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In this paper, we analyze the outage performance of Unmanned Aerial Vehicles (UAVs)-enabled downlink Non-Orthogonal Multiple Access (NOMA) communication systems with the Semi-Grant-Free (SGF) transmission scheme. A UAV provides coverage services for a Grant-Based (GB) user and one Grant-Free (GF) user is allowed to utilize the same channel resource opportunistically. The analytical expressions for the exact and asymptotic Outage Probability (OP) of the GF user are derived. The results demonstrate that no-zero diversity order can be achieved only under stringent conditions on users' quality of service requirements. Subsequently, an efficient Dynamic Power Allocation (DPA) scheme is proposed to relax such data rate constraints. The analytical expressions for the exact and asymptotic OP of the GF user with the DPA scheme are derived. Finally, Monte Carlo simulation results are presented to validate the correctness of the derived analytical expressions and demonstrate the effects of the UAV's location and altitude on the OP of the GF user.

Treatment patterns and preferences for patients with Graves’ disease (GD) vary across countries. In this study, we assessed the initial therapies and subsequent treatment modalities employed for GD in real-world clinical practice in Korea. We analyzed 452,001 patients with GD from 2004 to 2020, obtained from the Korean National Health Insurance Service database. Initial treatments included antithyroid drug (ATD) therapy (98% of cases), thyroidectomy (1.3%), and radioactive iodine (RAI) therapy (0.7%). The rates of initial treatment failure were 58.5% for ATDs, 21.3% for RAI, and 2.1% for thyroidectomy. Even among cases of ATD treatment failure or recurrence, the rates of RAI therapy remained low. Regarding initial treatment, the 5-year remission rate was 46.8% among patients administered ATDs versus 91.0% among recipients of RAI therapy; at 10 years, these rates were 59.2% and 94.0%, respectively. Our findings highlight a marked disparity in the use of RAI therapy in Korea compared to Western countries. Further research is required to understand the reasons for these differences in treatment patterns.

BackgroundMounting evidence indicates the importance of the interplay between skeletal muscles and lipid metabolism. Remnant cholesterol (remnant-C) is considered one of the principal residual risk factors for cardiovascular disease and metabolic disorders; however, there are limited studies on the impact of remnant-C on sarcopenia.MethodsData from the Korea National Health and Nutrition Examination Surveys (KNHANES) between 2008 and 2011 were used in this nationwide population-based study. In total, 17,408 participants were enrolled in this study. The subjects were categorized into four groups according to the quartile of remnant-C values. We conducted multivariable logistic regression analysis to evaluate the association between remnant-C and muscle mass measured using dual-energy X-ray absorptiometry.ResultsA total of 1,791 participants (10.3%) presented low muscle mass, and there was a sequential increase in the percentage of low muscle mass across remnant-C quartiles (Q1, 5.2%; Q2, 8.7%; Q3, 11.5%; Q4, 15.7%). In the full adjusted model, those in the highest remnant-C quartile group showed significantly increased odds ratio (OR) for low muscle mass compared with those in the lowest remnant-C group after adjusting for various confounding factors (OR = 1.33, 95% confidence interval (CI) = 1.06–1.68, P

Novel strategies are required to reduce the risk of developing diabetes and/or clinical outcomes and complications of diabetes. In this regard, the role of the circadian system may be a potential candidate for the prevention of diabetes. We reviewed evidence from animal, clinical, and epidemiological studies linking the circadian system to various aspects of the pathophysiology and clinical outcomes of diabetes. The circadian clock governs genetic, metabolic, hormonal, and behavioral signals in anticipation of cyclic 24-hour events through interactions between a “central clock” in the suprachiasmatic nucleus and “peripheral clocks” in the whole body. Currently, circadian rhythmicity in humans can be subjectively or objectively assessed by measuring melatonin and glucocorticoid levels, core body temperature, peripheral blood, oral mucosa, hair follicles, rest-activity cycles, sleep diaries, and circadian chronotypes. In this review, we summarized various circadian misalignments, such as altered light-dark, sleep-wake, rest-activity, fasting-feeding, shift work, evening chronotype, and social jetlag, as well as mutations in clock genes that could contribute to the development of diabetes and poor glycemic status in patients with diabetes. Targeting critical components of the circadian system could deliver potential candidates for the treatment and prevention of type 2 diabetes mellitus in the future.

