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1.
Fish Shellfish Immunol ; 105: 8-15, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32629105

RESUMEN

The immune response of teleosts (bonefish) is altered by diazinon (DZN), an organophosphate pesticide. It has been suggested that such alteration is due to the extraneuronal cholinergic system in fish leukocytes that renders these cells a target of pesticides. Diazoxon (DZO), the oxon metabolite of DZN, has been attributed immunotoxic effects. Still, to date there are no reports on the effects of DZO upon parameters involved in the signaling cascade of immune response cells. Therefore, this work evaluated the effect of DZO on key parameters of cell signaling (intracellular Ca2+ flux, ERK 1/2 phosphorylation), cell proliferation, and antiproliferative processes (apoptosis, senescence, mitochondrial membrane potential) in spleen mononuclear cells of Nile tilapia fish. The results obtained show that DZO does not affect cell proliferation but causes a lack of response to stimulation with PMA and ionomycin to release intracellular calcium. In addition, it inhibits ERK 1/2 phosphorylation and causes loss of mitochondrial membrane potential, apoptosis, and senescence. These results suggest that the lack of cell response to release intracytoplasmic Ca2+ inhibits ERK which disrupts the mitochondrial membrane potential, leading to cell apoptosis and senescence. These findings prove that DZO significantly affects key parameters involved in the survival of immune response cells.


Asunto(s)
Muerte Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Cíclidos/inmunología , Insecticidas/toxicidad , Leucocitos Mononucleares/efectos de los fármacos , Compuestos Organofosforados/toxicidad , Transducción de Señal/efectos de los fármacos , Animales , Diazinón/metabolismo , Insecticidas/metabolismo , Masculino
2.
Mol Biol Rep ; 46(2): 1593-1601, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30707416

RESUMEN

Ovalbumin is considered a protein of high nutritional value because it contains essential amino acids and is highly digestible. Therefore, it has a high biological value. Currently, the high food demand requires worldwide attention because food production is insufficient. Therefore, other alternatives are necessary to satisfy food demands, such as protein engineering. In this work, a protein with a high essential amino acid content similar to ovalbumin was synthesized by protein engineering, expressed, and digested in vitro. The assembly and sequential overlap extension PCR strategy was used to synthesize a 345-bp gene that encodes a high essential amino acid content protein (HEAAP). The 345-bp product was cloned into the vector pBAD TOPO®, and expressed in Escherichia coli BL21. PCR reactions and sequencing demonstrated the presence, orientation, and correct sequence of the insert. HEAAP expression was induced by L-arabinose and then purified using Ni-NTA affinity chromatography. The expression in E. coli was low and barely detected by Western blot assay. The in vitro multienzyme digestibility of HEAAP was around 79%, which suggests that the protein is potentially nutritious. Virtual analysis classifies the protein as unstable and hydrophilic, with a half-life in E. coli of 10 h. The recombinant HEAAP was successfully synthesized, but it is necessary to improve the digestibility and to optimize expression including selecting other expression models.


Asunto(s)
Ingeniería de Proteínas/métodos , Proteínas Recombinantes/síntesis química , Proteínas Recombinantes/aislamiento & purificación , Aminoácidos Esenciales/síntesis química , Aminoácidos Esenciales/fisiología , Cromatografía de Afinidad , Clonación Molecular/métodos , Suplementos Dietéticos , Escherichia coli/genética , Reacción en Cadena de la Polimerasa/métodos , Proteínas/síntesis química , Proteínas/aislamiento & purificación , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes/genética
3.
J Anim Physiol Anim Nutr (Berl) ; 101(2): 267-274, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27561464

RESUMEN

Undernutrition induces an increase of the oxidative stress that can predispose offspring to various diseases in adulthood through epigenetic reprogramming. The aim of this study was to evaluate the effects of intergenerational undernutrition on protein oxidation and antioxidant defence response on liver, heart and brain of the second-generation neonates (F2 ) of undernourished rats. For this purpose, both parents in parental (F0 ) and first generation (F1 ) were fed with a low-nutrient diet. Body mass and length decreased (p < 0.05) in F0 , F1 and F2 being the F1 males who exhibited a greater mass loss. A decrease in plasma albumin concentration was observed in F2 neonates (p < 0.05) and also a mass loss of liver, heart and brain (p < 0.05), although proportionally to body length reduction. Undernutrition increased levels of protein oxidation in liver and heart (p < 0.05) but not in brain (p > 0.05) while catalase activity increased only in brain (p < 0.05). In summary, intergenerational undernutrition modifies the antioxidant status through an organ-specific response, on F2 neonate rats, where the brain increased catalase activity to prevent a severe oxidative damage and support the vital functions of this key organ to maintain vital functions.


