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1.
Chemosphere ; 220: 892-899, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33395810

RESUMEN

Technosols created to reclaim degraded soils is a promising solution that needs further research. The objectives of the study were: i) to create a Technosol with a very high capacity to immobilize copper from mining, ii) to assess the capacity of the Technosol to immobilize copper after planting two tropical native tree species, and iii) to analyse the capacity of the native trees for extracting copper from polluted soils. Myracrodruon urundeuva (aroeira) and Cedrela fissilis (pink cedar) were planted in pots with Technosol spiked with copper at concentrations of 125, 1525 and 3050 mg Cu kg-1. Height and stem diameter were measured over 90 days. Biomass and Cu concentration in leaves, stem and roots were determined. Copper was analysed in soils by sequential extraction, as well as in leached water. The Technosol showed a very high capacity to immobilize copper, since 60-80% of the added copper was strongly retained in the soil, mainly by bentonite and carbonates. The Technosol with trees showed the same capacity to immobilize copper as the control, since concentration in shoots was higher than 300 mg Cu kg-1 and concentration in roots was even higher. These results show that Technosol and both species are useful tools to immobilize copper in polluted soils. Further studies are necessary to determine the total capacity of these trees to immobilize and/or extract copper in the long term and under field conditions.

2.
Int J Phytoremediation ; 20(14): 1456-1463, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30652533

RESUMEN

Due to the limited number of studies on phytoremediation using native tree species in tropical soils, the aim was to identify new phytoremediator species from tropical climate with the purpose of promoting an increase in the diversity of tropical native trees used in phytoremediation projects. Seven native tree species from Brazil were selected: Cedrela fissilis, Handroanthus serratifolius, Copaifera langsdorffii, Hymenaea courbaril, Mimosa caesalpiniifolia, Cecropia sp. and Myracrodruon urundeuva. Seedlings of these species were planted in pots with an unpolluted Arenosol, and then spiked with 60, 100 and 500 mg kg-1 Cu. Height and stem diameters were measured over 60 days. Biomass and total Cu concentration were determined in leaves, stem and roots. Copper in bulk soils and rhizospheres was analyzed by a sequential extraction method. All species accumulated high concentration of Cu in roots (>300 mg kg-1), so they could be used as phytostabilizators for this metal. Copper mobilization increased in the rhizospheres, but it was mostly absorbed by roots. Cecropia sp., M. urundeuva and C. langsdorffii are hyperaccumulators of Cu (>300 mg kg-1 in shoots), so they are potential phytoextractor species. This study evidence the potential of seven tree species native from tropical regions for phytostabilizing copper-polluted soils.


Asunto(s)
Contaminantes del Suelo , Árboles , Biodegradación Ambiental , Brasil , Cobre , Suelo
3.
Environ Sci Pollut Res Int ; 23(3): 2595-602, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26432263

RESUMEN

One technique applied to restore degraded or contaminated soils is to use amendments made of different types of waste materials, which in turn may contain metals such as Cu, Pb and Zn. For this reason, it is important to determine the capacity of the soil to retain these materials, and to compare the sorption capacity between an amended soil and another unamended soil. The aim of this study was to determine the mobility and availability of these metals in the soil after applying the amendment, and how it affected the soil's sorption capacity. Sorption isotherms were compared with the empirical models of Langmuir and Freundlich to estimate the sorption capacity. The overall capacity of the soils to sorb Cu, Pb or Zn was evaluated as the slope Kr. The amendments used in this study were a mixture made of compost and biochar in different proportions (20, 40, 60, 100 %), which were applied to the mine tailing from a settling pond from a copper mine. The mine tailing that were amended with the mixture of compost and biochar had a higher sorption capacity than the mine tailing from the unamended pond, and their sorption isotherms had a greater affinity towards Cu, Pb and Zn than the mine tailing that was studied. Therefore, the results obtained show that adding a mixture of compost and biochar favours the retention of Cu, Pb and Zn in mine tailing.


