Purpose: This study aimed to examine effect sizes of leadership styles of nursing managers on turnover intention of hospital nurses. Methods: A systematic review and meta-analysis were conducted in accordance with the PRISMA and MOOSE guidelines. Participants were nurses working in hospitals. The intervention involved nursing managers’ leadership styles; the outcome assessed was nurses’ turnover intention. This was an observational study design. Eleven databases were searched to obtain articles published in Korean or English. Of the 14,428 articles reviewed, 21 were included in systematic review and meta-analysis. Comprehensive Meta-Analysis and R software programs were used. Results: The total effect size r (ESr) was - 0.25 (95% confidence interval: - 0.29 to - 0.20). Effect sizes of each leadership style on turnover intention were as follows: ethical leadership (ESr = - 0.34), transformational leadership (ESr = - 0.28), authentic leadership (ESr = - 0.23), transactional leadership (ESr = - 0.21), and passive avoidant leadership (ESr = 0.13). Ethical leadership was the most effective style in decreasing turnover intention of hospital nurses. Conclusion Positive leadership styles of nurse managers effectively decrease turnover intention of hospital nurses, and negative leadership styles of nurse managers effectively increase turnover intention of hospital nurses. The ethical leadership style is the most effective in decreasing turnover intention of hospital nurses; however, it requires careful interpretation as its effects are reported by only two studies. This study contributes to addressing the high turnover rate of hospital nurses and developing positive leadership styles of nurse managers in hospital settings.

Gefitinib is an anti-cancer drug used to treat non-small cell lung cancer. The objective of this study was to compare the pharmacokinetics and evaluate the bioequivalence of 2 orally administered gefitinib 250 mg tablets in healthy Korean subjects. A randomized, openlabel, single-dose, crossover bioequivalence study was conducted. A total of 50 healthy male volunteers were randomized into 2 sequence groups. During each treatment, the subjects received the test or reference formulation of 250 mg gefitinib with a washout period of 21 days. The plasma samples were collected at pre-dose and up to 144 hours post-dose, and plasma drug concentrations were measured using validated liquid chromatography-tandem mass spectrometry. Pharmacokinetic parameters were calculated, and the formulations were considered as bioequivalent if the 90% confidence intervals (CIs) of the geometric mean ratios were within the bioequivalence limits of 0.8 to 1.25. Forty-one subjects completed the study and were included in the pharmacokinetic analysis. The 90% CIs of the geometric mean ratios of the test formulation to the reference formulation were 0.8115 to 0.9993 for maximum plasma concentration and 0.9119 to 1.0411 for area under the plasma concentration versus time curve from dosing to the last measurable concentration. There were no serious or unexpected adverse events during the study. In healthy Korean adult subjects, the test and reference formulations of gefitinib 250 mg had similar pharmacokinetic parameters and similar plasma concentration-time profiles. The test formulation of gefitinib met the regulatory criteria for assuming bioequivalence. Both formulations were safe and well-tolerated.

Background: Pure mucinous carcinoma (PMC) is a rare type of breast cancer, estimated to represent 2% of invasive breast cancer. PMC is typically positive for estrogen receptors (ER) and progesterone receptors (PR) and negative for human epidermal growth factor receptor 2 (HER2). The clinicopathologic characteristics of HER2-positive PMC have not been investigated. Methods: Pathology archives were searched for PMC diagnosed from January 1999 to April 2018. Clinicopathologic data and microscopic findings were reviewed and compared between HER2-positive PMC and HER2-negative PMC. We also analyzed the differences in disease-free survival (DFS) and overall survival according to clinicopathologic parameters including HER2 status in overall PMC cases. Results: There were 21 HER2-positive cases (4.8%) in 438 PMCs. The average tumor size of HER2-positive PMC was 32.21 mm (± 26.55). Lymph node metastasis was present in seven cases. Compared to HER2-negative PMC, HER2-positive PMC presented with a more advanced T category (p < .001), more frequent lymph node metastasis (p = .009), and a higher nuclear and histologic grade (p < .001). Microscopically, signet ring cells were frequently observed in HER2-positive PMC (p < .001), whereas a micropapillary pattern was more frequent in HER2-negative PMC (p = .012). HER2-positive PMC was more frequently negative for ER (33.3% vs. 1.2%) and PR (28.6% vs. 7.2%) than HER2-negative PMC and showed a high Ki-67 labeling index. During follow-up, distant metastasis and recurrence developed in three HER2-positive PMC patients. Multivariate analysis revealed that only HER2-positivity and lymph node status were significantly associated with DFS. Conclusions Our results suggest that HER2-positive PMC is a more aggressive subgroup of PMC. HER2 positivity should be considered for adequate management of PMC.

