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1.
AJNR Am J Neuroradiol ; 34(11): 2113-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23744697

RESUMEN

BACKGROUND AND PURPOSE: Progressive changes in the substantia nigra pars compacta and locus ceruleus of patients with Parkinson disease and Alzheimer disease visualized by neuromelanin MRI and cardiac postganglionic sympathetic nerve function on (123)I-metaiodobenzylguanidine scintigraphy have not been fully evaluated. We compared the diagnostic value of these modalities among patients with early Parkinson disease, late Parkinson disease, and Alzheimer disease. MATERIALS AND METHODS: We compared contrast ratios of signal intensity in medial and lateral regions of the substantia nigra pars compacta and locus ceruleus with those of the tegmentum of the midbrain and the pons, respectively, by use of neuromelanin MRI in patients with early Parkinson disease (n = 13), late Parkinson disease (n = 31), Alzheimer disease (n = 6), and age-matched healthy control subjects (n = 20). We calculated heart-to-mediastinum ratios on (123)I-metaiodobenzylguanidine scintigrams after setting regions of interest on the left cardiac ventricle and upper mediastinum. RESULTS: The signal intensity of the lateral substantia nigra pars compacta on neuromelanin MRI was significantly reduced in early and late Parkinson disease, and that of the medial substantia nigra pars compacta was gradually and stage-dependently reduced in Parkinson disease. The signal intensity of the locus ceruleus was obviously reduced in late Parkinson disease. Signal reduction was not significant in the substantia nigra pars compacta and locus ceruleus of patients with Alzheimer disease. The heart-to-mediastinum ratio on (123)I-metaiodobenzylguanidine scintigrams was stage-dependently reduced in Parkinson disease and normal in Alzheimer disease. The signal intensity ratios in substantia nigra pars compacta and locus ceruleus on neuromelanin MRI positively correlated with the heart-to-mediastinum ratio on (123)I-metaiodobenzylguanidine scintigrams. CONCLUSIONS: Both neuromelanin MRI and (123)I-metaiodobenzylguanidine scintigraphy can help to evaluate disease progression in Parkinson disease and are useful for differentiating Parkinson disease from Alzheimer disease.


Asunto(s)
3-Yodobencilguanidina/farmacocinética , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/metabolismo , Encéfalo/metabolismo , Melaninas/metabolismo , Enfermedad de Parkinson/diagnóstico , Enfermedad de Parkinson/metabolismo , Anciano , Anciano de 80 o más Años , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Imagen Molecular/métodos , Tomografía de Emisión de Positrones/métodos , Radiofármacos/farmacocinética , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Distribución Tisular
3.
Bioinformatics ; 19(13): 1727-9, 2003 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-15593410

RESUMEN

A new version of the E-Cell simulation system,which runs on Windows as well as Linux, has been released as free software under the terms of the GNU General Public License.


Asunto(s)
Células/metabolismo , Modelos Biológicos , Programas Informáticos , Algoritmos , Presentación de Datos , Lenguajes de Programación , Diseño de Software , Interfaz Usuario-Computador
4.
Bioinformatics ; 15(1): 72-84, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10068694

RESUMEN

MOTIVATION: Genome sequencing projects and further systematic functional analyses of complete gene sets are producing an unprecedented mass of molecular information for a wide range of model organisms. This provides us with a detailed account of the cell with which we may begin to build models for simulating intracellular molecular processes to predict the dynamic behavior of living cells. Previous work in biochemical and genetic simulation has isolated well-characterized pathways for detailed analysis, but methods for building integrative models of the cell that incorporate gene regulation, metabolism and signaling have not been established. We, therefore, were motivated to develop a software environment for building such integrative models based on gene sets, and running simulations to conduct experiments in silico. RESULTS: E-CELL, a modeling and simulation environment for biochemical and genetic processes, has been developed. The E-CELL system allows a user to define functions of proteins, protein-protein interactions, protein-DNA interactions, regulation of gene expression and other features of cellular metabolism, as a set of reaction rules. E-CELL simulates cell behavior by numerically integrating the differential equations described implicitly in these reaction rules. The user can observe, through a computer display, dynamic changes in concentrations of proteins, protein complexes and other chemical compounds in the cell. Using this software, we constructed a model of a hypothetical cell with only 127 genes sufficient for transcription, translation, energy production and phospholipid synthesis. Most of the genes are taken from Mycoplasma genitalium, the organism having the smallest known chromosome, whose complete 580 kb genome sequence was determined at TIGR in 1995. We discuss future applications of the E-CELL system with special respect to genome engineering. AVAILABILITY: The E-CELL software is available upon request. SUPPLEMENTARY INFORMATION: The complete list of rules of the developed cell model with kinetic parameters can be obtained via our web site at: http://e-cell.org/.


