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1.
Mol Psychiatry ; 23(3): 691-700, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28696429

RESUMEN

Human mutations of the GRID1 gene encoding the orphan delta1 glutamate receptor-channel (GluD1) are associated with schizophrenia but the explicit role of GluD1 in brain circuits is unknown. Based on the known function of its paralog GluD2 in cerebellum, we searched for a role of GluD1 in slow glutamatergic transmission mediated by metabotropic receptor mGlu1 in midbrain dopamine neurons, whose dysfunction is a hallmark of schizophrenia. We found that an mGlu1 agonist elicits a slow depolarizing current in HEK cells co-expressing mGlu1 and GluD1, but not in cells expressing mGlu1 or GluD1 alone. This current is abolished by additional co-expression of a dominant-negative GluD1 dead pore mutant. We then characterized mGlu1-dependent currents in dopamine neurons from midbrain slices. Both the agonist-evoked and the slow postsynaptic currents are abolished by expression of the dominant-negative GluD1 mutant, pointing to the involvement of native GluD1 channels in these currents. Likewise, both mGlu1-dependent currents are suppressed in GRID1 knockout mice, which reportedly display endophenotypes relevant for schizophrenia. It is known that mGlu1 activation triggers the transition from tonic to burst firing of dopamine neurons, which signals salient stimuli and encodes reward prediction. In vivo recordings of dopamine neurons showed that their spontaneous burst firing is abolished in GRID1 knockout mice or upon targeted expression of the dominant-negative GluD1 mutant in wild-type mice. Our results de-orphanize GluD1, unravel its key role in slow glutamatergic transmission and provide insights into how GRID1 gene alterations can lead to dopaminergic dysfunctions in schizophrenia.


Asunto(s)
Neuronas Dopaminérgicas/metabolismo , Glutamato Deshidrogenasa/genética , Receptores de Glutamato/genética , Animales , Cerebelo/metabolismo , Dopamina/metabolismo , Neuronas Dopaminérgicas/fisiología , Glutamato Deshidrogenasa/fisiología , Células HEK293 , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores de Glutamato/fisiología , Receptores de Glutamato Metabotrópico/genética , Receptores de Glutamato Metabotrópico/metabolismo , Esquizofrenia/genética , Análisis de la Célula Individual
2.
BMC Pulm Med ; 16(1): 177, 2016 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-27931198

RESUMEN

BACKGROUND: Staging of mediastinal lymph nodes in non-small cell lung cancer (NSCLC) is mandatory. The maximum Standard Uptake Value (SUVmax) obtained using F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) is the best non-invasive technique available for this evaluation, but its performance varies from center to center. The aim of the present study was to identify FDG-PET predictors of mediastinal malignancy that are able to minimize intercenter variability and improve the selection of subsequent staging procedures. METHOD: A multicenter study of NSCLC patients staged through FDG-PET and endobronchial ultrasonography with needle aspiration (EBUS-NA) was performed using therapeutic surgery with systematic nodal dissection as gold standard. Intercenter variability and predictive power for mediastinal malignancy of different FDG-PET measures were assessed, as well as the role of these measures for selecting additional staging procedures. RESULTS: One hundred and twenty-one NSCLC patients, of whom 94 (72%) had ≥1 hypermetabolic spots in the mediastinum, were included in the study. Mean SUVmax of the primary tumor was 12.3 (SD 6.3), and median SUVmax of the highest hypermetabolic spots in the mediastinum was 3.9 (IQR 2.4-7). Variability of FDG-PET measures between hospitals was statistically significant (p = 0.016 and p < 0.001 respectively), but lost significance when SUVmax in the mediastinum was expressed as a ratio or a subtraction from the primary tumor (SUVmax mediastinum/tumor, p = 0.083; and SUVmax mediastinum - tumor, p = 0.428 respectively). SUVmax mediastinum/tumor showed higher accuracy in the ROC analysis (AUC 0.77 CI 0.68-0.85, p < 0.001), and showed predictive power for mediastinal malignancy when using a 0.4 cutoff (OR 6.62, 95%CI 2.98-14.69). Sensitivities and negative predictive values of clinical staging through EBUS-NA attained values ranging between 57% and 92% after FDG-PET, which improved with additional techniques when the tumor had a diameter >3 cm and/or a SUVmax mediastinum/tumor ratio >0.4. CONCLUSION: The SUVmax mediastinum/tumor ratio is a good predictor of regional tumor extension in NSCLC. This measure is not influenced by intercenter variability and has an accuracy of over 70% for the identification of malignancy when using a 0.4 cutoff.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/patología , Neoplasias del Mediastino/diagnóstico por imagen , Neoplasias del Mediastino/secundario , Tomografía de Emisión de Positrones , Anciano , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico , Femenino , Fluorodesoxiglucosa F18 , Humanos , Modelos Logísticos , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/patología , Masculino , Mediastino/diagnóstico por imagen , Mediastino/patología , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Prospectivos , Curva ROC , España
3.
J Infect ; 72(6): 738-744, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27025205

