Ograniczanie wyników

Czasopisma help
Autorzy help
Lata help
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 72

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 4 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 4 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
Zbadano wpływ podania chlorfenwinfosu w jednorazowej dużej dawce na aktywność enzymów antyoksydacyjnych i stężenie diadehydu malonowego we krwi szczurów.
Zbadano wpływ podania chlorfenwinfosu na aktywność enzymów wątrobowych w surowicy krwi i homogenacie wątroby szczura, 48 h po podaniu tego związku w dawce jednorazowej.
The aim of this study was to investigate the effect of chlorfenvinphos administered at a single dose of 0.02 LD50 on the activity of serum of liver damage indicatory enzymes, such as β-glucoronidase (BGR), acid phosphatase (AcP) and alanine and aspartate aminotransferases (ALT and AST), as well as on the activities of superoxide dismutase (SOD) and catalase (CAT) in erythrocytes and liver. The animals were divided into two groups: the control group, which received oil, and the experimental groups, which received oil solution of chlorfenvinphos at a dose of 0.02 LD50. After 1, 24 and 48 hours of intoxication with chlorfenvinphos the blood samples were collected and livers were quickly removed. This study indicates that acute intoxication with chlorfenvinphos administered at a dose of 0.02 LD50 leads to liver function disturbances, which is a likely result of increased generation of reactive oxygen species.
This study was intendent to examine if N-acetylcysteine (NAC) changes liver GSH levels and influences ChE serum activity in rats intoxicated with chlorfenvinphos. The studies were conducted on male Wistar rats of 200±20 g body weight. One group of rats was pretreated with 0.1% water solution of NAC. NAC was administered in drinking water 24h before intoxication. The control groups received oil intragastrically by stomach tube in the amount of 0.1ml/100g (I), immediately or after NAC pretreatment. The experimental groups received oil solution of chlorfenvinphos in a dose of 0.02 LD50 or 0.1 LD50 immediately or after pretreatment with NAC. One and 24 hours after intoxication with chlorfenvinphos (or after NAC pretreatment) the blood samples were collected and livers were quickly removed and placed in iced 0.9% NaCl containing 0.16 mg/ml heparin. ChE serum activity and GSH level were measured. The results of this study demonstrated the changes in serum ChE activity and liver glutathione levels in the rats after administration of chlorfenvinphos at single doses. The results reported here indicate that NAC influences a decreased level of GSH in the liver of chlorfenvinphos-intoxicated rats and does not prevent ChE inhibition.
The aim of this paper was to examine the effects of chorfenvinphos on serum concentrations of transition metals, hydrogen peroxide and malondialdehyde (a lipid peroxidation index), and on the activity of superoxide dismutase in erythrocytes. Male Wistar rats were treated with vehicle or 0.02, 0.1 and 0.5 x LD50 of chlorfenvinphos and samples were collected at 1, 24 and 48 hr after treatment. The experiments were approved by the Local Ethics Committee. We demonstrated a decreased concentration of copper serum, which is accompanied by the increased activity of superoxide dismutase. The changes observed in the concentrations of copper can be explained by its displacement from serum to erythrocytes. We also observed increased levels of zinc serum (after intoxication with CVP at doses of 0.02 and 0.1 x LD50) and iron, as well as enhancement in hydrogen peroxide serum and malondialdehyde concentration. The changes in serum Zn concentration probably resulting from cellular membrane damage and the increase in serum iron concentration, is probably caused by its release from haemoglobin. The changes of serum Fe levels seems to have no effect on lipid peroxidation. We concluded that in acute intoxication with chlorfenvinphos — organophosphorus insecticide, the non-cholinesterase mechanismes are involved.
