N Nyazema

Ministry of Health and Child Welfare, Zimbabwe, Salisbury, Harare Province, Zimbabwe

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Publications (20)27.99 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Abstract The Doctrine of Signatures or Similitudes simply states that “like cures like” and each medicinal product from nature indicates by an obvious and well-marked character the disease for which it is a remedy or the object for which it can be employed. The Doctrine exerted influence in Europe until late in the 17th century and still does so in most parts of Africa including Zimbabwe. Medicinal plants found, from interviewing traditional healers, to be commonly used for the treatment of Schistosoma haematobium, most of which produce either red seeds, red sap or red extract, were collected and investigated for their anti-schistosoma activities. The plant materials were prepared according to the guidelines of the traditional healers and their efficacy was determined by administering the crude extracts to laboratory animals infected with S. haematobium. The results suggested that plant extracts from Abrus precatorius L., Pterocarpus angolensis DC. and Ozoroa insignis Del. complied with the apparent signatures.
    09/2008; 32(2):142-148.
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    ABSTRACT: To identify predictors and define reference values for T lymphocyte subsets in HIV negative pregnant black women. Cross sectional study. Edith Opperman Martenity Hospital, Harare, Zimbabwe. 1113 HIV negative women 22 to 35 weeks pregnant registering for routine antenatal care. A questionnaire was used to collect demographic and obstetric data. CD4 and CD8 T lymphocyte counts were determined by manual immunocytochemistry. Concentrations in serum, of retinol, beta-carotene, ferritin, folate and 1-antichymotrypsin were also measured. Multiple linear regression analysis was employed to identify and estimate effects of potential predictors. CD4 and CD8 T lymphocyte levels, demographic, obstetric data and micronutrient status. Predictors of CD4 counts were gestational age, serum retinol and season. CD4 counts declined by 25 (95% confidence interval [CI]; 11 to 40; p = 0.001) cells/L for each week's increase in gestation among women with low serum retinol, while low serum retinol was independently associated with lower CD4 counts (-127; 95% CI, -233 to 20 cells/L; p = 0.02) at 35 weeks gestation. The late rainy season was associated with higher CD4 counts (137; 95% CI, 67 to 207 cells/L; p < 0.001). CD8 counts were higher in women with low serum folate (87; 95% CI, 6 to 166 cells/L; p = 0.036) and were slightly higher in gravida 4+ compared to gravida one to three. Reference values of CD4 but not CD8 count and percentage markedly differed from flow cytometry values of pregnant and non-pregnant women in developed and developing countries reported in the literature, even after controlling for the differences in methods of T lymphocyte subset immunophenotyping. Gestational age, gravidity, micronutrient status and season influence T lymphocyte subset levels and need to be considered when designing clinical management and intervention strategies for pregnant women. The data underscores the need for local reference values.
    The Central African journal of medicine 01/2004; 50(1-2):10-9.
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    ABSTRACT: Excessive accumulation of fat in women of childbearing age is a concern, since obesity is an important cause of morbidity and mortality. Deposition of fat during pregnancy, which is not metabolized during lactation, may contribute. However, the individual effects of age and gravidity on fat accumulation have not been disentangled. Based on multiple linear regression analysis of anthropometric data from 1113 pregnant women from Zimbabwe, we found evidence to suggest that fat deposition is an effect of age rather than gravidity that is precipitated by the first pregnancy.
