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1.
Brain ; 133(Pt 3): 701-12, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20207700

RESUMEN

Neurodegeneration with brain iron accumulation encompasses a heterogeneous group of rare neurodegenerative disorders that are characterized by iron accumulation in the brain. Severe generalized dystonia is frequently a prominent symptom and can be very disabling, causing gait impairment, difficulty with speech and swallowing, pain and respiratory distress. Several case reports and one case series have been published concerning therapeutic outcome of pallidal deep brain stimulation in dystonia caused by neurodegeneration with brain iron degeneration, reporting mostly favourable outcomes. However, with case studies, there may be a reporting bias towards favourable outcome. Thus, we undertook this multi-centre retrospective study to gather worldwide experiences with bilateral pallidal deep brain stimulation in patients with neurodegeneration with brain iron accumulation. A total of 16 centres contributed 23 patients with confirmed neurodegeneration with brain iron accumulation and bilateral pallidal deep brain stimulation. Patient details including gender, age at onset, age at operation, genetic status, magnetic resonance imaging status, history and clinical findings were requested. Data on severity of dystonia (Burke Fahn Marsden Dystonia Rating Scale-Motor Scale, Barry Albright Dystonia Scale), disability (Burke Fahn Marsden Dystonia Rating Scale-Disability Scale), quality of life (subjective global rating from 1 to 10 obtained retrospectively from patient and caregiver) as well as data on supportive therapy, concurrent pharmacotherapy, stimulation settings, adverse events and side effects were collected. Data were collected once preoperatively and at 2-6 and 9-15 months postoperatively. The primary outcome measure was change in severity of dystonia. The mean improvement in severity of dystonia was 28.5% at 2-6 months and 25.7% at 9-15 months. At 9-15 months postoperatively, 66.7% of patients showed an improvement of 20% or more in severity of dystonia, and 31.3% showed an improvement of 20% or more in disability. Global quality of life ratings showed a median improvement of 83.3% at 9-15 months. Severity of dystonia preoperatively and disease duration predicted improvement in severity of dystonia at 2-6 months; this failed to reach significance at 9-15 months. The study confirms that dystonia in neurodegeneration with brain iron accumulation improves with bilateral pallidal deep brain stimulation, although this improvement is not as great as the benefit reported in patients with primary generalized dystonias or some other secondary dystonias. The patients with more severe dystonia seem to benefit more. A well-controlled, multi-centre prospective study is necessary to enable evidence-based therapeutic decisions and better predict therapeutic outcomes.


Asunto(s)
Encefalopatías/terapia , Encéfalo/fisiopatología , Estimulación Encefálica Profunda/métodos , Distonía/terapia , Hierro/metabolismo , Enfermedades Neurodegenerativas/terapia , Adolescente , Adulto , Encefalopatías/fisiopatología , Niño , Preescolar , Estimulación Encefálica Profunda/efectos adversos , Distonía/fisiopatología , Femenino , Lateralidad Funcional , Globo Pálido/fisiopatología , Humanos , Lactante , Masculino , Enfermedades Neurodegenerativas/fisiopatología , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
2.
Rev Med Suisse ; 4(146): 523-4, 526, 528, 2008 Feb 27.
Artículo en Francés | MEDLINE | ID: mdl-18402404

RESUMEN

Pediatric migraine differs from adult migraine especially in regards to duration, localisation and quality of pain. A detailed description of the symptoms with a normal neurological examination allows in most cases to rule out secondary headaches without other exams. Many different medications are used for symptomatic or prophylactic treatment with success. Symptomatic headaches should be suspected if there is any abnormality in history or neurological exam. Headaches due to arterial hypertension, ENT problems or maxillofacial causes should not be forgotten. Intracranial hypertension should be excluded especially in children with ventriculo-peritoneal shunt, since shunt dysfunction can be fatal. Post traumatic headache can be impressive but have a good prognosis.


