Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 36
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
Magy Seb ; 70(1): 69-73, 2017 03.
Artículo en Húngaro | MEDLINE | ID: mdl-28294664

RESUMEN

Inflammatory fibroid polyp (IFP) is an uncommon benign tumor of the gastrointestinal tract. IFP in the esophagus is very rare, in particular in giant size. A case of a 63 year old woman with a 13 × 7 × 4.5 cm polyp originated of the lower third of the oesophagus is presented. Her esophageal polyp extended proximally from the level of the tracheal bifurcation, prolapsing through the cardia as well as the herniated stomach, and entered distally into the abdominal part of the stomach. Resection of the polyp was performed via a right oesophago-gastrotomy. Histology verified inflammatory fibroid polyp of the esophagus. An overview of clinical features of the inflammatory fibroid polyp is presented in connection of our case report.


Asunto(s)
Enfermedades del Esófago/patología , Enfermedades del Esófago/cirugía , Gastrectomía/métodos , Leiomioma/patología , Leiomioma/cirugía , Pólipos/patología , Pólipos/cirugía , Enfermedades del Esófago/diagnóstico , Neoplasias Esofágicas/cirugía , Femenino , Humanos , Persona de Mediana Edad , Pólipos/diagnóstico , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugía , Resultado del Tratamiento
2.
Arch Dermatol Res ; 306(10): 885-902, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25318378

RESUMEN

TASK-3 (KCNK9 or K2P9.1) channels are thought to promote proliferation and/or survival of malignantly transformed cells, most likely by increasing their hypoxia tolerance. Based on our previous results that suggested mitochondrial expression of TASK-3 channels, we hypothesized that TASK-3 channels have roles in maintaining mitochondrial activity. In the present work we studied the effect of reduced TASK-3 expression on the mitochondrial function and survival of WM35 and A2058 melanoma cells. TASK-3 knockdown cells had depolarized mitochondrial membrane potential and contained a reduced amount of mitochondrial DNA. Compared to their scrambled shRNA-transfected counterparts, they demonstrated diminished responsiveness to the application of the mitochondrial uncoupler [(3-chlorophenyl)hydrazono]malononitrile (CCCP). These observations indicate impaired mitochondrial function. Further, TASK-3 knockdown cells presented reduced viability, decreased total DNA content, altered cell morphology, and reduced surface area. In contrast to non- and scrambled shRNA-transfected melanoma cell lines, which did not present noteworthy apoptotic activity, almost 50 % of the TASK-3 knockdown cells exhibited strong Annexin-V-specific immunofluorescence signal. Sequestration of cytochrome c from the mitochondria to the cytosol, increased caspase 3 activity, and translocation of the apoptosis-inducing factor from mitochondria to cell nuclei were also demonstrated in TASK-3 knockdown cells. Interference with TASK-3 channel expression, therefore, induces caspase-dependent and -independent apoptosis of melanoma cells, most likely via causing mitochondrial depolarization. Consequently, TASK-3 channels may be legitimate targets of future melanoma therapies.


Asunto(s)
Apoptosis , Melanoma/metabolismo , Potencial de la Membrana Mitocondrial , Mitocondrias/metabolismo , Canales de Potasio de Dominio Poro en Tándem/deficiencia , Interferencia de ARN , Neoplasias Cutáneas/metabolismo , Proteínas Reguladoras de la Apoptosis/metabolismo , Línea Celular Tumoral , Proliferación Celular , Regulación hacia Abajo , Metabolismo Energético , Regulación Neoplásica de la Expresión Génica , Humanos , Melanoma/genética , Melanoma/patología , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/patología , Canales de Potasio de Dominio Poro en Tándem/genética , Transducción de Señal , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Factores de Tiempo , Transfección , Desacopladores/farmacología
3.
Eur J Neurosci ; 37(6): 876-90, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23301797

RESUMEN

Giant cells of the cochlear nucleus are thought to integrate multimodal sensory inputs and participate in monaural sound source localization. Our aim was to explore the significance of a hyperpolarization-activated current in determining the activity of giant neurones in slices prepared from 10 to 14-day-old rats. When subjected to hyperpolarizing stimuli, giant cells produced a 4-(N-ethyl-N-phenylamino)-1,2-dimethyl-6-(methylamino) pyridinium chloride (ZD7288)-sensitive inward current with a reversal potential and half-activation voltage of -36 and -88 mV, respectively. Consequently, the current was identified as the hyperpolarization-activated non-specific cationic current (Ih ). At the resting membrane potential, 3.5% of the maximum Ih conductance was available. Immunohistochemistry experiments suggested that hyperpolarization-activated, cyclic nucleotide-gated, cation non-selective (HCN)1, HCN2, and HCN4 subunits contribute to the assembly of the functional channels. Inhibition of Ih hyperpolarized the membrane by 6 mV and impeded spontaneous firing. The frequencies of spontaneous inhibitory and excitatory postsynaptic currents reaching the giant cell bodies were reduced but no significant change was observed when evoked postsynaptic currents were recorded. Giant cells are affected by biphasic postsynaptic currents consisting of an excitatory and a subsequent inhibitory component. Inhibition of Ih reduced the frequency of these biphasic events by 65% and increased the decay time constants of the inhibitory component. We conclude that Ih adjusts the resting membrane potential, contributes to spontaneous action potential firing, and may participate in the dendritic integration of the synaptic inputs of the giant neurones. Because its amplitude was higher in young than in adult rats, Ih of the giant cells may be especially important during the postnatal maturation of the auditory system.


