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1.
Lupus ; 30(14): 2268-2275, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34879788

RESUMEN

OBJECTIVE: To assess the effect of individual exposure, in real-time, to traffic-related pollutants on serum interleukin levels of childhood-onset lupus erythematous systemic (c-SLE) patients. METHODS: A longitudinal and observational design was conducted in 12 repeated measures of serum samples and clinical evaluations (totaling 108 measurements) of c-SLE patients over 30 consecutive months. Real-time, individual exposure to fine particles (PM2.5) and nitrogen dioxide (NO2) was measured with portable monitors. Generalized estimating equation was used to evaluate the association between exposure to PM2.5 and NO2 and the following serum cytokine levels on the 7 days preceding clinical assessment and serum collection: MCP1, IL-6, IL-8, IL-10, IL-17, IFN-alpha, and TNF-alpha. Disease activity and other risk factors were also controlled. RESULTS: An interquartile range (IQR) increase in PM2.5 daily concentration was significantly associated with increased levels of TNF-alpha on the third, fourth, and seventh day after exposure; IL-10 on the third and fourth day after exposure; IL-17 on the third and seventh day after exposure; and INF-alpha on the third day after exposure (p < 0.05). An IQR increase in 7-day moving average of PM2.5 was associated with a 6.2 pg/mL (95% CI: 0.5; 11.8; p = 0.04) increase in serum IFN-alpha level. An unexpected significant association was observed between an IQR increase in NO27-day cumulative concentration and a decrease of 1.6 pg/mL (95% CI: -2.6; -0.7; p < 0.001) in serum IL-17. CONCLUSION: Real-time exposure to PM2.5 prospectively associated with increased serum TNF-alpha, INF-alpha, IL-10, and IL-17 levels in c-SLE patients.


Asunto(s)
Contaminación del Aire , Lupus Eritematoso Discoide , Lupus Eritematoso Sistémico , Contaminación del Aire/análisis , Humanos , Interferón-alfa/inmunología , Interleucina-10/inmunología , Interleucina-17/inmunología , Dióxido de Nitrógeno , Material Particulado/efectos adversos , Estudios Prospectivos , Factor de Necrosis Tumoral alfa
2.
Pediatr Nephrol ; 35(7): 1247-1255, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32346765

RESUMEN

BACKGROUND: Childhood-onset systemic lupus erythematosus (cSLE) is an autoimmune and multifactorial disease that can affect the renal system. Exposure to air pollution can trigger systemic inflammation in cSLE patients and increase risk of disease activity. We evaluated effects of individual real-time exposure to air pollutants on renal activity in cSLE patients using the Systemic Lupus Erythematosus Disease Activity Index 2000. METHODS: Longitudinal panel study of 108 repetitive measures from 9 pediatric lupus patients. Over three consecutive weeks, daily individual levels of fine particulate matter (PM2.5) and nitrogen dioxide (NO2) were measured, as well as weekly clinical evaluation and laboratory tests. This was repeated every 10 weeks over a 1-year period. Specific generalized estimating equation models were used to evaluate the impact of these pollutants on risk of nephritis and anti-dsDNA > 20 UI/mL and on 24-h urine protein and serum complement (C3) levels. RESULTS: An interquartile range (IQR) increase of 18.12 µg/m3 in PM2.5 daily concentration was associated with increased risk of nephritis and positive results for anti-dsDNA. Moreover, increase in 24-h urine protein and decrease in C3 serum levels also associated with exposure to pollutants. An IQR increase in PM2.57-day moving average was associated with increased risks of leukocyturia (3.4; 95% CI 2.6:4.3), positive anti-dsDNA (3.1; 95% CI 2.1:4.0), and 36.3-mg increase (95% IC 20.2:52.3) in 24-h urine protein. An IQR increase (63.1 µg/m3) in 7-day cumulative NO2 levels was associated with decreased serum C3 levels. CONCLUSIONS: This prospective study suggests exposure to air pollution can trigger renal activity in cSLE patients.


