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2.
Ann Readapt Med Phys ; 48(2): 93-100, 2005 Mar.
Artículo en Francés | MEDLINE | ID: mdl-15748774

RESUMEN

OBJECTIVE: To define retraining after injury in a high-level cyclist by taking into account the consequences of detraining. METHOD: From three clinical cases and from the analysis of the consequences of detraining, three principles of retraining were determined. RESULTS: 1. The high-level cyclist is not protected and loses cycling capacity after four weeks of inactivity. The delay in recovery is longer the higher the adaptations. 2. Recovery of cycling capacity is based on bicycle exercises that are greater in intensity than quantity, taking into account delays in injury consolidation. 3. Retraining requires appreciating the individual physiological level by evaluating force and endurance before envisaging the resumption of training and competition. CONCLUSION: The injury of a high-level cyclist is at the origin of detraining, which has been evaluated so that sports rehabilitation may enable the cyclist to find a previous state without relapse, complication or overtraining.


Asunto(s)
Traumatismos en Atletas/rehabilitación , Ciclismo/lesiones , Adulto , Humanos , Masculino
3.
Int J Sports Med ; 25(8): 575-81, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15531999

RESUMEN

The aim of the study was to evaluate the presence of cerebral lesions in asymptomatic scuba divers and explain the causes of them: potential risk factors associating cardiovascular risk factors, low aerobic capacity, or characteristics of diving (maximum depth, ascent rate). Experienced scuba divers, over 40 years of age, without any decompression sickness (DCS) history were included. We studied 30 scuba divers (instructors) without any clinical symptoms. For all of them, we carried out a clinical examination with fatty body mass determination and we questioned them about their diving habits. A brain Magnetic Resonance imaging (MRI), an assessment of maximal oxygen uptake, glycemia, triglyceridemia, and cholesterolemia were systematically carried out. Cerebral spots of high intensity were found at 33 % in the scuba diving group and 30 % in the control group. In the diving group, abnormalities were related to unsafe scuba-diving or metabolic abnormalities. In our study, we did not find a significant relationship between the lesions of the central nervous system, and the age, depth of the dives, number of dives, and ergometric performances (maximal oxygen uptake, V.O (2max), serum level of blood lactate). Nevertheless, we found a significant relationship between the lesions of the central nervous system and ascent rate faster than 10 meters per minute (r = 0.57; p = 0.003) or presence of high level of cholesterolemia (r = 0.6; p = 0.001). We found concordant results using the Cochran's Test: meaningful link between the number of brain lesions and the speed of decompression (Uexp = 14 < Utable = 43; alpha = 0.05, p < 0.01). We concluded that hyperintensities can be explained by preformed nitrogen gas microbubbles and particularly in presence of cholesterol, when the ascent rate is up to 10 meters per minute. So, it was remarkable to note that asymptomatic patients practicing scuba diving either professionally or recreationally, presented lesions of the central nervous system. This survey permitted us to highlight in a population of professional divers, neurological and also cardiovascular abnormalities (ventricular arrhythmias); although none of them present any symptoms today. It seems therefore important to us to propose in the future, for a better prevention of neurological injuries, a systematic follow-up by maximal oxygen consumption measure, brain MRI, and cholesterolemia. In the same way, our results suggest a modification of the diving tables with a maximal decompression rate at 9 m . mn (-1).


Asunto(s)
Encéfalo/patología , Buceo , Hipercolesterolemia/sangre , Imagen por Resonancia Magnética , Consumo de Oxígeno/fisiología , Estudios de Casos y Controles , Descompresión/efectos adversos , Descompresión/métodos , Femenino , Humanos , Hipertensión/diagnóstico , Masculino , Persona de Mediana Edad , Análisis Multivariante , Nitrógeno/sangre , Taquicardia Ventricular/diagnóstico
4.
Ann Dermatol Venereol ; 129(8-9): 1042-5, 2002.
Artículo en Francés | MEDLINE | ID: mdl-12442104

