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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.

Analysis of fuel emissions is crucial for understanding the pathogenesis of mortality because of air pollution. The objective of this study is to assess cardiovascular and inflammatory toxicity of diesel and biodiesel particles. Mice were exposed to fuels for 1 h. Heart rate (HR), heart rate variability, and blood pressure were obtained before exposure, as well as 30 and 60 min after exposure. After 24 h, bronchoalveolar lavage, blood, and bone marrow were collected to evaluate inflammation. B100 decreased the following emission parameters: mass, black carbon, metals, CO, polycyclic aromatic hydrocarbons, and volatile organic compounds compared with B50 and diesel; root mean square of successive differences in the heart beat interval increased with diesel (p < 0.05) compared with control; low frequency increased with diesel (p < 0.01) and B100 (p < 0.05) compared with control; HR increased with B100 (p < 0.05) compared with control; mean corpuscular volume increased with B100 compared with diesel (p < 0.01), B50, and control (p < 0.001); mean corpuscular hemoglobin concentration decreased with B100 compared with B50 (p < 0.001) and control (p < 0.05); leucocytes increased with B50 compared with diesel (p < 0.05); platelets increased with B100 compared with diesel and control (p < 0.05); reticulocytes increased with B50 compared with diesel, control (p < 0.01), and B100 (p < 0.05); metamyelocytes increased with B50 and B100 compared with diesel (p < 0.05); neutrophils increased with diesel and B50 compared with control (p < 0.05); and macrophages increased with diesel (p < 0.01), B50, and B100 (p < 0.05) compared with control. Biodiesel was more toxic than diesel because it promoted cardiovascular alterations as well as pulmonary and systemic inflammation.

In humans, adverse pregnancy outcomes (low birth weight, prematurity, and intrauterine growth retardation) are associated with exposure to urban air pollution. Experimental data have also shown that such exposure elicits adverse reproductive outcomes. We hypothesized that the effects of urban air pollution on pregnancy outcomes could be related to changes in functional morphology of the placenta. To test this, future dams were exposed during pregestational and gestational periods to filtered or nonfiltered air in exposure chambers. Placentas were collected from near-term pregnancies and prepared for microscopical examination. Fields of view on vertical uniform random tissue slices were analyzed using stereological methods. Volumes of placental compartments were estimated, and the labyrinth was analyzed further in terms of its maternal vascular spaces, fetal capillaries, trophoblast, and exchange surface areas. From these primary data, secondary quantities were derived: vessel calibers (expressed as diameters), trophoblast thickness (arithmetic mean), and total and mass-specific morphometric diffusive conductances for oxygen of the intervascular barrier. Two-way analysis of variance showed that both periods of exposure led to significantly smaller fetal weights. Pregestational exposure to nonfiltered air led to significant increases in fetal capillary surface area and in total and mass-specific conductances. However, the calibers of maternal blood spaces were reduced. Gestational exposure to nonfiltered air was associated with reduced volumes, calibers, and surface areas of maternal blood spaces and with greater fetal capillary surfaces and diffusive conductances. The findings indicate that urban air pollution affects placental functional morphology. Fetal weights are compromised despite attempts to improve diffusive transport across the placenta.

The immunoprotective and immunomodulatory role of neutrophils during pulmonary infection of resistant (A/J) and susceptible (B10.A) mice to Paracoccidioides brasiliensis was investigated. First, comparative studies about early cellular influx to the lungs demonstrated higher numbers of neutrophils in susceptible rather than in resistant mice. Neutrophil depletion resulted in decreased survival times of susceptible but not resistant mice. In both mouse strains, depletion led to increased fungal burdens at Week 1 of infection; however, only susceptible mice remained with increased pulmonary fungal loads and presented a dramatic fungal dissemination to liver and spleen. At Week 1 of infection, treated and untreated B10.A and A/J mice were negative for delayed-type hypersensitivity (DTH) reactions, which remained negative for the susceptible strain. In contrast, from the second week onward, control and neutrophil-depleted, resistant mice became positive for DTH reactions. In B10.A mice, neutrophil depletion resulted in increased levels of interleukin (IL)-12 and IL-4 in the lungs, high levels of hepatic cytokines, and increased synthesis of T helper cell type 1 (Th1)- and Th2-regulated antibodies [immunoglobulin G1 (IgG1), IgA, and IgG3]. In neutrophil-depleted A/J mice, high levels of pulmonary IL-12 and granulocyte macrophage-colony stimulating factor were concomitant to diminished levels of hepatic cytokines and increased amounts of Th1-regulated isotypes (IgG2a, IgG2b, and IgG3). Differently from primary infection, neutrophil depletion did not alter immunoprotection in secondary paracoccidioidomycosis. As a whole, our data showed that the genetic patterns of hosts exert an important influence on the immunoprotective and immunoregulatory functions of neutrophils, which appear to be essential in situations devoid of cell-mediated immunity.

