Method: The stem powder of T. crispa was soaked in absolute ethanol for 72 hours. The resulting ethanolic extract was screened for the presence of phytochemicals. Vero cells monolayer in 96-well plate was infected with RH strain of T. gondii and treated with concentrations of the EETC, Veratrine alkaloid, and clindamycin ranging from 1.56 to 200 μg/mL. MTT assay was conducted after 24 hours to evaluate the cytotoxicity and antiparasitic activities of the EETC. Four and 24 hours treatment models were adapted to assess the infection index and intracellular proliferation of T.

Results: The study revealed that the EETC had no cytotoxic effects on Vero cells with IC50 = 179 μg/mL, as compared to clindamycin (IC50 = 116.5 μg/mL) and Veratrine alkaloid (IC50 = 60.4 μg/mL). The EETC had good anti-toxoplasma activities with IC50 = 6.31 μg/mL in comparison with clindamycin (IC50 = 8.33 μg/mL) and Veratrine alkaloid (IC50 = 14.25 μg/mL). The EETC caused more than 70% and 80% reduction in infection index and intracellular proliferation in both treatment models, respectively.

METHODS: A total of 484 migrant workers originating from rural locations in neighbouring countries, namely, Indonesia (n = 247, 51.0%), Nepal (n = 99, 20.5%), Bangladesh (n = 72, 14.9%), India (n = 52, 10.7%) and Myanmar (n = 14, 2.9%) were included in this study.

METHODS: The demographic profiles for each participant were obtained through a questionnaire survey prior to blood collection. A total of 389 participants were recruited and blood samples screened for the presence of anti-Toxoplasma IgG and IgM antibody using an ELISA commercial kit, SERION ELISA classic Toxoplasma gondii IgG and IgM.

RESULTS: The overall T. gondii seroprevalence was 69.6% with 56.8% seropositive for anti-Toxoplasma IgG, 7.7% seropositive for anti-Toxoplasma IgM and 5.1% seropositive for both IgG and IgM antibodies. The presence of both antibody classes in blood samples indicated high avidity, suggesting latent infection. Univariate analysis revealed significant associations that included; age, ethnicity, location and employment status while, significant lifestyle factors included source of drinking water and eating style. A multifactorial statistical model that incorporated all the significant effects from the first-stage univariate analyses listed above revealed that age and ethnicity were the two dominant and independent effects on IgG seroprevalence. For seroprevalence of IgM, the multifactorial model revealed a significant interaction between work and accommodation. IgM seroprevalence was higher among the unemployed inhabitants of PPR (Program Perumahan Rakyat) than those living in non-PPR accommodation, and higher than among the employed irrespective of their accommodation.

RESULTS: Yeast two-hybrid (Y2H) experiment was used to identify the binding partners of surface antigens of T. gondii by using SAG2 as bait. Colony PCR was performed and positive clones were sent for sequencing to confirm their identity. The yeast plasmids for true positive clones were rescued by transformation into E. coli TOP 10F' cells. The interplay between bait and prey was confirmed by β-galactosidase assay and co-immunoprecipitation experiment. We detected 20 clones interacting with SAG2 based on a series of the selection procedures. Following the autoactivation and toxicity tests, SAG2 was proven to be a suitable candidate as a bait. Thirteen clones were further examined by small scale Y2H experiment. The results indicated that a strong interaction existed between Homo sapiens zinc finger protein and SAG2, which could activate the expressions of the reporter genes in diploid yeast. Co-immunoprecipitation experiment result indicated the binding between this prey and SAG2 protein was significant (Mann-Whitney U-test: Z = -1.964, P = 0.05).