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1.
Salud pública Méx ; 56(4): 379-385, jul.-ago. 2014. ilus, tab
Artigo em Inglês | LILACS | ID: lil-733303

RESUMO

This commentary addresses some of the diverse questions of current interest with regard to the health effects of air pollution, including exposure-response relationships, toxicity of inhaled particles and risks to health, multipollutant mixtures, traffic-related pollution, accountability research, and issues with susceptibility and vulnerability. It considers the challenges posed to researchers as they attempt to provide useful evidence for policy-makers relevant to these issues. This commentary accompanies papers giving the results from the ESCALA project, a multi-city study in Latin America that has an overall goal of providing policy-relevant results. While progress has been made in improving air quality, driven by epidemiological evidence that air pollution is adversely affecting public health, the research questions have become more subtle and challenging as levels of air pollution dropped. More research is still needed, but also novel methods and approaches to address these new questions.


Este comentario aborda algunos de los temas de interés actual en relación con los efectos de la contaminación del aire sobre la salud, tales como las relaciones exposición-respuesta, la toxicidad y riesgos para la salud de las partículas inhaladas, las mezclas de contaminantes múltiples, la contaminación relacionada con el tráfico, la investigación sobre responsabilidad, y los problemas de susceptibilidad y vulnerabilidad. Considera los retos que se presentan a los investigadores que intentan proporcionar evidencia para los responsables políticos en estas cuestiones. Este texto acompaña otros trabajos con resultados del proyecto ESCALA, un estudio en varias ciudades de América Latina que tiene como objetivo general proporcionar resultados relevantes para la política pública. Aunque ha habido avances para mejorar la calidad del aire, gracias a la evidencia epidemiológica de que la contaminación aérea está afectando negativamente a la salud pública, las preguntas de investigación se han vuelto más sutiles y difíciles a medida que los niveles de contaminación se reducen. Se necesita más investigación, pero también nuevos métodos y enfoques capaces de enfrentar estas preguntas.


Assuntos
Animais , Camundongos , Colina/análogos & derivados , Junção Neuromuscular/metabolismo , Neurotransmissores/metabolismo , Pró-Fármacos/metabolismo , Colina/metabolismo , Inibidores da Colinesterase/farmacologia , Estimulação Elétrica , Edrofônio/farmacologia , /farmacologia , Camundongos Endogâmicos , Metilaminas/farmacologia , Neostigmina/farmacologia , Fármacos Neuromusculares Despolarizantes/farmacologia , Inibidores da Captação de Neurotransmissores/farmacologia , Piperidinas/farmacologia , Rana pipiens
2.
Biol. Res ; 46(1): 47-52, 2013. ilus
Artigo em Inglês | LILACS | ID: lil-676820

RESUMO

Mechanical pressure plays an important role in many physiological and pathological processes. Mimicking the mechanical pressure present in vitro is necessary for related research, but usually requires expensive and complicated equipment. In this study we created a simple pressure culture system based on the transwell culture system. By cutting off the top rim of the transwell insert, the cells were compressed between the insert membrane and the well floor. The new pressure culture system was proven effective in that it induced cell morphological change, integrin β1 upregulation, actin polymerization and growth change in rat retinal ganglion cells, human nasopharyngeal carcinoma cells and mice embryonic fibroblasts. Though the pressure value is immeasurable and inhomogeneous, the easily available culture system still provides a choice for the laboratories that do not have access to the better, but much more expensive pressure culture equipment.


Assuntos
Animais , Humanos , Ratos , /genética , Proliferação de Células , Técnicas de Cultura de Células/métodos , Análise de Variância , Citoesqueleto de Actina/fisiologia , Linhagem Celular/fisiologia , Fibroblastos/fisiologia , Imunofluorescência/métodos , Pressão Hidrostática , Metilaminas , Neoplasias Nasofaríngeas/patologia , Cultura Primária de Células , Reação em Cadeia da Polimerase em Tempo Real , Células Ganglionares da Retina/citologia , Células Ganglionares da Retina/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Estresse Mecânico
3.
Arch. latinoam. nutr ; 53(1): 90-95, mar. 2003.
Artigo em Espanhol | LILACS | ID: lil-356581

