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Marilia O F Goulart - One of the best experts on this subject based on the ideXlab platform.
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activities of naphthoquinones against aedes aegypti linnaeus 1762 diptera culicidae vector of dengue and Biomphalaria glabrata say 1818 intermediate host of schistosoma mansoni
Acta Tropica, 2009Co-Authors: Karlos Al Ribeiro, Cenira Monteiro De Carvalho, Maria Teresa Molina, Estelita Pereira Lima, Eulogio Lopezmontero, Jose Rui M Reys, Maria Beatriz Farias De Oliveira, Antonio V Pinto, Antonio Euzebio Goulart Santana, Marilia O F GoulartAbstract:Larvicidal (against Aedes aegypti Linnaeus, 1762) and molluscicidal (against Biomphalaria glabrata Say, 1818) activities of several natural and synthetic naphthoquinones were measured, with significant results. The best larvicidal compound is 3-bromojuglone, while the better molluscicides are 2-bromo- and 3-bromo-5-acetoxy-1,4-naphthoquinones together with the 3-bromo-5-methoxy derivative. The present results reinforce the potential use of substituted hydroxyquinones, their salts and halogenated quinones as very promising compounds against 4th instar larves of Aedes aegypti, the vector of dengue and against adult snail of Biomphalaria glabrata.
John T. Sullivan - One of the best experts on this subject based on the ideXlab platform.
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Comparison of NMRI Schistosoma mansoni Infection in Three Susceptible Laboratory Albino Strains of Biomphalaria glabrata.
Journal of Parasitology, 2019Co-Authors: John T. SullivanAbstract:ABSTRACT Albino strains of Biomphalaria glabrata that are compatible with Schistosoma mansoni are commonly used to investigate snail-schistosome interactions, but whether they are all equally compa...
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Tissue invasion of laboratory-reared Biomphalaria glabrata by a harpacticoid copepod.
Journal of Invertebrate Pathology, 2011Co-Authors: John T. Sullivan, John T. YeungAbstract:Abstract Copepods were observed in the tissues of 3 of 23 Biomphalaria glabrata snails examined histologically. All were heavily encapsulated by hemocytes and were dead. The copepods are most likely members of the order Harpacticoida, based on external morphology. This tissue invasion appears to be accidental rather than symbiotic or predatory, but could be a cause of observed mortality in laboratory snail colonies.
Karlos Al Ribeiro - One of the best experts on this subject based on the ideXlab platform.
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activities of naphthoquinones against aedes aegypti linnaeus 1762 diptera culicidae vector of dengue and Biomphalaria glabrata say 1818 intermediate host of schistosoma mansoni
Acta Tropica, 2009Co-Authors: Karlos Al Ribeiro, Cenira Monteiro De Carvalho, Maria Teresa Molina, Estelita Pereira Lima, Eulogio Lopezmontero, Jose Rui M Reys, Maria Beatriz Farias De Oliveira, Antonio V Pinto, Antonio Euzebio Goulart Santana, Marilia O F GoulartAbstract:Larvicidal (against Aedes aegypti Linnaeus, 1762) and molluscicidal (against Biomphalaria glabrata Say, 1818) activities of several natural and synthetic naphthoquinones were measured, with significant results. The best larvicidal compound is 3-bromojuglone, while the better molluscicides are 2-bromo- and 3-bromo-5-acetoxy-1,4-naphthoquinones together with the 3-bromo-5-methoxy derivative. The present results reinforce the potential use of substituted hydroxyquinones, their salts and halogenated quinones as very promising compounds against 4th instar larves of Aedes aegypti, the vector of dengue and against adult snail of Biomphalaria glabrata.
Wilhelm Becker - One of the best experts on this subject based on the ideXlab platform.
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Studies on the urea cycle of Biomphalaria glabrata during normal feeding activity, in starvation and with infection of schistosoma mansoni☆
Comparative Biochemistry and Physiology B, 2010Co-Authors: Hartwig Schmale, Wilhelm BeckerAbstract:1. 1. Ornithine carbamyltransferase (OCT, argininosuccinate lyase (ASL and arginase activity could be determined in hepatopancreas homogenates of Biomphalaria glabrata. The activities of the OCT of 99.8 ± 34.8 μmole/g hepatopancreas/hr and ASL of 0.45 ± 0.29 μmole/g hepatopancreas/hr are in accord with the values round in other molluscs; the arginase activity of 31.6 ± 31 μmole/g hepatopancreas/hr is ver low for a pulmonate. 2. 2. Carbamylphosphate and argininosuccinate synthetase activity could not be demonstrated in the hepatopancreas of Biomphalaria glabrata with photometric methods. The presence of a “carbamylphosphate phosphatase” and an “adenosine deaminase” intefered with the method of assay employed. 3. 3. The incorporation of 14C from NaH14CO3 in urea by intact hepatopancreas tissue in vitro is highly suggestive that a complete urea cycle exists in Biomphalaria glabrata. 4. 4. An ureolytic activity in Biomphalaria glabrata could be determined neither with hepatopancreas homogenates nor with intact tissue of hepatopancreas in vitro. 5. 5. Under the physiological conditions “5 days starvation”, “infected with Schistosoma mansoni” and “dry keeping at a humidity of 96%”, there is a significant increase in the activities of the studied urea cycle enzymes. Corresponding increased incorporation rates of 14CO2 from bicarbonate in urea by hepatopancreas in vitro could be measured in the above-mentioned conditions. 6. 6. The importance of the urea cycle for the NH3 detoxification of Biomphalaria glabrata is discussed.
