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1.
Ann Chir Plast Esthet ; 64(5-6): 575-582, 2019 Nov.
Artículo en Francés | MEDLINE | ID: mdl-31262440

RESUMEN

Reduction mammoplasty is known to be a highly satisfactory surgery but complications and unfavorable results can occur. The objective was to describe the main unfavorable results, to specify their causes, preventions and treatments. We have analyzed articles from the last ten years regarding reduction mammoplasty complications as well as their main unfavorable results. The most common complications were wound dehiscence, hypertrophic scars, infections, fat necrosis, hematomas, and partial or total nipple-areolar complex necrosis. The most frequently reported unfavorable results were unaesthetic and retracted scars, asymmetry in breast size, abnormalities in shape, and malposition of the nipple-areolar complex. For each type of unfavorable outcomes, the possible causes, preventions and treatments were detailed.


Asunto(s)
Mamoplastia/efectos adversos , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/terapia , Femenino , Humanos , Complicaciones Posoperatorias/prevención & control
2.
Phys Rev Lett ; 117(23): 235002, 2016 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-27982626

RESUMEN

Experiments have been performed evidencing significant stimulated Raman sidescattering (SRS) at large angles from the density gradient. This was achieved in long scale-length high-temperature plasmas in which two beams couple to the same scattered electromagnetic wave further demonstrating for the first time this multiple-beam collective SRS interaction. The collective nature of the coupling and the amplification at large angles from the density gradient increase the global SRS losses and produce light scattered in novel directions out of the planes of incidence of the beams. These findings obtained in plasmas conditions relevant of inertial confinement fusion experiments similarly apply to the more complex geometry of these experiments where anomalously large levels of SRS were measured.

3.
Phys Rev Lett ; 111(18): 185001, 2013 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-24237527

RESUMEN

The interaction of laser pulses with thin grating targets, having a periodic groove at the irradiated surface, is experimentally investigated. Ultrahigh contrast (~10(12)) pulses allow us to demonstrate an enhanced laser-target coupling for the first time in the relativistic regime of ultrahigh intensity >10(19) W/cm(2). A maximum increase by a factor of 2.5 of the cutoff energy of protons produced by target normal sheath acceleration is observed with respect to plane targets, around the incidence angle expected for the resonant excitation of surface waves. A significant enhancement is also observed for small angles of incidence, out of resonance.

4.
Phys Rev Lett ; 108(14): 145003, 2012 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-22540800

RESUMEN

The autoresonant behavior of Langmuir waves excited by stimulated Raman scattering (SRS) is clearly identified in particle-in-cell (PIC) simulations in an inhomogeneous plasma. As previously shown via a 3-wave coupling model [T. Chapman et al., Phys. Plasmas 17, 122317 (2010)], weakly kinetic effects such as trapping can be described via an amplitude-dependent frequency shift that compensates the dephasing of the resonance of SRS due to the inhomogeneity. The autoresonance (AR) leads to phase locking and to growth of the Langmuir wave beyond the spatial amplification expected from Rosenbluth's model in an inhomogeneous profile [M. N. Rosenbluth, Phys. Rev. Lett. 29, 565 (1972)]. Results from PIC simulations and from a 3-wave coupling code show very good agreement, leading to the conclusion that AR arises even beyond the so-called weakly kinetic regime.