RESUMEN

BACKGROUND: The role of galactomannan (GM) in serum or bronchoalveolar lavage fluid (BALF) for the diagnosis of invasive pulmonary aspergillosis (IPA) has been extensively evaluated in hematological patients, however its performance in non-hematological patients is not well established. METHODS: We performed a multicenter retrospective study in 3 university hospitals in Madrid, Spain between 2010 and 2014. The study population comprised patients with chronic obstructive pulmonary disease (COPD) and patients with immunosuppressive conditions in whom IPA was suspected and for whom BALF GM was available. Patients with hematological disorders were excluded. RESULTS: A total of 188 patients (35 with COPD and 153 with immunosuppressive conditions) were analyzed, and 31 cases of IPA (proven or probable) were identified. The global sensitivity of BALF GM (optical density index [ODI] ≥ 1.0) was 77.4%; sensitivity was higher in patients with immunosuppressive conditions than in patients with COPD (81.8% vs 66.7%; p: 0.38). In COPD patients, the best performance was obtained for BALF GM (ODI ≥ 0.5), although sensitivity (88.9%) was similar to that of BALF fungal culture (88.9%). The sensitivity of GM in serum was very poor in both populations (36.4% and 11.6%, respectively). CONCLUSIONS: In the present series, the diagnostic performance of BALF GM was good for IPA in non-hematological patients, especially in patients with immunosuppressive conditions.


Asunto(s)
Líquido del Lavado Bronquioalveolar/química , Huésped Inmunocomprometido , Aspergilosis Pulmonar Invasiva/diagnóstico , Mananos/análisis , Adulto , Líquido del Lavado Bronquioalveolar/microbiología , Femenino , Galactosa/análogos & derivados , Humanos , Aspergilosis Pulmonar Invasiva/microbiología , Masculino , Mananos/química , Mananos/aislamiento & purificación , Persona de Mediana Edad , Neutropenia , Enfermedad Pulmonar Obstructiva Crónica , Estudios Retrospectivos , Sensibilidad y Especificidad , España , Adulto Joven
4.
Neuroscience ; 217: 67-76, 2012 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-22554781

RESUMEN

The firing properties of dopamine (DA) neurons in the substantia nigra (SN) pars compacta are strongly influenced by the activity of apamin-sensitive small conductance Ca(2+)-activated K(+) (SK) channels. Of the three SK channel genes expressed in central neurons, only SK3 expression has been identified in DA neurons. The present findings show that SK2 was also expressed in DA neurons. Immuno-electron microscopy (iEM) showed that SK2 was primarily expressed in the distal dendrites, while SK3 was heavily expressed in the soma and, to a lesser extent, throughout the dendritic arbor. Electrophysiological recordings of the effects of the SK channel blocker apamin on DA neurons from wild type and SK(-/-) mice show that SK2-containing channels contributed to the precision of action potential (AP) timing, while SK3-containing channels influenced AP frequency. The expression of SK2 in DA neurons may endow distinct signaling and subcellular localization to SK2-containing channels.


