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1.
J Med Case Rep ; 15(1): 176, 2021 Mar 30.
Article in English | MEDLINE | ID: mdl-33781336

ABSTRACT

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.


Subject(s)
Mastocytosis, Cutaneous , Mastocytosis , Aged , Female , Humans , Mastocytosis/complications , Mastocytosis/diagnosis , Mastocytosis/drug therapy , Pruritus , Quality of Life , Skin
2.
Sci Rep ; 10(1): 13450, 2020 Aug 10.
Article in English | MEDLINE | ID: mdl-32778767

ABSTRACT

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.

3.
Ann Chir Plast Esthet ; 64(5-6): 575-582, 2019 Nov.
Article in French | MEDLINE | ID: mdl-31262440

ABSTRACT

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.


Subject(s)
Mammaplasty/adverse effects , Postoperative Complications/etiology , Postoperative Complications/therapy , Female , Humans , Postoperative Complications/prevention & control
4.
Pain Res Manag ; 2018: 8269564, 2018.
Article in English | MEDLINE | ID: mdl-29808107

ABSTRACT

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.


Subject(s)
Anxiety/etiology , Depression/etiology , Fibromyalgia/complications , Fibromyalgia/psychology , Stereotyping , Adult , Female , Humans , Longitudinal Studies , Middle Aged , Pain Measurement , Psychiatric Status Rating Scales , Retrospective Studies , Self Report , Stress, Psychological , Surveys and Questionnaires , Visual Analog Scale
5.
Phys Rev Lett ; 117(23): 235002, 2016 Dec 02.
Article in English | MEDLINE | ID: mdl-27982626

ABSTRACT

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.

6.
Vaccine ; 34(37): 4378-85, 2016 08 17.
Article in English | MEDLINE | ID: mdl-27452864

ABSTRACT

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.


Subject(s)
AIDS Vaccines/immunology , HIV Antigens/immunology , Immunogenicity, Vaccine , T-Lymphocytes/immunology , Adenoviridae , Animals , Female , Haplotypes , Interferon-gamma/immunology , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Inbred CBA , Pan troglodytes , Transgenes , gag Gene Products, Human Immunodeficiency Virus/immunology , nef Gene Products, Human Immunodeficiency Virus/immunology , pol Gene Products, Human Immunodeficiency Virus/immunology
7.
Vaccine ; 33(51): 7283-7289, 2015 Dec 16.
Article in English | MEDLINE | ID: mdl-26546736

ABSTRACT

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.


Subject(s)
AIDS Vaccines/immunology , Adenoviruses, Simian/immunology , Drug Carriers , T-Lymphocytes/immunology , gag Gene Products, Human Immunodeficiency Virus/immunology , nef Gene Products, Human Immunodeficiency Virus/immunology , pol Gene Products, Human Immunodeficiency Virus/immunology , AIDS Vaccines/administration & dosage , AIDS Vaccines/genetics , Adenoviruses, Simian/genetics , Animals , Enzyme-Linked Immunospot Assay , Female , Genetic Vectors , Interferon-gamma/metabolism , Mice, Inbred C57BL , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/genetics , Vaccines, Synthetic/immunology , gag Gene Products, Human Immunodeficiency Virus/genetics , nef Gene Products, Human Immunodeficiency Virus/genetics , pol Gene Products, Human Immunodeficiency Virus/genetics
8.
Phys Rev Lett ; 111(18): 185001, 2013 Nov 01.
Article in English | MEDLINE | ID: mdl-24237527

ABSTRACT

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.

9.
Phys Rev Lett ; 108(14): 145003, 2012 Apr 06.
Article in English | MEDLINE | ID: mdl-22540800

ABSTRACT

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.

10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 85(1 Pt 2): 016403, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22400684

ABSTRACT

Two-plasmon-decay (TPD) instability is investigated for conditions relevant for the shock-ignition (SI) scheme of inertial confinement fusion. Two-dimensional particle-in-cell simulations show that in a hot, large-scale plasma, TPD develops in concomitance with stimulated Raman scattering (SRS). It is active only during the first picosecond of interaction, and then it is rapidly saturated due to plasma cavitation. TPD-excited plasma waves extend to small wavelengths, above the standard Landau cutoff. The hot electron spectrum created by SRS and TPD is relatively soft, limited to energies below 100 keV, which should not be a danger for the fuel core preheat in the SI scenario.

11.
Phys Rev E Stat Nonlin Soft Matter Phys ; 82(1 Pt 2): 016408, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20866748

ABSTRACT

The expansion of a plasma slab into a vacuum is studied using one-dimensional and two-dimensional particle-in-cell simulations. As electrons transfer their longitudinal kinetic energy to ions during the expansion, the electron temperature becomes anisotropic. Once this anisotropy exceeds a threshold value, it drives the Weibel instability, leading to magnetic fields in the megagauss range. These fields induce energy transfer between the longitudinal and transverses directions, which influences the expansion. The impact of a cold electron population on this phenomenon is also investigated.