Asunto(s)
Carbón Orgánico , Restauración y Remediación Ambiental , Minería , Contaminantes del Suelo , Suelo , Absorción Fisicoquímica , Cobre , Metales , Contaminantes del Suelo/análisis
4.
Cient. dent. (Ed. impr.) ; 12(3): 231-236, sept.-dic. 2015. tab
Artículo en Español | IBECS | ID: ibc-147166

RESUMEN

Los bifosfonatos (BFs) son fármacos que se utilizan en el tratamiento y prevención de enfermedades relacionadas con el metabolismo óseo. En 2003 se observa, por primera vez, una relación entre la osteonecrosis mandibular (ONJ) y la ingesta de BFs, surgiendo así el concepto BRONJ (biphosphonate-related osteonecrosis of the jaw). Recientemente el uso del plasma rico en factores de crecimiento (PRGF) se ha introducido en el mundo de la odontología por su capacidad regeneradora de tejidos blandos; sin embargo, su papel en el proceso de regeneración de lesiones producidas por cirugías odontológicas está aún por determinar. El objetivo de esta revisión radica en evaluar la eficacia del PRGF en la realización de actos quirúrgicos en pacientes con BRONJ (AU)


Biphosphonates are a commonly used class of drug in the treatment and prevention of diseases-related bone turn over. By the first time, in 2003, the relation between biphosphonates consumption and develop of osteonecrosis of the jaw (ONJ) was established, bring into being the concept of biphosphonate-related osteonecrosis of the jaws (BRONJ). Recently, plasma rich in growth factors (PRGF) has been introduced in dentistry procedures by its regenerative soft tissues capacities; however, its paper in regenerative procedures when surgical lesions appear is still unclear (AU)


Asunto(s)
Humanos , Plasma Rico en Plaquetas , Osteonecrosis de los Maxilares Asociada a Difosfonatos/prevención & control , Sustancias Protectoras/farmacocinética , Difosfonatos/efectos adversos , Osteoporosis/tratamiento farmacológico , Procedimientos Quirúrgicos Preprotésicos Orales
5.
Environ Sci Pollut Res Int ; 22(17): 13372-81, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25940484

RESUMEN

The aim of this study was to physically demonstrate the associations between Ni, Pb and Zn and the different soil components. To achieve this, several soil samples were observed by field emission-scanning electron microscope (FE-SEM) equipped with an energy dispersive spectrometer (EDS) detector. The samples came from mine sites vegetated and/or amended with wastes (sewage sludges and paper mill residues). The concentrations of metals in the different soil fractions were quantified by a chemical sequential extraction in a previous study. The sorption capacity of the soils was evaluated with sorption experiments using the batch method. We corroborated the results obtained by the sequential extraction of metals as well as the sorption experiments with the observations from the FE-SEM with the EDS. We physically observed the associations between Ni, Pb and Zn and oxides, organic matter and clays. We also observed PbCaCO3 crystals in one of the soils, presumably formed during the sorption experiment. As it is not possible to know with complete certainty how Pb was retained by calcium in this soil by only using chemical methods, the use of microscopic techniques is crucial to ascertain how metals are associated with the different soil fractions.


Asunto(s)
Plomo/análisis , Níquel/análisis , Contaminantes del Suelo/análisis , Zinc/análisis , Adsorción , Plomo/química , Microscopía Electrónica de Rastreo , Minería , Níquel/química , Aguas del Alcantarillado , Suelo/química , Contaminantes del Suelo/química , Zinc/química
6.
Environ Sci Pollut Res Int ; 21(16): 9689-708, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24819436

RESUMEN

Toxicity profiles of two soils (a brownfield in Legazpi and an abandoned iron mine in Zugaztieta; Basque Country) contaminated with several metals (As, Zn, Pb and Cu in Legazpi; Zn, Pb, Cd and Cu in Zugaztieta) and petroleum hydrocarbons (in Legazpi) were determined using a multi-endpoint bioassay approach. Investigated soils exceeded screening values (SVs) of regulatory policies in force (Basque Country; Europe). Acute and chronic toxicity bioassays were conducted with a selected set of test species (Vibrio fischeri, Dictyostelium discoideum, Lactuca sativa, Raphanus sativus and Eisenia fetida) in combination with chemical analysis of soils and elutriates, as well as with bioaccumulation studies in earthworms. The sensitivity of the test species and the toxicity endpoints varied depending on the soil. It was concluded that whilst Zugaztieta soil showed very little or no toxicity, Legazpi soil was toxic according to almost all the toxicity tests (solid phase Microtox, D. discoideum inhibition of fruiting body formation and developmental cycle solid phase assays, lettuce seed germination and root elongation test, earthworm acute toxicity and reproduction tests, D. discoideum cell viability and replication elutriate assays). Thus, albeit both soils had similar SVs, their ecotoxicological risk, and therefore the need for intervening, was different for each soil as unveiled after toxicity profiling based on multiple endpoint bioassays. Such a toxicity profiling approach is suitable to be applied for scenario-targeted soil risk assessment in those cases where applicable national/regional soil legislation based on SVs demands further toxicity assessment.


