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1.
J Musculoskelet Neuronal Interact ; 16(3): 183-92, 2016 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-27609033

RESUMEN

OBJECTIVES: to investigate feasibility, safety and efficacy of home-based side-alternating whole body vibration (sWBV) to improve motor function in toddlers with cerebral palsy (CP). METHODS: Randomized controlled trial including 24 toddlers with CP (mean age 19 months (SD±3.1); 13 boys). INTERVENTION: 14 weeks sWBV with ten 9-minute sessions weekly (non-individualized). Group A started with sWBV, followed by 14 weeks without; in group B this order was reversed. Feasibility (≥70% adherence) and adverse events were recorded; efficacy evaluated with the Gross Motor Function Measure (GMFM-66), Pediatric Evaluation of Disability Inventory (PEDI), at baseline (T0), 14 (T1) and 28 weeks (T2). RESULTS: Developmental change between T0 and T1 was similar in both groups; change scores in group A and B: GMFM-66 2.4 (SD±2.1) and 3.3 (SD±2.9) (p=0.412); PEDI mobility 8.4 (SD±6.6) and 3.5 (SD±9.2) (p=0.148), respectively. In two children muscle tone increased post-sWBV. 24 children received between 67 and 140 sWBV sessions, rate of completed sessions ranged from 48 to 100% and no dropouts were observed. CONCLUSION: A 14-week home-based sWBV intervention was feasible and safe in toddlers with CP, but was not associated with improvement in gross motor function.


Asunto(s)
Parálisis Cerebral/rehabilitación , Modalidades de Fisioterapia , Vibración/uso terapéutico , Preescolar , Femenino , Humanos , Lactante , Masculino , Modalidades de Fisioterapia/instrumentación , Proyectos Piloto , Vibración/efectos adversos
2.
Eur J Paediatr Neurol ; 20(1): 147-51, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26387070

RESUMEN

OBJECTIVE: Mutations in the CDKL5 gene cause an early-onset epileptic encephalopathy. To date, little is known about effective antiepileptic treatment in this disorder. METHOD: Accordingly, the aim of this retrospective study was to explore the role of different antiepileptic drugs (AEDs) and the ketogenic diet (KD) in the treatment of this rare genetic disorder. We evaluated the efficacy in 39 patients with CDKL5 mutations at 3, 6 and 12 months after the introduction of each treatment. One patient was lost to follow-up after 6 and 12 months. RESULTS: The responder rate (>50% reduction in seizure frequency) to at least one AED or KD was 69% (27/39) after 3 months, 45% (17/38) after 6 months and 24% (9/38) after 12 months. The highest rate of seizure reduction after 3 months was reported for FBM (3/3), VGB (8/25), CLB (4/17), VPA (7/34), steroids (5/26), LTG (5/23) and ZNS (2/11). Twelve patients (31%) experienced a seizure aggravation to at least one AED. Most patients showed some but only initial response to various AEDs with different modes of actions. SIGNIFICANCE: Considering both age-related and spontaneous fluctuation in seizure frequency and the unknown impact of many AEDs or KD on cognition, our data may help defining realistic treatment goals and avoiding overtreatment in patients with CDKL5 mutations. There is a strong need to develop new treatment strategies for patients with this rare mutation.


Asunto(s)
Anticonvulsivantes/uso terapéutico , Dieta Cetogénica , Epilepsia/dietoterapia , Epilepsia/tratamiento farmacológico , Adulto , Epilepsia/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación , Proteínas Serina-Treonina Quinasas/genética , Estudios Retrospectivos , Convulsiones/prevención & control , Resultado del Tratamiento , Adulto Joven
3.
Oncogene ; 34(18): 2325-36, 2015 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-24954505

RESUMEN

Disease progression and recurrence are major barriers to survival for breast cancer patients. Understanding the etiology of recurrent or metastatic breast cancer and underlying mechanisms is critical for the development of new treatments and improved survival. Here, we report that two commonly overexpressed breast cancer oncogenes, Ron (Recepteur d'Origine Nantaise) and DEK, cooperate to promote advanced disease through multipronged effects on ß-catenin signaling. The Ron receptor is commonly activated in breast cancers, and Ron overexpression in human disease stimulates ß-catenin nuclear translocation and is an independent predictor of metastatic dissemination. Dek is a chromatin-associated oncogene whose expression has been linked to cancer through multiple mechanisms, including ß-catenin activity. We demonstrate here that Dek is a downstream target of Ron receptor activation in murine and human models. The absence of Dek in the MMTV-Ron mouse model led to a significant delay in tumor development, characterized by decreased cell proliferation, diminished metastasis and fewer cells expressing mammary cancer stem cell markers. Dek complementation of cell lines established from this model was sufficient to promote cellular growth and invasion. Mechanistically, Dek expression stimulated the production and secretion of Wnt ligands to sustain an autocrine/paracrine canonical ß-catenin signaling loop. Finally, we show that Dek overexpression promotes tumorigenic phenotypes in immortalized human mammary epithelial MCF10A cells and, in the context of Ron receptor activation, correlates with disease recurrence and metastasis in patients. Overall, our studies demonstrate that DEK overexpression, due in part to Ron receptor activation, drives breast cancer progression through the induction of Wnt/ß-catenin signaling.


