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Photolytic Degradation of Benorylate Effects of the Photoproducts on Cultured Hepatocytes

  • Castell, J.V
  • Gómez-Lechon, M.J.
  • Mirabet, V.
  • Miranda Alonso, Miguel Ángel|||0000-0002-7717-8750
  • Morera Bertomeu, Isabel María|||0000-0003-2120-2042
[EN] The photodegradation of benorylate [4¿-(acetamido)phenyl-2-acetoxybenzoate], a drug frequently used in rheumatoid arthritis therapy, has been examined under different sets of experimental conditions. Several photoproducts have been isolated and identified on the basis of their IR, NMR, and MS spectra. The most significant photochemical process is the photo-Fries rearrangement of benorylate, leading to 5-acetamido-2¿-acetoxy-2-hydroxybenzophenone (1). This compound undergoes a rapid transacylation to the isomeric 5¿-acetamido-2¿-acetoxy-2-hydroxybenzophenone (2). A primary culture of rat hepatocytes has been used to evaluate the possible toxicity of these two benzophenones, keeping in mind the following criteria: leakage of cytosolic enzymes, attachment index to culture plates, gluconeogenesis from lactate and fructose, glycogen balance, and albumin synthesis. At the concentrations assayed, neither of the two major photoproducts of benorylate (benzophenones 1 and 2) had significant toxic effects on liver cells in culture., Financial support Comisión Asesora de Investigación Científica y Técnica (grant no.1325) is gratefully acknowledged.
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Toxic Effects of the Photoproducts of Chlorpromazine on Cultured Hepatocytes

  • Castell, J. V.
  • Gómez-Lechón, M.
  • Miranda Alonso, Miguel Ángel|||0000-0002-7717-8750
  • Morera Bertomeu, Isabel María|||0000-0003-2120-2042
[EN] The photodegradation of chlorpromazine, a drug frequently used in psychotherapy, was examined under different sets of experimental conditions. A primary culture of rat hepatocytes was used to evaluate the possible hepatotoxicity of the chlorpromazine photoproducts, keeping in mind the following criteria: leakage of cytosolic enzymes; attachment index to culture plates, and albumin synthesis. Cells exposed to concentrations greater than 10¿4 M of the photomixtures showed extensive leakage of GOT and GPT into the culture medium and, at the same time, the cell attachment was seriously impaired. A concentration of 10¿7 M of the photoproducts proved capable of inhibiting the synthesis of albumin (20%). Photoproducts obtained after aerobic irradiations were as toxic for hepatocytes as those found in anaerobic conditions. The implications of our results in connection with the relevance of oxygen¿dependent photoreactions of chlorpromazine to its phototoxicity, and the possible appearance of hepatic alterations in patients treated with the drug after exposure to the sunlight, are discussed., Thie study was supported by the Fondo de Investigaciones Sanitarias de la Seguridad Social (Grant 83/0982) and by the Comisión Asesora de Investigación Cientiífica y Técnica (Grant 1325)
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Influence of food and temperature on development and oviposition of Euseius stipulatus and Typhlodromus phialatus (Acari: Phytoseiidae)