BACKGROUND/AIMS: Tens of trillions of microorganisms constitute the gut microbiota of the human body. The microbiota plays a critical role in maintaining host immunity and metabolism. Analyses of the gut microbial composition in Korea are limited to a few studies consisting of small sample sizes. To investigate the gut microbial community in a large sample of healthy Koreans, we analyzed the 16S ribosomal RNA of 4 representative bacterial genera Lactobacillus, Bifidobacterium, Bacteroides, and Clostridium. METHODS: A total of 378 DNA samples extracted from 164 infants and 214 adults were analyzed using quantitative real-time polymerase chain reaction. RESULTS: Analysis of 16S ribosomal RNA of 4 representative bacterial genera Lactobacillus, Bifidobacterium, Bacteroides, and Clostridium showed that the gut microbiota in infants had higher relative abundances of Bifidobacterium and Lactobacillus than that in adults, which was dominated by Bacteroides and Clostridium. CONCLUSIONS: To the best of our knowledge, this was the first study evaluating the distinct characteristics of the microbial community of Korean infants and adults. The differences between the 2 populations suggest that external factors such as age, diet, and the environment are important contributing factors to the change in gut microbial composition during development.
Adult ; Bacteroides ; Bifidobacterium ; Clostridium ; Diet ; DNA ; Gastrointestinal Microbiome ; Human Body ; Humans ; Infant ; Korea ; Lactobacillus ; Metabolism ; Microbiota* ; Real-Time Polymerase Chain Reaction ; RNA, Ribosomal, 16S ; Sample Size ; Transcutaneous Electric Nerve Stimulation

Volumetric absorptive microsampling (VAMS) is a novel sampling technique that allows for the collection of an accurate volume of blood by dipping a microsampler tip. The purpose of this study is to compare the requirement of a stabilizing reagent for the conventional venous blood sampling method versus VAMS in the analytical measurement of the concentration of acetylsalicylic acid. A high-performance liquid chromatography with mass spectrometry (LC-MS/MS) method was developed and validated for the accurate determination of acetylsalicylic acid in human blood. The blood samples spiked with acetylsalicylic acid with and without stabilizing reagent were absorbed into VAMS tips. In the whole blood sample, the same concentration was shown regardless of the addition of the stabilizing reagent, but the concentration decreased when the stabilizing reagent was not added to the VAMS sample. To apply the VAMS technology as a new blood sampling method, stabilizing reagents should be added before the analysis of acetylsalicylic acid concentration.
Aspirin ; Chromatography, Liquid ; Humans ; Indicators and Reagents ; Mass Spectrometry ; Methods

OBJECTIVE: Dyslipidemia is recognized as a prominent risk factor for cardiovascular and cerebrovascular diseases but it is manageable through therapeutic and lifestyle intervention. Interpreting the latest guidelines is essential for an application of recommendation from guidelines into clinical practice. Therefore, this study aimed to compare the most recent guidelines on dyslipidemia treatment recommendations in Korea and USA. METHODS: This study analyzed and compared 2015 Korean guidelines for the management of dyslipidemia, 2013 American College of Cardiology/American Heart Association (ACC/AHA) guideline and 2016 supportive guidelines from ACC. RESULTS: A comparison was made focused on the following: target patients based on cardiovascular risk assessment, target goal, and treatment strategies including statin and non-statin therapies. Four target patient groups by risk were suggested in 2015 Korean guideline and cardiovascular risk factors were also considered for initiation of lipid lowering therapy. Titrated statin regimen was recommended by Korean guideline to reach LDL cholesterol and non-HDL cholesterol target level. In 2013 ACC/AHA guideline, four statin benefit group was introduced considering ASCVD risk and high intensity statin or intermediate intensity statin use were recommended without dose titration. 2016 update was to support non-statin therapy based on updated evidence and new consideration of ezetimibe, PCSK9-inhibitor and bile acid sequestrant was brought up. CONCLUSION: Guidelines are continuously updating as new and important clinical data are constantly released along with the advent of newly approved drugs for lipid disorder. This article provides resources that facilitates uptake of these recommendations into clinical practice.

OBJECTIVES: This study was conducted to compare adolescents’ health behaviors and psychological status according to whether or not their mother was born in Korea. METHODS: This secondary analysis used nationally representative data from the 2015 Korean Youth Risk Behavior Web-based Survey. The self-administered questionnaire included computer measured socio-demographic variables, 15 health behaviors, and psychological status. Data from 65,426 middle school and high school students were analyzed. Multiple logistic regression, adjusting for socio-demographic variables, was used to analyze differences in health behaviors and psychological status between adolescents with a foreign-born mother and those with a Korean mother. RESULTS: Adolescents who have foreign-born mothers had a lower level of current drinking and subjective happiness, but a higher stress level. CONCLUSION: The stress levels of the adolescents with foreign-born mothers could be affected by their multicultural background. It is necessary to analyze stress-influencing factors of multicultural adolescents by comparing them to adolescents from Korean parents. Additionally, our society should pay more attention to the mental health of multicultural adolescents. Schools should also make various efforts to protect multicultural adolescents by adopting mental health management programs led by school nurses and counselors.
Adolescent ; Counseling ; Drinking ; Ethnic Groups* ; Happiness ; Health Behavior* ; Humans ; Korea ; Logistic Models ; Mental Health ; Mothers ; Parents ; Risk-Taking

