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1.
Biol Res ; 52(1): 55, 2019 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-31601259

RESUMEN

BACKGROUND: Epanorin (EP) is a secondary metabolite of the Acarospora lichenic species. EP has been found in lichenic extracts with antimicrobial activity, and UV-absorption properties have been described for closely related molecules; however, its antiproliferative activity in cancer cells has not yet been explored. It has been hypothesized that EP inhibits cancer cell growth. MCF-7 breast cancer cells, normal fibroblasts, and the non-transformed HEK-293 cell line were exposed to increasing concentrations of EP, and proliferation was assessed by the sulforhodamine-B assay. RESULTS: MCF-7 cells exposed to EP were examined for cell cycle progression using flow cytometry, and DNA fragmentation was examined using the TUNEL assay. In addition, EP's mutagenic activity was assessed using the Salmonella typhimurium reverse mutation assay. The data showed that EP inhibits proliferation of MCF-7 cells, and it induces cell cycle arrest in G0/G1 through a DNA fragmentation-independent mechanism. Furthermore, EP's lack of overt cytotoxicity in the normal cell line HEK-293 and human fibroblasts in cell culture is supported by the absence of mutagenic activity of EP. CONCLUSION: EP emerges as a suitable molecule for further studies as a potential antineoplastic agent.


Asunto(s)
Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Proliferación Celular/efectos de los fármacos , Líquenes/química , Antineoplásicos/aislamiento & purificación , Fragmentación del ADN , Femenino , Citometría de Flujo , Humanos , Células MCF-7
2.
Rev Environ Contam Toxicol ; 223: 1-31, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23149810

RESUMEN

The use of statistical distributions to predict air quality is valuable for determining the impact of air chemical contaminants on human health. Concentrations of air pollutants are treated as random variables that can be modeled by a statistical distribution that is positively skewed and starts from zero. The type of distribution selected for analyzing air pollution data and its associated parameters depend on factors such as emission source and local meteorology and topography. International environmental guideline use appropriate distributions to compute exceedance probabilities and percentiles for setting administrative targets and issuing environmental alerts. The distribution bears a relationship to the normal distribution, and there are theoretical - and physical-based mechanistic arguments that support its use when analyzing air-pollutant data. Others distribution have also been used to model air population data, such as the beta, exponential, gamma, Johnson, log-logistic, Pearson, and Weibull distribution. One model also developed from physical-mechanistic considerations that has received considerable interest in recent year is the Birnbaum-Saunders distribution. This distribution has theoretical arguments and properties similar to those of the log-normal distribution, which renders it useful for modeling air contamination data. In this review, we have addressed the range of common atmospheric contaminants and the health effects they cause. We have also reviewed the statistical distributions that have been use to model air quality, after which we have detailed the problem of air contamination in Santiago, Chile. We have illustrated a methodology that is based on the Birnbaum-Saunders distributions to analyze air contamination data from Santiago, Chile. Finally, in the conclusions, we have provided a list of synoptic statements designed to help readers understand the significance of air pollution in Chile, and in Santiago, in particular, but that can be useful to other cites and countries.


Asunto(s)
Contaminantes Atmosféricos/química , Tamaño de la Partícula , Contaminantes Atmosféricos/toxicidad , Chile , Humanos
3.
Rev Med Chil ; 139(5): 613-7, 2011 May.
Artículo en Español | MEDLINE | ID: mdl-22051712

RESUMEN

BACKGROUND: Approximately 15% of misoprostol-induced-abortions may not be successful, leading to in utero exposure to the drug and to the induction of a series of defects including central nervous system, limb and visceral defects. A common proposal is that the drug causes disruption of the fetal vasculature leading to embryonic or fetal hypoxia. AIM: To evaluate the teratogenicity of misoprostol using the rat post-implantation embryo culture. MATERIAL AND METHODS: Rat embryos were collected at the beginning of organogenesis and cultured in rat serum containing misoprostol at concentrations of 200, 2,000 or 20,000 pg/ml. Functionality, morphology and morphometry parameters were evaluated. RESULTS: Misoprostol induced a dose-dependent embryotoxic effect causing a decrease in embryo viability and function (poor vascular development and survival) and morphometry (alterations in branchial arches, heart and cephalic portions of the neural tube, among others). CONCLUSIONS: All the manifestations observed are indicative of the ability of misoprostol to directly induce developmental retardation and alterations.


