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Morgado González Antonio - One of the best experts on this subject based on the ideXlab platform.
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Eficiencia de las rizobacterias promotoras del crecimiento vegetal (RPCV) en plántulas de caña de azúcar (Saccharum spp.).
Colegio de Postgraduados (COLPOS), 2013Co-Authors: Morgado González AntonioAbstract:Las Rizobacterias Promotoras de Crecimiento Vegetal (RPCV) son una alternativa en la nutrición de plantas cultivadas, ya que estimulan su crecimiento y rendimiento, mejorando la absorción de nutrimentos, el aumento en su movilización, la producción de antibióticos y de reguladores de crecimiento. La caña de azúcar (Saccharum spp.) es un cultivo muy demandante de nutrimentos y de alto rendimiento en México, el uso de las RPCV es fundamental para mejorar su rentabilidad. En esta investigación, se evaluó la efectividad en producción de índoles totales por el método Salkowski, solubilización de fosfatos con medio Pikovskaya de 24 cepas bacterianas de siete especies, y su impacto en el desarrollo de vitroplantas de caña de azúcar de la variedad Mex 69-290 al ser inoculadas. Las cepas fueron previamente identificadas, en el Laboratorio de Interacción Molecular Planta-Microorganismo del Colegio de Postgraduados, las especies utilizadas fueron Aeromonas salmonicida, Burkholderia cepacia, Ochrobactrum anthropi, Pseudomonas sp., Shewanella putrefaciens, Sphingomonas paucimobilis, y se propagaron en caldo nutritivo. Esta investigación se encuentra adscrita a la Línea Prioritaria de Investigación 5 (LPI) del Colegio de Postgraduados. La unidad experimental fue una maceta con una mezcla esterilizada con 50% de suelo agrícola y 50% de agrolita, con una plántula de caña de azúcar producida in vitro. Se inoculó 1.0 mL de cultivo bacteriano (1X107 UFC) por maceta. El experimento se desarrolló en invernadero por 90 días, en un diseño experimental completamente al azar, con 24 tratamientos, un testigo y cinco repeticiones. Se realizaron cinco muestreos destructivos quincenales para medir las variables respuesta: altura, diámetro de tallo, número de macollos, área foliar, biomasa seca de la parte aérea y de la raíz. La especie Ochrobactrum anthropi fue superior en producción de indoles con valores de 116.69 y 115.70 µg mL-1 así como Pseudomonas luteola con 117.35 µg mL-1. En relación a la solubilización de fosfatos, Stenotrophomonas maltophilia presentó los valores más altos: 222.43 y 216.38 µg mL-1. Del total de cepas inoculadas, 13 fueron superiores en diferentes variables respuesta. La altura se incrementó en 27.75% en promedio con respecto al testigo, el diámetro en 30.75%, el número de macollos en 38.5%, el área foliar en 49%, el peso de materia seca aérea y de raíz en 50.75 y 59.5% respectivamente. En cuanto al índice de área foliar (IAF), tasa de asimilación neta (TAN), tasa relativa y absoluta de crecimiento (TRC y TAC), P. luteola, P. fluorescens, Oanthropi y S. maltophilia fueron las cepas que mostraron mayores efectos positivos. Las cepas P. luteola (Tratamiento 1), O. anthropi (T5), Aeromonas salmonicida (T15), Burkholderia cepacia (T16), P. fluorescens (T22) y S. maltophilia (T24) fueron las más destacadas en diferentes variables respuesta y su constante persistencia en el tiempo, siendo potenciales para ser utilizadas como biofertilizantes en el cultivo de caña de azúcar de forma individual o en consorcios, aunque son necesarios estudios de antibiosis para conocer la compatibilidad entre los microorganismos evaluados. _______________ EFFICIENCY OF PLANT GROWTH PROMOTING RHIZOBACTERIA (PGPR) ON SUGAR CANE (Saccharum spp.) PLANTLESS. ABSTRACT: Plant Growth Promoting Rhizobacteria (PGPR) are used as an alternative for nutrition of cultivated plants, since such bacteria are able to estimulate plant growth and yield, through processes such as nitrient uptake improvement, mineral movilization increase, biosíntesis of antibiotics and growth regulators. Sugar cane (Saccharum spp.) is a crop plant which demands high amount of nutrients and shows high yields in Mexico, therefore, the use of PGPR is crucial for improving its profits. In this research we evaluated the efficiency of production of total indols for Salkowski, phospahte solubility for Picovskaya method, of 24 bacterial strains belonging to seven different species, and its impact on sugar cane plantlets variety Mex 69-290 when being inoculated with such bacteria. Bacterial strains were previously characterized