• Korean Journal of Radiology
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• v.23 no.9
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• pp.921-930
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• 2022

Objective: To identify epidermal growth factor receptor (EGFR) mutations in lung adenocarcinoma based on ¹⁸F-fluorodeoxyglucose (FDG) PET/CT radiomics and clinical features and to distinguish EGFR exon 19 deletion (19 del) and exon 21 L858R missense (21 L858R) mutations using FDG PET/CT radiomics. Materials and Methods: We retrospectively analyzed 179 patients with lung adenocarcinoma. They were randomly assigned to training (n = 125) and testing (n = 54) cohorts in a 7:3 ratio. A total of 2632 radiomics features were extracted from the tumor region of interest from the PET (1316) and CT (1316) images. Six PET/CT radiomics features that remained after the feature selection step were used to calculate the radiomics model score (rad-score). Subsequently, a combined clinical and radiomics model was constructed based on sex, smoking history, tumor diameter, and rad-score. The performance of the combined model in identifying EGFR mutations was assessed using a receiver operating characteristic (ROC) curve. Furthermore, in a subsample of 99 patients, a PET/CT radiomics model for distinguishing 19 del and 21 L858R EGFR mutational subtypes was established, and its performance was evaluated. Results: The area under the ROC curve (AUROC) and accuracy of the combined clinical and PET/CT radiomics models were 0.882 and 81.6%, respectively, in the training cohort and 0.837 and 74.1%, respectively, in the testing cohort. The AUROC and accuracy of the radiomics model for distinguishing between 19 del and 21 L858R EGFR mutational subtypes were 0.708 and 66.7%, respectively, in the training cohort and 0.652 and 56.7%, respectively, in the testing cohort. Conclusion: The combined clinical and PET/CT radiomics model could identify the EGFR mutational status in lung adenocarcinoma with moderate accuracy. However, distinguishing between EGFR 19 del and 21 L858R mutational subtypes was more challenging using PET/CT radiomics.

• Journal of Yeungnam Medical Science
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• v.41 no.1
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• pp.39-44
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• 2024

Background: Medication-related osteonecrosis of the jaw (MRONJ) is a significant concern, particularly among patients taking bisphosphonates (BPs), denosumab, and selective estrogen receptor modulators (SERMs) for osteoporosis. Despite the known risks, large-scale cohort studies examining the incidence and severity of MRONJ are lacking. We aimed to ascertain the incidence and risk of MRONJ among these patients, whom we stratified by age groups, medication types, and duration of use. Methods: We utilized data from the National Health Insurance Service's sample cohort database, focusing on patients aged 40 years and above diagnosed with osteoporosis. The patients were divided into three groups: those prescribed BPs only, those prescribed SERMs only, and those prescribed both. Results: The overall incidence rate of MRONJ was 0.17%. A significantly higher incidence rate was observed among those taking osteoporosis medications, particularly among females with a relative risk of 4.99 (95% confidence interval, 3.21-7.74). The SERM group also had an incidence rate comparable to that of the BP group. Severity was assessed based on the invasiveness of the treatment methods, with 71.3% undergoing invasive treatment in the medication group. Conclusion: This study provides valuable insights into the incidence and severity of MRONJ among a large cohort of patients with osteoporosis. It underscores the need for comprehensive guidance on MRONJ risks across different medication groups and sets the stage for future research focusing on specific populations and treatment outcomes.

• Annals of Occupational and Environmental Medicine
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• v.35
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• pp.11.1-11.17
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• 2023

Background: Studies on the relationship between organic solvent exposure and chronic kidney disease (CKD) have presented inconsistent results. Definition of CKD has changed in 2012, and other cohort studies have been newly published. Therefore, this study aimed to newly confirm the relationship between organic solvent exposure and CKD through an updated meta-analysis including additional studies. Methods: This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The search was conducted on January 2, 2023 using Embase and MEDLINE databases. Case-control and cohort studies on the relationship between organic solvent exposure and CKD were included. Two authors independently reviewed full-text. Results: Of 5,109 studies identified, a total of 19 studies (control studies: 14 and cohort studies: 5) were finally included in our meta-analysis. The pooled risk of CKD in the organic solvent exposed group was 2.44 (1.72-3.47). The risk of a low-level exposure group was 1.07 (0.77-1.49). The total risk of a high-level exposure group was 2.44 (1.19-5.00). The risk of glomerulonephritis was 2.69 (1.18-6.11). The risk was 1.46 (1.29-1.64) for worsening of renal function. The pooled risk was 2.41 (1.57-3.70) in case-control studies and 2.51 (1.34-4.70) in cohort studies. The risk of subgroup classified as 'good' by the Newcastle Ottawa scale score was 1.93 (1.43-2.61). Conclusions: This study confirmed that the risk of CKD was significantly increased in workers exposed to mixed organic solvents. Further research is needed to determine the exact mechanisms and thresholds. Surveillance for kidney damage in the group exposed to high levels of organic solvents should be conducted.

• Korean Journal of Social Welfare
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• v.60 no.2
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• pp.53-76
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• 2008

This study analyze the intergenerational transmission of poverty in Korea, using the first wave of Korea Welfare Panel Study. For this analysis, I produced poverty transition tables across generation and estimated logistic models to explore the effects of parent's poverty on the children's adulthood poverty. As the results, I found that parent's poverty reduced children's education level and then the low education level increased the likelihood that children experience poverty in their adulthood. In other words, parent's poverty might increase children's adulthood poverty through the mediating effects of education level. This mediating effects were also identified in the analyses by group and cohort. From the analyses by group, daughters rather than sons, those from urban rather than rural area, and the older cohort rather than younger cohort showed greater intergenerational transmission of poverty.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.9
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• pp.4713-4717
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• 2012

Objectives: This systematic review of cohort studies aimed to identify any association between specific dietary patterns and risk of colorectal cancer (CRC). Dietary patterns involve complex interactions of food and nutrients summarizing the total diet or key aspects of the diet for a population under study. Methods and materials: This review involves 6 cohort studies of dietary patterns and their association with colorectal cancer. An exploratory or a posteriori approach and a hypothesis-oriented or a priori approach were employed to identify dietary patterns. Results: The dietary pattern identified to be protective against CRC was healthy, prudent, fruits and vegetables, fat reduced/diet foods, vegetables/fish/poultry, fruit/wholegrain/dairy, healthy eating index 2005, alternate healthy eating index, Mediterranean score and recommended food score. An elevated risk of CRC was associated with Western diet, pork processed meat, potatoes, traditional meat eating, and refined grain pattern. Conclusion: The Western dietary pattern which mainly consists of red and processed meat and refined grains is associated with an elevated risk of development of CRC. Protective factors against CRC include a healthy or prudent diet, consisting of vegetables, fruits, fish and poultry.

• Journal of Ecology and Environment
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• v.31 no.3
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• pp.207-211
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• 2008

We investigated the leaf demography of a temperate woody liana, Akebia trifoliata, in a temperate forest in Japan, Akebia is semi-evergreen: some leaves are shed before winter, while others remain through the winter. Previous studies of semi-evergreen species found that variation in leaf life span was caused by variation in the timing of leaf emergence, Leaves that appeared just before winter over-wintered, while leaves appearing earlier were shed, However, it is unclear whether leaves of the same cohort (i.e., leaves that appear at the same time within a single site) show variation in life span under the effect of strong seasonality. To separate variation in life span among the leaves in each cohort from variation among cohorts, we propose a new method - the single leaf diagram, which shows the emergence and death of each leaf. Using single leaf diagrams, our study revealed that Akebia leaves within a cohort showed substantial variation in life span, with some over-wintering and some not. In addition, leaves on small ramets in the understory showed great variation in life span, while leaves on large ramets, which typically reach higher positions in the forest canopy, have shorter lives, As a result, small ramets were semi-evergreen, whereas large ramets were deciduous, The longer lives of leaves on small ramets can be interpreted as a shade-adaptive strategy in understory plants.

• Journal of the Korean Society of Clothing and Textiles
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• v.38 no.1
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• pp.33-45
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• 2014

This study investigates urban household consumption patterns for clothing items in different income cohorts through the analysis of an Almost Ideal Demand System (AIDS) model. Korea quarterly time-series statistics data for urban household expenditures from 1990 to 2013 analyzed household demand. The price and total consumption expenditure elasticities of 4 clothing items (outer wear, shoes, clothing related services and other miscellaneous clothing) for 7 income cohorts were estimated to investigate the clothing consumption patterns of different income cohorts. The study results show that the different household income cohorts have different consumption patterns for clothing items. The elastic demand of total consumption expenditures in the lowest household income cohort suggests that they consume clothing items as luxuries while other households mostly consume them as necessities. The price elasticity for all household income cohorts and clothing items (except the highest household income cohort and outer wear) was found to be elastic. The highest household income cohort had an inelastic price demand for all clothing items that implied a less sensitive clothing consumption change for the clothing price change than other households.

• Health Policy and Management
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• v.25 no.4
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• pp.253-255
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• 2015

The concept of precision medicine-prevention and treatment strategies that take individual variability into account-is hot issue of US in the year 2015. Precision medicine is a new concept that approach patients individually by there characteristics, such as genome, life style, environmental exposure, etc. For developing the precision medicine, National Institute of Health of US has been prepared the Precision Medicine Initiative Cohort Program, at least 1 million people cohort. The US President Obama announced the Precision Medicine Initiative on 30th January 2015. He announced that he will pioneer a new model of patient-powered research that promises to accelerate biomedical discoveries and provide clinicians with new tools, knowledge, and therapies to select which treatments will work best for which patients. Most medical treatments have been designed for the 'average patient.' As a result of this 'one-size-fits-all-approach,' treatments can be very successful for some patients but not for others. This is changing with the emergence of precision medicine, an innovative approach to disease prevention and treatment that takes into account individual differences in people's genes, environments, and lifestyles. Precision medicine gives clinicians tools to better understand the complex mechanisms underlying a patient's health, disease, or condition, and to better predict which treatments will be most effective. The healthcare researcher should prepare the new medicine era such as bio-information technology convergence, big data study.

• Journal of the Korean Society of Food Culture
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• v.17 no.4
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• pp.435-445
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• 2002

The purpose of this study was to identify the pattern and perception of food consumption, mass restaurant use, drinking style, and food purchasing factors by cohort groups i. e., World Cup(W) generation, baby boom, and silent generation. Data were collected from 412 respondents including three generations by questionnaire method in April through May 2002. Analysis of variance and chi-square results indicate that there were significant differences among three generation groups for the pattern and perception of food consumption, the use of mass restaurant, preferred drinking style, and influencing factors for food purchasing. W generation are more likely to be influenced by sensibility factor than baby boom and silent generation. Considering food preference pattern, baby boom as well as silent generation prefer green vegetables than meats, and they must have Kimche when having meals. Similarities and differences in perceptional pattern types are discussed, and future implications for food and nutrition specialists and food marketers are provided.

• Journal of the Korean housing association
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• v.22 no.1
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• pp.11-23
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• 2011

The purpose of this study is to explore cohort changes in first-time homeownership in Korea. The study collected qualitative data from individual interviews to explore the housing trajectories of different birth cohorts. As a result, Individual interviews facilitated an exploration of the decision making process of first-time homeowner with in a cohort context. The cohorts born in the 1950s seek a sense of security through homeownership, and have strong Korean sentiments of ownership. They tried various means to buy a house, and real estate market boom at that time played a role in the driving force. The cohorts born in the 1960s have less insecurity of tenure than the previous cohorts, but they still feel the need for homeownership. Since the currency crisis in 1997 caused the fluctuation of housing price, the 1960s cohort experienced a dramatic decline and rebound of assets while the previous cohorts had experienced a steady rise in housing prices. Finally, the attitude towards housing in the group of 1970s cohorts has changed from ownershiporiented to use-oriented.