Asunto(s)
Oligoquetos/efectos de los fármacos , Petróleo/toxicidad , Contaminantes del Suelo/toxicidad , Aliivibrio fischeri , Animales , Bioensayo , Dictyostelium/efectos de los fármacos , Dictyostelium/crecimiento & desarrollo , Ecotoxicología , Monitoreo del Ambiente , Germinación/efectos de los fármacos , Lactuca/efectos de los fármacos , Lactuca/fisiología , Oligoquetos/fisiología , Petróleo/análisis , Contaminación por Petróleo/análisis , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/fisiología , Raphanus/efectos de los fármacos , Raphanus/fisiología , Medición de Riesgo , Suelo/química , Contaminantes del Suelo/análisis , Pruebas de Toxicidad
7.
Chemosphere ; 95: 511-8, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24182398

RESUMEN

Mine soils are notable for their low organic matter content. Soils in the depleted copper mine in Touro (Galicia, Spain) were vegetated with trees (eucalyptuses and pines) and amended with wastes (sewage sludge and paper mill residues) to increase their carbon concentration. Two different zones at the mine (settling pond and mine tailing) and their respective treated areas (vegetated and/or amended) were sampled and analysed with the aim of evaluating in depth the effect of the reclamation treatments on both the concentration and quality of soil organic matter under field conditions. The results showed that the two treatments (tree vegetation and waste amendment) significantly increased the organic C in the mine soils from 1.4-6.6 to 10-112 g kg(-1). However, only the soil amended with wastes in the settling pond reached the usual values of undisturbed soils (92-126 g TOC kg(-1) soil). Amending with wastes was also the only treatment that increased the soil humified organic C concentration to proper values and therefore also the microbial biomass C. We recommend the use of organic wastes for amending soils poor in organic matter as well as the regular application of this treatment, as the nitrogen supply can be more limiting for plant growth than the organic C.


Asunto(s)
Restauración y Remediación Ambiental/métodos , Minería , Contaminantes del Suelo/análisis , Suelo/química , Biomasa , Carbono/análisis , Nitrógeno/análisis , Desarrollo de la Planta , Aguas del Alcantarillado/análisis , Aguas del Alcantarillado/química , Microbiología del Suelo , Contaminantes del Suelo/química , España , Árboles/crecimiento & desarrollo , Eliminación de Residuos Líquidos
8.
Chemosphere ; 90(2): 603-10, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23026161

RESUMEN

Mine soils are often physically degraded, which hinders plants development. The untreated soils at the depleted copper mine in Touro (Galicia, north-west Spain) have no vegetation and are probably physically degraded. These mine soils were reclaimed both by planting trees and amending with waste (sewage sludge and paper mill residues). The purpose was to determine the effect of these treatments on the physical quality of the soils of the Touro mine under field conditions. We evaluated the physical situation of both the settling pond and the mine tailings in Touro, then comparing them with their respective treated areas: vegetated, amended or with both treatments at the same time. We corroborated that the physical degradation of untreated soils was considerable: low porosity, high density and less than 50% of water stable aggregates. The trees that were planted increased porosity, probably due to root activity. The added amendments increased the mean weight diameter (MWD), the percentage of water stable aggregates (WSA) and the stability index (SI) due to the high organic carbon content in the added wastes. We verified that using both treatments at the same time is better than using only one to improve the physical situation of mine soils.


Asunto(s)
Cobre/análisis , Restauración y Remediación Ambiental/métodos , Minería , Contaminantes del Suelo/análisis , Árboles/crecimiento & desarrollo , Biodegradación Ambiental , Aguas del Alcantarillado , Suelo/química , España , Residuos
9.
Neuroscience ; 162(4): 959-71, 2009 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-19477238