Asunto(s)
Anomalías Inducidas por Medicamentos/embriología , Abortivos no Esteroideos/toxicidad , Embrión de Mamíferos/efectos de los fármacos , Misoprostol/toxicidad , Animales , Embrión de Mamíferos/anomalías , Femenino , Pruebas de Mutagenicidad/métodos , Embarazo , Ratas , Ratas Sprague-Dawley
4.
Biol. Res ; 52: 55-55, 2019. ilus, graf, tab
Artículo en Inglés | LILACS | ID: biblio-1505775

RESUMEN

BACKGROUND: Epanorin (EP) is a secondary metabolite of the Acarospora lichenic species. EP has been found in lichenic extracts with antimicrobial activity, and UV-absorption properties have been described for closely related molecules; however, its antiproliferative activity in cancer cells has not yet been explored. It has been hypothesized that EP inhibits cancer cell growth. MCF-7 breast cancer cells, normal fibroblasts, and the non-transformed HEK-293 cell line were exposed to increasing concentrations of EP, and proliferation was assessed by the sulforhodamine-B assay. RESULTS: MCF-7 cells exposed to EP were examined for cell cycle progression using flow cytometry, and DNA fragmentation was examined using the TUNEL assay. In addition, EP's mutagenic activity was assessed using the Salmonella typhimurium reverse mutation assay. The data showed that EP inhibits proliferation of MCF-7 cells, and it induces cell cycle arrest in G0/G1 through a DNA fragmentation-independent mechanism. Furthermore, EP's lack of overt cytotoxicity in the normal cell line HEK-293 and human fibroblasts in cell culture is supported by the absence of mutagenic activity of EP. CONCLUSION: EP emerges as a suitable molecule for further studies as a potential antineoplastic agent.


Asunto(s)
Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Líquenes/química , Antineoplásicos/uso terapéutico , Fragmentación del ADN , Células MCF-7 , Citometría de Flujo , Antineoplásicos/aislamiento & purificación
5.
Rev. méd. Chile ; 139(5): 613-617, mayo 2011. ilus, tab
Artículo en Español | LILACS | ID: lil-603098

RESUMEN

Background: Approximately 15 percent of misoprostol-induced-abortions may not be successful, leading to in utero exposure to the drug and to the induction of a series of defects including central nervous system, limb and visceral defects. A commonproposal is that the drug causes disruption of the fetal vasculature leading to embryonic or fetal hypoxia. Aim: To evaluate the teratogenicity of misoprostol using the rat post-implantation embryo culture. Material and Methods: Rat embryos were collected at the beginning of organogenesis and cultured in rat serum containing misoprostol at concentrations of 200, 2,000 or 20,000 pg/ml. Functionality, morphology and morphometry parameters were evaluated. Results: Misoprostol induced a dose-dependent embryotoxic effect causing a decrease in embryo viability and function (poor vascular development and survival) and morphometry (alterations in branchial arches, heart and cephalic portions of the neural tube, among others). Conclusions: All the manifestations observed are indicative of the ability of misoprostol to directly induce developmental retardation and alterations.


Asunto(s)
Animales , Femenino , Embarazo , Ratas , Anomalías Inducidas por Medicamentos/embriología , Abortivos no Esteroideos/toxicidad , Embrión de Mamíferos/efectos de los fármacos , Misoprostol/toxicidad , Embrión de Mamíferos/anomalías , Pruebas de Mutagenicidad/métodos , Ratas Sprague-Dawley
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