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The role of the liver is the major site of detoxification and metabolism, so it was considered as a target organ in toxicological studies. The present study investigates the potential protective effects of Amphora coffeaeformis extract against hepatotoxic effects in African catfish, Clarias gariepinus induced by arsenic. The fish Clarias gariepinus was exposed to sub-lethal concentrations of arsenic; 19.2 and 38.3 mg/L (1/8 and 1/4 of 96h-LC50 value, 153.17 mg/L) for 15 days. Histopathological alterations of the liver were analyzed under light and transmission electron microscope (TEM). Using the light microscope, the alterations were hypertrophy and hyperplasia of hepatocytes, necrosis, melanomacrophage accumulation, lymphocytic aggregation and congested blood vessels as well as depletion in glycogen content. TEM investigation resulted in alterations in perichromatin granules that increased and progressively formed small clusters closely related with patches of heterochromatin. Also fractionation, dilation, and vesiculation of rough endoplasmic reticulum were observed in addition to mitochondrial hyperplasia, hypertrophy and cristolysis. Significant main effects were reported for glutathione and malondialdehyde levels (P< 0.05) after arsenic exposure. This arsenic-induced hepatotoxicity was improved with the dietary supplementation of Amphora. We concluded that Amphora extract can be used as a hepato-protective agent on arsenic-induced fish due to its biologically active components.

The role of the liver is the major site of detoxification and metabolism, so it was considered as a target organ in toxicological studies. The present study investigates the potential protective effects of Amphora coffeaeformis extract against hepatotoxic effects in African catfish, Clarias gariepinus induced by arsenic. The fish Clarias gariepinus was exposed to sub-lethal concentrations of arsenic; 19.2 and 38.3 mg/L (1/8 and 1/4 of 96h-LC50 value, 153.17 mg/L) for 15 days. Histopathological alterations of the liver were analyzed under light and transmission electron microscope (TEM). Using the light microscope, the alterations were hypertrophy and hyperplasia of hepatocytes, necrosis, melanomacrophage accumulation, lymphocytic aggregation and congested blood vessels as well as depletion in glycogen content. TEM investigation resulted in alterations in perichromatin granules that increased and progressively formed small clusters closely related with patches of heterochromatin. Also fractionation, dilation, and vesiculation of rough endoplasmic reticulum were observed in addition to mitochondrial hyperplasia, hypertrophy and cristolysis. Significant main effects were reported for glutathione and malondialdehyde levels (P< 0.05) after arsenic exposure. This arsenic-induced hepatotoxicity was improved with the dietary supplementation of Amphora. We concluded that Amphora extract can be used as a hepato-protective agent on arsenic-induced fish due to its biologically active components.

The role of the liver is the major site of detoxification and metabolism, so it was considered as a target organ in toxicological studies. The present study investigates the potential protective effects of Amphora coffeaeformis extract against hepatotoxic effects in African catfish, Clarias gariepinus induced by arsenic. The fish Clarias gariepinus was exposed to sub-lethal concentrations of arsenic; 19.2 and 38.3 mg/L (1/8 and 1/4 of 96h-LC50 value, 153.17 mg/L) for 15 days. Histopathological alterations of the liver were analyzed under light and transmission electron microscope (TEM). Using the light microscope, the alterations were hypertrophy and hyperplasia of hepatocytes, necrosis, melanomacrophage accumulation, lymphocytic aggregation and congested blood vessels as well as depletion in glycogen content. TEM investigation resulted in alterations in perichromatin granules that increased and progressively formed small clusters closely related with patches of heterochromatin. Also fractionation, dilation, and vesiculation of rough endoplasmic reticulum were observed in addition to mitochondrial hyperplasia, hypertrophy and cristolysis. Significant main effects were reported for glutathione and malondialdehyde levels (P< 0.05) after arsenic exposure. This arsenic-induced hepatotoxicity was improved with the dietary supplementation of Amphora. We concluded that Amphora extract can be used as a hepato-protective agent on arsenic-induced fish due to its biologically active components.

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Potentiometric equilibrium measurements have been made at 25±0.1 °C (μ=0.1 mol dm-3 KNO3) for the interaction of adenosine-5′-mono-, -di-, and-triphosphate (AMP, ADP, and ATP) and Ni(II) with biologically important secondary ligand acids (malic, maleic, succinic, tartaric, citric and oxalic acids) in a 1:1:1 ratio and the formation of various 1:1:1 mixed ligand complex species inferred from the potentiometric pH titration curves. Initial estimates of the formation constants of the resulting species and the acid dissociation constants of AMP, ADP, ATP and secondary ligand acid, have been refined with SUPERQUAD computer program. In some systems Δ log K values are positive, i.e. the ternary complexes are found to be more stable than the corresponding binary complexes. H-bond formation seems to be most effective in deciding the stability of the ternary complexes formed in solution. Stabilities of mixed ligand complexes increases in the order AMP<ADP<ATP. With respect to the secondary ligands, the formation constants of the mixed lignads complexes decrease in the order succinic>maleic>tartaric>malic>citric>oxalic acid. © 1993 Springer-Verlag.

Potentiometric equilibrium measurements have been made at 25±0.1°C (μ=0.1 mol dm-3 KNO3) for the interaction of adenosine-5′-mono-, -di- and -triphosphate (AMP, ADP and ATP) and Cu(II) with biologically important secondary ligand acids (malic, maleic, succinic, tartaric, citric and oxalic acids) in a 1:1:1 ratio and the formation of various 1:1:1 mixed ligand complex species inferred from the potentiometric pH titration curves. Initial estimates of the formation constants of the resulting species and the acid dissociation constants of AMP, ADP, ATP, and secondary ligand acid, have been refined with the SUPERQUAD computer program. In some systems Δlog K values are positive, i.e. the ternary complexes are found to be more stable than the corresponding binary complexes. In some Cu(II) ternary systems the interligand interactions between the coordinate ligands, possibly H bond formation, have been found to be most effective in deciding the stability of the ternary complexes formed in solution. Stabilities of mixed ligand complexes increase in the order AMP <ADP <ATP. With respect to the secondary ligands, the formation constants of the mixed ligand complexes decrease in the order succinic > maleic > tartaric > malic > citric > oxalic acid. © 1993 Springer-Verlag.

1:1 CT complexes formed between some crown polythioethers and π-electron acceptors (DDQ, TCNE and CHL) have been synthesized and characterized. Spectral characteristics and formation constants of the CT complexes have been measured at 25°C. The effects of donor molecular structure, π-acceptor electron affinity and solvent polarity on the stabilities of these CT complexes have been investigated and discussed. It is deduced that such complexes are of weak n-π type where the ground state wave function is described primarily by the nonbonding structure (D-A). Ionization potentials of the crown thioethers have been estimated from the CT transition energies. © 1993, Taylor & Francis Group, LLC. All rights reserved.