Background: If malaria patients who cannot be treated orally are several hours from facilities for injections, rectal artesunate prior to hospital referral can prevent death and disability. The goal is to reduce death from malaria by having rectal artesunate treatment available and used. How best to do this remains unknown.
View Article and Find Full Text PDFBackground: This study was initiated to establish whether any South African ethnomedicinal plants (indigenous or exotic), that have been reported to be used traditionally to repel or kill mosquitoes, exhibit effective mosquito larvicidal properties.
Methods: Extracts of a selection of plant taxa sourced in South Africa were tested for larvicidal properties in an applicable assay. Thirty 3rd instar Anopheles arabiensis larvae were exposed to various extract types (dichloromethane, dichloromethane/methanol) (1:1), methanol and purified water) of each species investigated.
Background: This study was conducted to evaluate whether a selection of South African ethnomedicinal plants included in this study displayed insecticidal properties when screened against adult stages of the mosquito.
Methods: 381 crude extracts of 80 plant taxa in 42 families were sprayed onto ceramic tiles and screened using the cone bio-assay method for insecticide efficacy testing. Blood-fed, female Anopheles arabiensis mosquitoes were exposed to the treated tiles for a period of sixty minutes.
Background: This study was initiated to establish whether any South African ethnomedicinal plants (indigenous or exotic), that have been reported to be used traditionally to repel or kill mosquitoes, exhibit effective mosquito repellent properties.
Methods: Extracts of a selection of South African taxa were tested for repellency properties in an applicable mosquito feeding-probing assay using unfed female Anopheles arabiensis.
Results: Although a water extract of the roots of Chenopodium opulifolium was found to be 97% as effective as DEET after 2 mins, time lag studies revealed a substantial reduction in efficacy (to 30%) within two hours.
Placebo-controlled trials are controversial when individuals might be denied existing beneficial medical interventions. In the case of malaria, most patients die in rural villages without healthcare facilities. An artesunate suppository that can be given by minimally skilled persons might be of value when patients suddenly become too ill for oral treatment but are several hours from a facility that can give injectable treatment for severe disease.
View Article and Find Full Text PDFTuberculosis (Edinb)
December 2009
Artemisia afra [Jacq] (Asteraceae) phytotherapy is widely used for its medicinal properties in traditional practices. In this study we investigated whether extracts of A. afra are capable of controlling mycobacterial replication.
View Article and Find Full Text PDFAim: To investigate the traditional antidiabetic uses of indigenous or naturalised South African plants using an optimised screening and scoring method.
Materials And Methods: Eleven plant species were screened against Chang liver, 3T3-L1 adipose and C2C12 muscle cells measuring glucose utilisation in all three cell lines and toxicity in the hepatocytes and adipocytes only. A scoring system was devised to aid interpretation of results.
Objectives: The WHO recommends artemisinin-based combination therapies for treatment of uncomplicated falciparum malaria. At least 15 African countries have adopted artesunate plus amodiaquine as treatment policy. As no pharmacokinetic data on this combination have been published to date, we investigated its pharmacokinetic interactions and tolerability in healthy volunteers in Africa.
View Article and Find Full Text PDFFactors that relate to medium-term outcome in patients with pulmonary tuberculosis (PTB) who have completed the 2-month intensive phase of treatment are incompletely understood. The relationship between in vitro production of interferon-gamma (IFN-gamma), interleukins (ILs)-5 and -10 and drug levels determined after 2 months of drug therapy, to outcome at 24 months was studied prospectively. Cytokine concentrations were determined from culture supernatants after stimulation of whole blood with purified protein derivative (PPD) of Mycobacterium tuberculosis.
View Article and Find Full Text PDFBackground: The pharmacologic modulatory effects of the antibiotic, tunicamycin (TM), on multidrug-resistant human UWOV2 ovarian cancer cells are reported. The UWOV2 cell line was derived from a cystadenocarcinoma in a patient refractory to combination chemotherapy with actinomycin D, vincristine (VCR), cis-diaminedichloroplatinum (II) (CDDP) and doxorubicin (DXR). In an attempt to explain drug resistance in this cell line, we examined the effects of TM on their sensitivity to various anticancer drugs, the uptake, efflux and retention of [3H]VCR, and their ability to bind [14C]DXR and [3H]azidopine (AZD), a photoaffinity label of the multidrug transporter, P-glycoprotein (Pgp).
View Article and Find Full Text PDFBackground: Intra-rectal artesunate has been developed as a potentially life-saving treatment of severe malaria in rural village settings where administration of parenteral antimalarial drugs is not possible. We studied the population pharmacokinetics of intra-rectal artesunate and the relationship with parasitological responses in patients with moderately severe falciparum malaria.
Methods And Findings: Adults and children in Africa and Southeast Asia with moderately severe malaria were recruited in two Phase II studies (12 adults from Southeast Asia and 11 children from Africa) with intensive sampling protocols, and three Phase III studies (44 children from Southeast Asia, and 86 children and 26 adults from Africa) with sparse sampling.
Evaluation of sources of pharmacokinetic variation can facilitate optimization of tuberculosis treatment regimens by identification of avoidable sources of variation and of risk factors for low or high drug concentrations in patients. Our objective was to describe the pharmacokinetics of rifampin, isoniazid, pyrazinamide, and ethambutol in a cohort of tuberculosis patients established on first-line treatment regimens and to evaluate the determinants of pharmacokinetic variation. Plasma concentration-time profiles were determined for each of the drugs in 142 patients with drug-sensitive pulmonary tuberculosis after 2 months of daily treatment in hospital.
View Article and Find Full Text PDFEstablished in 1999, the Global Advisory Committee on Vaccine Safety advises the World Health Organization (WHO) on vaccine-related safety issues and enables WHO to respond promptly, efficiently, and with scientific rigor to issues of vaccine safety with potential global importance. The committee also assesses the implications of vaccine safety for practice worldwide and for WHO policies. We describe the principles on which the committee was established, its modus operandi, and the scope of the work undertaken, both present and future.
View Article and Find Full Text PDFThis paper provides a short account of the South African Defence Force's chemical and biological warfare programme during apartheid, specifically during the period 1980 to 1994. It examines the circumstances of recruitment of the scientists and physicians and their retention in the programme; details the 'scientific efforts' of the programme and its aberrations; and explores ethical issues in relation to the involvement of scientists in the programme.
View Article and Find Full Text PDFThe increasing prevalence and distribution of malaria has been attributed to a number of factors, one of them being the emergence and spread of drug resistant parasites. Efforts are now being directed towards the discovery and development of new chemically diverse antimalarial agents. The present study reports on the in vitro antiplasmodial activity of 134 plant taxa native to or naturalised in South Africa, representing 54 families, which were selected semi-quantitatively using weighted criteria.
View Article and Find Full Text PDFArtesunate, a semi-synthetic derivative of a naturally occurring anti-malarial artemisinin was compared with chloroquine in C57BL/6 mice infected with Plasmodium berghei Anka (PbA). A 7-day oral administration of artesunate prevented parasitaemia at 10 mg/kg/day. However, recrudescence of parasitaemia and cerebral malaria occurred upon cessation of treatment followed by death within 28 days.
View Article and Find Full Text PDFCyclophosphamide, administered in doses of 20 and 40 mg/kg body weight to pregnant inbred CBA mice on the third day of gestation (60 h after the estimated time of ovulation) reduced the activity of non-specific alkaline phosphatase (E.C. 3.
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