Asunto(s)
Animales Recién Nacidos , Desarrollo Fetal/fisiología , Trastornos Nutricionales en el Feto/fisiopatología , Desnutrición , Fenómenos Fisiologicos de la Nutrición Prenatal/fisiología , Animales , Peso Corporal , Femenino , Masculino , Estrés Oxidativo , Embarazo , Ratas , Ratas Wistar
4.
Neurobiol Dis ; 89: 88-100, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26852950

RESUMEN

The pathophysiology of Parkinson's disease (PD) and of L-DOPA-induced dyskinesia (LID) is associated with dysfunctional neuronal activity in several nuclei of the basal ganglia. Moreover, high levels of oscillatory activity and synchronization have also been described in both intra- and inter-basal ganglia nuclei and the cerebral cortex. However, the relevance of these alterations in the motor symptomatology related to Parkinsonism and LID is not fully understood. Recently, we have shown that subthalamic neuronal activity correlates with axial abnormal movements and that a subthalamic nucleus (STN) lesion partially reduces LID severity as well as the expression of some striatal molecular modifications. The aim of the present study was to assess, through single-unit extracellular recording techniques under urethane anaesthesia, neuronal activity of the substantia nigra pars reticulata (SNr) and its relationship with LID and STN hyperactivity together with oscillatory and synchronization between these nuclei and the cerebral cortex in 6-OHDA-lesioned and dyskinetic rats. Twenty-four hours after the last injection of L-DOPA the firing rate and the inhibitory response to an acute challenge of L-DOPA of SNr neurons from dyskinetic animals were increased with respect to those found in intact and 6-OHDA-lesioned rats. Moreover, there was a significant correlation between the mean firing rate of SNr neurons and the severity of the abnormal movements (limb and orolingual subtypes). There was also a significant correlation between the firing activity of SNr and STN neurons recorded from dyskinetic rats. In addition, low frequency band oscillatory activity and synchronization both within the SNr or STN and with the cerebral cortex were enhanced in 6-OHDA-lesioned animals and not or slightly affected by chronic treatment with L-DOPA. Altogether, these results indicate that neuronal SNr firing activity is relevant in dyskinesia and may be driven by STN hyperactivity. Conversely, low frequency oscillatory activity and synchronization seem to be more important in PD because they are not influenced by prolonged L-DOPA administration.


Asunto(s)
Potenciales de Acción/efectos de los fármacos , Ondas Encefálicas/efectos de los fármacos , Encéfalo/fisiopatología , Discinesia Inducida por Medicamentos/fisiopatología , Levodopa/administración & dosificación , Neuronas/fisiología , Trastornos Parkinsonianos/fisiopatología , Animales , Encéfalo/efectos de los fármacos , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/fisiopatología , Modelos Animales de Enfermedad , Neuronas GABAérgicas/efectos de los fármacos , Neuronas GABAérgicas/fisiología , Neuronas/efectos de los fármacos , Oxidopamina/administración & dosificación , Trastornos Parkinsonianos/inducido químicamente , Porción Reticular de la Sustancia Negra/efectos de los fármacos , Porción Reticular de la Sustancia Negra/fisiopatología , Ratas , Ratas Sprague-Dawley , Núcleo Subtalámico/efectos de los fármacos , Núcleo Subtalámico/fisiopatología
5.
Actas Urol Esp (Engl Ed) ; 48(4): 289-294, 2024 May.
Artículo en Inglés, Español | MEDLINE | ID: mdl-38159803