RESUMEN

BACKGROUND: Erythema gyratum repens is a rare cutaneous marker for internal malignancy and the association with other paraneoplastic syndromes is not unusual. CASE REPORT: We report the case of a 54 year-old man with a three-month history of erythroderma which evolved into erythema gyratum repens; a bronchial carcinoma was discovered. Erythema gyratum repens was associated with acquired ichthyosis, hyperkeratosis of the ears and eosinophilia. Improvement of the paraneoplastic dermatosis was achieved by treatment of the underlying carcinoma with chemotherapy, surgery and radiation. However, the lesions relapsed when metastases appeared. Another regimen of chemotherapy improved the carcinoma and the dermatosis. DISCUSSION: The parallel course of the carcinoma and the cutaneous eruption strongly supports the diagnosis of a cutaneous paraneoplastic syndrome. Three months prior to erythema gyratum repens, the patient developed a scaling erythroderma. This unusual early manifestation is misleading. Our case highlights the possible association of different paraneoplastic syndromes: initially scaling erythroderma, followed by erythema gyratum repens associated with acquired ichthyosis, hyperkeratosis of the ears and eosinophilia.


Asunto(s)
Adenocarcinoma/complicaciones , Desoxicitidina/análogos & derivados , Dermatitis Exfoliativa/etiología , Eritema/etiología , Neoplasias Pulmonares/complicaciones , Síndromes Paraneoplásicos , Adenocarcinoma/diagnóstico , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/cirugía , Antimetabolitos Antineoplásicos/administración & dosificación , Antineoplásicos/administración & dosificación , Antineoplásicos Fitogénicos/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carboplatino/administración & dosificación , Cisplatino/administración & dosificación , Desoxicitidina/administración & dosificación , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/cirugía , Escisión del Ganglio Linfático , Masculino , Persona de Mediana Edad , Paclitaxel/administración & dosificación , Neumonectomía , Radiografía Torácica , Factores de Tiempo , Tomografía Computarizada por Rayos X , Gemcitabina
5.
Arch Pediatr ; 9(5): 478-88, 2002 May.
Artículo en Francés | MEDLINE | ID: mdl-12053541

RESUMEN

UNLABELLED: Pulmonary function testing is not usually done in the preschool child, despite the recent data showing early deterioration in airway function in asthma. METHODS: We evaluated feasibility and clinical interest of flow-volume loop by forced expiratory maneuver and measure of airway resistance by interrupter technique (interrupter resistance), before and after inhalation of salbutamol, in 75 children aged three to five years seen in the ambulatory setting for asthma. RESULTS: Feasibility rate (92%) and reproducibility rate (91%) of those techniques were good, so that 84% of the cases could be exploited (63 children of 75). We found few significant associations between clinical parameters and flow-volume loop. We found a significant association between elevated interrupter resistance at basis and night-symptoms (P = 0.03), between diminished interrupter resistance after salbutamol and exercise-symptoms (P = 0.03), symptoms in the ambulatory setting (P = 0.02) and absence of inhaled corticosteroid treatment (P = 0.046). Pulmonary function testing resulted in treatment modification in 14% of cases. CONCLUSION: Our study shows that flow-volume loop and measure of airway resistance by interrupter technique can be done with a good reproducibility in the preschool child. Interrupter resistance appears to be better correlated than flow-volume loop with usually evaluated clinical parameters.


Asunto(s)
Asma/fisiopatología , Pruebas de Función Respiratoria/métodos , Preescolar , Femenino , Flujo Espiratorio Forzado/fisiología , Volumen Espiratorio Forzado/fisiología , Humanos , Masculino , Flujo Espiratorio Máximo/fisiología , Reproducibilidad de los Resultados , Espirometría
6.
Dev Biol ; 233(1): 161-73, 2001 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-11319865

