A PCR-based assay for the detection of Schistosoma japonicum from human samples

Background and Objective@#Schistosoma japonicum is the causative agent of schistosomiasis in the Philippines. Current diagnostics suffer from low sensitivity and accuracy, hence an accurate and reliable diagnosis of schistosomiasis is essential for its prevention and control. In this study, a PCR-based assay for the detection of Schistosoma japonicumfor patient stool and serum samples was developed.@*Methodology@#Three candidate primer sets targeting mitochondrial genes COX3, NAD4, and NAD5 were assessed. COX3 primer pair was used for the rest of the study for sensitivity, specificity, and performance testing. Lastly, the assay using COX3 primer pair was compared to Kato-Katz and circumoval precipitin test (COPT).@*Results@#COX3 and NAD5 primers showed suitability for the assay as sequencing analyses gave high similarities of 96-98% for S. japonicum, while NAD4 showed no similarity to any organisms. The PCR-assay was shown to have a detection limit of 4 ng/ul DNA and was specific only to S. japonicum. The assay detected seven out of ten S. japonicum-spiked stool samples and ten out of ten S. japonicum-spiked serum samples. Comparative performance testing with Kato-Katz and COPT showed high specificity of 100% for both samples, but low sensitivity for formalin-fixed stool samples and stored serum samples. @*Conclusion@#This study developed a sensitive and specific PCR-based assay to detect S. japonicum from human samples. Results suggest that this PCR assay could be useful for the detection of S. japonicum in fresh clinical samples and can be further improved as a reference to improve other diagnostic assays for schistosomiasis.

Continued circulation of a single genotype of dengue virus serotype 2 in the Philippines

OBJECTIVE@#To obtain descriptive information of behavioral pattern in Chinese school-aged children with cleft lip and palate.@*METHODS@#A total of 93 cleft lip and palate patients between the age of 6-11 year-old and treated at West China Stomatology Hospital were selected. And another 100 unaffected controls, matched for age and gender, were recruited randomly from a common primary school in Chengdu. Chart review of medical records was used to obtain psychosocial checklists. Scores were compared with published norms and controls to evaluate the risk of problems, separately for three diagnostic groups.@*RESULTS@#The patients group had lower scores of social and academic competencies, especially those with facial deformity or speech problem. No difference was found in the aspect of activity competency. All patients showed elevations in behavior problems. But the type of behavior problems varied in different genders.@*CONCLUSIONS@#Chinese school-aged children with cleft lip and palate are at raised risk for social and academic difficulties. Specific pattern of behavior problems displays differently depending on gender of the patient.