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1.
Nervenarzt ; 84(12): 1512-22, 2013 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-24253482

RESUMEN

The still continuing accelerated development of neurology in Germany is described in this article by a contemporary witness who was active in this field from 1965 to 2005. The personal experiences of the author are obviously only reflected over these 40 years so that the glorious antecedents in the period up to 1933, the era in which our predecessors were the world leaders in neurology, is not sufficiently covered. This dominance was lost by the anti-Semitism during the era of National Socialism and the sequelae of World War II. As a result of the war, German neurologists became effectively isolated and their participation in international congresses was forbidden so that a gradual reestablishment of alignment only became possible after 1960. In this brief description no attempt at completeness has been made and only subjectivity and brevity have been considered. An attempt is made to retrospectively convey what essentially happened. An exact dating of advances over the period was sometimes difficult. The readership will have the opportunity to share the surprise of the author on how meagre the neurological knowledge and diagnostic methods were 50 years ago, how rapidly the subsequent development happened, how rapidly things became obvious which 20 years ago nobody was aware of and despite the progress how pleased we were to find ourselves at the most recent state of error and probably still find ourselves nowadays. In particular, how powerless and untested the therapeutic efforts were at that time. The progress can only be measured by a comparison between then, 50 years ago and the present. A projection of the future based on these experiences is not attempted but it seems to be certain that many conceptions, diagnostic advances and therapy options are still undiscovered and that further exciting times can be expected.


Asunto(s)
Nacionalsocialismo/historia , Neurología/historia , Segunda Guerra Mundial , Predicción , Alemania , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Neurología/tendencias
2.
Science ; 178(4066): 1217-9, 1972 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-4637810

RESUMEN

When an observer views a wide-angled display rotating around his line of sight, he both feels his body tilted and sees a vertical straight edge tilted opposite to the moving stimulus. Displacement of the perceived vertical increases with stimulus speed to reach a maximum (averaging 15 degrees) at 30 degrees per second.


Asunto(s)
Percepción de Movimiento , Orientación , Humanos , Postura
3.
Science ; 225(4658): 208-12, 1984 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-6610216

RESUMEN

During the flight of Spacelab 1 the crew performed a number of experiments to explore changes in vestibular function and visual-vestibular interactions on exposure to microgravity. Measurements were made on the threshold for detection of linear oscillation, vestibulo-ocular reflexes elicited by angular and linear movements, oculomotor and posture responses to optokinetic stimulations, and responses to caloric stimulation. Tests were also conducted on the ground, during the 4 months before and on days 1 to 6 after flight. The most significant result was that caloric mystagmus of the same direction as on the earth could also be evoked in the weightless environment.


Asunto(s)
Aceleración , Pruebas Calóricas , Vuelo Espacial , Pruebas de Función Vestibular , Vestíbulo del Laberinto/fisiología , Percepción Visual/fisiología , Electrooculografía , Movimientos Oculares , Cabeza/fisiología , Humanos , Percepción de Movimiento/fisiología , Movimiento , Nistagmo Fisiológico , Ingravidez
6.
Cancer Res ; 61(6): 2744-50, 2001 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-11289157

RESUMEN

Human malignant gliomas are highly lethal neoplasms. Involved-field radiotherapy is the most important therapeutic measure. Most relapses originate from the close vicinity of the irradiated target field. Here, we report that sublethal doses of irradiation enhance the migration and invasiveness of human malignant glioma cells. This hitherto unknown biological effect of irradiation is p53 independent, involves enhanced alphavbeta3 integrin expression, an altered profile of matrix metalloproteinase-2 and matrix metalloproteinase-9 (MMP-2 and MMP-9) expression and activity, altered membrane type 1 MMP and tissue inhibitor of metalloproteinases-2 expression, and an altered BCL-2/BAX rheostat favoring resistance to apoptosis. BCL-2 gene transfer and irradiation cooperate to enhance migration and invasiveness in a synergistic manner. Sublethal irradiation of rat 9L glioma cells results in the formation of a greater number of tumor satellites in the rat brain in vivo concomitant with enhanced MMP-2 and reduced tissue inhibitor of metalloproteinases-2 expression. Collectively, these data suggest that the current concepts of involved-field radiotherapy for malignant glioma need to be reconsidered and that the pharmacological inhibition of migration and invasion during radiotherapy may represent a new therapeutic approach to improve the therapeutic efficacy of radiotherapy for malignant glioma.


