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1.
Physiol Mol Biol Plants ; 29(10): 1423-1435, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38076759

RESUMEN

Lycopene cyclases (LCYs) are a key branching point in regulating the carotenoid biosynthesis pathway in plants. Bixa orellana L. is characterized by the presence in its seed of bixin, an apocarotenoid of significant importance in the food, pharmaceutical, and cosmetic industries. Gene analysis provides the opportunity to investigate the LCY gene structure in plant species and its relationship with the synthesis of carotenoids. Coding sequences of the LCY genes were retrieved from a B. orellana genome DNA. Boß-LCY1 and Boß-LCY2 genes exhibit 100% of identity to their respective cDNA accessions, and exhibit a single coding region of 1512 bp (504 aa) and 1495 bp (498 aa), respectively. In contrast, Boε-LCY gene shows a coding region of 1581 bp (527 aa) with 10 introns of diverse lengths. Putative Transcription Factors (TFs) binding sites were upstream (3000 bp) identified for each LCY gene. TFs cover two groups, one with the categories of photosynthesis, reproduction, and oxidative processes that are frequent. The second one with the categories of defense, cell cycle, signaling, and carbohydrate metabolism, which are poorly represented. Besides, repetitive DNA elements showed motifs and proteins related to LTR from the Ty3/Gypsy family, were associated with the TFs regions. In general, TFs vary in the different BoLCY genes, being more abundant in the Boε-LCY gene. LCY expression analyzed from a transcriptome database, and validated by RT-qPCR, shows an upregulation of the three LCYs, mainly oriented to the synthesis of essential carotenoids in photosynthetic tissues (leaves), as well as an upregulation of the Boß-LCY2 gene in the non-photosynthetic tissues (firsts seed development stages) related to the bixin accumulation. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-023-01384-8.

2.
Physiol Mol Biol Plants ; 28(4): 709-718, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35592485

RESUMEN

Fruit morphology and dehiscence-related genes were analyzed in dehiscent N4P and dehiscent P12 Bixa orellana accessions. Fruit architecture (exocarp and pericarp cells, trichomes, vascular bundles, vesicles, and bixin cells) documented by Scanning electron microscopy (SEM) morphology, blue toluidine stain, and phloroglucinol and hydrochloric acid (PHCL) stain was similar in both accessions. Although, the dehiscent zone (DZ) was higher in the indehiscent P12 B. orellana accession, lignification values, obtained by phloroglucinol and hydrochloric acid stain, within the DZ remain was similar in both variants being lower at 34 days after floral anthesis in the dehiscent N4P B. orellana accession. Dehiscence-related genes APETALA (AP2), SHATTERPROOF (SHP), and SPATULA (SPT) were identified on the reported B. orellana transcriptome (SRX1117606). Real-time quantitative polymerase chain reaction primers build by using these genes allow observing a differential expression during six fruit development stages. In both B. orellana accessions, the AP2 transcripts have a reduced expression, whereas the SHP transcripts were significantly higher during the first two days and ten days of development. SPT transcripts show an expression differential between both accessions being significantly higher in the dehiscent N4P, peaking with 9.66% at 42 days after floral anthesis (DAFA) of development. SPT transcription profile suggested that this gene has an important role during the fruit opening in the dehiscent N4P B. orellana accession. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-022-01180-w.

3.
Langmuir ; 36(1): 477-478, 2020 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-31887045

RESUMEN

We address the issues raised in the Tadmor article (Tadmor, T., et al. Comment on "Comparison of the Lateral Retention Forces on Sessile, Pendant, and Inverted Sessile Drops". Langmuir 2019, 10.1021/acs.langmuir.9b02660). In particular, we explain why we did not use Tadmor's theory to explain our results.

4.
Nanotechnology ; 27(42): 425501, 2016 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-27622391

RESUMEN

We present a glucose biosensor based on ZnO nanowire self-sustained films grown on compacted graphite flakes by the vapor transport method. Nanowire/graphite films were fragmented in water, filtered to form a colloidal suspension, subsequently functionalized with glucose oxidase and finally transferred to a metal electrode (Pt). The obtained devices were evaluated using scanning electron microscopy, energy-dispersive x-ray spectroscopy, cyclic voltammetry and chronoamperometry. The electrochemical responses of the devices were determined in buffer solutions with successive glucose aggregates using a tripolar electrode system. The nanostructured biosensors showed excellent analytical performance, with linear response to glucose concentrations, high sensitivity of up to ≈17 µA cm(-2) mM(-1) in the 0.03-1.52 mM glucose concentration range, relatively low Michaelis-Menten constant, excellent reproducibility and a fast response. The detection limits are more than an order of magnitude lower than those achievable in commercial biosensors for glucose control, which is promising for the development of glucose monitoring methods that do not require blood extraction from potentially diabetic patients. The strong detection enhancements provided by the functionalized nanostructures are much larger than the electrode surface-area increase and are discussed in terms of the physical and chemical mechanisms involved in the detection and transduction processes.

