Relation of Dietary n-3 and n-6 Fatty Acid Intakes to Metabolic Syndrome in Middle-Aged People Depending on the Level of HbA1c: A Review of National Health and Nutrition Survey Data from 2014 to 2016.

Background and Objectives: The relation of dietary n-6 fatty acid to metabolic syndrome has not been examined and clearly defined. To improve health in the general population, this study was to investigate the role of n-3 and n-6 fatty acids in the reduction in metabolic syndrome and to observe changes in the effects of these fatty acids depending on the level of insulin resistance. Materials and Methods: This cross-sectional study utilized national health and nutrition survey data from 2014 to 2016. From the data, a relation of n-3 and n-6 fatty acid intakes to metabolic syndrome and Hemoglobin A1c (HbA1c)'s role in the relation was evaluated and analyzed for 4852 patients between 40 and 64 years old. Intake frequency of 112 nutrition and daily consumption amounts were identified, and intakes of n-3 and n-4 fatty acids were calculated from this data. Metabolic syndrome was determined for each participant using diagnostic standards for the Asian population published by the National Cholesterol Education Program. Results: Among the total 4852 subjects, 1583 (32.6%) had metabolic syndrome; 736 of 1875 (39.3%) males and 847 of 2977 (28.5%) females had the syndrome. In males, when their HbA1c was low (<5.4%), intakes of both n-3 and n-6 fatty acids were related to a 43−63% decreased prevalence of metabolic syndrome with significance, and a similar negative tendency was also observed in females. On the contrary, for both males and females, no statistically significant correlation was present when HbA1c was high. Conclusion: It was considered that consistent and regular dietary intakes of n-3 and n-6 fatty acids may contribute greatly to prevent or treat metabolic syndrome in healthy males with normal insulin sensitivity, but the effect of their dietary intakes was found to be limited in a group with strong insulin resistance. The conclusion of this study presents a valuable reference and knowledge to provide nutritional education to the general population.

Regional Gray Matter Volume Related to High Occupational Stress in Firefighters.

BACKGROUND: Firefighters inevitably encounter emotionally and physically stressful situations at work. Even firefighters without diagnosed post-traumatic stress disorder receive clinical attention because the nature of the profession exposes them to repetitive trauma and high occupational stress. This study investigated gray matter abnormalities related to high occupational stress in firefighters using voxel-based morphometry (VBM) and surface-based morphometry (SBM). METHODS: We assessed 115 subjects (112 males and 3 females) using magnetic resonance imaging and evaluated occupational stress by the Korean Occupational Stress Scale-26 (KOSS-26). Subjects were classified into highly or lowly stressed groups based on the median value of the KOSS-26. RESULTS: In VBM analysis, we found that firefighters with high occupational stress had lower gray matter volume (GMV) in both sides of the insula, the left amygdala, the right medial prefrontal cortex (mPFC), and the anterior cingulate cortex than firefighters with low occupational stress. In SBM analysis based on regions of interest, the GMV of the bilateral insula and right mPFC were also lower in the highly stressed group. Within the highly stressed group, low GMV of the insula was significantly correlated with the length of service (left: r = -0.347, P = 0.009; right: r = -0.333, P = 0.012). CONCLUSION: Our findings suggest that regional GMV abnormalities are related to occupational stress. Regional gray matter abnormalities and related emotional dysregulation may contribute to firefighter susceptibility to burnout.

Trauma Exposure and Suicidal Ideation among Korean Male Firefighters: Examining the Moderating Roles of Organizational Climate.

Background: This study investigated the relationship between trauma exposure and suicidal ideation. Moreover, this study examines the moderating roles of organizational climate on the association between trauma exposure and suicidal ideation in Korean male firefighters. Methods: A total of 15,104 male firefighters who completed a questionnaire were analyzed. The data were obtained using an online self-administered questionnaire from the Firefighter Research on Enhancement of Safety and Health Study. Poisson regression analysis was performed to determine the effects of trauma exposure on suicidal ideation and the moderating effect of organizational climate. Results: The results showed that 389 firefighters (2.6%) responded that they had experienced suicidal ideation. In the final model, trauma exposure was positively related to suicidal ideation (adjusted risk ratio [aRR], 1.076; 95% confidence interval [CI]: 1.051-1.103), and organizational climate was negatively associated with suicidal ideation (aRR, 0.772; 95% CI: 0.739-0.806). Additionally, the interaction term (trauma exposure × organizational climate) was related to suicidal ideation (aRR, 1.016; 95% CI: 1.009-1.023). Conclusions: This study suggests that trauma exposure might play a significant role in developing suicidal ideation and that positive organizational climate moderates the negative effects of trauma exposure on suicidal ideation among firefighters. It is necessary to perform a follow-up study of various intervention strategies to maintain a healthy organizational climate or work environment. Such interventions should promote lasting trust within teams, provide social support and belonging, and nurture job value.

