have established an in vitro system to study hypermutation by transfecting a rearranged mu gene into a cell line in which an immunoglobulin mutator has been demonstrated. A construct containing the mu gene and the 3' kappa enhancer has all the cis-acting elements necessary for hypermutation of the endogenous gene segments encoding the variable region. The activity of the mutator does not seem to depend strongly on the position of the transfected gene in the genome. The mutator is not active in transformed cells of a later differentiation stage. It is also not active on a transfected lacZ gene. These results are consistent with the specificity of the mutator system being maintained and make it possible to delineate cis and trans mutator elements in vitro. Surprisingly, the mutator preferentially targets G-C base pairs. Two hypotheses are discussed: (i) the immunoglobulin mutator system in mammals consists of several mutators, of which the mutator described here is only one; or (ii) the primary specificity of the system is biased toward mutation of G-C base pairs, but this specificity is obscured by antigenic selection.
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Beckwith-Wiedemann syndrome (BWS) involves fetal overgrowth and predisposition to a wide variety of embryonal tumors of childhood. We have previously found that BWS is genetically linked to 11p15 and that this same band shows loss of heterozygosity in the types of tumors to which children with BWS are susceptible. However, 11p15 contains > 20 megabases, and therefore, the BWS and tumor suppressor genes could be distinct. To determine the precise physical relationship between these loci, we isolated yeast artificial chromosomes, and cosmid libraries from them, within the region of loss of heterozygosity in embryonal tumors. Five germ-line balanced chromosomal rearrangement breakpoint sites from BWS patients, as well as a balanced chromosomal translocation breakpoint from a rhabdoid tumor, were isolated within a 295- to 320-kb cluster defined by a complete cosmid contig crossing these breakpoints. This breakpoint cluster terminated approximately 100 kb centromeric to the imprinted gene IGF2 and 100 kb telomeric to p57KIP2, an inhibitor of cyclin-dependent kinases, and was located within subchromosomal transferable fragments that suppressed the growth of embryonal tumor cells in genetic complementation experiments. We have identified 11 transcribed sequences in this BWS/tumor suppressor coincident region, one of which corresponded to p57KIP2. However, three additional BWS breakpoints were > 4 megabases centromeric to the other five breakpoints and were excluded from the tumor suppressor region defined by subchromosomal transferable fragments. Thus, multiple genetic loci define BWS and tumor suppression on 11p15.
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SUMMARY The Porcine Reproductive and Respiratory Syndrome (PRRS) virus is one of the most spread pathogens in swine herds all over the world and responsible for a reproductive and respiratory syndrome that causes severe heath and economical problems. This virus emerged in late 1980’s but although about 30 years have passed by, the knowledge about some essential facets related to the features of the virus (pathogenesis, immune response, and epidemiology) seems to be still incomplete. Taking into account that the development of modern vaccines is based on how innate and acquire immunity react, a more and more thorough knowledge on the immune system is needed, in terms of molecular modulation/regulation of the inflammatory and immune response upon PRRSV infection. The present doctoral thesis, which is divided into 3 different studies, is aimed to increase the knowledge about the interaction between the immune system and the PRRS virus upon natural infection. The objective of the first study entitled “Coordinated immune response of memory and cytotoxic T cells together with IFN-γ secreting cells after porcine reproductive and respiratory syndrome virus (PRRSV) natural infection in conventional pigs” was to evaluate the activation and modulation of the immune response in pigs naturally infected by PRRSV compared to an uninfected control group. The course of viremia was evaluated by PCR, the antibody titres by ELISA, the number