999 resultados para Ubiquitination en N-terminal


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Describe la identificación de tres focos principales de contaminación del Puerto de Callao, los mismos que están vinculados a: 1.- aguas provenientes del río Rímac; 2.- aguas de la rada interior del puerto, por la lenta remoción de las aguas, a las actividades del puerto y derrame ocasionales de petróleo, desechos industriales del SIMA y desechos del terminal pesquero; 3.- el área frente al muelle de guerra Camotal, donde la contaminación es principalmente por descarga de desechos de los buques y derrame de petróleo debido al transporte de estos y a las descargas periódicas de los restaurantes ubicados en el litoral.

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We previously reported that interleukin-1beta (IL-1beta) alone does not cause apoptosis of beta-cells, whereas when combined with gamma-interferon (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha), it exerts a distinct apoptotic effect. Studies in beta-cell lines indicated that IL-1beta reduced expression of islet brain (IB)-1/JNK interacting protein (JIP)-1, a JNK scaffold protein with antiapoptotic action. We examined whether variations in IB1/JIP-1 expression in purified primary beta-cells affect their susceptibility to cytokine-induced apoptosis. Exposure to IL-1beta for 24 h decreased cellular IB1/JIP-1 content by 66 +/- 17%; this IL-1beta effect was maintained in the presence of TNF-alpha + IFN-gamma, which did not influence IB1/JIP-1 levels by themselves. Addition of IL-1beta to TNF-alpha + IFN-gamma increased apoptosis from 20 +/- 2% to 59 +/- 5%. A similar increase in TNF-alpha + IFN-gamma-induced apoptosis was produced by adenoviral expression of antisense IB1/JIP-1 and was not further enhanced by addition of IL-1beta, indicating that IL-1beta-mediated suppression of IB1/JIP-1 in beta-cells increases their susceptibility to cytokine-induced apoptosis. However, adenovirally mediated overexpression of IB1/JIP-1 also potentiated TNF-alpha + IFN-gamma-induced apoptosis, suggesting that the antiapoptotic effect of IB1/JIP-1 depends on well-defined cellular levels. We conclude that the IB1/JIP-1 level in beta-cells can control their susceptibility to apoptosis independent of JNK signaling.

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A fast and reliable assay for the identification of dermatophyte fungi and nondermatophyte fungi (NDF) in onychomycosis is essential, since NDF are especially difficult to cure using standard treatment. Diagnosis is usually based on both direct microscopic examination of nail scrapings and macroscopic and microscopic identification of the infectious fungus in culture assays. In the last decade, PCR assays have been developed for the direct detection of fungi in nail samples. In this study, we describe a PCR-terminal restriction fragment length polymorphism (TRFLP) assay to directly and routinely identify the infecting fungi in nails. Fungal DNA was easily extracted using a commercial kit after dissolving nail fragments in an Na(2)S solution. Trichophyton spp., as well as 12 NDF, could be unambiguously identified by the specific restriction fragment size of 5'-end-labeled amplified 28S DNA. This assay enables the distinction of different fungal infectious agents and their identification in mixed infections. Infectious agents could be identified in 74% (162/219) of cases in which the culture results were negative. The PCR-TRFLP assay described here is simple and reliable. Furthermore, it has the possibility to be automated and thus routinely applied to the rapid diagnosis of a large number of clinical specimens in dermatology laboratories.