5.
Assist Technol ; 25(2): 80-7, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23923690

RESUMEN

We report the results of a study on the learnability ofhaptic icons used in a system for incoming-call identification in mobile phones. The aim was to explore the feasibility of using haptic icons to create new assistive technologies for people with visual impairments. We compared the performance and satisfaction of users with different visual capacities (visually impaired vs. sighted) and using different learning processes (unimodal vs. multimodal). A better recognition rate and user experience were observed for the visually impaired than for sighted users and for multimodal rather than unimodal learning processes.


Asunto(s)
Recursos Audiovisuales , Teléfono Celular , Aprendizaje , Interfaz Usuario-Computador , Trastornos de la Visión/psicología , Adulto , Humanos , Satisfacción del Paciente , Estimulación Física , Trastornos de la Visión/terapia , Adulto Joven
6.
Neurologia (Engl Ed) ; 2022 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-35963536

RESUMEN

INTRODUCTION: Genomic studies have identified numerous genetic variants associated with susceptibility to multiple sclerosis (MS); however, each one explains only a small percentage of the risk of developing the disease. These variants are located in genes involved in specific pathways, which supports the hypothesis that the risk of developing MS may be linked to alterations in these pathways, rather than in specific genes. We analyzed the role of the TNFRSF1A gene, which encodes one of the TNF-α receptors involved in a signaling pathway previously linked to autoimmune disease. METHODS: We included 138 individuals from 23 families including at least 2 members with MS, and analyzed the presence of exonic variants of TNFRSF1A through whole-exome sequencing. We also conducted a functional study to analyze the pathogenic mechanism of variant rs4149584 (-g.6442643C > G, NM_001065.4:c.362 G > A, R92Q) by plasmid transfection into human oligodendroglioma (HOG) cells, which behave like oligodendrocyte lineage cells; protein labeling was used to locate the protein within cells. We also analyzed the ability of transfected HOG cells to proliferate and differentiate into oligodendrocytes. RESULTS: Variant rs4149584 was found in 2 patients with MS (3.85%), one patient with another autoimmune disease (7.6%), and in 5 unaffected individuals (7.46%). The 2 patients with MS and variant rs4149584 were homozygous carriers and belonged to the same family, whereas the remaining individuals presented the variant in heterozygosis. The study of HOG cells transfected with the mutation showed that the protein does not reach the cell membrane, but rather accumulates in the cytoplasm, particularly in the endoplasmic reticulum and near the nucleus; this suggests that, in the cells presenting the mutation, TNFRSF1 does not act as a transmembrane protein, which may alter its signaling pathway. The study of cell proliferation and differentiation found that transfected cells continue to be able to differentiate into oligodendrocytes and are probably still capable of producing myelin, although they present a lower rate of proliferation than wild-type cells. CONCLUSIONS: Variant rs4149584 is associated with risk of developing MS. We analyzed its functional role in oligodendrocyte lineage cells and found an association with MS in homozygous carriers. However, the associated molecular alterations do not influence the differentiation into oligodendrocytes; we were therefore unable to confirm whether this variant alone is pathogenic in MS, at least in heterozygosis.

7.
J Exp Bot ; 62(15): 5385-95, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21813796

RESUMEN

Carotenoid cleavage dioxygenases (CCDs) are a class of enzymes involved in the biosynthesis of a broad diversity of secondary metabolites known as apocarotenoids. In plants, CCDs are part of a genetic family with members which cleave specific double bonds of carotenoid molecules. CCDs are involved in the production of diverse and important metabolites such as vitamin A and abscisic acid (ABA). Bixa orellana L. is the main source of the natural pigment annatto or bixin, an apocarotenoid accumulated in large quantities in its seeds. Bixin biosynthesis has been studied and the involvement of a CCD has been confirmed in vitro. However, the CCD genes involved in the biosynthesis of the wide variety of apocarotenoids found in this plant have not been well documented. In this study, a new CCD1 gene member (BoCCD1) was identified and its expression was charaterized in different plant tissues of B. orellana plantlets and adult plants. The BoCCD1 sequence showed high homology with plant CCD1s involved mainly in the cleavage of carotenoids in several sites to generate multiple apocarotenoid products. Here, the expression profiles of the BoCCD1 gene were analysed and discussed in relation to total carotenoids and other important apocarotenoids such as bixin.