of IFN-γ secreting cells (IFN- SC) by an ELISPOT assay and the immunophenotyping of some lymphocyte subsets (cytotoxic cells, memory T lymphocytes and cytotoxic T lymphocytes) by flow cytometry. The results showed that the activation of the cell-mediated immune response against PRRSV is delayed upon infection and that however the levels of IFN-γ SC and lymphocyte subsets subsequently increase over time. Furthermore, it was observed that the course of the different immune cell subsets is time-associated with the levels of PRRSV-specific IFN-γ SC and this can be interpreted based on the functional role that such lymphocyte subsets could have in the specific production/secretion of the immunostimulatory cytokine IFN-γ. In addition, these data support the hypothesis that the age of the animals upon the onset of infection or the diverse immunobiological features of the field isolate, as typically hypothesized during PRRSV infection, are critical conditions able to influence the qualitative and quantitative course of the cell-mediated immune response during PRRSV natural infection. The second study entitled “Immune response to PCV2 vaccination in PRRSV viremic piglets” was aimed to evaluate whether PRRSV could interfere with the activation of the immune response to PCV2 vaccination in pigs. In this trial, 200 pigs were divided into 2 groups: PCV2-vaccinated (at 4 weeks of age) and PCV2-unvaccinated (control group). Some piglets of both groups got infected by PRRSV, as determined by PRRSV viremia detection, so that 4 groups were defined as follows: PCV2 vaccinated - PRRSV viremic PCV2 vaccinated - PRRSV non viremic PCV2 unvaccinated - PRRSV viremic PCV2 unvaccinated - PRRSV non viremic The following parameters were evaluated in the 4 groups: number of PCV2-specific IFN-γ secreting cells, antibody titres by ELISA and IPMA. Based on the immunological data analysis, it can be deduced that: 1) The low levels of antibodies against PCV2 in the PCV2-vaccinated – PRRSV-viremic group at vaccination (4 weeks of age) could be related to a reduced colostrum intake influenced by PRRSV viremia. 2) Independently of the viremia status, serological data of the PCV2-vaccinated group by ELISA and IPMA does not show statistically different differences. Consequently, it can be be stated that, under the conditions of the study, PRRSV does not interfere with the antibody response induced by the PCV2 vaccine. 3) The cell-mediated immune response in terms of number of PCV2-specific IFN-γ secreting cells in the PCV2-vaccinated – PRRSV-viremic group seems to be compromised, as demonstrated by the reduction of the number of IFN-γ secreting cells after PCV2 vaccination, compared to the PCV2-vaccinated – PRRSV-non-viremic group. The data highlight and further support the inhibitory role of PRRSV on the development and activation of the immune response and highlight how a natural infection at early age can negatively influence the immune response to other pathogens/antigens. The third study entitled “Phenotypic modulation of porcine CD14+ monocytes, natural killer/natural killer T cells and CD8αβ+ T cell subsets by an antibody-derived killer peptide (KP)” was aimed to determine whether and how the killer peptide (KP) could modulate the immune response in terms of activation of specific lymphocyte subsets. This is a preliminary approach also aimed to subsequently evaluate such KP with a potential antivural role or as adjuvant. In this work, pig peripheral blood mononuclear cells (PBMC) were stimulated with three KP concentrations (10, 20 and 40 g/ml) for three time points (24, 48 and 72 hours). TIME POINTS (hours) KP CONCENTRATIONS (g/ml) 24 0-10-20-40 48 0-10-20-40 72 0-10-20-40 By using flow cytometry, the qualitative and quantitative modulation of the following immune subsets was evaluated upon KP stimulation: monocytes, natural killer (NK) cells, natural killer T (NKT) cells, and CD4+ and CD8α/β+ T lymphocyte subsets. Based on the data, it can be deduced that: 1) KP promotes a dose-dependent activation of monocytes, particularly after 24 hours of stimulation, by inducing a monocyte phenotypic and maturation shift mainly involved in sustaining the innate/inflammatory response. 