  • Ferragut Pérez, Francisco José
  • García Mari, Ferran|||0000-0001-5798-1805
  • Costa Comelles, Jose
  • Laborda Cenjor, Rafael
[EN] The influence of feeding and temperature on life table parameters ofEuseius stipulatus (Athias-Henriot) andTyphlodromus phialatus Athias-Henriot was determined in laboratory tests. Both phytoseiids developed and reproduced readily when fed onCarpobrotus edulis (L.) pollen andPanonychus citri (McGregor) Intrinsic rates of increase (rm) at 25°C forE. stipulatus andT. phialatus were 0.197 and 0.126, and, when fed onP. citri, 0.129 and 0.144, respectively.Tetranychus urticae Koch offered as prey allowed normal development and oviposition ofT. phialatus, but no eggs were laid byE. stipulatus when fed on this spider mite. Eggs and honeydew ofAleurothrixus floccosus Mask. furnished sufficient nutrition for development of immatures ofE. stipulatus. Larvae ofPlanoccocus citri Risso, and honeydew and eggs ofA. floccosus, allowed adult survival but no egg-laying of the predaceous mites.Lorryia formosa Cooreman was not a favoured prey species. Life tables were calculated forE. stipulatus fed on pollen andT. phialatus fed onP. citri at constant temperatures of 18, 25, and 32°C. Maximum development was reached at 32°C, withrm values of 0.225 forE. stipulatus and 0.179 forT. phialatus. In general, both phytoseiids showed medium to high total number of eggs per female and long oviposition periods when compared with other phytoseiid species. When mating took place at 32°C,E. stipulatus females were not able to lay eggs, thus suggesting an interference of high temperatures with fertilization in this species. No hatching was observed in eggs of either species when kept at relative humidities of 50% or lower. The possible significance of these responses is discussed in relation to population trends observed in the field.
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Alcohol de Biomasa II. Hidrólisis de las pentosanas de tallos y zuros de maíz, tallos de sorgo dulce, paja de arroz y sarmientos

  • García-Breijo, Francisco-José
  • Primo Yufera, Eduardo
[ES] Se determinan los productos de 13 hidrolisis acida suave en distintas condiciones, de los siguientes materales: tallos y zuros de maiz Funk's, var. G-5050 y de maiz sacarino, var. E41, ta1I0s de sorgo dulce, var. Wray, paja de arroz, var. Bollia y sarmientos de vid, var. Bobal. En todas las experiencias se han mantenido constantes el tamano de particula (25 mallas), la relacion solido/liquido (1 / 10) y la temperatura ' (ebullicion a retlujo). micntras que la concentracion de acido sulfurico se ha variado del 2 al 9 % y el tiempo de I a 4 horas. Los resultados obtenidos permiten seleccionar las condiciones mas adecuadas para conseguir una elevada hidrolisis de pen tosanas con minima degradacion a furfural. Entre los materiales estudiados destacan los zuroS de maiz de am bas variedades, con rendimientos en la hidrolisis cercanos al 80 % de sus pentosanas (aprox. 200 kg/ ton en los de maiz sacarino y 230 kg!ton en los de maiz Funk's) y con degradaciones a furfural no muy elevadas (inferiores al 25 % de las pentosanas hidrolizadas).
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Per a una edició crítica de les obres completes de Jacint Verdaguer

  • Farrés, Pere
  • Molas, Joaquim
  • Pinyol i Torrents, Ramon
  • Torrents, Ricard
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Investigación: La inteligencia y las cualidades psicomotrices

  • Lavega i Burgués, Pere
  • Ruiz Sánchez, Pedro
Son varios los autores que han estudiado la posible relación entre aspectos de tipo cognoscitivo y motrices en deficientes mentales. Mediante el presente estudio pretendemos contribuir a esclarecer el citado tema. Para ello contamos con una muestra de treinta sujetos de 11 y 12 años disminuidos psíquicos. Tras pasar diferentes baterías de tests psicomotrices y de condición física, se han calculado y analizado las correlaciones entre el grado de desarrollo psicomotriz y el C.I., llegando a las siguientes conclusiones: El C.I. es un factor condicionante pero no determinante al plantear programas de educación física en deficientes mentales. Las experiencias motrices de los sujetos se deben de tener en cuenta, puesto que de ellas depende en gran medida la heterogeneidad en el desarrollo motriz de esta población. Es importante utilizar un «coeficiente psicomotriz» para establecer grupos homogéneos tanto en las clases de E.F. como en los deportes competitivos. Un programa adecuado y sistematizado de E.F. puede incrementar los niveles psicomotrices y de ejecución de los individuos. Como conclusión final deberemos tener presente que la E.F. es tanto o más necesaria en los deficientes psíquicos que en la población normal y que es preciso hacer una valoración global del individuo, evaluando su nivel de desarrollo psicomotriz a la hora de plantear programas de E.F.
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