Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
Más filtros

Bases de datos
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Mov Disord ; 26(4): 691-8, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21312284

RESUMEN

Deep brain stimulation of the globus pallidus internus (GPi DBS) is effective in the treatment of primary segmental and generalized dystonia. Although limb, neck, or truncal dystonia are markedly improved, orofacial dystonia is ameliorated to a lesser extent. Nevertheless, several case reports and small cohort studies have described favorable short-term results of GPi DBS in patients with severe Meige syndrome. Here, we extend this preliminary experience by reporting long-term outcome in a multicenter case series, following 12 patients (6 women, 6 men) with Meige syndrome for up to 78 months after bilateral GPi DBS. We retrospectively assessed dystonia severity based on preoperative and postoperative video documentation. Mean age of patients at surgery was 64.5 ± 4.4 years, and mean disease duration 8.3 ± 4.4 years. Dystonia severity as assessed by the Burke-Fahn-Marsden Dystonia Rating Scale showed a mean improvement of 45% at short-term follow-up (4.4 ± 1.5 months; P < 0.001) and of 53% at long-term follow-up (38.8 ± 21.7 months; P < 0.001). Subscores for eyes were improved by 38% (P = 0.004) and 47% (P < 0.001), for mouth by 50% (P < 0.001) and 56% (P < 0.001), and for speech/swallowing by 44% (P = 0.058) and 64% (P = 0.004). Mean improvements were 25% (P = 0.006) and 38% (P < 0.001) on the Blepharospasm Movement Scale and 44% (P < 0.001) and 49% (P < 0.001) on the Abnormal Involuntary Movement Scale. This series, which is the first to demonstrate a long-term follow-up in a large number of patients, shows that GPi DBS is a safe and highly effective therapy for Meige syndrome. The benefit is preserved for up to 6 years.


Asunto(s)
Estimulación Encefálica Profunda/métodos , Globo Pálido/fisiología , Síndrome de Meige/terapia , Anciano , Análisis de Varianza , Electrodos , Femenino , Humanos , Estudios Longitudinales , Masculino , Síndrome de Meige/fisiopatología , Persona de Mediana Edad , Actividad Motora/fisiología , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
2.
Pain Ther ; 9(2): 615-626, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32910427

RESUMEN

INTRODUCTION: Occipital nerve stimulation (ONS) is used to treat therapy-resistant chronic migraine. Clinical use has resulted in a wide intraindividual and interindividual variation of clinical efficacy. The aim of this study was to analyze a potential relationship between sociodemographic variables, headache parameters, perceived sensory quality, perceived sensory location, as well as clinical efficacy. METHODS: Thirty-two subjects (21.9% male, mean age 45.77 years) suffering from chronic migraine refractory to other treatment and therefore treated with ONS were included in this study. We used a computer-based imaging method for mapping the ONS-induced perceived sensory location, the perceived spatial sensory field size, as well as the perceived sensory quality in a long-term course over 21 months in weekly time intervals. Additionally, the effect of ONS on the migraine headache was documented weekly by the participants using a verbal rating scale. Over the observation period, a total of 808 individual weekly data sets were recorded and a potential relationship between ONS-induced perceptions and headache parameters could be analyzed. RESULTS: We found that 48.9% of stimulation intervals were reported as effective by patients. Women displayed a significantly higher responder rate than men. The reported effectiveness did not differ depending on age, the average number of migraine days per month, the MIDAS score, or the duration of the migraine disorder prior to ONS treatment. Implantation with trial period led to significantly lower responder rates than without the trial period. The most frequently perceived sensory quality of "tingling" was found significantly more frequently in non-responders than in responders. Responders displayed significantly lower pleasantness scores for their reported perceptions than non-responders. Sensations that were spatially perceived above the line connecting the external acoustic meati with the external occipital protuberance (MOP line) led to patients reporting a positive clinical effect significantly more frequently than sensations spatially perceived below the MOP line. Spatially small fields of sensory perception were correlated with a higher responder rate than those covering broader areas. CONCLUSIONS: The ONS-induced sensory location, the size of the spatial sensory field, as well as the sensory quality are significantly correlated with the reported clinical effectiveness. The results suggest that besides surgical technique, the individual and continuous programming of the stimulation parameters is clinically relevant in increasing the therapeutic effectiveness.

