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1.
J Chem Phys ; 160(10)2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38456531

RESUMEN

We present cross sections for the formation of positronium chloride (PsCl) in its ground state from the charge exchange between positronium (Ps) and chloride (Cl-) in the range of 10 meV-100 eV Ps energy. We have used theoretical models based on the first Born approximation in its three-body formulation. We simulated the collisions between Ps and Cl- using ab initio binding energies and positronic wave functions at both the mean-field and correlated levels extrapolated to the complete basis set limit. The accuracy of these ab initio data was benchmarked on the PsF system with the existing highly accurate results, including the very recent quantum Monte Carlo results. We have investigated Ps excited states up to n = 4. The results suggest that the channel Ps(n = 2) is of particular interest for the production of PsCl in the ground state and shows that an accurate treatment of correlation effects (i.e., electron-electron and electron-positron correlations) leads to a significant change in the magnitude of the PsCl production cross section with respect to the mean-field level.

3.
Sci Rep ; 9(1): 17873, 2019 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-31784539

RESUMEN

Fermionization is what happens to the state of strongly interacting repulsive bosons interacting with contact interactions in one spatial dimension. Crystallization is what happens for sufficiently strongly interacting repulsive bosons with dipolar interactions in one spatial dimension. Crystallization and fermionization resemble each other: in both cases - due to their repulsion - the bosons try to minimize their spatial overlap. We trace these two hallmark phases of strongly correlated one-dimensional bosonic systems by exploring their ground state properties using the one- and two-body density matrix. We solve the N-body Schrödinger equation accurately and from first principles using the multiconfigurational time-dependent Hartree for bosons (MCTDHB) and for fermions (MCTDHF) methods. Using the one- and two-body density, fermionization can be distinguished from crystallization in position space. For N interacting bosons, a splitting into an N-fold pattern in the one-body and two-body density is a unique feature of both, fermionization and crystallization. We demonstrate that this splitting is incomplete for fermionized bosons and restricted by the confinement potential. This incomplete splitting is a consequence of the convergence of the energy in the limit of infinite repulsion and is in agreement with complementary results that we obtain for fermions using MCTDHF. For crystalline bosons, in contrast, the splitting is complete: the interaction energy is capable of overcoming the confinement potential. Our results suggest that the spreading of the density as a function of the dipolar interaction strength diverges as a power law. We describe how to distinguish fermionization from crystallization experimentally from measurements of the one- and two-body density.

4.
Leukemia ; 29(6): 1267-78, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25482131

RESUMEN

The canonical wingless-type MMTV integration site (WNT)-ß-catenin pathway is essential for self-renewal, growth and survival of acute myeloid leukemia (AML) stem/blast progenitor cells (BPCs). Deregulated WNT signaling inhibits degradation of ß-catenin, causing increased nuclear translocation and co-factor activity of ß-catenin with the transcriptional regulator T-cell factor (TCF) 4/lymphoid enhancer factor 1 in AML BPCs. Here, we determined the pre-clinical anti-AML activity of the anthraquinone oxime-analog BC2059 (BC), known to attenuate ß-catenin levels. BC treatment disrupted the binding of ß-catenin with the scaffold protein transducin ß-like 1 and proteasomal degradation and decline in the nuclear levels of ß-catenin. This was associated with reduced transcriptional activity of TCF4 and expression of its target genes, cyclin D1, c-MYC and survivin. BC treatment dose-dependently induced apoptosis of cultured and primary AML BPCs. Treatment with BC also significantly improved the median survival of immune-depleted mice engrafted with either cultured or primary AML BPCs, exhibiting nuclear expression of ß-catenin. Co-treatment with the pan-histone deacetylase inhibitor panobinostat and BC synergistically induced apoptosis of cultured and primary AML BPCs, including those expressing FLT3-ITD, as well as further significantly improved the survival of immune-depleted mice engrafted with primary AML BPCs. These findings underscore the promising pre-clinical activity and warrant further testing of BC against human AML, especially those expressing FLT3-ITD.


