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This study aimed to examine the side effects of selected neonicotinoids (Acetamiprid, Aceta, and Imidacloprid, Imid) on Oreochromis niloticus juveniles. The acute toxicity, Probit method, revealed an LC50 of 195.81 and 150.76 ppm for Aceta/96 h and Imid/72 h respectively. The fish were divided into three groups that were exposed, for 21 days (n?=?5/replicate), to 1/10 of the LC50 of either neonicotinoids, however, the third was an unexposed control group. Results of erythrocytic micronucleus (MN), and nuclear abnormalities (NA) showed that Aceta and Imid exposure caused a significant (p?<?0.05) increase in MN by?~?2.2 and?~?10 folds, respectively relative to control. NAs occurred at the order of kidney-shaped?>?budding?>?binucleated in Aceta, however, budding?>?binucleated?>?kidney-shaped was noticed in the Imid group. Histopathological changes in gills, liver, and muscles were observed significantly in both exposed groups with more severity in the Imid group. Collectively, Aceta and Imid have potential genotoxicity and histopathological alterations in O. niloticus.

  相似文献   
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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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Hepatocellular carcinoma (HCC), represents more than 85% of liver cancers. The diagnosis of HCC may be delayed due to the absence of early, sensitive and specific biomarkers. This study was conducted to investigate whether the expression of thioredoxin (Trx) and glutaredoxin (Grx) is helpful for HCC diagnosis in an experimental model. Twenty male albino rats were equally divided into two groups (HCC and control). Hepatocarcinogenesis was performed by single intraperitoneal (i.p) injection of 200?mg/kg of diethylnitrosamine (DENA). Two weeks later, 0.05% of phenobarbital (PB) was supplied in the drinking water for other 14 weeks. HCC was diagnosed by measuring serum alpha-fetoprotein (AFP) level and histopathological examination. Our results found that hepatic indices alanine transaminase (ALT), aspartate transaminase (AST), total bilirubin were elevated but decreased total protein level. Lipid peroxidation was elevated through increasing hepatic content of MDA with decreased antioxidant parameters like hepatic SOD, CAT activities and GSH. The current study also found that Trx and Grx tissue genes were overexpressed in HCC group significantly, compared to control group. This study substantiated that increased expression of these enzymes may be predictive of outcomes in HCC.  相似文献   
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Helicobacter pylori was incriminated as an etiological factor of rosacea. However, there is still controversy about this association. We conducted a comparative study in order to assess the role of H. pylori in rosacea patients who had dyspeptic symptoms. The study included 68 patients and 54 controls. Screening for H. pylori was performed and positive cases were referred for gastric endoscopy. The inflammatory response and bacterial density were evaluated in gastric biopsy. H. pylori vacA alleles, cagA and iceA genotypes were assessed by polymerase chain reaction. We found that 49 rosacea (72%) and 25 controls (46.3%) were infected with H. pylori. Thirty‐one rosacea cases were papulopustular (PPR) while 18 were erythematotelangiectatic (ETR). Gastric ulceration was higher in PPR cases (38.7%) than ETR (11.1%) and controls (12%). A significant inflammatory reaction was observed more in PPR cases (74.2%) compared with 44.4% in ETR (P = 0.04) and 44% in controls (P = 0.02). Analysis of H. pylori genotypes revealed that vacA s1m1 was more identified in PPR cases (54.8%) compared with 22.2% in ETR (P = 0.03) and 16% in controls (P = 0.003). There was a significant elevation of cagA/vacA s1m1 positivity in PPR cases. After the eradication regimen of H. pylori, a significant improvement (P < 0.05) was observed in 15 out of 27 PPR cases (55.6%) compared with three out of 17 ETR (17.6%). We concluded that H. pylori has a significant role in rosacea patients who had dyspeptic symptoms. The PPR type is more influenced by H. pylori and this is regarded as being because of certain virulent strains that increase the inflammatory response in gastric mucosa and also in cutaneous lesions.  相似文献   
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Background  

Neutrophil elastase level/activity is elevated in a variety of diseases such as atherosclerosis, systolic hypertension and obstructive pulmonary disease. It is unknown whether obese individuals with prehypertension also have elevated neutrophil elastase, and if so, whether it has a deleterious effect on pulmonary function. Objectives: To determine neutrophil elastase levels in obese prehypertensive women and investigate correlations with pulmonary function tests.  相似文献   
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A series of new fluoroquinolone conjugates 8a–g and 9a–f were synthesized via benzotriazole‐mediated synthetic approach with good yield and purity. Some of the synthesized analogs exhibited significant antibacterial properties against Escherichia coli and Staphylococcus aureus with potency higher than that of the parent drugs through in vitro standard bioassay procedure (conjugates 8c and 8d reveal antimicrobial properties with potency 1.9, 61.9, 20.7 and 2.4, 37.1, 8.3 folds relative to the parent antibiotic 6 against E. coli, S. aureus, and Enterococcus faecalis, respectively). The observed experimental data were supported by enzymatic DNA gyrase inhibitory property. Developed BMLR‐QSAR model validates the observed experimental data and recognizes the parameters responsible for the enhanced antibacterial properties.  相似文献   
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