Victor Castillo | Universidad de Santiago de Chile (original) (raw)
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Papers by Victor Castillo
Endocrinology, 2006
Cushing&a... more Cushing's disease is almost always caused by an ACTH-secreting pituitary tumor, but effective medical therapy is currently limited. Because retinoic acid has been shown to be potentially useful in decreasing corticotroph secretion and proliferation in rodent models, we have studied its action in dogs with Cushing's disease. A randomized treatment with retinoic acid (n = 22) vs. ketoconazole (n = 20) in dogs with Cushing's disease was assigned for a period of 180 d. Clinical signs, plasma ACTH and alpha-MSH, the cortisol/creatinine urine ratio, and pituitary magnetic resonance imaging were assessed and compared at different time points. We recorded a significant reduction in plasma ACTH and alpha-MSH, and also in the cortisol/creatinine urine ratio, of the dogs treated with retinoic acid. Pituitary adenoma size was also significantly reduced at the end of retinoic acid treatment. Survival time and all the clinical signs evaluated showed an improvement in the retinoic-acid-treated dogs. No adverse events or signs of hepatotoxicity were observed, suggesting that the drug is not only effective but also safe. Retinoic acid treatment controls ACTH and cortisol hyperactivity and tumor size in dogs with ACTH-secreting tumors, leading to resolution of the clinical phenotype. This study highlights the possibility of using retinoic acid as a novel therapy in the treatment of ACTH-secreting tumors in humans with Cushing's disease.
Cushing&a... more Cushing's disease is almost always caused by an ACTH-secreting pituitary tumor, but effective medical therapy is currently limited. Because retinoic acid has been shown to be potentially useful in decreasing corticotroph secretion and proliferation in rodent models, we have studied its action in dogs with Cushing's disease. A randomized treatment with retinoic acid (n = 22) vs. ketoconazole (n = 20) in dogs with Cushing's disease was assigned for a period of 180 d. Clinical signs, plasma ACTH and alpha-MSH, the cortisol/creatinine urine ratio, and pituitary magnetic resonance imaging were assessed and compared at different time points. We recorded a significant reduction in plasma ACTH and alpha-MSH, and also in the cortisol/creatinine urine ratio, of the dogs treated with retinoic acid. Pituitary adenoma size was also significantly reduced at the end of retinoic acid treatment. Survival time and all the clinical signs evaluated showed an improvement in the retinoic-acid-treated dogs. No adverse events or signs of hepatotoxicity were observed, suggesting that the drug is not only effective but also safe. Retinoic acid treatment controls ACTH and cortisol hyperactivity and tumor size in dogs with ACTH-secreting tumors, leading to resolution of the clinical phenotype. This study highlights the possibility of using retinoic acid as a novel therapy in the treatment of ACTH-secreting tumors in humans with Cushing's disease.
American Journal of Therapeutics, 2008
The prevalence of cardiovascular diseases (CVD) and diabetes mellitus type 2 (DM 2) is decreasing... more The prevalence of cardiovascular diseases (CVD) and diabetes mellitus type 2 (DM 2) is decreasing in developed countries despite the increase in the percentage of subjects with obesity and other well-recognized cardiovascular risk factors. In contrast, the recent transition of the economic model experienced by developing countries, characterized by the adoption of a Western lifestyle, that we have named "socioeconomic pathology," has led to an increase in the burden of CVD. It has been demonstrated that conventional cardiovascular risk factors in developed and developing countries are the same. Why then does the population of developing countries currently have a higher incidence of CVD than that of developed countries if they share the same risk factors? We have proposed the existence of a higher susceptibility to the development of systemic inflammation at low levels of abdominal obesity in the population of developing countries and the consequent endothelial dysfunction, insulin resistance, DM 2, and CVD. In contrast, an important percentage of obese people living in developed countries have a healthy phenotype and low risk of developing CVD and DM 2. Human epidemiologic studies and experimental dietary interventions in animal models have provided considerable evidence to suggest that nutritional imbalance and metabolic disturbances early in life may later have a persistent effect on an adult's health that may even be transmitted to the next generations. Epigenetic changes dependent on nutrition could be key in this evolutionary health behavior, acting as a buffering system, permitting the adaptation to environmental conditions by silencing or increasing the expression of certain genes.
Soil Science Society of America Journal, 1998
... as a mea-sure of microbial activity in soil, although some re-searchers have criticized this ... more ... as a mea-sure of microbial activity in soil, although some re-searchers have criticized this hypothesis (Nannipieri et al., 1990; Beyer et al ... plant residues (Hayano and Tubaki, 1985), which contributes to the release of energy for soil microbial activity (Eivazi and Zakaria, 1993). ...
