ABSTRACT
The invasive golden mussel, Limnoperna fortunei (Dunker, 1857), was introduced into the La Plata River estuary and quickly expanded upstream to the North, into the Paraguay and Paraná rivers. An ecological niche modeling approach, based on limnological variables, was used to predict the expansion of the golden mussel in the Paraguay River and its tributaries. We used three approaches to predict the geographic distribution: 1) the spatial distribution of calcium concentration and the saturation index for calcium carbonate (calcite); 2) the Genetic Algorithm for Rule-Set Production (GARP) model; and the 3) Maximum Entropy Method (Maxent) model. Other limnological variables such as temperature, dissolved oxygen, pH, and Total Suspended Solids (TSS) were used in the latter two cases. Important tributaries of the Paraguay River such as the Cuiabá and Miranda/Aquidauana rivers exhibit high risk of invasion, while lower risk was observed in the chemically dilute waters of the middle basin where shell calcification may be limited by low calcium concentrations and carbonate mineral undersaturation.
Subject(s)
Calcium Carbonate/analysis , Environmental Monitoring/methods , Introduced Species , Mytilidae/physiology , Rivers/chemistry , Algorithms , Animals , Brazil , Mytilidae/classification , Population DynamicsABSTRACT
In five lung biopsies from patients who developed the clinical picture of Adult Respiratory Distress Syndrome (ARDS) after cardiopulmonary bypass the pulmonary alterations were studied morphologically and glucocorticoid receptors determined. The time between cardiac surgery and pulmonary biopsy was 4-7 days. The results showed severe pulmonary lesions, with marked endothelial damage and active collagen secretion in the pulmonary interstitium, along the capillary bed. The glucocorticoid receptor level of the lungs with ARDS was 4.7 +/- 7.04 fmol/mg protein (control 4.28 +/- 4.32 fmol/mg protein). The results indicate that the process of collagen secretion may begin in the early phase of ARDS and that the benefits of glucocorticoid therapy in the management of ARDS should be reassessed.
Subject(s)
Lung/pathology , Pulmonary Fibrosis/pathology , Receptors, Glucocorticoid/analysis , Respiratory Distress Syndrome/pathology , Cardiopulmonary Bypass , Humans , Male , Middle Aged , Postoperative Complications , Pulmonary Fibrosis/etiology , Respiratory Distress Syndrome/etiologyABSTRACT
A comparative chronic inhalation exposure study was performed to investigate the potential health effects of gasoline and ethanol engine exhaust fumes. Test atmospheres of gasoline and ethanol exhaust were given to Wistar rats and Balb C mice housed in inhalation chambers for a period of 5 weeks. Gas concentration and physical parameters were continually monitored during the exposure period. Several biological parameters were assessed after the exposure including pulmonary function, mutagenicity, and hematological, biochemical, and morphological examinations. The results demonstrated that the chronic toxicity of the gasoline-fueled engine is significantly higher than that of the ethanol engine.
Subject(s)
Ethanol/toxicity , Gasoline/toxicity , Lung/drug effects , Petroleum/toxicity , Vehicle Emissions/toxicity , Animals , Atmosphere Exposure Chambers , Blood/drug effects , Body Weight/drug effects , Lung/pathology , Male , Mice , Mice, Inbred BALB C , Mutagenicity Tests , Rats , Rats, Inbred Strains , Species SpecificityABSTRACT
Two groups of 12 male Wistar rats received either 243 ppm of acetaldehyde or 5.7 ppm of formaldehyde for 8 h a day, 5 days a week during 5 weeks. These levels represent three times the threshold limit values (TLV) for these substances in Brazilian legislation. The animals were evaluated by pulmonary function tests before and after exposure to the pollutants. The data obtained from these rats were compared with those of 12 controls, housed in identical conditions for the same length of time but breathing normal air. The results showed an increase of the functional residual capacity, residual volume, total lung capacity and respiratory frequency in the rats exposed to acetaldehyde atmosphere. The animals exposed to formaldehyde did not present pulmonary function alterations when compared with the controls. The damage caused by acetaldehyde to the peripheral regions of the lung parenchyma, affecting small airways or altering pulmonary elastic properties, is discussed. It is suggested that the Brazilian TLV for acetaldehyde (78 ppm) is not as safe as that for formaldehyde (1.6 ppm).
Subject(s)
Acetaldehyde/toxicity , Air Pollutants/toxicity , Formaldehyde/toxicity , Lung/drug effects , Animals , Male , Maximum Allowable Concentration , Rats , Rats, Inbred Strains , Respiratory Function TestsABSTRACT
The level of cytosolic glucocorticoid receptors (GR) was measured in 12 open-chest lung biopsies of interstitial pulmonary diseases. The results showed an increase in the GR content in the diseased lungs correlated to the degree of septal cellularity in nine cases. Two pulmonary sarcoidosis and one end-stage idiopathic pulmonary fibrosis patients presented higher levels of GR than those predicted by the septal cellularity. It was concluded that the GR content of the lungs increases in the course of interstitial diseases, reflecting the number of cells that express cytosolic GR in pulmonary parenchyma.
