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1.
Toxicology ; 463: 152970, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34606951

RESUMEN

Intrauterine exposure to particulate matter (PM) has been associated with an increased risk of asthma development, which may differ by the age of asthma onset, sex, and pollutant concentration. To investigate the pulmonary effects of in utero exposure to concentrated urban ambient particles (CAPs) in response to house dust mite (HDM) sensitization in juvenile mice. Mice were exposed to CAPs (600 µg/m3 PM2.5) during the gestational period. Twenty-two-day postnatal mice were sensitized with HDM (100 µg, intranasally, 3 times per week). Airway responsiveness (AHR), serum immunoglobulin, and lung inflammation were assessed after 43 days of the postnatal period. Female (n = 47) and male (n = 43) mice were divided into four groups as follows: (1) FA: not exposed to CAPs; (2) CAPs: exposed to CAPs; (3) HDM: sensitized to HDM; and (4) CAPs+HDM: exposed to CAPs and HDM-sensitized. PM2.5 exposure did not worsen lung hyperresponsiveness or allergic inflammation in sensitized animals. The levels of the lung cytokines IL-4, TNF-α, and IL-2 were differentially altered in male and female animals. Males presented hyporesponsiveness and increased lung macrophagic inflammation. There were no epigenetic changes in the IL-4 gene. In conclusion, intrauterine exposure ambient PM2.5 did not worsened allergic pulmonary susceptibility but affected the pulmonary immune profile and lung function, which differed by sex.


Asunto(s)
Pulmón/inmunología , Exposición Materna/efectos adversos , Material Particulado/toxicidad , Efectos Tardíos de la Exposición Prenatal/inmunología , Animales , Citocinas/inmunología , Femenino , Inmunoglobulinas/sangre , Inmunoglobulinas/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Material Particulado/inmunología , Neumonía/inmunología , Embarazo , Pyroglyphidae/inmunología , Hipersensibilidad Respiratoria/inmunología
2.
Environ Pollut ; 253: 667-679, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31330358

RESUMEN

Many cities fail to meet air quality standards, which results in increased risk for pulmonary disorders, including asthma. Human and experimental studies have shown that diesel exhaust (DE) particles are associated with worsening of allergic asthma. Biodiesel (BD), a cleaner fuel from renewable sources, was introduced in the eighties. Because of the reduction in particulate matter (PM) emissions, BD was expected to cause fewer adverse pulmonary effects. However, only limited data on the effect of BD emissions in asthma are available. OBJECTIVE: Determine whether BD exhaust exposure in allergic sensitized mice leads to different effects on inflammatory and functional responses compared to DE exposure. METHODS: Balb/C mice were orotracheally sensitized with House Dust Mite (HDM) or a saline solution with 3 weekly instillations. From day 9 until day 17 after sensitization, they were exposed daily to filtered air (FA), DE and BD exhaust (concentration: 600 µg/m3 PM2.5). Lung function, bronchoalveolar lavage fluid (BALF) cell counts, cytokine levels (IL-2, IL-4, IL-5, IL-17, TNF-α, TSLP) in the BALF, peribronchiolar eosinophils and parenchymal macrophages were measured. RESULTS: HDM-sensitized animals presented increased lung elastance (p = 0.046), IgG1 serum levels (p = 0.029), peribronchiolar eosinophils (p = 0.028), BALF levels of total cells (p = 0.020), eosinophils (p = 0.028), IL-5 levels (p = 0.002) and TSLP levels (p = 0.046) in BALF. DE exposure alone increased lung elastance (p = 0.000) and BALF IL-4 levels (p = 0.045), whereas BD exposure alone increased BALF TSLP levels (p = 0.004). BD exposure did not influence any parameters after HDM challenge, while DE exposed animals presented increased BALF levels of total cells (p = 0.019), lymphocytes (p = 0.000), neutrophils (p = 0.040), macrophages (p = 0.034), BALF IL-4 levels (p = 0.028), and macrophagic inflammation in the lung tissue (p = 0.037), as well as decreased IgG1 (p = 0.046) and IgG2 (p = 0.043) levels when compared to the HDM group. CONCLUSION: The results indicate more adverse pulmonary effects of DE compared to BD exposure in allergic sensitized animals.


