ABSTRACT
We have investigated the electronic response of single crystals of indium selenide by means of angle-resolved photoemission spectroscopy, electron energy loss spectroscopy and density functional theory. The loss spectrum of indium selenide shows the direct free exciton at ~1.3 eV and several other peaks, which do not exhibit dispersion with the momentum. The joint analysis of the experimental band structure and the density of states indicates that spectral features in the loss function are strictly related to single-particle transitions. These excitations cannot be considered as fully coherent plasmons and they are damped even in the optical limit, i.e. for small momenta. The comparison of the calculated symmetry-projected density of states with electron energy loss spectra enables the assignment of the spectral features to transitions between specific electronic states. Furthermore, the effects of ambient gases on the band structure and on the loss function have been probed.
ABSTRACT
The aim of this study was to elucidate the redox effects of Thiophanate methyl (MT) in the rat liver and kidney. Our results showed, after 3 days of MT injection (700 mg/kg), an increase in malondialdehyde (MDA), hydrogen peroxide and advanced oxidation protein products levels. Glutathione peroxidase and superoxide dismutase activities were also remarkably increased in the liver but decrease in the kidney. Glutathione and vitamin C values were significantly reduced. The changes in biochemical parameters were substantiated by histological and molecular data. A smear without ladder formation on agarose gel was shown, indicating random DNA degradation in the liver and the kidney of MT treated rats. The increase in cyclooxygenase-2 gene expression, marker of inflammation, and an increase in genes expression of glutathione peroxidase and superoxide dismutase in liver and their decrease in the kidney were also occurred after MT exposure. These data confirmed the pro-oxidant and genotoxic effects of this fungicide.
Subject(s)
Kidney/drug effects , Liver/drug effects , Thiophanate/toxicity , Toxicity Tests, Acute/methods , Animals , Ascorbic Acid/metabolism , DNA Fragmentation/drug effects , Dose-Response Relationship, Drug , Fungicides, Industrial/administration & dosage , Fungicides, Industrial/toxicity , Gene Expression/drug effects , Glutathione/metabolism , Glutathione Peroxidase/genetics , Glutathione Peroxidase/metabolism , Hydrogen Peroxide/metabolism , Injections, Intraperitoneal , Kidney/metabolism , Kidney/pathology , Lethal Dose 50 , Liver/metabolism , Liver/pathology , Male , Malondialdehyde/metabolism , Oxidation-Reduction/drug effects , Oxidative Stress/drug effects , Protein Carbonylation/drug effects , Rats, Wistar , Reactive Oxygen Species/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Superoxide Dismutase/genetics , Superoxide Dismutase/metabolism , Thiophanate/administration & dosageABSTRACT
Lead (Pb) is a highly toxic metal present in the environment. It causes disturbances of several functions, including hematologic, renal, reproductive and nervous ones. Preventive or curative use of medicinal plants against these disorders may be a promising and safe therapeutic strategy. This study evaluated the hepatic toxic effects of prenatal exposure to lead in rats and the possible protective effect of dandelion (Taraxacum officinale) added to the diet. Female rats were given a normal diet (control) or a diet enriched with dandelion (treated). In addition, lead acetate was administered to half of the rats through drinking water from the 5th day of gestation until the 14th day postpartum. Lead toxicity was evaluated in their offspring by measuring body and liver weights, plasma biochemical parameters, liver damage, as well as protein content and activities of antioxidant enzymes in the liver tissues. Lead poisoning of mothers caused lead deposition in blood and stomach of their pups as well as hepatic tissue damages. Moreover, significant decreases in liver weight and protein content were found. Lead treatment caused oxidative stress and marked changes in the activity of antioxidant enzymes. However, no damages or biochemical changes were observed in puppies from the rats co-treated with lead and dandelion. These results indicate that supplementation of pregnant and lactating rats with dandelion protects their offspring against lead poisoning, likely through reduction of oxidative stress and liver damages.
Subject(s)
Chemical and Drug Induced Liver Injury/drug therapy , Lead/toxicity , Plant Extracts/pharmacology , Prenatal Exposure Delayed Effects/drug therapy , Taraxacum/chemistry , Animals , Animals, Newborn , Catalase/metabolism , Chemical and Drug Induced Liver Injury/etiology , Diet , Female , Lead/administration & dosage , Lipid Peroxidation/drug effects , Liver/drug effects , Liver/metabolism , Liver/pathology , Male , Organ Size/drug effects , Oxidative Stress/drug effects , Phytotherapy/methods , Plant Extracts/administration & dosage , Pregnancy , Protective Agents/administration & dosage , Protective Agents/pharmacology , Rats , Superoxide Dismutase/metabolismABSTRACT
Lead is a toxic metal that induces a wide range of biochemical and physiological effects. The present investigation was designed at evaluating the toxic effects of a prenatal exposure to lead of mothers on hepatic tissue of newborn rats, and potent protective effects of spirulina. Female rats were randomly divided into 4 groups which were given a normal diet (control),a diet enriched with spirulina (S), lead acetate administered through drinking water (Pb), or a diet enriched with spirulina and lead contaminated water (S Pb), respectively. The duration of treatments was from the 5th day of gestation to 14 days postpartum. Lead toxicity was assessed by measuring body and liver weights, blood and stomach lead levels, hepatic DNA, RNA and protein amounts, blood enzyme activities (AST and ALT), as well as lipid peroxidation level and activities of antioxidant enzymes in hepatic tissues of neonates. Lead intoxication of mothers caused reduction of liver weight as well as of hepatic DNA, mRNA and protein levels in newborns. Moreover, oxidative stress and changes in antioxidant enzyme activities were recorded. Conversely, supplementation of mothers with spirulina mitigated these effects induced by lead. These results substantiated the potential hepatoprotective and antioxidant activity of spirulina.
Subject(s)
Lead/toxicity , Liver/pathology , Oxidative Stress/drug effects , Protective Agents/pharmacology , Spirulina/chemistry , Animals , Animals, Newborn , Antioxidants/metabolism , Body Weight/drug effects , Calcium/metabolism , DNA/metabolism , Feeding Behavior/drug effects , Gastric Mucosa/metabolism , Lead/metabolism , Lipid Peroxidation/drug effects , Liver/drug effects , Liver/enzymology , Organ Size/drug effects , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats, Wistar , Thiobarbituric Acid Reactive Substances/metabolism , Transaminases/bloodABSTRACT
The objective of this study was to investigate the propensity of potassium bromate (KBrO3) to induce oxidative stress in blood and bone of adult mice and its possible attenuation by vanillin. Our results demonstrated, after KBrO3 treatment, a decrease of red blood cells and hemoglobin and a significant increase of white blood cell. A decrease in plasma levels of folic acid, vitamin B12 and iron was also noted. Interestingly, an increase of lipid peroxidation, hydroperoxides, hydrogen peroxide, advanced oxidation protein products and protein carbonyl levels in erythrocytes and bone was observed, while superoxide dismutase, catalase and glutathione peroxidase activities and glutathione, non-protein thiol and vitamin C levels were decreased. KBrO3 treatment resulted in blood and bone DNA fragmentation, a hallmark of genotoxicity-KBrO3-induced, with reduction of DNA levels. Calcium and phosphorus levels showed a decrease in the bone and an increase in the plasma after KBrO3 treatment. These biochemical alterations were accompanied by histological changes in the blood smear and bone tissue. Treatment with vanillin improved the histopathological, hematotoxic and genotoxic effects induced by KBrO3. The results showed, for the first time, that the vanillin possesses a potent protective effect against the oxidative stress and genotoxicity in bone and blood of KBrO3-treated mice.