A high performance liquid chromatography (HPLC) paired with UV-vis detection method to determine ascorbic acid and its oxidation product, dehydroascorbic acid, in human plasma was developed. Ascorbic acid in human plasma was extracted and stabilized using 10% metaphosphoric acid, and was analyzed by a Symmetry C18 column with 5 mM Hexadecyltrimethylammonium bromide and 50 mM KH2PO4 solution as the mobile phase (1.0 mL/min flow rate). Isoascorbic acid served as the internal standard and ultraviolet detector wavelength was 254 nm and 265 nm. Dehydroascorbic acid concentration was calculated from the differences in ascorbic acid concentration before and after reduction by dithiothreitol reagent. Quantification for ascorbic acid in human plasma was linear from 1–100 µg/mL. The inter- and intra-day precisions and accuracy were determined and the results were found to be within ±15%. This method was successfully applied to a human pharmacokinetic study of ascorbic acid as well as dehydroascorbic acid after oral administration of 4,000 mg vitamin C tablets to healthy Korean volunteers.
Administration, Oral ; Ascorbic Acid* ; Chromatography, High Pressure Liquid ; Chromatography, Liquid ; Dehydroascorbic Acid* ; Dithiothreitol ; Humans* ; Plasma* ; Tablets ; Volunteers

PURPOSE: The purpose of this study was to investigate factors affecting childhood asthma and atopic dermatitis. METHODS: For this study, data for 1,170 children (1-11 years) from the Fifth Korean National Health and Nutrition Examination Survey (KNHANES V-2, 2011) were analyzed. First correlation matrices were computed to test the normality of every data set and then to be in accordance with the real demographic composition, data were added weight before being analyzed. RESULTS: The child with asthma of a three generation family (OR=3.91, 95% CI [1.33, 11.45], p=.013) compared with a two generation family showed higher asthma development, and maternal asthma (OR=9.71, 95% CI [2.66, 35.40], p=.001) showed higher asthma development in child. The only factor affecting atopic dermatitis was parental perceptions of child health: poor (OR=3.40, 95% CI [1.29, 8.98], p=.014). CONCLUSION: These results suggest that childhood asthma and atopic dermatitis are both affected by parental perceptions of child health. Accordingly, management and support programs for children who have asthma and/or atopic dermatitis and their families should be comprehensive and also give attention to any other health problems because health perception represents quality of life.
Asthma* ; Child Health ; Child* ; Cross-Sectional Studies* ; Dataset ; Dermatitis, Atopic* ; Humans ; Nutrition Surveys ; Parents ; Quality of Life

OBJECTIVES: The prevalence of aged individuals in the Korean workforce continues to increase. This research determined the health and working conditions of Korean older wage workers and confirmed the effects of factors on the health-related quality of life of Korean older workers. METHODS: Of the 25,534 persons surveyed in the fifth Korea National Health and Nutrition Examination Survey, 1368 older (>55 years of age) wage workers without missing variables were selected. Their general characteristics, health status (cardiovascular disease, musculoskeletal disease, and mental health), working conditions (type of occupation, employment status, full- or part-time work, weekly average working hours, and shift work), and health-related quality of life assessed by the EQ-5D questionnaire were examined. RESULTS: The mean values of the EQ-5D index of the male and female older workers were 0.956 +/- 0.087 and 0.917 +/- 0.124, respectively (p < 0.001). The factors that caused statistically significant differences in the EQ-5D index for all subjects were age, education, household income, cerebro-cardiovascular event, osteoarthritis, musculoskeletal pain, stress, occupation type, employment status, and working hours. In logistic regression analysis, the factors that associated with perceived problems in each EQ-5D dimensions were age, musculoskeletal pain, stress, diabetes, smoking, occupation type, employment status, and working hours. CONCLUSIONS: To eventually raise the quality of life of older workers through health maintenance and management, it is necessary to manage related factors that include of musculoskeletal pain and diseases, stress, diabetes, smoking, occupation, employment status, and working hours.
Education ; Employment ; Family Characteristics ; Female ; Humans ; Korea ; Logistic Models ; Male ; Musculoskeletal Diseases ; Musculoskeletal Pain ; Nutrition Surveys ; Occupations ; Osteoarthritis ; Prevalence ; Quality of Life* ; Salaries and Fringe Benefits ; Smoke ; Smoking