RESUMEN

INTRODUCTION: Patient satisfaction is the degree of conformity with the healthcare they receive. It is real evidence and one of the most important factors in determining the effectiveness and quality of healthcare systems. OBJECTIVE: To identify the quality of care in the Urology outpatient department of a third-level hospital. MATERIALS AND METHODS: The NHS (National Health Service) 2018 quality of care questionnaire with 11 sections, 133 items, and duration of approximately 25min was randomly administered to 250 patients attending Urology outpatients at a third-level public hospital in Mexico. RESULTS: According to responses, 92% (n=230) knew the reason for the consultation. 64.8% (n=162) had a consultation with the same physician by whom they were initially seen. The longest reported hospital wait time before being seen was more than 2h in 29.6% (n=74). As for consultation time, 212 patients responded and the duration was 11-20min in 52.8% (n=112). Finally, 33.2% (n=83) considered the quality of service to be good. CONCLUSIONS: The use of the NHS 2018 survey in the Urology service at a third-level public hospital in Mexico is feasible, since we managed to obtain a significant and continuous improvement in all its indicators which is satisfactory for all.


Asunto(s)
Hospitales Públicos , Satisfacción del Paciente , Calidad de la Atención de Salud , Derivación y Consulta , Urología , México , Humanos , Masculino , Persona de Mediana Edad , Femenino , Adulto , Derivación y Consulta/estadística & datos numéricos , Centros de Atención Terciaria , Anciano , Adulto Joven , Adolescente
6.
Science ; 374(6569): 848-856, 2021 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-34762454

RESUMEN

The signaling of cells by scaffolds of synthetic molecules that mimic proteins is known to be effective in the regeneration of tissues. Here, we describe peptide amphiphile supramolecular polymers containing two distinct signals and test them in a mouse model of severe spinal cord injury. One signal activates the transmembrane receptor ß1-integrin and a second one activates the basic fibroblast growth factor 2 receptor. By mutating the peptide sequence of the amphiphilic monomers in nonbioactive domains, we intensified the motions of molecules within scaffold fibrils. This resulted in notable differences in vascular growth, axonal regeneration, myelination, survival of motor neurons, reduced gliosis, and functional recovery. We hypothesize that the signaling of cells by ensembles of molecules could be optimized by tuning their internal motions.


Asunto(s)
Nanofibras , Péptidos , Traumatismos de la Médula Espinal/terapia , Regeneración de la Medula Espinal , Andamios del Tejido , Animales , Supervivencia Celular , Simulación por Computador , Células Endoteliales de la Vena Umbilical Humana/fisiología , Humanos , Integrina beta1/metabolismo , Laminina/química , Laminina/metabolismo , Ratones , Neuronas Motoras/fisiología , Neovascularización Fisiológica , Células-Madre Neurales/fisiología , Péptidos/química , Peptidomiméticos/química , Polímeros/química , Conformación Proteica en Lámina beta , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/metabolismo , Recuperación de la Función , Transducción de Señal , Tensoactivos
7.
Rev Neurol ; 73(9): 299-306, 2021 11 01.
Artículo en Español | MEDLINE | ID: mdl-34676527

RESUMEN

INTRODUCTION: There is a growing interest in the study of the relationship between heart disease, including acute coronary syndrome (ACS) and cognitive impairment, and although the factors mediating ACS and cognitive impairment are not well understood, the debate revolves around the role of the left ventricular ejection fraction (LVEF). AIMS: To determine the presence of cognitive impairment in patients with ACS and explore its association with various factors, including sociodemographic, medication use and performance on cardiac function tests (in particular LVEF). PATIENTS AND METHODS: Sociodemographic, medical and neuropsychological variables were collected in 80 patients with ACS participating in a cardiac rehabilitation programme. Their scores on the neuropsychological battery were compared with normative population data to determine which subjects showed deficient performance. Regression analyses were conducted to determine which factors are associated with performance on neuropsychological tests. RESULTS: Compared to their normative group, 37.5% of the subjects had low scores on three or more neuropsychological tests. Age, low educational level and low LVEF explained up to 51% of the variability in neuropsychological test results. CONCLUSIONS: Patients with ACS are more likely to have impaired cognitive functions, such as attention, memory and executive functions, along with a slower information processing speed. An LVEF below 50% could be a major explanatory factor for such cognitive impairment.


