Guedes J.R.P.,University of Sao Paulo |
Carrasco S.,University of Sao Paulo |
Ferreira C.M.,Fishery Institute |
Bonamin L.V.,Paulista University |
And 5 more authors.
Homeopathy | Year: 2011
Background: Ultra High Dilutions (UHD) are diluted beyond the Avogadro limit with dynamization (dilution with succussion). The process of anuran amphibian metamorphosis is controlled by thyroid hormones, including the resorption of the tadpole tail. Methods: A randomized and blinded study was performed to investigate the influence of triiodothyronine (T3) 5·10 -24M (10cH) on apoptosis induced by T3 100nM in Rana catesbeiana tadpoles' tail tips, in vitro. Explants were randomized to three groups: control: no T3 in pharmacological or UHD dose; test: T3 100nM and challenged with T3 10cH (UHD); positive control: T3 100nM, treated with unsuccussed ethanol. The apoptotic index and the area of explants of test and control groups at the first and final day of the experiment were compared by t-test. Results: There was no difference in tail tip area between test and control groups, but a significantly higher (p<0.01) index of apoptosis in explants of the test group. Conclusion: This data suggest that T3 10cH modifies the effect of T3 at pharmacological dose, opening new perspectives for further studies and investigation of the dose-effect curve. © 2011 The Faculty of Homeopathy. Source
Santos A.A.,University of Sao Paulo |
Gutierre R.C.,University of Sao Paulo |
Antoniazzi M.M.,Instituto Butantan |
Ranzani-Paiva M.J.T.,Fishery Institute |
And 3 more authors.
Journal of Fish Biology | Year: 2011
This study characterized the structure and the morphocytochemical, immunohistochemical and ultrastructural aspects of the head kidney (HK) of the fat snook Centropomus parallelus. The HK is enclosed by a thin capsule of connective tissue, from which fine trabeculae originate and branch into the interior of organ. In the parenchyma, there are aggregates of lymphoid cells containing populations of lymphocytes T immunopositive for CDRO45, in a nodular arrangement, around blood vessels and melano-macrophage centres. Among the cells that constituted these aggregates and surrounded them, were macrophages and monocytes, and their precursors, with strong immunopositivity for CD68, along with cells of the granulocytic lineage in various phases of maturation positive for lysozyme and PAS. Macrophages and chromaffin and interrenal cells are also present. Ultrastructurally, the HK comprises a reticulum-endothelial stroma consisting of endothelial cells, reticulocytes of the fibroblast type and macrophage type and a parenchyma with increased cellularity, principally blood cells of the erythrocytic, granulocytic, lymphocytic, monocytic and thrombocytic series. © 2011 Brazil - BR Federal Government. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles. Source
Schloegel L.M.,Wildlife Trust |
Schloegel L.M.,Kingston University |
Ferreira C.M.,Fishery Institute |
James T.Y.,University of Michigan |
And 9 more authors.
Animal Conservation | Year: 2010
Global trade in the North American bullfrog Rana catesbeiana has been implicated in the introduction and spread of the amphibian pathogen Batrachochytrium dendrobatidis. Large-scale production of the North American bullfrog for human consumption has been ongoing since the early part of the 20th century, particularly in Brazil, a pioneer in bullfrog farming following its introduction in the 1930s. In order to determine whether bullfrogs introduced to Brazil and farmed for the food trade serve as reservoirs for amphibian disease, we tested individuals located in the Brazilian states of São Paulo and Pará to determine the prevalence of B. dendrobatidis infections. We were able to confirm B. dendrobatidis on five farms (78.5% infection prevalence overall) by PCR. Isolates were obtained from three of the five farms and genotyped at 17 loci using multilocus sequence typing. Five isolates from the Brazilian farms were genotypically similar to each other as well as to isolates from Central and South America. Isolates from farmed bullfrogs were more similar to isolates from introduced populations in Venezuela than those from the native range of the bullfrog in eastern North America. These results could have important implications for the origin and spread of B. dendrobatidis in Brazil, its neighboring regions and the conservation of native amphibian fauna. They may also suggest a potential for prior recombination within B. dendrobatidis in bullfrogs, which may have implications for the recent emergence of this pathogen. © 2009 The Authors. Journal compilation © 2009 The Zoological Society of London. Source
Da Silva W.F.,Histology Division and Coordinator of Comparative Hematology Laboratory |
Egami M.I.,Histology Division and Coordinator of Comparative Hematology Laboratory |
Santos A.A.,University of Sao Paulo |
Antoniazzi M.M.,Butantan Institute |
And 3 more authors.
