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1.
Eur Spine J ; 24(7): 1574-81, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25724685

RESUMEN

PURPOSE: The purpose of this study was to evaluate the inter- and intra-observer variability of the computerized radiologic measurements using Keops(®) and to determine the bias between the software and the standard paper measurement. METHODS: Four individuals measured all frontal and sagittal variables on the 30 X-rays randomly selected on two occasions (test and retest conditions). The Bland-Altman plot was used to determine the degree of agreement between the measurement on paper X-ray and the measurement using Keops(®) for all reviewers and for the two measures; the intraclass correlation coefficient (ICC) was calculated for each pair of analyses to assess interobserver reproducibility among the four reviewers for the same patient using either paper X-ray or Keops(®) measurement and finally, concordance correlation coefficient (rc) was calculated to assess intraobserver repeatability among the same reviewer for one patient between the two measure using the same method (paper or Keops(®)). RESULTS: The mean difference calculated between the two methods was minimal at -0, 4° ± 3.41° [-7.1; 6.4] for frontal measurement and 0.1° ± 3.52° [-6.7; 6.8] for sagittal measurement. Keops(®) has a better interobserver reproducibility than paper measurement for determination of the sagittal pelvic parameter (ICC = 0.9960 vs. 0.9931; p = 0.0001). It has a better intraobserver repeatability than paper for determination of Cobbs angle (rc = 0.9872 vs. 0.9808; p < 0.0001) and for pelvic parameter (rc = 0.9981 vs. 0.9953; p < 0.0001). CONCLUSIONS: We conclude that Keops(®) has no bias compared to the traditionally paper measurement, and moreover, the repeatability and the reproducibility of measurements with this method is much better than with similar standard radiologic measures done manually in both frontal and sagittal plane and that the use of this software can be recommended for clinical application. LEVEL OF EVIDENCE: Diagnostic, level III.


Asunto(s)
Huesos Pélvicos/diagnóstico por imagen , Escoliosis/diagnóstico por imagen , Programas Informáticos , Columna Vertebral/diagnóstico por imagen , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Radiografía , Reproducibilidad de los Resultados , Adulto Joven
2.
Science ; 198(4314): 289-91, 1977 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-17770501

RESUMEN

The Hermes satellite, a joint Canadian-American program, has been used to provide a communication channel between radio telescopes in West Virginia and Ontario, for very-long-baseline interferometry (VLBI). This system makes possible instantaneous correlation of the data as well as a sensitivity substantially better than that of earlier VLBI systems, by virtue of a broader observational bandwidth. With the use of a geostationary communications satellite it is possible to eliminate the tape recorders and the most troublesome part of the postobservational data processing. A further possibility is the development of a phase-coherent interferometer.

3.
Arch Pediatr ; 24(10): 1029-1035, 2017 Oct.
Artículo en Francés | MEDLINE | ID: mdl-28893487

RESUMEN

Scoliosis is an abnormal curvature of the spine. One or several curves of more than 10 degrees in the frontal plane can be seen with the rotation of vertebrae in the axial plane, which modifies sagittal curves. In addition to esthetic harm, the morbidity of a scoliosis depends on the extent of the deformation. Treatment, whether it be orthopedic or surgical, is aggressive and never completely cures the condition. At best the deformation will be stabilized at the end of growth. Therefore, it is essential to detect any slight curve and quickly identify any potential progressive form in order to treat it. Visualization of scoliosis in 3D through spine modeling has several advantages at each stage of care. First, with slight curvatures, 3D modeling allows the medical staff to confirm the scoliosis by showing the modification in the three different planes. All curvatures will not progress. Orthopedic treatment is constraining and expensive; only progressive forms will receive it. When the curvature is slight and does not need immediate treatment, 3D modeling at each successive check-up will help detect any sign of likely progression quickly and reliably. Moreover, the medical observation of corset treatment and the preoperative work-up are improved because all 3D parameters of the deformation are accessible. The need for 3D modeling for scoliosis has been known for a long time, but no tool allowing a vertical study with a low level of radiation was available. The EOS imagery system meets these criteria through an optimal analysis of deformations caused by scoliosis.