Asunto(s)
Neoplasias de la Mama/patología , Proteínas Cromosómicas no Histona/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas Oncogénicas/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Vía de Señalización Wnt , Animales , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Proliferación Celular , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Neoplasias Experimentales , Proteínas de Unión a Poli-ADP-Ribosa
4.
Oncogene ; 33(11): 1429-37, 2014 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-23542172

RESUMEN

Multiple growth pathways lead to enhanced proliferation in malignant cells. However, how the core machinery of DNA replication is regulated by growth signaling remains largely unclear. The sliding clamp proliferating cell nuclear antigen (PCNA) is an indispensable component of the DNA machinery responsible for replicating the genome and maintaining genomic integrity. We previously reported that epidermal growth factor receptor (EGFR) triggered tyrosine 211 (Y211) phosphorylation of PCNA, which in turn stabilized PCNA on chromatin to promote cell proliferation. Here we show that the phosphorylation can also be catalyzed by the non-receptor tyrosine kinase c-Abl. We further demonstrate that, in the absence of EGFR, signaling to PCNA can be attained through the activation of the Ron receptor tyrosine kinase and the downstream non-receptor tyrosine kinase c-Abl. We show that Ron and c-Abl form a complex, and that activation of Ron by its ligand, hepatocyte growth factor-like protein (HGFL), stimulates c-Abl kinase activity, which in turn directly phosphorylates PCNA at Y211 and leads to an increased level of chromatin-associated PCNA. Correspondingly, HGFL-induced Ron activation resulted in Y211 phosphorylation of PCNA while silencing of c-Abl blocked this effect. We show that c-Abl and Y211 phosphorylation of PCNA is an important axis downstream of Ron, which is required for cell proliferation. Treatment with a specific peptide that inhibits Y211 phosphorylation of PCNA or with the c-Abl pharmacological inhibitor imatinib suppressed HGFL-induced cell proliferation. Our findings identify the pathway of Ron-c-Abl-PCNA as a mechanism of oncogene-induced cell proliferation, with potentially important implications for development of combination therapy of breast cancer.


Asunto(s)
Neoplasias de la Mama/metabolismo , Proliferación Celular , Antígeno Nuclear de Célula en Proliferación/metabolismo , Proteínas Proto-Oncogénicas c-abl/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Femenino , Humanos , Fosforilación
5.
Oncogene ; 30(50): 4990-8, 2011 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-21625214

RESUMEN

The Ron receptor tyrosine kinase (TK) is overexpressed in many cancers, including prostate cancer. To examine the significance of Ron in prostate cancer in vivo, we utilized a genetically engineered mouse model, referred to as TRAMP mice, that is predisposed to develop prostate tumors. In this model, we show that prostate tumors from 30-week-old TRAMP mice have increased Ron expression compared with age-matched wild-type prostates. Based on the upregulation of Ron in human prostate cancers and in this murine model of prostate tumorigenesis, we hypothesized that this receptor has a functional role in the development of prostate tumors. To test this hypothesis, we crossed TRAMP mice with mice that are deficient in Ron signaling (TK-/-). Interestingly, TK-/- TRAMP+ mice show a significant decrease in prostate tumor mass relative to TRAMP mice containing functional Ron. Moreover, TK-/- TRAMP+ prostate tumors exhibited decreased tumor vascularization relative to TK+/+ TRAMP+ prostate tumors, which correlated with reduced levels of the angiogenic molecules vascular endothelial growth factor and CXCL2. Although Ron loss did not alter tumor cell proliferation, a significant decrease in cell survival was observed. Similarly, murine prostate cancer cell lines containing a Ron deficiency exhibited decreased levels of active nuclear factor-κB, suggesting that Ron may be important in regulating prostate cell survival at least partly through this pathway. In total, our data show for the first time that Ron promotes prostate tumor growth, prostate tumor angiogenesis and prostate cancer cell survival in vivo.