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early mineralization in Biomphalaria glabrata microscopic and structural results
Journal of Molluscan Studies, 2003Co-Authors: Julia C Marxen, Wilhelm Becker, Doreen Finke, Bernd Hasse, Matthias EppleAbstract:The formation of the shell of Biomphalaria glabrata was studied in dissected embryos and egg masses with scanning electron microscopy, electron spectroscopic imaging (ESI), thermogravimetry, synchrotron powder diffraction and Ca K-edge X-ray absorption spectroscopy (EXAFS). The results show that shell formation starts by accumulation of calcium below the periostracum at an age of about 60 h. At first, amorphous calcium carbonate is precipitated. EXAFS studies reveal that an aragonitic structure is already present at a microscopic level in this amorphous precursor phase. The first crystalline phase (calcium carbonate in the form of aragonite) can be detected at an age of 72 h. It is concluded that amorphous calcium carbonate initially present is transformed into crystalline aragonite during embryonic development, without vaterite appearing as a potential intermediate.
Zilton A. Andrade - One of the best experts on this subject based on the ideXlab platform.
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On the origin of the Biomphalaria glabrata hemocytes
Memorias Do Instituto Oswaldo Cruz, 2006Co-Authors: Samaly Dos Santos Souza, Zilton A. AndradeAbstract:A histologic, morphometric and ultrastructural study performed on Biomphalaria glabrata submitted to infection with Schistosoma mansoni miracidia failed to provide significant evidences that the so-called amebocyte-producing organ (APO) is really the central organ for hemocyte production. In infected snails no general reactive changes appeared in the APO, the mitoses were seen only occasionally, and the possibility of cellular hyperplasia was ruled out by morphometric measurements. Under the electron microscope the APO cells presented an essentially epithelial structure, without features indicative of transition toward hemocytes. On the other hand, the present findings pointed to a multicentric origin for the mollusck hemocytes, as earlier studies had indicated. Dense foci of hemocyte collections appeared sometimes around disintegrating sporocysts and cercariae in several organs and tissues of the infected snails, including a curious accumulation of such cells inside the ventricular cavity of the heart. In the heart and other sites, features suggestive of transformation of vascular space endothelial lining cells into hemocytes were apparent. To some extent, the postulated multicentric origin for B. glabrata hemocytes recapitulates earlier embryologic findings in vertebrates, when mesenchymal vascular spaces generate the circulating and phagocytic blood cells.
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Behavior of Schistosoma mansoni-induced histopathological lesions in Biomphalaria glabrata submitted to ionizing radiation.
Revista Da Sociedade Brasileira De Medicina Tropical, 2004Co-Authors: Carine M. Azevedo, Claudia Maria Da Cunha Borges, Zilton A. AndradeAbstract:Present report demonstrates that repeated radiation of Schistosoma mansoni-infected Biomphalaria glabrata, totaling 15,000 rads, caused a sudden, albeit transient, suppression of cercarial shedding. Initially, sporocysts practically disappeared from the snail tissues. The more resistant developing cercariae presented nuclear clumping and vacuolation, before undergoing lysis. No host tissue reaction was evident at any time. Thirty-four days after the last irradiation, the snails resumed cercarial elimination. By that time numerous sporocysts and developing cercariae were detected, disseminated throughout snail tissues in a pattern similar to that of a highly malignant neoplasm, with no signs of host cellular reactions, which on the other hand were present in non-irradiated infected controls. The region of the ovo-testis was apparently destroyed after radiation, but returned to its normal appearance around 40 days after the last radiation. Ionizing radiation affected both host and parasite in S. mansoni-infected Biomphalaria glabrata, but the resulting impressive changes were soon reversed.
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A new method for fixing Biomphalaria glabrata for histologic studies, using shell perforation.
Memorias Do Instituto Oswaldo Cruz, 2002Co-Authors: L. Barbosa, Paulo Marcos Zech Coelho, Débora Negrão-corrêa, Zilton A. AndradeAbstract:A new technique for fixation of Biomphalaria glabrata for histologic studies is described. It consists in performing several external holes in the shell, before placing the entire snail into the fixative. It is a very practical and quick procedure that showed excellent results when compared to the usual techniques.