Asunto(s)
Imagenología Tridimensional , Escoliosis/diagnóstico por imagen , Adolescente , Niño , Humanos , Escoliosis/diagnóstico
4.
Cancer Res ; 52(12): 3396-401, 1992 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-1596899

RESUMEN

In some epithelial cells studied in vitro a membrane-bound folate receptor initiates the process for cell accumulation of 5-methyltetrahydrofolic acid. This receptor was found to be GP38, an overexpressed, glycosyl-phosphatidylinositol anchored glycoprotein, recognized by two monoclonal antibodies, designated MOv18 and MOv19. Using immunoblotting with MOv19, radioimmunoassay with MOv18 and 19, Northern blot analysis, and radioligand binding when possible, we describe the limited expression of the folate receptor in a large number of normal tissues from four autopsies. The immunoblot technique detected as little as 40 pg (approximately 1 fmol) of receptor protein. Choroid plexus consistently had the largest amount of folate receptor. Other tissues containing substantial amounts of receptor included lung, thyroid, and kidney. The liver, intestines, muscle, cerebellum, cerebrum, and spinal cord were immunologically nonreactive. Folate receptor gene expression determined by Northern blot analysis confirmed these observations. We also show that several malignant cell lines express significantly more receptor than normal epithelial cells or fibroblasts. Specifically, malignant cells bound greater than or equal to 20 pmol [3H]folate/10(6) cells, while normal epithelial cells and fibroblasts bound less than or equal to 1 pmol radioligand/10(6) cells. We also demonstrate that 4 of 6 brain tumors overexpress the folate receptor. These studies reveal the limited normal tissue distribution of the folate receptor, a cell surface protein which may be a useful immunological or pharmacological target for the development of selective cancer therapy.


Asunto(s)
Proteínas Portadoras/análisis , Receptores de Superficie Celular , Adulto , Neoplasias Encefálicas/química , Carcinoma de Células Renales/química , Femenino , Receptores de Folato Anclados a GPI , Humanos , Lactante , Neoplasias Renales/química , Masculino , Neoplasias/química , ARN Mensajero/análisis , ARN Neoplásico/análisis , Radioinmunoensayo , Valores de Referencia , Células Tumorales Cultivadas
5.
Cardiovasc Res ; 19(8): 483-94, 1985 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-4042115

RESUMEN

Amrinone, a positive inotropic-vasodilator agent, was administered to anaesthetised dogs in an attempt to reverse heart failure induced by drugs possessing negative inotropic properties. Propranolol, a beta-adrenergic blocker; verapamil, a calcium slow-channel blocker procainamide, a type 1 antiarrhythmic agent; or sodium pentobarbital, a barbituate; administered as a bolus injection and/or infusion, produced a sustained depression in canine cardiac function. Cardiac depression was characterised by a greater than 40% reduction in cardiac contractile force (CF) and maximum left ventricular pressure development (LV dp/dtmax), a 30 to 50% reduction in cardiac output (CO) and concomitant increases in mean central venous or mean right atrial blood pressures (CVP, RAP, respectively). Amrinone, when administered intravenously as a bolus injection (1 or 3 mg X kg-1) plus an infusion (0.03 or 0.1 mg X kg-1 X min-1) reversed the depression in cardiac function by increasing CF, CO and LV dp/dtmax and decreasing preload CVP or RAP in all four drug-induced failure models. Due to the vasodilator properties of amrinone, afterload, total peripheral resistance (TPR), was reduced in verapamil and procainamide failures as well as in propranolol failure, the only model where TPR increases. In another model of heart failure, in which ouabain-induced arrhythmias preceded procainamide toxicity, amrinone was also an effective cardiotonic agent. Ouabain's inotropic effect was studied in propranolol-induced heart failure. Although an increase in LV dp/dtmax and a decrease in CVP were noted, ouabain (40 micrograms X kg-1 iv) increased TPR and had little effect on the depression in CF and CO. Drug-induced models of heart failure were useful pharmacological tools for evaluating the cardiotonic agent's ability to overcome severe cardiac depression. In propranolol-, verapamil-, procainamide-, and pentobarbital-induced cardiac toxicity, amrinone could be of therapeutic value.