Effects of Emergency Duties on Cardiovascular Diseases in Firefighters: A 13-Year Retrospective Cohort Study.

OBJECTIVES: This study aimed to examine the effects of firefighters' emergency duties on the incidence of cardiovascular disease (CVD). METHODS: We used a 13-year follow-up in a nationwide retrospective cohort study. A total of 363,137 employees were recruited. The sex-and age-specific incidence of CVD (hypertension, angina pectoris, and acutemyocardial infarction [AMI]) in firefighters and public officials was estimated. RESULTS: The overall age-specific sex-based incidence of CVD, except for hypertension, was higher in firefighters than in public officials. The age-stratified hazard ratios for the three types of CVD in male firefighters were also higher. AMI was more common in younger firefighters, whereas angina pectoris and hypertension were common in older firefighters. CONCLUSIONS: Firefighters' duties are more likely to increase the risk of CVD, and preventive strategies with proven benefits are required.

Anti-fibrotic effect of thalidomide through inhibiting TGF-beta-induced ERK1/2 pathways in bleomycin-induced lung fibrosis in mice.

OBJECTIVES: This study is designed to confirm the anti-fibrotic effect of thalidomide on bleomycin-induced lung fibrosis in a mouse model and to identify whether this anti-fibrotic effect is associated with inhibition of the transforming growth factor-beta (TGF-beta)-induced extracellular signal-regulated kinase1/2 (ERK1/2). METHODS AND MATERIALS: C57BL/6 female mice were administered blomycin sulfate. In cultured human lung fibroblasts, expressions of type I collagen, fibronectin, and either TGF-beta or IL-6 were measured after thalidomide treatment by reverse transcription-polymerase chain reaction (RT-PCR). Expressions of ERK1/2, type I collagen, fibronectin, and TGF-beta1 from lung tissues of blomycin-induced mice and from mouse lung fibroblasts were evaluated using RT-PCR and western blotting. RESULTS: Thalidomide administration significantly inhibits TGF-beta1 mRNA expression in a dose-dependant manner following administration of IL-6 and IL-6R. In the analysis of BAL fluids, total BAL inflammatory cell counts, TGF-beta1, and IL-6 levels in thalidomide-treated mice were significantly reduced when compared with bleomycin-treated mice (p < 0.01, p < 0.01, and p < 0.001, respectively). Thalidomide inhibited total ERK1/2 and phospho-ERK1/2 expression after TGF-beta1 stimulation in the RT-PCR and western blotting. CONCLUSION: The results of our study suggest that the anti-fibrotic effect of thalidomide on lung fibrosis may be related to suppression of the TGF-beta1-induced ERK1/2 signaling pathway.

Mediating Effects of Burnout in the Association Between Emotional Labor and Turnover Intention in Korean Clinical Nurses.

BACKGROUND: The current lack of the number of nurses and high nurse turnover rate leads to major problems for the health-care system in terms of cost, patient care ability, and quality of care. Theoretically, burnout may help link emotional labor with turnover intention. The purpose of this study was to investigate the mediating effect of burnout in the association between emotional labor and turnover intention in Korean clinical nurses. METHODS: Using data collected from a sample of 606 nurses from six Korean hospitals, we conducted a multiple regression analysis to determine the relationships among clinical nurses' emotional labor, burnout, and turnover intention, looking at burnout as a mediator. RESULTS: The results fully and partially support the mediating role of burnout in the relationship between the subfactors of emotional labor and turnover intention. In particular, burnout partially mediated the relationship between emotional disharmony and hurt, organizational surveillance and monitoring, and lack of a supportive and protective system in the organization. In addition, we found that burnout has a significant full mediation effect on the relationship between overload and conflicts in customer service and turnover intention. Although the mediating effect of burnout was significantly associated with the demands and regulation of emotions, no significant effects on turnover intention were found. CONCLUSION: To reduce nurses' turnover, we recommend developing strategies that target both burnout and emotional labor, given that burnout fully and partially mediated the effects of emotional labor on turnover intention, and emotional labor was directly associated with turnover intention.