Asunto(s)
Antineoplásicos/farmacología , Sinergismo Farmacológico , Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas/química , Leucemia Mieloide Aguda/tratamiento farmacológico , beta Catenina/antagonistas & inhibidores , Animales , Protocolos de Quimioterapia Combinada Antineoplásica , Apoptosis/efectos de los fármacos , Western Blotting , Proliferación Celular/efectos de los fármacos , Histona Desacetilasas/metabolismo , Humanos , Inmunoprecipitación , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patología , Ratones , Ratones Desnudos , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto , beta Catenina/metabolismo
5.
Gynecol Obstet Fertil ; 42(10): 668-73, 2014 Oct.
Artículo en Francés | MEDLINE | ID: mdl-25245841

RESUMEN

OBJECTIVES: Evaluate the fiability and feasibility of laparoscopic surgery for the management of uterine cancers [endometrial cancer (EC) and early-stage cervical cancer (ESCC)] with patients who have a BMI ≤ 30 kg/m(2), within the setting of a gynaecological oncology department. PATIENTS AND METHODS: This retrospective, monocentric and descriptive study was carried out between January 2003 and May 2011 at the Institute Claudius-Regaud, a centre for cancer diagnosis, treatment and research. A policy promoting laparoscopy as a first choice treatment has been established at the institute since 2003. RESULTS: Two hundred and three patients were included. Eighty-five patients were early-stage cervical cancer patients and 118 patients were endometrial cancer patients. The study shows a high fiability rate for laparoscopy in non-obese patients, with a 98.8% rate for EC patients and a 98.8% rate for ESCC patients. The feasibility rates were 80.1% and 96.6%, respectively. The incidence of laparoconversion was reported at 1.2% and 3.1% for ESCC and EC patients, respectively, while the incidence of peroperative complications was 5.9% and 7.4%. The incidence of postoperative complications rank ≥ 3 according to "Memorial secondary events grading system" was 3 (3.5%) for CCUP and 3 (2.5%) for CE. DISCUSSION AND CONCLUSION: The results of this study show high fiability and feasibility levels for the laparoscopic treatment of uterine cancers in non-obese patients. There is no need to implement the more expensive robotic-assisted surgery in this group of patients. Mastering advanced laparoscopic surgery remains a mainstay in gynaecologic oncology.


Asunto(s)
Peso Corporal , Laparoscopía , Neoplasias Uterinas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Endometriales/patología , Neoplasias Endometriales/cirugía , Estudios de Factibilidad , Femenino , Humanos , Complicaciones Intraoperatorias/epidemiología , Tiempo de Internación , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/cirugía
6.
Phys Rev Lett ; 111(10): 103201, 2013 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-25166663

RESUMEN

We simultaneously measured the momentum transferred to a free-floating molecular double slit and the momentum change of the atom scattering from it. Our experimental results are compared to quantum mechanical and semiclassical models. The results reveal that a classical description of the slits, which was used by Einstein in his debate with Bohr, provides a surprisingly good description of the experimental results, even for a microscopic system, if momentum transfer is not ascribed to a specific pathway but shared coherently and simultaneously between both.