Asunto(s)
Aminopiridinas/uso terapéutico , Cardiotónicos/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Amrinona , Animales , Presión Sanguínea/efectos de los fármacos , Gasto Cardíaco/efectos de los fármacos , Presión Venosa Central/efectos de los fármacos , Perros , Femenino , Insuficiencia Cardíaca/inducido químicamente , Insuficiencia Cardíaca/fisiopatología , Masculino , Pentobarbital , Procainamida , Propranolol , Resistencia Vascular/efectos de los fármacos , Verapamilo
6.
J Med Chem ; 41(15): 2754-64, 1998 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-9667966

RESUMEN

Cryptolepine (1) is a rare example of a natural product whose synthesis was reported prior to its isolation from nature. In the previous paper we reported the discovery of cryptolepine's antihyperglycemic properties. As part of a medicinal chemistry program designed to optimize natural product lead structures originating from our ethnobotanical and ethnomedical field research, a series of substituted and heterosubstituted cryptolepine analogues was synthesized. Antihyperglycemic activity was measured in vitro and in an NIDDM mouse model to generate the first structure-bioactivity study about the cryptolepine nucleus.


Asunto(s)
Alcaloides/farmacología , Hipoglucemiantes/farmacología , Indoles , Plantas Medicinales/química , Quinolinas , Células 3T3 , Tejido Adiposo/citología , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/metabolismo , Alcaloides/síntesis química , Alcaloides/química , Animales , Transporte Biológico/efectos de los fármacos , Glucemia/metabolismo , Diabetes Mellitus Experimental/sangre , Glucosa/metabolismo , Hipoglucemiantes/síntesis química , Hipoglucemiantes/química , Alcaloides Indólicos , Ratones , Ratones Obesos , Relación Estructura-Actividad
7.
J Med Chem ; 41(6): 894-901, 1998 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-9526563

RESUMEN

Using an ethnobotanical approach in combination with in vivo-guided fractionation as a means for lead discovery, cryptolepine was isolated as an antihyperglycemic component of Cryptolepis sanguinolenta. Two syntheses of cryptolepine, including an unambiguous synthesis, are reported. The hydroiodide, hydrochloride, and hydrotrifluoromethanesulfonate (hydrotriflate) salts of cryptolepine were synthesized, and a comparison of their spectral properties and their in vitro activities in a 3T3-L1 glucose transport assay is made. Cryptolepine and its salt forms lower blood glucose in rodent models of type II diabetes. While a number of bioactivities have been reported for cryptolepine, this is the first report that cryptolepine possesses antihyperglycemic properties.


Asunto(s)
Alcaloides/farmacología , Hipoglucemiantes/farmacología , Indoles , Quinolinas , Células 3T3 , Tejido Adiposo/citología , Tejido Adiposo/efectos de los fármacos , Tejido Adiposo/metabolismo , Alcaloides/síntesis química , Alcaloides/química , Alcaloides/aislamiento & purificación , Animales , Glucemia/metabolismo , Peso Corporal/efectos de los fármacos , Diabetes Mellitus Experimental/metabolismo , Ingestión de Alimentos/efectos de los fármacos , Fructosa/administración & dosificación , Glucosa/metabolismo , Hipoglucemiantes/síntesis química , Hipoglucemiantes/química , Hipoglucemiantes/aislamiento & purificación , Técnicas In Vitro , Alcaloides Indólicos , Masculino , Ratones , Ratones Obesos , Extractos Vegetales/química , Extractos Vegetales/farmacología , Ratas , Ratas Sprague-Dawley
8.
Environ Health Perspect ; 106(12): 841-8, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9831545