5.
J Med Case Rep ; 15(1): 176, 2021 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-33781336

RESUMEN

BACKGROUND: Cutaneous mastocytosis is a rare pathology characterized by an abnormal proliferation and degranulation of mast cells, affecting the skin. Here we present the case of a patient suffering from chronic resistant mastocytosis. An original integrative method of evaluation was tested in this patient, to improve therapeutic management. It integrated the interactions between stressful life events and medical history as well as psychobehavioral components and neurobiological factors. CASE PRESENTATION: The patient was a 65-year-old Caucasian woman. The cutaneous symptoms of mastocytosis had progressively evolved over the past 36 years, increasingly affecting the patient's quality of life. At the time of the evaluation, psoralen and ultraviolet A therapy had reduced pruritus, but very unsightly brown-red maculopapules persisted on the chest, back, and arms. We proposed an integrative diagnosis that combined a semistructured interview, a psychometric assessment with the Millon Behavioral Medicine Diagnostic tool, and the collection of medical data. The medical data were compared with the analysis of the significant events in the patient's life, to determine the threshold of tolerance to stress beyond which the skin symptoms led to profuse thrusts of pruritus. At the same time, the psychobehavioral profile of the patient was determined; this highlighted how social isolation, the denigrated coping style, and problematic compliance could influence the extension of dermatological symptoms. The effects of stressors on the infiltration and degranulation of skin mast cells have been discussed in light of the neurobiological processes currently known. At the end of the evaluation, a new therapeutic strategy was proposed. CONCLUSION: This case report reveals the mind-body relationship of a patient suffering from mastocytosis. It highlights the points of vulnerability and the adaptative strategies specific to each patient to be considered in therapeutic management of other resistant chronic diseases.


Asunto(s)
Mastocitosis Cutánea , Mastocitosis , Anciano , Femenino , Humanos , Mastocitosis/complicaciones , Mastocitosis/diagnóstico , Mastocitosis/tratamiento farmacológico , Prurito , Calidad de Vida , Piel
6.
Phys Rev Lett ; 104(2): 025001, 2010 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-20366602

RESUMEN

The energy transfer from a long (3.5 ps) pump pulse to a short (400 fs) seed pulse due to stimulated Brillouin backscattering in the strong-coupling regime is investigated. The two pulses, both at the same wavelength of 1.057 microm are quasicounterpropagating in a preformed underdense plasma. Relative amplification factors for the seed pulse of up to 32 are obtained. The maximum obtained amplified energy is 60 mJ. Simulations are in agreement with the experimental results and suggest paths for further improvement of the amplification scheme.

7.
Sci Rep ; 10(1): 13450, 2020 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-32778767

RESUMEN

The excitation of surface plasma waves (SPW) by an intense short laser pulse is a useful tool to enhance the laser absorption and the electron heating in the target. In this work, the influence of the transverse laser profile and the pulse duration used to excited SPW is investigated from Fluid and 2D Particle-in-Cell simulations. We show the existence of a lobe of surface plasma wave modes. Our results highlight surface plasma waves excitation mechanism and define the laser parameters to optimise the SPW excitation and the kinetic energy of the associated electron trapped in the wave. It opens the door to monitor the spectral mode distribution and temporal shape of the excited surface waves in the high relativistic regime. The most important result of the study is that-at least in 2D-the charge and the energy of the electron bunches depend essentially on the laser energy rather than on temporal or spatial shape of the laser pulse.

8.
Brain Pathol ; 18(1): 1-9, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17924984

RESUMEN

Inflammatory processes are a major cause of hypoxic-ischemic brain damage. The present study focuses on both the cerebral histamine system and mast cells in a model of transient focal ischemia induced by permanent left middle cerebral artery, and homolateral transient common carotid artery occlusion (50 minutes) in the P7 newborn rat. Immunohistochemical analysis revealed that ischemia induces histamine (HA) accumulation in the core of the infarct 6-12 h post-ischemia, and in the penumbra at 24-48 h, although in situ hybridization failed to detect any histidine decarboxylase gene transcripts in these regions. Immunohistochemical co-localization of HA with the MAP2 marker revealed that HA accumulates in neuronal cells before they degenerate, and is accompanied by a very significant increase in the number of mast cells at 12 h and 48 h of reperfusion. In mast cells, histamine immunoreactivity is detected at 2, 6 and 12 h after ischemia, whereas it disappears at 24 h, when a concomitant degranulation of mast cells is observed. Taken together, these data suggest that the recruitment of cerebral mast cells releasing histamine may contribute to ischemia-induced neuronal death in the immature brain.


