TReND in Africa: Toward a Truly Global (Neuro)science Community.

TReND is a volunteer-scientist run charity dedicated to promoting research and education on the African continent. Focusing on neuroscience, we discuss approaches to address some of the factors that currently stifle Africa's scientific development and our experience in implementing them.

Bridging the Gap: establishing the necessary infrastructure and knowledge for teaching and research in neuroscience in Africa.

Advances in neuroscience research over the last few decades have increased our understanding of how individual neurons acquire their specific properties and assemble into complex circuits, and how these circuits are affected in disease. One of the important motives driving neuroscience research is the development of new scientific techniques and interdisciplinary cooperation. Compared to developed countries, many countries on the African continent are confronted with poor facilities, lack of funding or career development programs for neuroscientists, all of which deter young scientists from taking up neuroscience as a career choice. This article highlights some steps that are being taken to promote neuroscience education and research in Africa.

Evaluation of five medicinal plants used in diarrhoea treatment in Nigeria.

Five medicinal plants [Acacia nilotica, Acanthospermun hispidum, Gmelina arborea, Parkia biglobosa and Vitex doniana] used in diarrhoeal treatment in Kaduna State, Nigeria, were investigated. This study was carried out on perfused isolated rabbit jejunum and castor oil-induced diarrhoea in mice. The aqueous methanol extracts (0.5, 1.0, 2.0 and 3.0 mg/ml) were generally found to cause a dose-dependent response in the isolated rabbit jejunum, though this was not uniform in all the plants. Gmelina arborea and Vitex doniana showed concentration dependent relaxation at low doses (0.5, 1.0 mg/ml), but showed no significant relaxation at higher doses (2.0, 3.0 mg/ml). Other extracts showed biphasic effects. For example, Acacia nilotica at 3.0 mg/ml caused initial relaxation quickly followed by contraction. In the castor oil-induced diarrhoeal, 100% protections were shown by extracts of Acacia nilotica and Parkia biglobosa (100, 200 mg/kg) while Vitex doniana showed a dose-dependent effect. The least protection was shown by Acanthospermun hispidum, at the same dose, when compared with the other four plants. The results obtained revealed that the aqueous methanol extracts of all the five medicinal plants investigated have pharmacological activity against diarrhoea. This may explain their use in traditional medicine for the treatment of diarrhoea.

Analgesic activity of the roots and leaves extracts of Calliandra portoricensis.

The analgesic activity of the methanolic extracts of the roots and leaves of Calliandra portoricensis was investigated in mice and rats using acetic acid-induced writhing and formalin tests. The extracts given orally at the doses of 200, 400, 600 mg/kg showed a dose-dependent activity in the tests used.

Correlation of gastric mucosal damage with sialic acid profile in rats: effect of hydrochloric acid, pepsin and hypertonic saline.

Sialic acids occupy terminal positions on gastric mucus glycoprotein where they contribute to the high viscosity of mucin. Desialylation of mucus may lead to degradation of the mucus and eventually to the breakdown of the gastric mucus barrier. The effect of a variety of damaging agents (0.1 M HCl, 2 mg ml(-1) pepsin and 2 M NaCl) on sialic acid profile was determined in pylorus-ligated rats. The relationship between sialic acid, galactose, pyruvate and the extent of gastric mucosal damage were studied. Instillation of pepsin significantly increased total sialic acid, galactose and macroscopic mucosal lesions in the stomach. Instillation of 0.1 M HCl reduced the total sialic acid but this decrease was not significant. Acidity led to a significant increase in the amount of free sialic acid in the gastric instillates and the macroscopic lesions induced by acid was not significantly different from the control animals (0.15 M NaCl). 2 M NaCl induced the macroscopic lesions in the stomach and also free sialic acid in the instillates. Pepsin potentiates the action of 2 M NaCl. In all the agents examined with the exception of acid, it was observed that an increase in free sialic acid and galactose was accompanied by gastric mucosal erosion and elevation of pyruvate concentration. It is concluded that gastric acidity alone is not inherently damaging and that resistance of gastric mucosa to destructive agents may be dependent on the integrity of the sialic acids.

The effect of Aloe vera A. Berger (Liliaceae) on gastric acid secretion and acute gastric mucosal injury in rats.

The effect of varying doses of ethanol extract of Aloe vera (Liliaceae) on acute gastric mucosal lesions induced by 0.6 M HCl and acid output was studied in the pylorus ligated and lumen perfuse rats, respectively. Acid secretion was determined by titration of the collected gastric juice to pH 7.0. Intraperitoneal injection of Aloe vera, dose dependently inhibited gastric acid secretion. The plant was more active as a gastroprotective agent at lower concentration against mucosal injury induced by 0.6 M HCl. In conclusion, Aloe vera is endowed with gastric acid anti-secretory activity and could protect the gastric mucosa at low concentrations against injurious agents.