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1.
Cells ; 10(12)2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34944111

RESUMO

Liver fibrosis is an excessive and imbalanced deposition of fibrous extracellular matrix (ECM) that is associated with the hepatic wound-healing response. It is also the common mechanism that contributes to the impairment of the liver function that is observed in many chronic liver diseases (CLD). Despite the efforts, no effective therapy against fibrosis exists yet. Worryingly, due to the growing obesity pandemic, fibrosis incidence is on the rise. Here, we aim to summarize the main components and mechanisms involved in the progression of liver fibrosis, with special focus on the metabolic regulation of key effectors of fibrogenesis, hepatic stellate cells (HSCs), and their role in the disease progression. Hepatic cells that undergo metabolic reprogramming require a tightly controlled, fine-tuned cellular response, allowing them to meet their energetic demands without affecting cellular integrity. Here, we aim to discuss the role of ribonucleic acid (RNA)-binding proteins (RBPs), whose dynamic nature being context- and stimuli-dependent make them very suitable for the fibrotic situation. Thus, we will not only summarize the up-to-date literature on the metabolic regulation of HSCs in liver fibrosis, but also on the RBP-dependent post-transcriptional regulation of this metabolic switch that results in such important consequences for the progression of fibrosis and CLD.


Assuntos
Cirrose Hepática/metabolismo , Animais , Progressão da Doença , Células Estreladas do Fígado/metabolismo , Humanos , Modelos Biológicos , Proteínas de Ligação a RNA/metabolismo
2.
Urban Clim ; 32: 100610, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32289009

RESUMO

Rapid urbanization combined with climate change necessitates new types of urban services that make best use of science and technology. The Integrated Urban Hydro-Meteorological, Climate and Environmental Services and systems are a new initiative from the World Meteorological Organization (WMO) that seeks to provide science-based integrated urban services supporting safe, healthy and resilient cities. Various cities have already started development and implementation of such Integrated Urban Services and successfully test and use them following specific requirements of local stakeholders. This paper demonstrates the novel concept and approach of Integrated Urban Hydro-Meteorological, Climate and Environmental Services (IUS) from a set of four case study cities: Hong Kong, Toronto, Mexico City and Paris, that use different IUS configurations with good existing practice. These cities represent a range of countries, climates and geophysical settings. The aggregate main joint similarities of the IUS in these cities and synergy of the cities' experience, achievements and research findings are presented, as well as identification of existing gaps in knowledge and further research needs. A list of potential criteria for identifying and classifying IUS demonstration cities is proposed. It will aid future, more detailed analysis of the IUS experience, and selection of additional demonstration cities.

3.
Salud pública Méx ; 59(6): 630-638, nov.-dic. 2017. tab
Artigo em Espanhol | LILACS | ID: biblio-903832

RESUMO

Resumen: Objetivo: Evaluar la asociación entre la exposición a contaminantes atmosféricos y marcadores de estrés oxidativo, por un lado, y la función pulmonar, por el otro, en escolares, con y sin asma, de las ciudades de Salamanca y León, en Guanajuato, México. Material y métodos: Se realizaron determinaciones de marcadores de estrés oxidativo y pruebas de función pulmonar en 314 escolares, y se obtuvo información sobre contaminantes atmosféricos (ozono, dióxido de azufre, monóxido de carbono y partículas menores de 2.5 µm y menores de 10 µm) de las estaciones de monitoreo correspondientes. Para evaluar la asociación se corrieron modelos de regresión lineal múltiple. Resultados: Con un día de retraso a la exposición a partículas menores de 10 µm (PM10), se observó un incremento de 0.09 pmol en los dienos conjugados entre niños asmáticos de Salamanca (p<0.05). La exposición a ozono durante el mismo día incrementó la concentración de lipo-hidroperóxidos en 4.38 nmol entre asmáticos de Salamanca, así como en 2.31 nmol por la exposición a PM10 para dos días de retraso (p<0.05). La capacidad vital forzada disminuyó 138 y 203 ml en niños sin asma, respectivamente, por la exposición a monóxido de carbono (p<0.05). Conclusiones: La exposición a contaminantes atmosféricos incrementa el estrés oxidativo y disminuye la función pulmonar en escolares con y sin asma.