Asunto(s)
Neoplasias Encefálicas/patología , Neoplasias Encefálicas/radioterapia , Movimiento Celular/efectos de la radiación , Glioblastoma/radioterapia , Glioma/patología , Células 3T3 , Animales , Neoplasias Encefálicas/metabolismo , Movimiento Celular/efectos de los fármacos , Glioblastoma/metabolismo , Glioblastoma/patología , Glioma/metabolismo , Humanos , Masculino , Metaloproteinasa 2 de la Matriz/biosíntesis , Metaloproteinasa 9 de la Matriz/biosíntesis , Ratones , Invasividad Neoplásica , Proteínas Proto-Oncogénicas c-bcl-2/biosíntesis , Tolerancia a Radiación/efectos de los fármacos , Ratas , Ratas Endogámicas F344 , Receptores de Vitronectina/antagonistas & inhibidores , Esferoides Celulares/patología , Esferoides Celulares/efectos de la radiación , Células Tumorales Cultivadas/efectos de la radiación
7.
Oncogene ; 19(19): 2338-45, 2000 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-10822385

RESUMEN

CD95L-induced apoptosis involves caspase activation and is facilitated when RNA and protein synthesis are inhibited. Here, we report that hyperthermia sensitizes malignant glioma cells to CD95L- and APO2L-induced apoptosis in the absence, but not in the presence, of inhibitors of RNA and protein synthesis. Hyperthermia does not alter CD95 expression at the cell surface and does not modulate the morphology of CD95-mediated cell death on electron microscopy. Bcl-2 gene transfer inhibits apoptosis and abrogates the sensitization mediated by hyperthermia. Hyperthermia does not overcome resistance to apoptosis conferred by the viral caspase inhibitor, crm-A, indicating the absolute requirement for the activation of crm-A-sensitive caspases, probably caspase 8, for apoptosis. CD95L-evoked DEVD-amc-cleaving caspase activity is enhanced by hyperthermia, suggesting that hyperthermia operates upstream of caspase processing to promote apoptosis. There is no uniformly enhanced processing of three caspase 3 substrates, poly-ADP ribose polymerase (PARP), protein kinase C (PKC) delta and DNA fragmentation factor (DFF) 45. Yet, hyperthermia promotes CD95L-evoked DNA fragmentation. Interestingly, hyperthermia enhances the CD95L-evoked release of cytochrome c in the absence, but not in the presence, of CHX. In contrast, the reduction of the mitochondrial membrane potential is enhanced by hyperthermia both in the absence and presence of CHX, and enhanced cytochrome c release is not associated with significantly enhanced caspase 9 processing. The potentiation of cytochrome c release at hyperthermic conditions in the absence of CHX is abrogated by Bcl-2. Thus, either hyperthermia or inhibition of protein synthesis by CHX potentiate cytotoxic cytokine-induced apoptosis. These pathways show no synergy, but rather redundance, indicating that CHX may function to promote apoptosis in response to cytotoxic cytokines by inhibiting the synthesis of specific proteins whose synthesis, function or degradation is temperature-sensitive.


Asunto(s)
Apoptosis/fisiología , Grupo Citocromo c/metabolismo , Glioma/metabolismo , Hipertermia Inducida , Glicoproteínas de Membrana/metabolismo , Proteínas Virales , Proteínas Reguladoras de la Apoptosis , Caspasa 8 , Caspasa 9 , Inhibidores de Caspasas , Caspasas/metabolismo , Cumarinas/metabolismo , Cicloheximida/farmacología , Proteína Ligando Fas , Glioma/patología , Glioma/terapia , Humanos , Isoenzimas/efectos de los fármacos , Isoenzimas/metabolismo , Glicoproteínas de Membrana/farmacología , Potenciales de la Membrana/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/efectos de los fármacos , Oligopéptidos/metabolismo , Poli(ADP-Ribosa) Polimerasas/metabolismo , Proteína Quinasa C/efectos de los fármacos , Proteína Quinasa C/metabolismo , Proteína Quinasa C-delta , Inhibidores de la Síntesis de la Proteína/farmacología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Serpinas/metabolismo , Transducción de Señal , Ligando Inductor de Apoptosis Relacionado con TNF , Células Tumorales Cultivadas , Factor de Necrosis Tumoral alfa/metabolismo
8.
Oncogene ; 17(18): 2323-32, 1998 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-9811463

