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1.
Am J Med Genet A ; 194(7): e63603, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38511620

RESUMEN

There is an emerging body of evidence showing that young patients, post haematopoietic stem cell transplantation (HSCT), can develop skeletal changes that mimic an osteochondrodysplasia process. The key discriminator is that these children have had otherwise normal growth and skeletal development before the therapeutic intervention (HSCT), typically for a haematological malignancy. Herein we present that case of a boy who underwent HSCT for Haemophagocytic Lymphohistiocytosis (HLH) aged 2 years. Following Intervention with HSCT this boy's growth has severely decelerated (stature less than 1st centile matched for age) and he has developed a spondyloepiphyseal dysplasia.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Linfohistiocitosis Hemofagocítica , Osteocondrodisplasias , Humanos , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Masculino , Osteocondrodisplasias/genética , Osteocondrodisplasias/patología , Preescolar , Linfohistiocitosis Hemofagocítica/genética , Linfohistiocitosis Hemofagocítica/patología , Linfohistiocitosis Hemofagocítica/etiología , Trastornos del Crecimiento/patología , Trastornos del Crecimiento/etiología , Trastornos del Crecimiento/genética
2.
Ir Med J ; 113(4): 61, 2020 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-32268054

RESUMEN

Presentation To describe a case of cystic echinococcosis (CE) in a previously healthy child and review epidemiology of CE in Ireland. Diagnosis A previously healthy 6 year old girl was found to have a cystic lesion in the right lobe of her liver. Serology for Echinococcus granulosus was positive, and radiological features were suggestive of CE. Treatment The patient was pre-treated with anti-helminthic medications before undergoing a liver segmentectomy to remove the cyst, and received further treatment with albendazole after surgery. Histological findings were consistent with CE due to E. granulosus, likely acquired during travel to continental Europe. Conclusion CE should be considered in the differential of children with asymptomatic cysts in the liver and/or lung, and a travel history elucidated in such cases.


Asunto(s)
Equinococosis Hepática/diagnóstico , Equinococosis Hepática/terapia , Viaje , Albendazol/administración & dosificación , Animales , Antihelmínticos/administración & dosificación , Anticuerpos Antihelmínticos/sangre , Infecciones Asintomáticas , Biomarcadores/sangre , Niño , Diagnóstico Diferencial , Imagen de Difusión por Resonancia Magnética , Equinococosis Hepática/diagnóstico por imagen , Equinococosis Hepática/parasitología , Echinococcus granulosus/inmunología , Femenino , Hepatectomía/métodos , Humanos , Irlanda , Resultado del Tratamiento
3.
Psychol Med ; 48(3): 451-462, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28712364

RESUMEN

BACKGROUND: Schizotypal traits are considered a phenotypic-indicator of schizotypy, a latent personality organization reflecting a putative liability for psychosis. To date, no previous study has examined the comparability of factorial structures across samples originating from different countries and cultures. The main goal was to evaluate the factorial structure and reliability of the Schizotypal Personality Questionnaire (SPQ) scores by amalgamating data from studies conducted in 12 countries and across 21 sites. METHOD: The overall sample consisted of 27 001 participants (37.5% males, n = 4251 drawn from the general population). The mean age was 22.12 years (s.d. = 6.28, range 16-55 years). The SPQ was used. Confirmatory factor analysis (CFA) and Multilevel CFA (ML-CFA) were used to evaluate the factor structure underlying the SPQ scores. RESULTS: At the SPQ item level, the nine factor and second-order factor models showed adequate goodness-of-fit. At the SPQ subscale level, three- and four-factor models displayed better goodness-of-fit indices than other CFA models. ML-CFA showed that the intraclass correlation coefficients values were lower than 0.106. The three-factor model showed adequate goodness of fit indices in multilevel analysis. The ordinal α coefficients were high, ranging from 0.73 to 0.94 across individual samples, and from 0.84 to 0.91 for the combined sample. CONCLUSIONS: The results are consistent with the conceptual notion that schizotypal personality is a multifaceted construct and support the validity and utility of SPQ in cross-cultural research. We discuss theoretical and clinical implications of our results for diagnostic systems, psychosis models and cross-national mental health strategies.


