Background: Previous studies have reported that oxidative stress contributes to obesity characterized by adipocyte hypertrophy. However, mechanism has not been studied extensively. In the current study, we evaluated role of extracellular vimentin secreted by oxidized low-density lipoprotein (oxLDL) in energy metabolism in adipocytes. Methods: We treated 3T3-L1-derived adipocytes with oxLDL and measured vimentin which was secreted in the media. We evaluated changes in uptake of glucose and free fatty acid, expression of molecules functioning in energy metabolism, synthesis of adenosine triphosphate (ATP) and lactate, markers for endoplasmic reticulum (ER) stress and autophagy in adipocytes treated with recombinant vimentin. Results: Adipocytes secreted vimentin in response to oxLDL. Microscopic evaluation revealed that vimentin treatment induced increase in adipocyte size and increase in sizes of intracellular lipid droplets with increased intracellular triglyceride. Adipocytes treated with vimentin showed increased uptake of glucose and free fatty acid with increased expression of plasma membrane glucose transporter type 1 (GLUT1), GLUT4, and CD36. Vimentin treatment increased transcription of GLUT1 and hypoxia-inducible factor 1α (Hif-1α) but decreased GLUT4 transcription. Adipose triglyceride lipase (ATGL), peroxisome proliferator-activated receptor γ (PPARγ), sterol regulatory element-binding protein 1 (SREBP1), diacylglycerol O-acyltransferase 1 (DGAT1) and 2 were decreased by vimentin treatment. Markers for ER stress were increased and autophagy was impaired in vimentin-treated adipocytes. No change was observed in synthesis of ATP and lactate in the adipocytes treated with vimentin. Conclusion We concluded that extracellular vimentin regulates expression of molecules in energy metabolism and promotes adipocyte hypertrophy. Our results show that vimentin functions in the interplay between oxidative stress and metabolism, suggesting a mechanism by which adipocyte hypertrophy is induced in oxidative stress.

OBJECTIVES: We estimated the population prevalence of antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including unreported infections, through a Korea Seroprevalence Study of Monitoring of SARS-CoV-2 Antibody Retention and Transmission (K-SEROSMART) in 258 communities throughout Korea. METHODS: In August 2022, a survey was conducted among 10,000 household members aged 5 years and older, in households selected through two stage probability random sampling. During face-to-face household interviews, participants self-reported their health status, COVID-19 diagnosis and vaccination history, and general characteristics. Subsequently, participants visited a community health center or medical clinic for blood sampling. Blood samples were analyzed for the presence of antibodies to spike proteins (anti-S) and antibodies to nucleocapsid proteins (anti-N) SARS-CoV-2 proteins using an electrochemiluminescence immunoassay. To estimate the population prevalence, the PROC SURVEYMEANS statistical procedure was employed, with weighting to reflect demographic data from July 2022. RESULTS: In total, 9,945 individuals from 5,041 households were surveyed across 258 communities, representing all basic local governments in Korea. The overall population-adjusted prevalence rates of anti-S and anti-N were 97.6% and 57.1%, respectively. Since the Korea Disease Control and Prevention Agency has reported a cumulative incidence of confirmed cases of 37.8% through July 31, 2022, the proportion of unreported infections among all COVID-19 infection was suggested to be 33.9%. CONCLUSIONS The K-SEROSMART represents the first nationwide, community-based seroepidemiologic survey of COVID-19, confirming that most individuals possess antibodies to SARS-CoV-2 and that a significant number of unreported cases existed. Furthermore, this study lays the foundation for a surveillance system to continuously monitor transmission at the community level and the response to COVID-19.

Purpose: This study aimed to identify the changes in dietary behavior of shift work nurses and its influencing factors over time. Methods: This was a secondary data analysis study based on the Shift Work Nurses’ Health and Turnover study. Data of 165 shift work nurses, who were followed for three-time points [before shift work (T0), after 6 months (T1), and after 18 months(T2) of shift work], were analyzed. Dietary behavior, level of stress, fatigue, depressive symptoms, and the amount of physical activity were measured. SPSS 28.0 was used to analyze the data to acquire descriptive statistics, repeated-measures ANOVA, and multiple linear regression with generalized estimating equations (GEE). Results: Dietary behavior of shift work nurses was poorer at T1 and T2 as compared to T0. As a result of GEE, shift work duration, level of stress, fatigue, and depressive symptoms were found to have negative impacts on dietary behavior. Conclusion Dietary behavior deteriorated and remained poor over time since shift work began. Shift work, along with stress, fatigue, and depressive symptoms, were the factors influencing their dietary behavior. Thus, to improve shift work nurses’ dietary behavior, efforts to decrease stress, and alleviate fatigue and depressive symptoms are urgently required.

