Histological and Endocrine Effects of Chronic Exposure to MP2.5 Derived from Wood Smoke in the Uterus of Nulliparous Adult Rats

SUMMARY: The study explores the relationship between chronic exposure to fine particulate matter (PM2.5), sourced from wood smoke, and the histological structure and endocrine function of the uterus in nulliparous adult rats. It assesses potential structural changes in the uterus that could impact reproductive health, viewing PM2.5 exposure as a possible risk factor. A controlled experiment was conducted in a city known for high air pollution levels, exposing rats to filtered and unfiltered air conditions, thus mimicking human PM2.5 exposure. Histological findings indicated a significant increase in collagen density and uterine wall thickness in PM2.5 exposed subjects, suggesting a reproductive function risk. However, no significant differences were observed in progesterone and estradiol hormone levels, pointing to the complex relationship between PM2.5 exposure and its endocrine impact, and emphasizing the need for further studies for a deeper understanding. This work highlights the importance of thoroughly investigating the long-term effects of PM2.5 pollution on reproductive health, underlining the significance of considering environmental exposure as a critical factor in reproductive health research.

El estudio explora la relación entre la exposición crónica a partículas finas (PM2,5), procedentes del humo de leña, y la estructura histológica y la función endocrina del útero en ratas adultas nulíparas. Evalúa posibles cambios estructurales en el útero que podrían afectar la salud reproductiva, considerando la exposición a PM2,5 como un posible factor de riesgo. Se llevó a cabo un experimento controlado en una ciudad conocida por sus altos niveles de contaminación del aire, exponiendo ratas a condiciones de aire filtrado y sin filtrar, imitando así la exposición humana a PM2,5. Los hallazgos histológicos indicaron un aumento significativo en la densidad del colágeno y el grosor de la pared uterina en sujetos expuestos a PM2,5, lo que sugiere un riesgo para la función reproductiva. Sin embargo, no se observaron diferencias significativas en los niveles de las hormonas progesterona y estradiol, lo que apunta a la compleja relación entre la exposición a PM2,5 y su impacto endocrino, y enfatiza la necesidad de realizar más estudios para una comprensión más profunda. Este trabajo destaca la importancia de investigar a fondo los efectos a largo plazo de la contaminación por PM2,5 en la salud reproductiva, subrayando la importancia de considerar la exposición ambiental como un factor crítico en la investigación de la salud reproductiva.

Ambient air pollutants relate to hospital admissions for chronic obstructive pulmonary disease in Ganzhou, China

ABSTRACT OBJECTIVE To evaluate the relationship between ambient air pollutants and chronic obstructive pulmonary disease in relatively low-polluted areas in China. METHODS Atmospheric pollutants levels and meteorological data were obtained from January 2016 to December 2020. The medical database including daily hospital admissions for chronic obstructive pulmonary disease (ICD10: J44) was derived from the First Affiliated Hospital of Gannan Medical University. The generalized additive model was used to analyze the percentage change with 95% confidence interval in daily hospital admissions for chronic obstructive pulmonary disease associated with a 10 µg/m3 increase in atmospheric pollutants levels. RESULTS In total, occurred 4,980 chronic obstructive pulmonary disease hospital admissions (not including emergency department visits) during 2016-2020. The mean concentrations of daily PM2.5, PM10, SO2, NO2, O3, and CO were 37.5 μg/m3, 60.1 μg/m3, 18.7 μg/m3, 23.5 μg/m3, 70.0 μg/m3, and 1.2 mg/m3 in Ganzhou. Each 10 µg/m3 increment of PM2.5, PM10, NO2, and O3 were significantly associated with 2.8% (95%CI: 1.0-4.7), 1.3% (95%CI: 0.3-2.4), 2.8% (95%CI: 0.4-5.4), and 1.5% (95%CI: 0.2-2.7) elevation in daily chronic obstructive pulmonary disease hospital admissions. The estimates of delayed effects of PM2.5, PM10, NO2, and O3 were observed at lag6, lag6, lag8, lag1, respectively. The health effects of particulate pollutants (PM2.5 and PM10) may be independent of other pollutants. The adverse effects of air pollutants were more evident in the warm season (May-Oct) than in the cold season (Nov-Apr). CONCLUSION Our study demonstrated that elevated concentrations of atmospheric pollutant (PM2.5, PM10, NO2, and O3), especially particulate pollutants, can be associated with increased daily count of hospital admissions for chronic obstructive pulmonary disease , which may promote further understanding of the potential hazards of relatively low levels of air pollution on chronic obstructive pulmonary disease and other respiratory disorders.

Advances on the toxicology and molecular mechanisms of different components of ambient fine particulate matter / 中华预防医学杂志

Ambient fine particulate matters (PM2.5) refer to particulate matters with an aerodynamic diameter less than or equal to 2.5 μm. PM2.5 enter the body through the target organ-lung, and can induce a variety of adverse health effects (such as cardiovascular diseases, diabetes, respiratory diseases, neurodegenerative diseases and adverse birth outcomes). PM2.5 are known to have complex compositions (including water-soluble/-insoluble components and biological components), diverse sources and capacity of secondary transformation. Numerous epidemiological and toxicological studies indicated that different components of PM2.5 may induce adverse health effects through different biological mechanisms. In adddition, co-exposure of different components and their interaction should also be considered. Thus here we have systematically reviewed studies in recent years about the toxicological effects and underlying mechanisms of different components of ambient fine particulate matters, including inflammatory response, oxidative stress, endoplasmic reticulum stress, activation of the NF-κB signaling pathway and so on. The information may give some insights into the prevention and treatment of adverse health effects caused by exposure to different components of PM2.5.

Study on DNA methylation in HEB cells exposed to PM(2.5) by application of methylation chip technology / 中华劳动卫生职业病杂志

Objective: To screen the differential methylation sites, genes and pathways of air pollution fine particles (PM(2.5)) on human bronchial epithelial (HBE) cells by methylation chip and bioinformation technology, so as to provide scientific basis for further study of the toxicological mechanism of PM(2.5) on HBE cells. Methods: In August 2020, HBE cells were infected with 10 μg/ml and 50 μg/ml PM(2.5) aqueous solution for 24 h, namely PM(2.5) 10 μg/ml exposure group (low dose group) and PM(2.5) 50 μg/ml exposure group (high dose group) ; uninfected HBE cells were used as control group. The DNA fragments were hybridized with the chip, the chip scanned and read the data, analyzed the data, screened the differential methylation sites, carried out GO analysis and KEGG analysis of the differential methylation sites, and analyzed the interaction relationship of the overall differential methylation sites by functional epigenetic modules (FEMs). Results: Compared with the control group, 127 differential methylation sites were screened in the low-dose group, including 89 genes, including 55 sites with increased methylation level and 72 sites with decreased methylation level. The differential methylation sites were mainly concentrated in the Body region and UTR region. Compared with the control group, 238 differential methylation sites were screened in the high-dose group, including 168 genes, of which 127 sites had increased methylation level and 111 sites had decreased methylation level. The differential heterotopic sites were mainly concentrated in the Body region and UTR region. Through FEMs analysis, 8 genes with the most interaction were screened, of which 6 genes had significant changes in methylation level. MALT1 gene related to apoptosis was found in the heterotopic site of methylation difference in low-dose group; PIK3CA and ARID1A genes related to carcinogenesis were found in the heterotopic sites of methylation difference in high-dose group; TNF genes related to tumor inhibition were found in the results of FEMs analysis. Conclusion: After PM(2.5) exposure to HBE cells, the DNA methylation level is significantly changed, and genes related to apoptosis and carcinogenesis are screened out, suggesting that the carcinogenic mutagenic effect of PM(2.5) may be related to DNA methylation.

Exosomes from PM 2.5-treated Human Bronchial Epithelial Cells Increase Lung Cancer Metastatic Potential / 生物医学与环境科学（英文）

Objective@#Fine particulate matter (PM 2.5) is an air pollutant that has become of great concern in recent years. Numerous studies have found that PM 2.5 may contribute to lung cancer, but the pathogenesis has not yet been fully elucidated. In this study, we explored the roles of exosomes from bronchial epithelial cells in PM 2.5-promoted lung cancer metastasis.@*Methods@#Exosomes were isolated from cell supernatants. An animal model of lung metastasis (established by tail vein injection of A549-luc) and in vitro studies with lung cancer cell lines were used to investigate the effects of exosomes derived from PM 2.5-treated human bronchial epithelial cells (PHBE-exo).@*Results@#The animal experiments revealed that PHBE-exo-treated mice showed stronger luciferase activity and a larger relative metastatic region in the lungs, thus indicating that PHBE-exo promoted the metastatic potential of lung cancer. Additionally, PHBE-exo promoted the migration, invasion and epithelial-to-mesenchymal transition of lung cancer cells, in a manner mediated by activation of c-Jun N-terminal kinase.@*Conclusion@#These results implied that PM 2.5 may promote the development of lung cancer through exosomes derived from bronchial epithelial cells, thus providing a potential interventional target for lung cancer. These findings broadened our understanding of cancer-promoting mechanisms of environmental pollutants.

Effects of early life PM2.5 exposure on prefrontal cortex of offspring male rats / 中国应用生理学杂志

Objective: To investigate the effects of PM2.5 exposure at different stages of early life on the prefrontal cortex of offspring rats. Methods: Twelve pregnant SD rats were randomly divided into four groups: Control group (CG), Maternal pregnancy exposure group (MG), Early postnatal exposure group (EP) and Perinatal period exposure group (PP), 3 rats in each group. The pregnant and offspring rats were exposed to clean air or 8-fold concentrated PM2.5. MG was exposed from gestational day (GD) 1 to GD21. EP was exposed from postnatal day (PND) 1 to PND21, and PP was exposed from GD1 to PND21. After exposure, the prefrontal cortex of 6 offspring rats in each group was analyzed. HE staining was used to observe the pathological damage in the prefrontal cortex. ELISA was employed to detect neuroinflammatory factors, and HPLC/MSC was applied to determine neurotransmitter content. Western blot and colorimetry were applied for detecting astrocyte markers and oxidative stress markers, respectively. Results: Compared with MG and CG, the pathological changes of prefrontal cortex in PP and EP were more obvious. Compared with MG and CG, the neuroinflammatory factors (IL-1, IL-6, TNF-α) in PP and EP were increased significantly (P＜0.01), the level of MT were decreased significantly (P＜0.05), and the level of oxytocin (OT) showed a downward trend; the level of neurotransmitter ACh was also increased significantly (P＜0.01). Compared with MG and CG, the GFAP level of PP and EP showed an upward trend, the level of oxidative stress index SOD in PP and EP was decreased significantly (P＜0.01), and the level of ROS was increased significantly (P＜0.01). Compared with the offspring rats of CG and MG, the CAT level of PP was decreased significantly (P＜0.01, P＜0.05). Compared with the offspring rats of CG, the CAT level of EP was decreased significantly (P＜0.05). There was no significant difference in IL-1, IL-6, TNF-α, MT, OT, ACh, GFAP, SOD, ROS and CAT levels between PP and EP, or MG and CG. Conclusion: PM2.5 exposure in early life has adverse effects on the prefrontal cortex of offspring male rats, and early birth exposure may be more sensitive.

Years of life lost due to premature deaths associated with air pollution: an ecological time-series study

ABSTRACT BACKGROUND: Exposure to air pollutants is associated with hospital admissions due to cardiovascular diseases and premature deaths. OBJECTIVE: To estimate years of life lost (YLL) due to premature deaths and their financial costs. DESIGN AND SETTING: Ecological time-series study carried out in São José dos Campos, Brazil, in 2016. METHODS: Data on deaths among residents of this city in 2016 were assessed to estimate the financial cost of premature deaths associated with air pollution. The diagnoses studied were ischemic heart disease, congestive heart failure and cerebrovascular disease, according to YLL. The fractions attributable to deaths associated with air pollutant exposure and to each potential year of life lost were calculated using negative binomial regression with lags of 0-7 days between exposure and outcome. Nitrogen dioxide, particulate matter (PM10) and ozone concentrations were included in the model and adjusted for temperature, humidity and seasonality. RESULTS: Exposure to particulate matter was significant at lag 3 days. There were 2177 hospitalizations over the study period, with 201 deaths (9.2%). Premature deaths led to 2035.69 years of life lost. A 10 μg/m3 increase in PM10 concentrations was correlated with 8.0% of the hospitalizations, which corresponded to 152.67 YLL (81.67 for males and 71.00 for females). The cost generated was approximately US$ 9.1 million in 2016. CONCLUSION: In this first study conducted in a medium-sized Brazilian city, using the YLL methodology, we identified an excess expense attributable to air pollution.

Aporte de la gestión de episodios críticos a la reducción de enfermedades respiratorias en las ciudades de Los Ángeles y Chillán, Chile / Contribution of the management of critical air pollution episodes to the reduction of respiratory diseases

Background: In southern Chile cities, the emission of air pollutants, especially the use of firewood for heating is restricted during critical air pollution periods. Aim: To analyze how restrictions applied during the management of air pollution critical episodes have contributed to reduce emergency room admissions for respiratory diseases in two Chilean cities between 2013 and 2019. Material and Methods: Poisson regression models were estimated with daily data including explanatory variables, such as the daily and lag concentration of respirable particulate material (PM10), temperature, relative humidity, rainfall, wind speed, seasonal factors, and implementation of different types of critical episodes. Results: The implementation of restrictions during the management of critical pollution episodes decreased emergency room admissions for upper respiratory infections and bronchial obstructive crises, especially when an environmental emergency was decreed during the critical episode. However, the effect on each group of respiratory diseases was heterogeneous between cities, which could be related to avoidance behavior, indoor air pollution, the composition of PM10, or the presence of other pollutants, and not just a reduction in the daily concentration of PM10. Conclusions: The management of critical pollution episodes with restrictions to pollutant emissions is a useful measure to improve population health in cities that have implemented environmental decontamination plans.

Toxic Effects of Long-term Exposure to PM / 中国实验血液学杂志

OBJECTIVE@#To investigate the toxic damage and possible mechanism of chronic exposure of ambient particulate matter (PM@*METHODS@#Mice were treated with different doses (150, 300, 600 mg/kg) of chitosan after exposure to PM@*RESULTS@#Compared with the mice in control group, IL-2 secretion and CXCL12 expression were decreased in the bone marrow of PM@*CONCLUSION@#Chronic exposure of PM

Particulate matter 2.5 triggers airway inflammation and bronchial hyperresponsiveness in mice by activating the SIRT2-p65 pathway / 医学前沿

Exposure to particulate matter 2.5 (PM2.5) potentially triggers airway inflammation by activating nuclear factor-κB (NF-κB). Sirtuin 2 (SIRT2) is a key modulator in inflammation. However, the function and specific mechanisms of SIRT2 in PM2.5-induced airway inflammation are largely understudied. Therefore, this work investigated the mechanisms of SIRT2 in regulating the phosphorylation and acetylation of p65 influenced by PM2.5-induced airway inflammation and bronchial hyperresponsiveness. Results revealed that PM2.5 exposure lowered the expression and activity of SIRT2 in bronchial tissues. Subsequently, SIRT2 impairment promoted the phosphorylation and acetylation of p65 and activated the NF-κB signaling pathway. The activation of p65 triggered airway inflammation, increment of mucus secretion by goblet cells, and acceleration of tracheal stenosis. Meanwhile, p65 phosphorylation and acetylation, airway inflammation, and bronchial hyperresponsiveness were deteriorated in SIRT2 knockout mice exposed to PM2.5. Triptolide (a specific p65 inhibitor) reversed p65 activation and ameliorated PM2.5-induced airway inflammation and bronchial hyperresponsiveness. Our findings provide novel insights into the molecular mechanisms underlying the toxicity of PM2.5 exposure. Triptolide inhibition of p65 phosphorylation and acetylation could be an effective therapeutic approach in averting PM2.5-induced airway inflammation and bronchial hyperresponsiveness.

Human Serum-derived Extracellular Vesicles Protect A549 from PM / 生物医学与环境科学（英文）

Objective@#Epidemiological studies reveal that exposure to fine particulate matter (aerodynamic diameter ≤ 2.5 μm, PM @*Methods@#EVs were isolated from the serum of healthy subjects, quantified @*Results@#PM @*Conclusions@#EVs treatment promotes cell survival and attenuates PM

Impact of maternal exposure to wood smoke pollution on fetal lung morphology in a rat model / Impacto de la exposición materna a la contaminación por humo de leña en la morfología pulmonar fetal en un modelo de rata

SUMMARY: Residential heating with wood is an important source of ambient air pollution. Evidence links air pollution to serious health effects such as respiratory and cardiovascular mortality and morbidity. We hypothesized that prenatal exposure to wood smoke pollution causes morphological changes in the development of the rat lung, leading to altered lung structure and function during later life. We presumed that analysis of the fetal lung stereology provides novel insights into the underlying processes mediating particulate matter associated developmental changes and damage. The objective of the study was to investigate the effects of exposure during gestational period to wood smoke pollution on lung fetal morphology. To test this, pregnant rats were exposed during pregestational and gestational periods to wood smoke pollution. Complete lungs samples were obtained from 24 fetus from healthy female G3 rats subjected to cesarean at 19 days post-fecundation. The lungs were prepared for histological and stereological analysis. The volume fraction of terminal bronchioles VV [tb, lung] and volume fraction of parenchyma VV [par, lung], surface density of terminal bronchioles SV [tb, lung] as well as numerical density of bronchiolar exocrinocytes NA [ec,lung] were calculated by light microscopy. Statistical analysis detected significant differences between groups in volume density VV [tb, lung; %] (p=0.0012) and surface density SV [tb, lung; mm2/mm3] (p<0.0001) of the terminal bronchioles. However, it did not show differences between groups in the stereological parameter volume density VV [par, lung; %] (p=0.0838) and numerical density of bronchiolar exocrinocytes NA [ec,lung; nº/mm2] (p=0.0705). The analysis of the evidence obtained indicates that exposure to environmental pollution was affects lung maturation, and particularly the proportion and area of terminal bronchioles in the fetal lung. In conclusion, maternal exposure to wood smoke pollution during pregnancy was associated with a decrease in the lower conducting airways of lungs, which, according to urban pollution studies, could be related to early childhood lower respiratory illness. The public health implications of this study are that reducing or avoiding exposure to wood smoke is important before and during pregnancy.

RESUMEN: La calefacción residencial con leña es una fuente importante de contaminación ambiental. La evidencia vincula la contaminación del aire con graves efectos sobre la salud, como la mortalidad y la morbilidad respiratoria y cardiovascular. Hipotetizamos que la exposición prenatal a la contaminación por humo de leña causa cambios en el desarrollo del pulmón de rata, lo que conduce a una morfo-función pulmonar alteradas durante la vida posterior, creemos que el análisis de la estereología pulmonar fetal proporcionará nuevos conocimientos sobre los procesos subyacentes que median esos cambios. El objetivo del estudio fue investigar los efectos de la exposición prenatal a la contaminación ambiental por humo de leña sobre la morfología pulmonar fetal. Ratas preñadas fueron expuestas durante los períodos pregestacional y gestacional a la contaminación por humo de leña. En fetos de 19 días post-fecundación fue obtenido el pulmón para análisis histológico y estereológico. Fue determinado la fracción de volumen de bronquiolos terminales VV [tb, pulmón], fracción de volumen del parénquima VV [par, pulmón], densidad superficial de los bronquiolos terminales SV [tb, pulmón] así como la densidad numérica de exocrinocitos NA [ec, pulmón]. El análisis estadístico detectó diferencias significativas entre grupos en la densidad de volumen V [tb, pulmón; %] (p=0,0012) y densidad superficial SV [tb, pulmón; mm2/mm3] (p<0,0001) de los bronquiolos terminales. Sin embargo, no demostró diferencias entre grupos en la densidad de volumen VV [par, pulmón; %] (p=0,0838) y numérica de exocrinocitos bronquiolares NA [ec, pulmón; nº / mm ] (p=0,0705). El análisis de la evidencia obtenida indica que la exposición a la contaminación ambiental afectó la maduración pulmonar, y particularmente la proporción y área de bronquiolos terminales en el pulmón fetal. En conclusión, la exposición materna a la contaminación por humo de leña durante la gestación se asoció a una disminución de las vías respiratorias conductoras de aire en pulmón, lo que, según estudios de contaminación urbana, podría estar relacionado con enfermedades de las vías respiratorias inferiores en la primera infancia. Las implicaciones para la salud pública de este estudio son que reducir o evitar la exposición al humo de leña es importante previo y durante la gestación. Por otro lado, la contaminación por humo de leña tiene un gran impacto en la salud pública que, en teoría, es posible prevenir.

Impacto da queima da cana-de-açúcar sobre internações hospitalares por doenças respiratórias / The impact of sugarcane burning on hospitalization due to respiratory diseases

Resumo O objetivo deste artigo é avaliar o impacto das emissões da queima da cana-de-açúcar sobre o número de internações hospitalares por doenças respiratórias em uma região canavieira. Registros de internações hospitalares por doenças respiratórias foram adquiridas a partir da base de dados referentes ao sistema de informações hospitalares do sistema único de saúde (SIH-SUS), no período de 28 de março de 2011 a 28 de dezembro de 2012. Níveis de MP10, NO2, O3, temperatura e umidade relativa foram registradas. Modelos de regressão logística foram construídos para analisar a associação entre o número total de internações, poluentes atmosféricos e variáveis meteorológicas. Foram registradas 1.179 internações, dentre elas a pneumonia mostrou aumento significativo no período de queima (p = 0,005). Neste mesmo período observou-se que o cluster MP10 e NO2 influenciou 67,9% (IC95%: 11,111-2,537), seguido do cluster MP10, NO2, O3 e temperatura que influenciou 91,1% (IC95%: 1,116; 3,271) no número total de internações. Durante o período de queima houve maior número de internações por doenças respiratórias, principalmente de pneumonia, quando foi observada a influência dos poluentes e temperatura no processo de adoecimento da população.

Abstract The scope of this article is to evaluate the impact of emissions from sugarcane burning on hospital admission numbers for respiratory diseases in a sugarcane region. Hospital admission records for respiratory diseases were acquired from the database of the Hospital Information System of the Unified Health System (SIH-SUS) in the period from March 28, 2011 to December 28, 2012. Levels of PM10, NO2, O3, Temperature and Relative Humidity were recorded. Logistic regression models were created to analyze the association between the total number of hospitalizations, atmospheric pollutants and meteorological variables. A total of 1,179 hospitalization admissions were recorded, with a significant increase in cases of pneumonia in the burning period (p = 0.005). Likewise, it was observed that the cluster of PM10 and NO2 was influenced 67.9% (95% CI: 11.111-2.537) followed by cluster PM10, NO2, O3 and Temperature that influenced 91.1% (95% CI: 1.116; 3.271) in the total number of hospitalization admissions. During the sugarcane burning period there were more hospitalization admissions due to respiratory tract diseases, mainly pneumonia, where the influence of air pollutants and temperature in the process of illness in the population was detected.

Impacto del Material Particulado aéreo (MP 2, 5 ) sobre las hospitalizaciones por enfermedades respiratorias en niños: estudio caso-control alterno / Impact of Particulate Matter (PM 2, 5 ) and children's hospitalizations for respiratory diseases: a case cross-over study

INTRODUCCIÓN: Santiago de Chile con 7 millones de habitantes alcanza elevados niveles de contaminación atmosférica en invierno, el material particulado habitualmente excede los estándares de la OMS. OBJETIVO: Evaluar la influencia de la contaminación atmosférica por material particulado en las hospitalizaciones por enfermedades respiratorias en niños, entre 2001 y 2005 en la Región Metropolitana de Chile, independientemente de la presencia ambiental de virus sincicial respiratorio (VRS). MATERIAL Y MÉTODO: 72.479 hospitalizaciones públicas y privadas por enfermedades respiratorias de niños menores de 15 años residentes en la región del estudio se analizaron con un diseño de caso control alternante, con estratificación temporal. Se evaluó principalmente: hospitalizaciones por enfermedades respiratorias (J00-J99), neumonía (J12-J18); asma (J21.0 - J21.9) y bronquiolitis (J45 - J46). Recopilándose diariamente temperatura, MP10, MP2,5, ozono, virus respiratorios (VRS) y humedad ambientales. RESULTADOS: Los promedios de MP10 y MP2,5 fueron 81,5 y 41,2 pg/m3 respectivamente. El promedio de temperatura fue 12,8 °C y de la humedad del aire 72,6 %. Un aumento de 10 pg/m3 de MP25 con 1 y 2 días de rezago se asoció con un incremento de las hospitalizaciones por enfermedades respiratorias cercano a 2%, este porcentaje aumentó a 5% cuando la exposición fue con 8 días de rezago, reflejando sinergismo entre material particulado y virus respiratorio (VRS). CONCLUSIÓN: La exposición breve a contaminación atmosférica puede provocar hospitalizaciones por enfermedades respiratorias en niños.

INTRODUCTION: With seven million inhabitants, Santiago de Chile reaches high levels of air pollution in winter, the particulate matter usually exceeds WHO standards. OBJECTIVE: To assess the influence of air pollution caused by particulate matter on children's hospitalizations due to respiratory diseases between 2001 and 2005 in the Metropolitan Region of Chile, independently from the environmental presence of respiratory syncytial virus (RSV). MATERIAL AND METHOD: 72,479 public and private hospitalizations due to respiratory diseases of children under 15 years of age residing in the study region were analyzed using a time-stratified alternating case-control design. The main evaluations were: hospitalizations due to respiratory diseases (J00-J99), pneumonia (J12-J18); asthma (J21.0 - J21.9), and bronchiolitis (J45 - J46). Daily compilation of temperature data, PM10, PM2,5, ozone, respiratory virus (RSV), and environmental humidity. RESULTS: Mean values of PM10 and PM2.5 were 81.5 and 41.2 pg/m3 respec tively. The average temperature was 12.8 °C and air humidity 72.6%. An increase of 10 pg/m3 of PM25 with one and two days of lag was associated with an hospitalizations increase due to respiratory diseases close to 2%, this percentage increased to 5% when the exposure was with eight days of lag, reflecting synergism between particulate matter and respiratory viruses (RSV). CONCLUSION: Short air pollution exposure can lead to children's hospitalizations due to respiratory diseases.

Fuzzy logic and hospital admission due to respiratory diseases using estimated values by mathematical model / Lógica fuzzy e internações por doenças respiratórias usando dados estimados por modelo matemático

Abstract Hospitalizations due to respiratory diseases generate financial costs for the Health System in addition to social costs. Objective of this study was to develop and validate a fuzzy linguistic model for prediction of hospitalization due to respiratory diseases. We constructed a fuzzy model for prediction of hospitalizations due to pneumonia, bronchitis, bronchiolitis and asthma second exposure to fine particulate matter (PM2.5) in residents of Volta Redonda, RJ, in 2012. The model contains two inputs, PM2.5 and temperature, with three membership functions for each input, and an output with three membership functions for admissions, which were obtained from DATASUS. There were 752 hospitalizations in the period, the average concentration of PM2.5 was 17.1 µg/m3 (SD = 4.4). The model showed a good accuracy with PM2.5, the result was between 90% and 76.5% for lags 1, 2 and 3, a sensitivity of up to 95%. This study provides support for creating executable software with a low investment, along with the use of a portable instrument could allow number of hospital admission due to respiratory diseases and provide support to local health managers. Furthermore, the fuzzy model is very simple and involves low computational costs, an implementation making possible.

Resumo Internações por doenças respiratórias geram custos financeiros para o Sistema de Saúde além de custos sociais. O objetivo deste estudo foi elaborar e validar um modelo linguístico "fuzzy" para previsão do número de internações por doenças respiratórias. Foi construído um modelo "fuzzy" para predição de internações por pneumonias, bronquite, bronquiolite e asma segundo exposição ao material particulado fino (PM2,5) em residentes de Volta Redonda, RJ, em 2012. O modelo contém duas entradas PM2,5 e temperatura, com três funções de pertinência para cada entrada, e uma saída com três funções de pertinência para internações, que foram obtidas do DATASUS. Foram 752 internações no período, a concentração média do PM2,5 foi 17,1 µg/m3 (dp = 4,4). O modelo mostrou uma boa acurácia com PM2,5, o resultado foi entre 90% e 76,5% para os lags 1, 2 e 3, com sensibilidade de até 95%. Este estudo fornece subsídios para a criação de programa executável, que não exige um grande investimento, juntamente com o uso de um instrumento portátil pode permitir uma estimativa do número de internações e prestar apoio aos gestores municipais de saúde. Além disso, o modelo "fuzzy" é muito simples e implica em baixas despesas computacionais, tornando possível uma implementação.

Antagonistic Effects of N-acetylcysteine on Mitogen-activated Protein Kinase Pathway Activation, Oxidative Stress and Inflammatory Responses in Rats with PM2.5 Induced Lung Injuries / 中国医学科学杂志(英文版)

Objective To evaluate the antagonistic effects of N-acetylcysteine (NAC) on mitogen-activated protein kinases (MAPK) pathway activation, oxidative stress and inflammatory responses in rats with lung injury induced by fine particulate matter (PM2.5). Methods Forty eight male Wistar rats were randomly divided into six groups: blank control group (C1), water drip control group (C2), PM2.5 exposed group (P), low-dose NAC treated and PM2.5 exposed group (L), middle-dose NAC treated and PM2.5 exposed group (M), and high-dose NAC treated and PM2.5 exposed group (H). PM2.5 suspension (7.5 mg/kg) was administered tracheally once a week for four times. NAC of 125 mg/kg, 250 mg/kg and 500 mg/kg was delivered intragastrically to L, M and H group respectively by gavage (10 ml/kg) for six days before PM2.5 exposure. The histopathological changes and human mucin 5 subtype AC (MUC5AC) content in lung tissue of rats were evaluated. We investigated IL-6 in serum and bronchoalveolar lavage fluid (BALF) by Enzyme-linked immunosorbent assay (ELISA), MUC5AC in lung tissue homogenate by ELISA, glutathione peroxidase (GSH-PX) in serum and BALF by spectrophotometry, and the expression of p-ERK1/2, p-JNK1/2 and p-p38 proteins by Western blot. All the measurements were analyzed and compared statistically. Results Lung tissue of rats exposed to PM2.5 showed histological destruction and increased mucus secretion of bronchial epithelial cells. Rats receiving NAC treatment showed less histological destruction and mucus secretion. Of P, L, M and H group, MUC5AC in lung tissue, IL-6 in serum and BALF were higher than controls (C1 and C2) (all P<0.05), with the highest levels found in the P group and a decreasing trend with increase of NAC dose. The activity of GSH-PX in serum and BALF of PM2.5 exposed rats (P, L, M and H) was lower than that of controls (all P<0.05), with higher activities found in NAC treated rats (L, M, and H), and an increasing trend with increase of NAC dose. The expressions of p-ERK1/2, p-JNK1/2 and p-p38 proteins in PM2.5 exposed lung tissue (P, L, M and H) was higher than controls (all P<0.05), with decreased levels and dose dependent downregulation found in NAC treated rats. Conclusion NAC can antagonize major MAPK pathway activation, lung oxidative stress and inflammatory injury induced by PM2.5 in rats.

Coarse particles and hospital admissions due to respiratory diseases in children. An ecological time series study

ABSTRACT BACKGROUND: Exposure to particulate matter (PM) is associated with hospitalizations due to respiratory diseases among children. DESIGN AND SETTING: An ecological time series study was carried out to identify the role of coarse fractions of particulate matter (PM10-2.5) in hospitalizations among children up to 10 years of age, in Piracicaba (SP) in the year 2015. METHODS: A generalized additive model of Poisson regression was used to estimate the risk of hospitalization due to acute laryngitis and tracheitis, pneumonia, bronchitis, bronchiolitis and asthma. Lags of 0 to 7 days were considered, and the model was adjusted for the temperature and relative humidity of the air and controlled for short and long-term exposure. Proportional attributable ratios, population-attributable fractions and hospital costs were calculated with increasing concentrations of these pollutants. RESULTS: 638 hospitalizations were evaluated during this period, with a mean of 1.75 cases per day (standard deviation, SD = 1.86). The daily averages were 22.45 µg/m3 (SD = 13.25) for the coarse fraction (PM10-2.5) and 13.32 µg/m3 (SD = 6.38) for the fine fraction. Significant risks of PM10-2.5 exposure were only observed at lag 0, with relative risk (RR) = 1.012, and at lag 6, with RR = 1.011. An increase of 5 µg/m3 in the coarse fraction concentration implied an increase in the relative risk of hospitalizations of up to 4.8%, with an excess of 72 hospitalizations and excess expenditure of US$ 17,000 per year. CONCLUSIONS: This study showed the impact of coarse-fraction exposure on hospital admissions among children due to respiratory diseases.

A Meta-analysis on the relations between short-term exposure to PM(2.5) and both mortality and related emergency visits in China / 中华流行病学杂志

Objective: To carry out a quantitative estimate that related to the effects of short-term exposure to PM(2.5) on all-cause mortality and emergency visits in China by using the systematic review and Meta-analysis. Methods: We selected all the studies published before March 2018 from China National Knowledge Infrastructure, Wanfang database, PubMed and EMBASE and data on relative risk (RR), excess risk (ER) and their 95%CIs: appeared in these papers were extracted. According to the differences in the size or direction (heterogeneity) of the results, we computed summary estimates of the effect values using a random-effect or fixed effect model. We also conducted the subgroup analysis and Meta-analysis to have assessed the selected studies for the evidence of study bias. Results: A total of 33 original studies, indexed in databases, were identified. Among those studies, 39 sets of data on mortality and 4 sets of data on emergency were valid to show that within the daily concentration range from 47.7 to 176.7 μg/m(3), for 10 μg/m(3) increases in PM(2.5) concentrations, it would increase the daily numbers of deaths by 0.49% (95%CI: 0.39%-0.59%) and 0.30% (95%CI: 0.10%-0.51%) for all-cause deaths and all-cause emergency-room visits, respectively. For subgroup analysis, the combined effect of PM(2.5) in causing short-term all-cause deaths in the northern areas (ER=0.42%, 95%CI: 0.30%-0.54%) seemed lower than that in the southern areas (ER=0.63%, 95%CI: 0.44%-0.82%). The combined effect of PM(2.5) concentration below 75 μg/m(3) (ER=0.50%, 95%CI: 0.37%-0.62%) was higher than that of PM(2.5) concentration ≥75 μg/m(3) (ER=0.39%, 95%CI: 0.26%-0.52%). Conclusion: Within the concentration range from 47.7 to 176.7 μg/m(3), short-term exposure to current level of PM(2.5) might increase both the all-cause daily mortality and daily emergency visits in China.

Efeitos da exposição a poluentes do ar na saúde das crianças de Cuiabá, Mato Grosso, Brasil / Efectos de la exposición a contaminantes del aire en la salud de los niños de Cuiabá, Mato Grosso, Brasil / Effects of exposure to air pollutants on children's health in Cuiabá, Mato Grosso State, Brazil

Exposição a poluentes do ar, que costumam ser quantificados por agências ambientais que não estão presentes em todos os estados, pode estar associada a internações por doenças respiratórias de crianças. Foi desenvolvido um estudo ecológico de séries temporais com dados referentes às internações por algumas doenças respiratórias de crianças menores de dez anos de idade, em 2012, na cidade de Cuiabá, Mato Grosso, Brasil. Os níveis médios de material particulado fino (PM2,5) foram estimados por modelo matemático, os dados de temperatura mínima e umidade relativa do ar foram obtidos do Instituto Nacional de Meteorologia, e número de focos de queimadas do Sistema de Informações Ambientais. A abordagem estatística utilizou o modelo aditivo generalizado da regressão de Poisson com defasagens de 0 a 7 dias. Foram estimados os custos financeiros e aumentos do número de internações decorrentes de elevações de PM2,5. Foram 565 internações (média de 1,54/dia; DP = 1,52) e concentração de PM2,5 de 15,7µg/m3 (DP = 3,2). Foram encontradas associações entre exposição e internações no segundo semestre, nos lags 2 e 3, e quando analisado o ano todo, no lag 2. Uma elevação de 5µg/m3 do PM2,5 implicou o aumento de 89 internações e custos acima dos R$ 95 mil para o Sistema Único de Saúde. Dados estimados por modelo matemático podem ser utilizados em locais onde não há monitoramento de poluentes.

La exposición a contaminantes del aire, que suelen ser cuantificados por agencias ambientales que no están presentes en todos los estados, puede estar asociada a internamientos por enfermedades respiratorias de niños. Se desarrolló un estudio ecológico de series temporales con datos referentes a los internamientos por algunas enfermedades respiratorias de niños menores de 10 años de edad, en 2012, en la ciudad de Cuiabá, Mato Grosso, Brasil. Los niveles medios de material particulado fino (PM2,5) se estimaron mediante un modelo matemático, los datos de temperatura mínima y humedad relativa del aire se obtuvieron del Instituto Nacional de Meteorología, y el número de focos de incendios del Sistema de Información Ambiental. El enfoque estadístico usó el modelo aditivo generalizado de la regresión de Poisson con desfases de 0 a 7 días. Se estimaron los costes financieros y aumentos del número de internamientos derivados de elevaciones de PM2,5. Fueron 565 internamientos (media de 1,54/día; DE = 1,52) y concentración de PM2,5 de 15,7µg/m3 (DE = 3,2). Se encontraron asociaciones entre exposición e internamientos en el segundo semestre, en los lags 2 y 3, y cuando se analizó todo el año, en el lag 2. Una elevación de 5µg/m3 del PM2,5 implicó el aumento de 89 internamientos y costes por encima de los BRL 95 mil para el Sistema Único de Salud. Los datos estimados por el modelo matemático pueden ser utilizados en lugares, donde no existe un monitoreo de contaminantes.

Exposure to air pollutants, usually measured by environmental agencies that are not present in all states, may be associated with respiratory admissions in children. An ecological time series study was conducted with data on hospitalizations due to selected respiratory diseases in children under 10 years of age in 2012 in the city of Cuiabá, Mato Grosso State, Brazil. Mean levels of fine particulate matter (PM2.5) were estimated with a mathematical model, data on low temperatures and relative humidity were obtained from the Brazilian National Institute of Meteorology, and the numbers of brush burnings were obtained from the Environmental Information System. The statistical approach used the Poisson regression generalized additive model with lags of 0 to 7 days. The financial costs and increases in hospitalizations due to increments in PM2.5 were estimated. There were 565 hospitalizations (mean 1.54 admissions/day; SD = 1.52), and mean PM2.5 concentration was 15.7µg/m3 (SD = 3.2). Associations were observed between exposure and hospitalizations in the second semester at lags 2 and 3, and at lag 2 when the entire year was analyzed. An increment of 5µg/m3 in PM2.5 was associated with an increase of 89 hospitalizations and costs exceeding BRL 95,000 (≈ USD 38,000) for the Brazilian Unified National Health System. Data estimated by mathematical models can be used in locations where pollutants are not monitored.

Physical and chemical characteristics of PM2.5 and its toxicity to human bronchial cells BEAS-2B in the winter and summer / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

With the increasing occurrence of haze during the summer, the physicochemical characteristics and toxicity differences in PM2.5 in different seasons are of great concern. Hangzhou is located in an area that has a subtropical monsoon climate where the humidity is very high during both the summer and winter. However, there are limited studies on the seasonal differences in PM2.5 in these weather conditions. In this test, PM2.5 samples were collected in the winter and summer, the morphology and chemical composition of PM2.5 were analyzed, the toxicity of PM2.5 to human bronchial cells BEAS-2B was compared, and the correlation between PM2.5 toxicity and the chemical composition was discussed. The results showed that during both the winter and summer, the main compounds in the PM2.5 samples were water-soluble ions, particularly SO42-, NO3-, and NH4+, followed by organic components, while heavy metals were present at lower levels. The higher the mass concentration of PM2.5, the greater its impact on cell viability and ROS levels. However, when the mass concentration of PM2.5 was similar, the water extraction from the summer samples showed a greater impact on BEAS-2B than that from the winter samples. The cytotoxicity of PM2.5 was closely associated with heavy metals and organic pollutants but less related to water-soluble ions.