Asunto(s)
Potenciales de Acción/fisiología , Neuronas Dopaminérgicas/fisiología , Canales de Potasio de Pequeña Conductancia Activados por el Calcio/metabolismo , Potenciales de Acción/efectos de los fármacos , Animales , Apamina/farmacología , Neuronas Dopaminérgicas/efectos de los fármacos , Neuronas Dopaminérgicas/metabolismo , Ratones , Ratones Noqueados , Canales de Potasio de Pequeña Conductancia Activados por el Calcio/genética , Sustancia Negra/efectos de los fármacos , Sustancia Negra/metabolismo
5.
Ultrasound Med Biol ; 38(1): 62-8, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22137179

RESUMEN

The objective of our study was to determine the procedure-related requirements of mediastinal node sampling with endobronchial ultrasonography with real-time transbronchial needle aspiration (EBUS-TBNA) that would provide negative predictive value (NPV) for the identification of stage III disease in non-small-cell lung cancer (NSCLC) high enough to consider the technique equivalent to cervical mediastinoscopy. Representative EBUS-TBNA was defined as a sampling procedure obtaining satisfactory samples from normal nodes in regions 4R, 4L and 7 or diagnosing malignancy in mediastinal nodes. NPV was estimated using the results of postsurgical staging in patients who underwent surgery as a reference. Two-hundred ninety-six patients staged with EBUS-TBNA were included. Representative samples from regions 4R, 4L and 7 showing nonmalignant cytology were obtained from 98 patients (33.1%) and EBUS-TBNA detected N2/N3 disease in 150 (50.7%). Accordingly, an EBUS-TBNA procedure accomplishing the representativeness criteria required for sampling was attained in 248 of the participating patients (83.8%). The NPV of the procedure in this setting was 93.6%, with false-negative results only found in 5 patients, four of them with nodal metastasis out of the reach of EBUS-TBNA (regions 5, 8 and 9). In conclusion, representative sampling of regions 4R, 4L and 7 is achieved in more than 80% of patients staged using EBUS-TBNA, and in the procedures that attain this requirement a NPV >90% for mediastinal malignancy is reached, a figure equivalent to cervical mediastinoscopy.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/secundario , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/epidemiología , Ganglios Linfáticos/diagnóstico por imagen , Mediastino/diagnóstico por imagen , Ultrasonografía/estadística & datos numéricos , Carcinoma de Pulmón de Células no Pequeñas/epidemiología , Femenino , Humanos , Metástasis Linfática , Masculino , Estadificación de Neoplasias , Prevalencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , España/epidemiología
6.
Eur Respir J ; 37(1): 136-42, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20817702

RESUMEN

The objective of the present study was to elaborate a survival model that integrates anatomic factors, according to the 2010 seventh edition of the tumour, node and metastasis (TNM) staging system, with clinical and molecular factors. Pathologic TNM descriptors (group A), clinical variables (group B), laboratory parameters (group C) and molecular markers (tissue microarrays; group D) were collected from 512 early-stage nonsmall cell lung cancer (NSCLC) patients with complete resection. A multivariate analysis stepped supervised learning classification algorithm was used. The prognostic performance by groups was: areas under the receiver operating characteristic curve (C-index): 0.67 (group A), 0.65 (Group B), 0.57 (group C) and 0.65 (group D). Considering all variables together selected for each of the four groups (integrated group) the C-index was 0.74 (95% CI 0.70-0.79), with statistically significant differences compared with each isolated group (from p = 0.006 to p < 0.001). Variables with the greatest prognostic discrimination were the presence of another ipsilobar nodule and tumour size > 3 cm, followed by other anatomical and clinical factors, and molecular expressions of phosphorylated mammalian target of rapamycin (phospho-mTOR), Ki67cell proliferation index and phosphorylated acetyl-coenzyme A carboxylase. This study on early-stage NSCLC shows the benefit from integrating pathological TNM, clinical and molecular factors into a composite prognostic model. The model of the integrated group classified patients with significantly higher accuracy compared to the TNM 2010 staging.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/genética , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Estadificación de Neoplasias/métodos , Anciano , Algoritmos , Área Bajo la Curva , Carcinoma de Pulmón de Células no Pequeñas/terapia , Estudios de Cohortes , Humanos , Antígeno Ki-67/biosíntesis , Neoplasias Pulmonares/terapia , Oncología Médica/métodos , Persona de Mediana Edad , Metástasis de la Neoplasia , Probabilidad , Pronóstico , Factores de Tiempo
7.
Rev Clin Esp ; 210(9): 457-61, 2010 Oct.
Artículo en Español | MEDLINE | ID: mdl-20846647