Hypertension Is Associated with Increased Risk of Diabetic Lung.

Lung function is often impaired in diabetic patients, especially in a restrictive pattern, which has recently been described as the diabetic lung. Since hypertension (HTN) is common in diabetic patients, our study investigated whether HTN acts as an aggravating factor in diabetic lung. Within the cross-sectional study from the 6th Korean National Health and Nutrition Examination Survey (KNHANES), fasting plasma glucose (FPG), blood pressure (BP), pulmonary function, and laboratory data were examined in 4644 subjects aged between 40 and 79 years. A multivariate regression model was used to investigate the relationship between BP, FPG, and pulmonary function. Lung function was significantly reduced in the HTN (p = 0.001), impaired fasting glucose (IFG) (p < 0.001), and diabetes mellitus (DM) (p < 0.001) groups. Next, a multivariate logistic regression model was used to derive the odds ratio (OR) of reduced lung function based on the presence of IFG, DM, and HTN. The OR of reduced forced vital capacity (FVCp < 80%) was 3.30 (p < 0.001) in the HTN-DM group and 2.30 (p < 0.001) in the normal BP-DM group, when compared with the normal BP-normal FPG group. The combination of HTN and DM had the strongest negative effect on FVC. The results presented in this study indicate that diabetes and hypertension have a synergistic association with impaired lung function.

Organizational Climate Effects on the Relationship Between Emotional Labor and Turnover Intention in Korean Firefighters.

BACKGROUND: The purpose of this study is to examine the combined effects of organizational climate (OC) with emotional labor (EL) on turnover intention in Korean firefighters. METHODS: The data were obtained from the study Firefighters Research: Enhancement of Safety and Health. A total of 4,860 firefighters whose main duty was providing "emergency medical aid" were included. To examine the effects of OC on the relationships between five subscales of EL and turnover intention, four groups were created using various combinations of OC ("good" vs. "bad") and EL ("normal" vs. "risk"): (1) "good" and "normal" (Group I), (2) "bad" and "normal" (Group II), (3) "good" and "risk" (Group III), and (4) "bad" and "risk" (Group IV). Multivariate logistic regression analyses were performed to estimate the risk of turnover intention for the combinations of OC and EL. RESULTS: The results showed turnover intention was significantly higher in the group with "bad" OC (17.7%) than in that with "good" OC (7.6%). Combined effects of OC and EL on turnover intention were found in all five subscales with the exception of Group I for emotional demands and regulation. Groups II, III, and IV were more likely to experience risks of turnover intention than Group I (p for trend <0.001). CONCLUSIONS: A positive and cooperative OC plays a role in decreasing the risk of turnover intention and in attenuating the negative effects of EL on turnover intention in firefighters.

Blood pressure and the risk of major adverse cardiovascular events among firefighters.

OBJECTIVE: No long-term follow-up study has investigated the effect of blood pressure (BP) on cardiovascular disease mortality and morbidity in firefighters. To investigate the effects of BP on the risk of major adverse cardiovascular events (MACEs) using a national representative population-matched cohort. METHODS: We enrolled all firefighters (N = 8242) and 28 678 referent controls aged more than 40 years who underwent baseline health examinations in 2002 and 2003. Records of hospitalization and mortality until 2015 were checked. To evaluate the causal effect of BP on MACE, subcohort analysis using a propensity score-matched (PSM) cohort with respect to job classification (firefighter vs. control) was performed. RESULTS: Hypertension significantly increased the risk of MACEs compared with normal BP in both firefighters and the age--sex matched cohort, but in participants with elevated BP, significantly increased risk of MACEs [hazards ratio 1.41, 95% confidence interval (CI) 1.06-1.88] was observed only among firefighters. In the PSM cohort, firefighters had a significantly higher risk of death or hospitalization from MACEs (hazard ratio 1.29, 95% CI 1.14-1.47), myocardial infarction (hazard ratio 1.24, 95% CI 1.07-1.43), and ischemic stroke (hazard ratio 1.43, 95% CI 1.12-1.82) than controls. Firefighters with elevated BP (hazard ratio 1.58, 95% CI 1.04-2.40), stage 1 (hazard ratio 1.24, 95% CI 1.00-1.52), and stage 2 (hazard ratio 1.39, 95% CI 1.13-1.71) hypertension had higher risk of MACEs than PSM controls. CONCLUSION: Firefighters showed significantly higher cardiovascular risk than referent controls when comparing those within the same BP category, suggesting that firefighters with elevated BP and hypertension may be at high risk of adverse prognosis.