Asunto(s)
Núcleo Coclear/fisiología , Células Gigantes/fisiología , Transporte Iónico , Potenciales de la Membrana , Neuronas/fisiología , Animales , Cationes/metabolismo , Membrana Celular/fisiología , Núcleo Coclear/citología , Canales Catiónicos Regulados por Nucleótidos Cíclicos/antagonistas & inhibidores , Canales Catiónicos Regulados por Nucleótidos Cíclicos/metabolismo , Potenciales Postsinápticos Excitadores , Células Gigantes/metabolismo , Potenciales Postsinápticos Inhibidores , Neuronas/metabolismo , Multimerización de Proteína , Subunidades de Proteína/antagonistas & inhibidores , Subunidades de Proteína/metabolismo , Pirimidinas/farmacología , Ratas , Ratas Wistar
4.
Brain Struct Funct ; 218(5): 1279-92, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23052547

RESUMEN

Correct interpretation of functional data obtained from various cell types of the cochlear nucleus (CN), a structure involved in auditory information processing, necessitates reliable cell identification. Our aim was to perform a quantitative morphological characterization of giant and pyramidal cells of the rat CN and identify parameters that are suitable for their adequate classification. Neurons were labeled with biocytin, visualized with a fluorescent marker, and three-dimensionally reconstructed from confocal images. The size and shape of the soma and dendritic tree of each neuron were characterized by 17 morphometric parameters. The variables were subjected to multivariate statistical analysis to determine their importance while discriminating between giant and pyramidal cells. Our results provide a new battery of morphometric data, which could not be obtained earlier, improve the chances of correct cell identification, make modeling experiments easier and more reliable, and help us to understand both the functions of individual CN neurons and the network properties of this nucleus. In addition, we demonstrate that even partial labeling and/or incomplete reconstruction of neurons may be enough for their correct identification if selected parameters describing the cell bodies and the proximal portions of the dendritic trees are utilized. We propose that our findings have specific relevance to studies which attempt cell identification after functional experiments resulting in incomplete labeling of the investigated neurons.


Asunto(s)
Núcleo Coclear/citología , Células Piramidales/citología , Animales , Tamaño de la Célula , Fluorescencia , Imagenología Tridimensional , Lisina/análogos & derivados , Microscopía Confocal , Análisis Multivariante , Ratas
5.
J Neurochem ; 123(1): 84-99, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22817114

RESUMEN

Protein phosphatase-1M (PP1M, myosin phosphatase) consists of a PP1 catalytic subunit (PP1c) and the myosin phosphatase target subunit-1 (MYPT1). RhoA-activated kinase (ROK) regulates PP1M via inhibitory phosphorylation of MYPT1. Using multidisciplinary approaches, we have studied the roles of PP1M and ROK in neurotransmission. Electron microscopy demonstrated the presence of MYPT1 and ROK in both pre- and post-synaptic terminals. Tautomycetin (TMC), a PP1-specific inhibitor, decreased the depolarization-induced exocytosis from cortical synaptosomes. trans-4-[(1R)-1-aminoethyl]-N-4-pyridinylcyclohexanecarboxamide dihydrochloride, a ROK-specific inhibitor, had the opposite effect. Mass spectrometry analysis identified several MYPT1-bound synaptosomal proteins, of which interactions of synapsin-I, syntaxin-1, calcineurin-A subunit, and Ca(2+) /calmodulin-dependent kinase II with MYPT1 were confirmed. In intact synaptosomes, TMC increased, whereas Y27632 decreased the phosphorylation levels of MYPT1(Thr696) , myosin-II light chain(Ser19) , synapsin-I(Ser9) , and syntaxin-1(Ser14) , indicating that PP1M and ROK influence their phosphorylation status. Confocal microscopy indicated that MYPT1 and ROK are present in the rat ventral cochlear nucleus both pre- and post-synaptically. Analysis of the neurotransmission in an auditory glutamatergic giant synapse demonstrated that PP1M and ROK affect neurotransmission via both pre- and post-synaptic mechanisms. Our data suggest that both PP1M and ROK influence synaptic transmission, but further studies are needed to give a full account of their mechanism of action.