Asunto(s)
Contaminación del Aire/efectos adversos , Riñón/fisiopatología , Lupus Eritematoso Sistémico/metabolismo , Material Particulado/efectos adversos , Adolescente , Contaminación del Aire/análisis , Contaminación del Aire/estadística & datos numéricos , Brasil , Niño , Preescolar , Monitoreo del Ambiente , Femenino , Humanos , Estudios Longitudinales , Masculino , Estudios Prospectivos , Medición de Riesgo
4.
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
5.
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
6.
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
7.
Clin Rheumatol ; 37(3): 683-690, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29098476

RESUMEN

Exposure to fine particles may trigger pulmonary inflammation/systemic inflammation. The objective of this study was to investigate the association between daily individual exposure to air pollutants and airway inflammation and disease activity in childhood-onset systemic lupus erythematosus (cSLE) patients. A longitudinal panel study was carried out in 108 consecutive appointments with cSLE patients without respiratory diseases. Over four consecutive weeks, daily individual measures of nitrogen dioxide (NO2), fine particulate matter (PM2.5), ambient temperature, and humidity were obtained. This cycle was repeated every 2.5 months along 1 year, and cytokines of exhaled breath condensate-EBC [interleukins (IL) 6, 8, 17 and tumoral necrose factor-α (TNF-α)], fractional exhaled NO (FeNO), and disease activity parameters were collected weekly. Specific generalized estimation equation models were used to assess the impact of these pollutants on the risk of Systemic Lupus Erythematous Disease Activity Index 2000 (SLEDAI-2K) ≥ 8, EBC cytokines, and FeNO, considering the fixed effects for repetitive measurements. The models were adjusted for inflammatory indicators, body mass index, infections, medication, and weather variables. An IQR increase in PM2.5 4-day moving average (18.12 µg/m3) was associated with an increase of 0.05 pg/ml (95% CI 0.01; 0.09, p = 0.03) and 0.04 pg/ml (95% CI 0.02; 0.06, p = 0.01) in IL-17 and TNF-α EBC levels, respectively. Additionally, a short-term effect on FeNO was observed: the PM2.5 3-day moving average was associated with a 0.75 ppb increase (95% CI 0.38; 1.29, p = 0.03) in FeNO. Also, an increase of 1.47 (95% CI 1.10; 1.84) in the risk of SLEDAI-2K ≥ 8 was associated with PM2.5 7-day moving average. Exposure to inhalable fine particles increases airway inflammation/pulmonary and then systemic inflammation in cSLE patients.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Contaminación del Aire/efectos adversos , Lupus Eritematoso Sistémico/complicaciones , Neumonía/etiología , Adolescente , Pruebas Respiratorias , Niño , Preescolar , Citocinas/análisis , Femenino , Humanos , Estudios Longitudinales , Lupus Eritematoso Sistémico/diagnóstico , Masculino , Óxido Nítrico/análisis , Neumonía/diagnóstico , Índice de Severidad de la Enfermedad
8.
Environ Health Perspect ; 126(2): 027004, 2018 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-29410382