    International Journal of Obesity 10/2002; 26(9):1274-6. · 5.22 Impact Factor
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    ABSTRACT: Folate and iron status and hemoglobin concentrations are important to maternal and infant health. Our goal was to identify predictors of serum folate, serum ferritin, and hemoglobin. This was a cross-sectional study of 1669 pregnant women (22-35 wk of gestation) in Harare, Zimbabwe, who were receiving prenatal care. The statistical effects of age, season, gestational age, gravidity, HIV-1 infection, malaria parasitemia, and serum alpha1-antichymotrypsin (ACT) on serum folate, serum ferritin (log10 transformed), and hemoglobin were estimated by using multiple linear regression analyses. Serum folate (x: 11.4 micromol/L) was 0.52-nmol/L (95% CI: 0.04, 1.0) lower in HIV-infected women than in uninfected women and 0.65-nmol/L (0.014, 1.28) lower in weeks 25-35 than in weeks 22-25. Serum ferritin (geometric x: 11.6 microg/L) was 0.93 times (0.86, 0.99) lower in HIV-infected women and 2.25 times (1.41, 3.61) higher in women with malaria parasitemia than in uninfected women. Similarly, serum ferritin was 0.71 times (0.63, 0.79) higher in weeks 32-35 than in weeks 22-25 and 1.21 times (1.12, 1.29) higher in gravida > or =3 than in gravida 1. Elevated serum ACT was a strong predictor of serum folate, serum ferritin, and hemoglobin. HIV infection was associated with a 12.9-g/L (8.9, 16.8) lower hemoglobin concentration in women with nondepleted iron stores but low serum retinol and a 7-8-g/L lower hemoglobin concentration in women with other combinations of serum ferritin and retinol (P for interaction = 0.038). Season, age, gestational age, and gravidity were not significant predictors of hemoglobin. Low serum folate, ferritin, and retinol were associated with low hemoglobin. HIV was associated with lower serum folate, serum ferritin, and hemoglobin. HIV infection was also associated with lower hemoglobin, particularly in women with stored iron and low serum retinol. Low serum folate, ferritin, and retinol were associated with low hemoglobin.
    American Journal of Clinical Nutrition 06/2001; 73(6):1066-73. · 6.50 Impact Factor
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    ABSTRACT: Vitamin A status during pregnancy is important to maternal and infant health. Our goal was to identify predictors of serum beta-carotene and retinol. This was a cross-sectional study of 1669 women (22-35 wk of gestation) in Harare, Zimbabwe, who were receiving prenatal care. The statistical effects of age, season, gestational age, gravidity, HIV-1 infection, malaria parasitemia, and serum alpha1-antichymotrypsin (ACT) on serum beta-carotene (log10 transformed) and retinol were estimated by using multiple linear regression analyses. HIV infection was found in 31.5% of the women; 0.4% had malaria. Serum beta-carotene concentrations (geometric x: 0.19 micromol/L) were lower in HIV-infected women than in uninfected women (10beta = 0.78; 95% CI: 0.72, 0.84) and increased with age (10beta = 1.05; 1.02, 1.07) in gravida 1 but not in gravida > or =2 (P for interaction = 0.00002). Serum retinol (x: 0.92 micromol/L) increased with age (beta = 0.004; 0.0001, 0.008) in uninfected women but not in HIV-infected women (P for interaction = 0.02) and was 0.05-micromol/L (0.02, 0.09) lower in HIV-infected women than in uninfected women at 24 y of age. Furthermore, gestational age, season, use of prenatal supplements, and malaria were predictors of serum beta-carotene. Serum retinol was lower in women carrying male (beta = -0.04; -0.08, -0.00005) and multiple (beta = -0.21; -0.35, -0.08) fetuses. Serum ACT concentrations of 0.3-0.4, 0.4-0.5, and >0.5 g/L were associated with 3%, 11%, and 44% lower serum beta-carotene and 0.04-, 0.15-, and 0.41-micromol/L lower serum retinol. Serum ACT (g/L) was higher in women with malaria than in those without (beta = 0.10; 0.03, 0.16) and in gravida 1 than in gravida > or =2 (beta = 0.012; 0.003, 0.021), but was not higher in HIV-infected women than in uninfected women (beta = 0.001; -0.008, 0.011). HIV infection, malaria, gravidity, and gestational age were predictors of serum beta-carotene and retinol. Serum ACT was an important predictor of both and was associated with gravidity and gestational age.
