Purpose: Here we aimed to examine the association of breastfeeding (BF) with the metabolic syndrome (Mets) and its components among premenopausal parous Korean women. Methods: We conducted a cross-sectional study on 7,116 Korean women by using nationally representa tive data from the Korea National Health and Nutrition Examination Survey, between 2010 and 2016. Mul­tivariate logistic regression analysis was performed for examining the association of BF with Mets and its components. Results: A total 7,116 women were selected for this study. Mets was present in 12.9% of the study parti cipants. The prevalence of Mets in the BF group (12.38%) was lower than that of the non-BF group (14.69 %) (p<0.05). The prevalence of hypertension and hypertriglyceridemia was significantly higher in the non-BF group compared to that of the BF group. For each of Mets components, the total cholestrol level and systolic blood pressure were significantly higher in the non-BF group, compared to those of the BF group (p<0.05). The BF group was associated with a decreased risk of Mets (odds ratio [OR], 0.82; 95% confidence interval [CI], 0.68–0.99). and lower risks of hypo-high-density lipoprotein-cholesterolemia (OR, 0.78; 95% CI, 0.62–0.68), compared to those of the non-BF group. Conclusion BF is an important factor in reducing the risks of Mets. These results provide fundamental evidence for the establishment of policies for promoting BF.

It is interested in examining treatment effect on a particular category of subjects or in comparing treatment effects among different subgroups as well as overall treatment effect due to heterogeneity of study subjects. Subgroup analyses are exceedingly common, but they are also often misleading. Conclusions based on subgroup analyses can do harm both when a particular category of people is denied effective treatment (a "false-negative" conclusion), and when ineffective or even harmful treatment is given to a subgroup of people (a "false-positive" conclusion). Because of the frequency and the importance of clinical application of subgroup analysis, researchers need to be cautious about doing subgroup analyses. This study presents guidelines to help conducting subgroup analyses correctly.
Population Characteristics

Confounding is the distortion of a disease/exposure association brought about by other factors which are not considered in the study design or the data analysis. These factors are called confounding factors. We should be cautious in data analysis of observational study of association of disease/exposure, since confounding often occurred in observational study. This study examines confounding effect according to data pattern (the ratio of controls to cases, the ratio of exposures to non-exposures for each level of confounding factor), criteria for treating a variable as a confounding variable, and some notes for the analysis in case-control study.
Case-Control Studies* ; Confounding Factors (Epidemiology) ; Observational Study ; Statistics as Topic

Purpose: The living arrangements of elderly persons can play a crucial role in their health.This study evaluated the association between living arrangements and frailty among elderly Korean men. Methods: The cross-sectional data from the Korea National Health and Nutrition Examination Survey (2014–2019) were used. A total of 3,198 men aged 65 years or older were divided into a living alone group (LA, n = 393) and a not living alone group (NLA, n = 2,805). The dietary intake data was obtained from a single 24-hour recall. The food variety score (FVS) was defined as the number of foods items consumed in one day. Frailty was defined as the presence of three or more of the modified Fried frailty phenotype criteria. The association between living arrangements and frailty was analyzed by multiple nominal logistic regression. Results: The LA group showed significantly lower FVSs than the NLA group. The intakes of fruit, vegetables, fish and shellfish, fiber, and key antioxidant nutrients such as vitamins A and C, were lower in LA than in NLA. Multiple nominal logistic regression revealed a higher odds ratio (OR) for frailty in the LA group compared to the NLA group (OR [95% confidence interval], 2.05 [1.12–3.74]; p = 0.019). Conclusion These findings suggest that the increased risk of frailty among elderly men living alone may be partially associated with their lower dietary variety, particularly reduced intake of essential nutrients from fruit, vegetables, fish, and shellfish, highlighting their vulnerability to suboptimal nutrition. Thus, increasing diversity in food intake could be a useful dietary strategy to prevent the frailty of the living alone elderly.