Asunto(s)
Proliferación Celular , Proteínas de Neoplasias/metabolismo , Neovascularización Patológica/metabolismo , Neoplasias de la Próstata/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Miembro 25 de Receptores de Factores de Necrosis Tumoral/metabolismo , Animales , Supervivencia Celular/genética , Quimiocina CXCL2/genética , Quimiocina CXCL2/metabolismo , Cruzamientos Genéticos , Modelos Animales de Enfermedad , Femenino , Humanos , Masculino , Ratones , Ratones Noqueados , FN-kappa B/genética , FN-kappa B/metabolismo , Proteínas de Neoplasias/genética , Neovascularización Patológica/genética , Neovascularización Patológica/patología , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Proteínas Tirosina Quinasas Receptoras/genética , Miembro 25 de Receptores de Factores de Necrosis Tumoral/genética
6.
Oncogene ; 30(34): 3694-704, 2011 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-21423209

RESUMEN

Our previous studies demonstrated that selective overexpression of the Ron receptor tyrosine kinase in the murine mammary epithelium leads to mammary tumor formation. Biochemical analysis of mammary tumor lysates showed that Ron overexpression was associated with increases in ß-catenin expression and tyrosine phosphorylation. ß-Catenin has also been shown to be regulated through tyrosine phosphorylation by the receptor tyrosine kinases Met, Fer and Fyn. However, the molecular and physiological roles of ß-catenin and ß-catenin tyrosine phosphorylation downstream of Ron are not known. To investigate this association, we show that Ron and ß-catenin are coordinately elevated in human breast cancers. Our data also demonstrate that activation of Ron, through ligand binding by hepatocyte growth factor-like protein (HGFL), induces the tyrosine phosphorylation of ß-catenin, primarily on tyrosine residues Tyr 654 and Tyr 670. In addition, HGFL-mediated Ron activation induces both ß-catenin nuclear localization and transcriptional activity, with Tyr 654 and Tyr 670 residues of ß-catenin being critical for these processes. We also demonstrate that a knockdown of Ron in breast cancer cell lines leads to a loss of HGFL-induced ß-catenin-dependent transcriptional activation and cell growth, which can be rescued by activation of canonical Wnt/ß-catenin signaling. Moreover, we show that HGFL-dependent Ron activation mediates upregulation of the ß-catenin target genes cyclin D1 and c-myc, and that expression of these target genes in breast cancer cells is decreased following inhibition of Ron and/or ß-catenin. Finally, we show that genetic ablation of ß-catenin in Ron-expressing breast cancer cells decreases cellular proliferation in vitro, as well as mammary tumor growth and metastasis, following orthotopic transplantation into the mammary fat pad. Together, our data suggest that ß-catenin is a crucial downstream regulator of Ron receptor activation and is an important mediator of mammary tumorigenesis.


Asunto(s)
Neoplasias Mamarias Experimentales/metabolismo , Proteínas Tirosina Quinasas Receptoras/fisiología , beta Catenina/metabolismo , Animales , Secuencia de Bases , Proliferación Celular , Cartilla de ADN , Inmunohistoquímica , Neoplasias Mamarias Experimentales/patología , Ratones , Fosforilación , Reacción en Cadena de la Polimerasa , Proteínas Tirosina Quinasas Receptoras/química , Proteínas Tirosina Quinasas Receptoras/metabolismo , Tirosina/metabolismo
7.
Oncogene ; 30(24): 2741-52, 2011 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-21317931

RESUMEN

Breast cancer is a major cause of cancer-related deaths in American women; therefore, the identification of novel breast cancer-related molecules for the discovery of new markers and drug targets remains essential. The human DEK gene, which encodes a chromatin-binding protein and DNA topology regulator, is upregulated in many types of cancer. DEK has been implicated as an oncogene in breast cancer based on mRNA expression studies, but its functional significance in breast cancer growth and progression has not yet been tested directly. We demonstrate that DEK is highly expressed in breast cancer cells compared with normal tissue, and functionally important for cellular growth, invasion and mammosphere formation. DEK overexpression in non-tumorigenic MCF10A cells resulted in increased growth and motility, with a concomitant downregulation of E-cadherin. Conversely, DEK knockdown in MCF7 and MDA-MB-468 breast cancer cells resulted in decreased growth and motility with upregulation of E-cadherin. The use of DEK-proficient and -deficient breast cancer cells in orthotopic xenografts provided further in vivo evidence that DEK contributes to tumor growth. Activation of the ß-catenin signaling pathway is important for normal and cancer stem cell character, growth and metastasis. We show that DEK expression stimulated, and DEK knockdown repressed ß-catenin nuclear translocation and activity. Importantly, the expression of constitutively active ß-catenin rescued breast cancer invasion defects of DEK knockdown cells. Together, our data indicate that DEK expression stimulates the growth, stem cell character and motility of breast cancer cells, and that DEK-dependent cellular invasion occurs at least in part via ß-catenin activation.


