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Objective: To investigate the effect of Cannabis sativa extract on the development of neuroand hepato-toxicity caused by malathion injection in rats. Methods: The extract of Cannabis sativa was obtained from the plant resin by chloroform treatment. Δ~9-Tetrahydrocannabinol content of the extract(20%) was quantified using gas chromatography–mass spectrometry. The doses of cannabis extract were expressed as Δ~9-tetrahydrocannabinol content of 10 or 20 mg/kg. Malathion(150 mg/kg) was intraperitoneally administered followed after 30 min by the cannabis extract(10 or 20 mg/kg, subcutaneously). Rats were euthanized 4 h later. Malondialdehyde(MDA), reduced glutathione(GSH), nitric oxide and paraoxonase-1(PON-1) activity were determined in brain and liver. Brain 5-lipoxygenase and butyrylcholinesterase(BChE) activity were measured as well. Histopathological examination of brain and liver tissue was also performed. Results: Compared to controls, malathion resulted in increased oxidative stress in brain and liver. MDA and nitric oxide concentrations were significantly increased(P0.05) and GSH significantly decreased with respect to control levels(P0.05). Malathion also significantly inhibited PON-1 and BChE activities but had no effect on brain 5-lipoxygenase. Brain MDA concentrations were not altered by cannabis treatment. Cannabis at 20 mg/kg, however, caused significant increase in nitric oxide and restored the GSH and PON-1 activity. Brain BChE activity significantly decreased by 26.1%(P0.05) after treatment with 10 mg/kg cannabis. Cannabis showed no effect on brain 5-lipoxygenase. On the other hand, rats treated with cannabis exhibited significantly higher levels of liver MDA, nitric oxide and PON-1 activity compared with the malathion control group. Rats treated with only malathion exhibited spongiform changes, neuronal damage in the cerebral cortex and degeneration of some Purkinje cells in the cerebellum. There were also hepatic vacuolar degeneration and dilated and congested portal vein. These histopthological changes induced by malathion in brain and liver were reduced to great extent by cannabis administration at 20 mg/kg. Conclusions: Our data suggest that acute treatment with cannabis alleviates the malathion-induced brain and hepatic injury in rats possibly by maintaining the levels of GSH and PON-1 activity.  相似文献   
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Family: Ascaridae as a whole is distributed among Africa and adjacent regions and in many areas of the world. The nematode Ascaridia galli is one of the most pathogenic and economically important parasites of poultry. The adult affect the small intestine of the hosts feeding on digested food materials. Its control costs million dollars annually. The genomic DNA was extracted from nematode parasites, A. galli, from specific host, native chickens. The polymerase chain reaction (PCR) was applied to ensure that the DNA content aids in the further studies. Two primers were used in the PCR reactions. The two primers were screened, only the second primer gave total amplified fragment markers 818 bp. The gene sequences obtained from Egyptian A. galli was compared with another one of accession number (AY587609) showing that the sequence was similar in some points from 346 to 1244 sequence, to make a phylogenetic relationships of A. galli with other nematodes on the data base showing that it was to some extent similar to Heterorhabditis spp.  相似文献   
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Scorpion envenomation is a health problem in children in tropical and subtropical regions. The aim of this study was to evaluate demographic and clinical characteristics as well as outcomes in referred children to Assiut University Children Hospital during the year 2012 with a history of scorpion sting. The medical files of these patients were reviewed retrospectively for demographic data, time and site of biting, and clinical manifestations. Laboratory investigations of the patients were reviewed for complete blood count (CBC), liver function tests, creatinine phosphokinase (CPK), lactate dehydrogenase (LDH), arterial blood gases, and serum electrolytes. Results showed 111 children with a history of scorpion sting; 69 males and 42 females with a median age of 5 years. Out of the studied patients, 53.2 % were classified as class III of clinical severity with recorded pulmonary edema in 33.3 %, cardiogenic shock in 46.8 %, and severe neurological manifestations in 22.8 %. Twelve patients (10.8 %) were classified as class II with mild systemic manifestations, and 36 % of the patients were classified as class I with only local reaction. Outcomes of these patients were discharge without sequelae in 55.8 %, discharge with sequelae in 26.1 %, and death in 18.1 %. Conclusion: more than half of stung children had a severe clinical presentation and about one fifth died. Aggressive treatment regimens are recommended for such patients to improve the outcome.  相似文献   
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