Purpose: The living arrangements of elderly persons can play a crucial role in their health.This study evaluated the association between living arrangements and frailty among elderly Korean men. Methods: The cross-sectional data from the Korea National Health and Nutrition Examination Survey (2014–2019) were used. A total of 3,198 men aged 65 years or older were divided into a living alone group (LA, n = 393) and a not living alone group (NLA, n = 2,805). The dietary intake data was obtained from a single 24-hour recall. The food variety score (FVS) was defined as the number of foods items consumed in one day. Frailty was defined as the presence of three or more of the modified Fried frailty phenotype criteria. The association between living arrangements and frailty was analyzed by multiple nominal logistic regression. Results: The LA group showed significantly lower FVSs than the NLA group. The intakes of fruit, vegetables, fish and shellfish, fiber, and key antioxidant nutrients such as vitamins A and C, were lower in LA than in NLA. Multiple nominal logistic regression revealed a higher odds ratio (OR) for frailty in the LA group compared to the NLA group (OR [95% confidence interval], 2.05 [1.12–3.74]; p = 0.019). Conclusion These findings suggest that the increased risk of frailty among elderly men living alone may be partially associated with their lower dietary variety, particularly reduced intake of essential nutrients from fruit, vegetables, fish, and shellfish, highlighting their vulnerability to suboptimal nutrition. Thus, increasing diversity in food intake could be a useful dietary strategy to prevent the frailty of the living alone elderly.

Purpose: The living arrangements of elderly persons can play a crucial role in their health.This study evaluated the association between living arrangements and frailty among elderly Korean men. Methods: The cross-sectional data from the Korea National Health and Nutrition Examination Survey (2014–2019) were used. A total of 3,198 men aged 65 years or older were divided into a living alone group (LA, n = 393) and a not living alone group (NLA, n = 2,805). The dietary intake data was obtained from a single 24-hour recall. The food variety score (FVS) was defined as the number of foods items consumed in one day. Frailty was defined as the presence of three or more of the modified Fried frailty phenotype criteria. The association between living arrangements and frailty was analyzed by multiple nominal logistic regression. Results: The LA group showed significantly lower FVSs than the NLA group. The intakes of fruit, vegetables, fish and shellfish, fiber, and key antioxidant nutrients such as vitamins A and C, were lower in LA than in NLA. Multiple nominal logistic regression revealed a higher odds ratio (OR) for frailty in the LA group compared to the NLA group (OR [95% confidence interval], 2.05 [1.12–3.74]; p = 0.019). Conclusion These findings suggest that the increased risk of frailty among elderly men living alone may be partially associated with their lower dietary variety, particularly reduced intake of essential nutrients from fruit, vegetables, fish, and shellfish, highlighting their vulnerability to suboptimal nutrition. Thus, increasing diversity in food intake could be a useful dietary strategy to prevent the frailty of the living alone elderly.

PURPOSE: The purpose of the present retrospective cohort study was to investigate the incidence of sinus perforation during endodontic microsurgery and to assess healing of cases with sinus perforation. MATERIALS AND METHODS: Clinical and radiographic records were collected from patients who were treated with endodontic microsurgery in the Microscope Center of the Department of Conservative Dentistry at Yonsei University College of Dentistry, Seoul, Korea, between March 2001 and January 2016. To determine the incidence of sinus perforation, all cases involving maxillary premolar and molar teeth were assessed, and cases with perforation of maxillary sinus during the procedure were counted. To assess the outcome of the endodontic microsurgery, cases with sinus perforation were recalled at least 1 year after surgery. RESULT: Two hundred and forty-nine maxillary premolars and molars were treated with endodontic microsurgery. Among these cases, 16 cases had sinus perforations. Overall incidence of sinus perforation was 6.4%. Thirteen cases with sinus perforation were followed up for 1 year after endodontic microsurgery. Outcome assessment revealed that 2 of 13 cases with sinus perforation had failed. The success rate of endodontic microsurgery with sinus perforation was 84.6%. CONCLUSION: Endodontic surgery performed using microsurgical techniques decreases the risk of sinus perforation. Predictable outcomes of endodontic microsurgeries and healing of sinus membrane can be expected with adequate treatment steps and careful periodic follow-ups in cases with maxillary sinus perforations.
Bicuspid ; Cohort Studies ; Dentistry ; Follow-Up Studies ; Humans ; Incidence ; Korea ; Maxillary Sinus* ; Membranes ; Microsurgery* ; Molar ; Retrospective Studies ; Seoul ; Tooth