Asunto(s)
Bixaceae/enzimología , Dioxigenasas/metabolismo , Proteínas de Plantas/metabolismo , Bixaceae/genética , Bixaceae/metabolismo , Carotenoides/metabolismo , Dioxigenasas/genética , Proteínas de Plantas/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
8.
J Cell Biol ; 58(1): 79-95, 1973 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-4125375

RESUMEN

A functionally coupled organotypic complex of cultured dorsal root ganglia, spinal cord peripheral nerve, and muscle has been employed in an experimental approach to the investigation of the neurotoxic effects of thallium. Selected cultures, grown for up to 12 wk in vitro, were exposed to thallous salts for periods ranging up to 4 days. Cytopathic effects were first detected after 2 h of exposure with the appearance of considerably enlarged mitochondria in axons of peripheral nerve fibers. With time, the matrix space of these mitochondria became progressively swollen, transforming the organelle into an axonal vacuole bounded by the original outer mitochondrial membrane. Coalescence of adjacent axonal vacuoles produced massive internal axon compartments, the membranes of which were shown by electron microprobe mass spectrometry to have an affinity for thallium. Other axoplasmic components were displaced within a distended but intact axolemma. The resultant fiber swelling caused myelin retraction from nodes of Ranvier but no degeneration. Impulses could still propagate along the nerve fibers throughout the time course of the experiment. Comparable, but less severe changes were seen in dorsal root ganglion neurons and in central nerve fibers. Other cell types showed no mitochondrial change. It is uncertain how these findings relate to the neurotoxic effects of thallium in vivo, but a sensitivity of the nerve cell and especially its axon to thallous salts is indicated.


Asunto(s)
Mitocondrias/efectos de los fármacos , Neuronas/efectos de los fármacos , Talio/farmacología , Animales , Embrión de Mamíferos , Ganglios/citología , Ganglios/efectos de los fármacos , Histocitoquímica , Espectrometría de Masas , Ratones , Microscopía Electrónica , Dilatación Mitocondrial , Músculos/citología , Músculos/efectos de los fármacos , Neuronas/citología , Técnicas de Cultivo de Órganos , Médula Espinal/citología , Médula Espinal/efectos de los fármacos , Coloración y Etiquetado , Factores de Tiempo
9.
Mol Biotechnol ; 42(1): 84-90, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19107604

RESUMEN

A reliable protocol is described for isolation of large full-length cDNA from Bixa orellana mature tissues containing large quantities of pigments, phenols, and polysaccharides. This protocol involves the optimization of a commercial RNA extraction protocol in combination with a long distance reverse transcript PCR protocol. The principal advantages of this protocol are its high RNA yield and quality. The resulting RNA is suitable for RNA expression evaluation and production of large, full-length cDNA. This is the first time RNA has been isolated from all mature tissues in the tropical perennial plant B. orellana and has been proved viable for downstream applications, especially important for molecular biology studies on this economically important pigment-producing plant.


Asunto(s)
Bixaceae/genética , Técnicas de Amplificación de Ácido Nucleico/métodos , Componentes Aéreos de las Plantas/química , ARN de Planta/aislamiento & purificación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Bixaceae/química , Carotenoides/análisis , Carotenoides/química , ADN Complementario/síntesis química , Electroforesis en Gel de Agar , Flavonoides/análisis , Flavonoides/química , Fenoles/análisis , Fenoles/química , Componentes Aéreos de las Plantas/genética , Polifenoles , Polisacáridos/análisis , Polisacáridos/química , ARN de Planta/química
10.
Rev Esp Enferm Dig ; 101(2): 107-12, 112-6, 2009 Feb.
Artículo en Inglés, Español | MEDLINE | ID: mdl-19335046