Asunto(s)
Corteza Cerebral/ultraestructura , Exocitosis/fisiología , Ácido Glutámico/metabolismo , Proteína Fosfatasa 1/metabolismo , Sinapsis/metabolismo , Transmisión Sináptica/fisiología , Sinaptosomas/metabolismo , Quinasas Asociadas a rho/metabolismo , Animales , Animales Recién Nacidos , Calcio/metabolismo , Miosinas Cardíacas/metabolismo , Inhibidores Enzimáticos/farmacología , Potenciales Postsinápticos Excitadores/efectos de los fármacos , Potenciales Postsinápticos Excitadores/fisiología , Femenino , Inmunoprecipitación , Técnicas In Vitro , Masculino , Espectrometría de Masas , Microscopía Electrónica de Transmisión , Cadenas Ligeras de Miosina/metabolismo , Técnicas de Placa-Clamp , Fosforilación , Unión Proteica/efectos de los fármacos , Proteína Fosfatasa 1/ultraestructura , Proteínas Qa-SNARE/metabolismo , Ratas , Ratas Wistar , Serina/metabolismo , Sinapsis/ultraestructura , Sinapsinas/metabolismo , Sinaptosomas/ultraestructura , Treonina/metabolismo , Quinasas Asociadas a rho/ultraestructura
6.
J Cardiothorac Surg ; 7: 56, 2012 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-22713743

RESUMEN

BACKGROUND: The tumorous infiltration or carcinosis of the pericardium could cause pericardial effusion in up to one-third of cases of malignancy, thus potentially interfere with the otherwise desirable oncological treatment. The existing surgical methods for the management of pericardial fluid are well-established but are not without limitations in the symptomatic relief of malignant pericardial effusion (MPE). The recurrence rate ranges between 43 and 69% after pericardiocentesis and 9 to 16% after pericardial drainage. The desire to overcome relative limitations of the existing methods led us to explore an alternative approach. METHODS: The standard armamentarium of the Carlens collar mediastinoscopy procedure was utilized in a Chamberlain parasternal approach of the pericardial sac. The laterality of approach was decided based upon the pleural involvement, as tumor-free pericardiopleural reflection is required. A pericardio-pleural window at least 3 cm in diameter was created. From January 2000 to December 2009, 22 cases were operated on with mediastinoscope-controlled parasternal fenestration (MCPF). Considering the type of the primary tumor, there were 11 lung cancer, 6 breast cancers, 2 haematologic malignancies and in 3 patients the origin of malignancy could not be verified. RESULTS: There were no operative deaths. We lost one patient (4.5%) in the postoperative hospital period. All of the surviving patients had a minimum of 2 months of symptom-free survival. We detected transient recurrence of MPE in one patient (4.5%) 14 days after the MCPF, which disappeared spontaneously after 24 hours. CONCLUSION: The MCPF offers a real alternative in certain cases of pericardial effusion. We recommend this method especially for the definitive surgical palliation of MPE.


Asunto(s)
Neoplasias Cardíacas/cirugía , Mediastinoscopía/métodos , Derrame Pericárdico/cirugía , Técnicas de Ventana Pericárdica , Adulto , Anciano , Femenino , Neoplasias Cardíacas/secundario , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Neoplasias/patología
7.
Pflugers Arch ; 463(6): 829-44, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22547003

RESUMEN

Acetylcholine modulates the function of the cochlear nucleus via several pathways. In this study, the effects of cholinergic stimulation were studied on the cytoplasmic Ca(2+) concentration of granule neurones of the rat dorsal cochlear nucleus (DCN). Ca(2+) transients were recorded in Oregon-Green-BAPTA 1-loaded brain slices using a calcium imaging technique. For the detection, identification and characterisation of the Ca(2+) transients, a wavelet analysis-based method was developed. Granule cells were identified on the basis of their size and localisation. The action potential-coupled character of the Ca(2+) transients of the granule cells was established by recording fluorescence changes and electrical activity simultaneously. Application of the cholinergic agonist carbamyl-choline (CCh) significantly increased the frequency of the Ca(2+) transients (from 0.37 to 6.31 min(-1), corresponding to a 17.1-fold increase; n = 89). This effect was antagonised by atropine, whereas CCh could still evoke an 8.3-fold increase of the frequency of the Ca(2+) transients when hexamethonium was present. Using immunolabelling, the expression of both type 1 and type 3 muscarinic receptors (M1 and M3 receptors, respectively) was demonstrated in the granule cells. Application of 1,1-dimethyl-4-diphenylacetoxypiperidinium iodide (an M3-specific antagonist) prevented the onset of the CCh effect, whereas an M1-specific antagonist (pirenzepine) was less effective. We conclude that cholinergic stimulation increases the activity of granule cells, mainly by acting on their M3 receptors. The modulation of the firing activity of the granule cells, in turn, may modify the firing of projection neurones and may adjust signal processing in the entire DCN.


