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91.
Lambda-cyhalothrin is a synthetic pyrethroid insecticide used worldwide in agriculture, home pest control, protection of foodstuff and disease vector control. The objective of this study was to investigate the propensity of lambda-cyhalothrin (LTC) to induce oxidative stress, changes in biochemical parameters and enzyme activities in the kidney of male rats and its possible attenuation by Vitamin C (vit C). Renal function, histopathology, tissue malondialdehyde (MDA), protein carbonyl (PCO) levels, antioxidant enzyme activities and reduced glutathione (GSH) levels were evaluated. Exposure of rats to lambda-cyhalothrin, during 3 weeks, caused a significant increase in kidney MDA and protein carbonyl levels (p<0.01) as compared to controls. Co-administration of vitamin C was effective in reducing MDA and PCO levels. The kidney of LTC-treated rats exhibited severe vacuolations, cells infiltration and widened tubular lumen. The activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione-S-transferase (GST) were significantly decreased due to lambda-cyhalothrin exposure. Co-administration of vitamin C ameliorated the increase in enzymatic activities of aminotransferases (AST and ALT), lactate dehydrogenase (LDH), creatinine and urea levels and improved the antioxidant status.These data indicated the protective role of ascorbic acid against lambda-cyhalothrin-induced nephrotoxicity and suggested a significant contribution of its antioxidant property to these beneficial effects.  相似文献   
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Cryptococcal meningitis infections cause high mortality rates among HIV‐infected patients in Sub‐Saharan Africa. The high incidences of cryptococcal infections may be attributed to common environmental sources which, if identified, could lead to institution of appropriate control strategies. To determine the genotypes of Cryptococcus gattii/C. neoformans‐ species complex from Nairobi, Kenya, 123 clinical and environmental isolates were characterised. Typing was done using orotidine monophosphate pyrophosphorylase (URA5) gene restriction fragment length polymorphism (URA5‐RFLP). The majority of the isolates [105/123; 85.4%] were C. neoformans genotype (AFLPI/VNI) and 1.6% AFLP1A/VNB/VNII, whereas (13%) were C. gattii (AFLP4/VGI). This is the first report on the genotypes of C. gattii/C. neoformans species complex from clinical and environmental sources in Nairobi, Kenya and the isolation of C. gattii genotype AFLP4/VGI from the environment in Kenya.  相似文献   
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The Baby‐Friendly Hospital Initiative is a global health promotion intervention that outlines the Ten Steps hospitals should implement to support newborns'' breastfeeding. This US‐based study aimed to determine which hospital characteristics and community factors are associated with hospitals'' attainment of Baby‐Friendly designation. We used a cross‐sectional design and used 2018 data from the Baby‐Friendly, USA Inc. designation program merged with the American Hospital Association annual survey data set. Multilevel logistic regression analysis was used to assess hospital characteristics of interest among the sample consisting of 312 Baby‐Friendly hospitals and 1449 non‐Baby‐Friendly. Our results show that Baby‐Friendly hospitals are more likely to be government nonfederal hospitals, in the Midwest or South regions, serve communities with higher birth totals, and reside in competitive markets. Based on the results of this study, hospitals should seek further and examine their community''s characteristics and structures to identify opportunities and encourage the attainment of improved breastfeeding initiatives such as Baby‐Friendly designation.  相似文献   
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This study investigated the hypoglycemic and antioxidant effects of Flax and Pumpkin seeds mixture on the kidney of alloxan-induced diabetic rats. Animals were allocated into three groups of six rats each: a control group (CD), a diabetic group (DD) and diabetic rats fed with Flax and Pumpkin seeds mixture (DMS) group. The DD rats showed a significant increase of glycemia and lipid parameters such as total lipid, total cholesterol and triglycerides levels compared to those of the control group (CD). In addition, plasma and kidney malonaldialdehyde levels (MDA) were significantly increased compared to (CD) group. Antioxidant enzyme activities such as catalase (CAT), superoxide dismutase (SOD) and non-enzymatic levels of reduced glutathione (GSH) significantly decreased in the plasma and kidney of diabetic rats compared to those of controls. Diet supplemented with Flax and Pumpkin seeds mixture ameliorated the antioxidant enzymes activities observed in diabetic rats and significantly decreased MDA levels. Kidney histological sections, showed glomerular hypertrophy and tubular dilatation. In DMS rats, these histopathological changes were less prominent. Our results suggest that Flax and Pumpkin seeds mixture supplemented in diet of diabetic rats may be helpful to prevent diabetes and its complications.  相似文献   
98.
Pyrethroid pesticides were used preferably over organochlorines and organophosphates due to their high effectiveness, low toxicity to non-target organisms and easy biodegrability. It has widespread applications in agriculture through the world and in Tunisia. The present study investigates lambda-cyhalothrin (LTC) effects on biochemical parameters, hepatotoxicity and their attenuation by vitamin C. Male Wistar rats were randomly divided into three groups of seven each: a control group (C) and two treated groups during 3 weeks with LTC administrated either alone in drinking water for LTC group or coadministred with vitamin C for LTC+vit C group. Lactate deshydrogenase (LDH) activity was significantly increased in liver (+51%, p<0.001) and in plasma (+40%, p<0.001) compared to those of control group. A significant increase of malondialdehyde (MDA) levels in liver (+53%; p<0.001) associated with a decrease in antioxidants enzyme activities and reduced glutathione (GSH) content was observed in LTC group compared to controls. The administration of vitamin C to LTC+vit C group improved all parameters studied.We conclude that LTC induces oxidative stress and modifies biochemical parameters and histological aspects of liver. Administration of vitamin C alleviates the toxicity induced by this synthetic pyrethroid insecticide.  相似文献   
99.
The aim of this study is to investigate the improving effects of selenium (Se) on cerebrum and cerebellum impairments induced by methimazole (MMI) in suckling rats. Animals were randomly divided into four groups of six each: group I served as control which received standard diet; group II received only MMI (250 mg L−1, orally); group III received both MMI (250 mg L−1, orally) and Se (0.5 mg kg−1 of diet); group IV served as a positive control and received Se (0.5 mg kg−1 of diet) as sodium selenite (Na2SeO3). Treatments were started from the 14th day of pregnancy until day 14 after delivery. In the MMI-treated group, plasma-free thyroid hormone levels (FT3 and FT4), protein, DNA and RNA contents in cerebrum and cerebellum decreased when compared to control. Co-treatment with Se ameliorated these parameters. In the MMI-treated group, antioxidant enzyme activities (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) significantly decreased, while malonaldialdehyde (MDA) levels in cerebrum and cerebellum increased. Co-administration of Se through the diet restored these parameters to near normal values. The biochemical modifications are correlated histologically with the abnormal development of an external granular layer, indicating a delay of granular cells migration towards the molecular layer in the MMI-treated group. Our results showed that Se improved cerebrum and cerebellum MMI-induced damages in suckling rats. Moreover, we concluded that Se is an important neuroprotective element that may be used as a dietary supplement against brain impairments.  相似文献   
100.