RESUMEN

During mouse blastocyst formation, a layer of outer cells differentiates in less than 48 h into a functional epithelium (the trophectoderm). Ezrin, an actin-binding structural component of microvilli in epithelial cells, is also involved in signal transduction and ionic pump control. In the mouse embryo, ezrin becomes restricted to the apical cortex of all blastomeres at compaction and of outer cells at later stages. Here we investigated the function of ezrin in living embryos during epithelial differentiation using mutant forms of ezrin tagged with green fluorescent protein (GFP). GFP-tagged wild-type ezrin (Ez/GFPc) behaved like endogenous ezrin and did not interfere with development. Deletion of the last 53 amino acids (Delta53/GFP) changed the localization of ezrin: after compaction, Delta53/GFP remained associated with the apical and basolateral cortex in all blastomeres, and its expression slightly disturbed the cavitation process. Finally, full-length ezrin with GFP inserted at position 234 (Ez/GFPi) was localized all around the cortex throughout development, although it was concentrated at the apical pole after compaction. In embryos expressing Ez/GFPi, the duration of the 16-cell stage was reduced, while the onset of cavitation was delayed. Moreover, cavitation was abnormal, and the blastocoele was small and retracted almost completely several times as if there were major leakages of blastocoelic fluid. Our results suggest that, in addition to its role in microvilli organization, ezrin is involved in the formation of a functional epithelium through a still unknown mechanism.


Asunto(s)
Blastocisto/ultraestructura , Fosfoproteínas/aislamiento & purificación , Animales , Proteínas del Citoesqueleto , Embriología/métodos , Proteínas Fluorescentes Verdes , Proteínas Luminiscentes , Ratones , Microscopía por Video , Morfogénesis , Mutación , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Proteínas Recombinantes de Fusión/aislamiento & purificación , Proteínas Recombinantes de Fusión/metabolismo , Eliminación de Secuencia
7.
Ann Dermatol Venereol ; 127(2): 160-5, 2000 Feb.
Artículo en Francés | MEDLINE | ID: mdl-10739973

RESUMEN

OBJECTIVE: The incidence of cutaneous melanoma has rapidly increased in the white population over the last decades. It has been estimated that the incidence doubles world-wide every 10 years. Different risk factors have been identified, including immunosuppression. The aim of our study-was to determine the relative risk of developing melanoma in the organ transplant population and the clinical and histological features of their melanomas. PATIENTS AND METHODS: This retrospective study was conducted with the collaboration of 9 University Hospital Centers: Besançon, Brest, Caen, Dijon, Lille, Lyon, Nantes, Paris (Pitié-Salpétrière) and Rennes. A questionnaire was sent to the different departments of dermatology of these hospitals to obtain information on patients who had presented a melanoma after a transplantation between 1971 and 1997. During this period, there were 12,477 organ transplant recipients in the transplantation units of these 9 hospitals. Average follow-up for these patients was about 5 years and the average duration of immunosuppressive therapy was about 4.5 years. RESULTS: Among 12,477 organ transplant recipients, we found 17 cases of melanoma but no data could be obtain on one case: 14 occurred in renal transplant recipients and 3 in cardiac transplant recipients. Clinical and histological data were only available in 16 patients. The average time between transplantation and diagnosis of melanoma was 63 months, but it was 5 times shorter for 2 patients who had a past history of melanoma before transplantation. Two patients had a mucosal melanoma; for the cutaneous melanomas, 2 appeared on Dubreuilh melanosis, 2 were in situ melanomas, 7 were superficial spreading melanomas and 3 were nodular melanomas. The histological review of 11 cutaneous melanomas revealed a precursor nevus in 6 cases and a weak or no stroma reaction in 7/7 cases. Complete excision of the melanoma was performed in all patients except one with anorectal melanoma. Four patients died of visceral metastasis within a mean 15 months. The other 12 patients are still alive with a mean 3 year course since tumor treatment. We tried to determine the relative risk of developing melanoma in the renal transplant population (14 cases). The number of expected cases of melanoma was 5.54, giving a relative risk of 2.5. DISCUSSION: Only 4 studies have shown an increase in the incidence of melanoma in the renal transplant population: approximately 2 to 5-fold. In our study, the 2.5-fold increase in melanoma was estimated with an average 5 year follow-up and an average 5 year immunosuppressive therapy. This is probably an underestimation of risk because we were unable to make an exhaustive collection of cases of melanomas even though transplant recipients undergo more physical examinations than a reference population. The mean latency period from transplantation to melanoma diagnosis was 63 months, as in other studies. Histological examination showed that a precursor nevus is frequent with weak host cellular response to the tumor. The prognosis of these melanomas remains difficult to predict, but in our study, it would not appear to be as poor as expected. Discontinuation of immunosuppressive therapy would not appear to be necessary except in the presence of metastasis. Finally, our study demonstrates the importance of good patient follow-up, even after graft rejection due to the persistent risk of melanoma.