Abstract: Objective. To assess the association between the air pollutants exposure on markers of oxidative stress and lung function in schoolchildren with and without asthma from Salamanca and Leon Guanajuato, Mexico. Materials and methods: We realized determinations of oxidative stress biomarkers and lung function tests in 314 schoolchildren. Information of air pollutants (O3, SO2, CO, PM2.5 and PM10) were obtained from monitoring stations and multiple linear regression models were run to assess the association. Results: An increase of 0.09 pmol in conjugated dienes was observed by exposure to PM10 lag 1 in asthmatics from Salamanca (p<0.05). The exposure to O3 during the same day increased the concentration of Lipohydroperoxides in 4.38 nmol in asthmatics of Salamanca, as well as in 2.31 nmol by exposure to PM10 lag 2 (p<0.05). The forced vital capacity decreased by 138 and 203 ml in children without asthma, respectively, due to exposure to carbon monoxide (p<0.05). Conclusions: Exposure to air pollutants increase oxidative stress and decreased lung function in schoolchildren, with and without asthma.


Assuntos
Humanos , Masculino , Feminino , Criança , Asma/epidemiologia , Estresse Oxidativo , Poluição do Ar/efeitos adversos , Pulmão/fisiologia , Ozônio/efeitos adversos , Tamanho da Partícula , Espirometria , Dióxido de Enxofre/análise , Monóxido de Carbono/efeitos adversos , Biomarcadores , Modelos Lineares , Estudos Transversais , Inquéritos e Questionários , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/efeitos adversos , Exposição Ambiental
4.
Salud Publica Mex ; 59(6): 630-638, 2017.
Artigo em Espanhol | MEDLINE | ID: mdl-29451632

RESUMO

OBJECTIVE.: To assess the association between the air pollutants exposure on markers of oxidative stress and lung function in schoolchildren with and without asthma from Salamanca and Leon Guanajuato, Mexico. MATERIALS AND METHODS: We realized determinations of oxidative stress biomarkers and lung function tests in 314 schoolchildren. Information of air pollutants (O3, SO2, CO, PM2.5 and PM10) were obtained from monitoring stations and multiple linear regression models were run to assess the association. RESULTS: An increase of 0.09 pmol in conjugated dienes was observed by exposure to PM10 lag 1 in asthmatics from Salamanca (p<0.05). The exposure to O3 during the same day increased the concentration of Lipohydroperoxides in 4.38 nmol in asthmatics of Salamanca, as well as in 2.31 nmol by exposure to PM10 lag 2 (p<0.05). The forced vital capacity decreased by 138 and 203 ml in children without asthma, respectively, due to exposure to carbon monoxide (p<0.05). CONCLUSIONS: Exposure to air pollutants increase oxidative stress and decreased lung function in schoolchildren, with and without asthma.


OBJETIVO: Evaluar la asociación entre la exposición a contaminantes atmosféricos y marcadores de estrés oxidativo, por un lado, y la función pulmonar, por el otro, en escolares, con y sin asma, de las ciudades de Salamanca y León, en Guanajuato, México. MATERIAL Y MÉTODOS: Se realizaron determinaciones de marcadores de estrés oxidativo y pruebas de función pulmonar en 314 escolares, y se obtuvo información sobre contaminantes atmosféricos (ozono, dióxido de azufre, monóxido de carbono y partículas menores de 2.5 µm y menores de 10 µm) de las estaciones de monitoreo correspondientes. Para evaluar la asociación se corrieron modelos de regresión lineal múltiple. RESULTADOS: Con un día de retraso a la exposición a partículas menores de 10 µm (PM10), se observó un incremento de 0.09 pmol en los dienos conjugados entre niños asmáticos de Salamanca (p<0.05). La exposición a ozono durante el mismo día incrementó la concentración de lipo-hidroperóxidos en 4.38 nmol entre asmáticos de Salamanca, así como en 2.31 nmol por la exposición a PM10 para dos días de retraso (p<0.05). La capacidad vital forzada disminuyó 138 y 203 ml en niños sin asma, respectivamente, por la exposición a monóxido de carbono (p<0.05). CONCLUSIONES: La exposición a contaminantes atmosféricos incrementa el estrés oxidativo y disminuye la función pulmonar en escolares con y sin asma.


Assuntos
Poluição do Ar , Asma/epidemiologia , Pulmão/fisiologia , Estresse Oxidativo , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Asma/fisiopatologia , Biomarcadores , Monóxido de Carbono/efeitos adversos , Monóxido de Carbono/análise , Criança , Estudos Transversais , Exposição Ambiental , Feminino , Humanos , Modelos Lineares , Peroxidação de Lipídeos , Masculino , México , Ozônio/efeitos adversos , Ozônio/análise , Tamanho da Partícula , Espirometria , Dióxido de Enxofre/efeitos adversos , Dióxido de Enxofre/análise , Inquéritos e Questionários
5.
J Expo Sci Environ Epidemiol ; 27(3): 339-345, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27301774