Fish and Shellfish Immunology | Year: 2011
The cytochemical, immunocytochemical and ultrastructural characteristics of leukocytes and thrombocytes in the peripheral blood of the fat snook (Centropomus paralellus) - a fish occurring in Brazil - were investigated. The cytochemical methods were performed to demonstrate four enzymatic reactions - o-toluidine-hydrogen peroxide, naphtol AS-MX phosphate, naphtol AS-BI phosphate and alpha-naphtil acetate to detect myeloperoxidase (MPO), alkaline phosphatase (ALP), acid phosphatase (ACP) and non-specific esterase (α-NAE), respectively - and two non-enzymatic ones - Periodic-Acid Schiff (PAS) and Sudan black B (SBB) to detect the occurrence of glycogen and phospholipids, respectively. Immunocytochemical method utilizing polyclonal rabbit antibody against mammal metalloproteinases (MMPs) 2 and 9 were done. Standard method for Electron Microscopy (EM) was applied for the ultrastructural study. The cytochemical reactions were positive in neutrophils for MPO, ACP, α-NAE, glycogen and phospholipids; in lymphocytes for ACP and α-NAE; in monocytes for ACP and α-NAE and in thrombocytes for ACP, α-NAE and glycogen. Only neutrophils were positive for MMPs 2 and 9, and none of the cells studied were positive for ALP. Ultrastructurally: 1) neutrophil showed a spherical shape with a spherical, indented or lobulated euchromatic nucleus, and cytoplasm containing granules of varied sizes and mitochondria of varied shapes and sizes. The nucleus/cytoplasm relation and the size of granules suggest neutrophil maturation in peripheral blood; 2) lymphocytes showed partially heterochromatic nucleus and minimal cytoplasm; 3) monocytes had long cytoplasmic projections, an indented nucleus, evident nucleolus and cytoplasm with granules of varied sizes and vacuoles; 4) thrombocytes were predominantly elliptical or roughly spherical in shape, had a partially heterochromatic nucleus and cytoplasm containing electron-dense granules, intricate canalicular system and vacuoles occasionally holding phagocytic material. © 2011 Elsevier Ltd. Source
Schloegel L.M.,Ecohealth Alliance |
Toledo L.F.,University of Campinas |
Longcore J.E.,University of Maine, United States |
Greenspan S.E.,University of Maine, United States |
And 10 more authors.
Molecular Ecology | Year: 2012
Global amphibian declines are linked with the presence of specific, highly virulent genotypes of the emerging fungal disease chytridiomycosis caused by Batrachochytrium dendrobatidis (Bd) known as the global panzootic lineage (Bd-GPL). The global trade in amphibians for human consumption is suspected to have facilitated emergence of the disease, but evidence to support this is largely lacking. Here, we investigated the role the Lithobates catesbeianus (North American bullfrog) trade in spreading Bd genotypes by comparing strains associated with L. catesbeianus to a global panel using 36 sequenced loci from multiple chromosomal regions. Most bullfrogs were infected with Bd-GPL genotypes, but we also detected novel, highly divergent Bd genotypes (Bd-Brazil) from a live bullfrog in a US market and from native Brazilian anurans in the Atlantic Forest where bullfrogs are widely farmed. Sexual reproduction was also detected for the first time in Bd in the form of a hybrid genotype between the Bd-GPL and Bd-Brazil lineages in the Atlantic Forest. Despite the demonstration that ribosomal RNA types in Bd fail to undergo concerted evolution (over 20 sequence types may be found in a single strain), the Bd-GPL and Bd-Brazil lineages form largely separate clusters of related internal transcribed spacer (ITS) RNA sequences. Using ITS sequences, we then demonstrate the presence of Bd-Brazil in Japan, primarily on invasive L. catesbeianus. The finding that Bd is capable of sexual reproduction between panzootic and endemic genotypes emphasizes the risk of international wildlife trade as a source of additional Bd epizootics owing to hybridization. © 2012 Blackwell Publishing Ltd. Source