Purpose: This study aimed to examine the changes in stress, occupational stress, and subjective health problems of novice female nurses within the first 18 months of work. Methods: This was a longitudinal study conducted with a secondary data analysis based on the Shift Work Nurse’s Health and Turnover (SWNHT) study. The participants were 178 female novice nurses who participated in all 3 data collection activities (on the first day of orientation before ward placement [T0], 6 months after work [T1], and 18 months after work [T2]). The stress, occupational stress, 8 subjective health problems (upper musculoskeletal pain, leg/foot discomfort, depression, anxiety or emotional disorder, sleep disturbance, headache, gastrointestinal disorder, menstrual disorder, and others), and the greatest health problem during the study period were measured, respectively. Data were analyzed using SPSS 26.0 to obtain descriptive statistics. Results: The subjective health of novice female nurses were found to be poor at T1 compared to T0 on both physical (upper musculoskeletal pain, leg/foot discomfort, and sleep disturbance) and psychological health problems (depression and stress). However, the psychological health problems of the participants were alleviated at T2 whereas; physical health problems persisted until T2. Conclusion Novice nurses had poor health problems 6 months after work. Sleep disturbance and musculoskeletal pain persisted although other health problems such as depression and stress were alleviated over the period. Strategies to prevent and manage different health problems of novice female nurses at different work duration are urgently needed.

Background: Estrogen promotes glucose homeostasis, enhances insulin sensitivity, and maintains counterregulatory responses in recurrent hypoglycemia in women of reproductive age. Postmenopausal women with type 2 diabetes mellitus (T2DM) might be more vulnerable to severe hypoglycemia (SH) events. However, the relationship between reproductive factors and SH occurrence in T2DM remains unelucidated. Methods: This study included data on 181,263 women with postmenopausal T2DM who participated in a national health screening program from January 1 to December 31, 2009, obtained using the Korean National Health Insurance System database. Outcome data were obtained until December 31, 2018. Associations between reproductive factors and SH incidence were assessed using Cox proportional hazards models. Results: During the mean follow-up of 7.9 years, 11,279 (6.22%) postmenopausal women with T2DM experienced SH episodes. A longer reproductive life span (RLS) (≥40 years) was associated with a lower SH risk compared to a shorter RLS (<30 years) (adjusted hazard ratio [HR], 0.74; 95% confidence interval [CI], 0.69 to 0.80; P for trend <0.001) after multivariable adjustment. SH risk decreased with every 5-year increment of RLS (with <30 years as a reference [adjusted HR, 0.91; 95% CI, 0.86 to 0.95; P=0.0001 for 30−34 years], [adjusted HR, 0.80; 95% CI, 0.76 to 0.84; P<0.001 for 35−39 years], [adjusted HR, 0.74; 95% CI, 0.68 to 0.81; P<0.001 for ≥40 years]). The use of hormone replacement therapy (HRT) was associated with a lower SH risk than HRT nonuse. Conclusion Extended exposure to endogenous ovarian hormone during lifetime may decrease the number of SH events in women with T2DM after menopause.

Sjögren's syndrome (SS) is an autoimmune disease characterized by dryness of the mouth and eyes. The glandular dysfunction in SS involves not only T cell-mediated destruction of the glands but also autoantibodies against the type 3 muscarinic acetylcholine receptor or aquaporin 5 (AQP5) that interfere with the secretion process. Studies on the breakage of tolerance and induction of autoantibodies to these autoantigens could benefit SS patients. To break tolerance, we utilized a PmE-L peptide derived from the AQP5-homologous aquaporin of Prevotella melaninogenica (PmAqp) that contained both a B cell “E” epitope and a T cell epitope. Repeated subcutaneous immunization of C57BL/6 mice with the PmE-L peptide efficiently induced the production of Abs against the “E” epitope of mouse/human AQP5 (AQP5E), and we aimed to characterize the antigen specificity, the sequences of AQP5Especific B cell receptors, and salivary gland phenotypes of these mice. Sera containing anti-AQP5E IgG not only stained mouse Aqp5 expressed in the submandibular glands but also detected PmApq and PmE-L by immunoblotting, suggesting molecular mimicry.Characterization of the AQP5E-specific autoantibodies selected from the screening of phage display Ab libraries and mapping of the B cell receptor repertoires revealed that the AQP5E-specific B cells acquired the ability to bind to the Ag through cumulative somatic hypermutation. Importantly, animals with anti-AQP5E Abs had decreased salivary flow rates without immune cell infiltration into the salivary glands. This model will be useful for investigating the role of anti-AQP5 autoantibodies in glandular dysfunction in SS and testing new therapeutics targeting autoantibody production.