RESUMEN

Nitric oxide (NO) is thought to play an important role in neurotransmission, inflammation, and regulation of cell death in the mammalian brain. Here, we examined the synthesis and biological effects of NO in human malignant glioma cells. Exposure to cytokines such as interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha or interleukin (IL)-1beta and lipopolysaccharide (LPS) induced NO synthesis in rat C6 and A172 human glioma cells, but not in LN-229, T98G or LN-18 human malignant glioma cells. Induced release of NO involved enhanced expression of inducible NO synthase (iNOS). Failure to detect NO release in the latter cell lines was not overcome by neutralization of endogenous TGF-beta or by coexposure to cytokines, LPS, and antioxidants. Apoptosis induced by CD95 ligand (CD95L) did not involve NO formation. Neither NOS inhibitors nor NO donators modulated CD95L-induced apoptosis. Dexamethasone (DEX)-mediated protection of glioma cells from CD95L-induced apoptosis was also independent of DEX effects on NO metabolism. DEX inhibited not only cytokine/LPS-evoked NO release but also attenuated the toxicity of NO in three of five cell lines. Forced expression of temperature-sensitive p53 val135 in C6 cells in either mutant or wild-type conformation inhibited cytokine/LPS-induced NO synthesis. Further, accumulation of p53 in both mutant or wild-type conformation protected glioma cells from the toxicity of exogenous NO, consistent with a gain of p53 function associated with p53 accumulation. We conclude that resistance to NO-dependent immune defense mechanisms may contribute to the malignant progression of human cancers with p53 alterations, notably those associated with the accumulation of mutant p53 protein.


Asunto(s)
Apoptosis , Citocinas/farmacología , Genes p53/fisiología , Glioma/metabolismo , Proteínas de Neoplasias/biosíntesis , Óxido Nítrico Sintasa/biosíntesis , Óxido Nítrico/biosíntesis , Proteína p53 Supresora de Tumor/metabolismo , Animales , Antineoplásicos Hormonales/farmacología , Cicloheximida/farmacología , Dexametasona/farmacología , Genes p53/genética , Glioma/genética , Glioma/patología , Humanos , Interleucina-1/farmacología , Lipopolisacáridos/farmacología , Óxido Nítrico/farmacología , Óxido Nítrico Sintasa/antagonistas & inhibidores , Óxido Nítrico Sintasa de Tipo II , Inhibidores de la Síntesis de la Proteína/farmacología , Ratas , Factor de Crecimiento Transformador alfa/farmacología , Factor de Crecimiento Transformador beta/farmacología , Células Tumorales Cultivadas , Receptor fas/fisiología
9.
Oncogene ; 19(37): 4210-20, 2000 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-10980594

RESUMEN

Cellular resistance to multiple proapoptotic stimuli and invasion of surrounding brain tissue by migrating tumor cells are main obstacles to an effective therapy for human malignant glioma. Here, we report that the Wnt family of embryonic differentiation genes modulate growth of malignant glioma cells in vitro and in vivo and inhibit cellular migration in vitro. sFRPs (soluble Frizzled-related proteins) are soluble proteins that bind to Wnt and interfere with Wnt signaling. We find that sFRP-1 and sFRP-2 are produced by the majority of longterm and ex vivo malignant glioma cell lines. Glioma cells that ectopically express sFRPs exhibit increased clonogenicity and enhanced resistance to serum starvation. In contrast, sFRPs do not modulate glioma cell susceptibility to apoptosis induced by the cytotoxic cytokines, CD95 (Fas/APO-1) ligand (CD95L) or Apo2 ligand/tumor necrosis factor-related apoptosis-inducing ligand (Apo2L/TRAIL), or various cytotoxic drugs. sFRP-2 strongly promotes the growth of intracranial glioma xenografts in nude mice. In contrast, enhanced expression of sFRPs inhibits the motility of glioma cells in vitro. sFRP-mediated effects on glioma cells are accompanied by decreased expression and activity of matrix metalloproteinase-2 (MMP-2) and decreased tyrosine phosphorylation of beta-catenin. Thus, sFRPs promote survival under non-supportive conditions and inhibit the migration of glioma cells. We suggest that the regulation of these cellular processes involves expression of MMP-2 and tyrosine phosphorylation of beta-catenin. These data support a function for Wnt signaling and its modulation by sFRPs in the biology of human gliomas. Oncogene (2000) 19, 4210 - 4220


Asunto(s)
Neoplasias Encefálicas/patología , Glioblastoma/patología , Proteínas de la Membrana , Proteínas de Neoplasias/fisiología , Proteínas/fisiología , Transactivadores , Proteínas de Pez Cebra , Animales , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Neoplasias Encefálicas/genética , División Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Supervivencia Celular , Células Clonales/patología , Medio de Cultivo Libre de Suero , Proteínas del Citoesqueleto/metabolismo , Glioblastoma/metabolismo , Humanos , Péptidos y Proteínas de Señalización Intracelular , Metaloproteinasa 2 de la Matriz/fisiología , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Fosforilación , Procesamiento Proteico-Postraduccional , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/fisiología , Trasplante Heterólogo , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/metabolismo , Células Tumorales Cultivadas/trasplante , Proteínas Wnt , beta Catenina
10.
J Neurosci ; 20(24): 9126-34, 2000 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-11124990