Asunto(s)
Histamina/metabolismo , Hipoxia-Isquemia Encefálica/metabolismo , Mastocitos/metabolismo , Degeneración Nerviosa/metabolismo , Accidente Cerebrovascular/metabolismo , Factores de Edad , Animales , Animales Recién Nacidos , Biomarcadores/análisis , Biomarcadores/metabolismo , Encéfalo/irrigación sanguínea , Encéfalo/metabolismo , Encéfalo/patología , Recuento de Células , Muerte Celular , Quimiotaxis de Leucocito , Modelos Animales de Enfermedad , Liberación de Histamina , Hipoxia-Isquemia Encefálica/patología , Infarto de la Arteria Cerebral Media/patología , Proteínas Asociadas a Microtúbulos/metabolismo , Degeneración Nerviosa/etiología , Degeneración Nerviosa/patología , Ratas , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología , Accidente Cerebrovascular/patología , Factores de Tiempo
9.
Phys Rev E Stat Nonlin Soft Matter Phys ; 77(6 Pt 2): 066407, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18643383

RESUMEN

The one-dimensional expansion of a plasma slab is studied using a kinetic description of the electrons based on an adiabatic invariant. The distribution function of the electrons is determined at any time and any position. Solution of the Poisson equation then enables us to determine the electric potential and the ion acceleration. Special attention is devoted to the disassembly time of the plasma slab which appears shorter than expected, due to the distortion of the electron distribution function. The spatial structures of the ion and electron densities and velocities are presented, together with a prediction of the maximum ion velocity. The model is compared to particle-in-cell simulations and excellent agreement is found.

10.
Pain Res Manag ; 2018: 8269564, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29808107

RESUMEN

Fibromyalgia is a chronic widespread pain syndrome associated with chronic fatigue. Its pathogenesis is not clearly understood. This study presents subjective experiences and sensitivities reported by fibromyalgia patients, which should be considered in primary care to avoid medical nomadism, as well as stigmatization of the patients. The prevalence of significant characteristics was compared with others patients consulting at the same pain unit who suffer from rebel and disabling form of chronic migraine. Psychometric tests were anonymously completed by 78 patients of the Pain Unit (44 fibromyalgia patients and 34 migraine patients). Tests evaluated pain (Visual Analog scale), childhood traumas (Childhood Trauma Questionnaire), lack of parental affection, stressful life events (Holmes and Rahe Scale), anxiety and depression (Hospital Anxiety and Depression Scale), perceived hypersensitivity to 10 stimuli, and hyperactivity before illness. However, pain scores were comparable in the two groups, and the prevalence was significantly higher in fibromyalgia patients than in migraine patients for anxiety (81.8% versus 51.5%) and depression (57.1% versus 8.8%). Childhood physical abuses were more frequently reported in fibromyalgia than in migraine cases (25% versus 3%). Similarly, the feeling of lack of parental affection, subjective hypersensitivity to stress and stimuli (cold, moisture, heat, full moon, and flavors) or hyperactivity (ergomania), appeared as prominent features of fibromyalgia patients. Fibromyalgia patients considered themselves as being hypersensitive (mentally and physically) compared to migraine patients. They also have higher depression levels. Beyond somatic symptoms, precociously taking account of psychosocial and behavioral strategies would highly improve treatment efficiency of the fibromyalgia syndrome.


Asunto(s)
Ansiedad/etiología , Depresión/etiología , Fibromialgia/complicaciones , Fibromialgia/psicología , Estereotipo , Adulto , Femenino , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Dimensión del Dolor , Escalas de Valoración Psiquiátrica , Estudios Retrospectivos , Autoinforme , Estrés Psicológico , Encuestas y Cuestionarios , Escala Visual Analógica
11.
Transfus Clin Biol ; 14(4): 393-401, 2007 Oct.
Artículo en Francés | MEDLINE | ID: mdl-17632027