Asunto(s)
Inventario de Personalidad , Psicometría/estadística & datos numéricos , Trastorno de la Personalidad Esquizotípica/diagnóstico , Trastorno de la Personalidad Esquizotípica/psicología , Adolescente , Adulto , Análisis Factorial , Femenino , Humanos , Internacionalidad , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Encuestas y Cuestionarios , Adulto Joven
4.
Biochim Biophys Acta ; 1852(5): 749-58, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25619687

RESUMEN

Long chain fatty acids bind to carnitine and form long chain acyl carnitine (LCAC), to enter into the mitochondria. They are oxidized in the mitochondrial matrix. LCAC accumulates rapidly under metabolic disorders, such as acute cardiac ischemia, chronic heart failure or diabetic cardiomyopathy. LCAC accumulation is associated with severe cardiac arrhythmia including ventricular tachycardia or fibrillation. We thus hypothesized that palmitoyl-carnitine (PC), alters mitochondrial function leading to Ca(2+) dependent-arrhythmia. In isolated cardiac mitochondria from C57Bl/6 mice, application of 10µM PC decreased adenine nucleotide translocase (ANT) activity without affecting mitochondrial permeability transition pore (mPTP) opening. Mitochondrial reactive oxygen species (ROS) production, measured with MitoSOX Red dye in isolated ventricular cardiomyocytes, increased significantly under PC application. Inhibition of ANT by bongkrekic acid (20 µM) prevented PC-induced mitochondrial ROS production. In addition, PC increased type 2 ryanodine receptor (RyR2) oxidation, S-nitrosylation and dissociation of FKBP12.6 from RyR2, and therefore increased sarcoplasmic reticulum (SR) Ca(2+) leak. ANT inhibition or anti-oxidant strategy (N-acetylcysteine) prevented SR Ca(2+) leak, FKBP12.6 depletion and RyR2 oxidation/S-nitrosylation induced by PC. Finally, both bongkrekic acid and NAC significantly reduced spontaneous Ca(2+) wave occurrences under PC. Altogether, these results suggest that an elevation of PC disturbs ANT activity and alters Ca(2+) handling in a ROS-dependent pathway, demonstrating a new pathway whereby altered FA metabolism may contribute to the development of ventricular arrhythmia in pathophysiological conditions.


Asunto(s)
Calcio/metabolismo , Translocasas Mitocondriales de ADP y ATP/antagonistas & inhibidores , Miocitos Cardíacos/efectos de los fármacos , Palmitoilcarnitina/farmacología , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Retículo Sarcoplasmático/efectos de los fármacos , Acetilcisteína/farmacología , Animales , Ácido Bongcréquico/farmacología , Células Cultivadas , Depuradores de Radicales Libres/farmacología , Immunoblotting , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones Endogámicos C57BL , Microscopía Confocal , Mitocondrias Cardíacas/efectos de los fármacos , Mitocondrias Cardíacas/metabolismo , Mitocondrias Cardíacas/fisiología , Translocasas Mitocondriales de ADP y ATP/metabolismo , Proteínas de Transporte de Membrana Mitocondrial/metabolismo , Poro de Transición de la Permeabilidad Mitocondrial , Miocitos Cardíacos/citología , Miocitos Cardíacos/metabolismo , Óxido Nítrico/metabolismo , Oxidación-Reducción/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Retículo Sarcoplasmático/metabolismo , Proteínas de Unión a Tacrolimus/metabolismo
5.
J Xray Sci Technol ; 23(6): 791-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26756414

RESUMEN

X-ray backscatter imaging can be used for a wide range of imaging applications, in particular for industrial inspection and portal security. Currently, the application of this imaging technique to the detection of landmines is limited due to the surrounding sand or soil strongly attenuating the 10s to 100s of keV X-rays required for backscatter imaging. Here, we introduce a new approach involving a 140 MeV short-pulse (< 100 fs) electron beam generated by laser wakefield acceleration to probe the sample, which produces Bremsstrahlung X-rays within the sample enabling greater depths to be imaged. A variety of detector and scintillator configurations are examined, with the best time response seen from an absorptive coated BaF2 scintillator with a bandpass filter to remove the slow scintillation emission components. An X-ray backscatter image of an array of different density and atomic number items is demonstrated. The use of a compact laser wakefield accelerator to generate the electron source, combined with the rapid development of more compact, efficient and higher repetition rate high power laser systems will make this system feasible for applications in the field. Content includes material subject to Dstl (c) Crown copyright (2014). Licensed under the terms of the Open Government Licence except where otherwise stated. To view this licence, visit http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3 or write to the Information Policy Team, The National Archives, Kew, London TW9 4DU, or email: psi@ nationalarchives.gsi.gov.uk.