in the Laboratory of Plant-Microorganis Molecular Interaction from Colegio de Postgraduados, belonging to the species Aeromonas salmonicida, Burkholderia cepacia, Ochrobactrum anthropi, Pseudomonas sp., Shewanella putrefaciens, Sphingomonas paucimobilis and Stenotrophomonas maltophilia. Bacterial strains were propagated in a proper breeding ground. The experimental unit was a pot containing a sterile mixture of 50% crop soil and 50% agrolite, with a sugar cane plantless propagated in vitro. Each plant in the pot was inoculated with 1.0 mL of bacterial culture (1X107 UFC). The study was carried out in greenhouse during 90 days, using a completely randomized experiment with 24 treatments, a control, and five replicates each. After inoculation, five destructive samplings were performed every 15 days in order to measure response variables plant height, shoot diameter, number of stumps, foliar area, and dry biomass of shoot and roots. The species Ochrobactrum anthropi produced the highest amount of indols with values of 116.69 y 115.70 µg mL-1, as well as Pseudomonas luteola with 117.35 µg mL-1. Concerning phosphate solubilization, Stenotrophomonas maltophilia showed the highest values: 222.43 y 216.38 µg mL-1. From the total of bacterial strain inoculated, 13 showed superior effects on plant growth variables measured. Plant height increased 27.75% on average in comparison to the control; shoot diameter in 30.75%, number of stumps in 38.5%, foliar area in 49%, dry biomass of shoot and root 50.75 and 59.5%, respectively. In relation to foliar area index (IAF), net assimilation rate (TAN), relative and absolute growth rate (TRC and TAC), P. luteola, P. fluorescens, O. anthropi y S. maltophilia were the strains showing the strongest effects. The species P. luteola (Treatment 1), O. anthropi (T5), Aeromonas salmonicida (T15), Burkholderia cepacia (T16), P. fluorescens (T22) and S. maltophilia (T24) were the most prominent in different response variables and their permanence during the time of the experiment, and therefore can be used as biofertilizers in the sugar cane crop individually or associated, though studies on antibiosis in order to know compatibility strategies must be carried out in deep
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Eficiencia de las rizobacterias promotoras del crecimiento vegetal (RPCV) en plántulas de caña de azúcar (Saccharum spp.).
Colegio de Postgraduados (COLPOS), 2013Co-Authors: Morgado González AntonioAbstract:Las Rizobacterias Promotoras de Crecimiento Vegetal (RPCV) son una alternativa en la nutrición de plantas cultivadas, ya que estimulan su crecimiento y rendimiento, mejorando la absorción de nutrimentos, el aumento en su movilización, la producción de antibióticos y de reguladores de crecimiento. La caña de azúcar (Saccharum spp.) es un cultivo muy demandante de nutrimentos y de alto rendimiento en México, el uso de las RPCV es fundamental para mejorar su rentabilidad. En esta investigación, se evaluó la efectividad en producción de índoles totales por el método Salkowski, solubilización de fosfatos con medio Pikovskaya de 24 cepas bacterianas de siete especies, y su impacto en el desarrollo de vitroplantas de caña de azúcar de la variedad Mex 69-290 al ser inoculadas. Las cepas fueron previamente identificadas, en el Laboratorio de Interacción Molecular Planta-Microorganismo del Colegio de Postgraduados, las especies utilizadas fueron Aeromonas salmonicida, Burkholderia cepacia, Ochrobactrum anthropi, Pseudomonas sp., Shewanella putrefaciens, Sphingomonas paucimobilis, y se propagaron en caldo nutritivo. Esta investigación se encuentra adscrita a la Línea Prioritaria de Investigación 5 (LPI) del Colegio de Postgraduados. La unidad experimental fue una maceta con una mezcla esterilizada con 50% de suelo agrícola y 50% de agrolita, con una plántula de caña de azúcar producida in vitro. Se inoculó 1.0 mL de cultivo bacteriano (1X107 UFC) por maceta. El experimento se desarrolló en invernadero por 90 días, en un diseño experimental completamente al azar, con 24 tratamientos, un testigo y cinco repeticiones. Se realizaron cinco muestreos destructivos quincenales para medir las variables respuesta: altura, diámetro de tallo, número de macollos, área foliar, biomasa seca de la parte aérea y de la raíz. La especie Ochrobactrum anthropi fue superior en producción de indoles con valores de 116.69 y 115.70 µg mL-1 así como Pseudomonas luteola con 117.35 µg mL-1. En relación a la solubilización de fosfatos, Stenotrophomonas