7.
J Chem Phys ; 135(16): 164305, 2011 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-22047237

RESUMEN

The nonadiabatic photoinduced ring opening occurring in the two lowest excited singlet states of furan is investigated theoretically, using wave-packet propagation techniques. The underlying multidimensional potential energy surfaces (PESs) are obtained from ab initio computations, using the equation-of-motion coupled cluster method restricted to single and double excitations (EOM-CCSD), reported in earlier recent work [E. V. Gromov, A. B. Trofimov, F. Gatti, and H. Köppel, J. Chem. Phys. 133, 164309 (2010)]. Up to five nuclear degrees of freedom are considered in the quantum dynamical treatment. Four of them represent in-plane motion for which the electronic states in question (correlating with the valence (1)B(2)(V) and Rydberg (1)A(2)(3s) states at the C(2v) ground-state molecular configuration) have different symmetries, A(') and A(''), respectively. The fifth mode, representing out-of-plane bending of the oxygen atom against the carbon-atom plane, leads to an interaction of these states, as is crucial for the photoreaction. The nonadiabatic coupling and conical intersection cause an electronic population transfer on the order of ∼10 fs. Its main features, and that of the wave-packet motion, are interpreted in terms of properties of the PES. The lifetime due to the ring-opening process has been estimated to be around 2 ps. The dependence of this estimate on the nuclear degrees of freedom retained in the computations is discussed.


Asunto(s)
Furanos/química , Ciclización , Procesos Fotoquímicos , Teoría Cuántica
8.
Arch Pediatr ; 18(3): 324-30, 2011 Mar.
Artículo en Francés | MEDLINE | ID: mdl-21257296

RESUMEN

This review concentrates on the best evidence emerging in recent years on cerebral palsy prevention by administration of magnesium sulfate in mothers at risk of pre-term birth before 33-34 weeks' gestation. It was shown in the Cochrane database and in 3 meta-analyses of 5 randomized trials (Magpie Trial [neuroprotection of the pre-eclamptic mother], MagNet [neuroprotection/other intent: tocolysis], ActoMgSO(4) [neuroprotection], PreMag [neuroprotection], and Beam [neuroprotection]) that prenatal low-dose magnesium sulfate given to mothers at risk of pre-term birth has no severe deleterious effects in mothers and does not increase pediatric mortality in very pre-term infants. Moreover, it has significant neuroprotective effects on the occurrence of cerebral palsy at 2 years of age (relative risk, 0.69; 95% confidence interval, 0.54-0.87) and, in the neuroprotection subgroup, on the combined outcome of pediatric mortality or cerebral palsy (relative risk: 0.85; 95% confidence interval: 0.74-0.98). The number needed to treat (NTT) to prevent 1 case of cerebral palsy was 63 (95% CI, 39-172) and the NTT for an extra survivor free of cerebral palsy in the neuroprotection subgroup was 42 (95% CI, 22-357), justifying that magnesium sulfate should be discussed as a stand-alone treatment or as part of a combination treatment.


Asunto(s)
Parálisis Cerebral/prevención & control , Sulfato de Magnesio/uso terapéutico , Fármacos Neuroprotectores/uso terapéutico , Animales , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro , Metaanálisis como Asunto , Modelos Animales , Trabajo de Parto Prematuro/prevención & control , Embarazo , Ensayos Clínicos Controlados Aleatorios como Asunto
9.
Theriogenology ; 75(3): 577-83, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21074835

RESUMEN

Sperm concentration assessment is a key point to insure appropriate sperm number per dose in species subjected to artificial insemination (AI). The aim of the present study was to evaluate the accuracy and reliability of two commercially available photometers, AccuCell™ and AccuRead™ pre-calibrated for boar semen in comparison to UltiMate™ boar version 12.3D, NucleoCounter SP100 and Thoma hemacytometer. For each type of instrument, concentration was measured on 34 boar semen samples in quadruplicate and agreement between measurements and instruments were evaluated. Accuracy for both photometers was illustrated by mean of percentage differences to the general mean. It was -0.6% and 0.5% for Accucell™ and Accuread™ respectively, no significant differences were found between instrument and mean of measurement among all equipment. Repeatability for both photometers was 1.8% and 3.2% for AccuCell™ and AccuRead™ respectively. Low differences were observed between instruments (confidence interval 3%) except when hemacytometer was used as a reference. Even though hemacytometer is considered worldwide as the gold standard, it is the more variable instrument (confidence interval 7.1%). The conclusion is that routine photometry measures of raw semen concentration are reliable, accurate and precise using AccuRead™ or AccuCell™. There are multiple steps in semen processing that can induce sperm loss and therefore increase differences between theoretical and real sperm numbers in doses. Potential biases that depend on the workflow but not on the initial photometric measure of semen concentration are discussed.