Asunto(s)
Cefalea/diagnóstico , Trastornos Migrañosos/diagnóstico , Niño , Traumatismos Craneocerebrales/complicaciones , Cefalea/clasificación , Cefalea/etiología , Humanos , Hipertensión/complicaciones , Hipertensión Intracraneal/complicaciones , Trastornos Migrañosos/clasificación , Trastornos Migrañosos/etiología , Factores de Tiempo
3.
Neuropediatrics ; 37(1): 13-9, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16541363

RESUMEN

AIM: The aim of this study was to obtain information about neurological and cognitive outcome for a population-based group of children after paediatric ischaemic stroke. METHODS: Data from the Swiss neuropaediatric stroke registry (SNPSR), from 1.1.2000 to 1.7.2002, including children (AIS 1) and neonates (AIS 2). At 18-24 months after a stroke, a follow-up examination was performed including a history, neurological and neuropsychological assessment. RESULTS: 33/48 children (22 AIS 1, 11 AIS 2) participated in the study. Neurological outcome was good in 16/33. After childhood stroke mean IQ levels were normal (94), but 6 children had IQ < 85 (50-82) and neuropsychological problems were present in 75%. Performance IQ (93) was reduced compared to verbal IQ (101, p = 0.121) due to problems in the domain of processing speed (89.5); auditory short-term memory was especially affected. Effects on school career were common. Outcome was worse in children after right-sided infarction. Children suffering from stroke in mid-childhood had the best prognosis. There was no clear relationship between outcome and localisation of the lesion. After neonatal stroke 7/11 children showed normal development and epilepsy indicated a worse prognosis in the remaining 4. CONCLUSION: After paediatric stroke neuropsychological problems are present in about 75% of children. Younger age at stroke as well as an emergence of epilepsy were predictors for worse prognosis.


Asunto(s)
Inteligencia/fisiología , Procesos Mentales/fisiología , Pruebas Neuropsicológicas/estadística & datos numéricos , Accidente Cerebrovascular/fisiopatología , Adolescente , Factores de Edad , Infarto Encefálico/patología , Infarto Encefálico/fisiopatología , Niño , Preescolar , Escolaridad , Femenino , Estudios de Seguimiento , Humanos , Pruebas de Inteligencia , Masculino , Evaluación de Resultado en la Atención de Salud , Caracteres Sexuales , Suiza/epidemiología
4.
Neuropediatrics ; 35(1): 10-9, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15002047

RESUMEN

In 1988 we reported two sisters with bilateral Coats' disease, sparse hair, dystrophic nails, and primeval splashes of intracranial calcification. We now provide an update on this family documenting the occurrence of skeletal defects comprising abnormal bone marrow, osteopenia, and sclerosis with a tendency to fractures, a mixed cerebellar and extrapyramidal movement disorder, infrequent epileptic seizures, leukodystrophic changes, and postnatal growth failure. Additionally, we present two previously unreported individuals from Ireland and Switzerland with the identical disorder which we designate Coats' plus. Since our original publication a number of other authors have described, frequently as a "new" syndrome, cases with a variable combination of the same features observed in our patients. We review this literature and suggest that the phenotypic overlap with dyskeratosis congenita may provide a clue to the molecular aetiology of this multisystem disorder.


Asunto(s)
Alopecia/complicaciones , Médula Ósea/anomalías , Encéfalo/patología , Calcinosis/complicaciones , Disqueratosis Congénita/complicaciones , Trastornos del Crecimiento/complicaciones , Leucoencefalopatía Multifocal Progresiva/complicaciones , Leucoencefalopatía Multifocal Progresiva/patología , Uñas Malformadas , Encéfalo/diagnóstico por imagen , Calcinosis/diagnóstico por imagen , Calcinosis/patología , Niño , Disqueratosis Congénita/patología , Femenino , Humanos , Leucoencefalopatía Multifocal Progresiva/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Tomografía Computarizada por Rayos X
5.
Neuropediatrics ; 35(1): 50-3, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15002053

RESUMEN

A 2-year-old boy presented with an early form of benign partial epilepsy with centro-temporal spikes (BCERS) and a severe speech delay. Family video analysis revealed an early regression of babbling and stagnation since the age of 12 months. Complete recovery occurred with anti-epileptic treatment. The deficit corresponded to a transient speech apraxia attributed to an epileptic disconnection of networks coordinating speech articulation. This observation is, to the best of our knowledge, the first demonstration that delayed emergence of language can be due to an epileptic dysfunction interfering with prelinguistic skills and therefore mimicking a developmental delay.