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Background: In intracerebral hemorrhage (ICH), a subtype of stroke, the bloodentry into the brain triggers toxicity resulting in a strong loss of neurons andinflammation. Water content is also increases leading to growing intracranial pressure,which worsens neurological outcome. C-Jun N-terminal kinases (JNKs) areactivated in response to stress stimuli. Specific inhibition of JNK by a TAT-coupledpeptide (XG-102) mediates neuroprotection in several models of ischemic stroke.Recently, we have noted that the JNK pathway is also activated in a mouse modelof ICH, raising the question of the efficacy of XG-102 in this model.Method: ICH was induced in the mouse by intrastriatal injection of bacterialcollagenase (0,1U). Three hours later, animals received an i.v. injection of XG-102(100μg/kg). The neuroscore was assessed using a scale (from 0 to 9) based on 3behavioral tests performed daily. Then, mice were sacrificed at 6h, 24h, 48h and 5dafter ICH and histological studies performed.Results: XG-102 significantly improves neurological outcome at 24h (mean score:1,8±1.4 vs 3,4±1.8, p<0.01). Analysis of the lesion volume revealed a significantdecrease of the lesion area in the treated group at 48h (29±11 mm3 vs 39±5 mm3,p = 0.04). XG-102 mainly inhibits the edema component of the lesion. Indeed, asignificant decrease of the brain swelling was observed in treated animals at 48h(14±13% vs 26±9%, p=0.04) and 5d (-0,3±4.5% vs 5,1±3.6%, p=0.01).Conclusions: Inhibition of the JNK pathway by XG-102 appears to lead to asignificant decrease of the cerebral edema in the ICH model providing a furtherbeneficial effect of the XG-102 treatment. This result is of interest becausecurrently, clinical treatment for brain edema is limited. Importantly, the beneficialeffects observed with XG-102 in both stroke models open the possibility to rapidlytreat patients before identifying the stroke subtype by imaging.

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The Barge Terminal Directory has been prepared by the Iowa Department of Transportation’s Modal Division to provide quick access to information on Iowa’s river terminals and fleeting/harbor services. The information is to assist those who may need barge transportation services. The information in the directory was provided by the terminal operators. The Modal Division would appreciate any help on corrections, additions or deletions.

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La conspiración de silencio (CdS) es un fenómeno universal que hace referencia a un acuerdo tácito entre profesionales y familiares/cuidadores para ocultar información al paciente, relacionada con su situación clínica, sin considerar las necesidades de información del mismo. En circunstancias de enfermedad terminal, la ocultación del diagnóstico, pronóstico u objetivo de tratamiento no sólo tiene implicaciones éticas, sino que influye en la práctica asistencial. Las consecuencias de la CdS se producen tanto en el paciente, como en la familia, en los profesionales y en el propio sistema sanitario, siendo la barrera comunicativa que se establece, una de las mayores repercusiones negativas que afecta a todos los individuos implicados. La CdS impide al paciente la preparación para su próxima muerte. Los profesionales ante estas circunstancias, no pueden ofrecer cuidados óptimos debido a la imposibilidad de explorar aspectos emocionales en el paciente relacionados con la cercanía de la muerte. Estos aspectos adquieren una importancia esencial en cuidados de final de vida donde la comunicación efectiva es el vehículo primordial. La cantidad y calidad de información que reciben los pacientes está determinada por aspectos sociales, personales, psicológicos y culturales donde los profesionales de la salud son los principales implicados como parte integrante del proceso informativo. Es necesario hacer un análisis de los factores que precipitan la CdS, sus posibles repercusiones y los beneficios potenciales que conlleva la transmisión de malas noticias para lograr una comprensión del fenómeno. Es indudable que los médicos y enfermeras, a través de sus actitudes, pueden influir en la aparición o mantenimiento de este fenómeno, y que un buen conocimiento del mismo puede contribuir a su futuro manejo. Dada la importancia del tema en la práctica clínica, el presente estudio pretende clarificar el fenómeno y analizar las actitudes de los profesionales de la salud ante la CdS. El explorarlo es una tarea compleja ocasionada por la ausencia de instrumentos válidos y fiables para su cuantificación y análisis. Por este motivo uno de los objetivos centrales de este estudio es la elaboración de una escala que permita evaluar las actitudes de los profesionales ante la CdS en pacientes paliativos.