RESUMEN

AIM: Colonoscopy has become accepted as the most effective method for colon exploration. Some application problems have been detected in the setting of normal clinical care due to its wide range of uses in recent years, and therefore there is a need to measure colonoscopy quality. For that purpose valid quality indicators are necessary to be defined. The application process of some quality indicators is presented in this study. The proposed indicators in this study are: quality of bowel preparation, cecal intubation rate, withdrawal time, adenoma detection rate, and adenoma removal rate. MATERIAL AND METHOD: This is a prospective 12-month study where colonoscopies performed in the VI health area of Murcia Region were evaluated. From February 2006 to February 2007 a total of 609 subjects were eligible for colonoscopy after a positive fecal blood test in the setting of a colorectal cancer screening program. A sample of thirty patients (n: 30) was considered representative to assess the reliability of quality indicators and for a preliminary analysis of results. RESULTS: Indicators results are: quality of bowel preparation (87%), kappa 0.74 (95% CI: 0.48-0.99); cecal intubation rate (90%) 0.74 (95% CI: 0.49-0.99); adenoma detection and removal rate (96%), kappa: 0.78 (95% CI: 0.53-0.99); withdrawal time: 13.36 min (95% CI: 10.48-16.11). Kappa: 0.78 (95% CI: 0.49-0.99). CONCLUSIONS: Quality indicators definition and application in colonoscopy performance is possible. More studies are necessary to define the role of these indicators in the setting of clinical practice.


Asunto(s)
Colonoscopía/normas , Catárticos , Ciego , Pólipos del Colon/patología , Pólipos del Colon/cirugía , Colonoscopía/métodos , Neoplasias Colorrectales/diagnóstico , Sedación Consciente , Humanos , Hiperplasia , Tamizaje Masivo , Sangre Oculta , Cuidados Preoperatorios , Estudios Prospectivos , Garantía de la Calidad de Atención de Salud , Indicadores de Calidad de la Atención de Salud , España , Factores de Tiempo
11.
Cardiovasc Eng Technol ; 10(4): 618-627, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31598894

RESUMEN

PURPOSE: Prompt detection of congestion is an essential target in order to prevent heart failure (HF) related hospitalization, being ambulatory monitoring a promising strategy to do so. A successful non-invasive ambulatory monitoring system requires automatic devices for physiological data recording; these data must give information about HF deterioration early enough to predict HF-related adverse events. This work aims to evaluate seven vascular parameters for the ambulatory monitoring of congestive heart failure patients. METHODS: Seven vascular parameters are proposed as indicators of HF deterioration. These parameters are obtained using venous occlusion plethysmography; a technique that uses hardware able of being miniaturized and easily integrated into wearables for ambulatory monitoring. The ability of the proposed vascular parameters to detect congestion is evaluated in eight healthy volunteers and ten congestive heart failure patients with different congestion levels-mild, moderate and severe. RESULTS: Most parameters distinguish between healthy volunteers and heart failure patients, and some of them present significant differences between volunteers and low levels of congestion-mild or moderate. CONCLUSION: Home monitoring of some of the proposed parameters could detect HF deterioration on its onset and alert to health personnel.


Asunto(s)
Insuficiencia Cardíaca/diagnóstico , Hemodinámica , Monitoreo Ambulatorio/métodos , Pletismografía , Telemetría , Adulto , Anciano , Estudios de Casos y Controles , Diseño de Equipo , Femenino , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/terapia , Humanos , Masculino , Persona de Mediana Edad , Miniaturización , Modelos Cardiovasculares , Monitoreo Ambulatorio/instrumentación , Pletismografía/instrumentación , Valor Predictivo de las Pruebas , Pronóstico , Prueba de Estudio Conceptual , Índice de Severidad de la Enfermedad , Telemetría/instrumentación , Función Ventricular Izquierda , Dispositivos Electrónicos Vestibles , Adulto Joven
12.
Astron Astrophys ; 5972017 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-28190887

RESUMEN

Yellow hypergiants are rare and represent a fast evolutionary stage of massive evolved stars. That evolutionary phase is characterised by a very intense mass loss, the understanding of which is still very limited. Here we report ALMA Compact Array observations of a 50″-mosaic toward the Fried Egg nebula, around one of the few Galactic yellow hypergiants IRAS 17163-3907. The emission from the 12CO J=2-1 line, H30α recombination line, and continuum is imaged at a resolution of ~8″, revealing the morphology of the molecular environment around the star. The continuum emission is unresolved and peaks at the position of the star. The radio recombination line H30α shows unresolved emission at the star, with an approximately gaussian spectrum centered on a velocity of 21±3 km s-1 with a width of 57±6 km s-1. In contrast, the CO 2-1 emission is complex and decomposes into several components beyond the contamination from interstellar gas in the line of sight. The CO spectrum toward the star is a broad plateau, centered at the systemic velocity of +18 km s-1 and with an expansion velocity of 100±10 km s-1. Assuming isotropic and constant mass-loss, we estimate a mass-loss rate of 8±1.5 ×10-5 M⊙ yr-1. At a radius of 25″ from the star, we detect CO emission associated with the dust ring previously imaged by Herschel. The kinematics of this ring, however, is not consistent with an expanding shell, but show a velocity gradient of vsys ±20 km s-1. In addition, we find a puzzling bright feature radially connecting the star to the CO ring, at a velocity of +40 km s-1 relative to the star. This spur feature may trace a unidirectional ejection event from the star. Our ACA observations reveal the complex morphology around IRAS 17163 and illustrate the breakthroughs that ALMA will bring to the field of massive stellar evolution.