Asunto(s)
Análisis de Semen/veterinaria , Recuento de Espermatozoides/veterinaria , Porcinos , Animales , Calibración/normas , Masculino , Fotometría/instrumentación , Fotometría/veterinaria , Reproducibilidad de los Resultados , Análisis de Semen/instrumentación , Análisis de Semen/métodos , Recuento de Espermatozoides/instrumentación , Recuento de Espermatozoides/métodos
10.
Ann Dermatol Venereol ; 137(4): 285-9, 2010 Apr.
Artículo en Francés | MEDLINE | ID: mdl-20417362

RESUMEN

BACKGROUND: Primary effusion lymphoma (PEL) is a highly malignant non-Hodgkin lymphoma associated with Kaposi's sarcoma-associated herpesvirus/human herpesvirus-8 infection (KSHV/HHV-8). It is chiefly seen in HIV patients and is rare in transplant recipients, possibly going unrecognized. OBSERVATION: We describe two male kidney transplant recipients, aged 47 and 51 years, followed for Kaposi's sarcoma in skin, lymph nodes, gastrointestinal (GI) tract and lung whose disease was poorly controlled by sirolimus and chemotherapy. Recurrent pleural effusion contrasted with reduction of cutaneous Kaposi lesions. KHSV viral loads were negative or very low in plasma, were negative or very low, whereas those in pleural effusion were high. Lymphoma cells were discovered only seven to nine months after the initial effusion despite repeated needle biopsies. In one patient, tumour cells were co-infected with Epstein-Barr virus. CONCLUSION: The contrast between a very low KHSV viral load in plasma and a very high viral load pleural effusion should alert physicians and prompt suspicion of PEL in Kaposi's sarcoma patients with recurrent serous effusion. The potential inhibitory role of sirolimus on PEL progression is discussed.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Infecciones por Virus de Epstein-Barr/etiología , Herpesvirus Humano 4/aislamiento & purificación , Herpesvirus Humano 8/aislamiento & purificación , Inmunosupresores/efectos adversos , Trasplante de Riñón , Linfoma de Efusión Primaria/etiología , Neoplasias Primarias Múltiples/etiología , Complicaciones Posoperatorias/etiología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Enfermedad de Castleman/complicaciones , Enfermedad de Castleman/virología , Neoplasias del Sistema Digestivo/tratamiento farmacológico , Neoplasias del Sistema Digestivo/secundario , Neoplasias del Sistema Digestivo/virología , Resultado Fatal , Humanos , Huésped Inmunocomprometido , Inmunosupresores/uso terapéutico , Fallo Renal Crónico/etiología , Fallo Renal Crónico/cirugía , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/secundario , Neoplasias Pulmonares/virología , Metástasis Linfática , Linfoma de Efusión Primaria/virología , Masculino , Persona de Mediana Edad , Neoplasias Primarias Múltiples/virología , Derrame Pleural Maligno/citología , Derrame Pleural Maligno/virología , Complicaciones Posoperatorias/virología , Sarcoma de Kaposi/tratamiento farmacológico , Sarcoma de Kaposi/etiología , Sarcoma de Kaposi/virología , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/etiología , Neoplasias Cutáneas/virología , Carga Viral
11.
Arch Pediatr ; 16(12): 1533-9, 2009 Dec.
Artículo en Francés | MEDLINE | ID: mdl-19854629