Asunto(s)
Neoplasias de la Mama/patología , Proteínas Cromosómicas no Histona/genética , Células Madre Neoplásicas/patología , Proteínas Oncogénicas/genética , Proto-Oncogenes , Transducción de Señal/fisiología , beta Catenina/fisiología , Animales , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Supervivencia Celular , Proteínas Cromosómicas no Histona/fisiología , Femenino , Humanos , Ratones , Invasividad Neoplásica , Proteínas Oncogénicas/fisiología , Proteínas de Unión a Poli-ADP-Ribosa
8.
Oncogene ; 29(2): 214-26, 2010 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-19838218

RESUMEN

Overexpression of the Ron receptor tyrosine kinase has recently been shown in a wide variety of human cancers. However, no studies have examined Ron receptor expression or function during prostate tumorigenesis. In this study we report that Ron is highly expressed in human prostate adenocarcinoma and metastatic lymph nodes when compared with normal prostate or benign prostate hyperplasia. Furthermore, we show that Ron is overexpressed in PC-3 and DU145 prostate cancer cell lines, and that the levels of angiogenic chemokines produced by prostate cancer cells positively correlate with Ron expression. The knockdown of Ron in PC-3 or DU145 cells results in a significant decrease in angiogenic chemokine production and is associated with a decreased activation of the transcription factor nuclear factor-kappaB (NF-kappaB). Moreover, exogenous overexpression of Ron in LNCaP cells is sufficient to induce a significant increase in angiogenic chemokines that can be abrogated by inhibition of NF-kappaB signaling. Given that the function of angiogenic chemokines is important in the development of new blood vessels, we also examined the ability of Ron to modulate endothelial cell migration. Our data show that knockdown of Ron in prostate cancer cells results in significantly less endothelial cell chemotaxis when compared with Ron-expressing cells in vitro as well as in reduced tumor growth and decreased microvessel density after orthotopic transplantation into the prostate in vivo. In total, our data suggest that the Ron receptor is important in modulating prostate tumor growth by modulating angiogenic chemokine production and subsequent endothelial cell recruitment.


Asunto(s)
Quimiocinas/metabolismo , FN-kappa B/metabolismo , Neoplasias de la Próstata/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Animales , Western Blotting , Línea Celular , Línea Celular Tumoral , Movimiento Celular , Quimiocina CXCL1/metabolismo , Quimiocina CXCL5/metabolismo , Células Endoteliales/citología , Células Endoteliales/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Interleucina-8/metabolismo , Masculino , Ratones , Ratones Desnudos , Neoplasias Experimentales/genética , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/patología , Neovascularización Patológica , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/metabolismo , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Interferencia de ARN , Proteínas Tirosina Quinasas Receptoras/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Trasplante Heterólogo
9.
Oncogene ; 20(43): 6142-51, 2001 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-11593422

RESUMEN

The receptor tyrosine kinase Ron is a member of the receptor family that includes the proto-oncogene Met and the avian oncogene Sea. The interaction of Ron with its ligand, known as hepatocyte growth factor-like protein (HGFL) or macrophage stimulating protein (MSP), induces crucial cellular responses including invasive growth, proliferation, cell scattering, and branching morphogenesis. Based on the homology and functional similarities between Met and Ron it was hypothesized that Ron may be important in tumor formation and metastasis. To test this hypothesis, wild-type mouse Ron and three mutant forms of Ron containing mutations similar to those found in the Met gene in human hereditary papillary renal carcinoma (HPRC), were expressed in NIH3T3 cells. A transformed phenotype was produced in cell lines expressing either wild-type Ron or the mutated Ron proteins. Further, these cell lines displayed oncogenic potential by exhibiting increased proliferation and constitutive phosphorylation of Ron. These cell lines were also tested for the ability to form solid tumors. Cells expressing wild-type Ron and the three proteins with single amino acid substitutions were highly tumorigenic in vivo. In a model of experimental metastasis, two of the cell lines with altered Ron protein formed highly aggressive tumors in the lungs. These results suggest that Ron may be an aggressive oncogene when either overexpressed or when activated by mutation.


Asunto(s)
Factor de Crecimiento de Hepatocito , Neoplasias/genética , Mutación Puntual , Proteínas Proto-Oncogénicas , Proteínas Tirosina Quinasas Receptoras/genética , Proteínas Tirosina Quinasas Receptoras/metabolismo , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/metabolismo , Células 3T3 , Secuencia de Aminoácidos , Animales , Western Blotting , Carcinoma/genética , División Celular , Transformación Celular Neoplásica , ADN Complementario/metabolismo , Sustancias de Crecimiento/metabolismo , Humanos , Neoplasias Renales/genética , Ligandos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundario , Ratones , Datos de Secuencia Molecular , Mutación , Metástasis de la Neoplasia , Fosforilación , Unión Proteica , Estructura Terciaria de Proteína , Proto-Oncogenes Mas , ARN/metabolismo , Proteínas Tirosina Quinasas Receptoras/fisiología , Receptores de Superficie Celular/fisiología , Homología de Secuencia de Aminoácido , Transfección , Células Tumorales Cultivadas
10.
J Clin Invest ; 108(4): 567-76, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11518730