Asunto(s)
Bombas (Dispositivos Explosivos)/clasificación , Rayos Láser , Intensificación de Imagen Radiográfica/instrumentación , Dispersión de Radiación , Tomografía Computarizada por Rayos X/instrumentación , Guerra , Diseño de Equipo , Análisis de Falla de Equipo , Fantasmas de Imagen , Rayos X
6.
Scand J Immunol ; 76(4): 359-70, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22690903

RESUMEN

Toll-like receptors (TLRs) are central to innate immunity and yet their expression is widespread and not restricted to professional inflammatory cells. TLRs have been reported on adipocytes and have been implicated in obesity-associated pathologies such as diabetes. Why TLRs are found on adipocytes is not clear although one hypothesis is that they may coordinate energy utilization for the energy intensive process of an immune response. We have explored TLR signalling in primary human in vitro differentiated adipocytes and investigated the specific adapter molecules that are involved. Only lipopolysaccharide (LPS), poly(I:C), Pam3CSK4 and MALP-2 could induce the production of IL-6, IL-8 and MCP-1 by adipocytes. Poly(I:C) alone caused a strong induction of type I interferons, as assessed by IP-10 production. Using siRNA, it was confirmed that LPS-dependent signalling in adipocytes occurs via TLR4 utilizing the adapter molecules MyD88, Mal and TRIF and caused rapid degradation of IκBα. Pam3CSK4 signalling utilized TLR2, MyD88 and Mal (but not TRIF). However, the response to poly(I:C) observed in these cells appeared not to require TRIF, but MyD88 was required for induction of NFκB-dependent cytokines by Poly(I:C). Despite this, IκBα degradation could not be detected in poly(I:C) stimulated adipocytes at any time-point up to 4 h. Indeed, IL-6 transcription was not induced until 8-16 h after exposure. These data suggest that Pam3CSK4 and LPS signal via the expected routes in human adipocytes, whereas poly(I:C)/TLR3 signalling may act via a TRIF-independent, MyD88-dependent route.


Asunto(s)
Adipocitos/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Transducción de Señal/genética , Receptores Toll-Like/metabolismo , Proteínas Adaptadoras del Transporte Vesicular/genética , Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Adipocitos/citología , Adipocitos/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Quimiocina CCL2/biosíntesis , Humanos , Proteínas I-kappa B/genética , Proteínas I-kappa B/metabolismo , Interleucina-6/biosíntesis , Interleucina-8/biosíntesis , Lipopéptidos/farmacología , Lipopolisacáridos/farmacología , Factor 88 de Diferenciación Mieloide/farmacología , Inhibidor NF-kappaB alfa , Poli I-C/farmacología , Cultivo Primario de Células , Isoformas de Proteínas/antagonistas & inhibidores , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , ARN Interferente Pequeño/genética , Transducción de Señal/efectos de los fármacos , Receptores Toll-Like/antagonistas & inhibidores , Receptores Toll-Like/genética
7.
Phys Rev Lett ; 108(13): 135004, 2012 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-22540709

RESUMEN

We demonstrate a new high-order harmonic generation mechanism reaching the "water window" spectral region in experiments with multiterawatt femtosecond lasers irradiating gas jets. A few hundred harmonic orders are resolved, giving µJ/sr pulses. Harmonics are collectively emitted by an oscillating electron spike formed at the joint of the boundaries of a cavity and bow wave created by a relativistically self-focusing laser in underdense plasma. The spike sharpness and stability are explained by catastrophe theory. The mechanism is corroborated by particle-in-cell simulations.