Asunto(s)
Melanoma/etiología , Trasplante de Órganos , Complicaciones Posoperatorias/etiología , Neoplasias Cutáneas/etiología , Adulto , Causas de Muerte , Femenino , Estudios de Seguimiento , Humanos , Terapia de Inmunosupresión , Masculino , Melanoma/mortalidad , Persona de Mediana Edad , Complicaciones Posoperatorias/mortalidad , Estudios Retrospectivos , Factores de Riesgo , Neoplasias Cutáneas/mortalidad , Tasa de Supervivencia
8.
Development ; 125(24): 4989-97, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9811583

RESUMEN

To study the mechanisms involved in the progression of meiotic maturation in the mouse, we used oocytes from two strains of mice, CBA/Kw and KE, which differ greatly in the rate at which they undergo meiotic maturation. CBA/Kw oocytes extrude the first polar body about 7 hours after breakdown of the germinal vesicle (GVBD), whilst the oocytes from KE mice take approximately 3-4 hours longer. In both strains, the kinetics of spindle formation are comparable. While the kinetics of MAP kinase activity are very similar in both strains (although slightly faster in CBA/Kw), the rise of cdc2 kinase activity is very rapid in CBA/Kw oocytes and slow and diphasic in KE oocytes. When protein synthesis is inhibited, the activity of the cdc2 kinase starts to rise but arrests shortly after GVBD with a slightly higher level in CBA/Kw oocytes, which may correspond to the presence of a larger pool of cyclin B1 in prophase CBA/Kw oocytes. After GVBD, the rate of cyclin B1 synthesis is higher in CBA/Kw than in KE oocytes, whilst the overall level of protein synthesis and the amount of messenger RNA coding for cyclin B1 are identical in oocytes from both strains. The injection of cyclin B1 messenger RNA in KE oocytes increased the H1 kinase activity and sped up first polar body extrusion. Finally, analysis of the rate of maturation in hybrids obtained after fusion of nuclear and cytoplasmic fragments of oocytes from both strains suggests that both the germinal vesicle and the cytoplasm contain factor(s) influencing the length of the first meiotic M phase. These results demonstrate that the rate of cyclin B1 synthesis controls the length of the first meiotic M phase and that a nuclear factor able to speed up cyclin B synthesis is present in CBA/Kw oocytes.


Asunto(s)
Quinasas CDC2-CDC28 , Ciclina B/genética , Quinasas Ciclina-Dependientes/metabolismo , Meiosis/fisiología , Oocitos/fisiología , Proteínas Serina-Treonina Quinasas/metabolismo , Animales , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Cromosomas/metabolismo , Ciclina B/metabolismo , Ciclina B1 , Quinasa 2 Dependiente de la Ciclina , Femenino , Técnica del Anticuerpo Fluorescente , Glucógeno Sintasa Quinasa 3 , Células Híbridas/metabolismo , Cinética , Ratones , Ratones Endogámicos , Microinyecciones , Microtúbulos/metabolismo , Mitosis/genética , Fosforilación , Proteínas Quinasas/metabolismo , ARN Mensajero/genética
9.
Ann Dermatol Venereol ; 125(6-7): 399-403, 1998 Jul.
Artículo en Francés | MEDLINE | ID: mdl-9747294

RESUMEN

INTRODUCTION: Cutaneous lichen planus in children is a rare entity. To study its specific clinical and therapeutic features, we report on 8 cases seen in 5 years in a pediatric dermatology clinic. In parallel, this study addresses the role of HBV immunization campaigns in childhood lichen planus. OBSERVATIONS: Six boys and two girls with a diffuse form of lichen planus were studied. The mean age was 11 years. Four children were of skin types V and VI. Lesions followed Blaschko's lines in two children. One case was associated with atopic dermatitis. In half the cases--the most recent--the eruption was noted after HBV immunization. Biopsy specimens from seven children were reviewed and confirmed the diagnostic of lichen planus. Oral retinoids or corticosteroids were used successfully in six cases. DISCUSSION: Half of our cases confirmed the atypical features of lichen planus in childhood. This study confirms the predominance of lichen planus in children with pigmented skin suggesting a genetic predisposition. The eruption following Blaschko's lines suggests that a clonal keratinocytic population is the target of lichenoid inflammation. HBV immunization could be a stimulus triggering a cytotoxic lymphocyte-mediated reaction. The proportion of affected children was low in comparison with all children immunized. So lichen planus arises probably in predisposed children. This justifies surveillance in the pediatric and dermatologic medical communities.