RESUMEN

Ron receptor activation induces numerous cellular responses in vitro, including proliferation, dissociation, and migration. Ron is thought to be involved in blood cell development in vivo, as well as in many aspects of the immune response including macrophage activation, antigen presentation, and nitric oxide regulation. In previous studies to determine the function of Ron in vivo, mice were generated with a targeted deletion of the extracellular and transmembrane regions of this gene. Mice homologous for this deletion appear to die early during embryonic development. To ascertain the in vivo function of Ron in more detail, we have generated mice with a germline ablation of the tyrosine kinase domain. Strikingly, our studies indicate that this domain of Ron, and therefore Ron cytoplasmic signaling, is not essential for embryonic development. While mice deficient in this domain are overtly normal, mice lacking Ron signaling have an altered ability to regulate nitric oxide levels and, in addition, have enhanced tissue damage following acute and cell-mediated inflammatory responses.


Asunto(s)
Sustancias de Crecimiento/fisiología , Factor de Crecimiento de Hepatocito , Inflamación/metabolismo , Proteínas Proto-Oncogénicas , Proteínas Tirosina Quinasas Receptoras/fisiología , Receptores de Superficie Celular/fisiología , Transducción de Señal , Animales , Células CHO , Células Cultivadas , Cricetinae , Cricetulus , Dermatitis Alérgica por Contacto/etiología , Dermatitis Alérgica por Contacto/inmunología , Dermatitis Alérgica por Contacto/patología , Dermatitis por Contacto/etiología , Dermatitis por Contacto/inmunología , Dermatitis por Contacto/patología , Dinitrofluorobenceno/toxicidad , Desarrollo Embrionario y Fetal/fisiología , Femenino , Genes Letales , Sustancias de Crecimiento/farmacología , Inflamación/etiología , Irritantes/toxicidad , Activación de Macrófagos , Macrófagos Peritoneales/fisiología , Ratones , Ratones Noqueados , Óxido Nítrico/metabolismo , Especificidad de Órganos , Ovario/metabolismo , Ovario/patología , Fenol/toxicidad , Fosforilación , Fosfotirosina/biosíntesis , Procesamiento Proteico-Postraduccional/genética , Estructura Terciaria de Proteína , Proteínas Tirosina Quinasas Receptoras/química , Proteínas Tirosina Quinasas Receptoras/efectos de los fármacos , Proteínas Tirosina Quinasas Receptoras/genética , Receptores de Superficie Celular/química , Receptores de Superficie Celular/efectos de los fármacos , Receptores de Superficie Celular/genética , Método Simple Ciego , Estrés Fisiológico/complicaciones
11.
Neuropediatrics ; 31(2): 82-5, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10832582

RESUMEN

PURPOSE: To investigate the mode of inheritance of the photoparoxysmal response (PPR) and to obtain more information about the influence of photosensitivity on the seizure risk in siblings of patients with epilepsy. METHODS: Examination of the records of families with one photosensitive parent (Group I, n = 54) and of families with a photosensitive proband, neither of whose parents was photosensitive (Group II, n = 72). RESULTS: At the age of maximum penetrance, between 5 and 15 years of age, 50% of the siblings in Group I were photosensitive, compared to only 15% in Group II. Siblings in Group I showed a higher seizure rate (19%) than siblings in Group II (4%, p < 0.005). The majority of photosensitive siblings had no seizures, but photosensitive siblings had a higher seizure risk than non-photosensitive siblings. The highest seizure risk was found in photosensitive siblings of Group I (33%) compared to 9% in non-photosensitive siblings (p < 0.05). CONCLUSION: Our findings show that a PPR in parents is a major determinant for the risk of a PPR in offspring. The results may indicate an autosomal-dominant transmission with age-dependent penetrance of the PPR. Photosensitivity is an important factor in the pathogenesis of seizure disorders in childhood.


Asunto(s)
Epilepsia Refleja/genética , Adolescente , Adulto , Niño , Preescolar , Epilepsia Refleja/diagnóstico , Femenino , Expresión Génica , Predisposición Genética a la Enfermedad/genética , Humanos , Lactante , Masculino , Persona de Mediana Edad , Factores de Riesgo
12.
Neurophysiol Clin ; 29(4): 318-24, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10546250