RESUMEN

UNLABELLED: In light of recent results on the mechanism of programmed cell death of human red blood cells (RBC), the aim of the present study was to solve the enigma of the rapid clearance of transfused RBCs. MATERIALS AND METHODS: We describe new criteria of RBC viability founded on the use of flow cytometry. They were applied, in association with the classical ones: ATP and hemolysis measurements, to RBCs stored in SAGM medium for 42 days. RESULTS AND CONCLUSIONS: Application of an original method of flow cytometric quantitation of in vitro erythrophagocytosis showed that an important proportion of stored RBCs were phagocytized although the following classical signals for phagocytosis were absent, i.e.: desialylation, phosphatidylserine exposure in the outer leaflet of the RBC membrane, loss of CD47 receptor, an antiphagocytosis signal. In addition, ATP was still present and hemolysis was very low. This enigma was solved by the use of scanning electron microscopy, which showed the disappearance of discocytes and the presence of an important proportion of spheroechinocytes, which are the phagocytable forms of RBCs. The mechanism of this dramatic morphological transformation remains to be elucidated.


Asunto(s)
Bancos de Sangre/normas , Transfusión de Eritrocitos/normas , Eritrocitos/citología , Apoptosis , Supervivencia Celular , Membrana Eritrocítica/fisiología , Eritrocitos/fisiología , Citometría de Flujo , Francia , Hemoglobinas/metabolismo , Humanos , Fagocitosis
12.
Vaccine ; 34(37): 4378-85, 2016 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-27452864

RESUMEN

In vivo vaccination studies are conventionally conducted in a single mouse strain with results, only reflecting responses to a single immunogenetic background. We decided to examine the immune response to an HIV transgene (gag, pol and nef fusion protein) in 3 strains of mice (CBA, C57BL/6 and BALB/c) to determine the spectrum of responses and in addition to determine whether the serotype of the adenoviral vector used (ChAd3 and ChAd63) impacted the outcome of response. Our results demonstrated that all three strains of mice responded to the transgene and that the magnitude of responses were different between the strains. The C57BL/6 strain showed the lowest range of responses compared to the other strains and, very few responses were seen to the same peptide pool in all three strains of mice. In CBA and BALB/c mice there were significant differences in IFNγ production dependent on the adenoviral vector used. Our results suggest that employing a single strain of mouse may underestimate the efficacy and efficiency of vaccine products.


Asunto(s)
Vacunas contra el SIDA/inmunología , Antígenos VIH/inmunología , Inmunogenicidad Vacunal , Linfocitos T/inmunología , Adenoviridae , Animales , Femenino , Haplotipos , Interferón gamma/inmunología , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Pan troglodytes , Transgenes , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/inmunología , Productos del Gen nef del Virus de la Inmunodeficiencia Humana/inmunología , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/inmunología
13.
Mech Dev ; 105(1-2): 167-73, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11429293

RESUMEN

Endogenous histamine is involved in tissue growth and cell proliferation. In accordance with a putative function of the H(3) receptor in this mitogenic effect, we show that H(3)-receptor mRNAs are expressed together with those of the histamine-synthesizing enzyme in the embryonic liver and adipose tissue, and in various epithelia. Finally, we show that activation of recombinant H(3) receptors enhances MAP kinase activity.


Asunto(s)
Receptores Histamínicos H3/biosíntesis , Tejido Adiposo/embriología , Animales , Animales Recién Nacidos , Hibridación in Situ , Ligandos , Hígado/embriología , Sistema de Señalización de MAP Quinasas , ARN Mensajero/metabolismo , Ratas , Ratas Wistar , Receptores Histamínicos/metabolismo , Proteínas Recombinantes/metabolismo
14.
Vaccine ; 33(51): 7283-7289, 2015 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-26546736

RESUMEN

Adenoviruses have been shown to be both immunogenic and efficient at presenting HIV proteins but recent trials have suggested that they may play a role in increasing the risk of HIV acquisition. This risk may be associated with the presence of pre-existing immunity to the viral vectors. Chimpanzee adenoviruses (chAd) have low seroprevalence in human populations and so reduce this risk. ChAd3 and chAd63 were used to deliver an HIV gag, pol and nef transgene. ELISpot analysis of T cell responses in mice showed that both chAd vectors were able to induce an immune response to Gag and Pol peptides but that only the chAd3 vector induced responses to Nef peptides. Although the route of injection did not influence the magnitude of immune responses to either chAd vector, the dose of vector did. Taken together these results demonstrate that chimpanzee adenoviruses are suitable vector candidates for the delivery of HIV proteins and could be used for an HIV vaccine and furthermore the chAd3 vector produces a broader response to the HIV transgene.


