BACKGROUND: As Korea advances into the ageing society, the number of elderly person receiving dialysis has increased. Two-year survival rate of the patients who received hemodialysis was 84.2% in 1996. But there is no estimate on the survival rate of the patients over age 65. Elderly persons are more prone to have dialysis complications and have more problems in cardiovascular system. The following is a 5-year-study on the elderly ESRD patients who underwent hemodialysis. METHODS: In this retrospective study, 825 patients had received hemodialysis at Seoul Paik Hospital from Jan. 1997 to Dec. 2002. The elderly group was consisted of 35 patients over age 65 and the non-elderly group was consisted of 43 patients below age 65 who received hemodialysis. And they had been traced for more than six months. The patient`s age, sex, occupation and whether the patient was married or not, had been compiled. Also taken into consideration was etiology, complications, initial laboratory data, electrocardiography, abdominal sonography, echocardiography, ftmndus examination, cause of death. RESULTS: Average age of the elderly and the non-elderly group was 70.1 and 47.4 years(p<0.00). nd parathyroid hormone were different between the two groups(p<0.05), other laboratory data were not. Prevalence of diabetes mellitus and hypertensive nephrosclerosis were not either. The overall 1, 2, 5 year survival rate was 97.3%, 93.4%, 73.7%. And the 5-year survival rate was 88.6% in the non-elderly group and it was 54.1% in the elderly group(Kaplan-Meier method). Causes of death were sepsis(n=3), cerebrovas cular accident(n=2), myocardial infarction, pneumonia and gastrointestinal bleeding, malignancy, withdrawal of treatment(1 patient respectively) in the elderly group and were myocardial infarction, withdrawal of treatment in the non-elderly group(n=2). CONCLUSION: The 5-year survival rate of the elderly patients was lower than the non-elderly(p<0.001). The contributing factor of death was not etiology but cormobid condition according to ageing process and socioeconomic circumstance. In other words, it was cardiovascular disease, infection due to impaired immune system and withdrawal of treatment due to economic problems. So it would be necessary to monitor carefully these factors for the elderly hemodialysis patients to improve survival..
Aged* ; Cardiovascular Diseases ; Cardiovascular System ; Cause of Death ; Diabetes Mellitus ; Dialysis ; Echocardiography ; Electrocardiography ; Hemorrhage ; Humans ; Immune System ; Kidney Failure, Chronic ; Korea ; Myocardial Infarction ; Nephrosclerosis ; Occupations ; Parathyroid Hormone ; Pneumonia ; Prevalence ; Renal Dialysis* ; Retrospective Studies ; Seoul ; Survival Rate

The extracellular matrix (ECM) is a heterogeneous, connective network composed of fibrous glycoproteins that coordinate in vivo to provide the physical scaffolding, mechanical stability, and biochemical cues necessary for tissue morphogenesis and homeostasis. This review highlights some of the recently raised aspects of the roles of the ECM as related to the fields of biophysics and biomedical engineering. Fundamental aspects of focus include the role of the ECM as a basic cellular structure, for novel spontaneous network formation, as an ideal scaffold in tissue engineering, and its essential contribution to cell sheet technology. As these technologies move from the laboratory to clinical practice, they are bound to shape the vast field of tissue engineering for medical transplantations.
Biomedical Engineering ; Biophysics ; Cellular Structures ; Collagen ; Cues ; Elastin ; Extracellular Matrix* ; Fibronectins ; Glycoproteins ; Homeostasis ; Morphogenesis ; Tissue Engineering*

In this article, the 3rd author's name was misprinted unintentionally. The name should be corrected from 'Ik Keun Kwon' to 'Il Keun Kwon'.

The purpose of this study was to examine the chronological changes and progress in medical education research in Korea and to identify the less investigated topics that need further study and improvement with regard to methodological quality. Of the 590 articles that were published from 1989 to 2010 in the Korean Journal of Medical Education, 386 original research papers were extracted for the analysis. The extracted papers were systematically reviewed using 2 analysis schemes that we developed: one scheme was designed to classify research topics, and the other determined the methodology that was used. The main results were as follows: The most popular research areas were curriculum, educational method, and evaluation in basic medical education; in contrast, studies that addressed postgraduate education, continuous professional development, and educational administration were less frequent; The most frequently studied topics were clinical performance/skills evaluation, clerkship, curriculum development, and problem-based learning, Quantitative studies predominated over qualitative studies and mixed methods (265 vs. 95 vs. 26). Two hundred forty papers were descriptive, cross-sectional studies, and 17 were experimental studies. Most qualitative studies were non-participation observational studies. In conclusion, there has been dramatic growth in the extent of medical education research in Korea in the past two decades. However, more studies that investigate the graduate medical education and the continuous professional development should be performed. Moreover, robust experimental designs and methods should be applied to provide stronger evidence that can practice best-evidence medical education.
Cross-Sectional Studies ; Curriculum ; Education, Medical ; Education, Medical, Graduate ; Korea ; Problem-Based Learning ; Research Design

Purpose: Pulmonary sarcomatoid carcinoma (PSC) is a rare aggressive subtype of non–small cell lung cancer (NSCLC) with limited therapeutic strategies. We attempted to elucidate the evolutionary trajectories of PSC using multiregional and longitudinal tumor samples. Materials and Methods: A total of 31 patients were enrolled in this study and 11 longitudinal samples were available from them. Using whole exome sequencing data, we analyzed the mutational signatures in both carcinomatous and sarcomatous areas in primary tumors of the 31 patients and longitudinal samples obtained from 11 patients. Furthermore, digital droplet polymerase chain reaction (ddPCR), and programmed death-ligand 1 (PD-L1) immunohistochemistry using the Ventana SP263 assay were performed. Results: TP53 was identified as the most frequently altered gene in the primary (74%) and metastatic (73%) samples. MET exon 14 skipping mutations, confirmed by ddPCR, and TP53 mutations were mutually exclusive; whereas, MET exon 14 skipping mutations frequently co-occurred with MDM2 amplification. Metastatic tumors showed dissimilar genetic profiles from either primary component. During metastasis, the signatures of APOBEC decreased in metastatic lesions compared with that in primary lesions. PSC showed higher MET and KEAP1 mutations and stronger PD-L1 protein expression compared with that recorded in other NSCLCs. Conclusion Decreased APOBEC signatures and subclonal diversity were detected during malignant progression in PSC. Frequent MET mutations and strong PD-L1 expression distinguished PSC from other NSCLCs. The aggressiveness and therapeutic difficulties of PSC were possibly attributable to profound intratumoral and intertumoral genetic diversity. Next-generation sequencing could suggest the appropriate treatment strategy for PSC.

Background: Hepatocellular carcinoma (HCC) is the second-most-common cause of cancer-related deaths worldwide, and an accurate and non-invasive biomarker for the early detection and monitoring of HCC is required. We assessed pathogenic variants of HCC driver genes in cell-free DNA (cfDNA) from HCC patients who had not undergone systemic therapy. Methods: Plasma cfDNA was collected from 20 HCC patients, and deep sequencing was performed using a customized cfDNA next-generation sequencing panel, targeting the major HCC driver genes (TP53, CTNNB1, TERT) that incorporates molecular barcoding. Results: In 13/20 (65%) patients, we identified at least one pathogenic variant of two major HCC driver genes (TP53 and CTNNB1), including 16 variants of TP53 and nine variants of CTNNB1. The TP53 and CTNNB1 variants showed low allele frequencies, with median values of 0.17% (range: 0.06%–6.99%) and 0.07% (range: 0.05%–0.96%), respectively. However, the molecular coverage of variants was sufficient, with median values of 5,543 (range: 2,317–9,088) and 7,568 (range: 2,400–9,633) for TP53 and CTNNB1 variants, respectively. Conclusions Our targeted DNA sequencing successfully identified low-frequency pathogenic variants in the cfDNA from HCC patients by achieving high coverage of unique molecular families. Our results support the utility of cfDNA analysis to identify somatic gene variants in HCC patients.

BACKGROUND: The aim of the study is the development of nutrition education program for promoting vegetable intakes of school aged children. METHODS: After a pilot study and consultations of experts, a program (composed of five lessons) that was emphasized the sensory and cooking activities based on the social cognitive theory was developed. Specially, we focused on enhance expectation, self-efficacy, and behavioral performance through the intervention. For a outcome evaluation survey tool was developed, too. The lessons once-a-week (total five lessons) and survey (pre and pro) were conducted to 20 school aged children. RESULTS: The distribution of children was 11.5 years (mean age), boys (25%), girls (75%). Compared to pre-survey, the result of post-survey was higher scores for self-efficacy and two items out of ten items in food neophobia category. And one items out of six items (unfamiliar vegetables), three items out of ten items (familiar vegetables) showed positive result in food neophilia category significantly (P<0.1). CONCLUSIONS: The education duration was short(5 weeks) but we could observe visible changes on self-efficacy, behavior performances for cooking and intention to intake vegetables non-preferred ones previously. Continuous applying and supplementing this nutrition education program may promote intake of vegetables among children.
Child ; Cooking ; Education ; Female ; Humans ; Intention ; Pilot Projects ; Referral and Consultation ; Vegetables

OBJECTIVES: An association between dietary patterns and mental health in children has been suggested in a series of studies, yet detailed analyses of dietary patterns and their effects on ADHD (attention deficit hyperactivity disorder) are limited. METHODS: We included 4569 children who had dietary intake data as part of the CHEER (Children's Health and Environmental Research) study conducted nationwide from 2005 to 2010. We assessed ADHD (Attention Deficit Hyperactivity Disorder) by the DuPaul's ADHD Rating Scales and dietary intake by a semi-quantitative food frequency questionnaire. Using intake data, we constructed five dietary patterns: “Plant foods & fish,” “Sweets,” “Meat & fish,” “Fruits & dairy products,” and “Wheat based.” RESULTS: The overall proportion of ADHD was 12.3%. Boys (17.8%) showed a higher rate of ADHD than girls (6.5%). The total intake of calories (85 kcal) and plant fat (2g) in the ADHD group was significantly higher than that of the normal group. ADHD was significantly negatively associated with dietary habits such as having breakfast and meal frequency, and positively associated with eating speed, unbalanced diet, overeating, and rice consumption. Regarding dietary patterns, the “Sweets” category was relevant to high ADHD risk (OR 1.59, 95% CI: 1.18, 2.15 for Q5 vs. Q1) in a linear relationship. An inverse, non-linear association was found between “Fruits & dairy products” and ADHD (OR 0.55, 95% CI: 0.39, 0.76 for Q4 vs. Q1). CONCLUSIONS: Our study confirms both positive and negative associations between diet and ADHD in elementary school age children. Moreover, linear or nonlinear associations between diet and ADHD draw attention to the possible threshold role of nutrients. Further studies may consider characteristics of diet in more detail to develop better intervention or management in terms of diet and health.
Attention Deficit Disorder with Hyperactivity ; Breakfast ; Child ; Diet ; Eating ; Female ; Food Habits ; Humans ; Hyperphagia ; Meals ; Mental Health ; Plants ; Weights and Measures

No abstract available.
Adenocarcinoma

BACKGROUND: Both human leukocyte antigen (HLA) class I and programmed death-ligand 1 (PD-L1) molecules are known to play important roles in cancer immunity. In this study, we evaluated HLA class I expression in resected adenocarcinoma of the lung, and investigated its prognostic impact in correlation with PD-L1 expression. METHODS: HLA class I and PD-L1 expression was evaluated by immunohistochemistry in a total of 403 resected lung adenocarcinomas using tissue microarray. Correlations between the expression of HLA class I/PD-L1 and clinicopathologic features and prognostic significance were analyzed. RESULTS: HLA class I expression was reduced in 91.6% of adenocarcinoma, and more frequently reduced in patients with younger age, absence of vascular invasion, and low pathologic stage (p = .033, p = .007, and p = .012, respectively). Positive PD-L1 expression in tumor cells was 16.1% (1% cut-off), and associated with poor differentiation, presence of vascular invasion and nodal metastasis (p < .001, p = .002, and p = .032, respectively). On survival analysis, HLA class I or PD-L1 expression alone did not show any statistical significance. On the integrated analysis, HLA class I (+)/PD-L1 (+) subgroup showed a significantly shorter overall survival than other groups (p = .001). Multivariate analysis revealed that coexpression of HLA class I and PD-L1 was an independent poor prognostic factor of lung adenocarcinoma. (p < .001; hazard ratio, 6.106; 95% confidence interval, 2.260 to 16.501). CONCLUSIONS: Lung adenocarcinoma with coexpression of HLA class I and PD-L1 was associated with poor prognosis. This subgroup may evade immune attack by expressing PD-L1 protein despite HLA expression.
Adenocarcinoma ; Carcinoma, Non-Small-Cell Lung ; Humans ; Immunohistochemistry ; Leukocytes ; Lung ; Multivariate Analysis ; Neoplasm Metastasis ; Prognosis