13.
An Med Interna ; 23(8): 385-6, 2006 Aug.
Artículo en Español | MEDLINE | ID: mdl-17067246

RESUMEN

The small bowel leiomyosarcoma is a infrequent tumour in the clinical practice. We report the case of a 50 year old male admitted to the hospital on two occasions for gastrointestinal bleeding. On the second occasion a push enteroscopy located in jejunum a tumour. The pathologic diagnosis was a low grade jejunal leiomyosarcoma. The patient required a surgical intervention with resection of the affected portion of the jejunum.


Asunto(s)
Hemorragia Gastrointestinal/etiología , Neoplasias del Yeyuno/complicaciones , Leiomiosarcoma/complicaciones , Humanos , Masculino , Persona de Mediana Edad
14.
J Mol Biol ; 235(4): 1357-63, 1994 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-8308900

RESUMEN

Using a clone characterized in the course of a random sequencing programme of Arabidopsis thaliana, two cDNAs encoding plant type cytosolic NADPH-dependent thioredoxin reductase (NTR) have been isolated. Their sequence homology with Escherichia coli NRT (the only thioredoxin reductase of known primary structure) is about 45%. In addition, analysis of the sequence of the encoded polypeptide (333 amino acids) reveals that several motifs are conserved in the FAD, central and NADPH binding domains, suggesting a similar folding of the protein. Definitive proof that the clone ATTHIREDB indeed encodes NTR was obtained by expressing the recombinant protein in E. coli cells. It was observed that plant type NTR was strongly overproduced (about 10 mg homogeneous protein could be purified per liter of culture). The recombinant enzyme is homodimeric, each subunit containing an FAD prosthetic group. Recombinant plant type NTR is as effective as E. coli NTR in the DTNB (5,5'-dithiobis nitrobenzoic acid) reduction reaction, but its affinity for thioredoxin substrates was strikingly different. These results are discussed in relation to the primary structures of NADPH thioredoxin reductases.


Asunto(s)
Arabidopsis/enzimología , Reductasa de Tiorredoxina-Disulfuro/genética , Secuencia de Aminoácidos , Clonación Molecular , Electroforesis en Gel de Poliacrilamida , Escherichia coli , Datos de Secuencia Molecular , NADP/metabolismo , Filogenia , Proteínas Recombinantes/biosíntesis , Homología de Secuencia de Aminoácido , Reductasa de Tiorredoxina-Disulfuro/biosíntesis , Reductasa de Tiorredoxina-Disulfuro/clasificación
16.
Gastroenterol Hepatol ; 28(8): 447-9, 2005 Oct.
Artículo en Español | MEDLINE | ID: mdl-16185579

RESUMEN

Hepatitis C virus (HCV) infection is a global problem in our health systems. The prevalence of infected patients in general population is about 2%. In the subgroup of pregnant woman the percentage of infected patients ranges from 1-3%. Several studies have described the relationship between pregnancy and chronic HCV infection, and in most cases serum transaminases levels return to normal values while HCV-RNA levels increase during the second and third trimester. The influence of maternal hormones after delivery in the natural history of HCV infection has not been sufficiently studied and consequently remains controversial. This case report shows the peculiar clinical course of a patient with chronic HCV infection in the puerperium.


