Mitochondrial Ribosomal Protein L14 Promotes Cell Growth and Invasion by Modulating Reactive Oxygen Species in Thyroid Cancer

Objectives@#. The mitochondrial ribosomal protein L14 (MRPL14) is encoded by a nuclear gene and participates in mitochondrial protein translation. In this study, we aimed to investigate the role of MRPL14 in thyroid cancer. @*Methods@#. We investigated the association between MRPL14 expression and clinicopathological features using The Cancer Genome Atlas (TCGA) and Chungnam National University Hospital (CNUH) databases. Functional studies of MRPL14, including proliferation, migration, invasion, mitochondrial oxidative phosphorylation and reactive oxygen species (ROS) production, were performed in papillary thyroid cancer (PTC) cell lines (B-CPAP and KTC-1). @*Results@#. Based on the TCGA dataset, PTC tissues lost mitochondrial integrity and showed dysregulated expression of overall mitoribosomal proteins (MRPs) compared with normal thyroid tissues. Of 78 MRPs, MRPL14 was highly expressed in thyroid cancer tissues. MRPL14 overexpression was significantly associated with advanced tumor stage, extrathyroidal extension, and lymph node metastasis. MRPL14 increased cell proliferation of thyroid cancer and promoted cell migration via epithelial-mesenchymal transition-related proteins. Moreover, MRPL14 knockdown reduced the expression of oxidative phosphorylation complex IV (MTCO1) and increased the accumulation of ROS. Cotreatment with a ROS scavenger restored cell proliferation and migration, which had been reduced by MRPL14 knockdown, implying that ROS functions as a key regulator of the oncogenic effects of MRPL14 in thyroid cancer cells. @*Conclusion@#. Our findings indicate that MRPL14 may promote cell growth, migration, and invasion by modulating ROS in thyroid cancer cells.

Does Tutor Evaluation in the PBL Course Assess Different Aspects of Learning from What Written Examination Assesses? / 한국의학교육

PURPOSE: This study was aimed to examine whether tutor evaluation in the PBL course assesses different aspects of learning from what written examination assesses. METHODS: 89 medical students were assessed by Self-Directed Learning Readiness Scale (SDLRS) and Learning Orientation Scale (LOS) in March 2004. Their tutor evaluation and written examination scores in the 1st semester of 2004 PBL units were collected in August 2004. Data analyses were conducted using t-test, correlation analysis, and linear regression. RESULTS: SDLRS scores were significantly correlated with tutor evaluation scores, but not with written examination scores. Both schoolwork orientation and academic orientation scores on LOS were significantly associated with tutor evaluation and written examination scores. Tutor evaluation scores were explained significantly by all predictors, such as SDLRS, schoolwork orientation, and academic orientation scores. However, written examination scores were explained significantly by academic orientation only. CONCLUSIONS: Tutor evaluation in the PBL assessed student self-directed learning readiness and academic orientation, but written examination did not. The findings show a crucial possibility that tutor evaluation may overcome shortcomings of the written examination.

Educational Implication of Peer Evaluation in Problem-based Learning / 한국의학교육

PURPOSE: This study aimed to inquire into the educational implication of peer evaluation in PBL in relation to the evaluation system. METHODS: 89 third and fourth-year medical students in PBL courses participated in this study. Descriptive statistics analysis and correlation analysis were performed. RESULTS: Based on the results of the interviews with all the forth-year students, the feedback method of peer evaluation was modified and the peer evaluation sheet was revised. On the new peer evaluation system, the percentages of indiscriminant scores were significantly lower than those on the previous system. Peer evaluation on the new evaluation system was positively related to tutor evaluation, written examination, and quizzes. Correlations between the peer evaluation scores each units were higher than those of the tutor evaluation scores. All third-year students within the bottom ten percent on the peer evaluation score failed to successfully complete that year. CONCLUSION: The peer evaluation with feedback based on faculty counseling and a user-friendly evaluation sheet can be used as an effective method for assessing student performance in PBL and to screen for maladjusted students.

A Qualitative Evaluation of Problem-Based Learning Curriculum by Students' Perceptions / 한국의학교육

PURPOSE: Recently established in 1997, Sungkyunkwan University School of Medicine was the first medical school in Korea to adopt problem-based learning (PBL) as a core curriculum from the very beginning. The purpose of this study was to evaluate the PBL curriculum from the viewpoint of the medical students. METHODS: This study used a qualitative approach to understand students' perceptions of the positive aspects of PBL. A total of 22 second-year medical students at Sungkynkwan medical school were surveyed. Student perceptions were obtained from questionnaires and face-to-face interviews. The interview was designed to evoke more personal and in-depth responses. RESULTS: Students' perceptions of the effects of PBL were found to be very favorable. Most students showed positive responses on the issues of more active learning attitude, self-directed learning, motivation to study, improved problem solving, and integrated learning. CONCLUSION: The results of this study demonstrated that the students had a good understanding of PBL and experienced its positive aspects of PBL approach. It might be concluded that PBL was successfully implemented into the curriculum and specific and expected effects of PBL accomplished.

The Impact of Application Motives on Medical School Adjustment / 한국의학교육

PURPOSE: This study was aimed to identify application motives and to explore the impact of motives on school adjustment in medical school students. METHODS: Fifty-one third-year medical students were individually interviewed by two independent interviewers to evaluate application motives and school adjustment. Fisher's exact test and two-way analysis of variance were used to examine group differences in school adjustment and academic performance according to application motives and personal characteristics. RESULTS: On the basis of Marcia's identity status model, four types of application motives were identified including "objective orientation", "achievement orientation", "heteronomy" and "objective diffusion." Students who were classified into either objective orientation or achievement orientation did not have any adjustment problem. However, half the students classified into either heteronomy or objective diffusion had academic or social problems. The students in the first two classifications achieved higher grades in basic science courses than those of the later two. Conclusions: These results suggest that application motives tend to impact school adjustment and academic performance. Motive-based admission policies and student guidance should be considered as alternative measure for improving school adjustment and academic performance in medical school students.