Donna Summer was in the places that allowed her reaching the goals she had set for herself: her d... more Donna Summer was in the places that allowed her reaching the goals she had set for herself: her debut as a singer in her church choir at the age of 10 where she replaced the vocalist who didn't show up; the role for which she auditioned and that led her to success in Europe and later to her death, as fate took her back to the United States, particularly when established her residence in New York City at the time of the fateful 9/11, an event that probably influenced the cause of her death: an aggressive lung cancer.
El presente trabajo pretende resumir la experiencia de un grupo de investigacion sobre las neumop... more El presente trabajo pretende resumir la experiencia de un grupo de investigacion sobre las neumopatias intersticiales difusas.
Mutation Research: Fundamental And Molecular Mechanisms Of Mutagenesis, Sep 1, 1997
Air pollution in the valley of Mexico is a risk to human health due to the high levels of ozone, ... more Air pollution in the valley of Mexico is a risk to human health due to the high levels of ozone, acidic sulfates, nitrogen oxides, heavy metals and polycyclic aromatic hydrocarbons present. Epidemiologic studies have found an increase incidence of adverse respiratory symptoms among the residents of Mexico City. Histopathologic changes and DNA strand breaks have been observed in the nasal
Risk factors associated with blood lead levels exceeding 15 microg/dl were analyzed in this repor... more Risk factors associated with blood lead levels exceeding 15 microg/dl were analyzed in this report. This relatively high lead level was selected because, at the time the study commenced, it was considered to be a "safe" level. A total of 1583 schoolchildren were studied. The students were from (a) two areas in Mexico City (Tlalnepantla and Xalostoc) that have had historically high concentrations of lead in air, and (b) three areas (Pedregal, Iztalpalapa, and Centro) with less impressive air lead levels. Parents were presented with a questionnaire that solicited information about lead risk factors. A bivariate analysis and a multilogistic analysis were conducted to identify associations and to identify the model that most accurately explains the variability of the sample. High blood lead concentrations were found in children who lived in Xalostoc and Tlalnepantla (16.1 and 17.0 microg/dl, respectively), and the lowest concentration (i.e., 10 microg/dl) was found in children from Iztapalapa. The strongest association was with area of residence, followed by education level of parents, cooking of meals in glazed pottery, and chewing or sucking of yellow or other colored pencils. A child's area of residence is the most significant risk factor that must be accounted for when any study of lead and blood lead concentrations is undertaken. Follow-up in similar populations should assist greatly in the evaluation of the impact of governmental actions on public health.
There is an increased interest in using biological markers to monitor individuals for possible ex... more There is an increased interest in using biological markers to monitor individuals for possible exposure to environmental toxicants. Test systems which permit the sensitive detection of DNA damage and DNA repair are critically important in such studies. The single cell gel electrophoresis (SCG) assay is a rapid and a sensitive method for the evaluation of DNA damage at the single cell level, providing information on the occurrence of DNA single-strand breaks and alkali labile sites using alkaline conditions. In this study, the differences in the basal level of DNA damage between young adults from the south (exposed principally to high levels of ozone) and young adults from the north (exposed principally to hydrocarbons and particles) of Mexico City were investigated by the SCG assay using three different cell types (leukocytes and nasal and buccal epithelial cells). We found an increased DNA migration in blood leukocytes and nasal cells from individuals who live in the southern part of the city compared to those living in the northern part; however, no differences were observed for buccal epithelial cells. These results show the feasability of using the SCG assay to evaluate DNA damage in different tissues and its great potential for use in the monitoring of humans potentially exposed to genotoxic pollutants.
Pleopeltis crassinervata (Pc) is a fern that, according to ethnobotanical records, is used in Mex... more Pleopeltis crassinervata (Pc) is a fern that, according to ethnobotanical records, is used in Mexican traditional medicine to treat gastrointestinal ailments. Recent reports indicate that the hexane fraction (Hf) obtained from Pc methanolic frond extract affects Toxoplasma gondii tachyzoite viability in vitro; therefore, in the present study, the activity of different Pc hexane subfractions (Hsf) obtained by chromatographic methods was evaluated in the same biological model. Gas chromatography/mass spectrometry (GC/MS) analysis was carried out for hexane subfraction number one (Hsf1), as it showed the highest anti-Toxoplasma activity with a half-maximal inhibitory concentration (IC50) of 23.6 µg/mL, a 50% cytotoxic concentration (CC50) of 398.7 µg/mL in Vero cells, and a selective index (SI) of 16.89. Eighteen compounds were identified by Hsf1 GC/MS analysis, with the majority being fatty acids and terpenes. Hexadecanoic acid, methyl ester was the most commonly found compound (18.05...
Resumen. En la literatura existe poca informacion con relacion a los niveles de exposicion indivi... more Resumen. En la literatura existe poca informacion con relacion a los niveles de exposicion individual a los contaminantes en la Ciudad de Mexico. Se llevo a cabo un estudio piloto para la caracterizacion de la exposicion individual de escolares al bioxido de Nitrogeno (N02). Escolares de dos zonas con niveles contrastantes de oxidantes fotoquimicos en la atmosfera fueron monitoreados utilizando tubos Palmes por una semana (equivalente 168 horas de exposicion).