4.
J Neurotrauma ; 25(5): 427-48, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18338959

RESUMEN

Spinal cord injury (SCI) often results in intractable chronic central pain syndromes. Recently chemokines such as CCL2 were identified as possible key integrators of neuropathic pain and inflammation after peripheral nerve lesion. The focus of the current study was the investigation of time-dependent CCL2 and CCR2 expression in relation to central neuropathic pain development after spinal cord impact lesions of 100, 150, or 200 kdyn force on spinal cord level T9 in adult rats. Below-level pain was monitored with weekly sensory testing for 42 days after SCI. In parallel expression of CCL2/CCR2 on cervical, thoracic, and lumbar levels was investigated by real-time reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemistry early (7 days [7d]), intermediate (15d), and late (42d) after lesion. Cellular source and anatomical pain related expression was determined by double-immunohistochemistry. Force-defined SCI led to acute mechanical hypersensitivity in all lesion groups, and to persistent below-level pain in severely injured animals. While in the early post-operative time course, CCL2 and CCR2 were expressed in astroglia and granulocytes only on level T9; there was additional astroglial CCL2 expression in dorsal columns and dorsal horns above and below T9 of severely injured animals 42d after lesion. In dorsal horns (level L3-L5) of animals exhibiting chronic below-level pain CCL2 was co-expressed with transmitters and receptors that are involved in nociceptive processing like calcitonin gene-related peptide (CGRP), Substance-P, vanilloid-receptor-1, and its activated phosphorylated form. These data demonstrate lesion grade dependence of below-level pain development and suggest chemokines as potential candidates for integrating inflammation and central neuropathic pain after SCI.


Asunto(s)
Quimiocina CCL2/biosíntesis , Neuralgia/metabolismo , Receptores CCR2/biosíntesis , Traumatismos de la Médula Espinal/metabolismo , Traumatismos de la Médula Espinal/fisiopatología , Animales , Péptido Relacionado con Gen de Calcitonina/biosíntesis , Expresión Génica , Hiperalgesia/metabolismo , Hiperalgesia/patología , Hiperalgesia/fisiopatología , Inmunohistoquímica , Inflamación/metabolismo , Inflamación/patología , Inflamación/fisiopatología , Región Lumbosacra , Masculino , Actividad Motora/fisiología , Neuralgia/fisiopatología , Dimensión del Dolor , ARN Mensajero/análisis , Ratas , Ratas Endogámicas LEC , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Traumatismos de la Médula Espinal/patología , Sustancia P/biosíntesis , Canales Catiónicos TRPV/biosíntesis , Vértebras Torácicas , Tiempo
5.
J Neurosurg Sci ; 60(2): 199-210, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26977634

RESUMEN

Deep brain stimulation (DBS) has become one of the major therapy options for movement disorders including dystonia. This article should give a review of the current literature from a neurosurgical perspective. Since dystonia is a rare disease, only few studies on larger cohorts have been published, and very few randomized controlled studies are avaialable in the international literature. Our experiences gained treating 134 patients with various types of dystonia, between 1999 and 2015, will serve a guide to interpret the current literature. Symptoms of dystonia are due to a variety of medical conditions. A careful and extensive neurological evaluation is mandatory before medical and surgical treatment options are considered, since the clinical benefits of more aggressive treatment e.g. by DBS depend to a large extent on the etiology of the disease. Diagnostic steps should include also magnetic resonance imaging (MRI) and possibly genetic evaluation. Therapy consists of physiotherapy, medical therapy including botulinum toxin injections in focal dystonia and DBS. This neurosurgical therapy is considered a highly effective therapy in well selected patients, which should be discussed, depending on the etiology, early in the patient's career. Patients with primary dystonia will benefit the most from DBS to the ventromediolateral part of the globus pallidus internus (GPi) with acceptable low complication rates; in order to optimize longterm results in these groups of patient, they will require an interdisciplinary individualized approach both pre- and postoperatively as well as longterm care adjusting to their needs.


