Biomaterial Database

Detection of Plasmodium falciparum: a comparison of six cloned DNA probes. 1991

L E Andrade, and L E Cardona, and C Vergara

Departamento de Microbiología, Fac. de Salud, Universidad del Valle, Cali, Colombia.

Probes pRepHind, Rep20, p242B1-1, pPF-14, clone 26 and 34 were compared for their applicability to detect P. falciparum in field conditions. Ninety four clinical samples from patients living in the malaria endemic area of Tumaco (Pacific Coast) plus 88 from Villavicencio (Eastern Plains) were tested in "dotblot" hybridization experiments. Probes Rep20, p242B1-1, pRepHind and pPF-14 detected up to 17 pg of purified P. falciparum DNA, while clone 26 and clone 34 detected up to 425 pg DNA. Probes pPF-14, P242B1-1, pRepHind and Rep 20 exhibited comparable detection levels of parasites in infected blood samples. Sensitivity declined from 69-94% in subjects with parasitemias higher than 10.000 par./ul to 15-42% in subjects with parasitemias lower than 100 par./ul. pPF-14 and p24B1-1 showed the highest sensitivity, while clone 26 and 34 presented significantly lower sensitivities. All probes were shown to be highly specific. Detection levels are dependent on specimen treatment. Treatment consisting of serum removal, Triton X-100 lysis, Proteinase K digestion, Phenol and Chloroform extractions followed by Ethanol precipitation yielded 100% sensitivity for specimens with parasite density higher than 1,000 par./l.

UI	MeSH Term	Description	Entries
D009693	Nucleic Acid Hybridization	Widely used technique which exploits the ability of complementary sequences in single-stranded DNAs or RNAs to pair with each other to form a double helix. Hybridization can take place between two complimentary DNA sequences, between a single-stranded DNA and a complementary RNA, or between two RNA sequences. The technique is used to detect and isolate specific sequences, measure homology, or define other characteristics of one or both strands. (Kendrew, Encyclopedia of Molecular Biology, 1994, p503)	Genomic Hybridization,Acid Hybridization, Nucleic,Acid Hybridizations, Nucleic,Genomic Hybridizations,Hybridization, Genomic,Hybridization, Nucleic Acid,Hybridizations, Genomic,Hybridizations, Nucleic Acid,Nucleic Acid Hybridizations
D010963	Plasmodium falciparum	A species of protozoa that is the causal agent of falciparum malaria (MALARIA, FALCIPARUM). It is most prevalent in the tropics and subtropics.	Plasmodium falciparums,falciparums, Plasmodium
D001800	Blood Specimen Collection	The taking of a blood sample to determine its character as a whole, to identify levels of its component cells, chemicals, gases, or other constituents, to perform pathological examination, etc.	Blood Specimen Collections,Collection, Blood Specimen,Collections, Blood Specimen,Specimen Collection, Blood,Specimen Collections, Blood
D004912	Erythrocytes	Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.	Blood Cells, Red,Blood Corpuscles, Red,Red Blood Cells,Red Blood Corpuscles,Blood Cell, Red,Blood Corpuscle, Red,Erythrocyte,Red Blood Cell,Red Blood Corpuscle
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012680	Sensitivity and Specificity	Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)	Specificity,Sensitivity,Specificity and Sensitivity
D015342	DNA Probes	Species- or subspecies-specific DNA (including COMPLEMENTARY DNA; conserved genes, whole chromosomes, or whole genomes) used in hybridization studies in order to identify microorganisms, to measure DNA-DNA homologies, to group subspecies, etc. The DNA probe hybridizes with a specific mRNA, if present. Conventional techniques used for testing for the hybridization product include dot blot assays, Southern blot assays, and DNA:RNA hybrid-specific antibody tests. Conventional labels for the DNA probe include the radioisotope labels 32P and 125I and the chemical label biotin. The use of DNA probes provides a specific, sensitive, rapid, and inexpensive replacement for cell culture techniques for diagnosing infections.	Chromosomal Probes,DNA Hybridization Probe,DNA Probe,Gene Probes, DNA,Conserved Gene Probes,DNA Hybridization Probes,Whole Chromosomal Probes,Whole Genomic DNA Probes,Chromosomal Probes, Whole,DNA Gene Probes,Gene Probes, Conserved,Hybridization Probe, DNA,Hybridization Probes, DNA,Probe, DNA,Probe, DNA Hybridization,Probes, Chromosomal,Probes, Conserved Gene,Probes, DNA,Probes, DNA Gene,Probes, DNA Hybridization,Probes, Whole Chromosomal
D016054	DNA, Protozoan	Deoxyribonucleic acid that makes up the genetic material of protozoa.	Protozoan DNA
D016778	Malaria, Falciparum	Malaria caused by PLASMODIUM FALCIPARUM. This is the severest form of malaria and is associated with the highest levels of parasites in the blood. This disease is characterized by irregularly recurring febrile paroxysms that in extreme cases occur with acute cerebral, renal, or gastrointestinal manifestations.	Plasmodium falciparum Malaria,Malaria, Plasmodium falciparum