Soil Biology & Biochemistry, 2000
Soil amendment with organic materials prior to aorestation as well as the use of mycorrhizal inoc... more Soil amendment with organic materials prior to aorestation as well as the use of mycorrhizal inoculation, are advisable practices in aorestation of semiarid areas. In this work, the eect of both organic amendment and mycorrhizal treatment on the microbial activity of a soil aorested with Aleppo pine (Pinus halepensis Miller) was studied. Labile carbon fractions (water soluble carbon and water soluble carbohydrates), microbiological parameters (microbial biomass carbon, basal respiration and metabolic quotient), and enzyme activities such as oxydoreductases (deshydrogenase and catalase activities) and hydrolases (urease, protease and phosphatase) were determined. All these parameters were found positively in¯uenced by organic amendment and mycorrhizal treatment of plant roots by inoculation of fungi or forest soil addition. The best result was obtained when mycorrhizal inoculation with fungi was supplemented by organic amendment. 7
Annals of Forest Science, 1996
... amendments A Roldán, I Querejeta J Albaladejo, V Castillo Centro ... analyser. Avail-able P w... more ... amendments A Roldán, I Querejeta J Albaladejo, V Castillo Centro ... analyser. Avail-able P was extracted with sodium bicarbonate (Olsen et al, 1954) and determined by colori-metry according to Murphy and Riley (1962). K ...
Soil amendment with organic materials prior to aorestation as well as the use of mycorrhizal inoc... more Soil amendment with organic materials prior to aorestation as well as the use of mycorrhizal inoculation, are advisable practices in aorestation of semiarid areas. In this work, the eect of both organic amendment and mycorrhizal treatment on the microbial activity of a soil aorested with Aleppo pine (Pinus halepensis Miller) was studied. Labile carbon fractions (water soluble carbon and water soluble carbohydrates), microbiological parameters (microbial biomass carbon, basal respiration and metabolic quotient), and enzyme activities such as oxydoreductases (deshydrogenase and catalase activities) and hydrolases (urease, protease and phosphatase) were determined. All these parameters were found positively in¯uenced by organic amendment and mycorrhizal treatment of plant roots by inoculation of fungi or forest soil addition. The best result was obtained when mycorrhizal inoculation with fungi was supplemented by organic amendment. 7
Soil Use and Management, 1998
Abstract. The fragile soils at the transition between semiarid and arid areas are continuously th... more Abstract. The fragile soils at the transition between semiarid and arid areas are continuously threatened by human activity, which frequently involves the elimination of plant cover. We studied the impact of vegetation removal on soil characteristics in senmiarid Mediterranean Spain using two plots (15 m ± 5 m), installed on a north facing slope of 23%. Vegetation was removed from one of the plots (disturbed plot), and changes in the soil characteristics were compared with an undisturbed control plot. Fifty-five months after vegetation removal the organic carbon content decreased by 35%, the percentage of stable aggregates by 31% and soil bulk density increased by 8%. The models that best represented the changes of these parameters with time were linear equations. There were no significant differences between the water retention capacity or saturated hydraulic conductivity of the treatments. The rapid loss of soil organic matter and the consequences in terms of physical soil properties were considered to be the main factors in soil degradation. No symptoms of natural recovery were observed in the disturbed plot and the tendency was for a steady deterioration in soil behaviour. This means that human activity or climatic change leading to less vegetation could result in irreversible soil degradation in semiarid areas.
Plant and Soil, 1996
A field experiment was carried out to evaluate the growth response of Pinus halepensis seedlings ... more A field experiment was carried out to evaluate the growth response of Pinus halepensis seedlings inoculated with Pisolithus arhizus and planted in a terraced rangeland amended with urban solid refuse. The application of the organic amendment mediated a significant increase in soil fertility and soil water content. Twenty seven months after planting seedling survival rates did not differ significantly among treatments and were above 95% in all cases. Growth of P. halepensis was significantly (pP. arhizus also significantly (pP. arhizus inoculation significantly improved the performance of Pinus halepensis, and this methodology could be successfully applied in afforestation programmes in semiarid and degraded sites.
Archivos De Medicina Veterinaria, 1997
Básicamente, un economista tiene el mismo aspecto que el científico. Y, sin duda, este texto plan... more Básicamente, un economista tiene el mismo aspecto que el científico. Y, sin duda, este texto plantea la economía como una ciencia: como una estructura de modelos (teorías) que explican el mundo real. En términos más específicos la economía es una ciencia social; pretende explicar cómo actúan los seres humanos entre sí.