2) KP induces a strong dose-dependent modulation of NK and NKT cells, characterized by an intense increase of the NKT cell fraction compared to NK cells, both subsets involved in the antibody-dependent cell cytotoxicity (ADCC). The increase is observed especially after 24 hours of stimulation. 3) KP promotes a significant activation of the cytotoxic T lymphocyte subset (CTL). 4) KP can modulate both the T helper and T cytotoxic phenotype, by inducing T helper cells to acquire the CD8α thus becoming doube positive cells (CD4+CD8+) and by inducing CTL (CD4-CD8+high) to acquire the double positive phenotype (CD4+CD8α+high). Therefore, KP may induce several effects on different immune cell subsets. For this reason, further research is needed aimed at characterizing each “effect” of KP and thus identifying the best use of the decapeptide for vaccination practice, therapeutic purposes or as vaccine adjuvant. RIASSUNTO Il virus della PRRS (Porcine Reproductive Respiratory Syndrome) è uno dei più diffusi agenti patogeni negli allevamenti suini di tutto il mondo, responsabile di una sindrome riproduttiva e respiratoria causa di gravi danni ad impatto sanitario ed economico. Questo virus è emerso attorno alla fine degli anni ’80 ma nonostante siano passati circa una trentina di anni, le conoscenze su alcuni punti essenziali che riguardano le caratteristiche del virus (patogenesi, risposta immunitaria, epidemiologia) appaiono ancora spesso incomplete. Considerando che lo sviluppo dei vaccini moderni è basato sui principi dell’immunità innata e acquisita è essenziale una sempre più completa conoscenza del sistema immunitario inteso come modulazione/regolazione molecolare della risposta infiammatoria e immunitaria in corso di tale infezione. Questo lavoro di tesi, suddiviso in tre diversi studi, ha l’intento di contribuire all’aumento delle informazioni riguardo l’interazione del sistema immunitario, con il virus della PRRS in condizioni di infezione naturale. L’obbiettivo del primo studio, intitolato “Associazione di cellule memoria, cellule citotossiche e cellule secernenti IFN- nella risposta immunitaria in corso di infezione naturale da Virus della Sindrome Riproduttiva e Respiratoria del Suino (PRRSV)” è stato di valutare l’attivazione e la modulazione della risposta immunitaria in suini naturalmente infetti da PRRSV rispetto ad un gruppo controllo non infetto. I parametri valutati sono stati la viremia mediante PCR, il titolo anticorpale mediante ELISA, il numero di cellule secernenti IFN- (IFN- SC) mediante tecnica ELISPOT e la fenotipizzazione di alcune sottopopolazioni linfocitarie (Cellule citotossiche, linfociti T memoria e linfociti T citotossici) mediante citofluorimetria a flusso. Dai risultati ottenuti è stato possibile osservare che l’attivazione della risposta immunitaria cellulo-mediata verso PRRSV appare ritardata durante l’infezione e che l’andamento, in termini di IFN- SC e dei cambiamenti delle sottopopolazioni linfocitarie, mostra comunque degli incrementi seppur successivi nel tempo. E’ stato inoltre osservato che gli andamenti delle diverse sottopopolazioni immunitarie cellulari appaiono temporalmente associati ai livelli di IFN- SC PRRSV-specifiche e ciò potrebbe essere interpretato sulla base del ruolo funzionale che tali sottopopolazioni linfocitarie potrebbero avere nella produzione/secrezione specifica della citochina immunoattivatrice IFN-. Questi dati inoltre supportano l’ipotesi che l’età degli animali alla comparsa dell’infezione o, come tipicamente ipotizzato nell’infezione da PRRSV, le differenti caratteristiche immunobiologiche dell’isolato di campo, sia condizioni critiche nell’ influenzare l’andamento qualitativo e quantitativo della risposta cellulo-mediata durante l’infezione naturale da PRRSV. Il secondo studio, dal titolo “Valutazione della risposta immunitaria nei confronti di una vaccinazione contro PCV2 in suini riscontrati PRRSV viremici e non viremici alla vaccinazione” ha avuto lo scopo di valutare se il virus della PRRS potesse andare ad interferire sull’attivazione della risposta immunitaria indotta da vaccinazione contro PCV2 nel suino. In questo lavoro sono stati arruolati 200 animali divisi in due gruppi, PCV2 Vaccinato (a 4 settimane di età) e PCV2 Non Vaccinato (controllo negativo). Alcuni suinetti di entrambi i gruppi, si sono naturalmente infettati con PRRSV, come determinato con l’analisi della viremia