Effect of Burnout on Post-traumatic Stress Disorder Symptoms Among Firefighters in Korea: Data From the Firefighter Research on Enhancement of Safety & Health (FRESH).

OBJECTIVES: It is well-known that post-traumatic stress disorder (PTSD) among firefighters contributes to their job-related stress. However, the relationship between burnout and PTSD in firefighters has rarely been studied. This study therefore explored the association between burnout and its related factors, such as trauma and violence, and PTSD symptoms among firefighters in Korea. METHODS: A total of 535 firefighters participated in the Firefighter Research on Enhancement of Safety & Health study at 3 university hospitals from 2016 to 2017. The 535 participants received a baseline health examination, including questionnaires assessing their mental health. A Web-based survey was also conducted to collect data on job-related stress, history of exposure to violence, burnout, and trauma experience. The associations among burnout, its related factors, and PTSD symptoms were investigated using structural equation modeling. RESULTS: Job demands (ß=0.411, p<0.001) and effort-reward balance (ß=-0.290, p<0.001) were significantly related to burnout. Burnout (ß=0.237, p<0.001) and violence (ß=0.123, p=0.014) were significantly related to PTSD risk. Trauma (ß=0.131, p=0.001) was significantly related to burnout; however, trauma was not directly associated with PTSD scores (ß=0.085, p=0.081). CONCLUSIONS: Our results show that burnout and psychological, sexual, and physical violence at the hands of clients directly affected participants' PTSD symptoms. Burnout mediated the relationship between trauma experience and PTSD.

Herbal Medicines for Cold Hypersensitivity in the Hands and Feet: A Systematic Review and Meta-Analysis.

Objectives: Cold hypersensitivity in the hands and feet (CHHF) and Raynaud's phenomenon (RP) are prevalent among Asian populations, especially among women, who exhibit a higher rate of cold hypersensitivity that may be associated with gynecological problems. In several countries, herbal medicine has effectively treated cold hypersensitivity symptoms. This systematic review and meta-analysis of the literature was undertaken to evaluate the efficacy of herbal medicine for the treatment of CHHF in adults. Design: Through March 31, 2018, comprehensive databases were searched, including MEDLINE, EMBASE, Cochrane Library, Chinese Academic Journal, and Japanese National Institute of Informatics, to identify relevant studies and extract data. Outcome measures: Primary: total effective rate (TER); secondary: skin temperature, peripheral blood flow, adverse events. Results: Fourteen randomized controlled trials (n = 974) were included. Thirteen studies with dichotomous values showed a significant reduction in CHHF and RP (risk ratio 0.31, 0.24-0.40) when comparing herbal medicine with/without Western medicine, and no treatment or Western medicine alone. Reductions in CHHF and RP were also observed between herbal medicine plus Western medicine and Western medicine alone (risk ratio 0.45, 0.24-0.86), as well as between herbal medicine and Western medicine alone (risk ratio 0.30, 0.21-0.41). In the only study using a placebo arm, herbal medicine was found to be superior to placebo in increasing skin temperature and peripheral blood flow. Six participants exhibited minor adverse drug reactions. Herbal medicine showed a superior TER, especially when combined with Western medicine, to Western medicine alone or placebo. However, there was a high risk of bias within all studies. Conclusion: Although herbal medicine shows potential to be a safe and effective treatment for CHHF and RP, the high risk of bias in all studies prevents definitive conclusions; thus, higher quality studies must be performed.