RESUMEN

1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) produces clinical, biochemical, and neuropathological changes reminiscent of those occurring in idiopathic Parkinson's disease (PD). Here we show that a peptide caspase inhibitor, N-benzyloxy-carbonyl-val-ala-asp-fluoromethyl ketone, or adenoviral gene transfer (AdV) of a protein caspase inhibitor, X-chromosome-linked inhibitor of apoptosis (XIAP), prevent cell death of dopaminergic substantia nigra pars compacta (SNpc) neurons induced by MPTP or its active metabolite 1-methyl-4-phenylpyridinium in vitro and in vivo. Because the MPTP-induced decrease in striatal concentrations of dopamine and its metabolites does not differ between AdV-XIAP- and control vector-treated mice, this protection is not associated with a preservation of nigrostriatal terminals. In contrast, the combination of adenoviral gene transfer of XIAP and of the glial cell line-derived neurotrophic factor to the striatum provides synergistic effects, rescuing dopaminergic SNpc neurons from cell death and maintaining their nigrostriatal terminals. These data suggest that a combination of a caspase inhibitor, which blocks death, and a neurotrophic factor, which promotes the specific function of the rescued neurons, may be a promising strategy for the treatment of PD.


Asunto(s)
Adenoviridae/genética , Terapia Genética/métodos , Factores de Crecimiento Nervioso , Proteínas del Tejido Nervioso/genética , Enfermedad de Parkinson Secundaria/terapia , Proteínas/genética , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina , Animales , Apoptosis/efectos de los fármacos , Inhibidores de Caspasas , Células Cultivadas , Dopamina/metabolismo , Sinergismo Farmacológico , Inhibidores Enzimáticos/farmacología , Técnicas de Transferencia de Gen , Vectores Genéticos/genética , Vectores Genéticos/farmacología , Factor Neurotrófico Derivado de la Línea Celular Glial , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas del Tejido Nervioso/metabolismo , Proteínas del Tejido Nervioso/farmacología , Enfermedad de Parkinson Secundaria/inducido químicamente , Enfermedad de Parkinson Secundaria/metabolismo , Terminales Presinápticos/efectos de los fármacos , Terminales Presinápticos/metabolismo , Proteínas/metabolismo , Proteínas/farmacología , Ratas , Ratas Sprague-Dawley , Sustancia Negra/efectos de los fármacos , Sustancia Negra/metabolismo , Sustancia Negra/patología , Proteína Inhibidora de la Apoptosis Ligada a X
11.
Cell Death Differ ; 5(1): 29-37, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10200443

RESUMEN

Fas/CD95/Apo-I has been shown to stimulate a variety of molecules including several members of the caspase family and the acidic sphingomyelinase (Martin and Green 1995; Gulbins et al, 1995). Here, we demonstrate that Fas receptor-triggered activation of the acidic sphingomyelinase, consumption of sphingomyelin, release of ceramide, and subsequent activation of JNK and p38-K are regulated by caspases. Inhibition of caspases by Ac-YVAD-chloromethylketone or transient CrmA transfection prevented stimulation of acidic sphingomyelinase, release of ceramide and activation of JNK and p38-K upon Fas-receptor crosslinking. Likewise, Fas triggered apoptosis was almost completely blocked by Ac-YVAD-chloromethylketone or CrmA mediated inhibition of caspases. The results suggest a new signalling cascade from the Fas receptor via caspases to acidic sphingomyelinase, ceramide and JNK/p38-K.


Asunto(s)
Apoptosis/fisiología , Caspasas/metabolismo , Células Jurkat/citología , Proteínas Quinasas Activadas por Mitógenos , Esfingomielina Fosfodiesterasa/metabolismo , Proteínas Virales , Receptor fas/metabolismo , Ácidos/metabolismo , Inhibidores de Captación Adrenérgica/farmacología , Clorometilcetonas de Aminoácidos/farmacología , Apoptosis/efectos de los fármacos , Proteínas Quinasas Dependientes de Calcio-Calmodulina/metabolismo , Ceramidas/metabolismo , Inhibidores de Cisteína Proteinasa/genética , Inhibidores de Cisteína Proteinasa/farmacología , Diglicéridos/metabolismo , Regulación Enzimológica de la Expresión Génica , Humanos , Imipramina/farmacología , Células Jurkat/enzimología , Serpinas/genética , Transducción de Señal/fisiología , Linfocitos T/citología , Linfocitos T/enzimología , Transfección , Proteínas Quinasas p38 Activadas por Mitógenos
12.
Cell Death Differ ; 5(10): 847-57, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10203688