Asunto(s)
Estimulación Encefálica Profunda , Distonía/terapia , Globo Pálido/cirugía , Vías Nerviosas/fisiopatología , Estimulación Encefálica Profunda/métodos , Humanos , Imagen por Resonancia Magnética/métodos , Resultado del Tratamiento
6.
Clin Neurol Neurosurg ; 147: 39-45, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27276340

RESUMEN

OBJECTIVES: Awake craniotomy is a well-established procedure in surgery of intracranial tumors in eloquent areas. However, sufficiently standardized instruments for the assessment of sensory-motor function before, during and after the operation are currently lacking, despite their importance for evaluation of operative outcome. PATIENTS AND METHODS: To address this issue, we designed a standardized assessment tool (the "sensory-motor profile awake scale"; SMP-a). The final scale consists of three motor sections (face, arm and leg) assessing both gross and fine motor skills and one sensory section. It differentiates between six grades of impairment and its tasks are applicable for intraoperative continuous monitoring of sensory-motor functions and supporting processes. We analyzed the data of 17 patients with intracranial tumors eligible for awake craniotomy who were preoperatively assessed with the SMP-a. In addition, we present an exemplary case. RESULTS: Our data support the assumption that the SMP-a is feasible in patients eligible for awake craniotomy, even in patients with symptoms of mild aphasia or more severe sensory-motor deficits caused by tumor recurrence. The exemplary case demonstrates the feasibility of repeated measures with the SMP-a in a tumor patient, including the adaption of tasks to the individual requirements of an intraoperative setting. CONCLUSION: This exploratory study suggests that the SMP-a might be a feasible rating scale in patients with intracranial tumors. The flexibility of the scale enables individual adaption, but preserves the standardized scoring system to allow comparison between assessment dates, patients and, hopefully in the future, institutions. However, future studies are mandatory to provide data on the instrument's diagnostic properties with respect to feasibility, objectivity, validity and reliability.


Asunto(s)
Neoplasias Encefálicas/fisiopatología , Neoplasias Encefálicas/cirugía , Craneotomía/métodos , Monitorización Neurofisiológica/métodos , Evaluación de Procesos y Resultados en Atención de Salud/métodos , Periodo Perioperatorio , Adulto , Humanos , Monitorización Neurofisiológica Intraoperatoria/métodos , Vigilia
7.
Neurol Res ; 27(4): 371-7, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15949234

RESUMEN

INTRODUCTION: Vascular endothelial growth factor (VEGF) and its receptors VEGFR-1 and -2 are considered to play a major in tumor angiogenesis, which is a prerequisite for growth of solid tumors. Glioblastoma multiforme is a prominent example of VEGF-induced tumor vascularization; however, little is known about VEGF and in particular VEGFR expression in other types of brain tumors. METHODS: VEGFR mRNA was quantified by real time RT-PCR in 12 different types of brain tumors and compared to VEGF protein content measured by ELISA. VEGF splice variants were determined by an RT-PCR method. RESULTS: VEGF protein was highest in glioblastoma and metastatic kidney tumors. In all types of tumors the diffusible splice forms VEGF(121) and VEGF(165) were expressed; VEGF(189) was minor in a few tumors. Expression of VEGF receptors did not necessarily correlate with VEGF content. Both were highly expressed in glioblastomas, but in meningiomas VEGF was low and VEGFR high, and in metastatic tumors the reverse. With few exceptions, in particular oligodendrogliomas, VEGFR-1 expression was parallel to VEGFR-2 expression. Interestingly, for the astrocytic gliomas, the expression of VEGFR correlated well to the tumor malignancy, even better than VEGF content. CONCLUSIONS: These results show that VEGF and VEGFR expression in various types of brain tumors differ and are not necessarily parallel.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Regulación Neoplásica de la Expresión Génica/fisiología , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 1 de Factores de Crecimiento Endotelial Vascular/metabolismo , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Northern Blotting/métodos , Neoplasias Encefálicas/clasificación , Ensayo de Inmunoadsorción Enzimática/métodos , Ependimoma/metabolismo , Variación Genética , Glioblastoma/metabolismo , Humanos , Inmunohistoquímica/métodos , Neoplasias Renales/metabolismo , Melanoma/metabolismo , Oligodendroglioma/metabolismo , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Factor A de Crecimiento Endotelial Vascular/genética , Receptor 1 de Factores de Crecimiento Endotelial Vascular/genética , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genética
8.
Brain Stimul ; 8(2): 295-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25465289