TITLE: Variabilidad en el rendimiento neuropsicológico en pacientes con síndrome coronario agudo.Introducción. Existe un interés creciente por el estudio de la relación entre las cardiopatías, incluido el síndrome coronario agudo (SCA) y el deterioro cognitivo, y, aunque no se conocen con concreción los factores que median entre el SCA y el deterioro cognitivo, en el centro de este debate se encuentra el papel de la fracción de eyección del ventrículo izquierdo (FEVI). Objetivos. Determinar la presencia de deterioro cognitivo en pacientes con SCA y explorar su asociación con diversos factores ­sociodemográficos, consumo de fármacos, rendimiento en pruebas funcionales cardíacas (en particular, la FEVI)­. Pacientes y métodos. Se recogieron variables sociodemográficas, médicas y neuropsicológicas en 80 pacientes con SCA que participaban en un programa de rehabilitación cardíaca. Se compararon sus puntuaciones en la batería neuropsicológica con los datos normativos poblacionales para determinar qué sujetos mostraban un rendimiento deficitario. Se realizaron análisis de regresión para determinar qué factores se asocian con el rendimiento en las pruebas neuropsicológicas. Resultados. En comparación con su grupo normativo, el 37,5% de los sujetos presentó una baja puntuación en tres o más test neuropsicológicos. La edad, un bajo nivel educativo y una FEVI baja explicaron hasta el 51% de la variabilidad en los resultados de las pruebas neuropsicológicas. Conclusiones. Los pacientes con SCA tienen más posibilidades de presentar un deterioro de funciones cognitivas, como la atención, la memoria y las funciones ejecutivas, junto con un enlentecimiento en la velocidad de procesamiento de la información. Una FEVI inferior al 50% podría ser un factor explicativo destacado de dicho deterioro cognitivo.


Asunto(s)
Síndrome Coronario Agudo/complicaciones , Síndrome Coronario Agudo/psicología , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/etiología , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas
8.
ISA Trans ; 97: 76-85, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31350047

RESUMEN

Classical methods for monitoring electromechanical systems lack two critical functions for effective industrial application: management of unexpected events and the incorporation of new patterns into the knowledge database. This study presents a novel, high-performance condition-monitoring method based on a four-stage incremental learning approach. First, non-stationary operation is characterised using normalised time-frequency maps. Second, operating novelties are detected using multivariate kernel density estimators. Third, the operating novelties are characterised and labelled to increase the knowledge available for subsequent diagnosis. Fourth, operating faults are diagnosed and classified using neural networks. The proposed method is validated experimentally with an industrial camshaft-based machine under a variety of operating conditions.

9.
Eur Rev Med Pharmacol Sci ; 24(13): 7412-7419, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32706080

RESUMEN

OBJECTIVE: Vorinostat is a drug used to treat cutaneous T cell lymphoma whose action mechanism is based on Histone Deacetylase inhibition. Histone Deacetylases are a family of enzymes that remove acetyl groups from histone and non-histone proteins that control many crucial processes, such as gene regulation, cell cycle progression, differentiation, and apoptosis. Histone Deacetylase homologues are also expressed in parasites of the genus Plasmodium, Leishmania, Cryptosporidium, Schistosoma, Entamoeba, and others. In this way, antiparasitic properties of Vorinostat have been explored. The aim of this review is to report the current state knowledge of Vorinostat as antiparasitic drug against Plasmodium, Leishmania, Cryptosporidium, Schistosoma and Entamoeba in order to support future investigation in this field. MATERIALS AND METHODS: The authors revised the recent and relevant literature concerning the topic and discussed advances and limitations of studies on Vorinostat as potential drug to treat human parasitic diseases. RESULTS: Vorinostat has been efficient in vitro and, in some cases, in vivo, against parasites that cause parasitic diseases, such as malaria, leishmaniasis, cryptosporidiosis, amoebiasis, and schistosomiasis. CONCLUSIONS: In vitro and in vivo models have demonstrated the antiparasitic activity of Vorinostat, however, the challenge is to assay its activity in animal models and to evaluate if Vorinostat is safe for humans as new alternative to treat human parasitic infections.