Asunto(s)
Epilepsia del Lóbulo Temporal/complicaciones , Trastornos del Lenguaje/etiología , Trastornos del Habla/etiología , Preescolar , Electroencefalografía , Epilepsia del Lóbulo Temporal/diagnóstico , Humanos , Trastornos del Lenguaje/diagnóstico , Pruebas del Lenguaje , Masculino , Pruebas Neuropsicológicas , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Trastornos del Habla/diagnóstico
6.
Ann Neurol ; 48(5): 745-57, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11079538

RESUMEN

Multi-minicore disease (MmD) is a congenital myopathy morphologically defined by the presence of multiple small zones of sarcomeric disorganization and lack of oxidative activity ("minicores") in muscle fibers. The dinical expression of MmD is considered to be greatly variable, and the morphological lesions are nonspecific; therefore, its boundaries are poorly defined, and its molecular bases are not known. To better define the phenotypic characteristics of MmD, we analyzed a large series of 38 patients with multiple minicores in muscle fibers in the absence of any other potential cause. According to clinical features, 4 subgroups were identified. Most patients (30 cases) shared a common highly consistent phenotype marked by the axial predominance of muscle weakness and a high occurrence of severe respiratory insufficiency and scoliosis ("classical" form). Other forms were characterized by pharyngolaryngeal involvement and total lack of head control (2 cases), antenatal onset with arthrogryposis (3 cases), and slowly progressive weakness with marked hand amyotrophy (3 cases). Type 1 fiber predominance and hypotrophy as well as centrally located nuclei were found in every subgroup. MmD is thus phenotypically heterogeneous, but a typical recognizable phenotype does exist. This phenotype classification should be helpful when undertaking research into the molecular defects that cause MmD.


Asunto(s)
Músculos/patología , Enfermedades Musculares/genética , Enfermedades Musculares/patología , Biopsia , Femenino , Humanos , Masculino , Fenotipo , Estudios Retrospectivos
7.
Eur J Paediatr Neurol ; 4(4): 171-6, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11008260

RESUMEN

We report clinical, neuroradiological and neuropathological findings of monozygotic twin sisters born at 30 weeks' gestation, with pontocerebellar hypoplasia (PCH) similar but not identical to type 2 PCH. They presented with hypertonia, jitteriness, spontaneous and provoked myoclonic jerks (hyperekplexia), apnoeic episodes, and progressive microcephaly. They died at 7 weeks of age from respiratory failure.


Asunto(s)
Encefalopatías/diagnóstico , Cerebelo/anomalías , Enfermedades en Gemelos , Enfermedades del Prematuro , Puente/anomalías , Encefalopatías/patología , Cerebelo/patología , Contractura/etiología , Diagnóstico Diferencial , Progresión de la Enfermedad , Femenino , Humanos , Recién Nacido , Imagen por Resonancia Magnética , Microcefalia/etiología , Hipertonía Muscular/etiología , Mioclonía/etiología , Núcleo Olivar/patología , Puente/patología , Reflejo Anormal , Gemelos Monocigóticos
8.
Proc Natl Acad Sci U S A ; 97(13): 7627-32, 2000 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-10861024

RESUMEN

Mechanisms underlying Ca(2+) signaling during human myoblast terminal differentiation were studied using cell cultures. We found that T-type Ca(2+) channels (T-channels) are expressed in myoblasts just before fusion. Their inhibition by amiloride or Ni(2+) suppresses fusion and prevents an intracellular Ca(2+) concentration increase normally observed at the onset of fusion. The use of antisense oligonucleotides indicates that the functional T-channels are formed by alpha1H subunits. At hyperpolarized potentials, these channels allow a window current sufficient to increase [Ca(2+)](i). As hyperpolarization is a prerequisite to myoblast fusion, we conclude that the Ca(2+) signal required for fusion is produced when the resting potential enters the T-channel window. A similar mechanism could operate in other cell types of which differentiation implicates membrane hyperpolarization.


Asunto(s)
Canales de Calcio Tipo T/metabolismo , Calcio/metabolismo , Músculo Esquelético/metabolismo , Diferenciación Celular , Células Cultivadas , Humanos , Transporte Iónico , Músculo Esquelético/citología , Transducción de Señal
9.
Schweiz Med Wochenschr Suppl ; 116: 8S-11S, 2000.
Artículo en Francés | MEDLINE | ID: mdl-10780061

