ABSTRACT
New astronomical observations point to a nucleosynthesis picture that goes beyond what was accepted until recently. The intermediate "i" process was proposed as a plausible scenario to explain some of the unusual abundance patterns observed in metal-poor stars. The most important nuclear physics properties entering i-process calculations are the neutron-capture cross sections and they are almost exclusively not known experimentally. Here we provide the first experimental constraints on the ^{139}Ba(n,γ)^{140}Ba reaction rate, which is the dominant source of uncertainty for the production of lanthanum, a key indicator of i-process conditions. This is an important step towards identifying the exact astrophysical site of stars carrying the i-process signature.
ABSTRACT
BACKGROUND: This study was conducted to determine the efficacy of the antimalarial artemisinin-based combination therapy (ACT) artesunate +sulfamethoxypyrazine/pyrimethamine (As+SMP), administered in doses used for malaria, to treat Schistosoma haematobium in school aged children. METHODOLOGY/PRINCIPAL FINDINGS: The study was conducted in Djalakorodji, a peri-urban area of Bamako, Mali, using a double blind setup in which As+SMP was compared with praziquantel (PZQ). Urine samples were examined for Schistosoma haematobium on days -1, 0, 28 and 29. Detection of haematuria, and haematological and biochemical exams were conducted on day 0 and day 28. Clinical exams were performed on days 0, 1, 2, and 28. A total of 800 children were included in the trial. The cure rate obtained without viability testing was 43.9% in the As+SMP group versus 53% in the PZQ group (Chi(2) = 6.44, p = 0.011). Egg reduction rates were 95.6% with PZQ in comparison with 92.8% with As+SMP, p = 0.096. The proportion of participants who experienced adverse events related to the medication was 0.5% (2/400) in As+SMP treated children compared to 2.3% (9/399) in the PZQ group (p = 0.033). Abdominal pain and vomiting were the most frequent adverse events in both treatment arms. All adverse events were categorized as mild. CONCLUSIONS/SIGNIFICANCE: The study demonstrates that PZQ was more effective than As+SMP for treating Schistosoma haematobium. However, the safety and tolerability profile of As+SMP was similar to that seen with PZQ. Our findings suggest that further investigations seem justifiable to determine the dose/efficacy/safety pattern of As+SMP in the treatment of Schistosoma infections. TRIAL REGISTRATION: ClinicalTrials.gov NCT00510159.
Subject(s)
Antimalarials/therapeutic use , Artemisinins/administration & dosage , Drug Combinations , Praziquantel/administration & dosage , Schistosoma haematobium/metabolism , Schistosomiasis haematobia/drug therapy , Sulfalene/administration & dosage , Adolescent , Animals , Artesunate , Child , Double-Blind Method , Female , Humans , Male , Pyrimethamine/administration & dosage , Time FactorsABSTRACT
The choice of artemisinin-based combination that is being adopted for malaria treatment in sub-Saharan Africa may depend on several factors, including cost, efficacy, side effects, and simplicity of administration. We tested the hypothesis that artesunate-sulfamethoxypyrazine-pyrimethamine is as efficacious as the four-dose regimen of artemether-lumefantrine for treatment of Plasmodium falciparum malaria. The study was carried out during two transmission seasons (2003 and 2004) in Sotuba, Mali. Participants at least 6 months of age with uncomplicated P. falciparum malaria were randomly assigned to receive artesunate-sulfamethoxypyrazine-pyrimethamine or artemether-lumefantrine. Treatment efficacy was assessed using the World Health Organization 28-day protocol. A total of 606 (303 in each arm) patients were enrolled. The cure rate was higher for artesunate-sulfamethoxypyrazine-pyrimethamine than for artemether-lumefantrine (98.7% versus 89.6%; P < 0.0001). After correction for cases of re-infection, the cure rates were 100% and 99.0%, respectively (P = 0.08). No serious adverse events occurred. Artesunate-sulfamethoxypyrazine-pyrimethamine is well-tolerated and effective against P. falciparum malaria. It showed an additional benefit of preventing new infections.
