ABSTRACT
BACKGROUND: Malaria still poses one of the major threats to human health. Development of effective antimalarial drugs has decreased this threat; however, the emergence of drug-resistant Plasmodium falciparum, a cause of Malaria, is disconcerting. The antimalarial drug chloroquine has been effectively used, but resistant parasites have spread worldwide. Interestingly, the withdrawal of the drug reportedly leads to an increased population of susceptible parasites in some cases. We examined the prevalence of genomic polymorphisms in a malaria parasite P. falciparum, associated with resistance to an antimalarial drug chloroquine, after the withdrawal of the drug from Indonesia. RESULTS: Blood samples were collected from 95 malaria patients in North Sulawesi, Indonesia, in 2010. Parasite DNA was extracted and analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) for pfcrt and pfmdr1. In parallel, multiplex amplicon sequencing for the same genes was carried out with Illumina MiSeq. Of the 59 cases diagnosed as P. falciparum infection by microscopy, PCR-RFLP analysis clearly identified the genotype 76T in pfcrt in 44 cases. Sequencing analysis validated the identified genotypes in the 44 cases and demonstrated that the haplotype in the surrounding genomic region was exclusively SVMNT. Results of pfmdr1 were successfully obtained for 51 samples, where the genotyping results obtained by the two methods were completely consistent. In pfmdr1, the 86Y mutant genotype was observed in 45 cases (88.2%). CONCLUSIONS: Our results suggest that the prevalence of the mutated genotypes remained dominant even 6 years after the withdrawal of chloroquine from this region. Diversified haplotype of the resistance-related locus, potentially involved in fitness costs, unauthorized usage of chloroquine, and/or a short post-withdrawal period may account for the observed high persistence of prevalence.
Subject(s)
Chloroquine/therapeutic use , Drug Resistance/genetics , Malaria, Falciparum/drug therapy , Membrane Transport Proteins/genetics , Multidrug Resistance-Associated Proteins/genetics , Polymorphism, Genetic , Protozoan Proteins/genetics , Antimalarials/therapeutic use , DNA, Protozoan/chemistry , DNA, Protozoan/genetics , Drug Resistance, Multiple/genetics , Gene Frequency , Genotype , Geography , Haplotypes , High-Throughput Nucleotide Sequencing/methods , Indonesia , Malaria, Falciparum/parasitology , Mutation , Polymerase Chain Reaction , Polymorphism, Restriction Fragment LengthABSTRACT
The objective of this study was to determine the efficacy of live and killed probiotics to decrease the presence of hydrogen using the breath hydrogen test (BHT). This pretest-posttest control group design single blinded randomized study was performed in 5 government elementary schools in Tuminting subdistrict, Manado, Indonesia from March to May 2008. The study for inclusion as subjects consisted of healthy 10-12 year old children with heights and weights within normal limits using the Centers for Disease Control (CDC) criteria whose BHT was 220 parts per million (ppm), indicating lactose malabsorption. One hundred thirty children were screened, 86 met criteria, 43 children were randomized into two groups. Thirty-nine children who were given live probiotic and 40 children who were given killed probiotic completed the study. There was a significant difference when comparing the BHT results before and 120 minutes after giving probiotic for the children taking both the live and the killed probiotic (p < 0.001). When the children taking the live and killed probiotics were compared, there was no difference in the BHT at 120 minutes of probiotic (p = 0.453) by t-test. The administration of live or killed probiotic for 2 weeks can decrease the results of a BHT in children with lactose malabsorption. No adverse reactions attributable to treatment were noted.