RESUMO

We investigated commuter exposure to volatile organic compounds in the metropolitan area of Mexico City in 2011 in private car, microbus, bus, metro, metrobus, and trolley bus. A similar survey was conducted in 2002 before initiation of the ProAire2002-2010 program aimed at reducing air pollution. Formaldehyde, acetaldehyde, benzene, toluene, ethylbenzene, m/p-xylene, and o-xylene were sampled while traveling during the morning rush hour in May 2011. Compared with the 2002 survey, in-vehicle concentrations were substantially lower in 2011, except for formaldehyde in microbuses (35% higher than in 2002). The reductions were 17-42% (except microbuses), 25-44%, 41-61%, 43-61%, 71-79%, 80-91%, and 79-93% for formaldehyde, acetaldehyde, benzene, toluene, ethylbenzene, m/p-xylene, and o-xylene, respectively. These reductions are considered to be the outcome of some of the actions in the ProAire2002-2010 program. In some microbuses, use of liquid petroleum gas may have increased in-vehicle formaldehyde concentrations. The reduction in predicted excess cancer incidence of commuters because of ProAire2002-2010 was estimated to be 1.4 cases/yr. In addition, if every microbus commuter changed their transport mode to bus, metro, or metrobus in the future, the estimated excess cancer incidence of commuters could be further decreased from 6.4 to 0.88-2.2 cases/year.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Emissões de Veículos/análise , Emissões de Veículos/prevenção & controle , Compostos Orgânicos Voláteis/análise , Cidades , Exposição Ambiental/prevenção & controle , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Promoção da Saúde/métodos , Humanos , México/epidemiologia , Neoplasias/induzido quimicamente , Neoplasias/epidemiologia , Neoplasias/prevenção & controle
6.
Rev. colomb. biotecnol ; 18(2): 106-111, jul.-dic. 2016. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-959846

RESUMO

La Moringa oleífera es una planta que se utiliza como materia prima en diferentes industrias, como la alimentaria, farmacéutica y cosmética. Una de las partes aprovechables del árbol es la semilla debido a su contenido entre un 30 y 45 % de aceite. Sus propiedades terapéuticas potencian su uso en el tratamiento de más de 300 enfermedades. En esta investigación se caracterizó el aceite extraído de las semillas de Moringa oleífera de las variedades de origen cubano Supergenious, Plain y Nicaragua, a partir de extracciones sólido-líquido con hexano y etanol como disolventes y por el método de prensado mecánico de la variedad Nicaragua. A través de un diseño de experimento 2K se analizaron las variables relación soluto-disolvente, tiempo de extracción, y la granulometría seleccionándose las corridas con mayores valores de porcentaje de extracción. Los aceites correspondientes a la selección se caracterizaron fisicoquímica y fitoquímicamente y los valores se compararon con variedades de diferentes regiones reportadas en la literatura. Se demostró que el método de prensado es eficiente, económico y no influye en las propiedades del producto obtenido.


Moringa oleífera is a plant that is used as raw material in various industries, including those related to the field of chemistry such as food, pharmaceuticals and cosmetics. One of the usable parts of the tree is the seed because the content between 30 and 45% oil. They enhance its therapeutic use in the treatment of more than 300 diseases. In this research the oil extracted from the seeds of Moringa oleífera varieties of Cuban origin Supergenious, Plain and Nicaragua is characterized from solid-liquid extraction with hexane and ethanol as solvents and by the method of mechanical pressing of the species Nicaragua . Through a design of experiment 2K solute-solvent variable ratio, extraction time were analyzed, and the grain size selected runs with values greater percentage of oil extracted. Oils corresponding to the selection were characterized physic-chemical and phytochemically and were compared with varieties from different regions reported in the literature. It was shown that the pressing method is efficient, economical and has no influence on the product properties obtained.

7.
Acta méd. colomb ; 38(4): 268-272, oct.-dic. 2013. ilus, tab
Artigo em Espanhol | LILACS, COLNAL | ID: lil-700461

RESUMO

Resumen El mieloma de células plasmáticas secretor de IgD es una neoplasia de células plasmáticas poco frecuente, generalmente afecta individuos más jóvenes que los demás mielomas. Es de difícil diagnóstico, ya que no se observa el pico de proteína monoclonal característico de los mielomas; no obstante, la inmunofijación, la cuantificación de IgD y el estudio de orina son pruebas de gran utilidad para su diagnóstico. Con respecto a las manifestaciones clínicas, es frecuente anemia, falla renal y múltiples lesiones óseas; además, la enfermedad tiene un curso agresivo, con poca respuesta a la quimioterapia convencional. A continuación, se describe un caso de una mujer de 57 años con antecedentes de dolor óseo y múltiples lesiones líticas óseas, quien fue diagnosticada con mieloma secretor de IgD a partir de la electroforesis de proteínas en suero, la inmunofijación en suero y orina, la cuantificación de IgD y el estudio medular. (Acta Med Colomb 2013; 38: 268-272).