The mechanisms involved in the association between air pollution and increased cardiovascular morbidity are not fully understood. The objective of this study was to test the hypothesis that fine particulate matter (PM(2.5)) induces systemic inflammation and vasoconstriction of small arteries in the lung and heart of rats. Thirty-eight healthy Wistar rats were anesthetized, intubated, and submitted to the instillation of 1 ml of distilled water diluted in the following solution: blank filter, 100 microg and 500 microg of PM(2.5). PM(2.5) was collected in glass fiber filters with a high-volume sampler. The animals were sacrificed 24 h after instillation when blood, heart, and lung samples were collected for morphological and wet-to-dry weight ratio analysis. PM(2.5) consisted of the following elements: sulphur, arsenic, bromine, chlorine, cobalt, iron, lanthanum, manganese, antimony, scandium, and thorium. Total reticulocytes significantly increased at both PM(2.5) doses (p < 0.05) while hematocrit levels increased in the 500 microg group (p < 0.05). Quantification of segmented neutrophils and fibrinogen levels showed a significant decrease, while lymphocytes counting increased with 100 microg of PM(2.5) (p < 0.05). A significant dose-dependent decrease of intra-acinar pulmonary arteriole lumen/wall ratio (L/W) was observed in PM groups (p < 0.001). Peribronchiolar arterioles L/W showed a significant decrease in the 500 microg group (p < 0.001). A significant increase in heart wet-to-dry weight ratio was observed in the 500 microg group (p < 0.001). In conclusion, fine environment particles in the city of São Paulo promote pulmonary and cardiac histological alterations. Pulmonary vasculature was markedly affected by particle instillation, resulting in significant vasoconstriction in healthy rats.

Aims: Evaluating the effects of air pollution on Sao Paulo city's vehicular traffic controllers by means of risk indicators for cardiovascular diseases., Methods and Results: Twenty-four hour blood pressure recordings and an electrocardiogram were obtained in 48 healthy, non-smoking vehicular traffic controllers, aged 31-55 years, during three periods: winter 2000, summer 2001, and winter 2001. Effects of air pollutants on the outcomes were estimated using linear regression based on generalized estimated equations, controlling for age, body mass index, humidity, and temperature. An interquartile range (IQR) increase in CO (1.1 p.p.m.) was associated with increases of 2.6 mmHg (95% CI 1.0, 4.2), 1.8 mmHg (95% CI 0.8, 2.8), and 2.4 mmHg (95% CI 1.1, 3.6) in systolic, diastolic, and mean 24 h ambulatory blood pressures. SO(2) also had relevant effects on blood pressure. On heart rate variability, an IQR increase of SO2 (9.6 microg/m3) was negatively associated with the standard deviation (SD) of normal RR intervals (SDNN) -7.93 ms (95% CI -15.3, -0.6)., Conclusion: This study supplies biological plausibility for observational studies on air pollution-related cardiovascular morbidity and mortality.

Secondary lung infiltration by lymphomas occurs frequently. To our knowledge, however, no recent studies have attempted to discriminate histologic patterns of lung infiltration in the lymphoma subtypes. We retrospectively evaluated the frequency of lung infiltration and the respective infiltration patterns by lymphomas at autopsy, during an 11-year period. Lymphomas were classified according to the 2001 World Health Organization Classification of hematologic malignancies in B-cell, T-cell, and Hodgkin lymphomas (HLs). In 21,157 autopsies, 414 reports with lymphoma diagnosis were reviewed histologically, and 85 showed lung infiltration (20.5%). We studied 14 HLs, 43 B-cell lymphomas, and 20 T-cell lymphomas. Five infiltration patterns were identified: peribronchial-perivascular, nodular alveolar, interstitial, and pleural. Approximately half of the lymphomas had more than 1 infiltration pattern (mean, 1.7); peribronchial-perivascular and pleural were the most frequent. The frequency of nodular infiltration was larger in HL than in B-cell lymphomas. T-cell lymphomas had a larger frequency of the interstitial infiltration pattern compared with B-cell lymphomas. Recognizing the frequency and patterns of lung infiltration in the light of a more recent classification is certainly useful for physicians dealing with lymphoma diagnostic procedures, such as radiologists and pathologists.