8.
Phys Rev Lett ; 109(1): 015001, 2012 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-23031109

RESUMEN

This Letter describes the first experimental demonstration of the guiding of a relativistic electron beam in a solid target using two colinear, relativistically intense, picosecond laser pulses. The first pulse creates a magnetic field that guides the higher-current, fast-electron beam generated by the second pulse. The effects of intensity ratio, delay, total energy, and intrinsic prepulse are examined. Thermal and Kα imaging show reduced emission size, increased peak emission, and increased total emission at delays of 4-6 ps, an intensity ratio of 10∶1 (second:first) and a total energy of 186 J. In comparison to a single, high-contrast shot, the inferred fast-electron divergence is reduced by 2.7 times, while the fast-electron current density is increased by a factor of 1.8. The enhancements are reproduced with modeling and are shown to be due to the self-generation of magnetic fields. Such a scheme could be of considerable benefit to fast-ignition inertial fusion.

9.
Phys Rev Lett ; 106(18): 185004, 2011 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-21635098

RESUMEN

The effect of lattice structure on the transport of energetic (MeV) electrons in solids irradiated by ultraintense laser pulses is investigated using various allotropes of carbon. We observe smooth electron transport in diamond, whereas beam filamentation is observed with less ordered forms of carbon. The highly ordered lattice structure of diamond is shown to result in a transient state of warm dense carbon with metalliclike conductivity, at temperatures of the order of 1-100 eV, leading to suppression of electron beam filamentation.

10.
Methods Cell Biol ; 164: 95-112, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34225921

RESUMEN

In the perspective to evaluate the toxicity of drug candidates or the exploration of intracellular signaling pathways of cell stress response and pathophysiological conditions, we propose to evaluate cell death, autophagy, mitochondrial network and energetic metabolism by a series of optimized joint protocols for neonatal primary rat cardiomyocytes or H9c2 cardiac cell line in 96 well microtiter plates. We used Digitoxigenin and Digoxin, two cardiac glycosides, and Rapamycin as control drugs, for inhibition of oxidative stress-induced cell death and autophagy induction, respectively.


Asunto(s)
Autofagia , Mitocondrias , Animales , Apoptosis , Muerte Celular , Mitocondrias/metabolismo , Miocitos Cardíacos , Estrés Oxidativo , Ratas
11.
J Exp Med ; 175(1): 121-9, 1992 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-1730912

RESUMEN

The relationship between the characterized mouse regulators of complement activation (RCA) genes and the 190-kD mouse complement receptor 1 (MCR1), 155-kD mouse complement receptor 2 (MCR2), and mouse p65 is unclear. One mouse RCA gene, designated MCR2 (or Cr2), encodes alternatively spliced 21 and 15 short consensus repeat (SCR)-containing transcripts that crosshybridize with cDNAs of both human CR2 and CR1, or CR2 alone, respectively. A five SCR-containing transcript derived from a second unique gene, designated Crry, also crosshybridizes with human CR1. We have previously shown that the 155-kD MCR2 is encoded by the 15 SCR-containing transcript. To analyze the protein products of the other transcripts, which are considered the genetic homologues of human CR1, we have expressed the 21 and the 5 SCR-containing cDNAs in the human K562 erythroleukemia cell line. We demonstrate that cells expressing the 21 SCR transcript express the 190-kD MCR1 protein. These cells react with five unique rat anti-MCR1 monoclonal antibodies, including the 8C12 antibody considered to be monospecific for MCR1. In addition, these cells efficiently form rosettes with mouse C3b-bearing sheep erythrocytes. In contrast, cells expressing the five SCR-containing Crry transcript are strongly recognized by an anti-human CR1 antibody that also defines the mouse p65 protein. Using a functional assay that measures the surface deposition of C3 activated via the classical complement pathway, we show that Crry/p65-expressing cells have a markedly decreased amount of C3 deposited on them as compared with control cells expressing the antisense construct or cells expressing MCR1 or MCR2. This suggests that Crry has intrinsic complement regulatory activity.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Receptores de Complemento/fisiología , Animales , Anticuerpos , Línea Celular , Clonación Molecular , ADN/genética , ADN/aislamiento & purificación , Electroforesis en Gel de Poliacrilamida , Citometría de Flujo , Humanos , Ratones , Modelos Estructurales , Peso Molecular , Conformación Proteica , Receptores de Complemento/genética , Receptores de Complemento/aislamiento & purificación , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Formación de Roseta
12.
J Exp Med ; 172(2): 457-62, 1990 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-2142719