Asunto(s)
Antiparasitarios/uso terapéutico , Inhibidores de Histona Desacetilasas/uso terapéutico , Histona Desacetilasas , Parásitos/efectos de los fármacos , Enfermedades Parasitarias/tratamiento farmacológico , Proteínas Protozoarias/antagonistas & inhibidores , Vorinostat/uso terapéutico , Animales , Antiparasitarios/efectos adversos , Reposicionamiento de Medicamentos , Inhibidores de Histona Desacetilasas/efectos adversos , Histona Desacetilasas/metabolismo , Interacciones Huésped-Parásitos , Humanos , Parásitos/enzimología , Parásitos/patogenicidad , Enfermedades Parasitarias/diagnóstico , Enfermedades Parasitarias/parasitología , Proteínas Protozoarias/metabolismo , Vorinostat/efectos adversos
10.
Science ; 195(4281): 894-7, 1977 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-841315

RESUMEN

Like horizontal cells in vertebrate retinas, horizontal amacrine cells beneath the insect eye intervene between receptors and interneurons at the first level of synapses. Synaptic arrangements between amacrines and interneurons that give rise to regular networks of axon collaterals may explain recent electrophysiological observations of lateral inhibition beneath the insect retina. Neural adaptation mechanisms acting on single retinotopic channels or assemblies of channels can also be referred to reciprocal relationships between receptors and first-order interneurons as well as to centrifugal cells from levels of so-called photopic receptor endings.


Asunto(s)
Moscas Domésticas/fisiología , Visión Ocular , Vías Visuales/fisiología , Adaptación Fisiológica , Animales , Interneuronas/citología , Microscopía Electrónica , Inhibición Neural , Células Fotorreceptoras/citología , Células Fotorreceptoras/fisiología , Epitelio Pigmentado Ocular/citología , Epitelio Pigmentado Ocular/fisiología , Sinapsis/ultraestructura , Vías Visuales/citología
11.
Exp Neurol ; 322: 113036, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31425688

RESUMEN

The pathophysiology of Parkinson's disease (PD) and L-DOPA-induced dyskinesia (LID) is associated with aberrant neuronal activity and abnormal high levels of oscillatory activity and synchronization in several basal ganglia nuclei and the cortex. Previously, we have shown that the firing activity of neurons in the substantia nigra pars reticulata (SNr) is relevant in dyskinesia and may be driven by subthalamic nucleus (STN) hyperactivity. Conversely, low frequency oscillatory activity and synchronization in these structures seem to be more important in PD because they are not influenced by prolonged L-DOPA administration. The aim of the present study was to assess (through single-unit extracellular recording techniques under urethane anaesthesia) the neuronal activity of the entopeduncular nucleus (EPN) and its relationship with LID and STN hyperactivity, together with the oscillatory activity and synchronization between these nuclei and the cerebral cortex in 6-OHDA-lesioned rats that received long term L-DOPA treatment (or not). Twenty-four hours after the last L-DOPA injection the firing activity of EPN neurons in long term L-DOPA treated 6-OHDA-lesioned rats was more irregular and bursting compared to sham rats, being those alterations partially reversed by the acute challenge of L-DOPA. No correlation between EPN neurons firing activity and abnormal involuntary movements score was found. However, there was a significant correlation between the firing activity parameters of EPN and STN neurons recorded from long term L-DOPA treated 6-OHDA-lesioned rats. Low frequency oscillatory activity and synchronization both within the EPN and with the cerebral cortex were enhanced in 6-OHDA-lesioned animals. These changes were reversed by the acute L-DOPA challenge only in long term L-DOPA treated 6-OHDA-lesioned rats. Altogether, these results obtained from long term L-DOPA treated 6-OHDA-lesioned rats suggest (1) a likely relationship between STN and EPN firing patterns and spiking phases induced by changes after prolonged L-DOPA administration and (2) that the effect of L-DOPA on the firing pattern, low frequency oscillatory activity and synchronization in the EPN may have a relevant role in LID.