Subject(s)
Lung/metabolism , Pulmonary Fibrosis/metabolism , Receptors, Glucocorticoid/metabolism , Receptors, Steroid/metabolism , Adult , Aged , Female , Humans , Lung/pathology , Lung Diseases/metabolism , Male , Middle Aged , Pneumonia/metabolism , Pulmonary Fibrosis/pathology , Regression Analysis , Respiratory Distress Syndrome/metabolism , Sarcoidosis/metabolismABSTRACT
This paper describes the effects of repeated exposure to gasoline and ethanol exhaust fumes on the pulmonary mechanics of rats assessed by whole-body plethysmography. Two groups of 12 male Wistar albino rats each were tested before and after exposure to diluted gasoline or ethanol exhaust gases for 5 weeks, 8 h per day and 5 days per week. An additional group of 12 rats were exposed to clean air under the same experimental conditions. The variations of the functional parameters observed in the three groups before and after exposure were compared. Peak Expiratory Flow and Forced Expiratory Mean Flows in the ranges 0-25%, 25-50% and 50-75% of Forced Vital Capacity were significantly reduced in animals exposed to gasoline exhaust fumes, whereas the group exposed to ethanol exhaust fumes did not differ from the control group. This respiratory impairment is probably due to the presence of SO2 and the quality of the hydrocarbons in gasoline exhaust gases.
Subject(s)
Ethanol/toxicity , Gasoline/toxicity , Lung/drug effects , Petroleum/toxicity , Vehicle Emissions/toxicity , Animals , Lung/physiopathology , Male , Rats , Rats, Inbred Strains , Respiratory Function TestsABSTRACT
A simple technic for studying the pulmonary mechanics of rats by whole body plethysmography is presented. The parameters measured were: Tidal Volume (TV); Respiratory Frequency (RF); Transpulmonary Basal Pressure (TBP); Dynamic Compliance (Cdyn); Functional Residual Capacity (FRC); Transpulmonary Pressure/Volume curve (TP/V); Forced Expiratory Volume of 1/4 second (FEV 1/4); Expiratory Reserve Volume (ERV); Inspiratory Capacity (IC); Inspiratory Reserve Volume (IRV); Forced Vital Capacity (FVC); Residual Volume (RV); Forced Expiratory Mean Flow between 100-50% (FEMF 100-50), 50-25% (FEMF 50-25) and 25-0% (FEMF 25-0) of the FVC, and Total Lung Capacity (TLC). In order to verify the accuracy of the technic, common male adult Wistar rats, in which pulmonary obstructive disease is normally expected, were first submitted to these functional tests and then to pathological examination. According to the intensity of the morphological pulmonary lesion, the rats were divided in two groups: with and without suppurative pneumopathy. The analysis of the pulmonary function data showed significant decrease of the FEV 1/4 and FEMF 50-25 and increase of the FRC and RV in the groups with pulmonary suppuration. Thus, a discriminant function could be established to characterize the two groups with 100% efficiency. It was concluded that these pulmonary function tests are a valuable and reliable tool to detect lung diseases in rats.
Subject(s)
Lung/physiology , Plethysmography, Whole Body , Animals , Biomechanical Phenomena , Lung/physiopathology , Lung Diseases, Obstructive/physiopathology , Lung Volume Measurements , Male , Rats , Rats, Inbred Strains , Respiratory Function TestsABSTRACT
A simple technic for studying the pulmonary mechanics of rats by whole body plethysmography is presented. The parameters measured were: Tidal Volume (TV); Respiratory Frequency (RF); Transpulmonary Basal Pressure (TBP); Dynamic Compliance (Cdyn); Functional Residual Capacity (FRC); Transpulmonary Pressure/Volume curve (TP/V); Forced Expiratory Volume of 1/4 second (FEV 1/4); Expiratory Reserve Volume (ERV); Inspiratory Capacity (IC); Inspiratory Reserve Volume (IRV); Forced Vital Capacity (FVC); Residual Volume (RV); Forced Expiratory Mean Flow between 100-50
(FEMF 100-50), 50-25
(FEMF 50-25) and 25-0
(FEMF 25-0) of the FVC, and Total Lung Capacity (TLC). In order to verify the accuracy of the technic, common male adult Wistar rats, in which pulmonary obstructive disease is normally expected, were first submitted to these functional tests and then to pathological examination. According to the intensity of the morphological pulmonary lesion, the rats were divided in two groups: with and without suppurative pneumopathy. The analysis of the pulmonary function data showed significant decrease of the FEV 1/4 and FEMF 50-25 and increase of the FRC and RV in the groups with pulmonary suppuration. Thus, a discriminant function could be established to characterize the two groups with 100
efficiency. It was concluded that these pulmonary function tests are a valuable and reliable tool to detect lung diseases in rats.