RESUMEN

RATIONALE: In many EEG laboratories in Europe, intermittent photic stimulation (IPS) is not performed routinely, and consequently, great variation exists in the type of photo stimulator used, the methodology employed, and the interpretation of the EEG curves, thus leading to different outcomes. METHODOLOGY: It was decided to hold a consensus meeting with experts in the field of photic stimulation from various European countries. This meeting was held at the Stichting Epilepsie Instellingen Nederland, Heemstede, the Netherlands. The consensus reached was presented and discussed at the 9th European Congress of Clinical Neurophysiology in Ljubjana in June 1998. RESULTS: Patients should be positioned at a distance of 30 cm from the photic stimulator (nasion to lamp) with dim surrounding lights, just enough to see the patient. Flashes should be delivered in separate trains of 10 s for each frequency, with intervals of 7 s minimum. First stimulation occurs with eyes open followed after 5 s by eye closure, while starting at 1 Hz progressing to 20 Hz, unless generalised epileptiform discharges are evoked at a lower frequency. Then, frequencies should start at 60 Hz decreasing to 25 Hz. The following frequencies should be used: 1, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 60, 50, 40, 30 and 25 Hz. The total duration is a maximum of 6 min (patients without a reaction to IPS). In interpreting the evoked responses, a clear distinction should be made between epileptiform responses confined to the occipital area (OSW), starting occipitally and spreading to frontal regions (OGSW), or generalised from the start (GSW). Other responses include generalised spikes (OR). CONCLUSION: This standard is safe, relatively quick, simple and reliable. Comparison of data within patients and between patients of various laboratories will also be possible. This will improve the quality of the care of the individual patient and make collaborative research possible.


Asunto(s)
Electroencefalografía/normas , Estimulación Luminosa , Electroencefalografía/instrumentación , Europa (Continente) , Humanos , Estimulación Luminosa/métodos
13.
J Clin Invest ; 103(9): 1277-85, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10225971

RESUMEN

The Ron/STK receptor tyrosine kinase is a member of the c-Met family of receptors and is activated by hepatocyte growth factor-like protein (HGFL). Ron activation results in a variety of cellular responses in vitro, such as activation of macrophages, proliferation, migration, and invasion, suggesting a broad biologic role in vivo. Nevertheless, HGFL-deficient mice grow to adulthood with few appreciable phenotypic abnormalities. We report here that in striking contrast to the loss of its only known ligand, complete loss of Ron leads to early embryonic death. Embryos that are devoid of Ron (Ron-/-) are viable through the blastocyst stage of development but fail to survive past the peri-implantation period. In situ hybridization analysis demonstrates that Ron is expressed in the trophectoderm at embryonic day (E) 3.5 and is maintained in extraembryonic tissue through E7.5, compatible with an essential function at this stage of development. Hemizygous mice (Ron+/-) grow to adulthood; however, these mice are highly susceptible to endotoxic shock and appear to be compromised in their ability to downregulate nitric oxide production. These results demonstrate a novel role for Ron in early mouse development and suggest that Ron plays a limiting role in the inflammatory response.


Asunto(s)
Implantación del Embrión , Proteínas Tirosina Quinasas Receptoras/metabolismo , Receptores de Superficie Celular/metabolismo , Animales , Secuencia de Bases , Cartilla de ADN , Desarrollo Embrionario y Fetal , Femenino , Muerte Fetal/genética , Factor de Crecimiento de Hepatocito/genética , Factor de Crecimiento de Hepatocito/metabolismo , Hibridación in Situ , Ratones , Óxido Nítrico/fisiología , Proteínas Tirosina Quinasas Receptoras/genética , Receptores de Superficie Celular/genética , Choque Séptico/genética , Células Madre/metabolismo
14.
Fortschr Neurol Psychiatr ; 67(3): 122-30, 1999 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-10214556

RESUMEN

The available scientific literature rarely addresses the important practical issue of how to establish and withdraw antiepileptic treatment. Initiation of antiepileptic therapy is mainly based on personal experience. With regard to the few data focussing on this topic and on the background of the authors' personal experience and discussions with other experienced epileptologists the authors attempt to propose a rational concept. Age-related pharmacokinetic properties of anti-epileptic drugs are discussed. Recommendations for initial starting dose, titration procedures, target dosages and number of daily doses for both standard and new antiepileptic drugs are given. Dosages for children are given on a mg/kg body weight basis. Indications and limitations for determination of drug levels are provided. Withdrawal of antiepileptic therapy has been subject of recent prospective studies in children and adults providing important prognostic factors. Etiology of the epilepsy, syndromic classification, results of neurological investigation, EEG and the personal situation of the patients have to be considered. Current knowledge is reviewed with emphasis on practical aspects of when and how to withdraw antiepileptic drugs. This review emphasizes the urgent need of further prospective studies.