Asunto(s)
Hepatitis C Crónica/complicaciones , Fallo Hepático/etiología , Trastornos Puerperales/etiología , Enfermedad Aguda , Adulto , Progresión de la Enfermedad , Femenino , Hormonas Esteroides Gonadales/fisiología , Humanos , Cirrosis Hepática/etiología , Fallo Hepático/cirugía , Trasplante de Hígado , Embarazo
17.
An Med Interna ; 22(9): 413-8, 2005 Sep.
Artículo en Español | MEDLINE | ID: mdl-16386072

RESUMEN

INTRODUCTION: The information is an important part of the attendance process though in occasions it can be inadequate or deficient. AIM: We detect an opportunity of improvement in the inadequate information of the patients who carry out an endoscopia. The aim is to evaluate and to improve the quality of the information. METHOD: We realize the first evaluation with 100 patients proceeding from consultations, detecting ignorance of the technology. Actions of improvement are applied, for 4 months, to realize the second evaluation, with the same number of patients and to evaluate improvement with regard to the situation of item. RESULTS: A deficit of information has been detected in the moment to indicate the endoscopia (little information contributed by the doctor prescriptor and in an important number of cases informed assent was not contributed) and after realizing the test, not contributing recommendations. We prioritize our action to this level with measures of improvement and after a new evaluation, a significant improvement decides in these situations. CONCLUSIONS: The studies of qualit level allow us to detect deficit situations and to improve situations in the services of health.


Asunto(s)
Endoscopía , Educación del Paciente como Asunto , Encuestas y Cuestionarios , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad
18.
J Neuropathol Exp Neurol ; 42(3): 243-55, 1983 May.
Artículo en Inglés | MEDLINE | ID: mdl-6188808

RESUMEN

Adult Hartley guinea pigs were inoculated with an increased dose of whole central nervous system tissue in complete Freund's adjuvant in order to determine the effects of high dose of neuroantigens on the clinical and pathological course of experimental allergic encephalomyelitis (EAE). An increased survival rate during the first attack and a change in the course of the disease from an acute fatal one to chronic progressive EAE were observed. The main clinicopathological features of the disease included a delayed onset of mild neurological signs and the presence of large demyelinated plaques in the brain and spinal cord. The relationship of the chronic progressive course of the disease and the induction of high-zone tolerance is discussed.


Asunto(s)
Encéfalo/patología , Encefalomielitis Autoinmune Experimental/patología , Proteína Básica de Mielina/inmunología , Médula Espinal/patología , Animales , Encéfalo/inmunología , Encéfalo/ultraestructura , Modelos Animales de Enfermedad , Encefalomielitis Autoinmune Experimental/inmunología , Femenino , Cobayas , Tolerancia Inmunológica , Masculino , Proteína Básica de Mielina/administración & dosificación , Médula Espinal/inmunología
19.
FEBS Lett ; 402(2-3): 259-64, 1997 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-9037207

RESUMEN

In toad olfactory neurons, a putrid odorant mixture inducing inhibitory responses increases Ca2+-activated K+ conductance, developing a hyperpolarizing receptor potential. Removal of extracellular Ca2+ or exposure to nifedipine reversibly reduced the inhibitory response, suggesting that odorants induce a Ca2+ influx. We show evidence for an odorant-induced Ca2+ current. Using confocal microscopy, it is shown that odorants induce a nifedipine-sensitive elevation of Ca2+ in the apical end of the cell. These results suggest an inhibitory mechanism in which an apical Ca2+ influx causes an increase in internal Ca2+, opening Ca2+-activated K2+ channels that lead to membrane hyperpolarization.


Asunto(s)
Canales de Calcio/fisiología , Calcio/metabolismo , Calcio/farmacología , Odorantes , Neuronas Receptoras Olfatorias/fisiología , Animales , Anuros , Dendritas/efectos de los fármacos , Dendritas/fisiología , Técnicas In Vitro , Nifedipino/farmacología , Mucosa Olfatoria/inervación , Neuronas Receptoras Olfatorias/efectos de los fármacos , Técnicas de Placa-Clamp
20.
FEBS Lett ; 168(1): 139-42, 1984 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-6368263

RESUMEN

The presence of isolate-specific Trypanosoma cruzi minicircles has been shown in the kinetoplast DNA of this parasite. This led to the rapid identification of isolates and clones of trypanosomes by means of 'dot-spot' hybridizations with molecularly cloned minicircle probes. Unexpectedly, whole kDNAs were also suitable as probes for this purpose, provided that filters were washed under stringent conditions. This was attributed to the presence of the above-mentioned isolate-specific minicircle sequences. The fact that parasites could be directly spotted onto nitrocellulose filters simplified the rapid routine screening of a large number of samples.


Asunto(s)
Clonación Molecular , ADN/genética , Trypanosoma cruzi/genética , Animales , ADN/aislamiento & purificación , Hibridación de Ácido Nucleico , Trypanosoma cruzi/aislamiento & purificación
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