Aims of the study

The present study was carried out to evaluate the effect of dried mature unripe Morinda citrifolia L. (Rubiaceae) fruit, commonly known as “Noni”, in an aqueous extract preparation (AFE) as used in Thai traditional medicine and its biomarker scopoletin on gastro-esophageal inflammatory models that are related to the claimed pharmacological properties of AFE and/or resembled the human esophagitis or gastric ulcer.

Materials and methods

The powder of dried mature unripe Noni fruit was boiled in water until it became a sticky paste and was then dried into a powder by lyophilization. The pharmacological activity of AFE and pure scopoletin at the same equivalent dose present in AFE was investigated in rat on gastro-esophageal inflammatory models (acid reflux esophagitis, acute gastritis induced by ethanol and serotonin, and chronic gastric ulcer induced by acetic acid); gastric biochemical parameters and gastrointestinal motility.

Results

AFE (0.63-2.50 g/kg) significantly prevented the formation of acid reflux esophagitis, reduced the formation of ethanol-induced acute gastric lesions, suppressed the development of gastric lesions in response to serotonin, and accelerated the healing of acetic acid-induced chronic gastric ulcer in rats with equal potency to those obtained by standard antisecretory agents (ranitidine and lansoprazole). AFE also significantly inhibited gastric acid secretion and pepsin activity in pylorus ligated rats. Additionally, AFE strongly increased the gastrointestinal transit of charcoal meal with a higher potency than cisapride. Pure scopoletin, when compared at the same equivalent dose containing in AFE, possessed similar antiulcer and antisecretory properties to that of AFE although it exerted a less prokinetic activity than AFE.

Conclusion

The findings indicated that AFE as well as its biomarker: scopoletin may be beneficial as a potential preventive and therapeutic agent for gastro-esophageal inflammatory diseases, mainly through its antisecretory and prokinetic activities including an inhibitory activity on serotonin, free radicals, and cytokine-mediated inflammation. Additionally, scopoletin might be one of the biomarker constituents to use for the quality assessment of Noni fruit products used for treating gastro-esophageal inflammatory diseases.  相似文献   
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