Asunto(s)
Calcio/metabolismo , Núcleo Coclear/metabolismo , Neuronas/citología , Neuronas/metabolismo , Receptores Muscarínicos/metabolismo , Acetilcolina/farmacología , Potenciales de Acción/efectos de los fármacos , Animales , Atropina/farmacología , Carbacol/farmacología , Núcleo Coclear/citología , Femenino , Masculino , Agonistas Muscarínicos/farmacología , Antagonistas Muscarínicos/farmacología , Neuronas/efectos de los fármacos , Técnicas de Placa-Clamp , Pirenzepina/farmacología , Ratas , Ratas Wistar
8.
Orv Hetil ; 153(14): 553-8, 2012 Apr 08.
Artículo en Húngaro | MEDLINE | ID: mdl-22450144

RESUMEN

The authors present the case of a 72-year-old woman who underwent coronary bypass grafting. Left sided chylothorax due to accidental dissection of a thoracic duct branch developed 2 months after sternotomy. As conservative therapy has failed, surgical pleurodesis was performed successfully. Chylothorax is a rare and underestimated complication of coronary bypass grafting. The worldwide increasing number of coronary artery bypass grafting surgeries makes it important to pay attention to this condition. Thus diagnosis of the chyle is relatively easy by its high chylomicron and triglyceride content, but identification of the etiology and its treatment is sometimes challenging for the physician. The treatment of chylothorax is usually conservative. The main goal is to keep the volume of the chyle under control. The number of surgical interventions because of chylothorax is increasing due to an increase of iatrogenic etiology.


Asunto(s)
Quilotórax/etiología , Quilotórax/cirugía , Puente de Arteria Coronaria/efectos adversos , Pleurodesia , Anciano , Quilotórax/diagnóstico , Quilotórax/terapia , Femenino , Humanos , Enfermedad Iatrogénica , Toracotomía , Tomografía Computarizada por Rayos X
9.
Melanoma Res ; 21(4): 308-22, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21512417

RESUMEN

TASK-3 channel overexpression was shown to facilitate the survival of malignantly transformed cells, possibly by providing greater hypoxia tolerance through a still unknown mechanism. Although it has been suggested previously that TASK-3 channels are expressed in the mitochondrial membranes, their role here remains elusive. In this study, a transient transfection of TASK-3 knockdown melanoma cell cultures was produced to show the significance of TASK-3 expression. Reduction of the TASK-3 protein biosynthesis induced characteristic changes in cell morphology, reduced the amount of DNA and decreased metabolic activity and mitochondrial function of melanoma cells when compared with control. These findings indicate that TASK-3 channel expression and function is indispensable for the proliferation and/or survival of the melanoma cells, as they seem to contribute to their mitochondrial functions. The significance is that, in this study, we have shown that TASK-3 channels are expressed in the mitochondria of melanoma malignum cells, and they are essential for maintaining cellular integrity and viability. The TASK-3 knockdown melanoma cell line had altered morphology, reduced DNA content, decreased metabolic activity and impaired mitochondrial function. These data indicate that TASK-3 channels are functionally present in the mitochondria of the melanoma cells, and their function is essential for the survival of these cells, thus TASK-3 channels may be the possible targets of future anticancer therapy.


Asunto(s)
Forma de la Célula , ADN/metabolismo , Melanoma/metabolismo , Mitocondrias/metabolismo , Canales de Potasio de Dominio Poro en Tándem/biosíntesis , Línea Celular Tumoral , Proliferación Celular , Tamaño de la Célula , Supervivencia Celular , Metabolismo Energético , Células HEK293 , Humanos , Melanoma/genética , Melanoma/patología , Mitocondrias/patología , Canales de Potasio de Dominio Poro en Tándem/genética , Interferencia de ARN , Factores de Tiempo , Transfección
10.
Magy Seb ; 64(1): 22-7, 2011 Feb.
Artículo en Húngaro | MEDLINE | ID: mdl-21330260

RESUMEN

Numerous methods exist for the treatment of pericardial effusions. These methods, however, can be applied with limitations only for long-term eradication of malignant pericardial effusion. Lately, several new methods, including minimally invasive procedures, have been published, and the VATS technique has become fairly popular. This technique needs special instruments and single lung ventilation, which is relatively risky in case of contralateral malignancy. We apply a new and simple minimally invasive fenestration method using the well-known approach of the parasternal mediastinoscopy by Stemmer. No recurrence of pericardial effusions was noted in long-term follow-up. In the past 10 years 73 patients were treated for pericardial effusion in our department and 22 pericardium fenestrations have been performed with parasternal approach. This method is recommended for the definitive treatment of pericardial effusion with malignant origin.