da PRRSV, per cui è stato possibile creare quattro sottogruppi, rispettivamente: PCV2 vaccinato - PRRSV viremico PCV2 vaccinato - PRRSV non viremico PCV2 non vaccinato - PRRSV viremico PCV2 non vaccinato - PRRSV non viremico Su questi quattro sottogruppi sono stati valutati i seguenti parametri: numero di cellule secernenti IFN- PCV2 specifiche, ed i titoli anticorpali mediante tecniche ELISA ed IPMA. Dall’analisi dei dati immunologici derivati dalle suddette tecniche è stato possibile dedurre che: I bassi valori anticorpali nei confronti di PCV2 del gruppo Vaccinato PCV2-PRRSV viremico già al periodo della vaccinazione (4 settimane di età) potrebbero essere messi in relazione ad una ridotta assunzione di colostro legata allo stato di viremia da PRRSV Indipendentemente dallo stato viremico, i dati sierologici del gruppo vaccinato PCV2 provenienti sia da ELISA sia da IPMA non mostrano differenze statisticamente significative. Di conseguenza è possibile affermare che in questo caso PRRSV non interferisce con la risposta anticorpale promossa dal vaccino PCV2. La risposta immunitaria cellulo-mediata, intesa come numero di cellule secernenti IFN- PCV2 specifiche nel gruppo PCV2 vaccinato PRRS viremico sembra essere compromessa, come viene infatti dimostrato dalla diminuzione del numero di cellule secernenti IFN- dopo la vaccinazione contro PCV2, comparata con il gruppo PCV2 vaccinato- non viremico. I dati evidenziano ed ulteriormente sostengono il ruolo inibitorio del virus della PRRSV sullo sviluppo ed attivazione della risposta immunitaria e come un infezione naturale ad età precoci possa influenzare negativamente la risposta immunitaria ad altri patogeni/antigeni. Il terzo studio, intitolato “Modulazione fenotipica di: monociti CD14+, cellule natural killer (NK), T natural killer (NKT) e sottopopolazioni linfocitarie T CD4+ e CD8+ durante stimolazione con killer peptide (KP) nella specie suina” ha avuto come scopo quello di stabilire se e come il Peptide Killer (KP) potesse modulare la risposta immunitaria in termini di attivazione di specifiche sottopopolazioni linfocitarie. Si tratta di un approccio preliminare anche ai fini di successivamente valutare tale KP in un potenziale ruolo antivirale o come adiuvante. In questo lavoro, periferal blood mononuclear cells (PBMC) suine sono state stimolate con KP a tre diverse concentrazioni (10, 20 e 40 g/ml) per tre diversi tempi (24, 48 e 72 ore). TEMPI DI STIMOLAZIONE (ore) CONCENTRAZIONE DI KP (g/ml) 24 0-10-20-40 48 0-10-20-40 72 0-10-20-40 Mediante la citometria a flusso è stato dunque possibile analizzare il comportamento qualitativo e quantitativo di alcune sottopopolazioni linfocitarie sotto lo stimolo del KP, tra cui: monociti, cellule Natural Killer (NK), cellule T Natural Killer (NKT) e linfociti T CD4 e CD8+. Dai dati ottenuti è stato possibile dedurre che: 1) KP promuove un’attivazione dei monociti dose-dipendente in particolare dopo 24 ore di stimolazione, inducendo uno “shift” fenotipico e di maturazione monocitaria maggiormente coinvolto nel sostegno della risposta innata/infiammatoria. 2) KP induce una forte modulazione dose-dipendente di cellule NK e NKT con un forte aumento della frazione delle cellule NKT rispetto alle NK, sottopopolazioni entrambe coinvolte nella citotossicità cellulare mediata da anticorpi (ADCC). L’aumento è riscontrabile soprattutto dopo 24 ore di stimolazione. 3) KP promuove una significativa attivazione della sottopopolazione del linfociti T citotossici (CTL). 4) Per quanto riguarda la marcatura CD4+/CD8+ è stato dimostrato che KP ha la capacità di modulare sia il fenotipo T helper che T citotossico, inducendo le cellule T helper ad acquisire CD8 diventando quindi doppio positive (CD4+CD8+) ed inducendo il fenotipo CTL (CD4-CD8+high) ad acquisire il fenotipo doppio positivo (CD4+CD8α+high). Molti dunque potrebbero essere gli effetti che il decapeptide KP potrebbe esercitare sulle diverse sottopopolazioni del sistema immunitario, per questo motivo va evidenziata la necessità di impostare e attuare nuove ricerche che portino alla caratterizzazione di ciascuna “abilità” di KP e che conducano successivamente alla scoperta del migliore utilizzo che si possa fare del decapeptide sia dal punto di vista vaccinale, terapeutico oppure sotto forma di adiuvante vaccinale.