RESUMEN

Fresh CD3-, CD16+ lymphocytes that adhered to selected allogeneic lymphoblastoid cell lines (LCL) were cultured with LCL in the presence of IL-2-containing medium. The resulting lines as well as clones derived from these lines expressed CD16 and/or CD56, but lacked detectable CD3 or TCR-alpha/beta or TCR-gamma/delta complexes on the cell surface. Northern blot analysis failed to detect CD3 epsilon or TCR-beta transcripts, but revealed the presence of a TCR-gamma chain transcript in one of these lines. In addition to displaying potent cytolytic activity against K562 erythroleukemia cells (a classical NK target), the vast majority of these lines and clones lysed their specific stimulator LCL to a significantly greater extent than irrelevant LCL. This selective killing was inhibited by the addition of cold stimulator LCL or K562 cells, or anti-LFA 1 mAbs, but not by irrelevant LCL or mAbs to CD3, class I or class II MHC antigens. These results indicate that some CD3- lymphocytes, phenotypically indistinguishable from NK cells, can recognize and lyse allogeneic targets in a specific manner.


Asunto(s)
Antígenos CD/análisis , Células Asesinas Naturales/inmunología , Anticuerpos Monoclonales/inmunología , Complejo Antígeno-Anticuerpo/análisis , Antígenos de Diferenciación/análisis , Antígenos de Diferenciación de Linfocitos T/análisis , Complejo CD3 , Línea Celular , Células Cultivadas , Células Clonales , Citotoxicidad Inmunológica , Citometría de Flujo , Humanos , Sustancias Macromoleculares , Receptores de Antígenos de Linfocitos T/análisis , Receptores de Antígenos de Linfocitos T/genética , Receptores Fc/análisis , Receptores de IgG
13.
J Exp Med ; 189(2): 381-94, 1999 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-9892620

RESUMEN

The barrier function of mitochondrial membranes is perturbed early during the apoptotic process. Here we show that the mitochondria contain a caspase-like enzymatic activity cleaving the caspase substrate Z-VAD.afc, in addition to three biological activities previously suggested to participate in the apoptotic process: (a) cytochrome c; (b) an apoptosis-inducing factor (AIF) which causes isolated nuclei to undergo apoptosis in vitro; and (c) a DNAse activity. All of these factors, which are biochemically distinct, are released upon opening of the permeability transition (PT) pore in a coordinate, Bcl-2-inhibitable fashion. Caspase inhibitors fully neutralize the Z-VAD.afc-cleaving activity, have a limited effect on the AIF activity, and have no effect at all on the DNase activities. Purification of proteins reacting with the biotinylated caspase substrate Z-VAD, immunodetection, and immunodepletion experiments reveal the presence of procaspase-2 and -9 in mitochondria. Upon induction of PT pore opening, these procaspases are released from purified mitochondria and become activated. Similarly, upon induction of apoptosis, both procaspases redistribute from the mitochondrion to the cytosol and are processed to generate enzymatically active caspases. This redistribution is inhibited by Bcl-2. Recombinant caspase-2 and -9 suffice to provoke full-blown apoptosis upon microinjection into cells. Altogether, these data suggest that caspase-2 and -9 zymogens are essentially localized in mitochondria and that the disruption of the outer mitochondrial membrane occurring early during apoptosis may be critical for their subcellular redistribution and activation.


Asunto(s)
Apoptosis/fisiología , Caspasas/metabolismo , Flavoproteínas , Mitocondrias/enzimología , Animales , Factor Inductor de la Apoptosis , Caspasa 2 , Caspasa 9 , Línea Celular , Inhibidores de Cisteína Proteinasa/farmacología , Grupo Citocromo c/metabolismo , Activación Enzimática , Precursores Enzimáticos/metabolismo , Femenino , Humanos , Membranas Intracelulares/metabolismo , Proteínas de la Membrana/metabolismo , Ratones , Ratones Endogámicos BALB C , Microinyecciones , Proteínas Nucleares/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteínas Recombinantes/metabolismo
14.
J Exp Med ; 187(8): 1261-71, 1998 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-9547337