Asunto(s)
Fenómenos Fisiológicos Celulares , Células/metabolismo , Simulación por Computador , Modelos Biológicos , Programas Informáticos , Adenosina Trifosfato/metabolismo , Inteligencia Artificial , Gráficos por Computador , Presentación de Datos , Enzimas/metabolismo , Expresión Génica , Ingeniería Genética , Unión Proteica , Transcripción Genética , Interfaz Usuario-Computador
5.
Artículo en Inglés | MEDLINE | ID: mdl-11072314

RESUMEN

We present E-CELL, a generic computer software environment for modeling a cell and conducting experiments in silico. The E-CELL system allows a user to define functions of proteins, protein-protein interactions, protein-DNA interactions, regulation of gene expression and other features of cellular metabolism, in terms of a set of reaction rules. The system then executes those reactions iteratively, and the user can observe, through a computer display, dynamic changes in concentrations of proteins, protein complexes and other chemical compounds in the cell. Using this software, we constructed a model of a hypothetical cell with only 127 genes sufficient for transcription, translation, energy production and phospholipid synthesis. Most of the genes are taken from Mycoplasma genitalium, the organism having the smallest known chromosome, whose complete 580kb genome sequence was determined at TIGR in 1995. We discuss future applications of the E-CELL system with special respect to genome engineering.

6.
Poult Sci ; 74(4): 648-55, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7792236

RESUMEN

To develop a method to detect hidden inflammation using serum protein in chickens, changes in serum proteins with acute inflammation were analyzed using a turpentine-induced inflammation model. Inflammation in the pectoral muscle of a 14-wk-old White Leghorn became apparent 3 h after the injection of turpentine and became more severe thereafter. Coincident with the development of inflammation, changes in serum proteins were analyzed by electrophoresis on polyacrylamide gradient gels. The electrophoretic patterns were divided into 21 segments. Two of these segments increased remarkably. These were located near the center of the electrophoretic pattern and were identified as transferrin due to iron staining, correlation of movement against a commercial transferrin sample in SDS-PAGE, and immunoblotting. These results suggest that transferrin may serve as a marker for inflammation in chicken.


Asunto(s)
Reacción de Fase Aguda/veterinaria , Proteínas Sanguíneas/análisis , Pollos/sangre , Reacción de Fase Aguda/sangre , Reacción de Fase Aguda/inducido químicamente , Reacción de Fase Aguda/patología , Animales , Electroforesis en Gel de Poliacrilamida , Femenino , Inyecciones Intramusculares , Hierro/sangre , Transferrina/análisis , Trementina
7.
J Vet Med Sci ; 55(1): 27-31, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8461423

RESUMEN

Polyacrylamide gel electrophoretic analysis of canine serum protein has revealed that the administration of anthelmintics elicits an increase in a certain serum protein. This protein, named PT60, was partially purified by ammonium sulfate fractionation and preparative electrophoresis. The purified PT60 gave a single band with the molecular size of 53 kDa in sodium dodecyl sulfate-polyacrylamide gel electrophoresis under non-reducing conditions. After reduction with 2-mercaptoethanol, two bands appeared at 35 kDa and 17 kDa, indicating that PT60 consists of two subunits which are linked with each other by disulfide bonds. PT60 had the capacity to bind to hemoglobin. In an immunodiffusion test, an antiserum against PT60 cross-reacted with canine haptoglobin (Hp). N-terminal amino acid sequences of two PT60 subunits were identical to those of alpha and beta subunits of canine Hp, respectively. Thus, PT60 was identified as Hp.