maltophilia presentó los valores más altos: 222.43 y 216.38 µg mL-1. Del total de cepas inoculadas, 13 fueron superiores en diferentes variables respuesta. La altura se incrementó en 27.75% en promedio con respecto al testigo, el diámetro en 30.75%, el número de macollos en 38.5%, el área foliar en 49%, el peso de materia seca aérea y de raíz en 50.75 y 59.5% respectivamente. En cuanto al índice de área foliar (IAF), tasa de asimilación neta (TAN), tasa relativa y absoluta de crecimiento (TRC y TAC), P. luteola, P. fluorescens, Oanthropi y S. maltophilia fueron las cepas que mostraron mayores efectos positivos. Las cepas P. luteola (Tratamiento 1), O. anthropi (T5), Aeromonas salmonicida (T15), Burkholderia cepacia (T16), P. fluorescens (T22) y S. maltophilia (T24) fueron las más destacadas en diferentes variables respuesta y su constante persistencia en el tiempo, siendo potenciales para ser utilizadas como biofertilizantes en el cultivo de caña de azúcar de forma individual o en consorcios, aunque son necesarios estudios de antibiosis para conocer la compatibilidad entre los microorganismos evaluados. _______________ EFFICIENCY OF PLANT GROWTH PROMOTING RHIZOBACTERIA (PGPR) ON SUGAR CANE (Saccharum spp.) PLANTLESS. ABSTRACT: Plant Growth Promoting Rhizobacteria (PGPR) are used as an alternative for nutrition of cultivated plants, since such bacteria are able to estimulate plant growth and yield, through processes such as nitrient uptake improvement, mineral movilization increase, biosíntesis of antibiotics and growth regulators. Sugar cane (Saccharum spp.) is a crop plant which demands high amount of nutrients and shows high yields in Mexico, therefore, the use of PGPR is crucial for improving its profits. In this research we evaluated the efficiency of production of total indols for Salkowski, phospahte solubility for Picovskaya method, of 24 bacterial strains belonging to seven different species, and its impact on sugar cane plantlets variety Mex 69-290 when being inoculated with such bacteria. Bacterial strains were previously characterized in the Laboratory of Plant-Microorganis Molecular Interaction from Colegio de Postgraduados, belonging to the species Aeromonas salmonicida, Burkholderia cepacia, Ochrobactrum anthropi, Pseudomonas sp., Shewanella putrefaciens, Sphingomonas paucimobilis and Stenotrophomonas maltophilia. Bacterial strains were propagated in a proper breeding ground. The experimental unit was a pot containing a sterile mixture of 50% crop soil and 50% agrolite, with a sugar cane plantless propagated in vitro. Each plant in the pot was inoculated with 1.0 mL of bacterial culture (1X107 UFC). The study was carried out in greenhouse during 90 days, using a completely randomized experiment with 24 treatments, a control, and five replicates each. After inoculation, five destructive samplings were performed every 15 days in order to measure response variables plant height, shoot diameter, number of stumps, foliar area, and dry biomass of shoot and roots. The species Ochrobactrum anthropi produced the highest amount of indols with values of 116.69 y 115.70 µg mL-1, as well as Pseudomonas luteola with 117.35 µg mL-1. Concerning phosphate solubilization, Stenotrophomonas maltophilia showed the highest values: 222.43 y 216.38 µg mL-1. From the total of bacterial strain inoculated, 13 showed superior effects on plant growth variables measured. Plant height increased 27.75% on average in comparison to the control; shoot diameter in 30.75%, number of stumps in 38.5%, foliar area in 49%, dry biomass of shoot and root 50.75 and 59.5%, respectively. In relation to foliar area index (IAF), net assimilation rate (TAN), relative and absolute growth rate (TRC and TAC), P. luteola, P. fluorescens, O. anthropi y S. maltophilia were the strains showing the strongest effects. The species P. luteola (Treatment 1), O. anthropi (T5), Aeromonas salmonicida (T15), Burkholderia cepacia (T16), P. fluorescens (T22) and S. maltophilia (T24) were the most prominent in different response variables and their permanence during the time of the experiment, and therefore can be used as biofertilizers in the sugar cane crop individually or associated, though studies on antibiosis in order to know compatibility strategies must be carried out in deep.Tesis (Maestría en Ciencias, especialista en Fisiología Vegetal).- Colegio de Postgraduados, 2013.Consejo Nacional de Ciencia y Tecnología (CONACYT)
Daoud Ali - One of the best experts on this subject based on the ideXlab platform.