RESUMEN

UNLABELLED: There are few data examining the vaccine practices for 0- to 24-month-old premature infants born before 33 GW. The aim of the study was to examine the vaccine coverage in this population according to the French schedule at 6 and 24 months. RESULTS: Eighty-seven infants were included in this regional prospective study. The immunization program began late and was initialized principally with DTPCoqHib (63%), usually after the 4th month. Fewer than one infant out of two (45%) had received three doses by 6 months of age. At 2 years of age, the coverage was 99% at 3 doses and decreased to 83% for 4 doses. For the MMR vaccine, the average age of administration was after 15 months, and 95% of infants had received one dose of MMR at 2 years of age. BCG coverage at 2 years of age was 94%, administered on average at 7 months. Forty-seven percent of the infants had received at least one dose of hepatitis B vaccine before 2 years of age, but only 31% had received two doses and a booster at 2 years of age. The adaptation of vaccination practices basically concerns the initial date of vaccination, but the immunization calendar is not recovered at 2 years of age. This should be taken into account for pertussis disease prevention in these young infants during the first 6 months of life, increasing the susceptibility period for this infectious disease. DISCUSSION AND CONCLUSION: The vaccine practices do not follow the postnatal chronological age of the premature baby according to the schedule recommended for full-term infants and vaccination is begun late. Based on the CSHPF vaccination recommendations, nearly 7 premature infants out of 10 have an incomplete immunization status for DTPCoqHib, hepatitis B, and ROR at 2 years of age. According to the pertussis coverage observed in premature infants, the new recommendations on vaccination of the newborn's care giver and family should be completed before the infant's discharge from the hospital using a new acellular vaccine for adult immunization. The initiation of an immunization program during hospitalization would be beneficial for premature babies still hospitalized after 2 months of age.


Asunto(s)
Programas de Inmunización/estadística & datos numéricos , Recien Nacido Prematuro , Vacunación/estadística & datos numéricos , Vacuna BCG/administración & dosificación , Preescolar , Francia/epidemiología , Vacunas contra Hepatitis B/administración & dosificación , Humanos , Esquemas de Inmunización , Lactante , Recién Nacido , Vacuna contra el Sarampión-Parotiditis-Rubéola/administración & dosificación , Proyectos Piloto , Guías de Práctica Clínica como Asunto , Vacunas Combinadas/administración & dosificación
13.
BJOG ; 114(3): 310-8, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17169012

RESUMEN

OBJECTIVE: To evaluate whether magnesium sulphate (MgSO(4)) given to women at risk of very-preterm birth would be neuroprotective in preterm newborns and would prevent neonatal mortality and severe white-matter injury (WMI). DESIGN: A randomised study. SETTING: Eighteen French tertiary hospitals. Population Women with fetuses of gestational age < 33 weeks whose birth was planned or expected within 24 hours were enrolled from July 1997 to July 2003 with follow up of infants until hospital discharge. METHODS Five hundred and seventy-three mothers were randomly assigned to receive a single 40-ml infusion of 0.1 g/ml of MgSO(4) (4 g) solution or isotonic 0.9% saline (placebo) over 30 minutes. This study is registered as an International Standard Randomised Controlled Trial, number 00120588. MAIN OUTCOME MEASURES: The primary endpoints were rates of severe WMI or total mortality before hospital discharge, and their combined outcome. Analyses were based on intention to treat. RESULTS: After 6 years of enrolment, the trial was stopped. Data from 688 infants were analysed. Comparing infants who received MgSO(4) or placebo, respectively, total mortality (9.4 versus 10.4%; OR: 0.79, 95% CI 0.44-1.44), severe WMI (10.0 versus 11.7%; OR: 0.78, 95% CI 0.47-1.31) and their combined outcomes (16.5 versus 17.9%; OR: 0.86, 95% CI 0.55-1.34) were less frequent for the former, but these differences were not statistically significant. No major maternal adverse effects were observed in the MgSO(4) group. CONCLUSION: Although our results are inconclusive, improvements of neonatal outcome obtained with MgSO(4) are of potential clinical significance. More research is needed to assess the protective effect of MgSO(4) alone or in combination with other neuroprotective molecules.