RESUMEN

BACKGROUND: Long-term air pollution exposure is negatively associated with lung function, yet the mechanisms underlying this association are not fully clear. Differential DNA methylation may explain this association. OBJECTIVES: Our main aim was to study the association between long-term air pollution exposure and DNA methylation. METHODS: We performed a genome-wide methylation study using robust linear regression models in 1,017 subjects from the LifeLines cohort study to analyze the association between exposure to nitrogen dioxide (NO2) and particulate matter (PM2.5, fine particulate matter with aerodynamic diameter ≤2.5 µm; PM10, particulate matter with aerodynamic diameter ≤10 µm) and PM2.5absorbance, indicator of elemental carbon content (estimated with land-use-regression models) with DNA methylation in whole blood (Illumina® HumanMethylation450K BeadChip). Replication of the top hits was attempted in two independent samples from the population-based Cooperative Health Research in the Region of Augsburg studies (KORA). RESULTS: Depending on the p-value threshold used, we found significant associations between NO2 exposure and DNA methylation for seven CpG sites (Bonferroni corrected threshold p<1.19×10-7) or for 4,980 CpG sites (False Discovery Rate<0.05). The top associated CpG site was annotated to the PSMB9 gene (i.e., cg04908668). None of the seven Bonferroni significant CpG-sites were significantly replicated in the two KORA-cohorts. No associations were found for PM exposure. CONCLUSIONS: Long-term NO2 exposure was genome-wide significantly associated with DNA methylation in the identification cohort but not in the replication cohort. Future studies are needed to further elucidate the potential mechanisms underlying NO2-exposure-related respiratory disease. https://doi.org/10.1289/EHP2045.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Metilación de ADN/genética , Exposición a Riesgos Ambientales/efectos adversos , Dióxido de Nitrógeno/toxicidad , Adulto , Contaminantes Atmosféricos/análisis , Contaminación del Aire/efectos adversos , Estudios de Cohortes , Islas de CpG/genética , Exposición a Riesgos Ambientales/análisis , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Dióxido de Nitrógeno/análisis , Material Particulado/análisis , Material Particulado/toxicidad , Pruebas de Función Respiratoria , Factores de Tiempo
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
10.
Fertil Steril ; 99(6): 1681-8, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23419929

RESUMEN

OBJECTIVE: To analyze ovarian and uterine morphologic changes resulting from intrauterine and postnatal exposure to diesel exhaust. DESIGN: Crossover study. Experimental groups: intrauterine and postnatal clean air exposure; intrauterine exposure to diesel only; postnatal exposure to diesel only; and intrauterine and postnatal exposure to diesel. SETTING: Laboratory of Experimental Air Pollution. ANIMAL(S): Swiss mice. INTERVENTION(S): Mice exposed to diesel exhaust with doses that correspond to the daily average PM2.5 levels (fine particles in the ambient air 2.5 µm or less in size) reported by the World Health Organization. MAIN OUTCOME MEASURE(S): Morphometric analyses of the ovaries and uterus were performed to define the relative area occupied by follicles, corpus luteum, and stroma and the proportionate area of glands, epithelial layer, and stroma within the uterine endometrium. RESULT(S): A significant reduction in the proportion of primordial follicles was observed in intrauterine-exposed animals, those exposed during the postnatal period, and in animals exposed during both phases. Primary follicle proportion was reduced in animals exposed during pregnancy. No significant changes were detected in uterine morphology. CONCLUSION(S): Intrauterine exposure to acceptable levels of diesel exhaust compromises the reproductive potential of female mice, diminishing ovarian reserve when sexual maturity is achieved. This effect could increase the risk of premature menopause. The findings raise concern about current environmental guidelines for diesel exposure, warranting more careful examination of this issue in humans by regulatory authorities.


Asunto(s)
Ovario/efectos de los fármacos , Ovario/fisiología , Material Particulado/administración & dosificación , Material Particulado/toxicidad , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Emisiones de Vehículos/toxicidad , Factores de Edad , Animales , Estudios Cruzados , Femenino , Exposición por Inhalación/efectos adversos , Masculino , Ratones , Embarazo , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Reproducción/efectos de los fármacos , Reproducción/fisiología
11.
Toxicol Sci ; 117(1): 200-8, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20525899

