ABSTRACT
Objective To provide the basis for the differentiation with similar species of intestinal flukes through observing the figure of Haplorchis pumilio. Methods Adults of H. pumilio were collected from the intestine of the cat which was infected with the encysted cercariae of H.pumilio for 45 days. The worms were observed after staining. Eggs and metacercariae of H.pumilio were collected and examined for their shape, size and morphological characteristics. Pseudorasbora parva, the fish host, was examined for the parasitized sites of metacercariae. Results The principal characteristics of the adults is the acetabulum degradation. There are only the genital sucker with 44-48 hamuli. The average measurement of eggs is 31.2?16.7 ?m with a smooth shell. Its aceromion is not evident. The average diameter of metacercariae is 168.5 ?m. There are squamous spines on metacercaria. The metacercariae only parasitize in the muscle between the basis of the fin and the fish body. The average measurement of metacercaria cyst is 445?95?m, with squamous spines on the body surface. Hamuli are found on the genital sucker of metacercaria cyst. Conclusion The morphological figures and parasitic sites of metacercaria, the genital sucker of the adult, and the number and form of the hamulus on the genital sucker provide basis for distinguishing H. pumilio from other intestinal flukes.
ABSTRACT
Objective To develop a method for detecting the genotype of Plasmodium vivax merozoite surface protein 1 (PvMSP-1) alleles. Methods According to the sequence characteristic of PvMSP-1, nested polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique was used to amplify the polymorphic region of ICB5-ICB6 which contains Q repeats and PvuII restriction site (Sal-1 type). The PCR product was digested by PvuII restriction endonuclease and the digested fragments were observed by 2% agarose gel electrophoresis. The allelic type was determined according to the banding pattern. Results Bands in size of 400 bp (Belem type ) and/or 470 bp (Sal-1 type ) appeared in all 98 P. vivax isolates, no band was found in negative control. After PvuII digestion, two Sal-1 type fragments (120 bp and 350 bp) were obtained from 45 samples of 470 bp. Single-band of 400 bp appeared in 3 of 40 samples with 400 bp as Belem type, two bands of 120 bp and 280 bp appeared from other 35 samples as recombination type III, and another 2 bands with 120 bp and 240 bp as Korean isolate. Conclusion The result showed that the nested PCR-RFLP may be applied in the detection and identification of the three PvMSP-1 allelic types in China.
ABSTRACT
Objective To develop methods of extracting DNA from malaria parasites on Giemsa-stained blood smears. Methods Improved Na2HPO4 method and Chelex-100 ion-exchange technique were used to extract DNA from Giemsa-stained or unstained blood smears. Nested PCR was employed for amplification and identification of allelotypes in the Plasmodium vivax merozoite surface protein-1(PvMSP-1). Results Target DNA bands appeared in all samples of unstained thick blood smears, while no DNA bands were visible in the fixed and stained thin smears. Both methods identified PvMSP-1 alleles from smears with parasitemia of ≥0.01%. Conclusion It is feasible to identify PvMSP-1 alleles from Giemsa-stained blood smear.