Asunto(s)
Vacunas contra Hepatitis B/efectos adversos , Hepatitis B/prevención & control , Liquen Plano/inducido químicamente , Adolescente , Niño , Preescolar , Susceptibilidad a Enfermedades , Femenino , Humanos , Lactante , Masculino
11.
Photodermatol Photoimmunol Photomed ; 13(3): 93-7, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9372525

RESUMEN

The aim of this study was to evaluate the possibility of cross-reactivity between ketoprofen, fenofibrate and benzophenones because of their structural similarities. Seven patients presenting photodermatitis from ketoprofen underwent patch and photopatch tests. Ketoprofen, fenofibrate, benzophenone 3, benzophenone 10, benzophenone 4, personal medications and topical creams were tested. All patients had positive patch or photopatch tests to ketoprofen and fenofibrate, four patients had positive UVA photopatch tests to benzophenone 3, and two to benzophenone 10. Patients presenting photosensitization to ketoprofen may also have cross-reactivity to fenofibrate and some benzophenones.


Asunto(s)
Antiinflamatorios no Esteroideos/efectos adversos , Benzofenonas/efectos adversos , Fenofibrato/efectos adversos , Hipolipemiantes/efectos adversos , Cetoprofeno/efectos adversos , Trastornos por Fotosensibilidad/inducido químicamente , Fármacos Fotosensibilizantes/efectos adversos , Protectores Solares/efectos adversos , Adulto , Antiinflamatorios no Esteroideos/química , Benzofenonas/química , Cosméticos/efectos adversos , Reacciones Cruzadas , Interacciones Farmacológicas , Femenino , Fenofibrato/química , Humanos , Hipolipemiantes/química , Cetoprofeno/química , Masculino , Persona de Mediana Edad , Pruebas del Parche , Fármacos Fotosensibilizantes/química , Relación Estructura-Actividad , Protectores Solares/química , Rayos Ultravioleta
12.
Photodermatol Photoimmunol Photomed ; 13(3): 98-102, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9372526

RESUMEN

Hydroa vacciniforme vesicles can be reproduced experimentally with repetitive UVA irradiations, but this photo-reproduction is not constant. The aim of this study was to search for the factors that influence photo-reproduction. To reproduce hydroa vacciniforme lesions six patients underwent repetitive UVA and polychromatic irradiations on the back. In four patients out of six, UVA irradiation with high doses induced papulo-vesicular lesions. Photo-induced lesions were very close to those induced by sunlight. Photo-reproduction failed when phototesting was done after or shortly before remission. Therefore, the absence of photo-reproduction appears to be a good prognostic factor.


Asunto(s)
Hidroa Vacciniforme/etiología , Rayos Ultravioleta/efectos adversos , Adolescente , Adulto , Niño , Cicatriz/patología , Eritema/etiología , Eritema/fisiopatología , Femenino , Humanos , Hidroa Vacciniforme/patología , Hidroa Vacciniforme/fisiopatología , Masculino , Necrosis , Pronóstico , Prurito/etiología , Dosis de Radiación , Recurrencia , Remisión Espontánea , Piel/patología , Pruebas Cutáneas/métodos , Luz Solar/efectos adversos
14.
Contact Dermatitis ; 36(3): 147-9, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9145264

RESUMEN

Sensitivity to histamine H1-antagonists has mainly been observed with phenothiazine and ethylenediamine, and is very rare with hydroxyzine. We report 3 cases of sensitization to hydroxyzine, which was prescribed to treat urticaria and atopic dermatitis. A generalized maculopapular eruption appeared shortly after taking the drug. Patch tests with Atarax tablet were positive +3, and +2 or +3 with different dilutions of hydroxyzine. Patch tests with ethylenediamine, piperazine and other antihistamines were negative; therefore, there is no cross-allergy. We believe these rapid systemic reactions to hydroxyzine after the initial dose may have been due to prior systemic sensitivity to this drug, which cannot be used topically. Allergy to antihistamines must be considered when cutaneous lesions worsen on such therapy.