RESUMEN

The accumulation of reactive microglia in the degenerating areas of amyotrophic lateral sclerosis (ALS) tissue is a key cellular event creating a chronic inflammatory environment that results in motoneuron death. We have developed a new culture system that consists in rat spinal cord embryonic explants in which motoneurons migrate outside the explant, growing as a monolayer in the presence of glial cells. The proinflammatory cytokines tumor necrosis factor alpha (TNF-alpha) and interferon gamma (IFN-gamma) have been proposed to be involved in ALS-linked microglial activation. In our explants, the combined exposure to these cytokines resulted in an increased expression of the pro-oxidative enzymes inducible nitric oxide synthase (iNOS), the catalytic subunit of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, gp91(phox) and cyclooxygenase-2 (COX-2), as compared to each cytokine alone. This effect was related to their cooperation in the activation of the transcription factor nuclear factor kappa B (NF-kappaB). TNF-alpha and IFN-gamma also cooperated to promote protein oxidation and nitration, thus increasing the percentage of motoneurons immunoreactive for nitrotyrosine. Apoptotic motoneuron death, measured through annexin V-Cy3 and active caspase-3 immunoreactivities, was also found cooperatively induced by TNF-alpha and IFN-gamma. Interestingly, these cytokines did not affect the viability of purified spinal cord motoneurons in the absence of glial cells. It is proposed that the proinflammatory cytokines TNF-alpha and IFN-gamma have cooperative/complementary roles in inflammation-induced motoneuron death.


Asunto(s)
Interferón gamma/fisiología , Neuronas Motoras/citología , Estrés Oxidativo , Médula Espinal/citología , Factor de Necrosis Tumoral alfa/fisiología , Animales , Apoptosis , Movimiento Celular , Supervivencia Celular , Medios de Cultivo , Embrión de Mamíferos , Interferón gamma/farmacología , Microglía/efectos de los fármacos , Microglía/fisiología , Neuronas Motoras/efectos de los fármacos , Neuronas Motoras/metabolismo , Óxido Nítrico/biosíntesis , Ratas , Ratas Sprague-Dawley , Médula Espinal/efectos de los fármacos , Técnicas de Cultivo de Tejidos , Factor de Necrosis Tumoral alfa/farmacología
10.
Endodoncia (Madr.) ; 26(1): 7-12, ene.-mar. 2008. tab, ilus
Artículo en Español | IBECS | ID: ibc-73964

RESUMEN

Objetivo: Evaluar la extrusión de material y la capacidad de sellado de diferentes diámetros de thermafilen conductos con una misma preparación (diámetro y conicidad). Material y métodos: 60 dientes unirradiculares fueron obturados, 30 dientes con el mismo diámetro de la preparación (25) y 30 dientes con un número mayor (30). Utilizamos un sistema de instumentación mecánica ProTaper, acabando la instrumentación en una F2 (25-8%). Dejamos los dientes en tinta china durante 1 semana, para posteriormente haciendo cortes a 1,2,3 y 5 mm del ápice evaluar, al microscopio esteroscópico ( Estéreo Beta de Visión Engineering, Send, Surrey, UK); la presencia de sobreobturación, profundidad de esta filtración y evaluar si la presencia de vástago en sobre extensiones aumenta el índice de filtración de los casos. Resultados: No se observan diferenicas estadísticamente significativas en la extrusión (p=0,387). En cuanto a la filtración apical notamos un mejor sellado con el Thermafil de calibre mayor en todas las mediciones, aunque éstas no son estadísticamente significativas (p= 0,673). Conclusiones: Por los resultados de este estudio parece ser que al utilizar un Thermafil de un diámetro mayor al de la lima apical maestra hay menor índice de filtración y menor cantidad de sobreobturaciones (AU)


Objective: The purpose of this study was to evaluate the overfilling of material and the apical sealing ability of root canals filled using two obturating diameters of thermafil in canal preparated with the same taper and diameter. Material and methods: Sixty one root canal teeth were obturated with Thermafil, 30 with thermafil diameter 25, and 20 with thermafil diameter 25 and 30 with thermafil diameter 30 both with top seal sealer. One canal instrumentation method was used “Protaper” toe end the preparation with a 25-8% file (F2). Folowing obturation, the teeth were prepared for evaluation of the seal using India ink for a week, to continue cutting the root in 4 pieces, 1mm, 2mm, 3mm and 5 mm from the apex to evaluate with the stereoscopic microscope (Estéreo Beta of Vision Engineering: The presence of apical overfilling, the depth of lekeage and evaluate if the presence of core in overfilings increase the lekage in our cases. Results. For overfilling capacity, although we got better results with the thermafil of bigger diameter. However, a not significant difference was present at the p>0,05 between the two diameters of thermafil (p=0,673). Conclusions: By the results of this study it seems that the Thermafil of a bigger diameter creates a better seal and less overfilling (AU)