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detection of oxidative stress and dna damage in freshwater snail lymnea leuteola exposed to profenofos
Frontiers of Environmental Science & Engineering in China, 2018Co-Authors: Daoud Ali, Huma Ali, Saad Alkahtani, Abdullah A Alkahtane, Saud Alifiri, Shaik Althaf HuasainAbstract:Extensive production and use of organophosphate pesticide in agriculture, has risen concerned about its ecotoxicity and risk assessment of insecticides, which are more important. Therefore, the present investigation was aimed to study the induction of oxidative stress and DNA damage by organophosphate insecticide profenofos (PFF) in freshwater snail Lymnea luteola (L. luteola). The median lethal value (96 h LC50) of PFF was estimated as 1.26 mg/L for L. luteola in a semi-static system and on the basis of LC50 value three concentrations viz., 0.126 (1/10 of LC50, Sublethal I), 0.63 (1/2 of LC50, Sublethal II) and 0.84 mg/L (2/3 of LC50, Sublethal III) were determined. Snails were exposed to above-mentioned concentrations of PFF along with solvent control (acetone) and negative control for 96 h. The haemolymph was collected at 24 and 96 h of after treatment. In heamolymph of PFF exposed snail, lipid peroxide, glutathione reduced glutathione S transferase and superoxide dismutase activities at the tested concentrations significantly differ from those in the control. The genotoxicity induced in hemocytes of treated snails was measured by alkaline single cell gel electrophoresis assay. The data of this experiment demonstrated significantly enhancement of oxidative stress and DNA damage in the treated snails as compared to controls. Also, we observed statistically significant correlations of ROS with DNA damage (% tail DNA) (R2 = 0.9708) for 24 h and DNA damage (R2 = 0.9665) for 96 h.
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genotoxicity in the freshwater gastropod lymnaea luteola l assessment of cell type sensitivities to lead nitrate
Chemistry and Ecology, 2017Co-Authors: Daoud Ali, Huma Ali, Saud Alarifi, Ali Alamer, Pintu Kumar, Sudhir Kumar, Agha Parvez Masih, Saad Alkahtani, Abdullah A Alkahtane, Shaik Althaf HussainAbstract:ABSTRACTThe aquatic ecosystems are converting into the highly contaminated site due to environmental pollutants. The present study explores the oxidative stress and toxic potential of lead nitrate in freshwater snail Lymnaea luteola (L. luteola) L. The snails were exposed to an environmentally relevant concentration of lead nitrate for 24 and 96 h. Later exposure to lead nitrate (0, 10, 20 and 40 µg/mL) to the freshwater snail, the level of reactive oxygen species, malondialdehyde and nitric oxide (NO) were increased and glutathione, glutathione-S-transferase were decreased. Lead-nitrate-induced haemocyte cell death and it was observed by using Annexin-V FITC/PI through a flow cytometer. DNA damage in haemocyte cells was measured at above doses of lead-nitrate exposure for 24 and 96 h and it was compared to the untreated snail. Average tail DNA (%) and olive tail moment in single-cell gel test were increased dose and duration fashion and maximum DNA damage was measured at 96 h. These results indicate the ...
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susceptibility of the freshwater pulmonate snail lymnea luteola l to copper oxide nanoparticle
Toxicological & Environmental Chemistry, 2015Co-Authors: Daoud Ali, Huma AliAbstract:Copper oxide nanoparticles (CuONP) are among the most widely used engineered nanoparticles and thus likely to permate the environment predominantly in sediments. The present study was designed to examine the adverse effects of CuONP in freshwater snail Lymnea luteola L. (L. luteola) exposed for 5 days. Induction of oxidative stress in digestive gland was evidenced by a decrease in reduced glutathione (GSH) levels, and activities of glutathione peroxidase (GPx) and glutathione-S-transferase (GST) whereas lipid peroxidation levels were increased at CuONP 7 or 21 µg/L. Superoxide dismutase activity was numerically higher at lower concentration of CuONP at 1 day but significantly decreased at 5 days. Catalase activity was reduced at 2 days but elevated at lower concentration of CuONP at 5 days. DNA impairment was noted in L. luteola based upon comet assay findings and expressed in terms of % tail DNA and olive tail moment. Results indicate that interaction of CuONP with snail produces toxicity, which is media...