RESUMEN

A 57-year old woman with arterial hypertension under treatment. She has smoked since she was 18 years old with an accumulated index of 70 years/pack. She was studied in our Respiratory Department due to constitutional syndrome, the X-ray showing an image of focal pulmonary lesion in the right upper lobe of more than 3cm of peripheral location. The computed tomography (CT) scan confirmed the existence of a 3.3cm mass in the upper right lobe and detected paratracheal and subcarinal mediastinal abnormal lymph nodes. A subsequent Positron Emission Tomography (PET) confirmed pathological uptake of the mass and both lymph node locations. Which additional studies do you consider to be indicated for a correct diagnosis and mediastinal staging? Do bronchoscopy techniques alone establish the final diagnosis and staging of this patient?


Asunto(s)
Broncoscopía , Carcinoma Broncogénico/diagnóstico , Neoplasias Pulmonares/diagnóstico , Femenino , Humanos , Persona de Mediana Edad , Factores de Tiempo
8.
Cell Death Differ ; 17(10): 1636-44, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20395962

RESUMEN

We compare here the neurodegenerative processes observed in the hippocampus of bitransgenic mice with chronically altered levels of cAMP-response element-binding protein (CREB) function. The combination of genome-wide transcriptional profiling of degenerating hippocampal tissue with microscopy analyses reveals that the sustained inhibition of CREB function in A-CREB mice is associated with dark neuron degeneration, whereas its strong chronic activation in VP16-CREB mice primarily causes excitotoxic cell death and inflammation. Furthermore, the meta-analysis with gene expression profiles available in public databases identifies relevant common markers to other neurodegenerative processes and highlights the importance of the immune response in neurodegeneration. Overall, these analyses define the ultrastructural and transcriptional signatures associated with these two forms of hippocampal neurodegeneration, confirm the importance of fine-tuned regulation of CREB-dependent gene expression for CA1 neuron survival and function, and provide novel insight into the function of CREB in the etiology of neurodegenerative processes.


Asunto(s)
Proteína de Unión a Elemento de Respuesta al AMP Cíclico/fisiología , Hipocampo/ultraestructura , Degeneración Nerviosa/inmunología , Degeneración Nerviosa/patología , Animales , Apoptosis , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/genética , Perfilación de la Expresión Génica , Proteína Vmw65 de Virus del Herpes Simple/genética , Proteína Vmw65 de Virus del Herpes Simple/metabolismo , Hipocampo/metabolismo , Inflamación/etiología , Ratones , Ratones Transgénicos , Degeneración Nerviosa/genética , Neuronas/citología , Neuronas/metabolismo , Neuronas/ultraestructura , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo
9.
Anal Bioanal Chem ; 392(6): 1241-8, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18797851

RESUMEN

Superheated liquids of different polarity have been used for sequential extraction of fatty acids and phenols from alperujo. Multivariate methodology has been used to optimise the static-dynamic extraction. Forty-two minutes are required to complete extraction (20 mg/kg of fatty acids and up to 2,200 mg/kg of hydroxytyrosol in the raw material used). The efficacy of the extraction has been demonstrated and compared with that of conventional methods (Folch and stirring-based methods for fatty acids and phenols, respectively), which needed 4.5 and 24 h for the extraction of fatty acids and phenols, respectively. The non-polar and polar extracts were injected into GC-MS and HPLC-MS-MS equipment, respectively, for individual separation-quantification of the target compounds. The simplicity of the experimental setup and the low costs of the raw material make the proposed method advisable when extraction of both fractions is required.


