The Effect of Atmospheric Pollution on the Thymus

Air pollution is a high-risk factor in megacities’ dwellers because of its effects on health. One of the most important components of the pollution is particulate matter (PM) on which metals are adhered. One element adhered to its surfaces is vanadium (V), and through this route, PM reaches the respiratory system, then the systemic circulation and the rest of the organs. Vanadium is released in the atmosphere as a consequence of the combustion of fossil fuels. Vanadium pentoxide is the compound liberated after the combustion and adhered into PM. Previous studies from our group have reported effects on diverse systems in a mouse model. Besides the morphological changes in the spleen and the decreased function of the immune humoral response, the thymus was also affected. Vanadium inhalation diminished thymic dendritic cells (DCs) and the biomarkers: CD11c and MHCII; in addition, thymic cytoarchitecture changed, demonstrated by cytokeratin-5, and also, modification in the expression of 3-nitrotyrosine was observed. Our findings suggest that autoreactive T cells could be released into the systemic circulation and favor the increase in autoimmune diseases in cities with high concentrations of PM

Sex differences in vanadium inhalation effects in non-ciliated bronchiolar cells

The non-ciliated bronchiolar cell (NCBC) is responsible for the defense of the lung and responds to negative stimuli such as exposure to toxic pro-oxidant substances, which triggers the hyperproduction and hypersecretion of mucins and CC16 protein. The literature demonstrates that physiological and pathological responses in the lung can be influenced by the organism’s sex. The objective of this report was to evaluate response differences to vanadium inhalation in male and female CD-1 mice. Mice were exposed to vanadium for four weeks. Hyperplasia of bronchiolar epithelium, small inflammatory foci and sloughing of the NCBC were observed, without changes between sexes and throughout the exposure time. Mucosecretory metaplasia was found in both males and females, however it was more drastic in males. The expression of CC16 increased in both sexes. This study demonstrated a different susceptibility between male and female mice exposed to vanadium inhalation regarding mucosecretory metaplasia

Oxidative Stress and Vanadium

Air pollution is a worldwide health problem, and metals are one of the various air pollutants to which living creatures are exposed. The pollution by metals such as: lead, cadmium, manganese, and vanadium have a common mechanism of action: the production of oxidative stress in the cell. Oxidative stress favors the production of free radicals, which damage biomolecules such as: DNA, proteins, lipids, and carbohydrates; these free radicals produce changes that are observed in different organs and systems. Vanadium is a transition element delivered into the atmosphere by the combustion of fossil fuels as oxides and adhered to the PM enters into the respiratory system, then crosses the alveolar wall and enters into the systemic circulation. In this chapter, we will review the oxidative stress induced by vanadium—as a common mechanism of metal pollutants—; in addition, we will review the protective effect of the antioxidants (carnosine and ascorbate)

Jak3 Is Involved in Dendritic Cell Maturation and CCR7-Dependent Migration

BACKGROUND: CCR7-mediated signalling is important for dendritic cell maturation and homing to the lymph nodes. We have previously demonstrated that Jak3 participates in the signalling pathway of CCR7 in T lymphocytes. METHODOLOGY AND PRINCIPAL FINDINGS: Here, we used Jak3(-/-) mice to analyze the role of Jak3 in CCR7-mediated dendritic cells migration and function. First, we found no differences in the generation of DCs from Jak3(-/-) bone marrow progenitors, when compared to wild type cells. However, phenotypic analysis of the bone marrow derived DCs obtained from Jak3(-/-) mice showed reduced expression of co-stimulatory molecules compared to wild type (Jak3(+/+)). In addition, when we analyzed the migration of Jak3(-/-) and Jak3(+/+) mature DCs in response to CCL19 and CCL21 chemokines, we found that the absence of Jak3 results in impaired chemotactic responses both in vitro and in vivo. Moreover, lymphocyte proliferation and contact hypersensitivity experiments showed that DC-mediated T lymphocyte activation is reduced in the absence of Jak3. CONCLUSION/SIGNIFICANCE: Altogether, our data provide strong evidence that Jak3 is important for DC maturation, migration and function, through a CCR7-mediated signalling pathway

Visualization and 3D Reconstruction of Flame Cells of Taenia solium (Cestoda)

BACKGROUND: Flame cells are the terminal cells of protonephridial systems, which are part of the excretory systems of invertebrates. Although the knowledge of their biological role is incomplete, there is a consensus that these cells perform excretion/secretion activities. It has been suggested that the flame cells participate in the maintenance of the osmotic environment that the cestodes require to live inside their hosts. In live Platyhelminthes, by light microscopy, the cells appear beating their flames rapidly and, at the ultrastructural, the cells have a large body enclosing a tuft of cilia. Few studies have been performed to define the localization of the cytoskeletal proteins of these cells, and it is unclear how these proteins are involved in cell function. METHODOLOGY/PRINCIPAL FINDINGS: Parasites of two different developmental stages of T. solium were used: cysticerci recovered from naturally infected pigs and intestinal adults obtained from immunosuppressed and experimentally infected golden hamsters. Hamsters were fed viable cysticerci to recover adult parasites after one month of infection. In the present studies focusing on flame cells of cysticerci tissues was performed. Using several methods such as video, confocal and electron microscopy, in addition to computational analysis for reconstruction and modeling, we have provided a 3D visual rendition of the cytoskeletal architecture of Taenia solium flame cells. CONCLUSIONS/SIGNIFICANCE: We consider that visual representations of cells open a new way for understanding the role of these cells in the excretory systems of Platyhelminths. After reconstruction, the observation of high resolution 3D images allowed for virtual observation of the interior composition of cells. A combination of microscopic images, computational reconstructions and 3D modeling of cells appears to be useful for inferring the cellular dynamics of the flame cell cytoskeleton

