Mitogenic activities in African traditional herbal medicines (Part II).

Mitogenic activities in African traditional herbal medicines were examined on human peripheral blood lymphocytes and mouse spleen cells using protein fractions obtained from their extracts by precipitation with ammonium sulfate. Target specificity for these mitogens was investigated by using isolated T cells and lymphocytes from athymic nude mice. Among 20 plants investigated, potent mitogenic activities for both human and mouse lymphocytes were found in 7 plants: Monanthotaxis sp. (Annonaceae), Uvaria lucida (Annonaceae), Maytenus buchananii (Celastraceae), Lonchocarpus bussei (Leguminosae), Phytolacca dodecandra (Phytolaccaceae), Phytolacca octandra (Phytolaccaceae), and Toddalia asiatica (Rutaceae). The U. lucida stem demonstrated the highest activity among all and induced mitogenesis both in human and mouse isolated T cells, but not in lymphocytes from athymic nude mice.

Cardiovascular risk factor profiles in mild to moderate hypertensives seen at Kenyatta National Hospital.

Sixty newly diagnosed adult patients with mild to moderate essential hypertension were assessed to determine their cardiovascular risk factor profiles. Detailed history and physical examinations were done. Resting 12-lead ECG was done and serum levels of uric acid, fasting cholesterol, and fasting glucose were determined. Twenty nine patients had hypertension and two or more cardiovascular risk factors. The most prevalent cardiovascular risk factors other than hypertension were electro-cardiovascular left ventricular hypertrophy (31.7%), obesity (28.3%) and hypercholesterolaemia (28.3%). About a half of these patients (48.3%) can be classified as high risk hypertensives. This calls for aggressive management of cardiovascular risk factors as a whole and not just hypertension alone if we are to reduce incidence of hypertensive complications.

Mitogenic activities in African traditional herbal medicines.

Mitogenic activities in African traditional herbal medicines were examined using protein fractions obtained from their extracts by precipitation with ammonium sulfate. Potent mitogenic activities for human and mouse lymphocytes were found in the three plants: Croton macrostachyus, Croton megalocarpus (Euphorbiaceae), and Phytolacca dodecandra (Phytolaccaceae). All the gel chromatographic patterns of these protein fractions progressed toward the smaller molecule site with pronase treatment, while their mitogenic activities decreased significantly. Protein fractions from these three plants induced mitogenesis both in human and mouse isolated T cells, but not in lymphocytes from athymic nude mice. By testing further fractionated protein fractions with gel filtration chromatography, it was found that all three plants contained several mitogens having different molecule sizes.

Acetylation status using hydralazine in African hypertensives at Kenyatta National Hospital.

In this study, the investigation of hydralazine acetylator phenotype was undertaken for the first time in African hypertensives at Kenyatta National Hospital. A total of 25 randomly selected patients with moderate to severe hypertension (diastolic pressure 105-130 mmHg), participated in the phenotyping study. The phenotyping was done by administering oral standard hydralazine dose of 150 mg/day in three divided doses. The 24 hour urinary MTP/hydralazine ratio was used to categorize patients into slow and fast acetylators. Of the patients studied 69.9% were slow acetylators while 30.4% were fast acetylators. The mean 24 hour urinary MTP/hydralazine ratio for slow acetylators was 1.01 +/- 0.95. This was significantly different from the fast acetylators where the mean 24 hour urinary MTP/hydralazine ratio was 10.6 +/- 4.4 (P < 0.001). The acetylator phenotyping divided the patients into two distinct populations and no further arbitrary method was required to divide the patients into either group.

A comparative study of the neutralising capacity of eight brands of antacids.

Eight brands of antacid tablets commonly available in the private market in Kenya were subjected to in-vitro tests for neutralizing capacity. The neutralizing capacity per gram and per tablet of the products was compared. The neutralizing capacity in millilitres of 0.1 M HC1 per gram ranged from 103.10 for Gelusil to 225.13 for Maalox, with others ranging between +/- 18.1% and -12% about the average. The neutralizing capacity per tablet ranged from 64.90 ml for Magnesium trisilicate Co tablets B.P. to 263.15 ml for Maalox, with the others ranging between +/- 24.9% and -33.1% about the average. This shows high variation in the neutralizing capacities of the different brands available especially in relations to the neutralizing capacities per tablet due to the high variation in the tablet weight.

Mefloquine disposition in normals and in patients with severe Plasmodium falciparum malaria.

Mefloquine pharmacokinetics were studied in Kenyan African normal volunteers and in patients with severe acute attack of Plasmodium falciparum malaria. Peak concentrations were achieved in both groups at 20-24 hours. The mean half-life of elimination was 385 +/- 150 hours (mean +/- SD) in normal subjects while in severe malaria it was 493 +/- 215 hours which was significantly longer (P less than or equal to 0.001). The volume of distribution was significantly smaller in severe malaria where it was 30.76 +/- 10.50 l/kg (mean +/- SD) while in the normal subjects it was 40.90 +/- 20.70 l/kg (mean +/- SD) (P less than or equal to 0.001). The total body clearance in severe malaria was 3.75 +/- 1.51 l/h (mean +/- SD). This was significantly lower than in the normal subjects where it was 5.15 +/- 1.50 l/h (mean +/- SD) (P less than or equal to 0.001).

Disposition of antipyrine in African patients with Hodgkin's lymphoma.

The pharmacokinetics of antipyrine were studied in 12 healthy volunteers and 10 patients of Kenya African origin with Hodgkin's lymphoma. The half-life of antipyrine was 12.2 +/- 1.3 h (mean + s.d.), while the apparent volume of distribution (V) was 0.67 +/- 0.11 l kg-1 (mean +/- s.d.) and the total body clearance was 40.7 +/- 3.2 ml kg-1 h-1 (mean +/- s.d.) in the healthy volunteers. The antipyrine half-life in the patients with advanced Hodgkin's lymphoma was 17.1 +/- 2.7 h (mean +/- s.d.). The apparent volume of distribution was 0.72 +/- 0.14 l kg-1 (mean +/- s.d.) which was larger than in healthy volunteers (P less than 0.05). The total body clearance was 30.3 +/- 9.4 ml kg-1 h-1 (mean + s.d.) and this was reduced compared with that in healthy volunteers (P less than 0.02). After cytotoxic therapy the half-life in the patients with advanced Hodgkin's lymphoma was significantly decreased to 8.3 +/- 1.3 h (mean +/- s.d.) (P less than 0.07), and the apparent volume of distribution was reduced to 0.65 +/- 0.07 l kg-1 (mean +/- s.d.) (P less than 0.05) while the total body clearance increased to 52.8 +/- 5.5 ml kg-1 h-1 (mean +/- s.d.) (P less than 0.01).