Asunto(s)
Erupciones por Medicamentos/etiología , Antagonistas de los Receptores Histamínicos H1/efectos adversos , Hidroxizina/efectos adversos , Adulto , Anciano , Dermatitis Atópica/tratamiento farmacológico , Femenino , Antagonistas de los Receptores Histamínicos H1/farmacología , Humanos , Hidroxizina/farmacología , Embarazo , Complicaciones del Embarazo/etiología , Urticaria/tratamiento farmacológico
15.
Ann Dermatol Venereol ; 124(8): 549-51, 1997.
Artículo en Francés | MEDLINE | ID: mdl-9740851

RESUMEN

BACKGROUND: Encephalocraniocutaneous lipomatosis (ECL) involving the scalp and cerebellum was observed without asymptomatic expression. CASE REPORT: A seven-month-old infant presented with two soft subcutaneous hairless tumors of the scalp without any associated clinical anomaly. Neuroradiology explorations (radiography, CT-scan and MRI) showed a lipoma in the cerebellum linked with a occipital cutaneous lipoma through a bone defect. At the age of 3 years, the child remains healthy. DISCUSSION: ECL is a rare neurocutaneous disorder that consists of skin lipomas associated with various cerebral anomalies. ECL may occur as a circumscribed form of the Proteus syndrome, since a few ECL patients have associated manifestations of proteus syndrome as well as localized hypertrophy. However, minor forms of ECL are possible and may be compatible with normal life.


Asunto(s)
Encefalopatías/etiología , Lipomatosis/complicaciones , Dermatosis del Cuero Cabelludo/etiología , Encefalopatías/diagnóstico , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Radiografía , Cráneo/anomalías , Cráneo/diagnóstico por imagen
16.
Br J Dermatol ; 135(6): 988-90, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8977725

RESUMEN

PUVA lentigines do not subside after discontinuation of photochemotherapy. Cryotherapy with liquid nitrogen was done on a small area in a patient who presented with numerous PUVA lentigines. Five years after this treatment, the PUVA lentigines had not returned. Cosmetically disturbing PUVA lentigines can be treated with cryotherapy.


Asunto(s)
Crioterapia , Lentigo/etiología , Lentigo/terapia , Terapia PUVA/efectos adversos , Femenino , Humanos , Lentigo/patología , Persona de Mediana Edad , Psoriasis/patología , Psoriasis/terapia , Piel/patología
18.
Dev Biol ; 177(2): 568-79, 1996 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-8806832

RESUMEN

During preimplantation development in the mouse, two phenotypically distinct cell populations appear at the 16-cell stage: nonpolarized inner cells that give rise to the inner cell mass and polarized outer cells that give rise mainly to the trophectoderm. The divergence of these two cell lineages is due to asymmetrical cell divisions during the transition from the 8- to the 16 cell stage which can occur following blastomere polarization. During compaction, at the 8-cell stage, cytoplasmic organelles accumulate in the apical domain, a surface pole of microvilli forms, and blastomeres flatten onto one another. During the division from the 8- to the 16-cell stage, the only asymmetrical structure maintained is the pole of microvilli. At the 16-cell stage, only blastomeres inheriting a large part of this apical structure can reestablish a polarized organization. The mechanisms involved in the formation and stabilization of the apical pole of microvilli are still unknown. Ezrin is an actin-associated protein that has been proposed to play a role in the formation of microvillous structures. This led us to study the expression of ezrin during early development of the mouse embryo. We observed that ezrin mRNA and protein are present in the mouse oocyte and throughout preimplantation embryo development, although the amount of protein present decreases continuously during early development, particularly after the 8-cell stage, at the time of compaction. Two isoforms of ezrin phosphorylated on tyrosine residues are present during all of preimplantation development while a third non-tyrosine-phosphorylated isoform appears at the 8-cell stage and its relative amount increases from the 8-cell stage to the blastocyst stage. Before compaction, ezrin is distributed around the cell cortex. However ezrin becomes restricted to the microvilli of the apical pole after compaction. At later stages, ezrin is found in the microvilli of the apical surface of outer cells. Finally, ezrin remains associated with the microvillous pole during the transition from the 8- to 16-cell stage and is found only in the outer cells after division. Thus, ezrin is the first cytocortical protein described that is totally segregated in outer cells at the 16-cell stage after an asymmetrical division.