Endocrinology, 2006
Cushing&a... more Cushing's disease is almost always caused by an ACTH-secreting pituitary tumor, but effective medical therapy is currently limited. Because retinoic acid has been shown to be potentially useful in decreasing corticotroph secretion and proliferation in rodent models, we have studied its action in dogs with Cushing's disease. A randomized treatment with retinoic acid (n = 22) vs. ketoconazole (n = 20) in dogs with Cushing's disease was assigned for a period of 180 d. Clinical signs, plasma ACTH and alpha-MSH, the cortisol/creatinine urine ratio, and pituitary magnetic resonance imaging were assessed and compared at different time points. We recorded a significant reduction in plasma ACTH and alpha-MSH, and also in the cortisol/creatinine urine ratio, of the dogs treated with retinoic acid. Pituitary adenoma size was also significantly reduced at the end of retinoic acid treatment. Survival time and all the clinical signs evaluated showed an improvement in the retinoic-acid-treated dogs. No adverse events or signs of hepatotoxicity were observed, suggesting that the drug is not only effective but also safe. Retinoic acid treatment controls ACTH and cortisol hyperactivity and tumor size in dogs with ACTH-secreting tumors, leading to resolution of the clinical phenotype. This study highlights the possibility of using retinoic acid as a novel therapy in the treatment of ACTH-secreting tumors in humans with Cushing's disease.
Cushing&a... more Cushing's disease is almost always caused by an ACTH-secreting pituitary tumor, but effective medical therapy is currently limited. Because retinoic acid has been shown to be potentially useful in decreasing corticotroph secretion and proliferation in rodent models, we have studied its action in dogs with Cushing's disease. A randomized treatment with retinoic acid (n = 22) vs. ketoconazole (n = 20) in dogs with Cushing's disease was assigned for a period of 180 d. Clinical signs, plasma ACTH and alpha-MSH, the cortisol/creatinine urine ratio, and pituitary magnetic resonance imaging were assessed and compared at different time points. We recorded a significant reduction in plasma ACTH and alpha-MSH, and also in the cortisol/creatinine urine ratio, of the dogs treated with retinoic acid. Pituitary adenoma size was also significantly reduced at the end of retinoic acid treatment. Survival time and all the clinical signs evaluated showed an improvement in the retinoic-acid-treated dogs. No adverse events or signs of hepatotoxicity were observed, suggesting that the drug is not only effective but also safe. Retinoic acid treatment controls ACTH and cortisol hyperactivity and tumor size in dogs with ACTH-secreting tumors, leading to resolution of the clinical phenotype. This study highlights the possibility of using retinoic acid as a novel therapy in the treatment of ACTH-secreting tumors in humans with Cushing's disease.
American Journal of Therapeutics, 2008
The prevalence of cardiovascular diseases (CVD) and diabetes mellitus type 2 (DM 2) is decreasing... more The prevalence of cardiovascular diseases (CVD) and diabetes mellitus type 2 (DM 2) is decreasing in developed countries despite the increase in the percentage of subjects with obesity and other well-recognized cardiovascular risk factors. In contrast, the recent transition of the economic model experienced by developing countries, characterized by the adoption of a Western lifestyle, that we have named "socioeconomic pathology," has led to an increase in the burden of CVD. It has been demonstrated that conventional cardiovascular risk factors in developed and developing countries are the same. Why then does the population of developing countries currently have a higher incidence of CVD than that of developed countries if they share the same risk factors? We have proposed the existence of a higher susceptibility to the development of systemic inflammation at low levels of abdominal obesity in the population of developing countries and the consequent endothelial dysfunction, insulin resistance, DM 2, and CVD. In contrast, an important percentage of obese people living in developed countries have a healthy phenotype and low risk of developing CVD and DM 2. Human epidemiologic studies and experimental dietary interventions in animal models have provided considerable evidence to suggest that nutritional imbalance and metabolic disturbances early in life may later have a persistent effect on an adult's health that may even be transmitted to the next generations. Epigenetic changes dependent on nutrition could be key in this evolutionary health behavior, acting as a buffering system, permitting the adaptation to environmental conditions by silencing or increasing the expression of certain genes.
Soil Science Society of America Journal, 1998
... as a mea-sure of microbial activity in soil, although some re-searchers have criticized this ... more ... as a mea-sure of microbial activity in soil, although some re-searchers have criticized this hypothesis (Nannipieri et al., 1990; Beyer et al ... plant residues (Hayano and Tubaki, 1985), which contributes to the release of energy for soil microbial activity (Eivazi and Zakaria, 1993). ...