Abstract IgD secretory plasma cell myeloma is a rare and aggressive plasma cell neoplasm which usually affects younger individuals than other myelomas. Diagnosis is difficult since there is no monoclonal protein spike, characteristic of myelomas; however, immunofixation, IgD quantification and urine tests are useful for its diagnosis. With regard to clinical manifestations, anemia, renal failure and multiple bone lesions are frequent. In addition, the disease has an aggressive course with poor response to conventional chemotherapy. Here is reported a case of a 57 year old woman with a history of bone pain and multiple lytic bone lesions who was diagnosed with IgD secretory myeloma through serum protein electrophoresis, immunofixation in serum and urine, IgD quantification and medullary study. (Acta Med Colomb 2013; 38: 268-272).


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Mieloma Múltiplo , Imunoglobulina D , Insuficiência Renal
8.
Artigo em Inglês | MEDLINE | ID: mdl-22486663

RESUMO

One of the main problems associated with the operation of air biofilters is the loss of performance caused by drying of the bioactive support, as the removal capacity of contaminants by the microorganisms is dependent on their water content. In this work, biofilms from a microbial consortium adapted to toluene were grown on stainless steel slides. The biofilms were dried in stoppered flasks with saturated saline solutions to obtain final water activities of 97.4 %, 83.9 %, 74.8 % and 32 %. The biofilms were characterized by a sorption isotherm Type III with toluene; the water desorption isotherm was fitted to the BET model and the biofilm hydrophobicity was also determined. Specific oxygen consumption rates decreased at lower Aw from 60 µg O(2)/mg protein/h to zero activity. Biofilm activity, represented by a toluene consumption rate, and others physical properties presented a critical point between Aw 0.84 and 0.97. Biological activity of dried biofilms was restored either partially or completely, depending on the extent of drying and rewetting method.


Assuntos
Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , Reatores Biológicos/microbiologia , Filtração , Leveduras/metabolismo , Poluentes Atmosféricos/metabolismo , Poluição do Ar/prevenção & controle , Biodegradação Ambiental , Ionização de Chama , Umidade , Interações Hidrofóbicas e Hidrofílicas , Espectrofotometria , Aço Inoxidável/química , Tolueno/metabolismo , Água/química
9.
Environ Sci Technol ; 42(17): 6502-7, 2008 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-18800521

RESUMO

Relatively little is known about the lanthanoid element (La to Lu) chemistry of inhalable urban atmospheric particulate matter (PM). PM samples collected during an air sampling campaign in the Mexico City area contain lanthanoid concentrations of mostly 1-10 ng m(-3), increasing with mass where resuspension of crustal PM is important (low PM2.5/PM10), but not where fine emissions from traffic and industry dominate (high PM2.5/ PM10). Samples show anthropogenic enrichment of lighter over heavier lanthanoids, and Ce enrichment relative to La and Sm occurs in the city center (especially PM10) possibly due to PM from road vehicle catalytic converters. La is especially enriched, although many samples show low La/V values (< 0.11), suggesting the dominating influence of fuel oil combustion sources rather than refinery emissions. We use La/Sm v La/ Ce, LaCeSm, and LaCeV plots to compare Mexico City aerosols with PM from other cities. Lanthanoid aerosol geochemistry can be used not only to identify refinery pollution events, but also as a marker for different hydrocarbon combustion emissions (e.g., oil or coal power stations) on urban background atmospheric PM.


Assuntos
Poluentes Atmosféricos/química , Atmosfera , Elementos da Série dos Lantanídeos/química , Saúde da População Urbana , Cério/química , México
10.
Dermatol. rev. mex ; 38(3): 174-7, mayo-jun. 1994. tab
Artigo em Espanhol | LILACS | ID: lil-143266

RESUMO

En nueve pacientes con melasma idiopática se encontraron niveles bajos de gonadotropinas y altos niveles de estrógenos en la folicular, así como también niveles bajos de progesterona en la fase lútea, cuando se compararon con pacientes controles. Estos resultados estuvieron de acuerdo con observaciones previas de la melasma en estados caracterizados por altos niveles de estrógenos tales como el embarazo y el uso de anticonceptivos hormonales. Es posible que estos pacientes tengan moderada disfunción ovárica (subclínica). Ya que los estrógenos están involucrados en el proceso pigmentario, es posible que esta anormalidad esté relacionada a la patogénesis del melasma idiopático


Assuntos
Humanos , Feminino , Adulto , Estrogênios/análise , Estrogênios , Gonadotropinas/análise , Gonadotropinas/deficiência , Melanose/diagnóstico , Melanose/fisiopatologia , Progesterona/análise , Progesterona/deficiência
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