INTRODUCTIONProblem-based learning (PBL) embraces principles of good learning and teaching. It is student-directed, fosters intrinsic motivation, promotes active learning, encourages peer teaching, involves timely feedback, and can support student self and peer assessment. The most important function of the assessment process is to enhance student learning, to improve the curriculum and to improve teaching.

MATERIALS AND METHODSTo improve the PBL tutorial in Chung Shan Medical University, we developed an online evaluation system containing the evaluation forms for students, tutor, self and peer. The Cronbach alpha reliability coefficients were 0.9480, 0.9103, and 0.9198 for the Student, Tutor and Self and Peer Evaluation Form, respectively. The online evaluations were mandatory to both students and tutors, and the information was completely anonymous.

RESULTS AND CONCLUSIONSThe survey response rates of the online evaluations ranged from 95.6% to 100%. The online evaluations provided a documented feedback to the students on their knowledge, skills and attitudes. Correspondingly, tutors too received feedback from students in evaluating their performance on the appropriateness and effectiveness of tutoring the group. Although there was an initial lack of coordination regarding responsibilities and how to use the online system for both students and the Faculty, the system enabled us to look into how effective our PBL course had been, and it provided both process and outcome evaluations. Our strategy for evaluating the success of PBL is only at its initial stage; we are in an ongoing process of collecting outcome data for further analysis which will hopefully provide more constructive information to the PBL curricula.

Education, Medical ; standards ; Educational Measurement ; Humans ; Online Systems ; Pilot Projects ; Problem-Based Learning ; methods ; Taiwan ; Universities

Ornithine decarboxylase (ODC) is the rate-limiting enzyme in polyamine biosynthesis and a target for chemoprevention. Hydroxydibenzoylmethane (HDB), a derivative of dibenzoylmethane of licorice, is a promising chemopreventive agent. In this paper, we investigated whether HDB would inhibit the ODC pathway to enhance apoptosis in human promyelocytic leukemia HL-60 cells. We found ODC enzyme activity was reduced during HDB treatment. Overexpression of ODC in HL-60 parental cells could reduce HDB-induced apoptosis, which leads to loss of mitochondrial membrane potential (Deltapsim), through lessening intracellular ROS. Furthermore, ODC overexpression protected cytochrome c release and the activation of caspase-3 following HDB treatment. The results demonstrated HDB-induced apoptosis was through a mechanism of down-regulation of ODC and occurred along a ROS-dependent mitochondria-mediated pathway.
Apoptosis/*drug effects ; Caspase 3/metabolism ; Chalcones/metabolism/*pharmacology ; Chemoprevention ; Cytochromes c/biosynthesis/secretion ; Down-Regulation ; Gene Expression ; HL-60 Cells ; Humans ; Immunoblotting ; Leukemia, Myeloid/*enzymology/pathology ; Membrane Potential, Mitochondrial/drug effects ; Mitochondria/enzymology ; Ornithine Decarboxylase/antagonists & inhibitors/genetics/*metabolism ; Reactive Oxygen Species/analysis/metabolism ; Reverse Transcriptase Polymerase Chain Reaction

Inflammation alters the neural stem cell (NSC) lineage from neuronal to astrogliogenesis. However, the underlying mechanism is elusive. Autophagy contributes to the decline in adult hippocampal neurogenesis under E. coli lipopolysaccharide (LPS) stimulation. SRY-box transcription Factor 2 (SOX2) is critical for NSC self-renewal and proliferation. In this study, we investigated the role of SOX2 in induced autophagy and hippocampal adult neurogenesis under LPS stimulation. LPS (5 ng•100 g -1 •hour -1 for 7 days) was intraperitoneally infused into male Sprague–Dawley rats (8 weeks old) to induce mild systemic inflammation. Beclin 1 and autophagy protein 12 (Atg12) were significantly upregulated concurrent with decreased numbers of Ki67- and doublecortin (DCX)-positive cells in the dentate gyrus. Synchronically, the levels of phospho(p)-mTOR, the p-mTOR/mTOR ratio, p-P85s6k, and the p-P85s6k/P85s6k ratio were suppressed. In contrast, SOX2 expression was increased. The fluorescence micrographs indicated that the colocalization of Beclin 1 and SOX2 was increased in the subgranular zone (SGZ) of the dentate gyrus. Moreover, increased S100β-positive astrocytes were colocalized with SOX2 in the SGZ. Intracerebroventricular infusion of 3-methyladenine (an autophagy inhibitor) effectively prevented the increases in Beclin 1, Atg12, and SOX2. The SOX2 + -Beclin 1 + and SOX2 + -S100β + cells were reduced. The levels of p-mTOR and p-P85s6k were enhanced. Most importantly, the number of DCX-positive cells was preserved. Altogether, these data suggest that LPS induced autophagy to inactivate the mTOR/P85s6k pathway, resulting in a decline in neural differentiation. SOX2 was upregulated to facilitate the NSC lineage, while the autophagy milieu could switch the SOX2-induced NSC lineage from neurogenesis to astrogliogenesis.