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Epithelial to Mesenchymal Transition (EMT) in cancer is a process that allows cancer cells to detach from neighboring cells, become mobile and metastasize and shares many signaling pathways with development. Several molecular mechanisms which regulate oncogenic properties in neoplastic cells such as proliferation, resistance to apoptosis and angiogenesis through transcription factors or other mediators are also regulators of EMT. These pathways and downstream transcription factors are, in their turn, regulated by ubiquitination and the Ubiquitin-Proteasome System (UPS). Ubiquitination, the covalent link of the small 76-amino acid protein ubiquitin to target proteins, serves as a signal for protein degradation by the proteasome or for other outcomes such as endocytosis, degradation by the lysosome or directing these proteins to specific cellular compartments. This review discusses aspects of the regulation of EMT by ubiquitination and the UPS and underlines its complexity focusing on transcription and transcription factors regulating EMT and are being regulated by ubiquitination.

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Abstract Purpose: XG-102, a TAT-coupled dextrogyre peptide inhibiting the c-Jun N-terminal kinase, was shown efficient in the treatment of experimental uveitis. Preclinical studies are now performed to determine optimal XG-102 dose and route of administration in endotoxin-induced uveitis (EIU) in rats with the purpose of clinical study design. METHODS: EIU was induced in Lewis rats by lipopolysaccharides (LPS) injection. XG-102 was administered at the time of LPS challenge by intravenous (IV; 3.2, 35 or 355 μg/injection), intravitreal (IVT; 0.08, 0.2 or 2.2 μg/eye), or subconjunctival (SCJ; 0.2, 1.8 or 22 μg/eye) routes. Controls received either the vehicle (saline) or dexamethasone phosphate injections. Efficacy was assessed by clinical scoring, infiltrating cells count, and expression of inflammatory mediators [inducible nitric oxide synthase (iNOS), cytokine-induced neutrophil chemoattractant-1 (CINC-1)]. The effect of XG-102 on phosphorylation of c-Jun was evaluated by Western blot. RESULTS: XG-102 demonstrated a dose-dependent anti-inflammatory effect in EIU after IV and SCJ administrations. Respective doses of 35 and 1.8 μg were efficient as compared with the vehicle-injected controls, but only the highest doses, respectively 355 and 22 μg, were as efficient as dexamethasone phosphate. After IVT injections, the anti-inflammatory effect of XG-102 was clinically evaluated similar to the corticoid's effect with all the tested doses. Regardless of the administration route, the lowest efficient doses of XG-102 significantly decreased the ration of phospho c-Jun/total c-Jun, reduced cells infiltration in the treated eyes, and significantly downregulated iNOS and CINC-1 expression in the retina. CONCLUSION: These results confirm that XG-102 peptide has potential for treating intraocular inflammation. SCJ injection appears as a good compromise to provide a therapeutic effect while limiting side effects.

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The proteasome produces MHC class I-restricted antigenic peptides carrying N-terminal extensions, which are trimmed by other peptidases in the cytosol or within the endoplasmic reticulum. In this study, we show that the N-terminal editing of an antigenic peptide with a predicted low TAP affinity can occur in the cytosol. Using proteomics, we identified two cytosolic peptidases, tripeptidyl peptidase II and puromycin-sensitive aminopeptidase, that trimmed the N-terminal extensions of the precursors produced by the proteasome, and led to a transient enrichment of the final antigenic peptide. These peptidases acted either sequentially or redundantly, depending on the extension remaining at the N terminus of the peptides released from the proteasome. Inhibition of these peptidases abolished the CTL-mediated recognition of Ag-expressing cells. Although we observed some proteolytic activity in fractions enriched in endoplasmic reticulum, it could not compensate for the loss of tripeptidyl peptidase II/puromycin-sensitive aminopeptidase activities.

