Residual risk of HIV, HVB and HCV transmission by blood transfusion between 2002 and 2004 at the Abidjan National Blood Transfusion Center.

The assessment of the viral residual risk from blood products is an assessment indicator of the quality management system and of the availability process of these products. Assessments of HIV, HBV and HCV viruses transmission risks through blood transfusion are calculated after the setting of a quality approach at the Abidjan NBTC. The method used estimates the risk of a donation made during a period immunologically silent. The residual risks for HIV, HBV, and HCV viruses have been estimated by multiplying the incidence rate for 100,000 people per year by the respective durations of the serological windows. The data received from the Abidjan Center's information processing system (Progesa 4.4d of MAK SYSTEM) go from 2002 to 2004 period. The residual risks are 1/5780 donations for HIV and 1/406 donations for the HCV, then 1/383 donations for the HBV. The residual risk for the HIV is almost four times reduced compared to that of 1997. The results show not only the importance of the transmission risk of HIV, HBV and HCV viruses through blood products, but also the necessity to set a quality management system in endemic countries of Sub-Saharan Africa.

Leaf extract of Caesalpinia bonduc Roxb. (Caesalpiniaceae) induces an increase of contractile force in rat skeletal muscle in situ.

The pharmacological properties of Caesalpinia bonduc Roxb. (Caesalpiniaceae) are not well known, but it is used traditionally to treat snake bite (Bellomaria and Kacou, 1995; Schaffner, 1997). In the present study, the mechanism through which Caesalpinia bonduc extract (Cebo) affects gallamine-induced relaxation in rat tibial muscle contractility were studied via measurement of isometric-tension-anesthetized, 10-12-week-old, male rats. Isometric twitch contractions of the indirectly-stimulated anterior tibia muscle of the right hindleg were recorded in situ. Cebo administered intravenously (i.v.) increased twitch contractions in a dose-dependent manner. The ED50 value is 2.75 x 10(-4) g/kg body wt. Similar results were obtained using the anticholinesterase neostigmine. In contrast, gallamine (a non-depolarizing muscle relaxant) or the venom of the puff adder Bitis arietans reduced the force of contraction. Treatment with Cebo or neostigmine, however, reversed the relaxation induced by either gallamine or puff adder venom. In conclusion, Cebo stimulates the muscle contractile activity, an effect which may be due to an activation of the cholinergic mechanism.

Effects of leaf extract of Caesalpinia bonduc (Caesalpiniaceae) on the contractile activity of uterine smooth muscle of pregnant rats.

The calcium dependency and the cholinergic effect of the leaf extract of Caesalpinia bonduc Roxb. (Caesalpiniaceae) was studied in isolated pregnant rat myometrium preparations. Isometric contractions were recorded. The extract (Cebo) increased the contractile force in the isolated strips in a concentration-dependent manner. The effects were comparable to those obtained with acetylcholine. Contractions induced by Cebo or acetylcholine were inhibited in the presence of atropine. The stimulating action of Cebo on the contractile responses of isolated myometrium preparations inhibited by atropine may be mediated by cholinergic receptors. In calcium-free solution Cebo induced a tonic contraction (contracture) of the muscle. Moreover, in high-potassium calcium-free solution Cebo caused contracture of the uterine smooth muscle. Cebo was still able to elicit contractions in calcium-free solution containing EDTA or EGTA. These findings suggest the existence of cholinergic receptors sensitive to Cebo which could influence the influx of calcium (phasic contraction) and mobilization of calcium from cellular stores (tonic contraction), both of which are responsible for the increase of contractile activity and development of the contracture of uterine smooth muscle.

Uterotonic effects of hydromethanolic extract of Parquetina nigrescens (Periplocaceae) on spontaneous contractile activity in the isolated myometrium of pregnant rats.

Parquetina nigrescens (Afz.) Bullock (Periplocaceae) hydromethanolic extract (PAR) in reference solution exerts a stimulating and spasmogenic action on the pregnant rat myometrium in vitro. This action is characterised by increasing amplitude of spontaneous isometric contractions and a slight elevation of muscular basic tonus. These effects on myometrium may be compared with those provoked by sulprostone (PGE2) in the same experimental conditions. In calcium free solution, Parquetina nigrescens extract could restore partially spontaneous contractile activity. On the contrary, in presence of EDTA PAR induces a complete abolition of the activity. On the other hand, in calcium free solution, sulprostone is able to develop a clear elevation of basic tonus (contracture). These observations support the hypothesis that the extract has an oxytocin-like effect, which is characterised by an extracellular influx of calcium, responsible for the increase of the maximum isometric contraction amplitude. Sulprostone activates both extracellular and intracellular calcium responsible for the increase of contractile activity and development of the contracture of uterine smooth muscle.