RESUMEN

BACKGROUND: Within the last years, occipital nerve stimulation (ONS) has proven to be an important method in the treatment of severe therapy-resistant neurological pain disorders. The correspondence between lead placement as well as possible stimulation parameters and the resulting stimulation effects remains unclear. OBJECTIVE: The method aims to directly relate the neuromodulatory mechanisms with the clinical treatment results, to achieve insight in the mode of action of neuromodulation, to identify the most effective stimulation sets and to optimize individual treatment effects. METHODS: We describe a new computer-based imaging method for mapping the spatial, cognitive and affective sensory effects of ONS. The procedure allows a quantitative and qualitative analysis of the relationship between lead positioning, the stimulation settings as well as the sensory and clinical stimulation effects. CONCLUSION: A regular mapping of stimulation and sensory parameters allows a coordinated monitoring. The stimulation results can be reviewed and compared with regards to clinical effectiveness.


Asunto(s)
Mapeo Encefálico/métodos , Terapia por Estimulación Eléctrica/métodos , Imagenología Tridimensional/métodos , Nervios Periféricos/fisiología , Humanos
9.
Neurol Res ; 25(8): 853-6, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14669529

RESUMEN

Intracerebral hemorrhage (ICH) occurs in about 10%-15% of all strokes, and hypertension and cerebral amyloid angiopathy (CAA) are the main underlying causes. There is often controversy regarding surgical evacuation especially in elderly patients. Follow-up of these patients and regulation of hypertension is important to prevent re-bleeding. The number of recurrent hematomas will increase with time of follow-up. We reviewed 968 patients with an ICH treated in our Department and 48 patients with recurrent hemorrhages (4.9%). The mean interval between the first and the second hemorrhage was three years (one month to 10 years). Clinical outcome after a second hemorrhage was severe and only 50% of patients were operated on the second hemorrhage compared to 77% (37/48) of patients who were operated on the first hemorrhage.


Asunto(s)
Hemorragia Cerebral/epidemiología , Hemorragia Cerebral/prevención & control , Riesgo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticoagulantes/uso terapéutico , Angiopatía Amiloide Cerebral/complicaciones , Angiopatía Amiloide Cerebral/patología , Hemorragia Cerebral/etiología , Hemorragia Cerebral/patología , Niño , Preescolar , Enfermedad Coronaria/complicaciones , Enfermedad Coronaria/epidemiología , Complicaciones de la Diabetes , Diabetes Mellitus/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Hipertensión/complicaciones , Hipertensión/tratamiento farmacológico , Hipertensión/epidemiología , Lactante , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Recurrencia , Factores de Tiempo , Tomografía Computarizada por Rayos X
10.
Clin Pract ; 1(2): e29, 2011 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-24765291

RESUMEN

In the present case we report about an encephalomeningocele in an adult female. Since the cause of this medical entity is a congenital fusion defect of the neural tube of the cranial base, most of the encephaloceles occurs in children leading to facial disfigurement. In the rare cases described in adults, rhinorrhea is usually present. Here we present a case of temporobasal encephalomeningocele in a 72-year-old female patient suffering from headaches in the last 4-5 years. No rhinorrhea or other significant neurological symptoms were noticed. No congenital cause was apparent. After diagnostic steps including brain magnetic resonance imaging (MRI), cranial computed tomography (CT) and MR cisternography, an encephalomeningocele was diagnosed. Through a pterional approach this was completely removed. The only symptom the patient complaint about, headache, was eliminated after surgery.

11.
PLoS One ; 2(8): e762, 2007 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-17712410

RESUMEN

Is sexual orientation associated with structural differences in the brain? To address this question, 80 homosexual and heterosexual men and women (16 homosexual men and 15 homosexual women) underwent structural MRI. We used voxel-based morphometry to test for differences in grey matter concentration associated with gender and sexual orientation. Compared with heterosexual women, homosexual women displayed less grey matter bilaterally in the temporo-basal cortex, ventral cerebellum, and left ventral premotor cortex. The relative decrease in grey matter was most prominent in the left perirhinal cortex. The left perirhinal area also showed less grey matter in heterosexual men than in heterosexual women. Thus, in homosexual women, the perirhinal cortex grey matter displayed a more male-like structural pattern. This is in accordance with previous research that revealed signs of sex-atypical prenatal androgenization in homosexual women, but not in homosexual men. The relevance of the perirhinal area for high order multimodal (olfactory and visual) object, social, and sexual processing is discussed.