PURPOSE: As comprehensive nursing care service has gradually expanded, it has become necessary to explore the various opinions about it. The purpose of this study is to explore the large amount of text data regarding comprehensive nursing care service extracted from online news and social media by applying a semantic network analysis. METHODS: The web pages of the Korean Nurses Association (KNA) News, major daily newspapers, and Twitter were crawled by searching the keyword ‘comprehensive nursing care service’ using Python. A morphological analysis was performed using KoNLPy. Nodes on a ‘comprehensive nursing care service’ cluster were selected, and frequency, edge weight, and degree centrality were calculated and visualized with Gephi for the semantic network. RESULTS: A total of 536 news pages and 464 tweets were analyzed. In the KNA News and major daily newspapers, ‘nursing workforce’ and ‘nursing service’ were highly rated in frequency, edge weight, and degree centrality. On Twitter, the most frequent nodes were ‘National Health Insurance Service’ and ‘comprehensive nursing care service hospital.’ The nodes with the highest edge weight were ‘national health insurance,’‘wards without caregiver presence,’ and ‘caregiving costs.’‘National Health Insurance Service’ was highest in degree centrality. CONCLUSION: This study provides an example of how to use atypical big data for a nursing issue through semantic network analysis to explore diverse perspectives surrounding the nursing community through various media sources. Applying semantic network analysis to online big data to gather information regarding various nursing issues would help to explore opinions for formulating and implementing nursing policies.
Boidae ; Caregivers ; Communications Media ; Humans ; Insurance, Health ; Nursing Care* ; Nursing Services ; Nursing* ; Periodicals ; Semantics* ; Social Media*

PURPOSE: The purpose of this study was to develop and evaluate the effect of a cultural competency promotion program for nurses in obstetrics-gynecology and pediatrics. METHODS: The cultural competency promotion program was developed through the Analysis, Design, Development, Implementation, and Evaluation (ADDIE) steps. In this quasi-experimental study, 30 nurses in obstetrics-gynecology and pediatrics were assigned to the experimental group and 34 nurses were assigned to the control group. The experimental group received this program once a week for four weeks and each class lasted one hour. Data were analyzed using descriptive statistics, t-test, chi2-test and Fisher's exact test with the IBM SPSS Statistics version 21.0 program. RESULTS: After attending the program, cultural competency (t=8.30, p<.001) increased significantly in the experimental group compared to the control group. There were also significant differences between two groups in cultural awareness (t=7.53, p<.001), cultural attitude (t=6.41, p<.001), and cultural knowledge & skills (t=7.79, p<.001) as components of cultural competency. CONCLUSION: The results of this study indicate that this cultural competency program is effective and efficient for nurses in obstetrics-gynecology and pediatrics and can help nurses provide appropriate multicultural nursing care in multicultural society.
Cultural Competency* ; Nursing Care ; Pediatrics* ; Program Development

Migration of cells along the right direction is of paramount importance in a number of in vivo circumstances such as immune response, embryonic developments, morphogenesis, and healing of wounds and scars. While it has been known for a while that spatial gradients in chemical cues guide the direction of cell migration, the significance of the gradient in mechanical cues, such as stiffness of extracellular matrices (ECMs), in directed migration of cells has only recently emerged. With advances in synthetic chemistry, micro-fabrication techniques, and methods to characterize mechanical properties at a length scale even smaller than a single cell, synthetic ECMs with spatially controlled stiffness have been created with variations in design parameters. Since then, the synthetic ECMs have served as platforms to study the migratory behaviors of cells in the presence of the stiffness gradient of ECM and also as scaffolds for the regeneration of tissues. In this review, we highlight recent studies in cell migration directed by the stiffness gradient, called durotaxis, and discuss the mechanisms of durotaxis. We also summarize general methods and design principles to create synthetic ECMs with the stiffness gradients and, finally, conclude by discussing current limitations and future directions of synthetic ECMs for the study of durotaxis and the scaffold for tissue engineering.
Artificial Cells ; Cell Movement ; Chemistry ; Cicatrix ; Cues ; Embryonic Development ; Extracellular Matrix ; Female ; Hydrogel* ; Hydrogels* ; Morphogenesis ; Pregnancy ; Regeneration ; Tissue Engineering* ; Wounds and Injuries