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impairment of dna in a freshwater gastropod lymnea luteola l after exposure to titanium dioxide nanoparticles
Archives of Environmental Contamination and Toxicology, 2015Co-Authors: Daoud Ali, Huma Ali, Saud Alarifi, Sudhir Kumar, M Serajuddin, Agha P Mashih, Mukhtar Ahmed, Mujeeb Khan, Syed Farooq Adil, Mohammed Rafi ShaikAbstract:The apoptotic and genotoxic potential of titanium dioxide nanoparticles (TiO2NPs) were evaluated in hemocyte cells of freshwater snail Lymnealuteola L. Before evaluation of the toxic potential, mean size of the TiO2NPs was determined using a transmission electron microscopy and dynamic light scattering. In this study, L. luteola were exposed to different concentrations of TiO2NPs (28, 56, and 84 μg/ml) over 96 h. Induction of oxidative stress in hemolymph was observed by a decrease in reduced glutathione and glutathione-S-transferase levels at different concentration of TiO2NPs and, in contrast, an increase in malondialdehyde and reactive oxygen species levels. Catalase activity was decreased at lower concentrations but increased at greater concentration of TiO2NPs. The extent of DNA fragmentation occurring in L. luteola due to ecotoxic impact TiO2NPs was further substantiated by alkaline single-cell gel electrophoresis assay and expressed in terms of % tail DNA and olive tail moment. The alkaline single-cell gel electrophoresis assay for L. luteola clearly shown relatively greater DNA damage at the highest concentration of TiO2NPs.The results indicate that the interaction of TiO2NPs with snail influences toxicity, which is mediated by oxidative stress according dose and in a time-dependent manner. The results of this study showed the importance of a multibiomarker approach for assessing the injurious effects of TiO2NPs to freshwater snail L. luteola, which may be vulnerable due to the continuous discharge of TiO2NPs into the aquatic ecosystems. The measurement of DNA integrity in L. luteola thus provides an early warning signal of contamination of the aquatic ecosystem by TiO2NPs.
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sensitivity of freshwater pulmonate snail lymnaea luteola l to silver nanoparticles
Chemosphere, 2014Co-Authors: Daoud Ali, Huma Ali, Saud Alarifi, Sudhir Kumar, Phool Gend Yadav, Abdul Halim HarrathAbstract:Abstract Toxicity of nanoparticles depends on many factors including size, shape, chemical composition, surface area and surface charge. Silver nanoparticles (AgNPs) are likely to enter the aquatic ecosystems because of their multiple applications and pose a health concern for humans and aquatic species. Therefore, we used a freshwater snail Lymnaea luteola L ( L . luteola ) to investigate the acute toxicity and genotoxicity of AgNPs in a static-renewal system for 96 h. AgNPs caused molluscicidal activity in L . luteola , with 96-h median lethal concentrations (LC 50 ) (48.10 μg L −1 ). We have observed that AgNPs (36 μg L −1 ) elicited a significant ( p L . luteola . However, a significant ( p L . luteola . The oxidative stress biomarkers and comet assay can successfully be used as sensitive tools of aquatic pollution biomonitoring.
Ashraf Ahmed Montasser - One of the best experts on this subject based on the ideXlab platform.
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gram negative bacteria from the camel tick hyalomma dromedarii ixodidae and the chicken tick argas persicus argasidae and their antibiotic sensitivities
Journal of the Egyptian Society of Parasitology, 2005Co-Authors: Ashraf Ahmed MontasserAbstract:: A total of nine species of gram-negative bacteria were isolated from organs and haemolymph of the hard tick Hyalomma (Hyalomma) dromedarii and the soft tick Argas (Persicargas) persicus. Four species namely Serratia liquefaciens, Stenotrophomonas maltophilia, Klebsiella ornithinolytica and Aeromonas hydrophila were isolated from H. dromedarii and five species namely Rahnella aquatilis, Pseudomonas fluorescens, Enterobacter cloacae, Chryseomonas luteola and Chryseobacterium meningosepticum were isolated from A. persicus. Isolated bacteria were identified using the analytical profile index 20E. Disk diffusion test was carried out on all isolated bacteria to determine antibiotic sensitivity of chloramphenicol, amoxillin/clavulanic acid, neomycin, streptomycin, triplesulphur tetracycline and nitrofurantion. The results were discussed.
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gram negative bacteria from the camel tick hyalomma dromedarii ixodidae and the chicken tick argas persicus argasidae and their antibiotic sensitivities
Journal of the Egyptian Society of Parasitology, 2005Co-Authors: Ashraf Ahmed MontasserAbstract:A total of nine species of gram-negative bacteria were isolated from organs and haemolymph of the hard tick Hyalomma (Hyalomma) dromedarii and the soft tick Argas (Persicargas) persicus. Four species namely Serratia liquefaciens, Stenotrophomonas maltophilia, Klebsiella ornithinolytica and Aeromonas hydrophila were isolated from H. dromedarii and five species namely Rahnella aquatilis, Pseudomonas fluorescens, Enterobacter cloacae, Chryseomonas luteola and Chryseobacterium meningosepticum were isolated from A. persicus. Isolated bacteria were identified using the analytical profile index 20E. Disk diffusion test was carried out on all isolated bacteria to determine antibiotic sensitivity of chloramphenicol, amoxillin/clavulanic acid, neomycin, streptomycin, triplesulphur tetracycline and nitrofurantion. The results were discussed.