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Este trabalho concentra-se na preparação e caracterizações estrutural e espectroscópica de materiais nanoestruturados à base de SiO2-Nb2O5 dopados e codopados com íons Er3+, Yb3+ e Eu3+ na forma de pós e guias de onda planares. Os nanocompósitos foram preparados através de uma nova rota sol-gel utilizando óxido de nióbio como precursor em substituição ao alcóxido de nióbio. A correlação estrutura propriedades luminescentes foi estudada por difração de raios X, microscopia eletrônica de transmissão, espectroscopia vibracional de absorção no infravermelho, espectroscopia vibracional de espalhamento Raman, análise térmica, reflectância difusa e especular, espectroscopia de fotoluminescência e acoplamento M-line. Inicialmente foi avaliado a influência da concentração de nióbio nas propriedades estruturais e luminescentes de nanocompósitos (100-x)Si-xNb dopados e codopados com íons Er3+, Yb3+ e Eu3+ tratados termicamente a 900 °C por 3h. A cristalização do Nb2O5 foi dependente da concentração de Nb na matriz, com a distribuição dos íons lantanídeos preferencialmente no Nb2O5, afetando as propriedades luminescentes. Para os nanocompósitos codopados com íons Er3+ e Yb3+ foram obtidos valores de largura de banda a meia altura (FWHM) da ordem de 70 nm na região de 1550 nm e tempos de vida de até 5,2 ms. A emissão na região do visível, decorrente de processos de conversão ascendente, revelou-se dependente da concentração de nióbio. Foi verificada emissão preferencial na região do verde para menores concentrações de Nb. Enquanto que, para as maiores concentrações, processos de relaxação cruzada levaram a um aumento relativo na intensidade de emissão na região do vermelho. A eficiência quântica de emissão dos nanocompósitos (100-x)Si-xNb dopados com Eu3+ variou com o comprimento de onda de excitação, refletindo os diferentes sítios de simetria ocupados por este íons nesta estrutura complexa. A influência da temperatura de tratamento térmico no processo de cristalização do Nb2O5 em nanocompósitos 70Si:30Nb codopados com íons Er3+ e Yb3+ foi avaliada. Material amorfo foi obtido a 700 °C enquanto que a 900 e 1100 °C foram identificas as fases ortorrômbica (fase T) e monoclínica (fase M) do Nb2O5. Intensa emissão na região de 1550 nm com valores de FWHM de 52 e 67 nm e tempos de vida de 5,6 e 5,4 ms foram verificados a 700 e 900 °C sob excitação em 977 nm, respectivamente. Por fim, foram obtidos guias de onda planares com excelentes propriedades ópticas e com grande potencial de aplicação em dispositivos de amplificação óptica. Especificamente, materiais fotônicos com banda larga de emissão na região do infravermelho foram preparados, indicando fortemente a potencialidade para a aplicação em telecomunicações envolvendo não somente a banda C como também as bandas L e S em materiais contendo somente íons Er3+ como centros emissores.