Epithelial-mesenchymal transition in patients of pulmonary adenocarcinoma: correlation with cancer stem cell markers and prognosis.

Adenocarcinoma is the most common histologic type of non-small cell lung carcinomas. The existence of lung cancer stem cells (CSCs) and epithelial-mesenchymal transition (EMT) in human tissue is controversy. The aim of this study is to investigate the expression and clinical significance of CSCs and EMT markers and evaluate the correlation between the two in lung adenocarcinoma. A total of 97 cases comprise the tissue microarray from surgical resection for primary lung adenocarcinoma. Immunohistochemistry for ALDH1 and CD44 as CSC markers and E-cadherin, vimentin, fibronectin, SMA as EMT markers was performed. High ALDH1A1 expression was statistically associated with female gender (P=0.001), smoker (P=0.012), and high pT stages (P=0.046). High CD44 expression was statistically associated with female gender (P=0.008), non-smoker (P=0.000), and no pleural invasion (P=0.039). High expression of ALDH1 was associated with good overall survival (P=0.021). High expression of CD44 was correlated with both good overall survival (P=0.024) and disease-free survival (P=0.000). Vimentin expression was associated with pT stage (P=0.001) and pleural invasion (P=0.028). E-cadherin, fibronectin and SMA were not associated with clinicopathologic correlation and all EMT markers were not correlated with survival of lung adenocarcinoma. CSC markers expression was not related to EMT. Our results showed that the expression of CSCs was associated with a good prognosis in lung adenocarcinoma. The prognostic significance of EMT markers was skeptical in this study. There is a need for more research about CSC, EMT, and the relation between these two in human lung adenocarcinoma.

Lung cancer detection by a RT-nested PCR using MAGE A1--6 common primers.

BACKGROUND: Since the mortality of lung cancer patients remains very high, the development of a sensitive detection method remains an urgent task. The authors have designed common melanoma antigen gene (MAGE) primers that enable the detection of MAGE A1 to A6 subtypes simultaneously. These primers were applied to the detection of lung cancer using sputum specimens. METHODS: The study involved, 53 cancer patients and three non-cancer groups (193 healthy people, 235 lung cancer screening group and 140 patients with benign lung diseases) were investigated. One hundred and thirty-six respiratory specimens (55 random sputa, 33 induced sputa, 40 broncho-alveolar lavage (BAL) fluids, and 8 pleural fluids) from different lung cancer patients were blindly tested. The MAGE assay was performed by RT-nested PCR, and the results obtained from sputum were compared with those obtained by telomerase assay and conventional cytology. RESULTS: In the sputum of the non-cancer groups, the positive rates were less than 2.1%, while the detection rates were 83.3% in the cancer tissues and 54.3% in the sputa of lung cancer patients. For the random sputum samples of lung cancer patients, the detection rate was 47.5%, but in the induced sputum, BAL and pleural fluids, the detection rate was up to over 70.0%. The MAGE assay produced a higher detection rate than the telomerase assay and conventional cytology. CONCLUSIONS: MAGE A1-6 RT-PCR, which showed high sensitivity and specificity, provides an effective means for the lung cancer detection in sputum.

Possible association between serotonin transporter promoter region polymorphism and impulsivity in Koreans.

Serotonin has become the major focus of biological studies of suicidal behavior and impulsive-aggressive behavior in humans. The serotonin transporter (5-HTT) gene is one of the important genes involved in the regulation of serotonin transmission. We examined the association of impulsivity in Korean populations with a functional polymorphism of the promoter region of the 5-HTT gene (5-HTTLPR). We recruited 186 adolescent prisoners and 64 medical students. Impulsivity was measured using the Barratt Impulsiveness Scale and we divided all subjects into three groups: impulsive subjects (IS, N=121), non-impulsive subjects (NIS, N=115) and an intermediate group (excluded, N=14). The 5-HTTLPR genotype was determined by polymerase chain reaction. All subjects were Korean men unrelated to each other. There were no significant differences in the genotype frequency of 5-HTTLPR-S/S, S/L and -L/L between the two groups in the Korean population (IS vs. NIS: 47.9 vs. 61.7%; 43.0 vs. 32.2%; and 9.1 vs. 6.1%, respectively). However, there was a statistically significant difference in allelic frequency of 5-HTTLPR-S and 5-HTTLPR-L between the two groups in the Korean population (IS vs. NIS: 69.4 vs. 77.8%; and 30.6 vs. 22.2%, respectively. From our results, this 5-HTTLPR polymorphism appears to be a possible candidate gene for impulsivity in the Korean population.