Asunto(s)
Parálisis Cerebral/prevención & control , Leucomalacia Periventricular/prevención & control , Sulfato de Magnesio/administración & dosificación , Trabajo de Parto Prematuro/prevención & control , Tocolíticos/administración & dosificación , Adulto , Parálisis Cerebral/mortalidad , Femenino , Humanos , Mortalidad Infantil , Recién Nacido , Recien Nacido Prematuro , Infusiones Intravenosas , Leucomalacia Periventricular/mortalidad , Sulfato de Magnesio/efectos adversos , Embarazo , Resultado del Embarazo , Tocolíticos/efectos adversos
14.
Neurochirurgie ; 51(3-4 Pt 2): 323-8, 2005 Sep.
Artículo en Francés | MEDLINE | ID: mdl-16292176

RESUMEN

The localization of functional areas obtained from functional MRI (fMRI) is useful for patients suffering from tumors contiguous to eloquent brain areas. fRMI is an efficient tool in the strategy of treatment of low grade oligodendroglioamas in the rolandic area in intact or slightly impaired patients. It can be used preoperatively to assess motor functional areas. Indeed there is a good correlation for motor cortex lesions when using comparison between fMRI and intraoperative findings. Direct integration of fMRI data into neuronavigation enables to better visualize and preserve eloquent brain areas. One must be aware of fMRI limits. It is still often used with the control of direct cortical stimulations.


Asunto(s)
Neoplasias Encefálicas/fisiopatología , Imagen por Resonancia Magnética , Corteza Motora/fisiopatología , Oligodendroglioma/fisiopatología , Adulto , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/cirugía , Estudios de Factibilidad , Femenino , Humanos , Cuidados Intraoperatorios , Corteza Motora/diagnóstico por imagen , Corteza Motora/cirugía , Procedimientos Neuroquirúrgicos , Oligodendroglioma/diagnóstico por imagen , Oligodendroglioma/cirugía , Cuidados Preoperatorios , Lóbulo Temporal/diagnóstico por imagen , Lóbulo Temporal/fisiopatología , Lóbulo Temporal/cirugía , Tomografía Computarizada de Emisión de Fotón Único
16.
Arch Dis Child Fetal Neonatal Ed ; 89(2): F139-44, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-14977898

RESUMEN

OBJECTIVE: To evaluate the outcome for all infants born before 33 weeks gestation until discharge from hospital. DESIGN: A prospective observational population based study. SETTING: Nine regions of France in 1997. PATIENTS: All births or late terminations of pregnancy for fetal or maternal reasons between 22 and 32 weeks gestation. MAIN OUTCOME MEASURE: Life status: stillbirth, live birth, death in delivery room, death in intensive care, decision to limit intensive care, survival to discharge. RESULTS: A total of 722 late terminations, 772 stillbirths, and 2901 live births were recorded. The incidence of very preterm births was 1.3 per 100 live births and stillbirths. The survival rate for births between 22 and 32 weeks was 67% of all births (including stillbirths), 85% of live births, and 89% of infants admitted to neonatal intensive care units. Survival increased with gestational age: 31% of all infants born alive at 24 weeks survived to discharge, 78% at 28 weeks, and 97% at 32 weeks. Survival among live births was lower for small for gestational age infants, multiple births, and boys. Overall, 50% of deaths after birth followed decisions to withhold or withdraw intensive care: 66% of deaths in the delivery room, decreasing with increasing gestational age; 44% of deaths in the neonatal intensive care unit, with little variation with gestational age. CONCLUSION: Among very preterm babies, chances of survival varies greatly according to the length of gestation. At all gestational ages, a large proportion of deaths are associated with a decision to limit intensive care.