RESUMEN

Water samples from several ponds in Minnesota were evaluated for their capacity to induce malformations in embryos of Xenopus laevis. The FETAX assay was used to assess the occurrence of malformations following a 96-hr period of exposure to water samples. These studies were conducted following reports of high incidences of malformation in natural populations of frogs in Minnesota wetlands. The purpose of these studies was to determine if a biologically active agent(s) was present in the waters and could be detected using the FETAX assay. Water samples from ponds with high incidences of frog malformations (affected sites), along with water samples from ponds with unaffected frog populations (reference sites), were studied. Initial experiments clearly showed that water from affected sites induced mortality and malformation in Xenopus embryos, while water from reference sites had little or no effect. Induction of malformation was dose dependent and highly reproducible, both with stored samples and with samples taken at different times throughout the summer. The biological activity of the samples was reduced or eliminated when samples were passed through activated carbon. Limited evidence from these samples indicates that the causal factor(s) is not an infectious organism nor are ion concentrations or metals responsible for the effects observed. Results do indicate that the water matrix has a significant effect on the severity of toxicity. Based on the FETAX results and the occurrence of frog malformations observed in the field, these studies suggest that water in the affected sites contains one or more unknown agents that induce developmental abnormalities in Xenopus. These same factors may contribute to the increased incidence of malformation in native species.


Asunto(s)
Anuros/anomalías , Ectromelia/veterinaria , Miembro Posterior/anomalías , Teratógenos/farmacología , Contaminantes Químicos del Agua/toxicidad , Animales , Ectromelia/inducido químicamente , Ectromelia/epidemiología , Monitoreo del Ambiente , Monitoreo Epidemiológico , Pruebas de Toxicidad/normas , Xenopus laevis/anomalías
9.
Environ Health Perspect ; 108(1): 83-90, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10620528

RESUMEN

The recent increase in the incidence of deformities among natural frog populations has raised concern about the state of the environment and the possible impact of unidentified causative agents on the health of wildlife and human populations. An open workshop on Strategies for Assessing the Implications of Malformed Frogs for Environmental Health was convened on 4-5 December 1997 at the National Institute of Environmental Health Sciences in Research Triangle Park, North Carolina. The purpose of the workshop was to share information among a multidisciplinary group with scientific interest and responsibility for human and environmental health at the federal and state level. Discussions highlighted possible causes and recent findings directly related to frog deformities and provided insight into problems and strategies applicable to continuing investigation in several areas. Possible causes of the deformities were evaluated in terms of diagnostics performed on field amphibians, biologic mechanisms that can lead to the types of malformations observed, and parallel laboratory and field studies. Hydrogeochemistry must be more integrated into environmental toxicology because of the pivotal role of the aquatic environment and the importance of fates and transport relative to any potential exposure. There is no indication of whether there may be a human health factor associated with the deformities. However, the possibility that causal agents may be waterborne indicates a need to identify the relevant factors and establish the relationship between environmental and human health in terms of hazard assessment.


Asunto(s)
Anomalías Congénitas/veterinaria , Ranidae/embriología , Contaminantes Químicos del Agua/efectos adversos , Xenobióticos/efectos adversos , Animales , Monitoreo del Ambiente , Humanos , Salud Pública , Ranidae/anatomía & histología , Medición de Riesgo
10.
Obstet Gynecol ; 72(3 Pt 1): 307-12, 1988 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3043286

RESUMEN

Vesicovaginal fistulas remain common and serious problems for women in West Africa. Thirty-six surgical repairs done during visiting professorships by American gynecologists between the years 1978-1987 are documented. The overall success rate was 70%. The management of large (greater than 4 cm) obstetric fistulas was especially difficult until the Latzko technique was abandoned for the technique of wide mobilization of vaginal flaps over the fistula site. This technique reduced the failure rate from 75% through 1986 to approximately 25% in 1987. Ongoing controversies and basic principles of surgical techniques in fistula repair are reviewed.