Asunto(s)
Discinesia Inducida por Medicamentos/fisiopatología , Núcleo Entopeduncular/efectos de los fármacos , Núcleo Entopeduncular/fisiopatología , Levodopa/farmacología , Trastornos Parkinsonianos/fisiopatología , Adrenérgicos/toxicidad , Animales , Antiparkinsonianos/farmacología , Masculino , Neuronas/efectos de los fármacos , Oxidopamina/toxicidad , Trastornos Parkinsonianos/inducido químicamente , Ratas , Ratas Sprague-Dawley , Núcleo Subtalámico/efectos de los fármacos , Núcleo Subtalámico/fisiopatología
12.
J Neuroimmune Pharmacol ; 14(3): 413-422, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30649665

RESUMEN

Analysis of gut barrier status, monocyte and lymphocyte activation and T regulatory (Treg) cells at diagnosis before and after therapy, in patients with multiple sclerosis (MS). Analysis of differential effects of interferon beta (IFN-ß), glatiramer acetate (GA) and natalizumab. Thirty-five patients with untreated MS were included. Gut barrier status (serum concentrations of intestinal fatty acid binding protein), monocyte (serum levels of soluble CD14, soluble CD163 and interleukin 6) and T lymphocyte activation (CD4 + DR+ and CD8 + DR+) and Treg (CD4 + CD25highFoxP3+) cells were analyzed. Patients with clinical isolated syndrome and relapsing-remitting forms were treated with IFN-ß or GA, and immune characteristics were reevaluated following up after 6 months. A sample of 56 stable RR MS patients, in treatment with IFN-ß, GA or natalizumab, and 50 healthy individuals were included as controls. Gut barrier status was similar in MS patients and healthy controls. Untreated patients with relapsing-remitting and primary progressive patterns of MS showed increased serum levels of soluble CD14. At baseline, significant increases in activated T lymphocytes and Treg were detected in patients. A significant decrease of CD4 + DR+, CD8 + DR+, and Treg percentages after 6 months of therapy was observed. In previously treated patients, IFN-ß, GA, or natalizumab therapies were associated with a comparable cell proportion of activated lymphocytes and Treg. MS patients have a baseline state characterized by monocyte and lymphocyte activation, not related with gut barrier lesion. An increase in Treg number, correlated with activated T CD8+ lymphocytes, was detected. Treatment with IFN-ß, GA or natalizumab was associated with a comparable decrease in activated lymphocytes and Treg. Graphical Abstract ᅟ.


Asunto(s)
Acetato de Glatiramer/farmacología , Interferón beta/farmacología , Activación de Linfocitos/efectos de los fármacos , Monocitos/efectos de los fármacos , Esclerosis Múltiple Crónica Progresiva/tratamiento farmacológico , Esclerosis Múltiple Recurrente-Remitente/tratamiento farmacológico , Natalizumab/farmacología , Subgrupos de Linfocitos T/efectos de los fármacos , Adulto , Estudios de Casos y Controles , Proteínas de Unión a Ácidos Grasos/sangre , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Acetato de Glatiramer/uso terapéutico , Humanos , Interferón beta/uso terapéutico , Masculino , Persona de Mediana Edad , Monocitos/inmunología , Monocitos/metabolismo , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple Crónica Progresiva/inmunología , Esclerosis Múltiple Recurrente-Remitente/inmunología , FN-kappa B/metabolismo , Natalizumab/uso terapéutico , Proteínas del Tejido Nervioso/biosíntesis , Proteínas del Tejido Nervioso/genética , Estudios Prospectivos , Transducción de Señal/efectos de los fármacos , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo
13.
Neuron ; 16(2): 275-86, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8789943

RESUMEN

The segregation of neural and epidermal progenitors in Drosophila requires the activity of transcription factors encoded by the proneural genes and the genes of the E(SPL)-C. Persistent expression of two genes of the E(SPL)-C suppresses neural development. Embryos exhibit conspicuous central neural hypoplasia and lack sensory organs; imaginal sensory organs are also affected. Suppression of neural development is associated with suppression of the activity of proneural genes. DNA binding is not essential for this effect. Large cells with characteristics of neuroblasts segregate normally in embryos, but these cells fail to express various markers, and the segregated cells and/or their progeny eventually die. These findings indicate that proneural and E(spl) proteins exert antagonistic functions.