    American Journal of Clinical Nutrition 06/2001; 73(6):1058-65. · 6.50 Impact Factor
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    ABSTRACT: To enumerate CD4 and CD8 T-cells using the simple and cheap immuno-alkaline phosphatase (IA) method and to compare it with flow cytometry (FC); and to study the effects of duration of sample storage on the IA method results. Method comparison study. Blair Research Laboratory, Harare, Zimbabwe. 41 HIV positive and 11 HIV negative men and women from Harare participating in HIV studies at Blair Research Laboratory, Zimbabwe. CD4 and CD8 T-cell counts by FC and the IA method. The IA method and FC were highly correlated for CD4 counts (Spearman rs = 0.91), CD4 percentage (rs = 0.84), CD8 count (rs = 0.83), CD8 percentage (rs = 0.96) and CD4/CD8 ratio (rs = 0.89). However, CD4 cell counts and percentage measured by the IA method were (mean difference +/- SE) 133 +/- 24 cells/microL [corrected] and 6.7 +/- 1.1% higher than those measured by the FC method (p < 0.0001) respectively. CD8 counts and percentages by the IA method were lower than those by the FC method (p < 0.01). Accordingly, the IA method gave a higher CD4/CD8 ratio (p < 0.01). IA method CD4 counts < 300/mL best predicted FC CD4 counts < 200/mL while IA CD4% < 25 best predicted FC CD4% < 14%. IA method CD4/CD8 ratio < 0.8 best predicted FC CD4/CD8 ratio < 0.5. Smears stored for up to 18 months gave results similar to fresh smears. The IA method correlates well with but gives CD4 counts and percentages that are higher than those determined by FC. On the contrary, the IA method gives CD8 counts and percentage that are lower than FC values. The method is a cheap and reliable alternative to FC and allows storage of samples for extended periods before analysis, making it an appropriate technology for resource poor countries.
    The Central African journal of medicine 03/2001; 47(3):64-70.
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    K Bhagat, N Nyazema
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    ABSTRACT: To assess the attitudes of general practitioners in Harare, Zimbabwe, towards the use of clinical practice guidelines (CPG's). Cross sectional survey. General practitioners in private practice within the urban Harare (Zimbabwe) environs. Two hundred and thirty two general practitioners in Harare, Zimbabwe. The response to a questionnaire enlisting attitudes to CPGs. Questionnaires were sent to 232 general practitioners. Of these, 137 (59.1%) returned a completed questionnaire. Among the respondents, 95.6% felt that general practitioners should be involved in the development of guidelines, 72.6% had read at least one guideline, 65.9% were prepared to use guidelines in their practice, 61.6% thought that guidelines would improve their treatment ability, and 59.7% thought that guidelines would improve their knowledge of disease. 76.5% felt that the government should not legislate, 66.2% felt that guidelines reduce practitioners' flexibility and 57.9% felt that guidelines would not improve their diagnostic ability. The respondents were, in general, favourably disposed towards CPGs. Most had already read some guidelines, and about two thirds were prepared to use them. Almost all respondents felt that general practitioners should be involved in the development of guidelines for use in general practice. These general practitioners felt that guidelines were likely to help them treat patients than to make a diagnosis. Despite these favourable attitudes, many practitioners felt that guidelines would limit their personal flexibility in caring for patients. Organisations developing or implementing CPGs in general practice should address these concerns.
    East African medical journal 02/2001; 78(1):30-4.
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    ABSTRACT: Praziquantel was given every eight weeks for two years to children aged under six years of age, living in a Schistosoma haematobium endemic area. Infection with S. haematobium and haematuria were examined in urine and antibody profiles (IgA, IgE, IgM, IgG1, IgG2, IgG3, and IgG4) against S. haematobium adult worm and egg antigens were determined from sera collected before each treatment. Chemotherapy reduced infection prevalence and mean intensity from 51.8% and 110 eggs per 10 ml urine, respectively, before starting re-treatment programme to very low levels thereafter. Praziquantel is not accumulated after periodic administration in children. Immunoglobulin levels change during the course of treatment with a shift towards 'protective' mechanisms. The significant changes noted in some individuals were the drop in 'blocking' IgG2 and IgG4 whereas the 'protecting' IgA and IgG1 levels increased. The antibody profiles in the rest of the children remained generally unchanged throughout the study and no haematuria was observed after the second treatment. The removal of worms before production of large number of eggs, prevented the children from developing morbidity.
