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2.
Heliyon ; 8(12): e12405, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36590486

RESUMO

This study was conducted to investigate the effects of Eucalyptus globulus oil and methanolic extract of Ricinus communis seeds on the reproductive biology of the land snail Theba pisana. For this purpose, the snails were exposed to different concentrations of these plant extracts for six weeks. Rates of oviposition, hatching percentages, reproductive hormones and the histological structures of the hermaphrodite gland were estimated. Antioxidant enzymes were also estimated. The obtained results revealed that all tested concentrations of both tested natural products exerted hazardous effects on exposed snails. The mean egg number/snail treated with 2% E. globulus and R. communis were significantly decreased to 22 and 14 eggs respectively compared to 79 eggs for control. The hatching rates were dramatically decreased with increasing concentrations of both products. 2% of R. communis extract caused highly significant decrease in the activities of CAT, SOD, GST and MDA antioxidant enzymes while the same concentration of Eucalyptus oil resulted in elevations of CAT and SOD activities and significantly decreased GST and MDA activities. Levels of reproductive hormones were greatly disrupted and the histological structures of hermaphrodite acini as well as various developmental stages of spermatogenesis and oogenesis of treated snails were strictly spoiled.

3.
Food Chem Toxicol ; 52: 42-52, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23127602

RESUMO

This study aims to investigate the fate and histopathological effects of ethion on selected organs of the crayfish, Procamabrus clarkii. Crayfish were exposed to 1 mg l(-1) (14)C-ethion and the concentrations of ethion and its possible degradation products were measured in water and different organs of the crayfish over both the exposure and recovery periods. Chromatographic analysis revealed that ethion was degraded into ethion monooxon, ethion dioxon, O,O-diethyl phosphorothioate, O-ethyl phosphorothioate and one unknown compound. At the end of exposure period, ethion was accumulated in different organs of the crayfish especially in the hepatopancreas and gills. Following the transfer of crayfish to clean water for seven days, the concentration of insecticide residues were decreased in both the hepatopancreas and gills suggesting that these organs play an important role in elimination of ethion. On the other hand, the exposure of the crayfish to » 96 h-LC(50) (0.36 mg l(-1)) of ethion caused extensive ultrastructural alterations to both hepatopancreas and gill epithelial cells. In the hepatopancreas, the most notable pathological features included vacuolation, degradation and distinct cell lysis. In the gill epithelium, the histopathological alterations included infiltration of hemocytes, cytoplasmic vacuolation and a decrease in the number of basal plasma membrane infoldings.


Assuntos
Astacoidea/efeitos dos fármacos , Inseticidas/farmacocinética , Compostos Organotiofosforados/farmacocinética , Compostos Organotiofosforados/toxicidade , Poluentes Químicos da Água/farmacocinética , Animais , Exposição Ambiental , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Brânquias/patologia , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/metabolismo , Hepatopâncreas/patologia , Organotiofosfatos/metabolismo , Compostos Organotiofosforados/metabolismo , Distribuição Tecidual , Testes de Toxicidade Aguda
4.
Aquat Toxicol ; 77(2): 143-52, 2006 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-16413619

RESUMO

The present study was undertaken to elucidate the cellular mechanisms, which govern metal sequestration and detoxification in gastropods. For this purpose the pond snail, Lymnaea stagnalis was exposed to environmentally relevant concentrations of three species of metals (Al, Zn and Cd) for 30 days and the localization and fate of these metals were followed in different tissues of the snails. The measurement of relative distribution of metals between tissues revealed that the digestive gland and kidney account for most of the accumulated metals. Al and Cd (non-essential metals) were redistributed to the digestive gland, possibly because of the presence of specific binding entities in the digestive glands of the herein species. This study focuses on the role of intracellular metal-containing granules on metal sequestration. Three main types of granules were identified in the digestive gland cells namely small, green and yellow granules. The morphological examination and the progressive accumulation of elements within these granules revealed that they are developmental stages with the yellow granule being the mature one. The total number of these granules was found to be significantly increased upon exposure of the snails to Al only. This increase may be a response to the large amount of Al that is accumulated through feeding route of this grazing snail. X-ray microanalysis (XRMA) revealed that metals were localized in all three types of digestive gland granules. The increased amount of ligands (P and S) in the granules may give evidence for their role in metal sequestration. Levels of Al and P were positively correlated in the digestive gland granules. It is possible that aluminium is bound to phosphorus to render it insoluble and so to both immobilize it within the lysosome and to be excreted in a highly insoluble form. On the other hand, both Zn and Cd induced marked upregulation of S in mature (yellow) granules by 26- and 11-folds, respectively. The lysosomal codeposition of S and either Cd or Zn in the lysosomal granules in addition to the increase in RER cisternae may indicate that the exposure to these metals could induce metallothionein synthesis in the cells. The microscopical examinations in the present study revealed that metal detoxification from the digestive gland cells may occur via faeces or via basal exocytosis towards hemocytes dispersed by the connective tissue in the visceral mass. In the kidney, one type of granules, the excretory concretions, was identified in the nephrocytes. The significant increase in the number of these concretions in the snail L. stagnalis upon exposure to metals may give further evidence for their role in metal excretion.


Assuntos
Lymnaea/metabolismo , Lisossomos/metabolismo , Metais/farmacologia , Metais/farmacocinética , Compostos de Alumínio/farmacocinética , Compostos de Alumínio/farmacologia , Análise de Variância , Animais , Cloreto de Cádmio/farmacocinética , Cloreto de Cádmio/farmacologia , Cloretos/farmacocinética , Cloretos/farmacologia , Grânulos Citoplasmáticos/efeitos dos fármacos , Sistema Digestório/química , Sistema Digestório/patologia , Microanálise por Sonda Eletrônica/veterinária , Exposição Ambiental , Rim/química , Rim/patologia , Lymnaea/efeitos dos fármacos , Lisossomos/ultraestrutura , Metais/análise , Microscopia Eletrônica de Transmissão/veterinária , Nitratos/farmacocinética , Nitratos/farmacologia , Fatores de Tempo , Distribuição Tecidual , Compostos de Zinco/farmacocinética , Compostos de Zinco/farmacologia
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