Asunto(s)
Desarrollo Embrionario/fisiología , Ratones/embriología , Fosfoproteínas/biosíntesis , ARN Mensajero/análisis , Animales , Secuencia de Bases , Blastocisto/metabolismo , Proteínas del Citoesqueleto , Femenino , Fertilización In Vitro , Proteínas Fetales/química , Proteínas de la Membrana/química , Microvellosidades/química , Mitosis/fisiología , Datos de Secuencia Molecular , Oligonucleótidos Antisentido/farmacología , Fosfoproteínas/química , Fosfoproteínas/inmunología , Embarazo
19.
Neurophysiol Clin ; 26(6): 350-62, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-9018697

RESUMEN

Positive temporal sharp waves (PTS) were studied in electroencephalograms (EEG) of 92 premature infants born either at 31 and 32 weeks of gestational age, recorded during the first week of life. The infants were assigned either to a reference group (asymptomatic) or to one of three pathologic groups (neonatal asphyxia, hypoglycemia or hypocalcemia, or periventricular leukomalacia with rolandic positive sharp waves). Regardless of the group, no significant differences in PTS criteria (morphology, frequency, amplitude, duration and lateralization) were found between 31- and 32-week infants. The PTS observed in 55% of the asymptomatic infants were characterized by low frequency (0.13 +/- 0.12/min), a mean amplitude of 109.8 +/- 25.8 microV and a mean duration of 148.7 +/- 35.4 ms. For PTS recorded in 72 to 75% of pathologic infants, mean duration and amplitude were significantly greater in all groups than in asymptomatic infants, whereas frequency was significantly greater only in the group presenting with asphyxia. Discriminant analysis based on the three PTS criteria (frequency, amplitude and duration) allowed correct classification for only 30 to 54% of infants in the four groups. The frequency of PTS decreased rapidly during the second week of life in asymptomatic infants, but persisted in a larger number of infants in the pathologic groups. This study shows that PTS have no negative significance when they are few in number, short in duration, moderate in amplitude and rapidly regressive, thus probably reflecting the vulnerability of the temporal lobe during the traumatic period of birth. However, they require attention when they are abundant and/or slow, ample or tend to persist. They may thus constitute a nonspecific response to injury to an immature brain.


Asunto(s)
Electroencefalografía , Enfermedades del Prematuro/fisiopatología , Recien Nacido Prematuro/fisiología , Lóbulo Temporal/fisiología , Asfixia Neonatal/fisiopatología , Estudios de Casos y Controles , Análisis Discriminante , Edad Gestacional , Humanos , Hipocalcemia/fisiopatología , Hipoglucemia/fisiopatología , Recién Nacido , Lóbulo Temporal/fisiopatología
20.
Neurophysiol Clin ; 26(6): 414-22, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-9018700

RESUMEN

Thirty-five normal two-month-old infants had nighttime followed by daytime polygraphic recordings. Heart rates were calculated every minute in active and quiet sleep states. A difference in mean heart rates was found between the two states and between the two recordings. Rates were lower at night than during the day (P < 0.0001), regardless of the sleep state. During nighttime or daytime recordings as a function of sleep cycles or during sustained sleep episodes, heart rates were minimal in the middle of recordings, but differences were statistically significant for only a few results (mainly in QS). Intrasleep awakening led to a marked increase in heart rate after sleep was resumed, although differences were only statistically significant when the awakened infant was fed. Infants with episodes of periodic breathing had lower mean heart rates throughout the recordings, but differences were not statistically significant. Respiratory and heart rates showed similar changes during the recordings, and a statistically significant correlation was found between the two measurements.


Asunto(s)
Ritmo Circadiano/fisiología , Frecuencia Cardíaca/fisiología , Sueño/fisiología , Femenino , Humanos , Lactante , Masculino , Valores de Referencia , Respiración/fisiología , Mecánica Respiratoria/fisiología , Estadísticas no Paramétricas
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