Asunto(s)
Anticonvulsivantes/administración & dosificación , Anticonvulsivantes/uso terapéutico , Epilepsia/tratamiento farmacológico , Adulto , Envejecimiento/fisiología , Niño , Humanos
15.
Endocrinology ; 140(1): 187-96, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9886825

RESUMEN

In an effort to understand the molecular mechanisms involved in the regulation of expression of the gene encoding hepatocyte growth factor-like protein (HGFL), it was found that all-trans-retinoic acid dramatically represses expression of the endogenous HGFL gene in HepG2 cells, a human hepatocyte-derived cell line. This repression requires the sequence between nucleotides -135 and -105 in the 5'-flanking sequence of the HGFL gene, a site that has previously been shown to bind the transcription factor hepatocyte nuclear factor-4 (HNF-4). Electrophoretic mobility shift analysis suggests that the retinoic acid receptor does not bind to this site, and that retinoic acid does not alter binding of HNF-4 to this DNA site. However, the transcriptional coactivator, CREB-binding protein (CBP) coactivates expression of this gene through an indirect interaction with the HNF-4-binding site, and overexpression of CBP in HepG2 cells eliminates retinoic acid repression of reporter gene expression driven by the HGFL promoter. Overexpression of CBP also protects the endogenous HGFL gene from down-regulation by retinoic acid. These results suggest that HGFL gene expression requires CBP, and competition for limiting amounts of CBP by retinoic acid receptor may be a means of modifying the activity of HNF-4 at the HGFL gene promoter.


Asunto(s)
Proteínas de Unión al ADN , Regulación de la Expresión Génica/efectos de los fármacos , Sustancias de Crecimiento/biosíntesis , Factor de Crecimiento de Hepatocito , Proteínas Nucleares/farmacología , Proteínas Proto-Oncogénicas , Proteínas Represoras/farmacología , Transactivadores/farmacología , Tretinoina/farmacología , Secuencia de Bases , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice , Proteína de Unión a CREB , Línea Celular , ADN/metabolismo , Sustancias de Crecimiento/genética , Factor Nuclear 4 del Hepatocito , Humanos , Datos de Secuencia Molecular , Fosfoproteínas/metabolismo , Regiones Promotoras Genéticas , Unión Proteica , Receptores de Ácido Retinoico/metabolismo , Factores de Transcripción/metabolismo
16.
Neuropediatrics ; 29(5): 229-38, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9810557

RESUMEN

PURPOSE: While the literature on infantile epilepsies with minor and major seizures is extensive, little consideration has been given to infantile epilepsy with generalized tonic-clonic seizures (GTCS) alone. The aim of the present study was to analyze the data of a large group of patients and their families to obtain further insight into the clinical picture and pathogenesis of this type of epilepsy. METHODS: The 101 children (58 boys, 43 girls) met the following inclusion criteria: onset of the epilepsy with febrile or afebrile GTCS in the first 5 years of life, absence of primary organic brain lesion or progressive brain disease, severe course with frequent febrile and/or afebrile GTCS, failure of conventional anticonvulsive therapy. RESULTS: The epilepsy predominantly afflicts normally developed infants, boys and girls being about equally affected. The epilepsy begins with frequent febrile or afebrile GTCS, characteristically of long duration and often with alternating lateralization. In half of the cases additional myoclonic or myoclonic astatic seizures and/or absences occur. The initial GTCS phase is the same in epilepsies with and without minor seizures. Erratic myoclonias are especially characteristic. With advancing age, the symptomatology becomes increasingly polymorphic due to the occurrence of additional simple and complex focal and tonic seizures. Severe impairment of mental development soon after onset is a leading symptom. The overall death rate was 9%. Only 11% of the patients had been seizure-free for at least two years at final examination. The EEG was initially normal and subsequently exhibited diffuse 4-7/s rhythms, and only later spikes and waves of irregular shape (87%). Focal sharp waves occurred transiently in 26%. The family history and EEG of probands and relatives showed the pathogenesis to be decisively determined by genetic factors. CONCLUSION: Early infantile GTCS epilepsy represents a genetically determined (idiopathic) epileptic encephalopathy. It overlaps with other forms of early childhood epilepsy such as severe myoclonic epilepsy, severe type of myoclonic astatic epilepsy, as well as early childhood absence epilepsy with GTCS.


Asunto(s)
Epilepsia/diagnóstico , Epilepsia/etiología , Convulsiones Febriles/etiología , Edad de Inicio , Anticonvulsivantes/uso terapéutico , Niño , Preescolar , Progresión de la Enfermedad , Electroencefalografía , Epilepsia/tratamiento farmacológico , Epilepsia/mortalidad , Epilepsia Tónico-Clónica/diagnóstico , Epilepsia Tónico-Clónica/tratamiento farmacológico , Epilepsia Tónico-Clónica/etiología , Composición Familiar , Femenino , Predisposición Genética a la Enfermedad , Humanos , Lactante , Discapacidad Intelectual/etiología , Masculino , Estudios Retrospectivos , Convulsiones Febriles/tratamiento farmacológico , Tasa de Supervivencia , Insuficiencia del Tratamiento , Vacunación
17.
DNA Cell Biol ; 17(10): 885-96, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9809750