Asunto(s)
Biotecnología/métodos , Ácidos Grasos/aislamiento & purificación , Calor , Fenoles/aislamiento & purificación , Aceites de Plantas/química , Solventes/química , Acetonitrilos/química , Antioxidantes/aislamiento & purificación , Biotecnología/economía , Biotecnología/instrumentación , Cloroformo/química , Cromatografía Líquida de Alta Presión/métodos , Formiatos/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Aceite de Oliva , Alcohol Feniletílico/análogos & derivados , Alcohol Feniletílico/aislamiento & purificación , Factores de Tiempo , Agua/química
10.
Neuroscience ; 154(1): 315-28, 2008 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-18434029

RESUMEN

Spherical cells in the anteroventral division of the cochlear nucleus, which relay excitatory inputs from the auditory nerve, also receive both GABAergic and glycinergic inhibitory synapses. Inhibition mediated by GABA and glycine fulfils essential roles in the processing abilities of these and other auditory neurons. However, the developmental program leading to a mature complement of GABAergic and glycinergic synapses and microcircuits is largely unknown. Because of their relatively simple geometry, spherical cells provide an excellent model for unraveling basic developmental patterns of inhibitory synaptogenesis. Using a combination of high resolution immunocytochemical methods, we report that, in the rat, synapses containing GABA or glycine are deployed on spherical cell bodies over a time period extending well beyond hearing onset. Such postnatal developmental recruitment of inhibitory endings is progressive, although there are two distinct leaps in their numbers. The first occurs by the end of the first postnatal week, prior to hearing onset, and the second, during the third postnatal week, after hearing onset. This pattern suggests that adjustments in inhibition could be driven by acoustic experience. While GABAergic and glycinergic endings are maturing and growing in number and size, their neurotransmitter content also appears to be developmentally regulated. Quantitative ultrastructural immunocytochemistry with colloidal gold suggests that GABA and glycine accumulation in synaptic endings follows a staggered pattern, with labeling stabilizing at adult levels by postnatal day 21. This may account for adjustments in synaptic efficacy and strength.


Asunto(s)
Núcleo Coclear/citología , Inhibición Neural/fisiología , Neuronas/fisiología , Sinapsis/fisiología , Factores de Edad , Animales , Animales Recién Nacidos , Regulación del Desarrollo de la Expresión Génica/fisiología , Glicina/metabolismo , Masculino , Microscopía Inmunoelectrónica/métodos , Neuronas/metabolismo , Neuronas/ultraestructura , Ratas , Ratas Wistar , Sinapsis/metabolismo , Sinapsis/ultraestructura , Ácido gamma-Aminobutírico/metabolismo
11.
J Agric Food Chem ; 56(7): 2505-11, 2008 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-18324773

RESUMEN

A liquid-liquid extraction method to enrich edible oils--olive, sunflower, and soy oils--with phenols from olive leaf extracts is proposed. After microwave assistance to remove the phenols from three varieties of olive leaves, concentrations in the extracts between 12921 and 5173 mg/L of oleuropein, between 488 and 192 mg/L of apigenin-7-glucoside, between 444 and 219 mg/L of luteolin-7-glucoside, and between 501 and 213 mg/L of verbascoside were obtained, which clearly depended on the target variety. After optimization of the liquid-liquid extraction step, the concentrations in oils were 442, 162, and 164 mg/L of oleuropein, respectively, which were also enriched in apigenin-7-glucoside (between 8 and 15 mg/L, depending of the oil), lutelin-7-glucoside (between 11 and 12 mg/L), and verbascoside (between 11 and 13 mg/L). The oil-extract distribution factor of these compounds was also calculated for all olive leaf varieties and edible oils using different extracts concentrations and also different oil-extract volume ratios. Thus, a door is open to enrichment of any oil with olive phenols at preset concentrations using extracts preconcentrated as required and taking into account the distribution factor of the target compounds between the oil and the extracts.


Asunto(s)
Grasas Insaturadas en la Dieta/análisis , Alimentos Fortificados/análisis , Olea/química , Fenoles/aislamiento & purificación , Extractos Vegetales/química , Hojas de la Planta/química , Manipulación de Alimentos/métodos , Fenoles/análisis , Aceites de Plantas/química , Aceite de Soja/química , Aceite de Girasol
12.
Rev Clin Esp ; 208(11): 551-6, 2008 Dec.
Artículo en Español | MEDLINE | ID: mdl-19121265