Chamson, Astrid De Reig - One of the best experts on this subject based on the ideXlab platform.
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Desarrollo y control de un tumor experimental de ovario
Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires, 1999Co-Authors: Chamson, Astrid De ReigAbstract:El objetivo de esta tesis fue el estudio de un modelo animal de tumor ovárico con ciertas similitudes con patologías ováricas hormono-dependientes y endocrinamente funcionales. El Luteoma se desarrolla al autoinjertar un ovario en el bazo de una rata hembra adulta bilateralmente ovariectomizada, por la hipergonadotrofinemia resultante. En estudios de un año de duración determinamos que son tumores benignos y no modifican el estado general del animal. La mayoria de los animales portadores de tumor cursan con gonadotrofinas elevadas por un período de tiempo prolongado. Los Luteomas secretan inhibina determinando un patrón particular de secreción de FSH. In vitro estos tumores presentan la esteroidogénesis basal alterada. La administración crónica de buserelina (análogo de GnRH)tuvo un claro efecto antitumoral: redujo la aparición de tumores e inhibió su crecimiento. A través de receptores específicos de afinidad similar al ovario control, la buserelina ejerce un efecto directo sobre las células de Luteomas: inhibe la secreción de progesterona estimulada por LH. Las células tumorales son más sensibles a este efecto que las células lúteas control. Sin embargo, los receptores para GnRH en las células de los Luteomas se encuentran desacoplados de su via clasica de segundos mensajeros: fosfolipasa C. En nuestros trabajos caracterizamos los Luteomas en diversos aspectos que abarcan al animal entero hasta estudios subcelulares.The aim of the present thesis was the study of an animal model of ovarian tumor. The interest of this tumor lies in its similarities with ovarian pathologies which are hormone-dependent and endocrinologically active. This Luteoma develops when an ovary is grafted into the spleen of a bilaterally ovariectomized adult female rat, as a consequence of the resulting hipergonadotrophinemia. In a year-long study we determined that these tumors are benign and do not alter the general condition of the animals. The majority of the tumor-bearing animals display high gonadotrophin levels for long periods of time. Luteoma secrete inhibins, which determine the particular FSH secretion pattern. In vitro these tumors show basal steroidogenesis alterations. Chronic buserelin (a GnRH analog) administration had a clear antitumoral effect: it inhibited initial tumor development and induced a reduction in tumor volume. Buserelin, acting on specific receptors with affinity similar to that in control ovaries, has a direct effect on Luteoma cells: it inhibits LH-stimulated progesterone secretion. Tumoral cells are more sensitive to this effect than control luteal cells. However, GnRH receptors in Luteoma cells are uncoupled from their classic second messenger generating system: phospholipase C. In our work we have characterized these Luteoma in a variety of aspects including the whole animal and subcellular studies.Fil:Chamson, Astrid de Reig. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina
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Desarrollo y control de un tumor experimental de ovario
Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires, 2024Co-Authors: Chamson, Astrid De ReigAbstract:El objetivo de esta tesis fue el estudio de un modelo animal de tumor ovárico con ciertas similitudes con patologías ováricas hormono-dependientes y endocrinamente funcionales. El Luteoma se desarrolla al autoinjertar un ovario en el bazo de una rata hembra adulta bilateralmente ovariectomizada, por la hipergonadotrofinemia resultante. En estudios de un año de duración determinamos que son tumores benignos y no modifican el estado general del animal. La mayoria de los animales portadores de tumor cursan con gonadotrofinas elevadas por un período de tiempo prolongado. Los Luteomas secretan inhibina determinando un patrón particular de secreción de FSH. In vitro estos tumores presentan la esteroidogénesis basal alterada. La administración crónica de buserelina (análogo de GnRH)tuvo un claro efecto antitumoral: redujo la aparición de tumores e inhibió su crecimiento. A través de receptores específicos de afinidad similar al ovario control, la buserelina ejerce un efecto directo sobre las células de Luteomas: inhibe la secreción de progesterona estimulada por LH. Las células tumorales son más sensibles a este efecto que las células lúteas control. Sin embargo, los receptores para GnRH en las células de los Luteomas se encuentran desacoplados de su via clasica de segundos mensajeros: fosfolipasa C. En nuestros trabajos caracterizamos los Luteomas en diversos aspectos que abarcan al animal entero hasta estudios subcelulares
Sorianello, Eleonora Mariana - One of the best experts on this subject based on the ideXlab platform.