Asunto(s)
Encéfalo/anatomía & histología , Heterosexualidad , Homosexualidad Femenina , Homosexualidad Masculina , Caracteres Sexuales , Adolescente , Adulto , Animales , Mapeo Encefálico , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Adulto Joven
12.
Neuroimage ; 33(3): 825-33, 2006 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-16979350

RESUMEN

Sexually arousing visual stimuli activate the human reward system and trigger sexual behavior. Here we performed event-related fMRI during visual processing of sexual core stimuli to pinpoint a neuronal correlate of sexual preference in humans. To dissociate gender of the stimulus from sexual preference, we studied male and female heterosexual and homosexual volunteers while they viewed sexual and nonsexual control stimuli. In contrast to previous work, we used core single-sex stimuli displaying male and female sexually aroused genitals. Since stimuli lacked any additional contextual information, they evoked no activity related to neuronal processing of faces, gestures or social interactions. Our prediction was that the sexual preference of the observer determines the neuronal responsiveness to pure male or female sexual stimuli in the human reward and motor system. Consistent with our prediction, the ventral striatum and the centromedian thalamus, showed a stronger neuronal response to preferred relative to non-preferred stimuli. Likewise, the ventral premotor cortex which is a key structure for imitative (mirror neurons) and tool-related (canonical neurons) actions showed a bilateral sexual preference-specific activation, suggesting that viewing sexually aroused genitals of the preferred sex triggers action representations of sexual behavior. The neuronal response of the ventral striatum, centromedian thalamus and ventral premotor cortex to preferred sexual stimuli was consistent across all groups. We propose that this invariant response pattern in core regions of the human reward and motor system represents a functional endophenotype for sexual orientation independent of the gender of the observer and gender of the stimulus.


Asunto(s)
Conducta Sexual/fisiología , Adulto , Interpretación Estadística de Datos , Cara , Femenino , Genitales/fisiología , Gestos , Homosexualidad/fisiología , Homosexualidad/psicología , Humanos , Relaciones Interpersonales , Imagen por Resonancia Magnética , Masculino , Oxígeno/sangre , Fenotipo , Estimulación Luminosa , Recompensa
13.
J Neurooncol ; 67(1-2): 9-18, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15072443

RESUMEN

Vascular endothelial growth factor (VEGF) is one of the most important angiogenesis factors. In many tumors, VEGF plays a pivotal role for their vascularization and is necessary to supply the malignant tissue with oxygen and nutrients. However, VEGF receptors (VEGFR) have recently been detected also on some tumor cells, and autocrine mitogenic effects of VEGF have been suspected. Since glioma cells are known to produce large amounts of VEGF, we investigated VEGFR-expression and effects of VEGF on glioma cells. The three glioma cell lines and eight glioma cells cultivated from WHO grade IV gliomas investigated strongly expressed VEGF121 and VEGF165, but weakly either VEGFR-1 or -2, sometimes for both, as evidenced by reverse transcription-polymerase chain reaction (RT-PCR) and immunocytochemistry. Quantitative RT-PCR revealed a 1000- to 50-fold lower expression of VEGFR than in cultivated human umbilical vein endothelial cells. In two glioma cell lines analyzed, VEGF induced a weak tyrosine phosphorylation of the VEGFR, but downstream signal transduction effects on the mitogen-activated protein kinases p42/p44 or transcription factors like AP-1 or NFKB were within the background of the methods. In accordance, VEGF or the VEGFR agonists VEGF-D or placenta growth factor (P1GF) did not produce significant effects on glioma cell proliferation or VEGF production. We conclude that despite a low expression of VEGFR in some glioma cells functional effects are low and autocrine growth stimulatory effects within a glioma are minor.