Ultrastructural glomerular changes in experimental infection with the classical swine fever virus

Ultrastructural studies of glomerular changes were performed on 16 pigs experimentally infected with a highly virulent strain of the classical swine fever virus. Our observations revealed the thickening of glomerular basement membranes, swelling of endothelial cells and cytoplasmic vacuolization within podocytes containing abundant viral particles. An early viral infection of podocytes was suggested as the cause of selective swelling of the foot processes of these cells with the consequent obliteration of the glomerular urinary spaces. To our knowledge this is the first report of ultrastructural evidence of classical swine fever virions infecting glomerular podocytes.Évolution de l'ultrastructure des glomérules rénaux lors d'une infection expérimentale par le virus de la peste porcine classique. Une étude en microscopie électronique des glomérules rénaux a été réalisée afin de mieux appréhender l'évolution de leur ultrastructure lors de l'atteinte rénale associée à la peste porcine classique. Les prélèvements ont été réalisés sur 16 porcelets infectés expérimentalement par une souche très virulente du virus de la fièvre porcine classique. Nos observations ont montré un épaississement de la membrane basale, une tuméfaction des cellules endothéliales associée à la présence de vacuoles dans le cytoplasme des podocytes. De nombreuses particules virales ont été observées dans le cytoplasme des podocytes. Une infection virale précoce des podocytes semble probable, et pourrait expliquer la tuméfaction spécifique de la protubérance podale de ces cellules, et par voie de conséquence, l'obstruction de l'espace urinaire glomérulaire. Actuellement, cette étude est la première à mettre en évidence par ultrastructure des particules virales de la peste porcine classique dans les podocytes glomérulaires

The Effect of Vanadium Inhalation on the Tumor Progression of Urethane-Induced Lung Adenomas in a Mice Model

Lung cancer has the highest death rates. Aerosol drug delivery has been used for other lung diseases. The use of inhaled vanadium (V) as an option for lung cancer treatment is explored. Four groups of mice were studied: (1) Saline inhalation alone, (2) Single intraperitoneal (i.p.) dose of urethane, (3) V nebulization twice a week (Wk) for 8 Wk, and (4) A single dose of urethane and V nebulization for 8 Wk. Mice were sacrificed at the end of the experiment. Number and size of tumors, PCNA (proliferating cell nuclear antigen) and TUNEL (terminal deoxynucleotidyl tranferase dUTP nick-end labeling) immunohistochemistry were evaluated and compared within groups. Results: The size and number of tumors decreased in mice exposed to V-urethane and the TUNEL increased in this group; differences in the PCNA were not observed. Conclusions: Aerosol V delivery increased apoptosis and possibly the growth arrest of the tumors with no respiratory clinical changes in the mice

Identificación de restos de tejidos humanos en instrumentos rituales prehispánicos de México

En este artículo presentamos los resultados del análisis con MEB de cinco instrumentos de sacrificio y dos de autosacrficio de diversas culturas prehispánicas con el fin de encontrar restos orgánicos humanos que los relacionaran con sus funciones. Se trata de cinco elementos elaborados con obsidiana, mientras que los de autosacrificio se componen de una punta de maguey y un punzón tallado en hueso.La obtención de las muestras se logró por medio de la observación de los instrumentos con un microscopio estereoscópico para localizar zonas de interés, luego se tomaron por raspado y desprendimiento de material adherido a la superficie de los diversos instrumentos, así como por la observación directa de minúsculas lascas obtenidas de algunos instrumentos de obsidiana. Posteriormente se montaron en cinta de carbón auto-adherible, se observaron en microscopios electrónicos de barrido Jeol y Zeizz. Se encontraron diversos restos orgánicos como células sanguíneas humanas y restos tisulares

Air Pollution and Retained Particles in the Lung

Epidemiologic evidence associates particulate air pollution with cardiopulmonary morbidity and mortality. The biological mechanisms underlying these associations and the relationship between ambient levels and retained particles in the lung remain uncertain. We examined the parenchymal particle content of 11 autopsy lungs from never-smoking female residents of Mexico City, a region with high ambient particle levels [3-year mean PM₁₀ (particulate matter ≤ 10 μm in aerodynamic diameter)= 66 μg/m³], and 11 control residents of Vancouver, British Columbia, Canada, a region with relatively low levels (3-year mean PM₁₀ = 14 μg/m³). Autopsy lungs were dissolved in bleach and particles were identified and counted by analytical electron microscopy. Total particle concentrations in the Mexico City lungs were significantly higher [geometric mean = 2,055 (geometric SD = 3.9) × 10⁶ particles/g dry lung vs. 279 (1.8) × 10⁶ particles/g dry lung] than in lungs from Vancouver residents. Lungs from Mexico City contained numerous chain aggregated masses of ultrafine carbonaceous spheres, some of which contained sulfur, and aggregates of ultrafine aluminum silicate. These aggregates made up an average of 25% of the total particles by count in the lungs from Mexico City, but were only rarely seen in lungs from Vancouver. These observations indicate for the first time that residence in a region with high levels of ambient particles results in pulmonary retention of large quantities of fine and ultrafine particle aggregates, some of which appear to be combustion products.Medicine, Department ofMedicine, Faculty ofOccupational and Environmental Hygiene, School ofPathology and Laboratory Medicine, Department ofNon UBCReviewedFacult