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La mort i el procés de morir són fets quotidians en les persones grans i, conseqüentment, en els centres sociosanitaris, on bona part de les persones usuàries són d’edat avançada. Tot i que es tracta d’un fenomen natural que s’inclou dins del cicle vital de les persones, en la nostra societat la mort encara provoca rebuig, por, ansietat, tristesa i inquietud. En aquest marc, les estudiants1 d’infermeria són un col·lectiu que poden patir especialment l’impacte de la mort. Primer, perquè com a membres de la societat tenen interioritzat el codi social preestablert envers aquest tema i, segon, perquè durant la seva formació estan en contacte amb persones que estan al final de la vida i poden presenciar vivències de mort. En el primer període de pràctiques dels estudis d’infermeria, les estudiants han de fer front a diverses situacions del dia a dia fins aleshores desconegudes. Els conflictes interpersonals amb l'equip de treball i la inseguretat sobre les habilitats i les competències professionals són alguns dels aspectes que acostumen a viure amb més tensió. Tot i això, el que més impacte els provoca és la cura de les persones al final de la vida. Davant d'una situació de tensió, la persona viu un component estressor, que suposa el punt d’inflexió. A partir d’aquí s’activen els components adaptatius, que és el que emocionalment fa que la persona pugui fer front a aquesta situació estressant. A més, hi ha un component de suport, que són les ajudes que té. Segons com es treballi el component adaptatiu farà que la persona reaccioni en un futur de forma més automàtica i inconscient o, al contrari, que la persona respongui de forma més conscient i intencionada. El present treball està concebut per comprendre quins elements psicosocials – components estressors i components de suport– poden afectar a les estudiants que presencien la vivència de la mort de malalts geriàtrics terminals en el primer període de pràctiques en un centre sociosanitari. S’ha dissenyat un estudi descriptiu transversal quantitatiu, de caràcter exploratori, per tal de descriure la freqüència i algunes característiques psicosocials al voltant de la mort en estudiants d'infermeria en el seu primer període de pràctiques, tant a nivell personal com a nivell professional. La mostra de l'estudi són 65 estudiants, la majoria són dones d'entre els 18 i els 29 anys –més d’un 90%–. Els resultats indiquen que un 80% dels futurs professionals estudiats han patit la mort d’alguna persona significativa al llarg de la seva vida; d'aquests, gairebé un de cada quatre presenta dol complicat. Quant a la vivència de mort en les pràctiques, el 83% l'ha experimentat. Tot i aquest elevat percentatge, no totes les experiències tenen una connotació negativa. En prop de la meitat dels casos, les morts són percebudes com una experiència enriquidora i natural. Els components estressors més impactants que les estudiants han viscut durant les pràctiques per la mort d’alguna persona malalta són: la reacció de la família del finat, el patiment que es genera al seu voltant, algun signe o símptoma físic experimentat pel malalt al final del procés, i la pròpia reacció emocional. Els components de suport expressats són: saber gestionar les pròpies emocions, tenir més formació sobre relació d’ ajuda i empatia, tenir més formació en control de símptomes i comunicació, per atendre usuaris –tant malalts com familiars- i que algú els informés i orientés en el procés. Altres resultats a tenir en compte són que la població estudiada té més preocupació o inquietud per la mort i el procés de morir de la persona estimada i menys per la pròpia mort. A més, tot i que la meitat no hagués escollit geriatria com opció a les primeres pràctiques clíniques, gairebé tot el grup estudiat ho recomanaria després d'haver viscut l'experiència. Les implicacions pràctiques d'aquest estudi porten a pensar que es pot reorientar la informació i preparació que es dóna a les estudiants d’infermeria abans del primer contacte amb la realitat dels centres sociosanitaris, així com també el paper de formació i suport que pot fer tant la persona tutora de pràctiques com les infermeres de referència dels diferents centres. En conclusió, caldria dissenyar estratègies formatives i de suport entorn a la preparació psicològica personal de l’estudiant; entorn a l’acompanyament, les cures pal·liatives i el dol; i valorar la seva eficiència en el futur.