Asunto(s)
Células Endoteliales/metabolismo , Glioma/metabolismo , Neovascularización Patológica/fisiopatología , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Inductores de la Angiogénesis/farmacología , Western Blotting , División Celular/efectos de los fármacos , Ensayo de Cambio de Movilidad Electroforética , Células Endoteliales/efectos de los fármacos , Ensayo de Inmunoadsorción Enzimática , Expresión Génica/efectos de los fármacos , Humanos , Inmunohistoquímica , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Receptores de Factores de Crecimiento Endotelial Vascular/biosíntesis , Receptores de Factores de Crecimiento Endotelial Vascular/efectos de los fármacos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/fisiología , Factores de Transcripción/metabolismo , Células Tumorales Cultivadas , Factor A de Crecimiento Endotelial Vascular/farmacología
14.
J Neurooncol ; 66(3): 341-4, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15015666

RESUMEN

We present a very rare case of an intracranial ganglioneurocytoma. This 57-year-old female patient noticed some concentration difficulties for about 5 months. Visual acuity was 80% on both sides. CT and MRI of her head demonstrated a 3 x 2.5 x 2.8 cm3 lesion within the third ventricle with inhomogenous enhancement of contrast medium. After a right pterional approach the tumor could be removed completely. Postoperatively there was a paresis of the oculomotor nerve on the right side and psychological changes. Histological examination revealed neuronal differentiation with neurocytes and small ganglionic cells and the tumor was graded as a ganglioneurocytoma (WHO grade II). Follow-up examination 6 months after the operation showed improvement of her third nerve paresis and of her neuropsychological deficits. MRI showed no recurrence.


Asunto(s)
Neoplasias del Ventrículo Cerebral/patología , Ganglioneuroma/patología , Tercer Ventrículo/patología , Biomarcadores de Tumor/análisis , Neoplasias del Ventrículo Cerebral/química , Neoplasias del Ventrículo Cerebral/cirugía , Femenino , Ganglioneuroma/química , Ganglioneuroma/cirugía , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Tercer Ventrículo/cirugía , Tomografía Computarizada por Rayos X
15.
J Neurooncol ; 63(2): 117-27, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12825816

RESUMEN

Gliomas are characterized by a deregulation of growth factor production and growth factor receptors expression, e.g. overproduction of the cytokine transforming growth factor-beta (TGF-beta) and overexpression/constitutive activation of receptors for the epidermal growth factor (EGF). Potential interactions of such growth factors and their signaling cascades could enhance the malignancy of these tumors. Therefore, we investigated the effects of TGF-beta and EGF alone and in combination on the proliferation of glioma cells cultivated from eight solid human WHO grade IV gliomas and one glioma cell line, analyzed the expression and intactness of the TGF-beta-signaling molecules Samd-4 and -2, and the phosphorylation of the EGF-signaling kinases ERK 1/2. The effects were divergent and complex: Whereas EGF mostly stimulated glioma cell proliferation, TGF-beta either enhanced, inhibited or had no significant effect on proliferation. In combination, co-stimulation and inhibition of the EGF-induced mitogenic activity could be observed. Smad-4/-2 were expressed in all glioma cells, one point mutation at base 1595 in Smad-4 did not affect its protein sequence. In part of the glioma cells, reduced phosphorylation of ERK 1/2 and expression of cyclin-dependent kinase inhibitor 1 or p21 was observed in co-stimulation experiments. These experiments show that TGF-beta can inhibit EGF-mediated effects only in some gliomas, whereas it enhances it in others. The interaction of both factors is very complex and varies between different gliomas.


Asunto(s)
Astrocitoma/metabolismo , Neoplasias Encefálicas/metabolismo , Factor de Crecimiento Epidérmico/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Astrocitoma/patología , Neoplasias Encefálicas/patología , Proteínas de Ciclo Celular/metabolismo , División Celular , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Inhibidor p27 de las Quinasas Dependientes de la Ciclina , Ciclinas/metabolismo , Cartilla de ADN/química , Receptores ErbB/metabolismo , Humanos , Técnicas para Inmunoenzimas , Antígeno Ki-67 , Sistema de Señalización de MAP Quinasas , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Fosforilación , Reacción en Cadena de la Polimerasa , Transducción de Señal , Células Tumorales Cultivadas , Proteínas Supresoras de Tumor/metabolismo
16.
Mov Disord ; 19(9): 1050-4, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15372594

