Is there a suburban sleeping sickness in Libreville?

BACKGROUND: The transmission of sleeping sickness occurs primarily in rural areas, and exposed populations are those living from rural activities such as agriculture, fishing, animal husbandry or hunting. However, urban and suburban foci are more and more reported in T. b. gambiense areas. In Libreville town, sleeping sickness cases are regularly diagnosed. In order to investigate about the establishment of a transmission cycle of that disease, we have carried out an entomological survey in two quarters in the vicinity of the town. METHODS: Vavoua traps were set out in all suitable biotopes for tsetse flies during four days and examined twice a day. Flies were collected, identified and dissected. RESULTS: Two species of Glossina were caught: G. palpalis palpalis (90.58%) and G. caliginea (9.42%). A total infection rate of 9.37% was observed after dissection of all non-teneral flies captured. CONCLUSION: These results suggest the establishment of a trypanosomiasis transmission cycle in the area. No salivary gland was found infected. Given that infected persons are regularly detected, we can think about the existence of a suburban sleeping sickness focus in Libreville. More analysis is needed concerning the identification of human trypanosomes and the origin of Glossina blood meals that may confirm the existence of that focus.

Analgesic and anti-inflammatory effects of Cassia siamea Lam. stem bark extracts.

AIM OF THE STUDY: The present study was carried out to investigate analgesic and anti-inflammatory activities of Cassia siamea Lam stem bark extracts. We have also determined the cytotoxicity of each extract. MATERIALS AND METHODS: C. siamea, a widespread medicinal plant traditionally used in sub-Saharan Africa, was collected in Congo Brazzaville. Stem bark was extracted with petroleum ether (CSE1), chloroform (CSE2), ethanol (CSE3) and water (CSE4). Analgesic, anti-inflammatory and antipyretic activities of these extracts were assessed in rats with hot plate test, paw pressure and carrageenan induced paw oedema. Cytotoxicity was assessed against KB and Vero cells. RESULTS: At the doses used (100, 200, and 400mg/kg) ethanol and water extracts showed significant and dose-dependent analgesic and anti-inflammatory effects. None of the extracts had cytotoxic activity on KB and Vero cell lines and the most active extracts (CSE3 and CSE4) had no acute toxicity. CONCLUSIONS: The study highlighted the analgesic and anti-inflammatory of C. siamea stem bark. Four major families of compounds present in the plant may explain these activities: triterpenes (lupeol, oleanolic acid, ursolic acid, friedelin, betulin), flavonoids (apigenin, kaempferol, luteolin), anthraquinones (emodin), phytosterols (stigmasterol, beta-sitosterol).

In vitro antiplasmodial activity of 18 plants used in Congo Brazzaville traditional medicine.

Sixty-six extracts of 18 plants commonly used by traditional healers in Congo Brazzaville for the treatment of malaria have been investigated for in vitro antiplasmodial activity. Ethanolic and dichloromethane extracts of 7 among the 18 studied plants were moderately active (10 microg/ml

Corneal penetration and metabolism of the antiherpetic 5-iodo-2'-deoxycytidine.

The study of the permeability of the cornea to 5-iodo-2'-deoxycytidine (IDC), an antiherpetic agent was performed in the rabbit. In a first experiment, using 125I-IDC eye-drops and a sustained contact between the drug and the cornea, we showed that the penetration of IDC in the aqueous humor was important. In a second experiment, using a HPLC method, we studied comparative ocular penetration and metabolism of IDC and 5-iodo-2'-deoxyuridine (IDU).