RESUMEN

In rats, striatal histotoxic hypoxic lesions produced by the mitochondrial toxin malonate resemble those of focal cerebral ischemia. Intrastriatal injections of malonate induced cleavage of caspase-2 beginning at 6 h, and caspase-3-like activity as identified by DEVD biotin affinity-labeling within 12 h. DEVD affinity-labeling was prevented and lesion volume reduced in transgenic mice overexpressing BCL-2 in neuronal cells. Intrastriatal injection of the tripeptide, N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (zVAD-fmk), a caspase inhibitor, at 3 h, 6 h, or 9 h after malonate injections reduced the lesion volume produced by malonate. A combination of pretreatment with the NMDA antagonist, dizocilpine (MK-801), and delayed treatment with zVAD-fmk provided synergistic protection compared with either treatment alone and extended the therapeutic window for caspase inhibition to 12 h. Treatment with cycloheximide and zVAD-fmk, but not with MK-801, blocked the malonate-induced cleavage of caspase-2. NMDA injections alone resulted in a weak caspase-2 cleavage. These results suggest that malonate toxicity induces neuronal death by more than one pathway. They strongly implicate early excitotoxicity and delayed caspase activation in neuronal loss after focal ischemic lesions and offer a new strategy for the treatment of stroke.


Asunto(s)
Clorometilcetonas de Aminoácidos/farmacología , Encéfalo/patología , Inhibidores de Caspasas , Cuerpo Estriado/efectos de los fármacos , Maleato de Dizocilpina/farmacología , Genes bcl-2 , Hipoxia Encefálica/prevención & control , Fármacos Neuroprotectores/farmacología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Clorometilcetonas de Aminoácidos/uso terapéutico , Animales , Apoptosis , Encéfalo/efectos de los fármacos , Caspasa 2 , Caspasa 3 , Caspasas/metabolismo , Cuerpo Estriado/patología , Cuerpo Estriado/fisiología , Cicloheximida/farmacología , Inhibidores de Cisteína Proteinasa/farmacología , Inhibidores de Cisteína Proteinasa/uso terapéutico , Maleato de Dizocilpina/uso terapéutico , Sinergismo Farmacológico , Humanos , Hipoxia Encefálica/inducido químicamente , Hipoxia Encefálica/patología , Etiquetado Corte-Fin in Situ , Masculino , Malonatos/toxicidad , Ratones , Ratones Transgénicos , Fármacos Neuroprotectores/uso terapéutico , Proteínas Proto-Oncogénicas c-bcl-2/genética , Ratas , Ratas Sprague-Dawley
13.
J Neurol ; 252(3): 291-9, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16189725

RESUMEN

Adult medulloblastoma is a rare tumor with few retrospective studies published so far. The role of adjuvant chemotherapy or chemotherapy at relapse is unclear. This study reports therapy and outcome in all adult (>or=16 years old) medulloblastoma (n=34) and supratentorial primitive neuroectodermal tumor (PNET) patients (n=2) treated in 2 neuro-oncological centers between 1976 and 2002. The median age was 24.5 years (range 16-76). After resection, 16 patients were treated with craniospinal radiotherapy alone, 20 patients also received adjuvant chemotherapy (8 vincristine, CCNU, cisplatin; 7 methotrexate alone or methotrexate/vincristine-based polychemotherapy; 5 other protocols). Median survival in the whole cohort was 126 months (2+ - 200+months). Five-year and 10-year survival rates were 79 % and 56%. Adjuvant chemotherapy was associated with a non-significant trend to prolonged survival (relative risk (RR) 1.89; p=0.068). The median progression-free survival (PFS) after primary therapy was 83 months. At relapse, 10 of 12 evaluable patients achieved a complete response upon second-line therapy. The median survival times from first (n=17) and second relapse (n=9) were 21 months (0-67+ months; 5/17 without second relapse) and 20 months (1-29 months). Cox regression analysis revealed the infiltration of the floor of the 4(th) ventricle at diagnosis as the only therapy-independent prognostic factor (RR 0.48; p=0.03). In conclusion, adjuvant chemotherapy may prolong survival in adult medulloblastoma patients. Moreover, second-line therapy may be beneficial for these patients. As in pediatric medulloblastoma patients, primary infiltration of the floor of the 4(th) ventricle indicates a poor prognosis.