RESUMEN

INTRODUCTION: We define focal pulmonary lesion (FPL) as an intra-parenchymatous pulmonary lesion that is well circumscribed and completely surrounded by healthy lung. It is considered that the profitability of the fine needle aspiration puncture (FNAP) in FPL < or = 2 cm is better than that of the fibrobronchoscopy (FBC). OBJECTIVE: To analyze the diagnostic profitability of the FNAP in the malignant FPL and study if it varies according to site, size and histology. MATERIAL AND METHODS: We analyzed all the FBCs of our Unit between 01/2000 and 12/2001 in patients with solitary FLP < or = 6 cm with a definitive diagnosis of malignancy. The diagnostic profitability by size, site and histology was analyzed with Pearson's chi(2) statistics. RESULTS: 124 patients. Mean FBC per patient was 1.3. A total of 101 cases (82%) were diagnosed with FBC, 15 by thoracotomy and 8 by FNAP. Global diagnostic profitability of the FBC was 0.82 and the transbronchial biopsy 0.76. There are no diagnostic profitability differences by size (< or = 2 cm vs > 2 cm) (0.81 vs 0.82 p = 0.96), site (peripheral vs central) (0.79 vs 0.85 p = 0.41) and histology (epidermoid vs adenocarcinoma) (0.89 vs 0.75 p = 0.21). CONCLUSION: Profitability of the FBC in malignant FPL in our hospital is elevated without differences by size, site or histology. In our site, the initial diagnostic approach of the FLP is done with FBC.


Asunto(s)
Broncoscopía/métodos , Carcinoma Broncogénico/diagnóstico , Neoplasias Pulmonares/diagnóstico , Anciano , Biopsia , Carcinoma Broncogénico/patología , Diagnóstico Diferencial , Femenino , Humanos , Neoplasias Pulmonares/patología , Masculino , Sensibilidad y Especificidad
13.
Anal Chim Acta ; 602(1): 82-8, 2007 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-17936110

RESUMEN

Microwave-assisted extraction (MAE) has been used for the simultaneous isolation of polar and nonpolar compounds from alperujo using methanol-water and n-hexane as extractant system. Multivariate methodology has been used to establish the optimum extraction conditions. The target fractions (phenol compounds and fatty acids) were quantitatively extracted within 14 min. Following leaching and separation of the two phases by centrifugation, the polar and nonpolar fractions were analysed by HPLC-MS-MS and GC-MS, respectively. The proposed method was compared with the reference method for the isolation of each fraction (Folch method and stirring-based method for fatty acids and biophenols extraction, respectively) in terms of efficiency and extract composition. The paramount importance of both fractions, the simplicity of the MAE approach and the low costs of the raw material make advisable the implementation of the proposed method at an industrial scale.

14.
J Agric Food Chem ; 55(11): 4584-8, 2007 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-17488032

RESUMEN

The extraction of biophenols (BPs) from small branches (fibrous softwood) of olive tree accelerated by microwave assistance is proposed for the first time. Under optimal working conditions, no further extraction of the target analytes was achieved after 10 min, so complete removal of them within this interval was assumed (amounts ca. to 19000, 1000, 2000, 900, and 700 mg/kg of oleuropein, verbascoside, tyrosol, alpha-taxifolin, and hydroxytyrosol, respectively; the three last BPs are absent in branch-free olive leaves). The extracts required no cleanup or concentration prior to injection into a chromatograph-photodiode array detector assembly for individual separation-quantification. Extraction from this raw material was also implemented in continuous and discontinuous-continuous extractors using ultrasound assistance and superheated liquids, respectively, as auxiliary energies, and the results were compared with those obtained by microwave-assisted extraction. The simultaneous extraction of small branches and leaves from olive tree provided extracts with a higher variety of BPs, but either extracts richer in oleuropein and verbascoside without tyrosol, alpha-taxifolin, and hydroxytyrosol or rich in these three BPs can be obtained by separate extraction of leaves and branches, respectively.


