Lead neurotoxicity has been studied in animal models to induce neurodegeneration. The study was aimed to evaluate the attenuating effects of quercetin on spatial memory impairment and degenerative changes in hippocampus of lead exposed rats. Thirty (30) Wistar rats were randomly divided into six groups of five rats per group (each, n = 5). Groups I (control) and II were administered distilled water and lead, respectively for 42 days. Lead was co-administered with Quercetin and Succimer for Groups III and VI, respectively for 42 days. Groups IV and V were administered lead for 21 days and treated with Quercetin for Group IV and Succimer for Group V for another 21 days. The administration was orally, once per day and lasted for 42 days. Spatial memory was assessed using Eight-arm radial water maze (8-ARWM) test. The rats were anaesthetized with Ketamine at 75 mg/kg intraperitoneally and euthanized. Brain was harvested, processed, Haematoxylin and Eosin stains were used for histo¬logical study of the hippocampus and cells were counted. Results showed spatial memory was impaired and histopatho¬logy such as vacuolation, pyknotic and reduction in pyramidal cells count in CA3 region of hippocampus of lead exposed rats. How¬ever, treat¬ment with quercetin improved spatial memory and histopatho¬logy. Thus, quercetin could be used as an antidote in lead neurotoxicity. Key words: Lead, quercetin, memory, neurodegeneration.
This study aims to screen possible antioxidant potentials of methanol extract and polar fractions of Vernonia calvoana leaves and its phytochemical constituents since the leaves are used ethno medically in managing ailments like wounds, blood pressure, inflammation, arthritis, and bone diseases. Dried leaves (900 g) were ground and de-fatted with n-hexane. The dry marc was extracted using 80% methanol and water. Filtrate was concentrated using rotary evaporator at 40°C. Acute toxicity study and phytochemical analysis were performed with crude extract. Fractionation of crude extract using gradient concentrations of methanol and distilled water yielded 4 fractions - F1, F2, F3 and F4. Fractions with the crude were used for in vitro antioxidant studies. From the results, crude extract showed no signs of toxicity in mice at 2000 mg/kg orally. Phytochemical screening showed presence of alkaloids, flavonoids, tannins, phenols, steroids, saponins, terpenes, arthroquinones, carbohydrates and glycosides. The highest percentage antioxidant activity observed with crude extract was 72.37 at 500 µg/ml in DPPH spectrophotometric assay. DPPH results showed percentage antioxidant activity of 81.4% at 500 µg/ml of F1 and 67.73% at 500 µg/ml of F2. The FRAP values of the crude extract, F1, F2, F3 and F4 at 500 µg/ml were 1.957, 2.234, 1.731, 1.245 and 1.025 µM respectively. These results showed that the activities of methanol extract of leaves of V. calvoana may be dependent on the concentration of the extracting solvent. Vernonia species are known to contain abundant saponins and flavonoids which are polar compounds and readily soluble in methanol. This may explain the above observed antioxidant activities and thus, the use of the leaves in different traditional curative therapies in Southern Nigeria. Key words: Vernonia calvoana, leaves, antioxidants, crude extract, phytochemicals.
The present study was aimed at investigating the effect of Cannabis sativa L. administration on neurobehavior and histology of the frontal cortex ofadult Wistar rats. Eighteen (18) adult Wistar rats (120 to 140 g) were divided into three (3) groups of six (6) animals per. Animals in group 1 (control) were given 1 ml/kg distilled water, while groups 2 and 3 were administered with 250 and 500 mg/kg of n-Butanol extract of Cannabis sativa L. respectively via the oral route, daily for 21 days. Motor function was assessed using Ladder rung walking while Haematoxylin and Eosin (H&E) and Cresyl Fast Violet (CFV) stains were used for histological studies of the cerebral cortex. A treatment of rats with 250 and 500 mg/kg showed decrease in foot fault scoring in group 2, and 3 when compared with the control. Also, cytoplasmic vacuolation, dissolution of nucleolus were observed in 250 and 500 mg/kg treatment groups when stained with Haematoxylin and Eosin (H&E) and chromatolysis was observed in 250 mg/kg and 500 mg/kg treatment group. It was concluded that Cannabis sativa L. administration results in motor impairment which could be due to degenerative changes in the cerebral cortex of adults Wistar rats. Key words: Cannabis sativa L., n-butanol, cerebral cortex, Wistar rats, ladder rung walking.
The increasing trends of insect associated bacterial infection in humans are severely hampered by disparaging number of bacteria obtained with the culture-based technique. This study therefore determined how the analysis of the 16S rDNA sequences would compare in terms of precision and reliability to the most adoptable culture-based technique. Results obtained depict enhanced accuracy of molecular technique over the cultural method as only 249 (69%) of the total isolates were correctly identified by the cultural method to represent a total of 114 (31%) discrepant species while 100% correct identification was observed with the molecular technique. The most predominant of these bacterial isolates from both the external surfaces and the gut environment was Escherichia coli 43 (20.8%) and 24 (15.5%) respectively. The Gram positive organisms isolated were Staphylococcus aureus, Bacillus subtilis, Staphylococcus epidermidis, and Enterococcus faecalis with a prevalence rate of 8 (3.8%), 14 (6.7%), 8 (3.8%) and 9 (4.3%) from external surfaces and 2 (1.3%), 6 (3.9%), 2 (1.3%) and 7 (4.5%) from gut environment respectively. The least isolated organisms in the external surfaces were Serratia marscencens and Citrobacter werkmanii with a distribution rate of 3(1.4%) while Citrobacter freundii 2(1.3%) was the least isolated organism from cockroach gut environment. This study therefore showed that the molecular analysis of the 16S rDNA sequences is more efficient than culture-based technique for the identification of bacterial contaminants of cockroaches because occurrences of misidentification are very much abated by this method. Key words: Bacterial contaminants, Cockroaches (Periplaneta americana), cultural technique, molecular technique.