RESUMEN

An increased risk of early pregnancy loss in women briefly exposed to high levels of ambient particulate matter during the preconceptional period was recently observed. The effects of this exposure on early embryo development are unknown. This study was designed to assess the dose-response and biological effects of diesel exhaust particles (DEP) on in vitro embryo development using the in vitro fertilization (IVF) mouse model. Zygotes obtained from superovulated mice after IVF were randomly cultured in different DEP concentrations (0, 0.2, 2, and 20 microg/cm(2)) for 5 days and observed for their capacity to attach and develop on a fibronectin matrix until day 8. Main outcome measures included blastocyst rates 96 and 120 h after insemination, hatching discriminatory score, total cell count, proportion of cell allocation to inner cell mass (ICM) and trophectoderm (TE), ICM morphology, attachment rate and outgrowth area, apoptosis and necrosis rates, and Oct-4 and Cdx-2 expression. Multivariate analysis showed a negative dose-dependent effect on early embryo development and hatching process, blastocyst cell allocation, and ICM morphology. Although blastocyst attachment and outgrowth were not affected by DEP, a significant impairment of ICM integrity was observed in day 8 blastocysts. Cell death through apoptosis was significantly higher after DEP exposure. Oct-4 expression and the Oct-4/Cdx-2 ratio were significantly decreased in day 5 blastocysts irrespective of DEP concentration. Results suggest that DEP appear to play an important role in disrupting cell lineage segregation and ICM morphological integrity even at lower concentrations, compromising future growth and viability of the blastocyst.


Asunto(s)
Desarrollo Embrionario/efectos de los fármacos , Emisiones de Vehículos/toxicidad , Animales , Factor de Transcripción CDX2 , Muerte Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Fertilización In Vitro , Perfilación de la Expresión Génica , Proteínas de Homeodominio/genética , Etiquetado Corte-Fin in Situ , Ratones , Factor 3 de Transcripción de Unión a Octámeros/genética , Factores de Transcripción/genética
12.
Fertil Steril ; 90(5): 1921-4, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18222432

RESUMEN

OBJECTIVE: To examine whether there is an association between fetal and/or placental weight and exposure to ambient levels of air pollution in mice. DESIGN: Chronic experiments on mice that were exposed to polluted vs. clean air. SETTING: Environmental exposure to atmospheric pollution. ANIMAL(S): Female Swiss mice (n = 70) were maintained at different stages of gestation in an exposure chamber located at an intersection with heavy traffic in a major city in Brazil. Control mice were maintained in a similar chamber, located adjacent to the exposure chamber but equipped with filters for particles and reactive gases. INTERVENTION(S): Animals were divided into six groups as follows: no exposure, exposure to a polluted chamber throughout gestation, exposure to a polluted chamber during the 1st week of pregnancy, exposure to a polluted chamber during the 2nd and 3rd weeks, exposure to a polluted chamber during the 1st and 2nd week, and exposure to a polluted chamber during the 3rd week. MAIN OUTCOME MEASURE(S): At the end of the gestational period, the determination of fetal and placental weight was performed after cesarean section. RESULT(S): Exposure to air pollution during the 1st week of pregnancy promoted a significant reduction in fetal weight. Mice exposed to polluted air, in any phase of gestation, presented with lower placental weight in comparison to mice maintained in clean chambers. CONCLUSION(S): Exposure to ambient levels of traffic pollution at early phases of gestation is a determinant for decreased final fetal weight. Placental weight is reduced with exposure to air pollution at any phase of gestation.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Peso al Nacer/efectos de los fármacos , Peso Fetal/efectos de los fármacos , Placenta/efectos de los fármacos , Emisiones de Vehículos/toxicidad , Animales , Animales Recién Nacidos , Cámaras de Exposición Atmosférica , Cesárea , Femenino , Edad Gestacional , Exposición Materna , Ratones , Tamaño de los Órganos , Placentación
13.
Fertil Steril ; 87(1): 230-2, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17084397

RESUMEN

A significant negative association (R(2) = 0.7642; P=.013) between particulate matter and secondary sex ratio was found when evaluating people in the city of São Paulo, Brazil. An animal model with male mice raised in nonfiltered open-top chambers showed a significant reduction in the secondary sex ratio (P=.041), suggesting that ambient air pollution may interfere with sex distribution by altering the X:Y sperm proportion in pollution-exposed males.