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O objetivo deste trabalho é analisar o impacto dos Sistemas de Gestão Integrados (SGI) no desempenho organizacional sob a óptica do Triple Bottom Line (TBL), verificando se esta implementação auxilia a empresa a se tornar mais sustentável. A abordagem multi-método utilizada está dividida em três partes. A primeira compreende uma revisão sistemática da literatura, tendo como base a abordagem bibliométrica. A base de dados escolhida para a seleção dos artigos que compõem a amostra foi a ISI Web of Knowledge (Web of Science). As análises conduzidas sugerem lacunas na literatura a serem pesquisadas de modo a relacionar a integração dos sistemas de gestão como meio para as organizações tornarem-se mais sustentáveis, auxiliando assim na elaboração de um modelo teórico e das hipóteses de pesquisa. Os resultados parciais obtidos ressaltam a lacuna na literatura de estudos nessa área, principalmente que contemplem a dimensão social do Triple Bottom Line. Lacunas na literatura foram identificadas também no que se refere à análise do impacto da adoção dessas abordagens normativas no desempenho organizacional. A segunda etapa da metodologia é composta por estudos de casos múltiplos em empresas de diferentes setores e que tenham implantado sistemas de gestão de maneira integrada. Os resultados obtidos mostram que a certificação auxilia no desenvolvimento de ações sustentáveis, resultando em impactos econômicos, ambientais e sociais positivos. Nesta etapa, testou-se o modelo e as hipóteses levantadas na abordagem bibliométrica. A terceira etapa da metodologia é composta por análises estatísticas de dados secundários extraídos da revista Exame ?Maiores e Melhores\'. Os dados do ano de 2014 das empresas foram tratados por meio do software MINITAB 17 ®. Por meio do teste de mediana de mood, as amostras foram testadas e apresentaram diferenças estatisticamente significativas para o desempenho das empresas em diferentes setores. De maneira geral, as empresas com SGI apresentam melhor desempenho econômico do que as demais. Com a mesma base de dados, utilizando o modelo de equações estruturais e o software Smart PLS 2.0, criou-se um diagrama de caminhos analisando os constructos (SGI) com variáveis de desempenho (Endividamento, Lucratividade, Patrimônio, Crescimento e Retorno). O modelo de equações estruturais testado apresentou força para a relação entre SGI com Endividamento, Lucratividade, Patrimônio e Crescimento. As diferentes metodologias apresentadas contribuíram para responder a hipótese e afirmar com base na amostra deste trabalho que o SGI leva as empresas a terem melhor desempenho econômico, ambiental e social (baseado no TBL).
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"April 1996."
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Propofol infusion syndrome (PRIS) is a rare but often fatal complication as a result of large doses of propofol infusion (4–5 mg/kg/hr) for a prolonged period (>48 h). It has been reported in both children and adults. Besides large doses of propofol infusion, the risk factors include young age, acute neurological injury, low carbohydrate and high fat intake, exogenous administration of corticosteroid and catecholamine, critical illness, and inborn errors of mitochondrial fatty acid oxidation. PRIS manifestation include presence of metabolic acidosis with a base deficit of more than 10 mmol/l at least on one occasion, rhabdomyolysis or myoglobinuria, acute renal failure, sudden onset of bradycardia resistant to treatment, myocardial failure, and lipemic plasma. The pathophysiology of PRIS may be either direct mitochondrial respiratory chain inhibition or impaired mitochondrial fatty acid metabolism mediated by propofol. We report a case of supermorbidly obese patient who received propofol infusion by total body weight instead of actual body weight and developed PRIS.
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Cultured human choriocarcinoma cells of the BeWo line exhibited saturable accumulation of radioiodide. Inhibition by competing anions followed the affinity series perchlorate >= iodide >= thiocyanate, consistent with uptake through the thyroid iodide transporter, NIS, whose messenger RNA was found in BeWo cells, and whose protein was distributed towards the apical pole of the cells. Efflux obeyed first order kinetics and was inhibited by DIDS, an antagonist of anion exchangers including pendrin, whose messenger RNA was also present. In cultures where iodide uptake through NIS was blocked with excess perchlorate, radiolodide accumulation was stimulated by exposure to medium in which physiological anions were replaced by 2-morpholinoethanesulfonic acid (MES), consistent with the operation of an anion exchange mechanism taking up iodide. Chloride in the medium was more effective than sulfate at inhibiting this uptake, matching the ionic specificity of pendrin. These studies provide evidence that the trophoblast accumulates iodide through NIS and releases it to the fetal compartment through pendrin. (c) 2004 Elsevier Ltd. All rights reserved.