Asunto(s)
Humanos , Masculino , Femenino , Extrusión Ortodóncica/métodos , Extrusión Ortodóncica/tendencias , Diente/química , Diente , Ápice del Diente , Ápice del Diente , Extrusión Ortodóncica/instrumentación , Extrusión Ortodóncica/estadística & datos numéricos , Diente/ultraestructura , Diente , Obturación Retrógrada , Obturación del Conducto Radicular
11.
Vet Parasitol ; 137(3-4): 379-85, 2006 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-16490319

RESUMEN

A survey was carried out to investigate the presence of cranial helminths in 337 American minks (Mustela vison) from Spain. This information was obtained partly in order to evaluate potential conservation problems and sanitary risks to the congeneric European mink (Mustela lutreola), one of the most endangered carnivores in the world. Skulls and rectal faeces of each specimen were simultaneously analysed. Troglotrema acutum and Skrjabingylus nasicola were found in 5.6% of the M. vison analysed. No cranial lesions were seen in any of the examined skulls. The finding of both helminths in Spanish free-living M. vison specimens enlarges their natural definitive host spectrum in Western Europe. One relatively important focus of T. acutum in M. vison was detected (30.4%) in the Spanish Alava province while S. nasicola was found to be very infrequent. The suitability of both analytical methods was assessed in order to know to what degree coprological analysis reflects the real prevalence of cranial helminths in this host. It is possible to conclude that coprological analysis can be used instead of necropsies to analyse the possible incidence of pathogenic cranial helminths in mustelids. This aspect is very important and useful when trying to analyse the helminthological status of endangered species such as the native mink (M. lutreola) particularly in areas where both congeneric species are present and strict competition occurs.


Asunto(s)
Heces/parasitología , Helmintos/aislamiento & purificación , Visón/parasitología , Cráneo/parasitología , Animales , Animales Salvajes , Conservación de los Recursos Naturales , Reservorios de Enfermedades/veterinaria , Recuento de Huevos de Parásitos/veterinaria , España
12.
Curr Top Microbiol Immunol ; 265: 23-48, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12014193

RESUMEN

Cytokines and chemokines are potent biologic response molecules that play a key role in cellular communication in physiologic and pathophysiologic states. An understanding of the actions and roles of these molecules in CNS biology has been greatly facilitated by molecular genetic approaches that permit the targeted manipulation of gene expression in an intact organism. Studies in promoter-driven transgenic mice with CNS production of a number of cytokines or chemokines have demonstrated that these factors can directly induce a spectrum of cellular alterations often resulting in pronounced neurological disease (Table 1). Thus, these factors, in addition to initiating and maintaining immunoinflammatory responses, can be direct mediators of CNS injury. The neuropathological outcomes in the transgenic mice often recapitulate those reported in human neurological disorders such as MS, neurological diseases associated with AIDS and Alzheimer's disease, pointing to the importance of these animal models to our understanding of the role of cytokines and chemokines in these human disorders. Despite problems of timing and tissue specificity as well as some inconsistencies in the findings from different groups, knockout mice have begun to provide insights that are altering our view of the contribution made by individual cytokines to immunoinflammatory responses in the brain. For example, IL-6 and TNF were originally viewed as having minor and major proinflammatory contributions, respectively, in EAE, but now, based on findings from knockout mice, the opposite seems true. Studies in transgenic and knockout mice now offer strong evidence that, in addition to being mediators of damage, cytokines can have beneficial functions, e.g. the antiviral functions of the IFNs or the trophic and/or neuroprotective actions of some cytokines such as IL-6 and TNF. Clearly, studies in mutant mice, as summarized here, will continue to provide important insights into the nature of cytokine and chemokine actions in the CNS and will offer the possibility that we may identify new targets for effective therapeutic intervention in neuroinflammatory disorders.