RESUMEN

Early in programmed cell death (apoptosis), mitochondrial membrane permeability increases. This is at least in part due to opening of the permeability transition (PT) pore, a multiprotein complex built up at the contact site between the inner and the outer mitochondrial membranes. The PT pore has been previously implicated in clinically relevant massive cell death induced by toxins, anoxia, reactive oxygen species, and calcium overload. Here we show that PT pore complexes reconstituted in liposomes exhibit a functional behavior comparable with that of the natural PT pore present in intact mitochondria. The PT pore complex is regulated by thiol-reactive agents, calcium, cyclophilin D ligands (cyclosporin A and a nonimmunosuppressive cyclosporin A derivative), ligands of the adenine nucleotide translocator, apoptosis-related endoproteases (caspases), and Bcl-2-like proteins. Although calcium, prooxidants, and several recombinant caspases (caspases 1, 2, 3, 4, and 6) enhance the permeability of PT pore-containing liposomes, recombinant Bcl-2 or Bcl-XL augment the resistance of the reconstituted PT pore complex to pore opening. Mutated Bcl-2 proteins that have lost their cytoprotective potential also lose their PT modulatory capacity. In conclusion, the PT pore complex may constitute a crossroad of apoptosis regulation by caspases and members of the Bcl-2 family.


Asunto(s)
Apoptosis , Cisteína Endopeptidasas/metabolismo , Proteínas de la Membrana/metabolismo , Mitocondrias/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Animales , Encéfalo/metabolismo , Liposomas , Proteínas de la Membrana/antagonistas & inhibidores , Ratones , Permeabilidad , Ratas , Proteína bcl-X
15.
J Exp Med ; 193(4): 509-19, 2001 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-11181702

RESUMEN

Viral protein R (Vpr), an apoptogenic accessory protein encoded by HIV-1, induces mitochondrial membrane permeabilization (MMP) via a specific interaction with the permeability transition pore complex, which comprises the voltage-dependent anion channel (VDAC) in the outer membrane (OM) and the adenine nucleotide translocator (ANT) in the inner membrane. Here, we demonstrate that a synthetic Vpr-derived peptide (Vpr52-96) specifically binds to the intermembrane face of the ANT with an affinity in the nanomolar range. Taking advantage of this specific interaction, we determined the role of ANT in the control of MMP. In planar lipid bilayers, Vpr52-96 and purified ANT cooperatively form large conductance channels. This cooperative channel formation relies on a direct protein-protein interaction since it is abolished by the addition of a peptide corresponding to the Vpr binding site of ANT. When added to isolated mitochondria, Vpr52-96 uncouples the respiratory chain and induces a rapid inner MMP to protons and NADH. This inner MMP precedes outer MMP to cytochrome c. Vpr52-96-induced matrix swelling and inner MMP both are prevented by preincubation of purified mitochondria with recombinant Bcl-2 protein. In contrast to König's polyanion (PA10), a specific inhibitor of the VDAC, Bcl-2 fails to prevent Vpr52-96 from crossing the mitochondrial OM. Rather, Bcl-2 reduces the ANT-Vpr interaction, as determined by affinity purification and plasmon resonance studies. Concomitantly, Bcl-2 suppresses channel formation by the ANT-Vpr complex in synthetic membranes. In conclusion, both Vpr and Bcl-2 modulate MMP through a direct interaction with ANT.


Asunto(s)
Productos del Gen vpr/farmacología , Membranas Intracelulares/metabolismo , Mitocondrias/metabolismo , Translocasas Mitocondriales de ADP y ATP/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Secuencia de Aminoácidos , VIH-1 , Canales Iónicos/metabolismo , Liposomas , Modelos Biológicos , Modelos Moleculares , Datos de Secuencia Molecular , Consumo de Oxígeno , Fragmentos de Péptidos/farmacología , Permeabilidad , Unión Proteica , Resonancia por Plasmón de Superficie , Productos del Gen vpr del Virus de la Inmunodeficiencia Humana
16.
Clin Exp Immunol ; 162(3): 487-93, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20846165