Asunto(s)
Antihelmínticos/farmacología , Perros/sangre , Haptoglobinas/aislamiento & purificación , Secuencia de Aminoácidos , Animales , Dirofilariasis/tratamiento farmacológico , Enfermedades de los Perros/tratamiento farmacológico , Electroforesis en Gel de Poliacrilamida/veterinaria , Femenino , Haptoglobinas/efectos de los fármacos , Masculino , Datos de Secuencia Molecular
8.
Nihon Hotetsu Shika Gakkai Zasshi ; 34(3): 592-8, 1990 Jun.
Artículo en Japonés | MEDLINE | ID: mdl-2135320

RESUMEN

To get a more natural and harmonious color of porcelain-fused-to-metal restorations, an objective and precise systematic method from shade selection to color evaluation is needed. Thus, the absorption and scattering coefficients were determined to develop a CCM system for porcelain-fused-to-metal restorations. The Kubelka-Munk Theory was applied on the dental porcelain, opaque, dentin, and enamel. From these data, we predicted the color of the porcelain mixtures from the both coefficients. From the results of comparing the spectral curves and analyzing the color differences between measured values and predicted values of porcelain mixtures, the following was analysed; 1. In opaque, spectral curves of the predicted and measured values were exactly alike and the mean dE between two values was 0.39. 2. In dentin, the spectral curved of the predicted and measured values were exactly alike, and the mean dE was 1.13. The measured values indicated a slight increase in the level of chroma and lightness. 3. In enamel, the spectral curves were exactly alike and the mean dE was 1.16. The measured values indicated a slight decrease in the level of lightness. Therefore, it was possible to predict the color of opaque, dentin and enamel porcelain mixtures, by applying the Kubelka-Munk Theory.


Asunto(s)
Color/normas , Porcelana Dental , Estética Dental , Adhesivos , Bisfenol A Glicidil Metacrilato , Colorimetría , Esmalte Dental , Dentina , Aleaciones de Cerámica y Metal
11.
Jpn J Pharmacol ; 28(3): 359-66, 1978 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-702940

RESUMEN

In the presence of tripropylsulfonium bromide (TPS) (1 X 10(-4) g/ml), a new compound, the phasic contraction of the isolated guinea pig ileum to 5-hydroxytryptamine (5-HT) (5 X 10(-7) g/ml) was consistently enhanced ("TPS effect"). TPS alone increased moderatley the spontaneous movement of the ileum. When the contraction height was calculated as the percentage of that to 5-HT alone, such was observed in the "TPS effect" to be 167.1 +/- 3.6% (mean +/- S.E., n = 80). TPS did not enhance the contraction due to acetylcholine or histamine. The "TPS effect" remained unaffected in the presence of dibenzyline (1 X 10(-7) g/ml), was abolished by morphine(1 X 10(-6) g/ml), tetrodotoxin (2 X 10(-8) g/ml) adenosine (3 X 10(-6) g/ml) and atropine (1 X 10(-7) g/ml) and was not observed under anoxic conditions. Eserine (1 X 10(-8) g/ml) strengthened the "TPS effect" markedly. It is concluded that this effect may be the result of the potentiating effect of TPS on the action of 5-HT through the M receptors, possibly by the facilitation of the acetylcholine-liberation from the nervous tissue.


Asunto(s)
Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Compuestos Onio/farmacología , Serotonina/farmacología , Compuestos de Sulfonio/farmacología , Acetilcolina/metabolismo , Acetilcolina/farmacología , Animales , Atropina/farmacología , Sinergismo Farmacológico , Femenino , Cobayas , Histamina/farmacología , Íleon , Técnicas In Vitro , Masculino , Morfina/farmacología , Terminaciones Nerviosas/metabolismo , Fisostigmina/farmacología , Compuestos de Sulfonio/antagonistas & inhibidores
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