Detection of EGFR mutations in circulating free DNA by PNA-mediated PCR clamping.

BACKGROUND: Epidermal growth factor receptor (EGFR)-activating mutations are major determinants in predicting the tumor response to EGFR tyrosine kinase inhibitors in non-small cell lung cancer (NSCLC). Noninvasive test for the detection of EGFR mutations is required, especially in NSCLC patients from whom tissue is not available. In this study, we assessed the feasibility of detection of EGFR mutations in free DNA circulating in plasma. METHODS: Plasma samples of 60 patients with partial response to gefitinib were analyzed to detect EGFR-activating mutations in exons 19 and 21. Forty (66.7%) of patients had tumor EGFR mutation results. EGFR mutations in plasma were detected using the peptide nucleic acid (PNA)-mediated polymerase chain reaction (PCR) clamping method. All clinical data and plasma samples were obtained from 11 centers of the Korean Molecular Lung Cancer Group (KMLCG). RESULTS: Of the 60 patients, 39 were female and the median age was 62.5 years. Forty-three patients never smoked, 53 had adenocarcinomas, and seven had other histologic types. EGFR-activating mutation was detected in plasma of 10 cases (exon 19 deletion in seven and exon 21 L858R point mutation in three). It could not be found in plasma after treatment for 2 months. When only patients with confirmed EGFR mutation in tumor were analyzed, 17% (6 of 35) of them showed positive plasma EGFR mutation and the mutation type was completely matched with that in tumor. There was no statistically significant difference in clinical parameters between patients with EGFR mutations in plasma and those without EGFR mutations. CONCLUSIONS: The detection rate of EGFR mutations from plasma was not so high despite highly sensitive EGFR mutation test suggesting that more advances in detection methods and further exploration of characteristics of circulating free DNA are required.

Lymphocytic interstitial pneumonia in primary Sjögren's syndrome: a case report.

Sjögren's syndrome (SS) is an autoimmune disorder in which lymphocytes infiltrate the exocrine glands, resulting in the development of sicca symptoms. Lymphocytes may also invade various other organs and cause diverse symptoms. Interstitial pneumonia has been observed frequently in SS patients. Typically, the pneumonia responds well to systemic steroids, and fatal cases are rare. We experienced a case of lymphocytic pneumonia accompanied by SS and treated with cyclophosphamide pulse therapy, and we present details of the case herein.

A preliminary study of protoporphyrin-IX as a potential candidate for identification of lung cancer cells using fluorescence microscopy.

OBJECTIVES: There is need for a cheap, sensitive, and specific method to identify and localize early stage lung cancer. In order to improve the sensitivity of fluorescent agents that exhibit selective tumor uptake that are used as population screening tools for the detection of early lung cancer, a number of porphyrins including protoporphyrin-IX (PpIX) were tested. We stained lung cancer cells using three different sample preparation schemes for fluorescence microscopy. METHODS: Lung tissues and sputum samples of nineteen patients were studied. Cells were collected on glass slides by touching tumor surfaces of surgically sectioned lung cancer tissue and normal regions of the lung during surgery. Filtered sputum cells were also collected. Cell-attached slides were stained with porphyrin using three different methods, including fixing (SM-1) prior to staining, and diluting porphyrin stock solutions in either RPMI-1640 medium (SM-2) or 100mM MES buffer (SM-3). RESULTS: Slides from normal lung tissue lacked fluorescent epithelial cells. Tumor slides containing typical lung cancer cells exhibited red fluorescence upon excitation through the soret band (400-450 nm) of porphyrin compounds. Tumor-selective staining was only observed on unfixed tumor slides that were incubated with PpIX in a RPMI-1640 culture medium (SM-3) used as a working solution for staining and washing. CONCLUSIONS: Protoporphyrin-IX is a potentially useful tumor-staining molecular agent for fluorescent location of cancer cell in sputum samples from lung cancer patients.