Asunto(s)
Taponamiento Cardíaco/diagnóstico , Neoplasias del Mediastino/complicaciones , Derrame Pericárdico/etiología , Derrame Pericárdico/cirugía , Técnicas de Ventana Pericárdica , Esternón , Adulto , Anciano , Anciano de 80 o más Años , Taponamiento Cardíaco/etiología , Diafragma , Drenaje , Femenino , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Derrame Pericárdico/complicaciones , Derrame Pericárdico/diagnóstico , Cirugía Torácica Asistida por Video , Toracotomía , Resultado del Tratamiento
11.
Melanoma Res ; 21(1): 12-23, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21102359

RESUMEN

Experiments were performed to explore differences between cultured primary and metastatic melanoma cell lines in their muscarinic acetylcholine receptor-mediated intracellular Ca signalization. The expression of type 1 and type 3 muscarinic receptors was detected and compared at the protein level using both immunocytochemistry and semiquantitative western blotting. The functionality of muscarinic receptors was tested by applying carbamylcholine (CCh; 1 mmol/l) and by recording the associated increases in cytoplasmic Ca using Ca imaging with the application of the Ca indicator dye, fluo-4. These data indicate that the expression levels of the receptor proteins were not significantly different in the metastatic (HT199, HT168-M1) and the primary (WM35) cell lines. Although Ca transients were evoked in all the three cell lines by CCh, the proportion of the CCh-positive cells was smaller amongst the WM35 cells. The Ca transients could be effectively blocked by atropine (0.1 mmol/l). The time courses of the Ca transients were highly variable, and in some instances they showed a late (plateau-like) component whose presence crucially depended on the influx of extracellular Ca. When the extracellular Ca concentration was reduced, the duration of the CCh-evoked transients was considerably decreased; a phenomenon that was more pronounced in the metastatic cell lines. Although there are no fundamental differences in the muscarinic receptor-mediated Ca signalization of the primary and metastatic cell lines, the quantitative differences showed in this study may partially explain the increased malignancy and migratory potential of the metastatic cells.


Asunto(s)
Calcio/metabolismo , Citoplasma/metabolismo , Melanoma/metabolismo , Receptores Muscarínicos/metabolismo , Neoplasias Cutáneas/metabolismo , Compuestos de Anilina/química , Atropina/química , Carbacol/química , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Humanos , Metástasis de la Neoplasia , Transducción de Señal , Xantenos/química , Melanoma Cutáneo Maligno
12.
Brain Res ; 1297: 57-69, 2009 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-19699723

RESUMEN

Purkinje-like cells (PLCs) of the cochlear nucleus (CN) are strongly calbindin positive neurones with unknown function. In the present work functional and morphological methods have been employed to provide data about PLCs in general, and about their possible involvement in the synaptic organisation of the CN in particular. PLCs had slightly elongated soma, from which a complex dendritic arborisation extended with highly variable dimensions. On the basis of their morphology, three classes of PLCs were identified. Positively identified PLCs fired a train of action potentials on sustained depolarization. When hyperpolarizing stimuli were applied, the presence of a slowly activating, ZD7288-sensitive inward current was noted that corresponded to the h-current. PLCs received both excitatory and inhibitory synaptic inputs. Functional experiments revealed that 76% and 14% of the spontaneous inhibitory postsynaptic currents recorded from the cell bodies of the PLCs were mediated via glycinergic and GABAergic synapses, respectively. PLCs presented strong cerebellin1-like immunoreactivity, but its distribution differed from that seen in cerebellar Purkinje cells. Our results indicate that PLCs are parts of the synaptic circuitry of the CN, thus they may be actively involved in the processing and analysis of auditory information.


Asunto(s)
Vías Auditivas/citología , Vías Auditivas/metabolismo , Núcleo Coclear/citología , Núcleo Coclear/metabolismo , Neuronas/citología , Neuronas/metabolismo , Potenciales de Acción/fisiología , Animales , Percepción Auditiva , Calbindinas , Forma de la Célula/fisiología , Dendritas/ultraestructura , Estimulación Eléctrica , Potenciales Postsinápticos Excitadores/fisiología , Femenino , Técnica del Anticuerpo Fluorescente , Glutamato Descarboxilasa/metabolismo , Glicina/metabolismo , Potenciales Postsinápticos Inhibidores/fisiología , Masculino , Proteínas del Tejido Nervioso/metabolismo , Técnicas de Cultivo de Órganos , Técnicas de Placa-Clamp , Células de Purkinje/citología , Ratas , Ratas Wistar , Proteína G de Unión al Calcio S100/metabolismo , Coloración y Etiquetado , Transmisión Sináptica/fisiología , Ácido gamma-Aminobutírico/metabolismo
13.
Hear Res ; 255(1-2): 73-83, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19497356