INTRODUCTIONProblem-based learning (PBL), a pedagogic concept using a student-centred approach and problem-solving through small group discussions, has been adopted in varying degrees for years at all 11 medical institutes in Taiwan. Much evidence has shown that a number of factors can seriously affect student performance in PBL courses, such as the design of PBL scenarios, the tutors' character and students' attitudes and efforts.

MATERIALS AND METHODSThe aim of this study was to examine how the personal characters or knowledge base of Taiwanese medical students influence their performance in a hybrid-PBL curriculum. A total of 309 (234 male, 75 female) high-school entry undergraduate medical students participated in this survey. Self-assessed personal traits were presented in a 44-item questionnaire with a Big Five factor structure. Knowledge base was assessed by students' score point average (SPA) based on their previous 4-year education in medical school. Peer-assessed performance of students in the PBL curriculum was carried out using a well-developed, reliable and validated evaluation form.

RESULTSEach student's peer-evaluated PBL performance can be divided into 5 principal components, which included control-lead, assist-coordinate, written organisation and compromise- comply (Eigen value >1). The consistency and reliability of the Big Five questionnaire on personal traits was analysed and discordant items were deleted (Cronbach's alpha = 0.72 to 0.86 after deletion). The relationship between the personal traits, knowledge base and PBL performance, as analysed by simple regression, showed that "extraversion" and "openness to experience" were positively related to the "assist-coordinate" characteristic in PBL performance, and "conscientiousness" was positively related to the "control-lead" characteristic in PBL performance. The SPA was positively related to the "assist-coordinate" or "control-lead" characteristic in PBL performance. The "agreeableness" was negatively correlated with the "control-lead" characteristic in PBL performance. After stepwise regression between the Big Five and each component of PBL performance, only the correlation between conscientiousness and control/lead, and between extraversion and assist/coordinate remained significant.

CONCLUSIONKnowledge and personality characteristics appear to be associated with student performance in a hybrid-PBL curriculum. The implications of this study on the future development and application of this assessment tool in medical schools are presented.

Educational Measurement ; Female ; Humans ; Male ; Mental Competency ; psychology ; Problem-Based Learning ; methods ; Retrospective Studies ; Students, Medical ; psychology ; Surveys and Questionnaires ; Taiwan

Purpose: Biomarkers predicting clinically significant prostate cancer (sPC) before biopsy are currently lacking. This study aimed to develop a non-invasive urine test to predict sPC in at-risk men using urinary metabolomic profiles. Materials and Methods: Urine samples from 934 at-risk subjects and 268 treatment-naïve PC patients were subjected to liquid chromatography/mass spectrophotometry (LC-MS)-based metabolomics profiling using both C18 and hydrophilic interaction liquid chromatography (HILIC) column analyses. Four models were constructed (training cohort [n=647]) and validated (validation cohort [n=344]) for different purposes. Model I differentiates PC from benign cases. Models II, III, and a Gleason score model (model GS) predict sPC that is defined as National Comprehensive Cancer Network (NCCN)-categorized favorable-intermediate risk group or higher (Model II), unfavorable-intermediate risk group or higher (Model III), and GS ≥7 PC (model GS), respectively. The metabolomic panels and predicting models were constructed using logistic regression and Akaike information criterion. Results: The best metabolomic panels from the HILIC column include 25, 27, 28 and 26 metabolites in Models I, II, III, and GS, respectively, with area under the curve (AUC) values ranging between 0.82 and 0.91 in the training cohort and between 0.77 and 0.86 in the validation cohort. The combination of the metabolomic panels and five baseline clinical factors that include serum prostate-specific antigen, age, family history of PC, previously negative biopsy, and abnormal digital rectal examination results significantly increased AUCs (range 0.88–0.91). At 90% sensitivity (validation cohort), 33%, 34%, 41%, and 36% of unnecessary biopsies were avoided in Models I, II, III, and GS, respectively. The above results were successfully validated using LC-MS with the C18 column. Conclusions Urinary metabolomic profiles with baseline clinical factors may accurately predict sPC in men with elevated risk before biopsy.