Asunto(s)
Mortalidad Infantil , Recien Nacido Prematuro , Peso al Nacer , Estudios de Cohortes , Femenino , Francia/epidemiología , Identidad de Género , Edad Gestacional , Humanos , Recién Nacido , Cuidado Intensivo Neonatal , Masculino , Progenie de Nacimiento Múltiple , Negativa al Tratamiento
17.
J Neuroradiol ; 30(1): 46-56, 2003 Jan.
Artículo en Francés | MEDLINE | ID: mdl-12624591

RESUMEN

Periventricular enhancement in adults at MRI is a significant finding since it often indicates the presence of an underlying disease requiring prompt medical attention. From a review of patients with periventricular enhancement, the main imaging features based on the underlying infectious or tumoral etiology will be described. The presented differential diagnosis is based on the immune status of the patient, type of enhancement, and response to a trial therapy. In immunocompromised patients, the main considerations are lymphoma and viral ependymitis. The pattern of enhancement is important. The presence of thin linear enhancement suggests a viral etiology (cytomegalovirus or varicella-zoster virus) that can be confirmed at CSF evaluation whereas the presence of nodular enhancement suggests a diagnosis of primary CNS lymphoma that can be confirmed by the presence of lymphomatous cells in the CSF or, more frequently, at stereotactic surgical biopsy performed after failure of response to anti-toxoplasmosis treatment. The presence of band enhancement is less specific and can be seen with viral, lymphomatous and even tuberculous involvement. In immunocompetent patients, a clinical context of infection will suggest bacterial or tuberculous ventriculitis and the presence of cystic lesions will suggest cysticercosis; in the absence of constitutional symptoms, the presence of nodular enhancement will suggest a tumoral process (lymphoma, ependymoma, germ cell tumor, or metastases). Rarely, linear enhancement will be due to sarcoidosis or Whipple's disease.


Asunto(s)
Epéndimo/patología , Imagen por Resonancia Magnética , Adulto , Anciano , Encefalopatías/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
18.
Neuroimage ; 18(2): 460-7, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12595199

RESUMEN

The value of functional MR Imaging (fMRI) in assessing language lateralization in epileptic patients candidate for surgical treatment is increasingly recognized. However few data are available for left-handed patients. Moreover determining factors for atypical dominance in patients investigated with contemporary imaging have not been reported. We studied 20 patients (14 males, 6 females; 9 right handed, 11 left handed) aged from 9 to 48 years, investigated for intractable partial epilepsy. Epileptic focus location was temporal in 14 cases, extratemporal in 6, and lateralized in the left hemisphere in 11/20. Hemispheric dominance for language was evaluated by both Wada test and fMRI using a silent word generation paradigm in all patients. Furthermore, a postictal speech test was performed in 15 patients. An fMRI language lateralization index was calculated from the number of activated pixels (Student's t test, P < 0.0001) in the right and left hemispheres. The Wada test showed a right hemispheric dominance in 8 patients (6 were left handed and 2 right handed) and a left hemispheric dominance in 12 patients (5 were left handed and 7 right handed). These results were concordant with clinical postictal examination in 11/15 patients (73%). Clinical status did not allow a conclusion about hemispheric dominance for the remaining 4 patients. FMRI was concordant with the Wada test in 19/20 cases. For one left-handed patient, fMRI showed bilateral activation, whereas the Wada test demonstrated a right hemispheric dominance. Right language lateralization was significantly correlated with left lateralized epilepsy (P < 0.05) but was not correlated with age at epilepsy onset, early brain injury (before 6 years), and lobar localization of epileptogenic focus. However the lack of a significant relationship between these factors and atypical language lateralization may be related to the small sample size.