Asunto(s)
Biocombustibles/toxicidad , Emisiones de Vehículos/toxicidad , Alérgenos , Animales , Asma/inducido químicamente , Biocombustibles/análisis , Líquido del Lavado Bronquioalveolar , Citocinas , Modelos Animales de Enfermedad , Humanos , Inflamación/inducido químicamente , Interleucina-17 , Pulmón/inmunología , Ratones , Ratones Endogámicos BALB C , Neutrófilos , Material Particulado/efectos adversos , Pruebas de Toxicidad , Emisiones de Vehículos/análisis
3.
Sci Total Environ ; 628-629: 1223-1233, 2018 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-30045544

RESUMEN

Biodiesel is a renewable energy source that reduces particle emission, but few studies have assessed its effects. To assess the effects of acute inhalation of two doses (600 and 1200 µg/m3) of diesel (DE) and biodiesel (BD) fuels on the inflammatory pulmonary and systemic profile of mice. Animals were exposed for 2 h in an inhalation chamber inside the Container Laboratory for Fuels. Heart rate, heart rate variability (HRV) and blood pressure were determined 30 min after exposure. After 24 h, we analyzed the lung inflammation using bronchoalveolar lavage fluid (BALF); neutrophil and macrophage quantification in the lung parenchyma was performed, and blood and bone marrow biomarkers as well as receptor of endothelin-A (ET-Ar), receptor of endothelin-B (ET-Br), vascular cell adhesion molecule 1 (VCAM-1), inducible nitric oxide synthase (iNOs) and isoprostane (ISO) levels in the pulmonary vessels and bronchial epithelium were evaluated. HRV increased for BD600, D600 and D1200 compared to filtered air (FA). Both fuels (DE and BD) produced alterations in red blood cells independent of the dose. BALF from the BD600 and BD1200 groups showed an increase in neutrophils compared to those of the FA group. Numeric density of the polymorphonuclear and mononuclear cells was elevated with BD600 compared to FA. In the peribronchiolar vessels, there was an increase in ET-Ar and ET-Br expression following BD600 compared to FA; and there was a reduction in the iNOs expression for BD1200 and the VCAM-1 for D1200 compared to FA. In the bronchial epithelium, there was an increase in ETAr at BD600, ET-Br at two doses (600 and 1200 µg/m3) of DE and BD, iNOs at D600 and VCAM-1 at BD1200 and D600; all groups were compared to the FA group. Acute exposure to DE and BD derived from sewage methyl esters triggered pulmonary and cardiovascular inflammatory alterations in mice.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Biocombustibles/toxicidad , Neumonía/inducido químicamente , Pruebas de Toxicidad Aguda , Emisiones de Vehículos/toxicidad , Animales , Biomarcadores/metabolismo , Líquido del Lavado Bronquioalveolar , Exposición por Inhalación , Masculino , Ratones
4.
Ecotoxicol Environ Saf ; 72(1): 255-260, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18571723

RESUMEN

The present study was made to check if the Trad-MCN bioassay, developed with inflorescences of Tradescantia pallida cv. Purpurea, might discriminate genotoxic risks in areas of the city of Santo André (SE Brazil) contaminated by different air pollutants, and periods of the year when risks are higher, and to determine if the variations in the frequency of micronuclei (MCN) can be explained by environmental factors that characterize the stressful situation in each site. Potted plants were exposed in sites highly contaminated by ozone (Capuava and School) and in sites reached by high vehicular emissions (downtown and Celso Daniel Park). Pedroso Park, far from the polluted areas, was taken as reference. From September 2003 to September 2004, 20 young inflorescences were collected twice a week from each place and the frequencies of MCN were estimated. The environmental conditions observed in the polluted sites were stressful enough to promote an increase of MCN, mainly in sites reached by high vehicular emissions. But MCN rates in Capuava and at Celso Daniel Park could not be predicted only by pollutants which characterized the air contamination in these sites. More severe weather conditions, mainly low temperature, relative humidity and rainfall, caused an increase of MCN. Improvement of the biomonitoring system is recommended to minimize this negative influence of weather factors.


Asunto(s)
Monitoreo del Ambiente/métodos , Contaminación Ambiental , Mutágenos/toxicidad , Tradescantia/efectos de los fármacos , Población Urbana , Bioensayo/métodos , Brasil , Flores/efectos de los fármacos , Humanos , Humedad , Medición de Riesgo , Temperatura , Tradescantia/crecimiento & desarrollo , Emisiones de Vehículos/toxicidad , Tiempo (Meteorología)
5.
Am J Respir Crit Care Med ; 178(7): 721-8, 2008 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-18596224