Asunto(s)
Sistema Nervioso Central/inmunología , Quimiocinas/inmunología , Citocinas/inmunología , Animales , Animales Modificados Genéticamente , Sistema Nervioso Central/patología , Quimiocinas/deficiencia , Quimiocinas/genética , Citocinas/deficiencia , Citocinas/genética , Interleucinas/inmunología , Ratones , Ratones Noqueados
13.
Neuropharmacology ; 43(8): 1249-57, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12527474

RESUMEN

The homologous regulation of receptors is mediated by G protein-coupled receptor kinases (GRKs) which phosphorylate the agonist-activated receptor. This study was designed to assess the in vivo indirect activation of adrenoceptors or 5-HT receptors by the reuptake blocker desipramine or fluoxetine on the cellular distribution of GRK 2/3 in rat brain. Immunoblot analysis (frontal cortex) with a GRK 2 antibody revealed a unique 80 kDa protein (mixed GRK 2/3) in total homogenate (H) and in membrane (P2) and cytosolic (S2) fractions. The proportion of GRK 2/3 in each fraction, relative to that of H, was: P2/H=0.11 and S2/H=0.45. Acute desipramine (noradrenaline reuptake blocker) increased in a dose- (1-30 mg/kg, i.p.) and time- (1-6 h) dependent manner the content of GRK 2/3 in the membrane (P2/H ratios increased by 37-164%). This effect vanished with a prolonged desipramine (30 mg/kg) exposure (24 h). Desipramine did not alter the content of GRK 2/3 in the cytosol (S2/H ratios). Chronic desipramine (10 mg/kg every 24 h) for 14 days did not change significantly the immunodensity of GRK 2/3 in the membrane or the cytosol. The acute administration (2 h) of fluoxetine (5-HT reuptake blocker; 3-30 mg/kg) did not induce significant changes in the content of GRK 2/3 in the membrane (P2/H ratio) or cytosol (S2/H ratio). The results indicate that the in vivo activation of adrenoceptors by desipramine is associated with a time-dependent modulation of membrane-associated GRK 2/3 (i.e. an acute increase in the kinase content which is followed by a return to the basal expression upon repeated treatment). In contrast, the acute in vivo activation of 5-HT receptors induced by fluoxetine does not result in modulation of GRK 2/3.


Asunto(s)
Antidepresivos Tricíclicos/administración & dosificación , Encéfalo/efectos de los fármacos , Proteínas Quinasas Dependientes de AMP Cíclico/biosíntesis , Desipramina/administración & dosificación , Fluoxetina/administración & dosificación , Proteínas Serina-Treonina Quinasas/biosíntesis , Animales , Encéfalo/enzimología , Membrana Celular/efectos de los fármacos , Membrana Celular/enzimología , Quinasa 3 del Receptor Acoplado a Proteína-G , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica/fisiología , Masculino , Ratas , Ratas Sprague-Dawley , Quinasas de Receptores Adrenérgicos beta
14.
J Exp Med ; 194(12): 1755-66, 2001 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-11748277

RESUMEN

Using transgenic mice that replicate hepatitis B virus (HBV) at high levels in the liver as recipients of HBV-specific cytotoxic T lymphocytes (CTLs), we showed that the chemokines responsive to gamma-2/IFN-gamma inducible protein ([Crg2]IP-10) and monokine induced by interferon-gamma (Mig) are rapidly and strongly induced in the liver after CTL transfer. The transferred CTLs produce neither chemokine; rather, they activate (via the secretion of IFN-gamma) hepatocytes and nonparenchymal cells of the liver to produce (Crg2)IP-10 and Mig. Importantly, blocking these chemokines in vivo reduces the recruitment of host-derived lymphomononuclear cells into the liver and the severity of the liver disease without affecting the IFN-gamma-dependent antiviral potential of the CTLs. The finding that neutralization of these chemokines is associated with maintenance of antiviral effects but diminished tissue damage may be significant for the development of immunotherapeutic approaches for the treatment of chronic HBV infection.


Asunto(s)
Citotoxicidad Inmunológica , Virus de la Hepatitis B/inmunología , Hepatitis B/inmunología , Interferón gamma/inmunología , Monocinas/inmunología , Linfocitos T Citotóxicos/inmunología , Animales , Quimiocina CXCL10 , Hepatitis B/genética , Hepatitis B/patología , Interferón gamma/genética , Hígado/inmunología , Hígado/patología , Hígado/virología , Ratones , Ratones Transgénicos , Monocinas/genética
15.
J Immunol ; 167(9): 5485-93, 2001 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-11673569