RESUMEN

The poor prognosis of obesity is now known to involve a proinflammatory state associated with elevated circulating levels of cytokines and with macrophage infiltration of adipose tissue. In particular, Toll-like receptor (TLR)-4-driven adipose inflammation has been implicated recently in obesity and the development of diabetes. Adipocytes are now recognized as an important source of cytokine and chemokine production, including interleukin (IL)-6 and monocyte chemotractant protein (MCP)-1, and this appears to be a key step in the development of the obesity-associated inflammatory state. Interventions targeted at adipocyte inflammation may therefore form novel therapies to treat or prevent medical complications of obesity. We set out to explore whether anti-inflammatory interventions which are effective in conventional immune cells would operate on primary human cultures of in-vitro differentiated adipocytes. IL-10 was ineffective against TLR-4-induced cytokine secretion due to lack of IL-10 receptor on human adipocytes, in contrast to the widely used murine 3T3-L1 adipocyte model, which is known to respond to IL-10. Adenoviral delivery of an IL-10 receptor construct to the cells restored IL-10 responsiveness as assessed by signal transducer and activator of transcription-3 (STAT-3) phosphorylation. However, the small molecule nuclear factor (NF)-κB inhibitors 2-[(aminocarbonyl)amino]-5-(4-fluorophenyl)-3-thiophenecarboxamide (TPCA)-1 and carbobenzoxyl-Ile-Glu(O-t-butyl)-Ala-leucinal (PSI) as well as adenovirally delivered dominant negative inhibitor of IkappaB kinase 2 (IKK2) and wild-type IκBα were effective inhibitors of TLR-4-driven IL-6 and MCP-1 induction. These data identify a central role for canonical NF-κB signalling in adipocyte cytokine induction and indicate that small molecule inhibitors of NF-κB may form the basis of future treatments for obesity-related conditions where adipocyte inflammatory signalling is implicated.


Asunto(s)
Adipocitos/metabolismo , Inflamación , FN-kappa B/metabolismo , Obesidad/inmunología , Receptores de Interleucina-10/metabolismo , Adipocitos/efectos de los fármacos , Adipocitos/inmunología , Adipocitos/patología , Amidas/farmacología , Células Cultivadas , Quimiocina CCL2/biosíntesis , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Humanos , Interleucina-10/inmunología , Interleucina-10/metabolismo , Interleucina-6/biosíntesis , Interleucina-6/genética , Interleucina-6/metabolismo , FN-kappa B/antagonistas & inhibidores , FN-kappa B/inmunología , Obesidad/tratamiento farmacológico , Receptores de Interleucina-10/genética , Receptores de Interleucina-10/inmunología , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT3/metabolismo , Tiofenos/farmacología , Receptor Toll-Like 4/inmunología , Receptor Toll-Like 4/metabolismo , Transgenes/genética
17.
Phys Rev Lett ; 105(19): 195008, 2010 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-21231179

RESUMEN

The use of two separate ultraintense laser pulses in laser-proton acceleration was compared to the single pulse case employing the same total laser energy. A double pulse profile, with the temporal separation of the pulses varied between 0.75-2.5 ps, was shown to result in an increased maximum proton energy and an increase in conversion efficiency to fast protons by up to a factor of 3.3. Particle-in-cell simulations indicate the existence of a two stage acceleration process. The second phase, induced by the main pulse preferentially accelerates slower protons located deeper in the plasma, in contrast to conventional target normal sheath acceleration.

18.
Free Radic Biol Med ; 154: 119-131, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32437928

RESUMEN

Berries are rich sources of (poly)phenols which have been associated with the prevention of cardiovascular diseases in animal models and in human clinical trials. Recently, a berry enriched diet was reported to decrease blood pressure and attenuate kidney disease progression on Dahl salt-sensitive rats. However, the relationship between kidney function, metabolism and (poly)phenols was not evaluated. We hypothesize that berries promote metabolic alterations concomitantly with an attenuation of the progression of renal disease. For that, kidney and urinary metabolomic changes induced by the berry enriched diet in hypertensive rats (Dahl salt-sensitive) were analyzed using liquid chromatography (UPLC-MS/MS) and 1H NMR techniques. Moreover, physiological and metabolic parameters, and kidney histopathological data were also collected. The severity of the kidney lesions promoted in Dahl rats by a high salt diet was significantly reduced by berries, namely a decrease in sclerotic glomeruli. In addition, was observed a high urinary excretion of metabolites that are indicators of alterations in glycolysis/gluconeogenesis, citrate cycle, and pyruvate metabolism in the salt induced-hypertensive rats, a metabolic profile counteracted by berries consumption. We also provide novel insights that relates (poly)phenols consumption with alterations in cysteine redox pools. Cysteine contribute to the redox signaling that is normally disrupted during kidney disease onset and progression. Our findings provide a vision about the metabolic responses of hypertensive rats to a (poly)phenol enriched diet, which may contribute to the understanding of the beneficial effects of (poly)phenols in salt-induced hypertension.