RESUMEN

OBJECTIVE: To evaluate and compare the performances of FDG-PET imaging, MRI and clinical examination in the detection of residual tumour 3 months after treatment of patients with head and neck squamous cell carcinoma. PATIENTS: A consecutive sample of 50 patients with squamous cell carcinoma of the oral cavity, oropharynx, hypopharynx or larynx, or a cervical lymph node metastasis from an unknown primary site excluding T1 lip and T1 vocal cord tumours. METHODS: Treatment outcome was assessed after 3 months by clinical examination, MRI, and FDG-PET scan. Sensitivity, specificity and accuracy were calculated relative to proven biopsy of residual tumour or a clinical follow-up of 4 months. RESULTS: Residual cancer was confirmed in 8 patients (16%), while the clinical follow-up was unsuspicious in the remaining 42 patients. PET-FDG had a sensitivity of 100% as compared to MRI (88%) and clinical examination (63%). Specificity was higher for clinical examination (90%), intermediate for MRI (83%) and lowest for PET-FDG (74%). CONCLUSIONS: This study finds very high sensitivity for PET-FDG in the detection of residual tumour. However, its lower specificity, lack of anatomical resolution, and high cost, require further studies to determine its role in routine screening.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico por imagen , Neoplasias Laríngeas/diagnóstico por imagen , Recurrencia Local de Neoplasia/diagnóstico por imagen , Neoplasia Residual/diagnóstico por imagen , Neoplasias Orofaríngeas/diagnóstico por imagen , Tomografía Computarizada de Emisión , Biopsia , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/terapia , Medios de Contraste , Femenino , Fluorodesoxiglucosa F18 , Humanos , Neoplasias Laríngeas/patología , Neoplasias Laríngeas/terapia , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/terapia , Estadificación de Neoplasias , Neoplasia Residual/patología , Neoplasia Residual/terapia , Neoplasias Orofaríngeas/patología , Neoplasias Orofaríngeas/terapia , Valor Predictivo de las Pruebas
11.
Nuklearmedizin ; 39(8): 246-50, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11189902

RESUMEN

AIM: The objective of this study was to compare screening ultrasound (US) obtained in patients with squamous cell carcinoma of the head and neck with F-18-FDG PET and to evaluate if US obtained before F-18-FDG PET has the potential to enhance patient management by the detection of additional lesions. METHOD: 28 patients were prospectively included in the study (7 females and 21 males; range: 28-82 years). All had one follow-up examination after surgical treatment and/or radiotherapy using a combination of US and F-18-FDG PET on the same day (6-35 months after the end of treatment). Outcome was determined by either biopsyproven cancer recurrence or negative clinical follow-up for additional 6 months after this examination. RESULTS: Regarding only the regions of the neck evaluated with both methods, US detected 25 suspect lesions vs. 9 lesions detected by F-18-FDG PET. Descriptive statistical analysis showed better sensitivity, specificity and accuracy of F-18-FDG PET. Only in 3 patients a lesion was detected in the same anatomical region using both methods. One patient was false positive with both methods. In another patient US detected a calcified right carotid artery plaque that lead to surgical therapy. CONCLUSION: F-18-FDG PET is better for the detection of clinically relevant lesions in the follow-up of patients with squamous cell carcinoma of the head and neck. In this study, the additional value of morphological information obtained by screening US performed before the PET scan is limited. US may not be a suitable test to improve interpretation of PET examinations.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/cirugía , Reacciones Falso Positivas , Femenino , Fluorodesoxiglucosa F18 , Estudios de Seguimiento , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico por imagen , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Radiografía , Radiofármacos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Tomografía Computarizada de Emisión , Ultrasonografía
13.
J Neurol ; 246(8): 667-70, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10460442

RESUMEN

Several plant-derived essential oils have been known for over a century to have epileptogenic properties. We report three healthy patients, two adults and one child, who suffered from an isolated generalized tonic-clonic seizure and a generalized tonic status, respectively, related to the absorption of several of these oils for therapeutic purposes. No other cause of epilepsy was found, and outcome was good in the two adult cases, but the course has been less favorable in the child. A survey of the literature shows essential oils of 11 plants to be powerful convulsants (eucalyptus, fennel, hyssop, pennyroyal, rosemary, sage, savin, tansy, thuja, turpentine, and wormwood) due to their content of highly reactive monoterpene ketones, such as camphor, pinocamphone, thujone, cineole, pulegone, sabinylacetate, and fenchone. Our three cases strongly support the concept of plant-related toxic seizure. Nowadays the wide use of these compounds in certain unconventional medicines makes this severe complication again possible.