Asunto(s)
Neoplasias Cerebelosas/terapia , Meduloblastoma/terapia , Adolescente , Adulto , Anciano , Análisis de Varianza , Neoplasias Cerebelosas/diagnóstico , Neoplasias Cerebelosas/epidemiología , Neoplasias Cerebelosas/patología , Terapia Combinada , Demografía , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Relación Dosis-Respuesta en la Radiación , Quimioterapia/métodos , Femenino , Humanos , Masculino , Meduloblastoma/diagnóstico , Meduloblastoma/epidemiología , Meduloblastoma/patología , Persona de Mediana Edad , Radioterapia de Alta Energía/métodos , Recurrencia , Análisis de Regresión , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
14.
Leukemia ; 11(11): 1842-9, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9369416

RESUMEN

A gene encoding the p53 val135 mutant, which assumes mutant conformation at 38.5 degrees C and wild-type conformation at 32.5 degrees C, was introduced into p53-deficient K562 myeloid leukemia cells. Forced expression of wild-type, but not mutant, p53 resulted in growth arrest, accumulation of p21 and Bax proteins, and delayed cell death. Wild-type p53 enhanced the cytotoxic effects of some drugs and attenuated those of others. Compared with wild-type p53, mutant p53 induced much stronger sensitization to drug cytotoxicity. This occurred in the absence of effects on cell cycle progression or activation of several p53 target genes. Although both mutant and wild-type p53 induced changes of immunophenotype, no specific pattern of differentiation was associated with enhanced chemosensitivity. Thus, (1) induction of growth arrest and activation of p53 target genes such as p21 and bax are linked to the wild-type conformation of p53; (2) p53 induces immunophenotypic changes of myeloid leukemia cells suggestive of multidirectional differentiation in a conformation-dependent manner; and (3) (so-called) mutant p53 induces chemosensitization in the absence of effects on cell cycle progression, activation of bax, p21, gadd45 and mdm-2, or a specific pattern of differentiation; and (4) chemosensitization mediated by wild-type p53 may be masked by transcription-dependent induction of growth arrest.


Asunto(s)
Antineoplásicos/farmacología , Leucemia Mieloide/metabolismo , Proteína p53 Supresora de Tumor/fisiología , Animales , Ciclo Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Resistencia a Antineoplásicos , Citometría de Flujo , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Leucemia Mieloide/patología , Leucemia Mieloide/fisiopatología , Ratones , Microscopía Electrónica , Mutación , Temperatura , Transfección , Células Tumorales Cultivadas/ultraestructura , Proteína p53 Supresora de Tumor/genética
15.
Clin Neurol Neurosurg ; 107(5): 432-8, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16023542

RESUMEN

Toxocariasis is a worldwide-occurring parasitic infection leading to tissue damage in various organs due to wandering Toxocara larvae (visceral larva migrans). More than 40 cases of CNS involvement in children and immunocompetent adults have been documented in detail to date. Here, we present evidence of eosinophilic meningomyelitis in an adult without known risk factors and with positive Toxocara antibody response in CSF, but not in blood. Toxocariasis has to remain among the differential diagnosis in patients with eosinophilic CNS infection even if serological tests in blood are negative. Adult cases seem to be more frequent than previously thought (about 60%).


Asunto(s)
Eosinofilia/parasitología , Meningitis/parasitología , Mielitis/parasitología , Toxocara canis , Toxocariasis/diagnóstico , Adulto , Animales , Anticuerpos Antihelmínticos/líquido cefalorraquídeo , Eosinofilia/líquido cefalorraquídeo , Humanos , Meningitis/líquido cefalorraquídeo , Mielitis/líquido cefalorraquídeo , Toxocara canis/inmunología
16.
Brain Pathol ; 8(2): 285-93, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9546287