We report immunohistochemical staining results for cyclooxygenase (COX)-2 and matrix metalloproteinase (MMP)-9 in primary tumors of 117 patients with resected adenocarcinoma of the lung (median follow-up, 20 months). For COX-2, we graded the degree of tumor staining according to the sum of staining intensity and the proportion of cells staining. For MMP-9, we used morphometry to quantify cytoplasmic staining. We used the Cox proportional hazards model to analyze overall survival. With only 29 patients censored at last follow-up, after controlling for the effect of pathologic stage, staining for COX-2 and MMP-9 and subtype of tumor were related significantly to survival (P < 6 x 10(-5)). The effects of COX-2 and MMP-9 were opposite. Whereas any staining for COX-2 decreased the hazard and increased survival time, increased staining for MMP-9 increased the hazard and decreased survival time. The results also suggested that staining for COX-2 decreases with dedifferentiation. Our results suggest that staining for the combination of COX-2 and MMP-9 and categorizing tumors into papillary and nonpapillary types may provide important prognostic information for patients with resected adenocarcinoma of the lung; it is possible that these 3 variables could aid decisions about postoperative adjuvant treatment.

The aim of the present study was to analyse in rats the ability of C-ANCA-positive IgG fraction in triggering inflammatory response on pulmonary tissue. Wistar rats (n = 18) were injected via the the internal jugular vein with 20 mg of total C-ANCA-positive IgG fraction isolated from serum of three different Wegener's granulomatosis patients obtained before therapy. Similarly, control rats were treated with IgG fraction from two rheumatoid arthritis patients (n = 7), IgG from six normal human sera (n = 15) or saline (n = 18), respectively. Animals were sacrificed after 24h of injection for histological analysis of the lungs. Vasculitis and inflammatory infiltrate were consistently absent in rats injected with rheumatoid arthritis IgG or saline and in 14/15 of normal IgG treated animals. In contrast, marked vasculitis was observed in all 18 animals injected with C-ANCA-positive IgG fraction. The histological features were characterized by the presence of a perivascular pleomorphic cellular sheath, particularly around small vessels, endothelial adherence and diapedesis of polymorphonuclear leucocytes and presence of granuloma-like lesions. A dose-response relationship was observed between protein concentration of C-ANCA IgG sample and the intensity of the inflammatory response in the animals. In addition, IgG fraction with undetectable C-ANCA, obtained from one patient in remission after treatment, was not able to reproduce the pulmonary tissue alterations induced by its paired IgG that was positive for C-ANCA taken before therapy. The experimental model described herein may be useful to characterize more effectively the pathogenic mechanism of C-ANCA in Wegener's disease.

Epidemiological studies have reported a positive association of short-term increases in ambient particulate matter (PM) with daily mortality and hospital admissions for cardiovascular disease. Although patients with cardiopulmonary disease appear to be most at risk, particulate-related cardiac effects following myocardial infarction (MI) have not been examined. To improve understanding of mechanisms, we developed and tested a model for investigating the effects of inhaled PM on arrhythmias and heart rate variability (HRV), a measure of autonomic nervous system activity, in rats with acute MI. Left-ventricular MI was induced in 31 Sprague-Dawley rats by thermocoagulation of the left coronary artery; 32 additional rats served as sham-operated controls. Diazepam-sedated rats were exposed (1 h) to residual oil fly ash (ROFA), carbon black, or room air at 12-18 h after surgery. Each exposure was immediately preceded and followed by a 1-h exposure to room air (baseline and recovery periods, respectively). Lead-II electrocardiograms were recorded. In the MI group, 41% of rats exhibited one or more premature ventricular complexes (PVCs) during the baseline period. Exposure to ROFA, but not to carbon black or room air, increased arrhythmia frequency in animals with preexisting PVCs. Furthermore, MI rats exposed to ROFA, but not to carbon black or room air, decreased HRV. There was no difference in arrhythmia frequency or HRV among sham-operated animals. These results underscore the usefulness of this model for elucidating the physiologic mechanisms of pollution-induced cardiovascular arrhythmias and contribute to defining the specific constituents of ambient particles responsible for arrhythmias.

The expression of the nucleolar organizer regions (NORs) was quantified in paraffin sections of tumors and lymph node metastasis, by means of digital image analysis, in 75 patients with resected non-small cell lung cancer (NSCLC). Patients were divided in two groups: early stage (stages I and II) and advanced stage (stages IIIa, IIIb and IV). The prognostic significance of AgNOR expression was tested by Cox regression analysis in models controlled for age, sex, vital status, stage and histological type. Tumors at early stages had a lower expression of AgNOR than those at more advanced diseases. The mean values obtained for NORs in advanced disease were almost the same as those in the primary tumors when compared with the corresponding lymph node metastasis (r = 0.90; p < 0.01; linear regression). The prognostic role of AgNOR was significant only for tumors at stages I and II and not for advanced neoplasms (stages IIIa, IIIb and IV). These results encourage the inclusion of AgNOR quantitation in routine material, especially in early lung cancer.