Asunto(s)
Drosophila/crecimiento & desarrollo , Drosophila/genética , Elementos de Facilitación Genéticos , Expresión Génica , Mutación , Sistema Nervioso/crecimiento & desarrollo , Animales , Muerte Celular , Desarrollo Embrionario y Fetal , Dosificación de Gen , Sistema Nervioso/embriología , Malformaciones del Sistema Nervioso
14.
Neuron ; 5(1): 81-9, 1990 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2114885

RESUMEN

Loss of function mutations in genes of the achaete-scute complex (ASC) or in the gene vnd of D. melanogaster result in neural hypoplasia. Two types of defects contribute to the development of the neural hypoplasic phenotype: a lower than normal proportion of neuroblasts delaminate from the neuroectoderm, and there is abundant cell death in the neural primordium during later stages. In addition, we found that increasing the copy number of ASC wild-type alleles leads to effects opposite to those caused by their deletion. All of these results indicate that the function of these genes is required for the commitment of neuroectodermal cells as neuroblasts and that the loss of these genetic functions causes the cells either to take on an epidermal fate or to die.


Asunto(s)
Drosophila melanogaster/genética , Genes , Mutación , Malformaciones del Sistema Nervioso , Animales , Supervivencia Celular , Drosophila melanogaster/embriología , Embrión no Mamífero/anatomía & histología , Sistema Nervioso/patología , Neuronas/patología , Fenotipo
15.
Neuron ; 9(5): 847-59, 1992 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1418999

RESUMEN

Notch locus EGF-like element mutations spl, altering eye development, and AxE2, affecting wing and sensilla development, are modified by mutations at Delta. It is shown that two allele-specific suppressors of spl involve single amino acid substitutions in the 4th (Dlsup5) and 9th (Dlsup4) EGF-like elements of the Delta protein. Cultured cells producing spl or AxE2 aggregate with cells producing wild-type Delta or Dlsup5 protein, and Dlsup5-producing cells adhere to cells producing wild-type Notch protein. However, spl,AxE2, and Dlsup5 are each defective in promoting these cell affinities, as none of the mutant proteins can compete with the corresponding wild-type proteins for formation of cell aggregates. Thus, widely separated EGF-like elements of Notch and Delta appear to participate in functional molecular interactions between the proteins. Dlsup5 does not improve adhesiveness of spl in vitro, so suppression in vivo may involve altered developmental signaling by spl-Dlsup5 complexes, rather than modified cell adhesion.


Asunto(s)
Drosophila melanogaster/genética , Factor de Crecimiento Epidérmico/química , Hormonas de Insectos/química , Proteínas de la Membrana/química , Mutagénesis , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Western Blotting , Adhesión Celular , Agregación Celular , Línea Celular Transformada , Proteínas de Drosophila , Drosophila melanogaster/crecimiento & desarrollo , Factor de Crecimiento Epidérmico/genética , Hormonas de Insectos/genética , Hormonas de Insectos/fisiología , Péptidos y Proteínas de Señalización Intracelular , Proteínas de la Membrana/genética , Proteínas de la Membrana/fisiología , Datos de Secuencia Molecular , Receptores Notch , Transfección
16.
Neuroscience ; 151(3): 817-23, 2008 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-18164823

RESUMEN

The cannabinoid CB1 receptor which is densely located in the basal ganglia is known to participate in the regulation of movement. The present study sought to determine the mechanisms underlying the effect of Delta(9)-tetrahydrocannabinol (Delta(9)-THC) on neurons in the substantia nigra pars compacta (SNpc) using single-unit extracellular recordings in anesthetized rats. Administration of Delta(9)-THC (0.25-2 mg/kg, i.v.) increased the firing rate of SNpc neurons (maximal effect: 33.54+/-6.90%, n=8) without modifying other firing parameters (coefficient of variation and burst firing). This effect was completely blocked by the cannabinoid receptor antagonist rimonabant (0.5 mg/kg, i.v.). In addition, the blockade of excitatory amino acids receptors by kynurenic acid (0.5 microM, i.c.v.) or a chemical lesion of the subthalamic nucleus (STN) with ibotenic acid abolished Delta(9)-THC effect. These results indicate that CB1 receptor activation modulates SNpc neuronal activity by an indirect mechanism involving excitatory amino acids, probably released from STN axon terminals in the SNpc.


