ABSTRACT
It is known that chicken macrophages derived in vitro from blood monocytes have the capacity to destroy Trypanosoma cruzi, but Toxoplasma gondii can survive within these cells. This study was performed to determine the involvement of nitric oxide (NO) in the killing of T. cruzi by chicken macrophages. Activated (by interferon-gamma and lipopolysaccharide) mouse peritoneal macrophages were used as controls. Macrophages were infected with T. cruzi and T. gondii; after 2, 24, and 48 h, NO was assayed using the Griess reagent. Respiratory-burst involvement, revealed by the reduction of nitroblue tetrazolium (NBT), was determined in chicken macrophages. Chicken macrophages did not produce NO; mouse macrophages were capable of producing NO with no multiplication of parasites. Reduction of NBT could be detected in chicken macrophages that interacted with T. cruzi but was absent in those that interacted with T. gondii. These results demonstrate that chicken macrophages do not use NO as a microbicidal agent when infected with T. cruzi or T. gondii.
Subject(s)
Chickens/parasitology , Macrophages, Peritoneal/parasitology , Nitric Oxide/metabolism , Trypanosoma cruzi/physiology , Animals , Cells, Cultured , Interferon-gamma/pharmacology , Lipopolysaccharides/pharmacology , Macrophage Activation/drug effects , Macrophages, Peritoneal/metabolism , Male , Mice , Nitroblue Tetrazolium/metabolism , Oxidation-Reduction , Toxoplasma/physiologyABSTRACT
Chicken thrombocytes are nucleated cells, analogs to mammalian platelets. These cells are involved in hemostasis, phagocytosis and secretion of specific products. Most of the properties of avian thrombocytes have been established in experiments that employed recently isolated blood cells. Attempts to cultivate these cells for a long period of time under optimal culture conditions for peripheral blood cells were unsuccessful; thrombocytes died after 24 h of cultivation unlike macrophages cocultured with them. Here we investigate the reasons and type of thrombocyte death in culture. Thrombocytes were separated from peripheral blood of roosters and cultured for 48 h. The influence of different culture conditions on thrombocyte viability was studied. Cells were cultured as adherent cell monolayers or under agitation (preventing adherence), in the presence or lack of lymphocytes or their soluble factors, and various concentrations of fetal bovine serum. After 24 h in standard culture thrombocytes displayed cytoplasm and chromatin condensation, DNA cleaved into oligonucleosomal fragments and unaltered mitochondria. These results strongly suggest that thrombocytes suffer an apoptotic cell death in culture. Apoptosis could be delayed by culturing thrombocytes in the presence of lymphocytes or their soluble factors.
Subject(s)
Apoptosis/drug effects , Blood Platelets/drug effects , Culture Media, Conditioned/pharmacology , Animals , Blood Platelets/physiology , Blood Platelets/ultrastructure , Cells, Cultured , Chickens , Culture Media, Conditioned/chemistry , Lymphocytes/metabolism , Male , Microscopy, Electron , Time FactorsABSTRACT
Chicken leukocytes were separated from blood on a Percoll cushion following adherence on coverslips, resulting in a coculture of thrombocytes and monocytes. This system was characterized by light microscopy, scanning and transmission electron microscopy, by lectin binding and actin localization in thrombocytes. During the first 24 hours nuclear condensation, cytoplasmic shrinkage, detachment and death of thrombocytes were observed. In contrast, monocytes gradually increased their spreading capacity, specially after thrombocyte detachment from the coverslips. During culture, a large number of fucose and beta-galactose residues were expressed on the surface of thrombocytes, revealed by the lectins Ulex europaeus I and Arachis hypogaea, respectively. Labeling of the monocyte surface with several lectins also increased with the cultivation time. Thrombocytes showed the formation of a net with actin involvement.
Subject(s)
Blood Platelets/metabolism , Blood Platelets/ultrastructure , Monocytes/metabolism , Monocytes/ultrastructure , Animals , Cell Culture Techniques/methods , Cell Size/physiology , Cells, Cultured , Chickens , Lectins/metabolism , Lectins/pharmacology , Male , Microscopy, Electron, ScanningABSTRACT
Resulting from the the research that has been performed in the Health Center of Campos--RJ, Sanitary Dermatology Service, a total of 854 cases of Hansen's disease were analysed in its principal clinical and epidemiological aspects, in the period from August 1937 until December 1980.
Subject(s)
Leprosy/epidemiology , Adolescent , Adult , Aged , Brazil , Child , Child, Preschool , Female , Humans , Infant , Male , Middle AgedABSTRACT
Resultante de pesquisa realizada no Centro de Saude de Campos - RJ, Servico de Dermatologia Sanitaria, analisa-se um total de 854 casos de hanseniase, no periodo de agosto de 1937 a dezembro de 1980, em seus principais aspectos clinicos e epidemiologicos
Subject(s)
Infant , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Humans , Male , Female , Leprosy , BrazilSubject(s)
Leprosy/immunology , Adolescent , Adult , Aged , Antigens, Bacterial/immunology , Child , Female , Humans , Immunity, Cellular , Intradermal Tests , Male , Middle AgedABSTRACT
A new case of erythema multiforme is described, characterized by multiforme eruption of erythematous papules, plaques and occasional bullous lesions. The acute stage lasts several seeks, then atrophy is noted. The face appears senile. Histopathologically, the lesions show erythema multiforme in the acute phase; in the atrophic stage, a disappearance of the elastic fibers was observed.