RESUMEN

At supramolecular resolution, DNA synthesis begins at preferred replication origins in the chromosomes of metazoan cells. To characterize one of these origins in detail, the initiation of replication was examined in the HeLa c-myc origin. Polymerase chain reaction (PCR) amplification of size-fractionated nascent chromosomal DNAs revealed multiple replication initiation sites over a 12-kb region spanning the c-myc origin, including the transcribed region and the 5' and 3' flanking DNA of the gene. Two of the start sites for chromosomal replication occurred inside a 2.4-kb region of the origin that exhibits autonomously replicating sequence (ARS) activity. When a plasmid containing the 2.4-kb ARS region was transfected into HeLa cells, PCR mapping of nascent plasmid DNA confirmed that the plasmid replicated semiconservatively and autonomously and that replication did not initiate at random sites but rather began at multiple sites in a limited zone overlapping the c-myc DNA insert. Within the resolution of the PCR assay, the same sites that were used in the chromosomal c-myc origin were used in the 2.4-kb ARS fragment. The locations of replication start sites determined by PCR are considered in the context of other functional and structural elements of the c-myc origin.


Asunto(s)
Mapeo Cromosómico , Genes myc , Origen de Réplica , Polaridad Celular , Cartilla de ADN , Replicación del ADN , Células HeLa , Humanos , Reacción en Cadena de la Polimerasa , Proteínas Proto-Oncogénicas c-myc/biosíntesis , Proteínas Proto-Oncogénicas c-myc/genética , Mapeo Restrictivo , Transcripción Genética , Transfección
18.
Oncogene ; 16(1): 27-42, 1998 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-9467940

RESUMEN

In an effort to understand the mechanisms governing the regulation of the mouse Ron receptor gene, a mouse genomic library was screened and overlapping clones coding for the Ron gene and flanking DNA were identified. Continuous DNA sequence was obtained for approximately 16.4 kilobases. The gene, from the initiator methionine to the polyadenylation site, is contained within 13 244 basepairs and contains 19 exons. Primer extension analyses were performed to determine the transcription start site of the mouse Ron transcript. Multiple transcription start sites were found which also appear to be used in transfected reporter constructs containing Ron 5' flanking DNA. To determine the location of sites which may be critical for the function of the Ron gene promoter, a series of chimeric genes containing serial deletions of the Ron gene promoter fused to the coding sequences for the chloramphenicol acetyl-transferase gene were constructed. Transient transfection analyses of these hybrid genes into various cell lines demonstrated that two regions of the Ron gene promoter, encompassing nucleotides -585 to -465 and from -465 to -285, are important for expression of this transcript in CMT-93 cells. Further analysis of the Ron promoter utilizing gel mobility shift analyses suggests that regions encompassing nucleotides -585 to - 508 and nucleotides -375 to -285 appear to bind specific proteins which may be involved in the negative and positive regulation, respectively, of the mouse Ron gene.


Asunto(s)
Proteínas Tirosina Quinasas Receptoras/genética , Receptores de Superficie Celular/genética , Células 3T3 , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Sitios de Unión , Cloranfenicol O-Acetiltransferasa/genética , Cartilla de ADN , ADN Complementario , Ratones , Datos de Secuencia Molecular , Proteínas Nucleares/metabolismo , Plásmidos , Regiones Promotoras Genéticas , ARN Mensajero/genética , Eliminación de Secuencia , Transcripción Genética , Transfección , Células Tumorales Cultivadas
20.
DNA Seq ; 8(6): 409-13, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-10728827

RESUMEN

The human chromosome 3 locus coding for hepatocyte growth factor-like protein/macrophage stimulating protein (HGFL/MSP) is homologous to two sets of amplified loci on human chromosome 1 at 1p36. One copy of one of the amplified loci (D1F15S1A) has been further characterized by restriction enzyme and DNA sequence analysis. A total of 8331 bp of continuous sequence was determined for this locus. The first 6878 bp of sequence is 96.1% identical to the HGFL/MSP gene, while there is no homology between the two genes following nucleotide 6878. Based on the presence of a 5 bp deletion in putative exon 2 and several downstream stop codons it is very likely that this gene is a pseudogene. Screening of a human liver cDNA library with a chromosome 1-specific probe indicates that at least several other members of the chromosome 1 loci are transcribed.


Asunto(s)
Cromosomas Humanos Par 1/genética , Cromosomas Humanos Par 3/genética , Sustancias de Crecimiento/genética , Factor de Crecimiento de Hepatocito , Proteínas Proto-Oncogénicas , Clonación Molecular , Sondas de ADN , Humanos , Hígado/metabolismo , Seudogenes/genética , Mapeo Restrictivo , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido Nucleico
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