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Differential gonadotropin releasing hormone (GnRH) expression, autoregulation and effects in two models of rat luteinized ovarian cells
'Elsevier BV', 2005Co-Authors: Sorianello, Eleonora Mariana, Fernandez, Marina Olga, Catalano, Paolo Nicolás, Mongiat, Lucas Alberto, Somoza, Gustavo Manuel, Libertun Carlos, Lux, Victoria Adela R.Abstract:GnRH has been suggested to participate in corpus luteum function. Here we studied the expression of GnRH mRNA and peptide in two models of rat luteinized tissues: ovarian cells from PMSG–hCG treated prepubertal rats (SPO) and from intrasplenic ovarian tumors (Luteoma). A GnRH autoregulatory effect was evaluated as well as its action on cell proliferation and apoptosis. GnRH mRNA was present in SPO, isolated corpora lutea from SPO and Luteoma from 1 week to 7 months of development. In vitro cultures of Luteoma cells expressed 2-fold higher GnRH mRNA and 10-fold higher GnRH peptide than SPO cells. Buserelin (GnRH analog) increased GnRH mRNA and peptide expression in SPO but not in Luteoma cells. While basal proliferation was very low in Luteoma cells, SPO cells showed a significant increase in cell number by both the thymidine and the MTS methods after 72 h in culture. Buserelin induced a decrease in cell number in both cell types to a similar degree. Although basal apoptosis levels were higher in SPO than in Luteoma cells, Buserelin-induced apoptosis was only detected in Luteoma cells after 48 h treatment. These results show that the two types of rat, luteinized tissues, Luteoma and SPO, markedly differed in some intrinsic properties and in their local GnRH systems. Luteoma cells proliferate very weakly, express and secrete high amounts of GnRH, do not show an autoregulatory effect and respond to the decapeptide with apoptosis stimulation. In contrast SPO cells proliferate significantly, secrete low levels of GnRH but possess a positive, autoregulatory mechanism and respond to GnRH stimulation with impairment of proliferation.Fil: Sorianello, Eleonora Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Universidad de Buenos Aires. Facultad de Medicina; ArgentinaFil: Fernandez, Marina Olga. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Universidad de Buenos Aires. Facultad de Medicina; ArgentinaFil: Catalano, Paolo Nicolás. Universidad de Buenos Aires. Facultad de Medicina; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Mongiat, Lucas Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Somoza, Gustavo Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: Libertun, Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Universidad de Buenos Aires. Facultad de Medicina; ArgentinaFil: Lux, Victoria Adela R.. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentin
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Fisiopatología de un tumor ovárico experimental
Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires, 2002Co-Authors: Sorianello, Eleonora MarianaAbstract:El objetivo de esta tesis fue el estudio de distintos aspectos de la biología y fisiopatología de un tumor ovárico experimental altamente luteinizado (Luteoma). Se analizaron parámetros relacionados a la proliferación celular, apoptosis, capacidad de síntesis esteroidogénica y de secreción del tumor. Se halló que el Luteoma se desarrollaría preferentemente por hipertrofia y proliferación de células foliculares y una marcada ausencia de apoptosis. Además se detectó la síntesis de las distintas subunidades de inhibina a lo largo de 7 meses de desarrollo tumoral; se evidenciaron patrones fluctuantes a lo largo del tiempo para las subunidades β, que correlacionan estrechamente con los niveles séricos de FSH, demostrando así que tejido altamente luteinizado es capaz de producir inhibinas. Posteriormente, se estudió el camino de señalización de un análogo superactivo del GnRH, Buserelina, en células provenientes del Luteoma, evidenciando que el camino clásico de transducción de señales acoplado al receptor de GnRH se encontraba alterado y hallándose los caminos altemativos activados por el decapéptido. Por otro lado, se puso de manifiesto la expresión del mRNA y del péptido de GnRH en células del Luteoma, postulándose para el mismo un papel autocrino/paracrino en dicho tejido. Finalmente, evaluamos el efecto de drogas inmunosupresoras, Ciclosporina A y Dexametasona, sobre el desarrollo del tumor in vivo en comparación con animales con operación ficticia (Sham) a lo largo de 7 semanas. Los resultados indicaron que, a pesar de ser efectiva la inmunosupresión inducida por estas drogas sobre variables inmunológicas, las mismas no afectaron el desarrollo tumoral. A diferencia de los animales portadores del tumor, en animales Sham la Ciclosporina A indujo efectos sobre varios parámetros, sugiriendo