Statistical Methods in Medical Research.

The investigation of anti-plasmodia effect of metabolic leaf extract of Gyssypium barbadense in P. Berghei (NK 65 Chloroquine resistance strain) infected Swiss albino mice. The animals were grouped into six (I, ii, iii, iv, v, vi) of five (5) mice each. Group (i) given 50mg/kg dosage of the leaf extract, Group ii 100mg/kg Group iii 200/kg, Group iv given anti-malaria drug (ACT A) at a DOSE OF 3.81MG/KD, Group v given coartem and Group vi served as a -ve control. A four days curative test was carried out. The % parasite inhibition of the leaf extract at 50mg/kg is 58.29% at 100mg/kg is 61.16 % at 200mg/kg is 51.92% and 41.60% for group (iv) & 66.23% for group (v). The % parasite density was observed to increase with increase in concentration of the leaf extract (50<100<200). The progression in %parasite inhibition by the leaf extract as compared with +ve control group (IV) & (v) of a purified drug has better efficacy, it is premature to conclude. The leaf extract was found to contain Flavonoids, Sappnnin, Cardiac glycosides, PHENOL. It is observed in the result a significant increase (p<0.05) in weight of the animals on treatment with the leaf may contain antiplasmodia agents.

Combating MALARIA in Sub-Saharan Africa - The Potential of Local Plant

Background: Pain being one of the many symptoms experienced in the course of an infection, this study was designed to investigate antinociceptive activity of two medicinal plants used to treat malaria traditionally. In traditional health practice there is usually a misunderstanding on whether the plants clear the disease causing organism or they cure the pain as one of the most common symptoms. The plants were selected based on their ethnomedical literature as a means of establishing a distinction between their antinociceptive and bio-activities. Objective: To determine antinociceptive effect of Pentas lanceolata and Ximenia americana. Materials and Methods: The aerial parts of P. lanceolata and the stem bark of X. americana were collected from Kiangombe forest and Kerio Valley in Embu and Elgeyo Marakwet Counties respectively. The collection was done with the help of an experienced taxonomist. The plant parts were dried, and extracted with methanol and aqueous solvents. Analgesic activity was determined by the tailflick and formalin test techniques in male albino mice. The positive control used in the experiment was acetylsalicylic acid (ASA) at 100 mg/kg. Results: Antinociceptive activity of the plant extracts in the tail flick assay was time and dose dependent, except in the case of P. lanceolata methanol extract. In the formalin test, the extracts significantly (p<0.05) reduced the time spent in pain behavior in both the early and late phases Conclusion: The results of this study support the use of these plants to manage pain and imply other pharmacological benefits to the host other than parasiticidal effect in malaria treatment. Keywords: Medicinal plants, tail-flick, formalin test, antinociceptive

Antinociceptive effect of Pentas lanceolata and Ximenia americana medicinal plants used to treat malaria traditionally in Kenya

Background: Resistance development to antimalarial drugs necessitates the look at traditional medicinal plants as sources of novel compounds that could have the otential to be developed into new antimalarial therapies. Four medicinal plants used in Kenya to treat malaria were investigated. Objective: To determine the in vitro and in vivo antimalarial activity and safety of four medicinal plants used in Kenya to treat malaria. Materials and Methods: Ximenia americana, Sericocomopsis hilderbrandtii, Pentas lanceolata and Fuerstia africana were collected from their habitat, dried, and extracted with methanol and aqueous solvents. In vitro antiplasmodial activity carried out using Plasmodium falciparum, In vivo antimalarial activity using Plasmodium berghei ANKA strain in Swiss albino mice. Cytotoxicity was carried out using MTT assay on VeroE99 cell lines, acute toxicity was investigated in Swiss albino mice. Results: All extracts had good in vitro activity against D6 strain of Plasmodium falciparum with IC 50 30% while three demonstrated low activity. Fuerstia africana was moderately cytotoxic. Except for Ximenia americana water extract, all the extracts were safe with LD 50 > 5000mg/Kg. Conclusion: Results of this study support medicinal use of these plants and indicate that useful compounds can be isolated for further exploitation, formulation and use. Keywords: Medicinal plants, antiplasmodial activity, cytotoxicity, acute toxicity

Charles K Rotich

Papers

Antimalarial activities and toxicity levels of selected medicinal plants used in Kenya