Cell metabolism in organisms which use oxygen as a source of energy is closely associated with the generation and action of free oxygen radicals and their derivatives. Extra- and intracellular substances that are antioxidative in nature prevent overproduction of radicals and protect against propagation of peroxidative reactions. The list of compounds which can be treated as antioxidants becomes elongated. Many classifications of these compounds are used, of which the most common is the division according to their nature into enzymatic and non-enzymatic, according to their environment or the way they react with FOR. Enzymatic antioxidants include: superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase. Non-enzymatic antioxidants are: vitamin E, vitamin C, glutathione, carotenes and retinols, and some transition metals (Zn, Cu and Se). The balance between the actions of these two groups of compounds determines normal functioning of the organism. Impairment of the balance between pro- and antioxidative processes in the organism is called anitoxidative stress and may be induced by intensified reactions involving FOR and by depressed activity/concentration of antioxidants. It seems, however, that irrespective of the cause, oxidative stress is likely to result in many diseases.
Chlorfenvinphos is an organophosphate insecticide widely used alone or in combination in Poland. In the present study, the influence of chlorfenvinphos on the activity of mitochondrial antioxidative system as well as hydrogen peroxide concentration was examinated. The experiments were conducted on male Wistar rats of 180±20g body weight. The animals were divided into two groups: the control group, which received oil intragastrically by stomach tube and the experimental groups, which received oil solution of chlorfenvinphos in doses of 0.02 LD50, 0.1 LD50 or 0.5 LD50. After 1, 24, 48 hours the livers were quickly removed. Liver mitochondria were isolated as described elsewhere. Glutathione peroxidase, superoxide dismutase, isocitrate dehydrogenase activity as well as reduced glutathione and hydrogen peroxide concentrations were determined in liver mitochondria using BIOXYTECH Assay kits produced by OXIS International, Inc., Portland, USA. The results of this work indicate that chlorfenvinphos induces oxidative stress to rat liver mitochondria. In acute chlorfenvinphos intoxication, we demonstrated that the key role in the oxidative mitochondrial damage play MnSOD and GSH pool, as well as accumulation of hydrogen peroxide.
Chlorfenvinphos, 2-chloro-1-(2,4-dichlorofenyl)vinyl diethyl phosphate, is an organophos-phate insecticide widely used in Poland singly or in mixture. The present study was undertaken to determine chlorfenvinphos-induced lipid peroxidation and to show whether acute intoxication with chlorfenvinphos alters the antioxidant system in the erythrocytes and serum. The study was conducted on male Wistar rats divided into two groups. The animals of control group were given olive oil intragastrically by a stomach tube, the animals of experimental group received oil solution of chlorfenvinphos (CVP) at a dose of 0.02, 0.1 or 0.5LD50. The blood was collected via heart puncture at the 1st, 24th and 48th hour after treatment. We determined the erythrocytes concentration of glutathione, the activities of glutathione peroxidase, glutathione reductase and glucose-6-phosphate dehydrogenase as well as the serum concentration of ascorbic acid, á-to-copherol and malondialdehyde. We observed the stimulation of enzymatic and nonenzymatic antioxi-dant system and lipid peroxidation in the erythrocytes and serum of chlorfenvinphos intoxicated rats.
The aim of this study was to determine the effect of acute intoxication with chlorfenvinphos on the liver reduced glutathione (GSH) level and the activities of two enzymes involved in glutathione metabolism, as well as the activity of catalase (CAT), glucose-6-phosphate dehydrogenase (G6PDH) and the level of liver hydrogen peroxide. The concentration of malondialdehyde (MDA) was determined as lipid peroxidation index. Rats were divided into two groups: the control group, which received oil intragastrically by stomach tube, and the experimental groups, which received oil solution of chlorfenvinphos (CVP) in doses of 0.02 LD50, 0.1 LD50 or 0.5 LD50. After 1, 24, 48 hours of intoxication with chlorfenvinphos, the livers were quickly removed and placed in iced 0.9% NaCl containing 0.16 mg/ml heparin. The liver glutathione peroxidase (GPx) and reductase (GR) activities as well as GSH and hydrogen peroxide levels were determined using Bioxytech Assay kits. CAT activity was determined by Aebi method, G6PDH activity was measured using Sigma Assay kit. MDA level was determined by Buege and Aust method. The changes of examined parameters of antioxidative system as well as lipid peroxidation index were found. The correlation between MDA concentration and the elements of enzymatic and non-enzymatic antioxidative system was determined. A statistically significant correlation was found only between MDA level and G6PDH activity. In conclusion, it is suggested that G6PDH play a key role in the defence against oxidative stress induced by intoxication with chlorfenvinphos.