    Memórias do Instituto Oswaldo Cruz 02/2001; 96 Suppl:157-64. · 1.36 Impact Factor
  • K Bhagat, J Kurashe, N Z Nyazema
    The Central African journal of medicine 05/2000; 46(4):108-11.
  • K Bhagat, N Z Nyazema
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    ABSTRACT: A plethora of articles are now being published in both local and international journals on research activities conducted on the human immunodeficiency virus (HIV) in Zimbabwe. Some of the bioethical issues they raise, however, are neither unique to HIV nor unique to developing countries. In this article we discuss several of these issues, including the failure to provide interventions of known efficacy, ethical relevance of study design, informed consent, and exploitation. A challenge raised by much of the research in HIV/AIDS is whether, or under what conditions, it is ethical in research to fail to provide an intervention of known efficacy. The further we diverge from this situation, in which an effective, easy to implement intervention is available, to situations that resemble the controversial international clinical trials to prevent perinatal transmission of HIV the less clear the ethical mandate becomes. In relation to clinical trials the debate has focused on whether the standard of care in the United States--an expensive and complex regimen of Zidovudine--must be provided to all HIV infected pregnant women who join a research study in developing countries. Different scientists and scholars in bioethics have drawn the line differently in terms of what interventions routinely available in the developed world must be provided to research participants in developing countries. At an extreme, no one suggests that the most expensive and complex of Western tertiary care, for example, renal dialysis or coronary bypass, must be provided in research conducted in Zimbabwe. Indeed, public debates about the HIV perinatal transmission trials have not even focused on whether the women in the trials should be provided with HIV combination therapy as they would be in the West or whether they should even have the Zidovudine continued post partum.
    The Central African journal of medicine 05/2000; 46(4):105-7.
  • P R Gwatirisa, J Ndamba, N Z Nyazema
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    ABSTRACT: To determine the impact of health education on knowledge, attitudes and practices (KAP) with regards to use of a plant molluscicide in snail control. Repeat cross sectional survey. Chiweshe communal lands. Males and females--age range 13 to 87 years. Changes in: KAP after health education, water usage pattern, water contact behaviour, willingness to participate in use of P. dodecandra. A high proportion of the community indicated prior knowledge of schistosomiasis during both knowledge, attitudes and practices (KAP) surveys. In the follow up KAP survey changes in the community's water contact behaviour as well as their practices in relation to sanitation were reported. The involvement of the community in the application of P. dodecandra during the course of the study ensured continued support and participation of the community. This was evidenced in the follow up survey when it was apparent that the community's attitude towards schistosomiasis had been influenced by the different activities that had taken place. Changes in the community's KAP with regards to schistosomiasis control, can be interpreted as an indication of the impact of the health education delivered during the course of the study. Health education should, therefore, precede programmes that require full participation of the community, as this enables the community to make informed decisions regarding their participation.
    The Central African journal of medicine 05/1999; 45(4):94-7.
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    ABSTRACT: To assess peoples' perceptions and knowledge about malaria transmission and control with special reference to the use of plants as mosquito repellents. Cross sectional study. Mandeya ward "A" (33 degrees E and 18 degrees 30' S), Honde Valley, Zimbabwe. 226 household heads present when interview was conducted. Mosquito control methods, spraying coverage, plants used to repel mosquitoes and reasons for using them. 215 (95.0%) of the respondents' homes had been sprayed and their understanding of malaria transmission was not related to compliance with the National Malaria Control Programme (NMCP). Taking mosquito control measures was related to knowledge of malaria transmission, with 24 (75.0%) of those who did not know, taking no measures of their own. The use of plants was mentioned by 50 (23.5%) of the respondents and the reasons given were that they were cheap 43 (86.0%), effective five (10.0%) and locally available two (4.0%). The plant which was mentioned as being used by all age groups was L. javanica 25 (50.0%) and the other plants were used to a lesser extent. Forty six (92.0%) of the people said that they had used plants for mosquito control. The leafy part of the plant was used by 43 (86.0%) and a fresh preparation 43 (86.2%) gave better protection than a dry one. The plants were crushed and applied on the skin by eight people (14.6%), burnt by 36 people (72.8%) and used in their original form by six people (12.6%) and used once per by day 42 people (84.0%). One of the important points to emerge from this study is that, despite widespread knowledge about the morbidity of malaria, understanding about its prevention was generally low and this has negative implications on an integrated control programme.