Asunto(s)
Olea/química , Fenoles/química , Fenoles/aislamiento & purificación , Árboles/química , Cromatografía Líquida de Alta Presión , Microondas , Tallos de la Planta/química
15.
J Agric Food Chem ; 54(26): 9706-12, 2006 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-17177490

RESUMEN

The peak areas from a high-performance liquid chromatography-diode array (HPLC-DAD) analysis of biophenols extracted from olive leaves have been used as chemotaxonomic markers to construct chemometric models in order to discriminate and classify (1) 13 varieties of Olea europaea olive trees, namely, Alameño, Arbequina, Azulillo, Chorna, Hojiblanca, Lechín, Manzanillo, Negrillo, Nevadillo, Ocal, Pierra, Sevillano, and Tempranillo, from the same cultivation zone and (2) Arbequina samples from six different geoghaphical origins, namely, Córdoba, Mallorca (north and south), Ciudad Real, Lleida, and Navarra. Models based on principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used for discrimination between samples as a function of the tree varieties and cultivation zone, whereas K nearest neighbors (KNN) and soft independent modeling of class analogy (SIMCA) models were generated to classify the samples used to validate the models into one of the groups previously established by PCA and HCA. KNN classified correctly 93 and 92% of the samples into the variety and cultivation zone, respectively; meanwhile, the SIMCA models predicted 85 and 92%, respectively.


Asunto(s)
Olea/química , Olea/clasificación , Fenoles/análisis , Hojas de la Planta/química , Cromatografía Líquida de Alta Presión , Olea/crecimiento & desarrollo , Extractos Vegetales/química , España , Especificidad de la Especie
16.
J Chromatogr A ; 1136(2): 185-91, 2006 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-17045596

RESUMEN

Oleuropein and other healthy olive biophenols (OBPs) such as verbacoside, apigenin-7-glucoside and luteolin-7-glucoside have been extracted from olive leaves by using superheated liquids and a static-dynamic approach. Multivariate methodology has been used to carry out a detailed optimisation of the extraction. Under the optimal working conditions, complete removal without degradation of the target analytes was achieved in 13 min. The extract was injected into a chromatograph-photodiode array detector assembly for individual separation-quantification. The proposed approach - which provides more concentrated extracts than previous alternatives - is very useful to study matrix-extractant analytes partition. In addition, the efficacy of superheated liquids to extract OBPs, the simplicity of the experimental setup, its easy automation and low acquisition and maintenance costs make the industrial implementation of the proposed method advisable.


Asunto(s)
Olea/química , Fenoles/aislamiento & purificación , Hojas de la Planta/química , Piranos/aislamiento & purificación , Métodos Analíticos de la Preparación de la Muestra/métodos , Apigenina/aislamiento & purificación , Glucósidos/aislamiento & purificación , Calor , Concentración de Iones de Hidrógeno , Glucósidos Iridoides , Iridoides , Luteolina/aislamiento & purificación , Reproducibilidad de los Resultados
17.
Anal Bioanal Chem ; 385(4): 753-9, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16741775

RESUMEN

Microwave assistance is proposed for the first time in order to accelerate the extraction of biophenols from olive leaves. Under optimal working conditions, obtained using a multivariate methodology, complete extraction of the target analytes was achieved in 8 min. The extracts required no clean-up nor concentration prior to injection into a chromatograph-photodiode array detector assembly for individual separation-quantification. The optimal extractant (an 80:20 ethanol-water mixture) was also used in the development of a stirring-based extraction method which required around 24 h for complete extraction of the target compounds. These mixtures can be used as replacements for toxic extractants, with a view to exploiting olive leaves in order to obtain biophenols for human use.


Asunto(s)
Microondas , Olea/química , Fenoles/química , Fenoles/aislamiento & purificación , Piranos/química , Piranos/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas , Concentración de Iones de Hidrógeno , Glucósidos Iridoides , Iridoides , Cinética , Estructura Molecular , Extractos Vegetales/química , Hojas de la Planta/química
18.
Eur J Neurosci ; 23(6): 1479-90, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16553611

RESUMEN

The highest densities of the two metabotropic GABA subunits, GABAB1 and GABAB2, have been reported as occurring around the glutamatergic synapses between Purkinje cell spines and parallel fibre varicosities. In order to determine how this distribution is achieved during development, we investigated the expression pattern and the cellular and subcellular localization of the GABAB1 and GABAB2 subunits in the rat cerebellum during postnatal development. At the light microscopic level, immunoreactivity for the GABAB1 and GABAB2 subunits was very prominent in the developing molecular layer, especially in Purkinje cells. Using double immunofluorescence, we demonstrated that GABAB1 was transiently expressed in glial cells. At the electron microscopic level, immunoreactivity for GABAB receptors was always detected both pre- and postsynaptically. Presynaptically, GABAB1 and GABAB2 were localized in the extrasynaptic membrane of parallel fibres at all ages, and only rarely in GABAergic axons. Postsynaptically, GABAB receptors were localized to the extrasynaptic and perisynaptic plasma membrane of Purkinje cell dendrites and spines throughout development. Quantitative analysis and three-dimensional reconstructions further revealed a progressive developmental movement of the GABAB1 subunit on the surface of Purkinje cells from dendritic shafts to its final destination, the dendritic spines. Together, these results indicate that GABAB receptors undergo dynamic regulation during cerebellar development in association with the establishment and maturation of glutamatergic synapses to Purkinje cells.