Asunto(s)
Fístula Vesicovaginal/cirugía , África Occidental , Drenaje , Estudios de Evaluación como Asunto , Femenino , Estudios de Seguimiento , Humanos , Métodos , Postura , Reoperación , Estudios Retrospectivos , Técnicas de Sutura , Fístula Vesicovaginal/epidemiología
11.
Obstet Gynecol ; 84(1): 148-52, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8008312

RESUMEN

We performed a modified bulbocavernosus full-thickness pedicle graft procedure on four patients with large obstetric fistulas in Ghana, West Africa. The bulbocavernosus fat pad was harvested in the usual manner, and the full-thickness skin patch was taken from the medial thigh. All grafts showed 100% take by the tenth postoperative day. Adequate vaginal depth and caliber were obtained in all patients. Sexual function resumed in all patients except one, who suffered a recurrent vesicovaginal fistula. This method of vaginoplasty may be useful in patients who have massive vaginal-wall destruction of either gynecologic or obstetric origin.


Asunto(s)
Fístula Rectovaginal/cirugía , Colgajos Quirúrgicos/métodos , Enfermedades Uretrales/cirugía , Fístula Urinaria/cirugía , Fístula Vaginal/cirugía , Fístula Vesicovaginal/cirugía , Adulto , Femenino , Supervivencia de Injerto , Humanos , Proyectos Piloto , Fístula Rectovaginal/complicaciones , Reoperación/métodos , Conducta Sexual , Insuficiencia del Tratamiento , Enfermedades Uretrales/complicaciones , Fístula Urinaria/complicaciones , Fístula Vaginal/complicaciones , Fístula Vesicovaginal/complicaciones , Vulva/irrigación sanguínea , Cicatrización de Heridas
12.
J Child Neurol ; 12(3): 157-64, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9130087

RESUMEN

Congenital central nervous system (CNS) tumors are a rare and diverse group of tumors with variable biological behavior depending on location and histology. This review summarizes the published literature and describes the definition, epidemiology, diagnosis and evaluation, and treatment of congenital central nervous system tumors.


Asunto(s)
Neoplasias del Sistema Nervioso Central/congénito , Neoplasias Encefálicas/congénito , Neoplasias del Sistema Nervioso Central/epidemiología , Neoplasias del Sistema Nervioso Central/patología , Humanos , Lactante , Recién Nacido , Neoplasias Meníngeas/congénito , Neoplasias de la Médula Espinal/congénito
13.
Food Chem Toxicol ; 36(7): 591-600, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9687966

RESUMEN

The developmental toxicities of caffeine and 13 metabolites, including theophylline, and paraxanthine and a synthetic methylxanthine analogue 3-isobutyl-methylxanthine (IBMX) were evaluated using the Frog Embryo Teratogenesis Assay Xenopus (FETAX). Young X. laevis embryos were exposed to these compounds in each of two separate concentration-response experiments with and without an exogenous metabolic activation system (MAS). Results obtained from these studies indicated that relative teratogenic potencies of caffeine and each of its di- and monomethylxanthine metabolites were similar. Representatives of both the substituted uric and uracil metabolites were less developmentally toxic on an equimolar basis than the methylxanthines, suggesting that they may have represented detoxification metabolites. IBMX, a phosphodiesterase inhibitor also known to be an adenosine receptor antagonist, was the most potent developmental toxicant of the materials evaluated. In conclusion, none of the caffeine metabolites tested was found to be significantly more potent than caffeine itself in the FETAX assay.


Asunto(s)
Cafeína/toxicidad , Estimulantes del Sistema Nervioso Central/toxicidad , Embrión no Mamífero/efectos de los fármacos , Xenopus/embriología , Anomalías Inducidas por Medicamentos/etiología , Animales , Biotransformación , Embrión no Mamífero/anomalías , Femenino , Masculino , Microsomas Hepáticos/metabolismo , Ratas , Ratas Sprague-Dawley
14.
Biol Trace Elem Res ; 66(1-3): 237-59, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-10050923