Asunto(s)
Vacunas contra el SIDA/inmunología , Adenovirus de los Simios/inmunología , Portadores de Fármacos , Linfocitos T/inmunología , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/inmunología , Productos del Gen nef del Virus de la Inmunodeficiencia Humana/inmunología , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/inmunología , Vacunas contra el SIDA/administración & dosificación , Vacunas contra el SIDA/genética , Adenovirus de los Simios/genética , Animales , Ensayo de Immunospot Ligado a Enzimas , Femenino , Vectores Genéticos , Interferón gamma/metabolismo , Ratones Endogámicos C57BL , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/genética , Vacunas Sintéticas/inmunología , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen nef del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/genética
15.
FEBS Lett ; 374(2): 195-8, 1995 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-7589533

RESUMEN

Partial cDNAs coding for each of the three human inter-alpha-trypsin inhibitor (ITI) heavy chains were expressed in a bacterial plasmid system and rabbits were immunised with the fusion peptides obtained. Despite the strong sequence homology of these chains, the antisera turned out to be highly specific in the analysis of corresponding mRNA translation products or partially digested serum ITI. Besides classical serum ITI members, their use in Western blotting made it possible to evidence an H3-related ITI form and a low-amount H1-related HC/bikunin component. The relative levels of ITI family members was further studied in baboon and foetal calf sera.


Asunto(s)
alfa-Globulinas/inmunología , Inhibidores de Tripsina/inmunología , alfa-Globulinas/química , alfa-Globulinas/genética , Animales , Anticuerpos/inmunología , Especificidad de Anticuerpos , ADN Complementario , Escherichia coli , Regulación de la Expresión Génica , Humanos , Inmunoquímica , Papio , Conejos , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/inmunología , Inhibidores de Tripsina/química , Inhibidores de Tripsina/genética
16.
Neuroscience ; 57(3): 545-54, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8309523

RESUMEN

In the hippocampus, glutamatergic pathways are altered following seizure activity or transient global ischemia, both pathological conditions leading to selective neuronal degeneration. Glutamatergic receptors, and notably alpha-amino-3-hydroxy-5-methyl-4-isoxazolopropionate (AMPA) receptors, a family of glutamate receptors involved in fast synaptic transmission and in the maintenance of synaptic potentiation may play an important role in the pathological outcome. AMPA receptors are assembled from GluR-A, GluR-B, GluR-C and GluR-D polypeptides which exist in flop and flip variants, the latter allowing larger glutamate responses. Using in situ hybridization techniques, we show that kainate-induced epilepsy provokes a rapid but transient increase (50%) of GluR-B flip mRNA levels in all subregions of the hippocampus (CA1, CA3, dentate gyrus). This early phase is followed by a second, persistent GluR-B flip increase in regions in which neurons are known to be seizure-resistant (i.e. CA1 an dentate gyrus) while a 35% decrease is observed in the vulnerable CA3 area. Following global ischemia, the levels of GluR-B flip and flop variants are dramatically reduced (90-100%), well before any morphological signs of cell death, in the subiculum and CA1, two areas known to be particularly sensitive to ischemic insult. In keeping with the properties of GluR flip variants, it is suggested that altered subunit stoichiometry may lead to long-lasting enhanced efficiency of fast synaptic transmission in the epileptic hippocampus. Since GluR-B containing receptors are Ca2+ impermeable, our results also suggest altered Ca2+ permeability in the vulnerable pyramidal neurons of areas CA3 and CA1 in the epileptic and ischemic hippocampi, respectively.