RESUMEN

The optimal stimulation site in subthalamic deep brain stimulation (STN-DBS) was evaluated by correlation of the stereotactic position of the stimulation electrode with the electrophysiologically specified dorsal STN border. In a series of 25 electrodes, best clinical results with least energy consumption were found in contacts located in the dorsolateral border zone, whereas contacts within the subthalamic white matter, e.g., zona incerta, were significantly less effective. We suggest that the dorsolateral STN border should be covered by STN-DBS.


Asunto(s)
Terapia por Estimulación Eléctrica/instrumentación , Enfermedad de Parkinson/terapia , Núcleo Subtalámico/fisiología , Electrodos Implantados , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Enfermedad de Parkinson/patología , Estudios Retrospectivos , Sustancia Negra/patología , Núcleo Subtalámico/patología
17.
Ann Neurol ; 52(2): 240-3, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12210799

RESUMEN

Deep-brain stimulation of the subthalamic nucleus appears to reduce levodopa-induced dyskinesias, but whether this effect is caused by the reduction of the total levodopa ingestion or represents a direct effect on the motor system is unknown. Precision grip force of grasping movements and levodopa-induced dyskinesias was analyzed in 10 parkinsonian patients before and after 3 months of deep-brain stimulation of the subthalamic nucleus. Peak grip force was abnormally increased before surgery in the off-drug state and, particularly, in the on-drug state (sensitization). This grip force upregulation normalized with chronic deep-brain stimulation in both conditions (desensitization). Peak-dose dyskinesias also improved, and off-dystonia was completely abolished. Mean dosage of dopaminergic drugs was reduced, but force overflow and dyskinesias were equally improved in 2 patients without a reduction. Despite the same single levodopa test dose, force excess and levodopa-induced dyskinesias were drastically reduced after 3 months of deep-brain stimulation of the subthalamic nucleus. This indicates that direct effects of deep-brain stimulation of the subthalamic nucleus on levodopa-induced dyskinesias are likely to occur. Grip force overflow is a promising parameter to study the desensitizing effect of chronic deep-brain stimulation on levodopa-induced dyskinesias.


Asunto(s)
Discinesias/fisiopatología , Discinesias/terapia , Terapia por Estimulación Eléctrica , Fuerza de la Mano , Enfermedad de Parkinson/complicaciones , Núcleo Subtalámico/fisiopatología , Relación Dosis-Respuesta a Droga , Discinesias/etiología , Humanos , Levodopa/administración & dosificación , Levodopa/uso terapéutico , Valores de Referencia , Índice de Severidad de la Enfermedad , Factores de Tiempo
18.
Mov Disord ; 18(11): 1332-7, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14639676

RESUMEN

We studied 48 patients after bilateral subthalamic nucleus deep brain stimulation (STN-DBS) who were evaluated 6 months after the surgical procedure using the Unified Parkinson's Disease Rating Scale (UPDRS) in a standardized levodopa test. Additional follow-up was available in 32 patients after 12 months and in 20 patients after 24 months. At 6 months follow-up, STN-DBS reduced the UPDRS motor score by 50.9% compared to baseline. This improvement remained constant at 12 months with 57.5% and at 24 months with 57.3%. Relevant side effects after STN-DBS included intraoperative subdural hematoma without neurological sequelae (n = 1), minor intracerebral bleeding with slight transient hemiparesis (n = 1), dislocation of impulse generator (n = 2), transient perioperative confusional symptoms (n = 7), psychotic symptoms (n = 2), depression (n = 5), hypomanic behaviour (n = 2), and transient manic psychosis (n = 1). One patient died because of heart failure during the first postoperative year. The current series demonstrates efficacy and safety of STN-DBS beyond the first year after surgical procedure. Complications of STN-DBS comprise a wide range of psychiatric adverse events which, however, were temporary.


Asunto(s)
Enfermedad de Parkinson/terapia , Núcleo Subtalámico/fisiología , Estimulación Eléctrica/instrumentación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/diagnóstico , Índice de Severidad de la Enfermedad
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA