Mariângela Macchione

The effects of chronic exposure to traffic derived air pollution on the ocular surface.

OBJECTIVES The purpose of this study was to explore the clinical relevance of chronic exposure to ambient levels of traffic derived air pollution on the ocular surface. METHODS A panel study involving 55 volunteers was carried out in São Paulo, Brazil. We measured the mean individual levels of nitrogen dioxide (NO(2)) exposure for 7 days. All subjects answered the Ocular Symptom Disease Index (OSDI) and a symptoms inventory. Subsequently, subjects underwent Schirmer I test, biomicroscopy, vital staining and tear breakup time (TBUT) assessment. Subjects mean daily exposure to NO(2) was categorized in quartiles. Statistical analysis was performed using one-way ANOVA, Tukey HSD and Chi-Square tests. RESULTS A dose-response pattern was detected between OSDI scores and NO(2) quartiles (p<0.05). There was a significant association between NO(2) quartiles and reported ocular irritation (Chi(2)=9.2, p<0.05) and a significant negative association between TBUT and NO(2) exposure (p<0.05, R=-0.316, Spearmans correlation). There was a significant increase in the frequency of meibomitis in subjects exposed to higher levels of NO(2) (p<0.05). CONCLUSIONS Subjects exposed to higher levels of traffic derived air pollution reported more ocular discomfort symptoms and presented greater tear film instability, suggesting that the ocular discomfort symptoms and tear breakup time could be used as convenient bioindicators of the adverse health effects of traffic derived air pollution exposure.

Subchronic effects of nasally instilled diesel exhaust particulates on the nasal and airway epithelia in mice

Diesel exhaust is the major source of ultrafine particles released during traffic-related pollution. Subjects with chronic respiratory diseases are at greater risk for exacerbations during exposure to air pollution. This study evaluated the effects of subchronic exposure to a low-dose of diesel exhaust particles (DEP). Sixty male BALB/c mice were divided into two groups: (a) Saline: nasal instillation of saline (n = 30); and (b) DEP: nasal instillation of 30 µg of DEP/10 µl of saline (n = 30). Nasal instillations were performed 5 days a week, over 30 and 60 days. Animals were anesthetized with pentobarbital sodium (50 mg/kg intraperitoneal [i.p.]) and sacrificed by exsanguination. Bronchoalveolar lavage (BAL) fluid was performed to evaluate the inflammatory cell count and the concentrations of the interleukin (IL)-4, IL-10, and IL-13 by enzyme-linked immunosorbent assay (ELISA). The gene expression of oligomeric mucus/gel-forming (Muc5ac) was evaluated by real-time polymerase chain reaction (PCR). Histological analysis in the nasal septum and bronchioles was used to evaluate the bronchial and nasal epithelium thickness as well as the acidic and neutral nasal mucus content. The saline group (30 and 60 days) did not show any changes in any of the parameters. However, the instillation of DEP over 60 days increased the expression of Muc5ac in the lungs and the acid mucus content in the nose compared with the 30-day treatment, and it increased the total leukocytes in the BAL and the nasal epithelium thickness compared with saline for 60 days. Cytokines concentrations in the BAL were detectable, with no differences among the groups. Our data suggest that a low-dose of DEP over 60 days induces respiratory tract inflammation.

Effects of formaldehyde on the frog's mucociliary epithelium as a surrogate to evaluate air pollution effects on the respiratory epithelium

The increasing use of alcohol as an alternative fuel to gasoline or diesel can increase emission of formaldehyde, an organic gas that is irritant to the mucous membranes. The respiratory system is the major target of air pollutants and its major defense mechanism depends on the continuous activity of the cilia and the resulting constant transportation of mucous secretion. The present study was designed to evaluate the effects of formaldehyde on the ciliated epithelium through a relative large dose range around the threshold limit value adopted by the Brazilian legislation, namely 1.6 ppm (1.25 to 5 ppm). For this purpose, the isolated frog palate preparation was used as the target of toxic injury. Four groups of frog palates were exposed to diluted Ringer solution (control, N = 8) and formaldehyde diluted in Ringer solution at three different concentrations (1.25, 2.5 and 5.0 ppm, N = 10 for each group). Mucociliary clearance and ciliary beat frequency decreased significantly in contact with formaldehyde at the concentrations of 2.5 and 5.0 ppm after 60 min of exposure (P<0.05). We conclude that relatively low concentrations of formaldehyde, which is even below the Brazilian threshold limit value, are sufficient to cause short-term mucociliary impairment.

Methods for studying mucociliary transport

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.

Métodos de estudo do transporte mucociliar

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

Acute cardiopulmonary effects induced by the inhalation of concentrated ambient particles during seasonal variation in the city of São Paulo.

Ambient particles may undergo modifications to their chemical composition as a consequence of climatic variability. The determination of whether these changes modify the toxicity of the particles is important for the understanding of the health effects associated with particle exposure. The objectives were to determine whether low levels of particles promote cardiopulmonary effects, and to assess if the observed alterations are influenced by season. Mice were exposed to 200 μg/m(3) concentrated ambient particles (CAPs) and filtered air (FA) in cold/dry and warm/humid periods. Lung hyperresponsiveness, heart rate, heart rate variability, and blood pressure were evaluated 30 min after each exposure. After 24 h, blood and tissue samples were collected. During both periods (warm/humid and cold/dry), CAPs induced alterations in red blood cells and lung inflammation. During the cold/dry period, CAPs reduced the mean corpuscular volume levels and increased erythrocytes, hemoglobin, mean corpuscular hemoglobin concentration, and red cell distribution width coefficient variation levels compared with the FA group. Similarly, CAPs during the warm/humid period decreased mean corpuscular volume levels and increased erythrocytes, hemoglobin, hematocrit, and red cell distribution width coefficient variation levels compared with the FA group. CAPs during the cold/dry period increased the influx of neutrophils in the alveolar parenchyma. Short-term exposure to low concentrations of CAPs elicited modest but significant pulmonary inflammation and, to a lesser extent, changes in blood parameters. In addition, our data support the concept that changes in climate conditions slightly modify particle toxicity because equivalent doses of CAPs in the cold/dry period produced a more exacerbated response.

Salbutamol improves markers of epithelial function in mice with chronic allergic pulmonary inflammation

We investigated the effects of salbutamol on the markers of epithelial function in a murine model of chronic allergic pulmonary inflammation by recording the ciliary beat frequency (CBF) and the transepithelial potential difference (PD) in vivo. Mice were sensitized and received four challenges of ovalbumin (OVA group) or 0.9% saline (control group). Forty-eight hours after the 4th inhalation, we observed eosinophilia in the bronchoalveolar lavage and epithelium remodeling with stored acid mucus in the OVA group (P < 0.001). No difference in the baseline CBF was noticed between the groups; however, the OVA group had a significantly lower baseline PD (P = 0.013). Salbutamol increased the CBF in all groups studied, and the dose response curve to salbutamol increased the PD in the OVA group from 10(-4)M to 10(-2)M. We suggest that salbutamol affects the CBF and the depth of the periciliary layer, which, in great part, determines the ability of the cilia to propel the mucus layer. This effect may have a positive impact on airway mucociliary transport in asthma and may have clinical implications.

Organic and Inorganic Fractions of Diesel Exhaust Particles Produce Changes in Mucin Profile of Mouse Trachea Explants

Diesel exhaust particles (DEP) contain organic and inorganic elements that produce damage to the respiratory epithelium. The aim of this study was to determine the mucus profile of tracheal explants exposed to either crude diesel exhaust particles (DEP) or DEP treated with nitric acid (DEP/NA), with hexane (DEP/HEX), or with methanol (DEP/MET) at concentrations of 50 and 100 μg/ml for 30 and 60 min. Tracheal explants were subjected to morphometric analyses to study acidic (AB+), neutral (PAS+), and mixed (AB+/PAS+) mucus production and vacuolization (V). Incubation with 50 μg/ml crude DEP resulted in a rise in acid mucus production, an increase in vacuolization at 30 min, and reduction in neutral mucus at 30 and 60 min. Tracheas exposed to DEP/MET at 50 μg/ml for 30 or 60 min resulted in a significant decrease in neutral mucus production and an elevation in acid mucus production. DEP/HEX increased vacuolization at both 50 and 100 μg/ml at 30 and 60 min of exposure. Treatment with 50 μg/ml for 30 or 60 min significantly elevated mixed mucus levels. These results suggest that DEP appear to be more toxic when administered in combination with HEX or MET. DEP/MET modified the mucus profile of the epithelium, while DEP/HEX altered mucus extrusion, and these responses might be due to bioavailability of individual elements in DEP fractions.

Avaliação da qualidade de vida relacionada à saúde de cortadores de cana-de-açúcar nos períodos de entressafra e safra

OBJETIVO: Avaliar a qualidade de vida relacionada a saude de cortadores de cana-de-acucar. METODOS: Estudo longitudinal em uma usina sucroalcooleira no Oeste do estado de Sao Paulo de abril (final da entressafra) a outubro (final da safra) de 2010. Foram avaliados 44 cortadores de cana-de-acucar tabagistas e nao tabagistas em tres periodos: ao final da entressafra, no fim do terceiro mes de safra e no final da safra. A qualidade de vida relacionada a saude foi avaliada pelo questionario Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). Foram realizados analise de variância para medidas repetidas e teste de Friedman para comparar a qualidade de vida entre os periodos. Utilizou-se o teste de Goodman para identificar a frequencia dos trabalhadores cujo escore aumentou nos periodos de safra em comparacao com a entressafra (respondedores positivos), considerando-se as variaveis qualitativas dos dominios do SF-36. RESULTADOS: Ao final da entressafra, 23% dos trabalhadores desistiram do trabalho; 27% eram tabagistas. Houve decrescimo significativo no dominio vitalidade no final da safra em comparacao com a entressafra. Os desistentes apresentaram maior escore no dominio aspecto social em relacao ao grupo que permaneceu no trabalho. Nao houve diferenca na qualidade de vida relacionada a saude entre tabagistas e nao tabagistas. No entanto, observou-se maior percentual de respondedores positivos entre nao tabagistas nos dominios aspecto fisico, social e emocional nos tres meses de safra e nos dominios estado geral de saude e aspecto social nos seis meses de safra, quando comparados aos tabagistas. CONCLUSOES: A qualidade de vida relacionada a saude em cortadores de cana-de-acucar mostrou-se diminuida apos o periodo de safra no dominio vitalidade. Os trabalhadores que permaneceram na safra sao os que apresentaram piores aspectos sociais, o que mostra a necessidade de promocao de politicas assistencialistas de saude a essa populacao especifica, principalmente durante a safra canavieira.OBJECTIVE To assess health-related quality of life in sugarcane cutters. METHODS Longitudinal study conducted in a sugar and ethanol plant located in the western region of the State of São Paulo (Southeastern Brazil) from April (pre-harvest) to October (harvest) 2010. A total of 44 sugarcane cutters, smokers and non-smokers, was evaluated in three periods: pre-harvest, at the end of the third month during harvest and at the end of harvest. Health-related quality of life was assessed by the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). Analysis of variance for repeated measures and the Friedman test were performed to compare quality of life among the periods. To identify the frequency of workers whose score increased in the harvest periods compared to pre-harvest (positive responders), the Goodman test was used, considering the qualitative variables of the SF-36 domains. RESULTS At the end of pre-harvest, 23% workers drop out of work; 27% were smokers. There was a significant decrease in the vitality domain at the end of harvest compared to pre-harvest. The dropouts presented higher score in the social aspect domain compared to the group that remained working. There was no difference in health-related quality of life between smokers and non-smokers. However, there was a higher percentage of positive responders among non-smokers in the physical, social and emotional domains in the third month of harvest and in the general health status and social domains at the end of harvest, compared to smokers. CONCLUSIONS Health-related quality of life in sugarcane cutters was reduced after the harvest period in the vitality domain. The individuals who remained working during harvest are those with lower scores for social aspects, which demonstrates the need to promote health assistance policies for this specific population, particularly during sugar harvest.

Effects of organic and inorganic compounds of diesel exhaust particles on the mucociliary epithelium: An experimental study on the frog palate preparation

The toxic actions of acute exposition to different diesel exhaust particles (DEPA) fractions on the mucociliary epithelium are not yet fully understood due to different concentrations of organic and inorganic elements. These chemicals elements produce damage to the respiratory epithelium and exacerbate pre-existent diseases. In our study we showed these differences in two experimental studies. Study I (dose-response curve - DRCS): Forty frog-palates were exposed to the following dilutions: frog ringer, intact DEPA diluted in frog-ringer at 3mg/L, 6mg/L and 12mg/L. Study II (DEPF) (DEPA fractions diluted at 12mg/L): Fifty palates - Frog ringer, intact DEPA, DEPA treated with hexane, nitric acid and methanol. Variables analyzed: relative time of mucociliary transport (MCT), ciliary beating frequency (CBF) and morphometric analysis for mucin profile (neutral/acid) and vacuolization. The Results of DRCS: Group DEPA-12mg/L presented a significant increase in the MCT (p<0.05), proportional volume of acid mucus (p<0.05) and decreased proportional volume of neutral mucus and vacuoles (p<0.05). In relation of DEPF: A significant increase in the MCT associated to a decrease in the proportional volume of neutral mucus was founded in nitric acid group. In addition, a significant increase in the proportional volume of acid mucus was found in methanol group. We concluded that: 1) Increasing concentrations of intact DEPA can progressively increase MCT and promote an acidification of intra-epithelial mucins associated to a depletion of neutral mucus. 2) Intact DEPA seem to act as secretagogue substance, promoting mucus extrusion and consequently reducing epithelial thickness. 3) Organic fraction of low polarity seems to play a pivotal role on the acute toxicity to the mucociliary epithelium, by promoting a significant increase in the MCT associated to changes in the chemical profile of the intracellular mucins.