Asunto(s)
Dominancia Cerebral/fisiología , Electroencefalografía , Epilepsia del Lóbulo Temporal/fisiopatología , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Lectura , Percepción del Habla/fisiología , Conducta Verbal/fisiología , Adolescente , Adulto , Amobarbital , Anomia/fisiopatología , Mapeo Encefálico , Niño , Femenino , Humanos , Pruebas del Lenguaje , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad
19.
Arch Pediatr ; 9(9): 907-12, 2002 Sep.
Artículo en Francés | MEDLINE | ID: mdl-12387171

RESUMEN

AIM: We studied the use of premixed nitrous oxide and oxygen in 80 patients with neurologic diseases. PATIENTS AND METHODS: Mean ages ranged 10 +/- 5 yrs. Twenty-three patients (29%) were mentally retardated among which 17 of them presented with severe epilepsy. Painful procedures consisted of: lumbar punctures (80%), intravenous access (7), gastric endoscopy (6), skin biopsy (4), gastrostomy tube management (3). High-risk children were continuously monitored using ECG, non invasive blood pressure and transcutaneous oxygen saturation. We studied acceptation of the inhalation, vital signs, satisfaction of children, parents, medical and nursing staffs; side effects were compared with a group of healthy children undergoing venous access before induction of anesthesia. RESULTS AND DISCUSSION: Acceptation increased with age. No significant changes in vital signs variables were observed. Satisfaction rate regarding the method was 88% for all children, parents, physicians and nurses. No serious undesirable event (as respiratory depression, seizure, inhalation of gastric content) occurred in these patients. The more frequent side-effects were: drowsiness during and after inhalation (35 and 9% respectively in the handicapped patients); nausea and vomiting (8%), headaches (3%), were more frequent than reported in literature but there were 25% of meningitis among our patients. CONCLUSION: Premixed nitrous oxide and oxygen was effective for reducing procedural pain and anxiety in children with neurological disorders, even in severely handicapped patients, with minor side-effects.


Asunto(s)
Sedación Consciente/métodos , Nitrógeno/uso terapéutico , Oxígeno/uso terapéutico , Dolor/tratamiento farmacológico , Dolor/etiología , Administración por Inhalación , Adolescente , Adulto , Biopsia/efectos adversos , Cateterismo Periférico/efectos adversos , Niño , Preescolar , Sedación Consciente/efectos adversos , Sedación Consciente/psicología , Monitoreo de Drogas , Electrocardiografía , Femenino , Gastroscopía/efectos adversos , Gastrostomía/efectos adversos , Humanos , Discapacidad Intelectual/complicaciones , Masculino , Oximetría , Dolor/diagnóstico , Dolor/psicología , Dimensión del Dolor , Satisfacción del Paciente , Punción Espinal/efectos adversos , Resultado del Tratamiento
20.
J Neurotrauma ; 19(1): 53-60, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11852978

RESUMEN

Residual activation of the cortex was investigated in nine patients with complete spinal cord injury between T6 and L1 by functional magnetic resonance imaging (fMRI). Brain activations were recorded under four conditions: (1) a patient attempting to move his toes with flexion-extension, (2) a patient imagining the same movement, (3) passive proprio-somesthesic stimulation of the big toes without visual control, and (4) passive proprio-somesthesic stimulation of the big toes with visual control by the patient. Passive proprio-somesthesic stimulation of the toes generated activation posterior to the central sulcus in the three patients who also showed a somesthesic evoked potential response to somesthesic stimulation. When performed under visual control, activations were observed in two more patients. In all patients, activations were found in the cortical areas involved in motor control (i.e., primary sensorimotor cortex, premotor regions and supplementary motor area [SMA]) during attempts to move or mental imagery of these tasks. It is concluded that even several years after injury with some local cortical reorganization, activation of lower limb cortical networks can be generated either by the attempt to move, the mental evocation of the action, or the visual feedback of a passive proprio-somesthesic stimulation.


Asunto(s)
Imagen por Resonancia Magnética , Corteza Motora/fisiopatología , Corteza Somatosensorial/fisiopatología , Traumatismos de la Médula Espinal/fisiopatología , Adulto , Humanos , Imaginación/fisiología , Masculino , Persona de Mediana Edad , Plasticidad Neuronal/fisiología , Paraplejía/fisiopatología
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