Asunto(s)
Frutas , Hipertensión , Animales , Presión Sanguínea , Cromatografía Liquida , Hipertensión/metabolismo , Riñón/metabolismo , Metaboloma , Ratas , Ratas Endogámicas Dahl , Espectrometría de Masas en Tándem
19.
Neuroimage ; 47(4): 1711-9, 2009 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-19371786

RESUMEN

Steady state auditory evoked potentials (SSAEPs) in the electroencephalogram (EEG) and magnetoencephalogram (MEG) have been reported to be reduced in schizophrenia, most consistently to frequencies in the gamma range (40 Hz and greater). The current study evaluated the specificity of this deficit over a broad range of stimulus frequencies and harmonics, the relationship between phase locking and signal power, and whether induced 40 Hz activity was also affected. SSAEPs to amplitude modulated tones from 5 to 50 Hz were obtained from subjects with schizophrenia (SZ) and healthy control subjects in 5 Hz steps. Time-frequency spectral analysis was used to differentiate EEG activity synchronized in phase across trials using Phase Locking Factor (PLF) and Mean Power (MP) change from baseline activity. In the SSAEP frequency response condition, patients with SZ showed broad band reductions in both PLF and MP. In addition, the control subjects showed a more pronounced increase in PLF with increases in power compared to SZ subjects. A noise pulse embedded in 40 Hz stimuli resulted in a transient reduction of PLF and MP at 40 Hz in control subjects, while SZ showed diminished overall PLF. Finally, induced gamma (around 40 Hz) response to unmodulated tone stimuli was also reduced in SZ, indicating that disturbances in this oscillatory activity are not confined to SSAEPs. In summary, SZ subjects show impaired oscillatory responses in the gamma range across a wide variety of experimental conditions. Reduction of PLF along with reduced MP may reflect abnormalities in the auditory cortical circuits, such as a reduction in pyramidal cell volume, spine density and alterations in GABAergic neurons.


Asunto(s)
Estimulación Acústica/métodos , Corteza Auditiva/fisiopatología , Mapeo Encefálico/métodos , Electroencefalografía/métodos , Potenciales Evocados Auditivos , Esquizofrenia/diagnóstico , Esquizofrenia/fisiopatología , Adulto , Relojes Biológicos , Femenino , Humanos , Masculino
20.
Science ; 289(5482): 1150-1, 2000 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-10970229

RESUMEN

Many of the intricate pathways of apoptosis that instruct a cell to kill itself involve the convergence of key proteins on the membranes of mitochondria. Such proteins induce the permeabilization of mitochondrial membranes and the release of caspase enzymes and nuclease activators that set in motion the final stages of programmed cell death. Now, as Brenner and Kroemer discuss in their Perspective, a proapoptotic transcription factor called TR3 has been found to move from its normal location in the nucleus to the mitochondria and to promote release of cytochrome c, a key event in apoptosis (Li et al.)


Asunto(s)
Apoptosis , Proteínas de Unión al ADN/metabolismo , Membranas Intracelulares/metabolismo , Mitocondrias/metabolismo , Factores de Transcripción/metabolismo , Animales , Núcleo Celular/metabolismo , Grupo Citocromo c/metabolismo , ADN/metabolismo , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Regulación de la Expresión Génica , Humanos , Membranas Intracelulares/fisiología , Ratones , Ratones Transgénicos , Factor de Crecimiento Nervioso/farmacología , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares , Permeabilidad , Estructura Terciaria de Proteína , Receptores Citoplasmáticos y Nucleares , Receptores de Esteroides , Elementos de Respuesta , Transducción de Señal , Linfocitos T/citología , Linfocitos T/inmunología , Factores de Transcripción/química , Factores de Transcripción/genética , Dedos de Zinc
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