RESUMEN

IL-12, a cytokine produced by microglia, may regulate cellular immunity at a localized level in the CNS. To investigate this further, we examined the consequences of peripheral immune stimulation without specific autoantigen in wild-type or transgenic (termed GF-IL12) mice with astrocyte production of the bioactive IL-12 p75 heterodimer. Active immunization with CFA and pertussis toxin, a procedure known to stimulate a robust type 1-biased immune response, produced CNS immune pathology from which GF-IL12 but not wild-type mice developed signs of clinical disease consisting of loss of activity, piloerection, mild tremor, and motor change. All immunized mice had some degree of mononuclear cell infiltration into the brain; however, the severity of this was markedly increased in GF-IL12 mice where leukocytes accumulated in perivascular and parenchymal locations. Accumulating cells consisted of CD4(+) and CD8(+) T cells and macrophage/microglia. Moreover, expression of cytokines (IFN-gamma and TNF), chemokines (IFN-inducible protein-10 and RANTES), the immune accessory molecules, MHC class II, B7.2, ICAM-1 and VCAM-1, and NO synthase-2 was induced in the CNS of the GF-IL12 mice. Therefore, peripheral immunization of GF-IL12 but not wild-type mice can provoke active type 1 immunity in the brain-a process that does not require CNS-specific immunizing autoantigen. These findings indicate that the cytokine milieu of a tissue can dramatically influence the development of intrinsic immune responses and associated pathology.


Asunto(s)
Astrocitos/metabolismo , Autoantígenos/inmunología , Encéfalo/inmunología , Interleucina-12/fisiología , Animales , Encéfalo/patología , Quimiocinas/biosíntesis , Citocinas/biosíntesis , Adyuvante de Freund/inmunología , Inmunización , Molécula 1 de Adhesión Intercelular/biosíntesis , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Óxido Nítrico Sintasa/biosíntesis , Óxido Nítrico Sintasa de Tipo II , Toxina del Pertussis , Factores de Virulencia de Bordetella/inmunología
16.
J Virol ; 75(15): 7067-77, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11435587

RESUMEN

The CXC chemokine gamma interferon (IFN-gamma)-inducible protein CXCL10/IP-10 is markedly elevated in cerebrospinal fluid and brain of individuals infected with human immunodeficiency virus type 1 (HIV-1) and is implicated in the pathogenesis of HIV-associated dementia (HAD). To explore the possible role of CXCL10/IP-10 in HAD, we examined the expression of this and other chemokines in the central nervous system (CNS) of transgenic mice with astrocyte-targeted expression of HIV gp120 under the control of the glial fibrillary acidic protein (GFAP) promoter, a murine model for HIV-1 encephalopathy. Compared with wild-type controls, CNS expression of the CC chemokine gene CCL2/MCP-1 and the CXC chemokine genes CXCL10/IP-10 and CXCL9/Mig was induced in the GFAP-HIV gp120 mice. CXCL10/IP-10 RNA expression was increased most and overlapped the expression of the transgene-encoded HIV gp120 gene. Astrocytes and to a lesser extent microglia were identified as the major cellular sites for CXCL10/IP-10 gene expression. There was no detectable expression of any class of IFN or their responsive genes. In astrocyte cultures, soluble recombinant HIV gp120 protein was capable of directly inducing CXCL10/IP-10 gene expression a process that was independent of STAT1. These findings highlight a novel IFN- and STAT1-independent mechanism for the regulation of CXCL10/IP-10 expression and directly link expression of HIV gp120 to the induction of CXCL10/IP-10 that is found in HIV infection of the CNS. Finally, one function of IP-10 expression may be the recruitment of leukocytes to the CNS, since the brain of GFAP-HIV gp120 mice had increased numbers of CD3(+) T cells that were found in close proximity to sites of CXCL10/IP-10 RNA expression.


Asunto(s)
Astrocitos/metabolismo , Quimiocinas CXC/genética , Proteína gp120 de Envoltorio del VIH/metabolismo , VIH-1/metabolismo , Animales , Astrocitos/citología , Encéfalo/metabolismo , Encéfalo/patología , Células Cultivadas , Quimiocina CXCL10 , Quimiocinas CXC/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/fisiología , Expresión Génica , Proteína Ácida Fibrilar de la Glía/genética , Proteína gp120 de Envoltorio del VIH/genética , VIH-1/genética , Humanos , Interferón-alfa/metabolismo , Interferón-alfa/farmacología , Interferón gamma/metabolismo , Interferón gamma/farmacología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Receptores CXCR3 , Receptores de Quimiocina/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Factor de Transcripción STAT1 , Solubilidad , Linfocitos T/citología , Transactivadores/genética , Transactivadores/fisiología
18.
Int Immunol ; 13(8): 1085-93, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11470778