RESUMEN

The involvement of astrocytes in the cholinergic modulation of the cochlear nucleus has been studied using primary astrocyte cultures prepared from this nucleus. The cells were loaded with the membrane permeable form of the fluorescent Ca(2+) indicator Fluo-4, and carbachol-induced Ca(2+) concentration increases were monitored using an imaging system. In the presence of cholinergic stimulation 36.3% of the cells produced Ca(2+) transients. The time course of the transients was variable; 45.0% of the responding cells showed only a rapid Ca(2+) concentration increase, while in 50.5% of the astrocytes the fast component was followed by a slow plateau phase. Using muscarine as well as general and more specific cholinergic antagonists (atropine, pirenzepine, 4-DAMP and hexamethonium), the role of the M3 and (to a smaller extent) M1 muscarinic acetylcholine receptors could be demonstrated in the genesis of the carbachol-induced Ca(2+) transients. The presence of these two subtypes of muscarinic receptors has been confirmed at both mRNA (Q-PCR) and protein (immunocytochemistry) levels. Our data demonstrate the responsiveness of the cochlear astrocytes towards cholinergic stimulation, suggesting that they may have roles in mediating the effects of cholinergic modulation in the rat cochlear nucleus.


Asunto(s)
Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Señalización del Calcio/efectos de los fármacos , Agonistas Colinérgicos/farmacología , Núcleo Coclear/efectos de los fármacos , Núcleo Coclear/metabolismo , Animales , Calcio/metabolismo , Señalización del Calcio/fisiología , Carbacol/farmacología , Células Cultivadas , Antagonistas Colinérgicos/farmacología , Núcleo Coclear/citología , Citoplasma/metabolismo , Inmunohistoquímica , Reacción en Cadena de la Polimerasa , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Receptor Muscarínico M1/agonistas , Receptor Muscarínico M1/antagonistas & inhibidores , Receptor Muscarínico M1/genética , Receptor Muscarínico M1/metabolismo , Receptor Muscarínico M3/agonistas , Receptor Muscarínico M3/antagonistas & inhibidores , Receptor Muscarínico M3/genética , Receptor Muscarínico M3/metabolismo
14.
Pflugers Arch ; 457(6): 1303-25, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18777041

RESUMEN

The spiral ganglion cells provide the afferent innervation of the hair cells of the organ of Corti. Ninety-five percent of these cells (termed type I spiral ganglion neurones) are in synaptic contact with the inner hair cells, whereas about 5% of them are type II cells, which are responsible for the sensory innervation of the outer hair cells. To understand the function of the spiral ganglion neurones, it is important to explore their membrane properties, understand their activity patterns and describe the variety of ionic channels determining their behaviour. In this review, a brief description is given of the various experimental methods that allow the investigation of the spiral ganglion cells, followed by the discussion of their action potential firing patterns and ionic conductances. The presence, distribution and significance of the K(+) currents of the spiral ganglion cells are specifically addressed, along with the introduction of the putative subunit compositions of the relevant voltage-gated K(+) channels.


Asunto(s)
Canales de Potasio/fisiología , Ganglio Espiral de la Cóclea/fisiología , Potenciales de Acción/fisiología , Envejecimiento , Animales , Factor Neurotrófico Derivado del Encéfalo/farmacología , Canales de Calcio/metabolismo , Células Cultivadas , Venenos Elapídicos/farmacología , Técnicas Histológicas , Humanos , Factores de Crecimiento Nervioso/farmacología , Neuronas/fisiología , Órgano Espiral/citología , Potasio/metabolismo , Canales de Potasio/efectos de los fármacos , Canales de Sodio/metabolismo , Ganglio Espiral de la Cóclea/anatomía & histología
15.
Brain Res ; 1210: 148-62, 2008 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-18410910

RESUMEN

The spiral ganglion accommodates the cell bodies of the acoustic nerve fibres connecting the hair cells to the central nervous system. As the ionic channels containing various voltage-gated K+ channel (Kv) subunits play pivotal roles in determining the functional properties and firing behaviour of the spiral ganglion cells (SGCs), every piece of information concerning the Kv expression of the SGCs is valuable. In the present work a comprehensive immunohistochemical analysis was performed to describe the expression of 9 Kv subunits in the guinea pig cochlea on traditional wax-embedded sections as well as employing a newly developed preparation that allowed confocal analysis, reconstruction of the three-dimensional appearance and precise morphological characterisation of the SGCs. Besides determining their Kv expression patterns, differences between type I and type II SGCs were sought. SGCs showed positivity for 8 out of the 9 Kv subunit-specific antibodies with varying intensity and proportion of the immunopositive cells; whereas no obvious Kv3.2 positivity could be noted. Type I and type II cells demonstrated similar expression patterns for all subunits tested, with the exception of Kv1.2, whose presence was confirmed in only 50% of the type II cells. Although the present findings suggest that type I and type II cells do not differ fundamentally in the Kv subunits they possess; they also imply that SGCs may not form a homogeneous cell population, and might provide explanation of the previously noted heterogeneity of the membrane properties of the SGCs.


