Thai Tea Seed Oil and Virgin Olive Oil Similarly Reduce Plasma Lipids: A Pilot Study within a Healthy Adult Male Population

The potential cardiovascular benefit of virgin olive oil (VOO) is widely recognized. However, the use of VOO at very high cooking temperatures makes these oils poorly suited for many Asian dishes. The use of tea seed oil (TSO) is increasing in Thailand, with TSO having a higher smoke point than VOO. The current study examines the effects of daily TSO intake in healthy adults. In a randomized, single-blind crossover design, 12 men consumed for 3 weeks 40 g day⁻¹ of food prepared with either TSO or VOO as a cooking oil. Plasma lipids, thiobarbituric acid reactive substances (TBARS), and oxidant defense enzyme activities are measured before and after each 3-week intervention period. Gas chromatography analysis of TSO and VOO demonstrates that both oils are equally high in monounsaturated fatty acid. The dietary incorporation of TSO and VOO for three weeks reduces low-density lipoprotein cholesterol (LDL-C) concentrations by 15% and 13%, respectively; with total cholesterol (TC) levels lowered by 10% in both groups. No significant changes in TBARS or antioxidant enzyme activity is observed. These results support the concept that Thai TSO can be utilized as a suitable and healthy alternative oil for high-temperature cooking in many Thai and Asian diets. Practical Applications: Tea seed oil from Camellia oleifera grown in Thailand has been recently reported to favorably lower lipid profiles in hamsters fed a high-fat diet in a manner similar to feeding refined olive oil or grapeseed oil. A pilot crossover trial is conducted to compare the effects of three weeks of daily intake of either TSO or VOO in healthy human adults. Consumption of both oils produced significant reductions in TC and LDL-C. Thai TSO leads to favorable lipid profiles and is a reasonable choice for many Thai and Asian food recipes.     

Monoclonal antibody-based immunohistochemical demonstration of Entamoeba histolytica in liver tissues of experimentally infected hamster (Mesocricetus auratus)

Histopathological changes and the presence of Entamoeba histolytica trophozoites was sequentially followed after intrahepatic inoculation of the parasites in 42 hamsters, 35 of which received no treatment whereas the remaining seven were treated with metronidazole. The liver tissues were examined for amoebic trophozoites by a monoclonal antibody (mAb)-based immunofluorescence assay (IFA), a mAb-based immunoperoxidase (IPx) and H & E staining. The number of hamsters developing abscesses was increased with time and was highest on day 30. Cellular infiltration with inflammatory cells and glycogen depletion were observed as early as day 5, followed thereafter by more intense inflammation of portal canals, periportal fibrosis, bile duct proliferation and hepatocyte degeneration. In 7 metronidazole-treated hamsters, no obvious pathological damage was seen. In a group of seven hamsters each, both IPx and IFA were positive in 3, 3, 4, 5 and 4 hamsters and in 3, 4, 3, 3 and 5 hamsters on days 5, 10, 15, 20 and 30, respectively. In 18 control hamsters, IPx, IFA and H & E were all negative. If the result from H & E was used as a gold standard, agreement between H & E and IFA and H & E and IPx were 91.4%, and 88.6%, respectively. Sensitivity and specificity were 93.8% and 89.5%, respectively for IFA, and 93.8% and 84.2%, respectively for IPx.     

Monoclonal antibody-based ELISA for the detection of circulating Entamoeba histolytica antigen in hepatic amebiasis in hamsters (Mesocricetus auratus)

Circulating amebic antigens were determined by using a sandwich ELISA with specific monoclonal antibody in the sera of 35 group I hamsters, 7 of which were sacrificed at intervals after hepatic inoculation with 500,000 axenically grown HM:1:IMSS strain of E. histolytica trophozoites, 7 group II infected hamsters in which metronidazole treatment was given and 18 group III uninfected controls. Amebic antigenemia was demonstrated in 5 of 7 (71.4%), 6 of 7 (85.7%), 7 of 7 (100%), 7 of 7 (100%) and 7 of 7 (100%) of group I hamsters on days 5, 10, 15, 20 and 30 of infections respectively, whereas 6 of 7 (85.7%) of group II hamsters were weakly positive, one was negative and all 18 group III hamsters were negative. The sensitivity of the assay was 100% after the animals were infected 15 days onwards. The level of antigenemia in hamsters of group I with abscess was significantly higher than those of the same group without abscess (p < 0.05). Absence or reduction of antigenemia after treatment could be interpreted to mean a positive test of cure and favorable therapeutic response. The MAb-PAb-based ELISA for the detection of circulating E. histolytica represents a simple and sensitive diagnostic test for invasive amebiasis in hamsters. Application of this test in amebic liver abscess patients should be of diagnostic value for indication of present infection or test of cure after successful treatment.     

Axenic cultivation of Entamoeba histolytica from liver abscess and its zymodeme

A local strain of Entamoeba histolytica, the HTH-56: MUTM from a human liver abscess was successfully axenized. The culture was initially established monoxenically in Diamond's TYI-S-33 medium in the presence of Crithidia luciliae and maintained at 34 +/- 0.5 degrees C. After 5 passages it was adapted to axenic cultivation by addition of 0.02% Bacto agar in Diamond's TYI-S-33 medium in place of Crithidia. Subcultures or replacement with fresh complete media were done twice or thrice for 7 days, after which the agar was omitted and a stable culture was obtained. Isoenzyme analysis showed that this strain of E. histolytica belonged to the zymodeme II pattern, which is one out of 10 pathogenic zymodemes of E. histolytica most commonly found among the virulent strains.