RESUMEN

To further define the molecular basis of tolerance to a peripherally expressed antigen we have correlated differences in functional capacity with biochemical events in hemagglutinin (HA)-specific cytotoxic T lymphocyte (CTL) clones derived either from a conventional B10.D2 mouse that is not tolerant to HA (D2 Clone 6) or from an InsHA mouse that is tolerant to HA (InsHA Clone 12). D2 Clone 6, but not InsHA Clone 12, triggers diabetes following in vivo transfer into irradiated InsHA hosts. This diabetogenic clone shows complete and sustained phosphorylation of TCR zeta chain and ZAP-70 following stimulation with HA-pulsed antigen-presenting cells. In contrast, InsHA Clone 12 showed only partial phosphorylation of TCR zeta and no phosphorylation of ZAP-70. There was no defect in activation or recruitment of Lck to the TCR complex in both the clones following stimulation with the cognate antigen. This deficiency in the proximal signaling in the InsHA Clone 12 could be overcome by increasing the strength of signal through the CD3-TCR complex, indicating that the signaling machinery of InsHA Clone 12 was functional. These data demonstrate that the HA-responsive CD8(+) T cells that can be retrieved from InsHA mice after tolerance induction respond to HA as a partial agonist/antagonist.


Asunto(s)
Citotoxicidad Inmunológica , Tolerancia Inmunológica , Linfocitos T Citotóxicos/inmunología , Linfocitos T Citotóxicos/metabolismo , Animales , Células Clonales , Diabetes Mellitus Experimental/inmunología , Inmunofenotipificación , Ligandos , Proteína Tirosina Quinasa p56(lck) Específica de Linfocito/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Fosforilación , Proteínas Tirosina Quinasas/metabolismo , Transducción de Señal/inmunología , Linfocitos T Citotóxicos/enzimología , Proteína Tirosina Quinasa ZAP-70
20.
O.R.L.-DIPS ; 28(2): 100-102, mar. 2001. ilus
Artículo en Es | IBECS | ID: ibc-7870

RESUMEN

Presentamos un caso de un hombre de 54 años con una parálisis recurrencial derecha. La resonancia magnética (RMN) mostró una masa en el ángulo pontocerebeloso derecho. Los síntomas clínicos más frecuentes son alteraciones cocleares (hipoacusia, acúfenos...), vestibulares (vértigo, inestabilidad en la marcha...) y de los nervios trigémino y facial. Una parálisis recurrencial como primera manifestación de un neurinoma del acústico es una patología inusual (AU)


Asunto(s)
Masculino , Persona de Mediana Edad , Humanos , Recurrencia , Parálisis Facial/complicaciones , Parálisis Facial/diagnóstico , Parálisis Facial/cirugía , Parálisis Facial/etiología , Parálisis/complicaciones , Parálisis/diagnóstico , Enfermedades Cocleares/complicaciones , Enfermedades Cocleares/diagnóstico , Trastornos de la Voz/complicaciones , Trastornos de la Voz/diagnóstico , Trastornos de la Voz/etiología , Josamicina/efectos adversos , Josamicina/uso terapéutico , Cefuroxima/efectos adversos , Cefuroxima/uso terapéutico , Laringoscopía/métodos , Laringoscopía , Audiometría/métodos , Audiometría , Neurilemoma/complicaciones , Neurilemoma/diagnóstico , Neurilemoma/patología , Neurilemoma , Sordera/complicaciones , Sordera/diagnóstico , Sordera/etiología , Nervio Coclear/patología , Neuroma Acústico/cirugía , Neuroma Acústico/complicaciones , Neuroma Acústico/diagnóstico , Neuroma Acústico/etiología , Neuroma Acústico/patología , Neuroma Acústico , Espectroscopía de Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética , Neoplasias del Oído/complicaciones , Neoplasias del Oído/diagnóstico , Neoplasias del Oído/cirugía , Pérdida Auditiva Súbita/complicaciones , Pérdida Auditiva Súbita/diagnóstico , Pérdida Auditiva Súbita/etiología , Tórax/patología , Tórax , Laringe/patología , Laringe , Laringe , Esófago/patología , Esófago , Esófago , Toxoplasma/aislamiento & purificación , Toxoplasma/microbiología , Nervios Craneales/patología
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