Asunto(s)
Cóclea/metabolismo , Neuronas Aferentes/metabolismo , Canales de Potasio con Entrada de Voltaje/metabolismo , Ganglio Espiral de la Cóclea/metabolismo , Animales , Membrana Celular/metabolismo , Tamaño de la Célula , Cóclea/citología , Disección/métodos , Cobayas , Citometría de Imagen , Masculino , Potenciales de la Membrana/fisiología , Microscopía Confocal/métodos , Microtomía/métodos , Neuronas Aferentes/clasificación , Neuronas Aferentes/citología , Técnicas de Cultivo de Órganos , Subunidades de Proteína/metabolismo , Ganglio Espiral de la Cóclea/citología
16.
J Histochem Cytochem ; 56(5): 443-65, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18256021

RESUMEN

Because the neuronal membrane properties and firing characteristics are crucially affected by the depolarization-activated K(+) channel (Kv) subunits, data about the Kv distribution may provide useful information regarding the functionality of the neurons situated in the cochlear nucleus (CN). Using immunohistochemistry in free-floating slices, the distribution of seven Kv subunits was described in the rat CN. Positive labeling was observed for Kv1.1, 1.2, 1.6, 3.1, 3.4, 4.2, and 4.3 subunits. Giant and octopus neurons showed particularly strong immunopositivity for Kv3.1; octopus neurons showed intense Kv1.1- and 1.2-specific reactions also. In the latter case, an age-dependent change of the expression pattern was also documented; although both young and older animals produced definite labeling for Kv1.2, the intensity of the reaction increased in older animals and was accompanied with the translocation of the Kv1.2 subunits to the cell surface membrane. The granule cell layer exhibited strong Kv4.2-specific immunopositivity, and markedly Kv4.2-positive glomerular synapses were also seen. It was found that neither giant nor pyramidal cells were uniform in terms of their Kv expression patterns. Our data provide new information about the Kv expression of the CN and also suggest potential functional heterogeneity of the giant and pyramidal cells.


Asunto(s)
Núcleo Coclear/metabolismo , Regulación de la Expresión Génica , Canales de Potasio con Entrada de Voltaje/metabolismo , Subunidades de Proteína/metabolismo , Animales , Especificidad de Anticuerpos , Núcleo Coclear/inmunología , Femenino , Inmunohistoquímica , Masculino , Microscopía Confocal , Canales de Potasio con Entrada de Voltaje/inmunología , Subunidades de Proteína/inmunología , Ratas , Ratas Wistar , Coloración y Etiquetado
17.
Virchows Arch ; 452(4): 415-26, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18094996

RESUMEN

The presence of TASK-3 channels has been described in a number of healthy and malignantly transformed cells, showing mainly intracellular distribution with relatively insignificant labelling of the cell surface membrane. In this work, immunochemical and molecular biology methods were utilised to establish the intracellular organelle whose TASK-3 expression accounts for this strong intracellular labelling using cultured melanoma and HaCaT cells. Before the immunocytochemical experiments, the presence of TASK-3 mRNA was also confirmed in melanoma cells. Comparison of the results of the TASK-3- and mitochondrion-specific labelling indicated that the TASK-3 channel subunits were strongly expressed by mitochondria in both investigated cell types. Moreover, prominent TASK-3 expression of keratinocytes could also be demonstrated in histological sections excised from the human skin. These results indicate that TASK-3 channels are present in the mitochondria in both malignantly transformed and healthy cells, suggesting that they might have roles in ensuring mitochondrial functions.


Asunto(s)
Queratinocitos/metabolismo , Melanoma/metabolismo , Mitocondrias/metabolismo , Canales de Potasio de Dominio Poro en Tándem/metabolismo , Neoplasias Cutáneas/metabolismo , Animales , Línea Celular , Línea Celular Tumoral , Regulación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Queratinocitos/citología , Melanoma/patología , Ratones , Mioblastos Esqueléticos/citología , Mioblastos Esqueléticos/metabolismo , ARN Mensajero/metabolismo , Neoplasias Cutáneas/patología , Transfección
18.
Magy Seb ; 60(2): 79-86, 2007 Apr.
Artículo en Húngaro | MEDLINE | ID: mdl-17649848

