Random amplified polymorphic DNA analysis of DNA extracted from Trichuris trichiura (Linnaeus, 1771) eggs and its prospective application to paleoparasitological studies

Genetic relatedness and diversity of Capillaria species infecting bayad (Bagrus bajad) in upper Egypt

BACKGROUND

This study investigates the genetic characteristics of Capillaria isolates from the infected fish, Bagrus bajad, and their relation to human Capillaria philippinensis using Random Amplified Polymorphic DNA (RAPD-PCR) analysis. Fifteen fish Capillaria were isolated and compared to identified human C. philippinensis using six primers: M-are, M-1, G-7, G-11, G-15, and G-18.

RESULTS

All six primers successfully amplified DNA, highlighting their efficacy in distinguishing between human and fish Capillaria isolates. The analysis revealed distinctive banding patterns between fish and human isolates, with variations in size and number of DNA fragments. Additionally, genetic similarity analysis showed intriguing patterns of relatedness, with certain pairs exhibiting high similarity percentages. Comparative assessment of RAPD polymorphism demonstrated consistent findings of 100% polymorphism across all primers. The Unweighted Pair Group Method with Arithmetic Mean Algorithm (UPGMA) evaluated the closest relationship between human and fish isolates. These results underscore the utility of RAPD analysis in delineating the genetic diversity among Capillaria isolates from different hosts.

CONCLUSION

Overall, this study contributes to our understanding of the genetic variability and relatedness among Capillaria isolates, shedding light on their evolutionary dynamics and zoonotic potential.

Trichuris vulpis and T. trichiura infections among schoolchildren of a rural community in northwestern Thailand: the possible role of dogs in disease transmission

Background: Trichuriasis is an important soil-transmitted helminth infection caused by Trichuris trichiura. About one-tenth of the world population may be infected. Incidentally, T. vulpis or dog whipworm has been reported to infect humans based on the egg size. However, an overlapping egg dimension occurs between T. trichiura and T. vulpis leading to the potential for misdiagnosis. Objective: Develop a PCR method to differentiate T. trichiura and T. vulpis eggs in stool samples and to investigate the prevalence of both whipworms in humans and dogs in a rural community in Thailand. Materials and methods: We determined and compared the small subunit ribosomal RNA sequences of both species of whipworms for developing species-specific PCR diagnosis. After validation of the method, we conducted a cross-sectional survey at Ta Song Yang District in Tak Province, northwestern Thailand in 2008. Stool samples were randomly recruited from 80 schoolchildren (36 males, 44 females) and 79 dogs in this community. Results: Fifty-six individuals harbored Trichuris eggs in their stools. The PCR-based diagnosis revealed that 50 cases were infected with T. trichiura and six (10.7%) were co-infected with both T. trichiura and T. vulpis. Although the dimension of Trichuris eggs provided some diagnostic clues for species differentiation, a remarkable variation in the length of these whipworm eggs was observed among samples that could lead to misdiagnosis. Conclusion: Both T. trichiura and T. vulpis eggs were detected in stool samples of dogs that roamed around this community, highlighting the potential reservoir role of dogs in the transmission of both human and dog whipworms in this population.

Paleoparasitological studies on mummies of the Joseon Dynasty, Korea

Paleoparasitology is the application of conventional or molecular investigative techniques to archeological samples in order to reveal parasitic infection patterns among past populations. Although pioneering studies already have reported key paleoparasitological findings around the world, the same sorts of studies had not, until very recently, been conducted in sufficient numbers in Korea. Mummified remains of individuals dating to the Korean Joseon Dynasty actually have proved very meaningful to concerned researchers, owing particularly to their superb preservation status, which makes them ideal subjects for paleoparasitological studies. Over the past several years, our study series on Korean mummies has yielded very pertinent data on parasitic infection patterns prevailing among certain Joseon Dynasty populations. In this short review, we summarized the findings and achievements of our recent paleoparasitological examinations of Joseon mummies and discussed about the prospects for future research in this vein.