RESUMEN

Frog embryo teratogenesis assay--Xenopus (FETAX) was utilized as a model system to evaluate the effects on embryo-larval development at various low boron (B) exposure levels in the culture media. Concentrations tested ranged from < 1 to 5000 microg B/L. A statistically significant (P < 0.05) increase in malformations was observed at < or = 3 microg B/L, but not at the greater concentrations. Abnormal development of the gut, craniofacial region and eye, visceral edema, and kinking of the tail musculature (abnormal myotome development) and notochord were observed. In subsequent studies, adult frogs were maintained for 28 d on two diets: (1) low B (LB, 62 microg B/kg) or (2) boric acid supplemented (BA, 1851 microg B/kg); the frogs were subsequently mated, and their offspring were cultured in media containing various levels of B. Results of the 28-d depletion studies indicated that frogs maintained under LB conditions produced a greater proportion of (1) necrotic eggs and (2) fertilized embryos, which abnormally gastrulated at a greater rate and were substantially less viable than embryos from frogs fed the BA diet. Malformations similar to those seen in the initial study were observed in embryos from the B-depleted adults maintained in an LB environment; 28 d on the LB diet enhanced the incidence of malformations associated with the LB culture media. These abnormalities were not observed in embryos cultured in > or = 4 microg B/L from adults cultured on the BA diet. These studies showed that insufficient B reproducibly interfered with normal Xenopus laevis development during organogenesis, substantially impaired normal reproductive function in adult frogs, and thus represent the first studies demonstrating the nutritional essentiality of B in an amphibian species.


Asunto(s)
Boro/deficiencia , Anomalías Congénitas/etiología , Reproducción/efectos de los fármacos , Xenopus laevis/fisiología , Animales , Boro/administración & dosificación , Cobre/farmacología , Dieta , Suplementos Dietéticos , Embrión no Mamífero/efectos de los fármacos , Femenino , Deformidades Congénitas de las Extremidades/etiología , Masculino , Xenopus laevis/embriología , Zinc/farmacología
15.
Biol Trace Elem Res ; 77(2): 159-72, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11101048

RESUMEN

The effect of copper (Cu) deficiency on the reproduction and development in Xenopus laevis was evaluated, culminating in the development of a defined concentration-response relationship. Separate groups of four adult frog pairs were fed one of three diets for 28 d: (1) low-copper (-Cu); (2) copper supplemented (+Cu); and (3) ASTM standard beef liver and lung (BLL). Embryos collected from frogs administered the -Cu diet had markedly decreased egg masses and viability rates and an increased rate of necrosis when compared to the other dietary treatments. Malformations in -Cu larvae included maldevelopment of the heart, eye, craniofacial region, brain, and notochord. Larvae from adults administered the -Cu diet showed delayed abnormal hindlimb development, characterized as selective reductive deficiencies distal to the femur, with poor cartilaginous development. A U-shaped dose-response curve characteristic of nutritional essentiality was developed for Cu. Overall, these studies indicated that embryos produced from frogs administered a -Cu diet are substantially less viable than embryos from frogs administered a +Cu or copper-adequate (BLL) diet.


Asunto(s)
Anomalías Congénitas/etiología , Cobre/deficiencia , Xenopus laevis/embriología , Animales , Cobre/análisis , Femenino
16.
Biol Trace Elem Res ; 77(2): 173-87, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11101049

RESUMEN

Sets of adult male and female Xenopus laevis were administered a boron-deficient (-B) diet under low-boron culture conditions, a boron-supplemented (+B) diet under ambient boron culture conditions, a copper-deficient (-Cu) diet under low-copper culture conditions, or a copper-supplemented (+Cu) diet under ambient copper culture conditions, for 120 d. Adults from each group were' subsequently bred, and the progeny were cultured and bred. Results from these studies indicated that although pronounced effects on adult reproduction and early embryo-larval development were noted in the -B F1 generation, no effects on limb development were observed. No significant effects on reproduction, early embryogenesis, or limb development were noted in the +B group, irrespective of generation. Highly specific forelimb and hindlimb defects, including axial flexures resulting in crossed limbs and reduction deficits, were observed in -B F2 larvae, but not in the +B F2 larvae. As was noted in the boron-deficiency studies, significant effects on reproduction and early embryo development were observed in the -Cu F1 generation, but not in the +Cu F, generation. Unlike the effects associated with boron deficiency, maldevelopment of the hindlimbs (32 responders, n = 40) was found in the F1 generation.