la presencia de factor/es secretado/s por el tumor que impiden o compensan algunas de las acciones de la droga. Estos estudios aportaron nuevos conocimientos acerca de caracteristicas relacionadas al desarrollo y capacidad de síntesis y secreción del Luteoma, como así también de caminos de señalización del receptor de GnRH y comportamiento del tumor bajo tratamiento con drogas inmunosupresoras.The aim of this thesis was to study different aspects regarding the biology and physiopathology of a highly luteinized experimental ovarian tumor (Luteoma). Parameters related to cellular proliferation, apoptosis, steroidogenic capacity and tumor secretion were analyzed. These demonstrated that tumors develop mainly due to proliferation of follicular cells, while a marked absence of apoptosis was also observed. In addition, synthesis of inhibin subunits was detected along 7 months of tumor growth, showing fluctuating expression of B subunits along development, tightly correlating with serum FSH levels. It was thus demonstrated that highly luteinized tissue is able to produce inhibins. The signaling pathways of a superactive analog of GnRH, Buserelin, were studied in Luteoma cells, showing that the classical transduction system coupled to the GnRH receptor was markedly altered and describing the alternate pathways activated by the decapeptide in Luteoma cells. Moreover, the expression of the GnRH mRNA and peptide was evidenced in Luteoma cells, suggesting a possible role as an autocrine/paracrine modulator. Furthermore, the effects of immunosuppressive drugs such as Cyclosporine A and Dexamethasone were evaluated on in vivo tumor growth in comparison to Sham-operated animals along 7 weeks of treatment. Results showed that even though the drug-induced immunosuppression was evidenced on immunological variables, tumor growth was not altered. Marking a difference with tumor-bearing rats, in Sham animals Cyclosporin A affected various parameters, suggesting tumor secreted factor/s which would inhibit or compensate some of the drug’s actions. These studies have contributed new understanding concerning tumor characteristics related to tumor growth, synthesis and secretion capacity as well as different signaling pathways activated by GnRH and tumor behavior under immunosuppression.Fil:Sorianello, Eleonora Mariana. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina
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Fisiopatología de un tumor ovárico experimental
Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires, 2024Co-Authors: Sorianello, Eleonora MarianaAbstract:El objetivo de esta tesis fue el estudio de distintos aspectos de la biología y fisiopatología de un tumor ovárico experimental altamente luteinizado (Luteoma). Se analizaron parámetros relacionados a la proliferación celular, apoptosis, capacidad de síntesis esteroidogénica y de secreción del tumor. Se halló que el Luteoma se desarrollaría preferentemente por hipertrofia y proliferación de células foliculares y una marcada ausencia de apoptosis. Además se detectó la síntesis de las distintas subunidades de inhibina a lo largo de 7 meses de desarrollo tumoral; se evidenciaron patrones fluctuantes a lo largo del tiempo para las subunidades β, que correlacionan estrechamente con los niveles séricos de FSH, demostrando así que tejido altamente luteinizado es capaz de producir inhibinas. Posteriormente, se estudió el camino de señalización de un análogo superactivo del GnRH, Buserelina, en células provenientes del Luteoma, evidenciando que el camino clásico de transducción de señales acoplado al receptor de GnRH se encontraba alterado y hallándose los caminos altemativos activados por el decapéptido. Por otro lado, se puso de manifiesto la expresión del mRNA y del péptido de GnRH en células del Luteoma, postulándose para el mismo un papel autocrino/paracrino en dicho tejido. Finalmente, evaluamos el efecto de drogas inmunosupresoras, Ciclosporina A y Dexametasona, sobre el desarrollo del tumor in vivo en comparación con animales con operación ficticia (Sham) a lo largo de 7 semanas. Los resultados indicaron que, a pesar de ser efectiva la inmunosupresión inducida por estas drogas sobre variables inmunológicas, las mismas no afectaron el desarrollo tumoral. A diferencia de los animales portadores del tumor, en animales Sham la Ciclosporina A indujo efectos sobre varios parámetros, sugiriendo la presencia de factor/es secretado/s por el tumor que impiden o compensan algunas de las acciones de la droga. Estos estudios aportaron nuevos conocimientos acerca de caracteristicas relacionadas al desarrollo y capacidad de síntesis y secreción del Luteoma, como así también de caminos de señalización del receptor de GnRH y comportamiento del tumor bajo tratamiento con drogas inmunosupresoras