Asunto(s)
Epilepsia Tónico-Clónica/inducido químicamente , Aceites Volátiles/efectos adversos , Aceites de Plantas/efectos adversos , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Factores de Riesgo
14.
Electroencephalogr Clin Neurophysiol ; 106(6): 508-12, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9741750

RESUMEN

We present a new approach for non-invasive localization of focal epileptogenic discharges in patients considered for surgical treatment. EEG-triggered functional MR imaging (fMRI) and 3D EEG source localization were combined to map the primary electrical source with high spatial resolution. The method is illustrated by the case of a patient with medically intractable frontal lobe epilepsy. EEG obtained in the MRI system allowed triggering of the fMRI acquisition by the patient's habitual epileptogenic discharges. fMRI revealed multiple areas of signal enhancement. Three-dimensional EEG source localization identified the same active areas and provided evidence of onset in the left frontal lobe. Subsequent electrocorticography from subdural electrodes confirmed spike and seizure onset over this region. This approach, i.e. the combination of EEG-triggered fMRI and 3D EEG source analysis, represents a promising additional tool for presurgical epilepsy evaluation allowing precise non-invasive identification of the epileptic foci.


Asunto(s)
Electroencefalografía/métodos , Epilepsias Parciales/fisiopatología , Epilepsia del Lóbulo Frontal/fisiopatología , Imagen por Resonancia Magnética/métodos , Magnetoencefalografía/métodos , Adolescente , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Tomografía
15.
J Med Genet ; 35(3): 211-7, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9541105

RESUMEN

Classical congenital muscular dystrophy with merosin deficiency is caused by mutations in the laminin alpha2 chain gene (LAMA2). Extended sequencing of the introns flanking the 64 LAMA2 exons was carried out and, based on these sequences, oligonucleotide primers were designed to amplify the coding region of each exon separately. By PCR-SSCP analysis, we identified eight new mutations in nine families originating from various countries. All induced a premature truncation of the protein, either in the short arm or in the globular C-terminal domain. A 2 bp deletion in exon 13, 2098delAG, was found in three French non-consanguineous families and a nonsense mutation of exon 20, Cys967stop, in two other non-consanguineous families originating from Italy. Determination of rare intragenic polymorphisms permitted us to show evidence of founder effects for these two mutations suggesting a remote degree of consanguinity between the families. Other, more frequent polymorphisms, G to A 1905 (exon 12), A to G 2848 (exon 19), A to G 5551 (exon 37), and G to A 6286 (exon 42), were used as intragenic markers for prenatal diagnosis. This study provides valuable methods for determining the molecular defects in LAMA2 causing merosin deficient congenital muscular dystrophy.


Asunto(s)
Efecto Fundador , Laminina/genética , Distrofias Musculares/genética , Diagnóstico Prenatal , Niño , Análisis Mutacional de ADN , Cartilla de ADN , Exones , Femenino , Haplotipos , Humanos , Intrones , Masculino , Repeticiones de Microsatélite , Distrofias Musculares/congénito , Distrofias Musculares/diagnóstico , Mutación , Linaje , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Polimorfismo Conformacional Retorcido-Simple , Análisis de Secuencia de ADN
16.
Audiology ; 36(4): 202-27, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9253480

RESUMEN

The activity of single neurons (n = 182) of the central nucleus of the inferior colliculus (CIC) of the rat was recorded in response to unilateral electrical stimulation of the left cochlea and/or acoustical stimulation of the right ear. The probability of response to both modes of stimulation was comparable (90 per cent for contralateral and 60 per cent for ipsilateral presentation). Response patterns consisted predominantly of onset excitations. Response latencies to electrical stimuli ranged from 3 to 21 ms, with an average value of 9.7 ms (SD = 3.5 ms) in the ipsilateral CIC and 6.6 ms (SD = 3.4 ms) in the contralateral CIC. With respect to binaural inputs, the majority of units were excited by stimulation of either ear (EE; about 60 per cent) while about one third were influenced by one ear only (EO). Units excited by one ear and inhibited by the other (EI) were rare. The main difference between the present implanted rats and normal animals was the virtual absence here of inhibitory effects for both types of stimuli when they were delivered to the ipsilateral ear (very few EI units).


Asunto(s)
Cóclea/fisiología , Colículos Inferiores/fisiología , Estimulación Acústica , Animales , Estimulación Eléctrica , Electrodos Implantados , Potenciales Evocados Auditivos del Tronco Encefálico , Lateralidad Funcional , Neuronas/fisiología , Ratas
18.
Neuropediatrics ; 27(6): 323-5, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9050051

RESUMEN

A 15-year-old adolescent with pneumococcal meningitis and increased intracranial pressure presented clinical and neurophysiological evidence of the locked-in syndrome. MRI studies showed an area of infarction involving the ventral part of the medulla.