Asunto(s)
Isquemia Encefálica/metabolismo , Epilepsia/metabolismo , Receptores AMPA/metabolismo , Receptores de Glutamato/metabolismo , Animales , Secuencia de Bases , Isquemia Encefálica/inducido químicamente , Isquemia Encefálica/patología , Susceptibilidad a Enfermedades , Epilepsia/inducido químicamente , Epilepsia/patología , Hipocampo/metabolismo , Hipocampo/patología , Hibridación in Situ , Ácido Kaínico , Masculino , Datos de Secuencia Molecular , Neuronas/metabolismo , Sondas de Oligonucleótidos/genética , Ratas , Ratas Wistar , Receptores de Glutamato/genética , Distribución Tisular
17.
Neuroscience ; 114(1): 173-93, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12207964

RESUMEN

The detailed distribution of histamine H(3) receptor mRNAs in rat brain was analyzed by in situ hybridization using a 33P-labelled riboprobe and was combined for the first time with the detailed autoradiographic distribution of the receptor determined in the same animals with [(125)I]iodoproxyfan, a selective radioligand. The signals generated on adjacent brain sections by each probe were quantified and/or rated and were compared in order to identify neuronal populations expressing the receptor. In addition, the cellular localization of the transcripts within various brain structures was analyzed in sections dipped in a photographic emulsion. In the cerebral cortex, the strong mRNA expression in intermediate and deep layers indicates the presence of H(3) receptors on several types of neurons. The binding is dense except in layer V, suggesting that H(3) receptors are located on granule cells and apical dendrites of pyramidal cells. In addition to their localization on monoaminergic afferents, the dense binding in layer IV and strong mRNA expression in thalamic nuclei suggest the presence of heteroreceptors on thalamocortical projections. In the hippocampus, the strong mRNA expression but low binding in pyramidal layers of the CA1 and ventral CA3 fields suggest that H(3) receptors are abundant on efferent projections of pyramidal cells. In the dentate gyrus, some binding sites in the molecular layer may correspond to H(3) receptors synthesized in granule cells and coexpressed with H(1) and H(2) receptors in their dendrites. In the basal ganglia, H(3) receptors are highly expressed in the striatal complex and olfactory tubercles but not in islands of Calleja. Some of the striatal binding sites may correspond to presynaptic receptors present on afferents. The mRNAs in cortical layer V may encode for heteroreceptors on corticostriatal neurons. The presence of mRNAs in the substantia nigra pars compacta suggests that H(3) receptors are located upon nigrostriatal afferents. However, the absence of any signal in the ventral tegmental area indicates that some but not all dopaminergic neurons express H(3) receptors. In addition, the homogeneous mRNA expression within the caudate putamen and nucleus accumbens suggests that many striatal H(3) receptors are present on medium-sized, spiny projection neurons of both the direct and indirect movement pathways. In agreement, a dense binding, but low mRNA expression, is observed in external and internal pallidum and in substantia nigra pars reticulata. In the amygdala, the dense binding and mRNA expression indicate the presence of receptors on both afferents and projections. In the thalamus, the binding in some association nuclei may correspond to receptors present on neurons emanating from the deep cortical layers that strongly express the mRNAs, as well as receptors on the visual systems. However, the low binding and high mRNA expression in most nuclei indicate that many receptors are present upon thalamic projections. In the hypothalamus, the mRNA expression parallels the density of binding sites and is the highest in the tuberomammillary nucleus. Further investigation is needed to know if the dense binding and mRNA expression observed in other nuclei such as the paraventricular, ventromedial and medial tuberal nuclei correspond to pre- and/or postsynaptic receptors. mRNAs are also observed in several areas projecting to the tuberomammillary nucleus, such as the ventrolateral preoptic nucleus. In the lower brainstem, the high mRNA expression and very low binding in the locus coeruleus and raphe nuclei indicate that presynaptic rather than somatodendritic receptors regulate noradrenaline and serotonin release, respectively. A similar pattern in vestibular nuclei suggests that receptors located on projections account for the anti-vertigo properties of H(3) receptor antagonists. In the cerebellum, binding is hardly detectable but a strong mRNA expression is found in most, if not all, Purkinje cells as well as in several central cerebellar nuclei, suggesting the presence of H(3) receptors on efferent projections. The present study reports the first detailed quantification and/or rating of H(3) receptor mRNAs in the brain. The comparison, performed in the same animals, with the distribution of the H(3) receptor protein provides evidence for the presence of H(3) receptors on many neuronal perikarya, dendrites and projections. Although some localizations, mainly as auto- or heteroreceptors, are consistent with previous functional studies, the physiological role, if any, of most of these presynaptic or postsynaptic receptors remains to be established.


