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Khoo Hoon Eng

Publications and source records attributed to Khoo Hoon Eng.

5 recordsLinked to original sources

Medical education in Southeast Asia: emerging issues, challenges and opportunities.

CONTEXT: Medical education in Southeast Asian countries is undergoing rapid changes, with the realignment of medical schools' curricula to meet national needs and priorities, the adoption of and experimentation with innovations, and greater emphasis on staff development initiatives. The Medical Education Unit of the National University of Singapore undertook a project to compile the educational processes taking place in these medical schools. METHOD: This was a process-focused initiative. We developed a custom-made questionnaire that emphasised narrative description. We compiled profiles of 30 selected medical schools in the Southeast Asian region and, after editing and review, published these profiles. This report summarises the key findings from the project. FINDINGS: Medical schools in Southeast Asia are in a dynamic state. Schools are gradually adopting student-centred learning approaches, including problem-based learning. Many schools offer their students early clinical training, opportunities for out-of-hospital postings, and student-selected electives. Multiple-choice questions and oral examinations are almost universally used in student assessment. Portfolios and self- and peer-assessments are seldom used. Major challenges faced by the schools involve shortages of qualified staff and financial constraints. Major goals for the future include the implementation of student-centred learning, the revamping of the assessment process, and staff training. CONCLUSIONS: This is a compilation of self-reported profiles of selected medical schools where we encouraged self-reflection and analysis. As with other surveys, there could be potential self-selection bias. Nevertheless, the profiles of these selected schools provide a broad overview of the status of medical schools in Southeast Asia.

Asia, Southeastern↗

Optical immunoassay for snake venom detection.

A sensitive and specific optical immunoassay (OIA) has been developed for snake venom detection. The assay is based on the principle of detection of physical changes in thickness of molecular thin film resulting from specific binding events on an optical silicon chip (SILAS-I, ThermoBioStar, Colorado, USA). The reflection of white light through the thin film results in destructive interference of a particular wavelength of the light from gold to purple-blue depending on the thickness of the thin film formed or the amount of venom in the test sample. A prototype test kit for the simultaneous identification of species and semi-quantitative detection of venoms from four medically important snakes of South Vietnam (Trimeresurus albolabris, Calloselasma rhodostoma, Naja kaouthia and Ophiophagus hannah) has been developed. The kit can detect venom analytes in blood, plasma, urine, wound exudates, blister fluid or tissue homogenates. The efficacy of the test kit in snakebite diagnosis has been demonstrated in experimental envenomations and sample analytes taken from snakebite victims in South Vietnam. This rapid snake venom detection kit based on OIA technique is potentially applicable in the clinics as well as in the field.

Animals↗

Immunogenicity of venoms from four common snakes in the South of Vietnam and development of ELISA kit for venom detection.

The antigenicity and antigenic relationship between venoms of four common snakes in the South of Vietnam-Trimeresurus popeorum, Calloselasma rhodostoma, Naja naja and Ophiophagus hannah-were studied. Most of venom components expressed antigenicity and produced high titre antivenoms. The venoms share common components and antivenoms cross-reacted along them. Furthermore, cross-reactions were observed among non-common antigens, indicating that they share common epitopes. Hence, using single component as immunogen for species diagnosis of snakebites can reduce cross-reaction, perhaps may not be totally specific. A three-step affinity purification protocol was set up for preparation of species-specific antivenom antibodies. The steps involved affinity chromatography of IgG from hyper-immunized rabbit sera with protein A columns, immuno-affinity chromatography of monovalent antivenom antibodies with respective homologous venom columns, and immuno-absorption of cross-species reacting antibody molecules with heterologous venom columns. The antibodies were then used for construction of an enzyme-linked immunosorbent assay (ELISA) test kit. The kit can differentiate among the four common snake venoms in various types of samples with the detection limit of 0.2-1.6 ng/ml, depending on the type of samples and species of the snake. The efficacy of this kit for snake venom detection was successfully demonstrated in experimental envenomation in rats. Preliminary evaluation with 140 samples taken from 88 human snakebite victims in Vietnam showed that the kit could detect venom in human samples and would be a very useful tool for fast identification of snakebites in clinics.

Animals↗

A new avidin-biotin optical immunoassay for the detection of beta-bungarotoxin and application in diagnosis of experimental snake envenomation.

A highly sensitive avidin-biotin optical immunoassay (AB-OIA) has been developed for the detection of beta-bungarotoxin (beta-BuTx), a neurotoxin from the venom of Bungarus multicinctus, in whole blood, plasma, and urine. Affinity purified rabbit IgG anti-beta-BuTx antibody was immobilized on an optically active silicon surface (SILIAS wafer). The test sample was incubated and the antigen-antibody reaction was monitored by the addition of a biotinylated monoclonal antibody (mAb 15) specific to the toxin, avidin-horseradish peroxidase (HRP) and tetramethylbenzidine substrate. The silicon assay surface technology enables us to directly visualize a physical change in the optical thickness of the antibody thin film. The change in thickness is due to the specific capture of the toxin on the surface and when the substrate is added, the binding event is amplified, which then alters the reflected light path and a change in colour is visualized. The assay could detect beta-BuTx levels as low as 16 pg/ml in sample buffer and 100 pg/ml in whole blood or plasma. The AB-OIA is simple, requires only 40 microl of biological fluid and can be performed without specialized equipment. The efficacy of the test for detection of beta-BuTx in blood or plasma obtained from mice during experimental envenomation with B. multicinctus venom was demonstrated. The AB-OIA was also used to quantitate the postmortem level of beta-BuTx in various organs such as brain, liver, and kidney, as well as the tissue at the site of injection. Development of a simple, rapid snake toxin detection kit based on AB-OIA technique potentially applicable in the clinics as well as in the field is discussed.

Animals↗