Soil Biology & Biochemistry, 2000
Soil amendment with organic materials prior to aorestation as well as the use of mycorrhizal inoc... more Soil amendment with organic materials prior to aorestation as well as the use of mycorrhizal inoculation, are advisable practices in aorestation of semiarid areas. In this work, the eect of both organic amendment and mycorrhizal treatment on the microbial activity of a soil aorested with Aleppo pine (Pinus halepensis Miller) was studied. Labile carbon fractions (water soluble carbon and water soluble carbohydrates), microbiological parameters (microbial biomass carbon, basal respiration and metabolic quotient), and enzyme activities such as oxydoreductases (deshydrogenase and catalase activities) and hydrolases (urease, protease and phosphatase) were determined. All these parameters were found positively in¯uenced by organic amendment and mycorrhizal treatment of plant roots by inoculation of fungi or forest soil addition. The best result was obtained when mycorrhizal inoculation with fungi was supplemented by organic amendment. 7
Annals of Forest Science, 1996
... amendments A Roldán, I Querejeta J Albaladejo, V Castillo Centro ... analyser. Avail-able P w... more ... amendments A Roldán, I Querejeta J Albaladejo, V Castillo Centro ... analyser. Avail-able P was extracted with sodium bicarbonate (Olsen et al, 1954) and determined by colori-metry according to Murphy and Riley (1962). K ...
Soil amendment with organic materials prior to aorestation as well as the use of mycorrhizal inoc... more Soil amendment with organic materials prior to aorestation as well as the use of mycorrhizal inoculation, are advisable practices in aorestation of semiarid areas. In this work, the eect of both organic amendment and mycorrhizal treatment on the microbial activity of a soil aorested with Aleppo pine (Pinus halepensis Miller) was studied. Labile carbon fractions (water soluble carbon and water soluble carbohydrates), microbiological parameters (microbial biomass carbon, basal respiration and metabolic quotient), and enzyme activities such as oxydoreductases (deshydrogenase and catalase activities) and hydrolases (urease, protease and phosphatase) were determined. All these parameters were found positively in¯uenced by organic amendment and mycorrhizal treatment of plant roots by inoculation of fungi or forest soil addition. The best result was obtained when mycorrhizal inoculation with fungi was supplemented by organic amendment. 7
Soil Use and Management, 1998
Abstract. The fragile soils at the transition between semiarid and arid areas are continuously th... more Abstract. The fragile soils at the transition between semiarid and arid areas are continuously threatened by human activity, which frequently involves the elimination of plant cover. We studied the impact of vegetation removal on soil characteristics in senmiarid Mediterranean Spain using two plots (15 m ± 5 m), installed on a north facing slope of 23%. Vegetation was removed from one of the plots (disturbed plot), and changes in the soil characteristics were compared with an undisturbed control plot. Fifty-five months after vegetation removal the organic carbon content decreased by 35%, the percentage of stable aggregates by 31% and soil bulk density increased by 8%. The models that best represented the changes of these parameters with time were linear equations. There were no significant differences between the water retention capacity or saturated hydraulic conductivity of the treatments. The rapid loss of soil organic matter and the consequences in terms of physical soil properties were considered to be the main factors in soil degradation. No symptoms of natural recovery were observed in the disturbed plot and the tendency was for a steady deterioration in soil behaviour. This means that human activity or climatic change leading to less vegetation could result in irreversible soil degradation in semiarid areas.
Plant and Soil, 1996
A field experiment was carried out to evaluate the growth response of Pinus halepensis seedlings ... more A field experiment was carried out to evaluate the growth response of Pinus halepensis seedlings inoculated with Pisolithus arhizus and planted in a terraced rangeland amended with urban solid refuse. The application of the organic amendment mediated a significant increase in soil fertility and soil water content. Twenty seven months after planting seedling survival rates did not differ significantly among treatments and were above 95% in all cases. Growth of P. halepensis was significantly (pP. arhizus also significantly (pP. arhizus inoculation significantly improved the performance of Pinus halepensis, and this methodology could be successfully applied in afforestation programmes in semiarid and degraded sites.
Archivos De Medicina Veterinaria, 1997
Básicamente, un economista tiene el mismo aspecto que el científico. Y, sin duda, este texto plan... more Básicamente, un economista tiene el mismo aspecto que el científico. Y, sin duda, este texto plantea la economía como una ciencia: como una estructura de modelos (teorías) que explican el mundo real. En términos más específicos la economía es una ciencia social; pretende explicar cómo actúan los seres humanos entre sí.