RESUMO

Marine species muscles present non-proteins nitrogenated compounds, used as quality index. They are total volatile basis (NBVT), trimethylamine oxide (TMAO) and trimethylamine (TMA). pH is considered too as a quality index. The aim of this work was to evaluate these parameters in a fresh and canned marine product from the V region, corresponding to mora crab (Homalaspis plana). Fresh pincer meat from mora crab was extracted and kept in ice until theits analysis and thermal process of the canned product. A 3(2) statistical design was applied, considering two variables with 3 levels: 15, 30 y 45 minutes time levels: 80 degrees, 100 degrees y 121 degrees C temperature levels. Nine conditions of time-temperature were obtained. The thermal treatment caused an increase in pH and BVT. The TMA was increased since reduction of TMAO.


Assuntos
Braquiúros , Carne/análise , Temperatura Alta , Aminas/análise , Compostos de Nitrogênio/análise , Concentração de Íons de Hidrogênio , Metilaminas/análise , Músculos/química , Fatores de Tempo
4.
Braz. j. med. biol. res ; 26(4): 373-81, Apr. 1993. ilus, graf
Artigo em Inglês | LILACS | ID: lil-148748

RESUMO

In this report we analyze the kinetics of activation of the plasma membrane Ca(2+)-ATPase from kidney proximal tubules by the regulatory ligands Mg2+ and MgATP2-, and we examine modifications in the effects of these ligands that are promoted by organic solutes of natural occurrence that stabilize or destabilize protein structure and function. The solutes tested were trimethylamine-N-oxide (TMA-O), sucrose and urea. TMA-O and sucrose were chosen as representative of the different methylamines and polyols, respectively, that accumulate in living organisms. The results lead to the conclusion that free Mg2+ and the MgATP2- complex both activate the rate-determining E2-->E1 transition during the catalytic cycle of the enzyme, by binding to nonidentical and independent regulatory sites. They also indicate that TMA-O, sucrose and urea not only promote global modifications in the enzyme structure, but also modify specific interactions of the ligands Mg2+ and MgATP2- at their regulatory sites


Assuntos
Animais , Coelhos , Trifosfato de Adenosina/metabolismo , ATPases Transportadoras de Cálcio/metabolismo , Técnicas In Vitro , Magnésio/metabolismo , Túbulos Renais Proximais/enzimologia , Ativação Enzimática , ATPases Transportadoras de Cálcio/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/enzimologia , Interações Medicamentosas , Ligantes , Metilaminas/farmacologia , Oxidantes/farmacologia , Sítios de Ligação , Sacarase/farmacologia , Túbulos Renais Proximais , Ureia/farmacologia
5.
Rev. cuba. hig. epidemiol ; 22(4): 502-6, jul.-sept. 1984.
Artigo em Espanhol | LILACS | ID: lil-34956

RESUMO

Entre los precursores de la síntesis de la dimetilnitrosamina cancerígena se encuentran los nitratos, nitritos y la trimetilamina (TMA). En el presente trabajo se informan los niveles de estos precursores en 30 muestras de pescado de la especie Haemulon parra Desmarest (ronco), capturadas en la plataforma cubana. Los métodos de análisis empleados fueron: para nitratos y nitritos el recomendado por el Comité Mixto FAO/OMS en 1976 y para la trimetilamina el informado por la FAO en 1969. Los resultados obtenidos (x+ ou - S) expresados en mg/kg fueron: TMA 9,7 + ou - 6,63; NaNO3 11,7 + ou - 8,34 y NaNO2 1,0. Los niveles hallados no parecen representar un riesgo a la salud por la ingestión de estos compuestos, en comparación con otros alimentos, incluyendo otras especies de peces informados en la literatura. La posibilidad de formación de dimetilnitrosamina en las muestras analizadas a partir de los precursores estudiados es muy escasa, dados los bajos contenidos encontrados de TMA, NaNO3 y sobre todo NaNO2


Assuntos
Dimetilnitrosamina/metabolismo , Peixes , Metilaminas/análise , Nitratos/análise , Nitritos/análise
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