The influence of zinc on the activity of antioxidant enzymes in the blood of rats intoxicated with lead was studied. Exposure to lead at the concentration of 500 mg/dm3 for 6 weeks caused a decrease in the activities of SOD, GSH-PX and GR as well as an increase in MDA concentrations in the serum. Zinc at the concentration of 60 mg/dm3 administered for a period of 2 weeks after exposure to cadmium reduced the effects of toxic action of lead leading to a normalization of the activities of SOD and GR in the blood as well as MDA concentration in the serum.
The aim of this paper was to examine the activity of lysosomal enzymes after intoxication with chlorfenvinvos and dichlorvos - phosphoorganic insecticides. Investigations were carried out on male Wistar rats weighing 180-230 g. Rats were divided into two groups: control and treated. Rats of treated group were receiving oil solution of chlorfenvinvos at doses of 0.5 LD50 or 0.1 LD5(), determinations were performed after 1 and 24 hours after treatment or dichlorvos in the dose equal to 0.5 LD50 estimations were performed after 1 h only. Rats of control group were given equivalent volume of oil. Activities of beta-glucuronidase and acid phosphatase in the blood serum and lysosomal fraction of rat liver homogenate were determined. It was found that the level of ChE inhibition and increase of BGR activity in the serum were dependant on chemical structure of used compound, dose and time after treatment. It was observed that increase of hydrolases activities in serum was accompanied by the decrease in its activity in the lysosomal fraction of liver homogenate.
The aim of the present study was to investigate the effects of cadmium (Cd) (5 and 50 mg Cd/l in drinking water) and ethyl alcohol (ethanol, EtOH) (5 g EtOH/kg b.wt., intragastrically), administered alone or simultaneously, on the concentrations of pro-inflammatory (interleukin-1, IL-1?; interleukin-6, IL-6; tumor necrosis factor-?, TNF? and interferon ?, INF?) and anti-inflammatory (interleukin-4, IL-4) cytokines in the serum of rats. In order to estimate the involvement of Cd- or/and EtOH-induced oxidative stress in damage to cytokines, the concentration of protein carbonyl groups (PC), as a marker of oxidative protein damage, was also determined. Exposure to 5 and 50 mg Cd/l, alone or in combination with EtOH, led to an increase in the serum concentrations of IL-1?, TNF? and INF? with a simultaneous decrease in IL-4 concentration, compared to the control. The concentration of IL-6 was elevated only after administration of 50 mg Cd/l, both alone and in combination with EtOH. The exposure to EtOH alone resulted in increased concentrations of TNF? and INF?, as well as in decreased concentrations of IL-4. In rats co-exposed to Cd and EtOH, the changes observed in the concentrations of the cytokines, except in IL-6, were more advanced, compared to the animals treated with these xenobiotics alone. Exposure to Cd and EtOH, both alone and in combination, caused an increase in the serum PC concentration. The concentration of PC positively correlated with the concentrations of IL-1?, IL- 6, TNF? and INF? and negatively with IL-4 concentration. The results suggest that changes in the cytokines examined are more enhanced after combined exposure to Cd and EtOH, especially at higher Cd dosage. Moreover, it can be hypothesized that oxidative stress may be involved in the mechanism leading to changes in the concentration of cytokines after exposure to Cd and EtOH alone and in combination.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 4 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.