Asunto(s)
Dopamina/metabolismo , Dronabinol/farmacología , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Psicotrópicos/farmacología , Núcleo Subtalámico/fisiología , Potenciales de Acción/efectos de los fármacos , Análisis de Varianza , Animales , Apomorfina/farmacología , Agonistas de Dopamina/farmacología , Relación Dosis-Respuesta a Droga , Agonistas de Aminoácidos Excitadores/efectos adversos , Ácido Iboténico/efectos adversos , Ácido Quinurénico/efectos adversos , Masculino , Piperidinas/farmacología , Pirazoles/farmacología , Ratas , Ratas Sprague-Dawley , Rimonabant , Sustancia Negra/citología , Núcleo Subtalámico/lesiones
17.
IEEE Trans Neural Netw ; 19(4): 723-5, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18390315

RESUMEN

During the usual SVM biclassification learning process, the bias is chosen a posteriori as the value halfway between separating hyperplanes. A note on different approaches on the calculation of the bias when SVM is used for multiclassification is provided and empirical experimentation is carried out which shows that the accuracy rate can be improved by using bias formulations, although no single formulation stands out as providing better performance.


Asunto(s)
Sesgo , Redes Neurales de la Computación , Análisis Numérico Asistido por Computador , Simulación por Computador , Humanos
18.
Medicine (Madr) ; 12(53): 3168-3173, 2018 Apr.
Artículo en Español | MEDLINE | ID: mdl-32287904

RESUMEN

In the elderly, pneumonia often has a less florid clinical presentation and is frequently complicated by decompensation of concomitant diseases. Elderly patients have special characteristics in terms of the pathogens involved in pneumonia; they are at greater risk of multiresistant bacterial infections because of their frequent contact with the health services. Lung infections in immunosuppressed individuals have different causes depending on the immune deficiency in question. Admission to hospital or ambulatory treatment will be decided after stratifying the risk; this treatment will be determined by the characteristics at the time of onset of the pneumonia, the local epidemiological situation in terms of the percentage of antibiotic resistance in the area, and the clinical particularities.

20.
Mol Neurobiol ; 55(1): 201-212, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28840516

RESUMEN

Neurotrophic factors (NTFs) are a promising therapeutic option for Parkinson's disease (PD). They exert their function through tyrosine kinase receptors. Our goal was to assess the effects of administering a selective tyrosine kinase inhibitor (vandetanib) that blocks VEGFR2 and RET receptors in a preclinical model of PD. Rats underwent intrastriatal injections of 6-hydroxydopamine (6-OHDA). Two weeks later, the rats received 30 mg/kg vandetanib or saline orally. The effects were assessed using the rotational behavioral test, tyrosine hydroxylase (TH) immunohistochemistry, and western blot. In 6-OHDA-lesioned rats, motor symptoms were almost undetectable, but morphological and biochemical changes were significant. Vandetanib treatment, combined with the presence of 6-OHDA lesions, significantly increased behavioral impairment and morphological and biochemical changes. Therefore, after vandetanib treatment, the TH-immunopositive striatal volume, the percentage of TH+ neurons, and the extent of the axodendritic network in the substantia nigra decreased. Glial fibrillary acidic protein-positivity significantly decreased in the striatum and substantia nigra in the vandetanib-treated group. In addition, p-Akt and p-ERK 1/2 levels were significantly lower and caspase-3 expression significantly increased after vandetanib administration. In conclusion, we demonstrate for the first time the deleterious effect of a tyrosine kinase inhibitor on the dopaminergic system, supporting the beneficial and synergistic effect of NTFs reported in previous papers.


Asunto(s)
Trastornos Parkinsonianos/metabolismo , Piperidinas/toxicidad , Proteínas Proto-Oncogénicas c-ret/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-ret/metabolismo , Quinazolinas/toxicidad , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Animales , Masculino , Trastornos Parkinsonianos/inducido químicamente , Trastornos Parkinsonianos/patología , Ratas , Ratas Sprague-Dawley , Resultado del Tratamiento
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