ABSTRACT
A rapid DNA extraction was used for T. cruzi detection in triatomines dry fecal spots collected on filter paper and analyzed by PCR. Fifty T. infestans were fed on experimentally infected Balb/C mice with high T. cruzi parasitemia and divided into five groups of ten triatomines, and 100 triatomines were infected with lower parasitemia and divided into five groups of 20 triatomines. One dry fecal spot was analyzed per group on days 1, 2, 3, 4 and 5 post feeding. Amplification targeted T. cruzi TCZ sequence and resulted positive from day 4 after bugs feeding in the two models (high and lower parasitemial. The rapid DNA isolation and PCR proposed are suitable for detection of T. cruzi DNA in filter paper and should be considered in field research.
Subject(s)
Insect Vectors/parasitology , Triatoma/parasitology , Trypanosoma cruzi/isolation & purification , Animals , Chagas Disease/diagnosis , Chagas Disease/parasitology , DNA, Protozoan/chemistry , DNA, Protozoan/genetics , Feces/parasitology , Gene Amplification , Humans , Parasitemia/diagnosis , Parasitemia/parasitology , Polymerase Chain Reaction/methods , Sensitivity and Specificity , Trypanosoma cruzi/geneticsSubject(s)
Chagas Disease/diagnosis , Insect Vectors/parasitology , Triatoma/parasitology , Trypanosoma cruzi/isolation & purification , Animals , Chagas Disease/genetics , Chagas Disease/parasitology , DNA Primers/genetics , DNA, Protozoan/genetics , Humans , Mice , Mice, Inbred BALB C , Microscopy/methods , Polymerase Chain Reaction/methods , Repetitive Sequences, Nucleic Acid/genetics , Trypanosoma cruzi/geneticsABSTRACT
There is no paucity of methods for diagnosing Cryptosporidium spp. infection. The merits of immunoassays notwithstanding, microscopic identification of Cryptosporidium spp. oocysts in fecal samples remains an important diagnostic procedure. It owes the persistence of its use to such characteristics as dispensing with expensive equipment and kits, requiring only basic laboratory facilities, and having a low probability of false positive results when permanent slides are prepared, which can be re-examined in case of doubt. Cryptosporidium spp. oocysts can be readily identified in fecal smears prepared according to a regressive iron hematoxylin staining technique. The number of steps and their duration, as well as costs, were reduced to a minimum without loss of image quality and permanence of the preparations.