RESUMEN

CD95 (Fas/APO-1) and its ligand (CD95L) belong to a growing cytokine and cytokine receptor family that includes nerve growth factor (NGF) and tumor necrosis factor (TNF) and their corresponding receptors. CD95 expression increases during malignant progression from low-grade to anaplastic astrocytoma and is most prominent in perinecrotic areas of glioblastoma. There is, however, no evidence that CD95 expression in malignant gliomas is triggered by hypoxia or ischemia. Agonistic antibodies to CD95, or the natural ligand, CD95L, induce apoptosis in human malignant glioma cells in vitro. Glioma cell sensitivity to CD95-mediated apoptosis is regulated by CD95 expression at the cell surface and by the levels of intracellular apoptosis-regulatory proteins, including bcl-2 family members. Several cytotoxic drugs synergize with CD95L to kill glioma cells. For as yet unknown reasons, glioma cells may co-express CD95 and CD95L in vitro without undergoing suicide or fratricide. Yet, they kill T cells via CD95/CD95L interactions and are sensitive to exogenously added CD95L. Since CD95L is expressed in gliomas in vivo, too, forced induction of CD95 expression might promote therapeutic apoptosis in these tumors. That glioma cells differ from nontransformed T cells in their sensitivity to CD95 antibodies or recombinant ligand, may allow the development of selective CD95 agonists with high antitumor activity that spare normal brain tissue. A family of death ligand/receptor pairs related to CD95L/CD95, including APO2L (TRAIL) and its multiple receptors is beginning to emerge. Although several issues regarding glioma cell sensitivity to CD95L/CD95-mediated apoptosis await elucidation, CD95 is a promising target for the treatment of malignant glioma.


Asunto(s)
Neoplasias Encefálicas/tratamiento farmacológico , Glioma/tratamiento farmacológico , Glicoproteínas de Membrana/uso terapéutico , Animales , Antineoplásicos/uso terapéutico , Neoplasias Encefálicas/metabolismo , Membrana Celular/metabolismo , Sinergismo Farmacológico , Proteína Ligando Fas , Glioma/metabolismo , Humanos , Glicoproteínas de Membrana/efectos adversos , Glicoproteínas de Membrana/metabolismo , Proteínas Recombinantes , Receptor fas/metabolismo
17.
Brain Pathol ; 13(3): 421-3, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12946033

RESUMEN

The March COM. A 41-year-old woman presented in 1997 with diffuse abdominal pain, meteorism and intermittent diarrhea. Imaging studies revealed a focal rounded lesion in the liver. Although there was no history of progesterone or estrogen therapy, the radiographic appearance was considered to be suggestive of adenoma. The lesion was monitored by ultrasound until October 2000 when a resection was performed because of the presumed risk of a malignant transformation. H&E stained sections revealed an ectopic ependymoma that was strongly positive for GFAP. The surrounding hepatic tissue was negative for GFAP. An extensive search for a CNS manifestation or any other extraspinal localization was unrevealing. We believe we have encountered the first case of an ectopic ependymoma presenting as a solitary hepatic lesion in the absence of CNS disease. Ependymomas generally arise in the CNS in relation to the ventricular system. Extraneural metastasis from ependymomas may occasionally occur even years after detection and treatment of the primary lesion and have been the subject of several reports. In contrast, there are only anecdotal reports of primary extraneural "ectopic" ependymomas. So far those rare cases have only been found in close vicinity to the neural axis, eg, in the sacrococcygeal region, the posterior mediastinum or the ovaries and are there thought to originate from embryonic remnant cells around the neural tube. Distant metastases of ependymomas invading or arising within the extraneural lumbosacral soft tissue may occur in this situation. Here, we report what appears to be the first case of a primary ectopic ependymoma originating in the liver, with no signs of CNS or other systemic involvement.


Asunto(s)
Neoplasias del Sistema Nervioso Central/patología , Ependimoma/patología , Hígado/patología , Dolor Abdominal , Adenoma/diagnóstico , Adulto , Neoplasias del Sistema Nervioso Central/metabolismo , Ependimoma/metabolismo , Femenino , Proteína Ácida Fibrilar de la Glía/metabolismo , Humanos , Hígado/lesiones , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos X
18.
Brain Pathol ; 10(2): 223-34, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10764042

RESUMEN

Bag-1 is a heat shock 70 kDa (Hsp70)-binding protein that can collaborate with Bcl-2 in suppressing apoptosis under some conditions. Here, we report that 11 of 12 human glioma cell lines express Bag-1 protein in vitro. Moreover, 15 of 19 human glioblastomas expressed Bag-1 as assessed by immunohistochemistry in primary tumor specimens. To examine the biological effects of Bag-1 in glioma cells, we expressed Bag-1 or Bcl-2 transgenes in 2 human malignant glioma cell lines, LN-18 and LN-229. Bag-1 significantly slowed glioma cell growth and reduced clonogenicity of both cell lines in vitro. Coexpressed Bcl-2 abrogated these effects of Bag-1. Intracranial LN-229 glioma xenografts implanted into nude mice revealed a substantial growth advantage afforded by Bcl-2. Bag-1 had no such effect, either in the absence or presence of Bcl-2. Upon serum starvation in vitro, Bcl-2 prevented cell death whereas Bag-1 did not. Both Bcl-2 and Bag-1 slowed proliferation of serum-starved cells when expressed alone. Importantly, coexpression of Bcl-2 and Bag-1 provided a distinct growth advantage under conditions of serum starvation that is probably the result of (i) the death-preventing activity of Bcl-2 and (ii) the property of Bag-1 to overcome a Bcl-2-mediated enhancement of exit from the cell cycle. In contrast to these Bcl-2/Bag-1 interactions observed under serum starvation conditions, Bag-1 did not further enhance the strong protection from staurosporine-, CD95 (Fas/Apo1) ligand-, Apo2 ligand (TRAIL)- or chemotherapeutic drug-induced apoptosis afforded by Bcl-2. Taken together, these results indicate a role for Bag-1/Bcl-2 interactions in providing a survival advantage to cancer cells in a deprived microenvironment that may be characteristic of ischemic/hypoxic tumors such as human glioblastoma multiforme, and suggest that Bcl-2/Bag-1 interactions also modulate cell proliferation.