Donna Summer was in the places that allowed her reaching the goals she had set for herself: her d... more Donna Summer was in the places that allowed her reaching the goals she had set for herself: her debut as a singer in her church choir at the age of 10 where she replaced the vocalist who didn't show up; the role for which she auditioned and that led her to success in Europe and later to her death, as fate took her back to the United States, particularly when established her residence in New York City at the time of the fateful 9/11, an event that probably influenced the cause of her death: an aggressive lung cancer.
El presente trabajo pretende resumir la experiencia de un grupo de investigacion sobre las neumop... more El presente trabajo pretende resumir la experiencia de un grupo de investigacion sobre las neumopatias intersticiales difusas.
Mutation Research: Fundamental And Molecular Mechanisms Of Mutagenesis, Sep 1, 1997
Air pollution in the valley of Mexico is a risk to human health due to the high levels of ozone, ... more Air pollution in the valley of Mexico is a risk to human health due to the high levels of ozone, acidic sulfates, nitrogen oxides, heavy metals and polycyclic aromatic hydrocarbons present. Epidemiologic studies have found an increase incidence of adverse respiratory symptoms among the residents of Mexico City. Histopathologic changes and DNA strand breaks have been observed in the nasal
Risk factors associated with blood lead levels exceeding 15 microg/dl were analyzed in this repor... more Risk factors associated with blood lead levels exceeding 15 microg/dl were analyzed in this report. This relatively high lead level was selected because, at the time the study commenced, it was considered to be a "safe" level. A total of 1583 schoolchildren were studied. The students were from (a) two areas in Mexico City (Tlalnepantla and Xalostoc) that have had historically high concentrations of lead in air, and (b) three areas (Pedregal, Iztalpalapa, and Centro) with less impressive air lead levels. Parents were presented with a questionnaire that solicited information about lead risk factors. A bivariate analysis and a multilogistic analysis were conducted to identify associations and to identify the model that most accurately explains the variability of the sample. High blood lead concentrations were found in children who lived in Xalostoc and Tlalnepantla (16.1 and 17.0 microg/dl, respectively), and the lowest concentration (i.e., 10 microg/dl) was found in children from Iztapalapa. The strongest association was with area of residence, followed by education level of parents, cooking of meals in glazed pottery, and chewing or sucking of yellow or other colored pencils. A child's area of residence is the most significant risk factor that must be accounted for when any study of lead and blood lead concentrations is undertaken. Follow-up in similar populations should assist greatly in the evaluation of the impact of governmental actions on public health.
There is an increased interest in using biological markers to monitor individuals for possible ex... more There is an increased interest in using biological markers to monitor individuals for possible exposure to environmental toxicants. Test systems which permit the sensitive detection of DNA damage and DNA repair are critically important in such studies. The single cell gel electrophoresis (SCG) assay is a rapid and a sensitive method for the evaluation of DNA damage at the single cell level, providing information on the occurrence of DNA single-strand breaks and alkali labile sites using alkaline conditions. In this study, the differences in the basal level of DNA damage between young adults from the south (exposed principally to high levels of ozone) and young adults from the north (exposed principally to hydrocarbons and particles) of Mexico City were investigated by the SCG assay using three different cell types (leukocytes and nasal and buccal epithelial cells). We found an increased DNA migration in blood leukocytes and nasal cells from individuals who live in the southern part of the city compared to those living in the northern part; however, no differences were observed for buccal epithelial cells. These results show the feasability of using the SCG assay to evaluate DNA damage in different tissues and its great potential for use in the monitoring of humans potentially exposed to genotoxic pollutants.
Pleopeltis crassinervata (Pc) is a fern that, according to ethnobotanical records, is used in Mex... more Pleopeltis crassinervata (Pc) is a fern that, according to ethnobotanical records, is used in Mexican traditional medicine to treat gastrointestinal ailments. Recent reports indicate that the hexane fraction (Hf) obtained from Pc methanolic frond extract affects Toxoplasma gondii tachyzoite viability in vitro; therefore, in the present study, the activity of different Pc hexane subfractions (Hsf) obtained by chromatographic methods was evaluated in the same biological model. Gas chromatography/mass spectrometry (GC/MS) analysis was carried out for hexane subfraction number one (Hsf1), as it showed the highest anti-Toxoplasma activity with a half-maximal inhibitory concentration (IC50) of 23.6 µg/mL, a 50% cytotoxic concentration (CC50) of 398.7 µg/mL in Vero cells, and a selective index (SI) of 16.89. Eighteen compounds were identified by Hsf1 GC/MS analysis, with the majority being fatty acids and terpenes. Hexadecanoic acid, methyl ester was the most commonly found compound (18.05...
Resumen. En la literatura existe poca informacion con relacion a los niveles de exposicion indivi... more Resumen. En la literatura existe poca informacion con relacion a los niveles de exposicion individual a los contaminantes en la Ciudad de Mexico. Se llevo a cabo un estudio piloto para la caracterizacion de la exposicion individual de escolares al bioxido de Nitrogeno (N02). Escolares de dos zonas con niveles contrastantes de oxidantes fotoquimicos en la atmosfera fueron monitoreados utilizando tubos Palmes por una semana (equivalente 168 horas de exposicion).
Uploads