Asunto(s)
Cerebelo/metabolismo , Receptores de GABA-B/fisiología , Sinapsis/fisiología , Animales , Animales Recién Nacidos , Cerebelo/citología , Cerebelo/crecimiento & desarrollo , Técnica del Anticuerpo Fluorescente , Técnicas para Inmunoenzimas , Inmunohistoquímica , Ratas , Ratas Wistar
19.
J Chromatogr A ; 1108(1): 76-82, 2006 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-16442552

RESUMEN

A continuous approach for the ultrasound-assisted extraction of olive biophenols (OBPs) from olive leaves is proposed. Multivariate methodology was used to carry out a detailed optimisation of extraction. Under the optimal working conditions, complete extraction of the target analytes (namely, oleuropein, verbacoside, apigenin-7-glucoside and luteolin-7-glucoside with LODs 11.04, 2.68, 1.49 and 3.91 mg/kg, respectively) was achieved in 25 min. The extract was injected into a chromatograph-photodiode array detector assembly (HPLC-DAD) for individual separation-quantification. No clean-up or preconcentration steps were required. Gas chromatography-mass spectrometry (without derivatization of the analytes) was used to identify OBPs at concentrations below the LODs obtained by HPLC-DAD. The efficacy of ethanol-water mixtures to extract OBPs from olive leaves has been demonstrated and compared with that of a conventional method which requires 24h for complete extraction; so these mixtures can substitute toxic extractants used to date.


Asunto(s)
Olea/química , Hojas de la Planta/química , Piranos/aislamiento & purificación , Ultrasonido , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Glucósidos Iridoides , Iridoides , Fenoles/aislamiento & purificación , Reproducibilidad de los Resultados
20.
Neuroscience ; 130(3): 567-80, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15590141

RESUMEN

Our understanding of the role played by neurotransmitter receptors in the developing brain has advanced in recent years. The major excitatory and inhibitory neurotransmitters in the brain, glutamate and GABA, activate both ionotropic (ligand-gated ion channels) and metabotropic (G protein-coupled) receptors, and are generally associated with neuronal communication in the mature brain. However, before the emergence of their role in neurotransmission in adulthood, they also act to influence earlier developmental events, some of which occur prior to synapse formation: such as proliferation, migration, differentiation or survival processes during neural development. To fulfill these actions in the constructing of the nervous system, different types of glutamate and GABA receptors need to be expressed both at the right time and at the right place. The identification by molecular cloning of 16 ionotropic glutamate receptor subunits, eight metabotropic glutamate receptor subtypes, 21 ionotropic and two metabotropic GABA receptor subunits, some of which exist in alternatively splice variants, has enriched our appreciation of how molecular diversity leads to functional diversity in the brain. It now appears that many different types of glutamate and GABA receptor subunits have prominent expression in the embryonic and/or postnatal brain, whereas others are mainly present in the adult brain. Although the significance of this differential expression of subunits is not fully understood, it appears that the change in subunit composition is essential for normal development in particular brain regions. This review focuses on emerging information relating to the expression and role of glutamatergic and GABAergic neurotransmitter receptors during prenatal and postnatal development.


Asunto(s)
Encéfalo/crecimiento & desarrollo , Encéfalo/fisiología , Ácido Glutámico/fisiología , Receptores de GABA/fisiología , Transducción de Señal/fisiología , Animales , Diferenciación Celular/fisiología , Movimiento Celular/fisiología , Proliferación Celular , Humanos , Neuronas/fisiología , Receptores de Neurotransmisores/fisiología , Sinapsis/fisiología
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