Matthew Choon‐Eng Gwee

Problem‐based learning (PBL) was first implemented by McMaster University medical school in 1969 as a radical, innovative, and alternative pathway to learning in medical education, thus setting a new educational trend. PBL has now spread widely across the globe and beyond the healthcare disciplines, and has prevailed for almost four decades. PBL is essentially a strategic learning system design, which combines several complementary educational principles for the delivery of instruction. PBL is specifically aimed at enhancing and optimizing the educational outcomes of learner‐centered, collaborative, contextual, integrated, self‐directed, and reflective learning. The design and delivery of instruction in PBL involve peer teaching and learning in small groups through the social construction of knowledge using a real‐life problem case to trigger the learning process. Therefore, PBL represents a major shift in the educational paradigm from the traditional teacher‐directed (teacher‐centered) instruction to student‐centered (learner‐centered) learning. PBL is firmly underpinned by several educational theories, but problems are often encountered in practice that can affect learning outcomes. Educators contemplating implementing PBL in their institutions should have a clear understanding of its basic tenets, its practice and its philosophy, as well as the issues, challenges, and opportunities associated with its implementation. Special attention should be paid to the training and selection of PBL tutors who have a critical role in the PBL process. Furthermore, a significant change in the mindsets of both students and teachers are required for the successful implementation of PBL. Thus, effective training programs for students and teachers must precede its implementation. PBL is a highly resource‐intensive learning strategy and the returns on investment (i.e. the actual versus expected learning outcomes) should be carefully and critically appraised in the decision‐making process. Implementation of PBL can be a daunting task and will require detailed and careful planning, together with a significant commitment on the part of educators given the responsibility to implement PBL in an institution. PBL can offer a more holistic, value‐added, and quality education to energize student learning in the healthcare professions in the 21^st century. Successful implementation of PBL can therefore help to nurture in students the development of desired ‘habits of mind, behavior, and action’ to become the competent, caring, and ethical healthcare professionals of the 21^st century. Thus, PBL can contribute to the improvement of the healthcare of a nation by healthcare professionals, but we need to do it right.

Pharmacology, as a basic medical science discipline, provides the scientific basis of therapeutics, i.e. the scientific foundation for safe and rational prescribing of drugs. The public, lay media, and the medical profession have raised serious concerns over the high incidence of errors of drug prescribing which compromise patient safety, including death of some patients, attributed mainly to inadequate teaching of medical pharmacology and, consequently, to medical graduates lacking skills in safe and effective drug prescribing. There is also overwhelming evidence that the pervasive and prevalent doctor-drug industry relationships have a strong influence over the prescribing habits and drug education of doctors. The British Pharmacological Society and American Association of Medical Colleges have crafted some insightful guidelines, including the learning of desired attitudes, for designing a medical pharmacology curriculum aimed at enhancing patient safety. This article will critically review the major issues relating to errors of drug prescribing, including the need to nurture the early development of desired attitudes which foster safe and rational drug prescribing. A simple educational approach, using a task analysis of drug prescribing, is applied to identify desired attitudes which should be incorporated into a basic pharmacology course for medical students in the twenty-first century.

Problem‐based learning (PBL) is essentially a learning system design that incorporates several educational strategies to optimize student‐centered learning outcomes beyond just knowledge acquisition. PBL was implemented almost four decades ago as an innovative and alternative pathway to learning in medical education in McMaster University Medical School. Since then, PBL has spread widely across the world and has now been adopted globally, including in much of Asia. The globalization of PBL has important cross‐cultural implications. Delivery of instruction in PBL involves active peer teaching‐learning in an open communication style. Consequently, this may pose an apparent serious conflict with the Asian communication style generally dominated by a cultural reticence. However, evidence available, especially from the PBL experience of some senior Korean medical students doing an elective in the University of Toronto Medical School and the cross‐cultural PBL experience initiated by Kaohsiung Medical University, strongly suggests creating a conducive and supportive learning environment for students learning in a PBL setting can overcome the perceived cultural barriers; that is, nurture matters more than culture in the learning environment. Karaoke is very much an Asian initiative. The Karaoke culture and philosophy provide a useful lesson on how to create a conducive and supportive environment to encourage, enhance and motivate group activity. Some key attributes associated with Asian culture are in fact consistent with, and aligned to, some of the basic tenets of PBL, including the congruence between the Asian emphasis on group before individual interest, and the collaborative small group learning design used in PBL. Although there are great expectations of the educational outcomes students can acquire from PBL, the available evidence supports the contention the actual educational outcomes acquired from PBL do not really match the expected educational outcomes commonly intended and specified for a PBL program. Proficiency in the English language can pose serious problems for some Asian medical schools, which choose to use English as the language for discussion in PBL tutorials. A novel approach that can be applied to overcome this problem is to allow students to engage in discussions using both their native language as well as English, a highly successful practice implemented by the University of Airlangga, Surabaya, Indonesia. As PBL is a highly resource‐intensive pedagogy, Asian medical educators need to have a clear understanding of the PBL process, philosophy and practice in order to be able to optimize the educational outcomes that can be derived from a PBL curriculum.

Summary: 1. The autonomic effects of venoms and toxins from several species of scorpions, including the Indian red scorpion Mesobuthus tamulus, the Chinese scorpion Buthus martensi Karsch and the Israeli scorpion Leiurus quinquestriatus quinquestriatus, all belonging to Buthidae, and the Asian black scorpions Heterometrus longimanus and Heterometrus spinifer, belonging to Scorpionidae, are reviewed.2. The effects of the venoms of M. tamulus and L. q. quinquestriatus on noradrenergic and nitrergic transmission in the rat isolated anococcygeus muscle revealed that both venoms mediated their pharmacological effects via a prejunctional mechanism involving the activation of voltage‐sensitive sodium channels with consequent release of neurotransmitters that mediate target organ responses, similar to the effects mediated by other α‐scorpion toxins.3. Two new toxins, Makatoxin I and Bukatoxin, were purified to homogeneity from the venom of B. martensi Karsch. Determination of their complete amino acid sequences confirmed that both toxins belonged to the class of α‐scorpion toxins. The effects of both toxins on noradrenergic and nitrergic transmission in the rat anococcygeus muscle provided firm evidence that their pharmacological actions also closely resembled those mediated by other α‐scorpion toxins on neuronal voltage‐sensitive sodium channels.4. The venoms of H. longimanus and H. spinifer were found to have high concentrations of noradrenaline (1.8 ± 0.3 mmol/L) and relatively high concentrations of acetylcholine (79.8 ± 1.7 µmol/L) together with noradrenaline (146.7 ± 19.8 µmol/L), respectively, which can account for their potent direct cholinergic and noradrenergic agonist actions in the rat anococcygeus muscle.5. Our studies confirmed that the rat anococcygeus muscle is an excellent nerve–smooth muscle preparation for investigating the effects of bioactive agents on noradrenergic and nitrergic transmission, as well as the direct agonist actions of these agents on post‐synaptic α‐adrenoceptors and M₃ muscarinic cholinoceptors. Although many studies, including our own, have documented that scorpion venoms and toxins mediate their primary effects via a prejunctional mechanism that leads to the marked release of various autonomic neurotransmitters, our studies have shown that there are exceptions to this generally accepted phenomenon. In particular, we have provided firm evidence to show that the venoms from H. longimanus and H. spinifer do not have such a prejunctional site of action but, instead, the venoms mediate their autonomic effects through direct agonist actions on post‐junctional muscarinic M₃ cholinoceptors and α‐adrenoceptors.