Asunto(s)
Boro/deficiencia , Cobre/deficiencia , Deformidades Congénitas de las Extremidades/etiología , Xenopus laevis/embriología , Animales , Femenino , Masculino
17.
Rev Neurol (Paris) ; 144(5): 365-7, 1988.
Artículo en Francés | MEDLINE | ID: mdl-3420353

RESUMEN

Lesions of cortex and white matter are present in Wilson's disease in approximately 10 p. cent of cases. Before Magnetic Resonance Imaging (MRI) only post-mortem examination evidenced them. We report the case of a 15 year-old girl in whom Wilson's disease was diagnosed after partial motor epileptic seizures. She later presented with progressive extrapyramidal and pyramidal signs, severe cognitive weakening and disorder of behaviour. MRI clearly showed cortical and subcortical lesions by an enhanced signal (T2 values). It showed as well the classical picture of lesion in the lenticular nuclei. With T1 values it showed an extensive cortical atrophy and a widening of the ventricules.


Asunto(s)
Encéfalo/patología , Degeneración Hepatolenticular/patología , Imagen por Resonancia Magnética , Adolescente , Corteza Cerebral/patología , Electroencefalografía , Femenino , Humanos
18.
Rev Neurol (Paris) ; 144(3): 173-80, 1988.
Artículo en Francés | MEDLINE | ID: mdl-3368692

RESUMEN

The distinction between radiation and tumor brachial plexopathy may be difficult. The electrophysiological recording of myokymic discharges, frequently present in the former but rare in the latter type of plexopathy, can be helpful for the diagnosis. However, the pathophysiology and the site of origin of these discharges remain unclear. We describe a patient presenting with radiation brachial plexopathy, clinical myokymia, cramps and pain. In this patient, the myokymia--due to abundant myokymic discharges--and the cramps, were related to the existence of persistent conduction block of several years duration. Several findings suggest that the myokymic discharges were generated on blocked axons: voluntary activity did not influence their occurrence nor modify their course; the motor unit potentials involved in the discharges were not evoked by stimulation proximal to the site of the conduction block, whereas the stimulation distal to this site could evoke, modify the rhythm, or interrupt the course of the discharges; the latency of these evoked responses indicated that the site of reflection was proximal on the axon, and likely coincided with that of the conduction block. Recent observations (Roth and Magistris, 1987b) indicated that myokymia, produced by numerous single or grouped fasciculations generated on axon terminals, may be related to persistent conduction blocks of various etiologies. The present case demonstrates that myokymia provoked by myokymic discharges may as well be related to persistent conduction block. The reason why these blocks are accompanied by fasciculations in some situations and by myokymic discharges in others remains an unsolved question. The cramps observed in this patient were also of interest as they occurred in the muscle territory of blocked axons and were provoked by passive muscle shortening. Their origin, distal to the conduction block, is unknown. Finally, a neurolysis did not prevent the progressive transformation of conduction block into axonotmesis.


Asunto(s)
Plexo Braquial/efectos de la radiación , Fasciculación/etiología , Calambre Muscular/etiología , Conducción Nerviosa/efectos de la radiación , Neoplasias de la Mama/radioterapia , Electrofisiología , Fasciculación/fisiopatología , Femenino , Humanos , Persona de Mediana Edad
19.
J Phys Condens Matter ; 24(3): 036002, 2012 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-22156039

RESUMEN

We report inelastic neutron scattering measurements and random phase approximation calculations of the dispersive crystal field excitations of UPd(3). The measured spectra at lower energies agree with those calculated using quadrupolar interaction parameters deduced from bulk and x-ray scattering measurements. The more intense excitations arising from the hexagonal sites were used to obtain exchange parameters which proved to be anisotropic.

20.
Phys Rev Lett ; 62(4): 470-473, 1989 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-10040241
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