Asunto(s)
Meningitis Neumocócica/complicaciones , Cuadriplejía/complicaciones , Cuadriplejía/diagnóstico , Adolescente , Encéfalo/patología , Encefalocele/complicaciones , Encefalocele/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Cuadriplejía/patología , Vasculitis/complicaciones , Vasculitis/patología
19.
J Physiol ; 493 ( Pt 1): 129-41, 1996 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-8735699

RESUMEN

1. Using the patch-clamp technique, a new non-inactivating voltage-gated potassium current, IK(ni), was studied in cultured fusion-competent human myoblasts. 2. IK(ni) is activated at voltages above -50 mV and its conductance reaches its maximum around +50 mV. Once activated, the current remains at a steady level for minutes. 3. Reversal potential measurements at various extracellular potassium concentrations indicate that potassium ions are the major charge carriers of IK(ni). 4. IK(ni) is insensitive to potassium channel blockers such as charybdotoxin, dendrotoxins, mast cell degranulating (MCD) peptide, 4-aminopyridine (4-AP), 3,4-diaminopyridine (3,4-DAP) and apamin, but can be blocked by high concentrations of TEA and by Ba2+. 5. A potassium channel of small conductance (8.4 pS at +40 mV) with potential dependence and pharmacological properties corresponding to those of IK(ni) in whole-cell recording is described. 6. IK(ni) participates in the control of the resting potential of fusion-competent myoblasts, suggesting that it may play a key role in the process of myoblast fusion.


Asunto(s)
Fusión Celular/fisiología , Potenciales de la Membrana/fisiología , Músculo Esquelético/metabolismo , Canales de Potasio/metabolismo , Potasio/metabolismo , Adolescente , Adulto , Aminopiridinas/farmacología , Células Cultivadas , Caribdotoxina/farmacología , Niño , Preescolar , Venenos Elapídicos/farmacología , Electrofisiología , Humanos , Lactante , Músculo Esquelético/citología , Técnicas de Placa-Clamp , Péptidos/farmacología , Bloqueadores de los Canales de Potasio
20.
Brain Res Bull ; 39(2): 75-82, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8846116

RESUMEN

The goal of the present study was to establish how Fos-like immunoreactivity (FLI) elicited in the rat auditory pathway by unilateral electric stimulation of the cochlea is affected by the following experimental parameters: duration and intensity of stimulation, duration of survival time after offset of stimulation. The dense FLI found in the ipsilateral dorsal cochlear nucleus, as well as the moderate FLI found in the contralateral dorsal cochlear nucleus and in the posteroventral cochlear nucleus on both sides, were consistent after survival times ranging from 0 to 2-3 h, but they significantly decreased after longer survival times (5 and 6 h). In the same nuclei, FLI was increased even by short durations of stimulation (5 and 10 min) as compared to control rats, although FLI progressively increased for longer stimulation (20 and 45 min). In the auditory thalamus, FLI was found mainly in the peripeduncular nucleus, the dorsal and medial divisions of the medial geniculate body, whereas its ventral division was virtually devoid of immunoreactive neurons. This pattern of FLI distribution in the auditory thalamus persisted even after relatively long survival times (5 and 6 h). In both the cochlear nucleus and auditory thalamus, the density of FLI slightly increased in parallel with the intensity of stimulation. In other auditory nuclei, such as the inferior colliculus and the nucleus of the lateral lemniscus, there was no simple relation between the density of FLI and the three tested experimental parameters. Thus, the distribution and density of FLI did not vary in parallel in the various nuclei of the auditory pathway as a function of the tested experimental parameters; different patterns of FLI changes were instead observed in different auditory nuclei.


Asunto(s)
Vías Auditivas/fisiología , Proteínas Proto-Oncogénicas c-fos/metabolismo , Potenciales de Acción/fisiología , Animales , Vías Auditivas/anatomía & histología , Vías Auditivas/metabolismo , Implantes Cocleares , Núcleo Coclear/metabolismo , Núcleo Coclear/fisiología , Estimulación Eléctrica , Femenino , Inmunohistoquímica , Colículos Inferiores/metabolismo , Colículos Inferiores/fisiología , Masculino , Ratas , Ratas Sprague-Dawley , Sobrevida , Núcleos Talámicos/metabolismo , Núcleos Talámicos/fisiología , Núcleos Vestibulares/metabolismo , Núcleos Vestibulares/fisiología
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