Background: We performed a prospective survey on the adverse reactions following the first dose of two types of vaccines against coronavirus disease 2019 (COVID-19) in healthcare workers (HCWs) in South Korea. Methods: HCWs at a tertiary referral hospital in Seoul, South Korea, received a chimpanzee adenovirus-vectored vaccine (ChAdOx1 nCoV-19) or an mRNA-based vaccine (BNT162b2) between March 5 and March 26, 2021. The HCWs were asked to report adverse reactions through a mobile self-report questionnaire for three days after vaccination. Results: A total of 7,625 HCWs received the first dose of ChAdOx1 or BNT162b2 vaccine during the study period. Of them, 5,866 (76.9%) HCWs (ChAdOx1, n = 5,589 [95.3%];BNT162b2, n = 277 [4.7%]) participated at least once in the survey, of whom 77% were female and 86% were younger than 50 years. The overall adverse reaction rate was 93% in the ChAdOx1 group and 80% in the BNT162b2 group (P < 0.001). Both local and systemic reactions were more commonly reported in the ChAdOx1 group, and the difference was larger in systemic reactions such as fever and fatigue. In the ChAdOx1 group, the incidence of adverse reactions was significantly higher in females and those in the younger age groups, while the BNT162b2 group showed such difference according to age. Conclusion In our prospective survey, vaccine-associated adverse reactions were more commonly reported in the ChAdOx1 group than in the BNT162b2 group. Females and younger age groups experienced vaccine-associated adverse reactions more frequently.

In a 3-year-old Samoyed, aortic bulging was found on radiography during a general check-up. On echocardiography, turbulent flow was found in left ventricular outflow tract (LVOT) with high velocity (6.1 m/s). A linear structure was attached to the interventricular septum and connected to the chordae tendineae reaching the papillary muscle. A part of the structure moved during cardiac cycle, similar to mitral motion. This dog was diagnosed with LVOT obstruction caused by accessory mitral valve tissue (AMVT). This is the first report of AMVT in veterinary medicine. AMVT should be considered as a possible cause of LVOT obstruction in dogs.

Background: We performed a prospective survey on the adverse reactions following the first dose of two types of vaccines against coronavirus disease 2019 (COVID-19) in healthcare workers (HCWs) in South Korea. Methods: HCWs at a tertiary referral hospital in Seoul, South Korea, received a chimpanzee adenovirus-vectored vaccine (ChAdOx1 nCoV-19) or an mRNA-based vaccine (BNT162b2) between March 5 and March 26, 2021. The HCWs were asked to report adverse reactions through a mobile self-report questionnaire for three days after vaccination. Results: A total of 7,625 HCWs received the first dose of ChAdOx1 or BNT162b2 vaccine during the study period. Of them, 5,866 (76.9%) HCWs (ChAdOx1, n = 5,589 [95.3%];BNT162b2, n = 277 [4.7%]) participated at least once in the survey, of whom 77% were female and 86% were younger than 50 years. The overall adverse reaction rate was 93% in the ChAdOx1 group and 80% in the BNT162b2 group (P < 0.001). Both local and systemic reactions were more commonly reported in the ChAdOx1 group, and the difference was larger in systemic reactions such as fever and fatigue. In the ChAdOx1 group, the incidence of adverse reactions was significantly higher in females and those in the younger age groups, while the BNT162b2 group showed such difference according to age. Conclusion In our prospective survey, vaccine-associated adverse reactions were more commonly reported in the ChAdOx1 group than in the BNT162b2 group. Females and younger age groups experienced vaccine-associated adverse reactions more frequently.

In a 3-year-old Samoyed, aortic bulging was found on radiography during a general check-up. On echocardiography, turbulent flow was found in left ventricular outflow tract (LVOT) with high velocity (6.1 m/s). A linear structure was attached to the interventricular septum and connected to the chordae tendineae reaching the papillary muscle. A part of the structure moved during cardiac cycle, similar to mitral motion. This dog was diagnosed with LVOT obstruction caused by accessory mitral valve tissue (AMVT). This is the first report of AMVT in veterinary medicine. AMVT should be considered as a possible cause of LVOT obstruction in dogs.