Effects of intrapopulation competition on morphological and agronomic characters of Jute plant (Corchorus olitorius L.)

The effects of population density on some agronomic traits of Corchorus olitorius were investigated by growing the seedlings in a field experiment at densities of 1, 2, 5, 10, 25, 50 and 100 plants per m2during the raining season of 2006, at the Ojo campus of Lagos State University (LASU), Nigeria. The randomized block design (RBD) was the experimental design used, with three replicates. The direct effect of competition was investigated on the following agronomic attributes; final height/plant, number of branches/plant, stem girth/plant, number of leaves/plant, total fresh weight, total dry weight, moisture content, total leaf length, leaf petiole length, leaf area, blade length and blade width. A highly significant effect (p < 0.01) of competition was observed for final plant height and total moisture content/ plant, while significant effect (p < 0.05) was observed for other attributes investigated, except for all leaf parameters where insignificant effect of competition was observed. There was a gradual decline in all attributes except height/plant as population density increased. These observations confirmed theoccurrence of intraspecific competition in population of jute plant

Effect of <it>Flabellaria paniculata</it> Cav. extracts on gastric ulcer in rats

<p>Abstract</p> <p>Background</p> <p>The leaves and root of <it>Flabellaria paniculata</it> (Malpighiaceae) are frequently used in the treatment of wounds and ulcers in Nigerian folk medicine. The purpose of this study was to compare the effect of ethanolic extracts from the leaves (FPL) and root (FPR) of <it>F. paniculata</it> on gastric ulcers in rats.</p> <p>Methods</p> <p>The effect of FPL and FPR (100, 200 and 400 mg/kg) was evaluated in ethanol and indomethacin gastric ulcer models. Control groups for FPL and FPR were orally treated with 3% Tween 20 and distilled water respectively. FPL was further investigated in pylorus ligation model. Misoprostol and cimetidine were used as reference.</p> <p>Results</p> <p>FPL significantly (P < 0.05) reduced gastric lesions by 82.22% and 67.32% in ethanol and indomethacin induced ulcer models at 100 mg/kg respectively while FPR (100, 200 and 400 mg/kg) did not exert significant effect in the two models. In pylorus ligation model, FPL exerted a significant preventive antiulcer effect as indicated by reduction in gastric volume at 200 and 400 mg/kg doses. Only 400 mg/kg of the extract exerted a significant reduction in ulcer index when compared with the control group. The oral route LD₅₀ of FPL was estimated to be 4570 mg/kg while that of FPR was 2754 mg/kg. The LD₅₀ in intraperitoneal injection was estimated to be 1202.26 and 1380.38 mg/kg for FPL and FPR respectively. The phytochemical investigation showed that both extracts possess triterpenoids and saponin, while the presence of flavonoid was detected only in FPL.</p> <p>Conclusions</p> <p>The results of this study indicated that FPL and not FPR is effective against experimentally induced gastric ulcers. The presence of varied phytochemical constituents probably influenced the pharmacological differences between the two extracts.</p

A global perspective on the influence of environmental exposures on the nervous system

Economic and social transitions in the era of globalization warrant a fresh look at the neurological risks associated with environmental change. These are driven by industrial expansion, transfer and mobility of goods, climate change and population growth. In these contexts, risk of both infectious and non-infectious diseases are shared across geographical boundaries. In low- and middle-income countries, the risk of environmentally mediated brain disease is augmented several-fold by lack of infrastructure, poor health and safety regulations, and limited measures for environmental protection. Neurological disorders may occur as a result of direct exposure to chemical and/or non-chemical stressors such as ultrafine particulate matters. Individual susceptibilities to exposure-related diseases are modified by genetic, epigenetic and metagenomic factors. The existence of several uniquely exposed populations, including those in the areas surrounding the Niger Delta or north western Amazon oil operations; those working in poorly regulated environments, such as artisanal mining industries; or those, mostly in sub-Saharan Africa, relying on cassava as a staple food, offers invaluable opportunities to advance the current understanding of brain responses to environmental challenges. Increased awareness of the brain disorders that are prevalent in low- and middle-income countries and investments in capacity for further environmental health-related research are positive steps towards improving human health