    The Central African journal of medicine 04/1999; 45(3):64-8.
  • Parasitology International - PARASITOL INT. 01/1998; 47:278-278.
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    ABSTRACT: To determine the prevalence of gonorrhoea and knowledge about sexually transmitted infections in a farming community. Cross sectional study. Commercial farming area, Zimbabwe. 1,005 individuals aged between 15 and 60 years. Prevalence rates, knowledge of gonorrhoea and other sexually transmitted infections (STIs) by age and sex. Knowledge of gonorrhoea and other STIs was higher while knowledge of AIDS was lower among males than females. Frequency of past history of STIs in five years was significantly higher among males than females (OR 3.22; 95% CI 2.45 to 4.25). Physical examination revealed that 14% of males and 22% of females had other STIs besides gonorrhoea. The prevalence of gonorrhea was 18.4% (95% CI 16.0 to 20.8) and was higher among females than males (OR 2.77; 95% CI 1.97 to 3.90). Thirty one percent of the gonorrhoea infections were due to penicillinase producing Neisseria gonorrhoeae. Our findings emphasize the disparity between knowledge and practices with regards to STIs, and the importance of STIs as potential targets for and indices in the fight against human immunodeficiency virus (HIV) infection.
    The Central African journal of medicine 08/1997; 43(7):192-5.
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    ABSTRACT: The study aimed to establish if there was any relationship between the blood group of the human host and schistosomiasis prevalence, intensity, incidence and related organ pathology. Urine and stool specimens were collected from the 735 school children attending a rural school in Zimbabwe to determine the Schistosoma haematobium and S. mansoni infection status of the children. The parasitology results were used to calculate prevalence and intensity of schistosomiasis infection. All the children, irrespective of infection status, were examined for signs of organ damage using ultrasonography before those that were infected were treated using a single dose of praziquantel. A blood specimen was taken from each child for blood group determination. Exactly 1 year later, parasitology was repeated to allow calculation of annual incidence of schistosomiasis infection. Of the children studied, 212 (28.8%) were of blood group 'A', 156 (21.2%) were of blood group 'B' while 367 (49.9%) belonged to blood group 'O'. The prevalence of S. haematobium was 59.6% (n = 438) while that of S. mansoni was 15.60% (n = 115). S. haematobium infection was detected among 129 (60.8%) children belonging to blood group 'A': 225 (61.30%) of blood group 'O' and 84 (53. 80%) of those belonging to blood group 'B'. S. mansoni infection was detected among 65 (30.70%) blood group 'A' children while 37 (10.10%) blood group 'O' and 13 (8.30%) blood group 'B' children were infected. Intensity, annual incidence of S. haematobium infection and related organ pathology was significantly higher among children of blood group 'A' and lowest among blood group 'O' children (P < 0.01, F-value = 6.13). Similarly, S. Mansoni intensity and incidence of infection and related liver lesions were highest among children of blood group 'A' (P < 0.005, F-value = 11.45).