Asunto(s)
Encéfalo/metabolismo , Expresión Génica/fisiología , Histamina/metabolismo , Neuronas/metabolismo , ARN Mensajero/metabolismo , Receptores Histamínicos H3/genética , Animales , Sitios de Unión/genética , Encéfalo/citología , Mapeo Encefálico , Imidazoles , Hibridación in Situ , Masculino , Neuronas/citología , Sondas de Oligonucleótidos , Isoformas de Proteínas/genética , Ensayo de Unión Radioligante , Ratas , Ratas Wistar
18.
Phys Rev Lett ; 84(16): 3598-601, 2000 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-11019155

RESUMEN

The interaction of ultraintense laser beams with underdense plasma slabs has been investigated with two-dimensional particle-in-cell numerical simulations, showing a strong absorption and a correlatively low transmission. Energetic electrons in the multi-MeV range are produced. At very high intensities the plasma transparency is recovered. These results are interpreted in terms of the development of electron parametric instabilities in the self-consistently heated plasma.

19.
Neurochem Int ; 26(6): 593-9, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7670363

RESUMEN

It has been postulated that a reversal of glutamate reuptake ("uptake reverse") may contribute to glutamate release during cerebral ischemia. We tested this hypothesis by studying the effect of threo-3-hydroxy-DL-aspartic acid (THA), a glutamate uptake inhibitor, on extracellular glutamate accumulation measured by microdialysis during 4-vessel ischemia (20 min). The inhibitory effect of THA on sodium-dependent glutamate uptake was measured in vitro on rat hippocampal slices (Ki = 45 +/- 11 microM). We examined in vivo the effect of THA (400 microM in the dialysis solution) on the extracellular glutamate release from the rat hippocampus, during veratridine depolarization and ischemia. THA decreased the amount of glutamate appearing in the extracellular space during veratridine depolarization (61%). In contrast, the glutamate release induced by ischemia was not affected by THA. We conclude that a reversal of the sodium-dependent uptake contributes to an increase in extracellular glutamate during veratridine depolarization. In contrast, glutamate release occurring during ischemia is not mediated by uptake reverse.


Asunto(s)
Isquemia Encefálica/metabolismo , Ácido Glutámico/metabolismo , Inhibidores de la Captación de Neurotransmisores/farmacología , Veratridina/farmacología , Animales , Antibacterianos/farmacología , Ácido Aspártico/análogos & derivados , Ácido Aspártico/farmacología , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Técnicas In Vitro , Cinética , Masculino , Microdiálisis , Ratas , Ratas Wistar
20.
Neuroreport ; 6(7): 1041-4, 1995 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-7632891

RESUMEN

Thioperamide, an H3-receptor antagonist that enhances endogenous histamine release, induced c-fos mRNA expression and Fos-like immunoreactivity in magnocellular neurones of rat supraoptic and paraventricular nuclei. This response was prevented as a result of blockade of the H1 receptor, indicating that endogenous histamine is able to activate these magnocellular neurones via stimulation of this receptor.


Asunto(s)
Regulación de la Expresión Génica/fisiología , Genes fos/fisiología , Histamina/fisiología , Núcleo Hipotalámico Paraventricular/metabolismo , Núcleo Supraóptico/metabolismo , Animales , Secuencia de Bases , Regulación de la Expresión Génica/efectos de los fármacos , Antagonistas de los Receptores Histamínicos , Inmunohistoquímica , Hibridación in Situ , Masculino , Datos de Secuencia Molecular , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Núcleo Hipotalámico Paraventricular/citología , Núcleo Hipotalámico Paraventricular/efectos de los fármacos , Piperidinas/farmacología , Sondas ARN , ARN Mensajero/biosíntesis , Ratas , Ratas Wistar , Núcleo Supraóptico/citología , Núcleo Supraóptico/efectos de los fármacos
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