12.
Phys Rev E Stat Nonlin Soft Matter Phys ; 82(2 Pt 2): 026408, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20866927

ABSTRACT

The development of the Weibel instability during the expansion of a thin plasma foil heated by an intense laser pulse is investigated, using both analytical models and relativistic particle-in-cell simulations. When the plasma has initially an anisotropic electron distribution, this electromagnetic instability develops from the beginning of the expansion. Then it contributes to suppress the anisotropy and eventually saturates. After the saturation, the strength of the magnetic field decreases because of the plasma expansion until it becomes too weak to maintain the distribution isotropic. For this time, the anisotropy rises as electrons give progressively their longitudinal energy to ions, so that a new instability can develop.

13.
Phys Rev Lett ; 104(2): 025001, 2010 Jan 15.
Article in English | MEDLINE | ID: mdl-20366602

ABSTRACT

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.

14.
Phys Rev Lett ; 102(18): 185003, 2009 May 08.
Article in English | MEDLINE | ID: mdl-19518880

ABSTRACT

We report on highly time- and space-resolved measurements of the evolution of electron plasma waves driven by stimulated Raman scattering of a picosecond, single laser speckle propagating through a preformed underdense plasma. Two-dimensional Thomson scatter spectra indicate that the dominant waves have significant transverse components. These results are supported by particle-in-cell simulations which pinpoint the dominant role of the wave front bowing and of secondary nonlinear electrostatic instabilities in the evolution of the plasma waves.

15.
Phys Rev E Stat Nonlin Soft Matter Phys ; 77(6 Pt 2): 066407, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18643383

ABSTRACT

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.

16.
Brain Pathol ; 18(1): 1-9, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17924984

ABSTRACT

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.


Subject(s)
Histamine/metabolism , Hypoxia-Ischemia, Brain/metabolism , Mast Cells/metabolism , Nerve Degeneration/metabolism , Stroke/metabolism , Age Factors , Animals , Animals, Newborn , Biomarkers/analysis , Biomarkers/metabolism , Brain/blood supply , Brain/metabolism , Brain/pathology , Cell Count , Cell Death , Chemotaxis, Leukocyte , Disease Models, Animal , Histamine Release , Hypoxia-Ischemia, Brain/pathology , Infarction, Middle Cerebral Artery/pathology , Microtubule-Associated Proteins/metabolism , Nerve Degeneration/etiology , Nerve Degeneration/pathology , Rats , Reperfusion Injury/metabolism , Reperfusion Injury/pathology , Stroke/pathology , Time Factors
17.
Transfus Clin Biol ; 14(4): 393-401, 2007 Oct.
Article in French | MEDLINE | ID: mdl-17632027

ABSTRACT

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.


Subject(s)
Blood Banks/standards , Erythrocyte Transfusion/standards , Erythrocytes/cytology , Apoptosis , Cell Survival , Erythrocyte Membrane/physiology , Erythrocytes/physiology , Flow Cytometry , France , Hemoglobins/metabolism , Humans , Phagocytosis
18.
Phys Rev Lett ; 97(20): 205006, 2006 Nov 17.
Article in English | MEDLINE | ID: mdl-17155691

ABSTRACT

We study the angular distribution of relativistic electrons generated through laser-plasma interaction with pulse intensity varying from 10(18) W/cm2 up to 10(21) W/cm2 and plasma density ranging from 10 times up to 160 times critical density with the help of 2D and 3D particle-in-cell simulations. This study gives clear evidence that the divergence of the beam is an intrinsic property of the interaction of a laser pulse with a sharp density gradient. It is entirely due to the excitation of large static magnetic fields in the layer of interaction. The energy deposited in this layer increases drastically the temperature of the plasma independently of the initial temperature. This makes the plasma locally collisionless and the simulation relevant for the current experiments.

19.
Phys Rev Lett ; 97(1): 015001, 2006 Jul 07.
Article in English | MEDLINE | ID: mdl-16907380

ABSTRACT

The excitation and the relaxation of the plasma waves and ion acoustic waves (IAW), respectively, driven by stimulated Raman (SRS) and Brillouin (SBS) backscatterings have been experimentally investigated with short-pulse lasers. The spectra have been obtained with a 0.3 ps time resolution. It is shown that SRS develops before SBS and suddenly decays around the peak of the pump, as the IAW reaches saturation. On this short time scale, electron kinetic effects play a major role for SRS saturation, contrary to ion dynamics. These results are supported by particle-in-cell simulations.

20.
Phys Rev Lett ; 94(5): 055003, 2005 Feb 11.
Article in English | MEDLINE | ID: mdl-15783655

ABSTRACT

The electron kinetic effects are shown to play an important role in the nonlinear evolution of a driven ion-acoustic wave. The numerical simulation results obtained (i) with a hybrid code, in which the electrons behave as a fluid and the ions are described along the particle-in-cell (PIC) method, are compared with those obtained (ii) with a full-PIC code, in which the kinetic effects on both species are retained. The electron kinetic effects interplay with the usual fluid-type nonlinearity to give rise to a broadband spectrum of ion-acoustic waves saturated at a low level, even in the case of a strong excitation. This low asymptotic level might solve the long-standing problem of the small stimulated Brillouin scattering reflectivity observed in laser-plasma interaction experiments.

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