    Acta Tropica 05/1997; 65(3):181-90. · 2.79 Impact Factor
  • H. Friis, E. Gomo, N. Nyazema, N. D. Hlovu
    Nutrition 01/1997; 13(3):275-275. · 2.86 Impact Factor
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    ABSTRACT: A study to investigate the prevalence of schistosomiasis and hepatitis B viral (HBV) infection, among pregnant women was carried out at Howard Hospital in Chiweshe District, Zimbabwe. Urine and stool specimens, for the determination of Schistosoma haematobium and Schistosoma mansoni respectively, were collected from 299 pregnant women attending an antenatal clinic. In addition, five ml of blood was collected from each of the women for the determination of hepatitis B serum markers, HBsAg and anti-HB antibodies. S. haematobium and S. mansoni infection prevalence was 50 pc among the pregnant women. About 13 pc of them had both infections. Frequency of stillbirth or infant mortality was 16 pc among expectant mothers who previously had schistosoma infection compared to 8 pc among those who had no history of schistosomal infection. Only 2 pc of the pregnant women tested positive for the two hepatitis B markers. However, further hepatitis B prevalence B studies still have to be carried out with a larger cohort of pregnant women in schistosomiasis endemic areas. At the same time the seroconversion rates of children born from mothers living in schistosomiasis endemic areas would need to be compared with those of non-endemic areas before any changes in the recommended vaccination schedule are made.
    The Central African journal of medicine 10/1995; 41(9):288-92.
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    ABSTRACT: A possible synergy has been shown between chemotherapy with praziquantel, PZQ (normally administered once in 12 months), and the immune system in mice infected with schistosomiasis. This has been supported by a reduction in the effectiveness of PZQ against adult schistosomes in T and B lymphocyte depleted mice. We have investigated the effect of a standard dose, 40 mg/kg, of PZQ on polymorphonucluecytes (PMN) spreading, granulocytes chemotaxis, adherence and lymphocyte blastogenic responses. Blood samples were collected from volunteer children with or without urinary schistosomiasis infection, after obtaining their consent. The results obtained showed that PZQ, three hours after administration (plasma half life; 1.5 h), appeared to significantly (p < 0.001) enhance the chemotactic affect of N-fmlp and the blastogenic effect of soluble schistosome egg antigen (SEA) and phytohaemaglutanin (PHA). It would be reasonable to conclude that these observed effects of PZQ may contribute to the overall mode of action of PZQ.
    The Central African journal of medicine 09/1995; 41(9):284-8.
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    ABSTRACT: During a cross sectional study on the prevalence and incidence of gonorrhoea, Neisseria gonorrhoeae was isolated from 185 people aged between 16 and 60 years. In vitro activity of six antimicrobial antibacterial agents, penicillin, erythromycin, tetracycline, cotrimoxazole, ceftriaxone and norfloxacin on the isolated N. gonorrhoeae were carried out. The results obtained showed that, of all 111 isolates, 48 (43.2 pc) were penicillinase producing N. gonorrhoeae (PPNG) and 63 (56.8 pc) were non PPNGs. Over 90 pc of both PPNG and non PPNG isolates were sensitive to tetracyline and erythromycin. Seventy five pc of the PPNG and 45 pc non-PPNG were not sensitive to two units of penicillin. Both PPNG and non-PPNG were less sensitive to cotrimoxazole 25 micrograms. Norfloxacin and ceftriaxone were over 70 pc effective but were extremely expensive for most people who got infected.
    The Central African journal of medicine 04/1995; 41(3):83-6.
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    ABSTRACT: A total of 286 traditional healers, 85% of them registered with the Zimbabwe National Traditional Healers' Association (ZINATHA), in five administrative provinces of Zimbabwe, were interviewed to assess their knowledge about the signs and symptoms of urinary schistosomiasis. Information on the names of plants used to treat Schistosoma haematobium infections was solicited. Haematuria was mentioned by 99% of the traditional healers to be the most obvious sign of S. haematobium infection. General body weakness, increased urinary frequency and pain on micturition also were reported to be some of the signs of infection. Eight plant materials were identified as the most commonly used for the treatment of S. haematobium. The plants were identified and parts collected to investigate their antischistosomal properties. The plant materials were prepared according to the guidelines of the traditional healers and their efficacy determined by administering the crude extracts orally to hamsters infected with S. haematobium cercariae. The results obtained suggested that plant extracts from Abrus precatorius (Leguminosae), Pterocarpus angolensis (Leguminosae) and Ozoroa insignis (Anacardiaceae) were lethal to adult schistosomes.
    Journal of Ethnopharmacology 05/1994; 42(2):125-32. · 2.76 Impact Factor