Asunto(s)
Contaminación del Aire/análisis , Contaminación del Aire/estadística & datos numéricos , Razón de Masculinidad , Animales , Brasil/epidemiología , Ciudades/estadística & datos numéricos , Femenino , Humanos , Masculino , Ratones , Modelos Animales , Estadística como Asunto
14.
São Paulo; s.n; 2006. 117 p. graf, tab, ilus.
Tesis en Portugués | LILACS | ID: lil-609485

RESUMEN

Prévios estudos têm demonstrado alterações nas taxas normais de razão sexual. No entanto, uma associação direta entre níveis ambientais de poluição e razão sexual, não tem sido ainda claramente demonstrada. A fim de investigarmos esta associação, desenvolvemos duas abordagens: uma epidemiológica e outra experimental. O efeito da poluição sobre a população da cidade de São Paulo foi verificado através da associação entre a razão sexual e gradientes de concentração de material particulado (PM10). A fim de conferir plausibilidade biológica aos achados epidemiológicos, camundongos machos com 10 dias de vida, foram expostos em câmaras do tipo Topo Aberto, sob condições de exposição mais controladas. Uma associação negativa e significante foi observada entre razão sexual e PM10, dentro de uma faixa estreita de concentração de PM10 (31 a 61 ?g/m3). Na região menos poluída, a razão sexual foi de 51,7% (106,8) para 34.795 nascimentos registrados, enquanto que para a mais poluída, a proporção decresceu para 50,7% (102,9) para 48.023 nascimentos registrados, com uma redução de 1% no número total de nascimentos masculinos. O grupo de camundongos da linhagem Swiss, acasalados com fêmeas virgens, maduras e não expostas, produziu uma prole com alterações significativas (p<0,041) na razão sexual (0,86) quando comparado com o grupo controle (1,34). Análises morfométricas dos testículos demonstraram alterações significativas no perfil da linhagem germinativa, com reduções no número das espermátides alongadas (p<0,020) e no número total de células (p<0,032). Um decréscimo na concentração dos espermatozóides (46,95x106 /ml) também foi observado nos animais expostos à poluição quando comparado ao grupo controle (54,60x106 /ml). A partir dos nossos resultados podemos concluir que a poluição pode interferir com a distribuição do sexo nas populações expostas aos níveis ambientais de poluição.


Some studies have observed abnormal sex ratios in industrial polluted areas but a direct association between urban levels of air pollutant and sex ratio at birth has not hitherto reported. To examine whether this relationship held true, we evaluated how ambient air pollution interferes on female/male ratio in human and mice models. The effect of air pollution was addressed by determining SSR (secondary sex ratio) across pollution gradients in the city of São Paulo, using inhalable particles (PM10) as a proxy variable for overall pollution levels. To provide biological plausibility to the foregoing epidemiological observation, we designed an experimental study exposing mice in controlled chamber conditions. Results disclosed a significant negative between SSR and PM10, within a relatively narrow range of PM10 levels (31 to 61 ?g/m3). In the least polluted area the sex ratio was 51.7% (106.8) for 34,795 births recorded, and for the most polluted area the proportion decreased to 50.7 % (102.9) for 48,023 births recorded, indicating a difference of 1% in total male births. This result corresponds to a 1,180 unborn male offspring in the highest polluted areas. The group of male Swiss mice housed 10 days after birth in open top chambers exposed to air pollution, where they mate mature and non-exposed virgin female mice, produced an offspring with a 0.86 male/female ratio. The offspring of the group of mice concurrently raised in similar but filtered open top chamber was significantly (p<0.042) higher (1.34). A remarkable result was the testicular histological morphometry with a significant (p<0,020) reduction in the number of elongated spermatids and total cells (p<0,032) of exposed males. In association, a decrease in sperm concentration in the caudal portion of the epidydimus was also found in the exposed mice (46,95x106 /ml) compared to the non-exposed (54,60x106 /ml). In conclusion the findings in our study support the concept that ambient air pollution...


Asunto(s)
Animales , Ratones , Contaminación del Aire , Contaminación Ambiental , Estudios Epidemiológicos , Ratones , Modelos Animales , Razón de Masculinidad
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