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Apoptosis of pancreatic beta cells is implicated in the onset of type 1 and type 2 diabetes. Consequently, strategies aimed at increasing the resistance of beta cells toward apoptosis could be beneficial in the treatment of diabetes. RasGAP, a regulator of Ras and Rho GTPases, is an atypical caspase substrate, since it inhibits, rather than favors, apoptosis when it is partially cleaved by caspase-3 at position 455. The antiapoptotic signal generated by the partial processing of RasGAP is mediated by the N-terminal fragment (fragment N) in a Ras-phosphatidylinositol 3-kinase-Akt-dependent, but NF-kappaB-independent, manner. Further cleavage of fragment N at position 157 abrogates its antiapoptotic properties. Here we demonstrate that an uncleavable form of fragment N activates Akt, represses NF-kappaB activity, and protects the conditionally immortalized pancreatic insulinoma betaTC-tet cell line against various insults, including exposure to genotoxins, trophic support withdrawal, and incubation with inflammatory cytokines. Fragment N also induced Akt activity and protection against cytokine-induced apoptosis in primary pancreatic islet cells. Fragment N did not alter insulin cell content and insulin secretion in response to glucose. These data indicate that fragment N protects beta cells without affecting their function. The pathways regulated by fragment N are therefore promising targets for antidiabetogenic therapy.

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En aquest article es descriu la implementacio d'una xarxa de CD-ROM en una biblioteca universitària, així com la integració d'aquesta en una unitat de documentació. Es comenten les característiques de la xarxa,problemes tècnics, llicències de xarxa i aspectes d'ampliació i accés remot. Son especialment destacables els menús, el disseny dels sistemes de control estadístic centralitzat i les possibilitats de connexió des de sistemes VAX-DIGITAL. Un dels aspectes mes importants es la integració electrónica de serveis, que permet, des del mateix terminal i de forma selectiva, accedir a la consulta del catáleg propi i a les utilitats de la xarxa (processadors de textos, gràfics), consultar bases de dades bibliográfiques en CD-ROM o suport magnetic, i disposar d'un subsistema automatitzat d'obtenció de documents per demanar articles, comprovar l'estat de la petició i realitzar amplis controls administratius i estadístics.

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In neurodegenerative diseases, one can observe deposits of degradation products that represent hallmark structures. Actually, the underlying mechanisms are not well understood, but some hypotheses claim that the ubiquitin-proteasome system is perturbed in neurodegenerative diseases. Some of the influencing factors are aging, oxidation and the formation of free radicals, as well as genetic mutations which affect the function of proteins and result in an accumulation and formation of aggresomes. The amyotrophic lateral sclerosis, in which a malfunction of the sodium dismutase perturbs the redox system, is characterized by the accumulation of elements of the cytoskeleton in motor neurons and a progressive neuronal death. We suppose that in these diseases the ubiquitin- proteasome system is deregulated and try to demonstrate this hypothesis by comparing the ubiquitination of different neurofilaments in brain and spinal cord of transgenic and control mice. These NFH-LacZ mice with a truncated NF-H protein and a ß-galactosidase marker protein induce an accumulation of NF-proteins and neurofilaments are no longer transported into axons or dendrites. The accumulation of such aggregates resembles the phenotype of amyotrophic lateral sclerosis. Beside the ubiquitination the neurofilament expression and phosphorylation state was investigated. The results cannot demonstrate a perturbation of the ubiquitin-proteasome system of neurofilaments in transgenic mice. In contrast, in accordance with the mechanism of the NFH-LacZ mice a decrease of high and medium density neurofilaments and a hypophosphorylation were found. In conclusion, to elicit the pathological mechanism of amyotrophic lateral sclerosis and to develop focused treatments, we have to review the pathological mechanism of the transgenic mice and repeat the experiments with other animal models or with human material. Other possibilities would be to focus on other degradation mechanisms, such as the endosome/lysosome system, and to define their role in the amyotrophic lateral sclerosis more clearly.