RESUMEN

RATIONALE: Chronic exposure to air pollution has been associated with adverse effects on children's lung growth. OBJECTIVES: We analyzed the effects of chronic exposure to urban levels of particulate matter (PM) on selected phases of mouse lung development. METHODS: The exposure occurred in two open-top chambers (filtered and nonfiltered) placed 20 m from a street with heavy traffic in São Paulo, 24 hours/day for 8 months. There was a significant reduction of the levels of PM(2.5) inside the filtered chamber (filtered = 2.9 +/- 3.0 microg/m(3), nonfiltered = 16.8 +/- 8.3 microg/m(3); P = 0.001). At this exposure site, vehicular sources are the major components of PM(2.5) (PM

Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Exposición por Inhalación/efectos adversos , Material Particulado/efectos adversos , Alveolos Pulmonares , Animales , Brasil , Modelos Animales de Enfermedad , Femenino , Masculino , Ratones , Alveolos Pulmonares/crecimiento & desarrollo , Alveolos Pulmonares/patología , Pruebas de Función Respiratoria , Población Urbana , Emisiones de Vehículos
6.
Int J Pediatr Otorhinolaryngol ; 72(5): 581-5, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18325604

RESUMEN

OBJECTIVES: Children with cleft palate (CP) have a high prevalence of sinusitis. Considering that nasal mucus properties play a pivotal role in the upper airway defense mechanism, the aim of the study was to evaluate nasal mucus transportability and physical properties from children with CP. SETTING: Hospital for Rehabilitation of Craniofacial Anomalies, School of Dentistry, University of São Paulo, Bauru, SP, Brazil and Laboratory of Experimental Air Pollution, School of Medicine, University of São Paulo, São Paulo, SP, Brazil. METHODS: Nasal mucus samples were collected by nasal aspiration from children with CP and without CP (non-CP). Sneeze clearance (SC) was evaluated by the simulated sneeze machine. In vitro mucus transportability (MCT) by cilia was evaluated by the frog palate preparation. Mucus physical surface properties were assessed by measuring the contact angle (CA). Mucus rheology was determined by means of a magnetic rheometer, and the results were expressed as log G* (vectorial sum of viscosity and elasticity) and tan delta (relationship between viscosity and elasticity) measured at 1 and 100 rad/s. RESULTS: Mucus samples from children with CP had a higher SC than non-CP children (67+/-30 and 41+/-24 mm, respectively, p<0.05). Mucus samples from children with CP had a lower CA (24+/-16 degrees and 35+/-11 degrees , p<0.05) and a higher tan delta 100 (0.79+/-0.24 and 0.51+/-0.12, p<0.05) than non-CP children. There were no significant differences in mucus MCT, log G* 1, tan delta 1 and log G* 100 obtained for CP and non-CP children. CONCLUSIONS: Nasal mucus physical properties from children with CP are associated with higher sneeze transportability. The high prevalence of sinusitis in children with CP cannot be explained by changes in mucus physical properties and transportability.


Asunto(s)
Fisura del Paladar/fisiopatología , Depuración Mucociliar , Moco/fisiología , Mucosa Nasal/fisiopatología , Niño , Preescolar , Fisura del Paladar/cirugía , Femenino , Humanos , Técnicas In Vitro , Lactante , Masculino , Reología
7.
Braz J Otorhinolaryngol ; 73(5): 704-12, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18094814

RESUMEN

UNLABELLED: Mucociliary transport dysfunctions can impair the quality of life of patients suffering from chronic rhinossinusitis and lead to severe consequences such as alterations in respiratory physiology or even death as in cases of cystic fibrosis and primary ciliary dyskinesia. Therefore, it is crucial to understand the physiology of the mucociliary apparatus and how its components (cilia, mucus-periciliary layer and its interaction) affect the clearance of respiratory secretions. AIMS: This paper aims to review and to discuss different techniques for studying mucociliary transport and their clinical and experimental applicability. CONCLUSIONS: The methods listed in this revision provide us with valuable information about different aspects of the mucociliary transport. Some of the methods listed are more suitable for clinical practice and present reproducible results. Others, show only applicability in experimental settings due to technical difficulties or financial limitations. However, it is important to emphasize that up to now there is no method that can evaluate ciliary beating frequency (CBF) in vivo and in situ. Such a method would become a valuable tool in the scientific scenario and in the clinical practice, supporting the diagnosis of ciliary dyskinesias and avoiding the use of invasive procedures to corroborate the clinical suspicion.