Asunto(s)
Proteínas Portadoras/fisiología , Glioma/patología , Glioma/fisiopatología , Proteínas Proto-Oncogénicas c-bcl-2/fisiología , Animales , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Proteínas Portadoras/genética , Proteínas Portadoras/farmacología , Ciclo Celular/efectos de los fármacos , Ciclo Celular/fisiología , División Celular/fisiología , Supervivencia Celular/efectos de los fármacos , Medio de Cultivo Libre de Suero , Proteínas de Unión al ADN , Sinergismo Farmacológico , Glioma/metabolismo , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/farmacología , Factores de Transcripción , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/patología
19.
FEBS Lett ; 409(1): 17-23, 1997 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-9199495

RESUMEN

CD95 ligand is a cytotoxic cytokine that induces apoptosis. Here we report that CD95-mediated apoptosis of human malignant glioma cells is associated with arachidonic acid (AA) release. Inhibitors of phospholipase A2, phospholipase C or diacylglycerol lipase have minor effects on AA release and fail to modulate apoptosis. Formation of two AA metabolites generated during CD95-dependent apoptosis is attenuated by the lipoxygenase inhibitor, nordihydroguaretic acid (NDGA). NDGA also blocks CD95 ligand-induced apoptosis. This effect is independent of antioxidant properties of NDGA. Lipoxygenase may thus play a critical role in CD95 ligand-induced apoptosis of human malignant glioma cells.


Asunto(s)
Apoptosis/efectos de los fármacos , Apoptosis/inmunología , Glioma/terapia , Inhibidores de la Lipooxigenasa/farmacología , Glicoproteínas de Membrana/fisiología , Receptor fas/metabolismo , Animales , Ácido Araquidónico/metabolismo , Proteína Ligando Fas , Glioma/inmunología , Glioma/metabolismo , Humanos , Ligandos , Masoprocol/farmacología , Ratones , Fosfolipasas/antagonistas & inhibidores , Células Tumorales Cultivadas
20.
FEBS Lett ; 440(3): 419-24, 1998 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-9872414

RESUMEN

Malignant progression in gliomas is correlated with increased migratory capacity which involves metalloproteolytic activity. Here, we report that ectopic expression of BCL-2 in two malignant glioma sublines markedly promoted glioma cell migration from spheroids and invasion into Matrigel-coated membranes. Invasion of fetal rat-brain aggregates was enhanced by BCL-2. Zymography revealed activation of matrix metalloproteinase-2 (MMP-2) in BCL-2-expressing cells. BCL-2 expressing cells showed an increase in MMP-2/-3/-12 (LN-18), and MMP-9/-12 and cell surface urokinase-type plasminogen activator (u-PA) (LN-229) mRNA and a reduction in tissue inhibitors of metalloproteinases (TIMP)-2 mRNA (LN-229). Taken together, we propose a novel function for BCL-2 in the malignant phenotype of glioma cells, that is, to enhance migration and invasion by altering the expression of a set of metalloproteinases and their inhibitors.


Asunto(s)
Glioma/patología , Invasividad Neoplásica , Proteínas Proto-Oncogénicas c-bcl-2/fisiología , Animales , Neoplasias Encefálicas/secundario , Movimiento Celular , Regulación hacia Abajo , Gelatinasas/metabolismo , Técnicas de Transferencia de Gen , Humanos , Metaloproteinasa 2 de la Matriz , Metaloendopeptidasas/metabolismo , Fenotipo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Ratas , Esferoides Celulares/patología , Inhibidor Tisular de Metaloproteinasa-2/metabolismo , Células Tumorales Cultivadas , Regulación hacia Arriba , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo
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