RESUMEN

Nowadays the management strategy for primary gastric lymphoma is undergoing change due to the effectiveness of chemotherapy and immunotherapy. While earlier surgical resection was the primary treatment and chemotherapy was only a follow-on procedure, at the present time this arrangement seems to have been reversed. Early stage low-grade MALT lymphoma can be treated with Helicobacter pylori eradication. Total or subtotal gastrectomy with D2 lymphadenectomy and with adjuvant chemotherapy in R1 situation is proposed up to stage II.1. The strategy is similar in the case of high-grade gastric lymphoma, but resection is useful only in those cases when one can be assured the result will be an R0 situation. With the exception of these cases, the only indication for resection is chemo-resistance. There is no reason for operating in advanced stages of the disease. The only purpose can be to manage complications. Unfortunately, the exact diagnosis is difficult. The diagnosis of lymphoma can often only be made after the operation. In the 6-year period between 1st January 2000 and 31st December 2005 we treated 38 patients for primary gastric lymphoma. Altogether 9 patients were operated on. Resection was performed in 6 cases. The diagnosis of lymphoma was known preoperatively only in one case. Nowadays surgery seems to be only secondary to chemotherapy and immuno-chemotherapy in the treatment of primary gastric MALT lymphoma. Our own cases also mirror this change.


Asunto(s)
Antibacterianos/uso terapéutico , Antineoplásicos/uso terapéutico , Gastrectomía , Inmunoterapia , Linfoma no Hodgkin/terapia , Neoplasias Gástricas/terapia , Adulto , Anciano , Quimioterapia Adyuvante , Terapia Combinada , Femenino , Gastrectomía/métodos , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori/efectos de los fármacos , Humanos , Escisión del Ganglio Linfático , Linfoma de Células B de la Zona Marginal/microbiología , Linfoma de Células B de la Zona Marginal/terapia , Linfoma no Hodgkin/diagnóstico , Linfoma no Hodgkin/microbiología , Linfoma no Hodgkin/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Retrospectivos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/microbiología , Neoplasias Gástricas/patología
19.
Brain Res Bull ; 71(5): 529-38, 2007 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-17259023

RESUMEN

Adequate interpretation of the functional data characterising the projection neurones of the cochlear nucleus (CN) is impossible without the unequivocal classification of these cell types at the end of the experiments. In this study, morphological criteria applicable for unambiguous identification of CN neurones have been sought. The neurones were labelled with rhodamine from incisions severing the projection pathways of the individual cell types, allowing their selective labelling and morphological characterisation. Confocal microscopy was employed for the investigation of the rhodamine-filled cells whose morphology was assessed after reconstructing the three-dimensional images of the cell bodies and proximal processes. The diameters of the somata and the number of processes originating from the cell bodies were also determined. In most of the cases, unambiguous identification of the bushy, octopus and Purkinje-like cells was relatively straightforward. On the other hand, precise classification of the pyramidal cells was often difficult, especially because giant cells could easily possess morphological features resembling pyramidal neurones. Occasionally, giant cells also mimicked the appearance of octopus neurones, which may be another important source of identification error, especially as these two cell types are often situated close to each other in the CN. It is concluded that morphological criteria defined in the present work may be effectively applied for the unambiguous identification of the projection neurones of the CN, even following functional measurements, when the correct cell classification is essential for the interpretation of the experimental data. Moreover, the present study also confirmed that Purkinje-like cells project to the cerebellum.


Asunto(s)
Núcleo Coclear/citología , Microscopía Confocal , Neuronas/citología , Rodaminas/metabolismo , Animales , Recuento de Células/métodos , Aumento de la Célula , Femenino , Inmunohistoquímica/métodos , Masculino , Neuronas/clasificación , Neuronas/metabolismo , Ratas , Ratas Wistar
20.
Peptides ; 27(7): 1717-25, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16500727

RESUMEN

The antifungal protein AFP is a small, cystein-rich protein secreted by the imperfect ascomycete Aspergillus giganteus. The protein efficiently inhibits the growth of filamentous fungi, including a variety of serious human and plant pathogens mainly of the genera Aspergillus and Fusarium, whereas AFP does not affect the growth of yeast and bacteria. This restricted susceptibility range makes it very attractive for medical or biotechnological use to combat fungal infection and contamination. We, therefore, analyzed whether AFP affects the growth or function of a number of mammalian cells. Here we show that the protein neither provokes any cytotoxic effects on human endothelial cells isolated from the umbilical vein nor activates the immune system. Moreover, potassium currents of neurons and astrocytes do not change in the presence of AFP and neither excitatory processes nor the intracellular calcium homeostasis of cultured skeletal muscle myotubes are affected by AFP. Our data, therefore, suggest that AFP is indeed a promising candidate for the therapeutic or biotechnological use as a potential antifungal agent.


Asunto(s)
Antifúngicos/farmacología , Aspergillus/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/fisiología , Animales , Astrocitos/metabolismo , Células Cultivadas , Endotelio Vascular/citología , Hipocampo/metabolismo , Humanos , Sistema Inmunológico , Músculo Esquelético/metabolismo , Neuronas/metabolismo , Potasio/química , Ratas , Ratas Wistar
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...