Asunto(s)
Depuración Mucociliar/fisiología , Animales , Humanos , Valores de Referencia , Reología , Viscosidad
8.
Rev. bras. otorrinolaringol ; 73(5): 704-712, ago.-out. 2007. ilus
Artículo en Inglés, Portugués | LILACS | ID: lil-470454

RESUMEN

Disfunções no transporte mucociliar trazem desde queda na qualidade de vida dos pacientes, como nas rinites e rinossinusites crônicas, até graves conseqüências com risco de seqüelas irreversíveis e mesmo letais, como nos casos de fibrose cística e das discinesias ciliares primárias. Desta forma, torna-se fundamental o conhecimento do funcionamento normal do aparelho mucociliar e de como alterações em seus componentes (cílio, muco-fluido periciliar e interação dinâmica entre ambos) afetam o transporte das secreções respiratórias. OBJETIVOS: Este artigo visa a revisar e discutir as diferentes técnicas de avaliação do transporte mucociliar descrevendo suas peculiaridades e aplicabilidades clínicas e experimentais. CONCLUSÕES: Os métodos citados nesta revisão nos fornecem informações importantes sobre os diferentes aspectos do transporte mucociliar. Alguns apresentam uma maior facilidade de realização e resultados reprodutíveis, já outros apenas mostraram-se com aplicabilidade em protocolos de pesquisa em virtude de dificuldades técnicas e limitações financeiras. Há que se considerar a inexistência de métodos que avaliem ambulatorialmente a freqüência de batimento ciliar (FBC) "in vivo" e "in situ", o que se tornaria uma ferramenta importante, tanto no âmbito científico, quanto na prática clínica, auxiliando no diagnóstico das discinesias ciliares e evitando a realização de procedimentos mais invasivos para a sua confirmação diagnóstica.


Mucociliary transport dysfunctions can impair the quality of life of patients suffering from chronic rhinossinusitis and lead to severe consequences such as alterations in respiratory physiology or even death as in cases of cystic fibrosis and primary ciliary dyskinesia. Therefore, it is crucial to understand the physiology of the mucociliary apparatus and how its components (cilia, mucus-periciliary layer and its interaction) affect the clearance of respiratory secretions. AIMS: This paper aims to review and to discuss different techniques for studying mucociliary transport and their clinical and experimental applicability. CONCLUSIONS: The methods listed in this revision provide us with valuable information about different aspects of the mucociliary transport. Some of the methods listed are more suitable for clinical practice and present reproducible results. Others, show only applicability in experimental settings due to technical difficulties or financial limitations. However, it is important to emphasize that up to now there is no method that can evaluate ciliary beating frequency (CBF) in vivo and in situ. Such a method would become a valuable tool in the scientific scenario and in the clinical practice, supporting the diagnosis of ciliary dyskinesias and avoiding the use of invasive procedures to corroborate the clinical suspicion.


Asunto(s)
Animales , Humanos , Depuración Mucociliar/fisiología , Valores de Referencia , Reología , Viscosidad
9.
J Air Waste Manag Assoc ; 53(5): 574-9, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12774990

RESUMEN

Tradescantia pallida cv. purpurea, a plant species widely employed for ornamentation in Brazil, has been successfully used for monitoring the genotoxicity of various agents by the micronucleus assay. To amplify knowledge about its suitability as a bioindicator species, its capacity for accumulating trace elements from urban air pollution was evaluated. T. pallida was rooted using standardized soil, and the vases were distributed in two highly polluted sites of the urban area of São Paulo, Brazil (Cerqueira Cesar and Congonhas districts), and in one unpolluted control site situated approximately 50 km from downtown São Paulo (in Caucaia do Alto). Approximately six months after exposure to pollutants, adult leaves of this plant were collected monthly for 12 months. The leaves were washed with deionized water, dried, and ground for analyses. Characterization of element levels was carried out by neutron activation analysis. Powdered samples and standards were irradiated at the IEA-R1 nuclear reactor for short and long periods, and concentrations of As, Ba, Br, Ca, Ce, Cl, Cr, Co, Fe, K, La, Mn, Na, Rb, Sb, Sc, Sr, Th, and Zn were determined. Analysis of variance applied to the results indicated that samples from polluted sites present the highest concentrations of Ba, Ce, Cr, Co, Fe, La, Sb, and Sc (p < 0.05). Discriminant analysis revealed that it was possible to distinguish the two polluted areas with a precision of 97.5%, based on the amount of pollutant elements measured in the plants at each site. The results indicated the potential use of T. pallida as an accumulator plant for air pollution biomonitoring.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Oligoelementos/análisis , Tradescantia/química , Análisis de Activación de Neutrones
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