Background There was limited evidence to evaluate the association between lifestyle habits and continuous glucose monitoring (CGM) metrics. Thus, we aimed to depict the behavioral and metabolic determinants of CGM metrics in insulin-treated patients with type 2 diabetes mellitus (T2DM). Methods This is a prospective observational study. We analyzed data from 122 insulin-treated patients with T2DM. Participants wore Dexcom G6 and Fitbit, and diet information was identified for 10 days. Multivariate-adjusted logistic regression analysis was performed for the simultaneous achievement of CGM-based targets, defined by the percentage of time in terms of hyper, hypoglycemia and glycemic variability (GV). Intake of macronutrients and fiber, step counts, sleep, postprandial C-peptide-to-glucose ratio (PCGR), information about glucose lowering medications and metabolic factors were added to the analyses. Additionally, we evaluated the impact of the distribution of energy and macronutrient during a day, and snack consumption on CGM metrics. Results Logistic regression analysis revealed that female, participants with high PCGR, low glycosylated hemoglobin (HbA1c) and daytime step count had a higher probability of achieving all targets based on CGM (odds ratios [95% confidence intervals] which were 0.24 [0.09 to 0.65], 1.34 [1.03 to 1.25], 0.95 [0.9 to 0.99], and 1.15 [1.03 to 1.29], respectively). And participants who ate snacks showed a shorter period of hyperglycemia and less GV compared to those without. Conclusion We confirmed that residual insulin secretion, daytime step count, HbA1c, and women were the most relevant determinants of adequate glycemic control in insulin-treated patients with T2DM. In addition, individuals with snack consumption were exposed to lower times of hyperglycemia and GV.

Abstract Background Unhealthy body composition, including high fat mass, low muscle mass and low bone mass, is a critical health issue in adults. The weight‐adjusted waist index (WWI) estimates fat and muscle mass and may have implications for bone health. We examined its association with body composition outcomes in a large Korean adult cohort. Methods This study used data from the Korean National Health and Nutrition Examination Survey (2008–2011). WWI was calculated as waist circumference (cm) divided by the square root of body weight (kg). Dual‐energy X‐ray absorptiometry was used to measure bone mineral density (BMD), appendicular lean mass (ALM) and total body fat percentage. Unhealthy body composition was defined as combined presence of high fat mass, low bone mass and low muscle mass. Results A total of 5983 individuals (3034 men [50.7%] and 2949 women [49.3%]; mean age: 63.5 ± 8.7 years) were included. WWI was positively correlated with total body fat percentage (r = 0.478, P

Background We aimed to investigate the moderating effects of obesity, age, and sex on the association between sleep duration and the development of diabetes in Asians. Methods We analyzed data from a cohort of the Korean Genome and Epidemiology Study conducted from 2001 to 2020. After excluding shift workers and those with diabetes at baseline, 7,407 participants were stratified into three groups according to sleep duration: ≤5 hours/night, >5 to 7 hours/night (reference), and >7 hours/night. The Cox proportional hazards analyses were used to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) for incident type 2 diabetes mellitus (T2DM). Subgroup analyses were performed according to obesity, age, and sex. Results During 16 years of follow-up, 2,024 cases of T2DM were identified. Individuals who slept ≤5 h/night had a higher risk of incident diabetes than the reference group (HR, 1.17; 95% CI, 1.02 to 1.33). The subgroup analysis observed a valid interaction with sleep duration only for obesity. A higher risk of T2DM was observed in the ≤5 hours/night group in non-obese individuals, men, and those aged 7 hours/night group in obese individuals (HRs were 1.34 [95% CI, 1.11 to 1.61], 1.22 [95% CI, 1 to 1.49], and 1.18 [95% CI, 1.01 to 1.39], respectively). Conclusion This study confirmed the effect of sleep deprivation on the risk of T2DM throughout the 16-year follow-up period. This impact was confined to non-obese or young individuals and men. We observed a significant interaction between sleep duration and obesity.

BackgroundEffective health interventions for North Korean refugees vulnerable to metabolic disorders are currently unelucidated. ObjectiveThis study aimed to evaluate the effects of digital health interventions in North Korean refugees using a wearable activity tracker (Fitbit device). MethodsWe conducted a prospective, randomized, open-label study on North Korean refugees aged 19-59 years between June 2020 and October 2021 with a 12-week follow-up period. The participants were randomly assigned to either an intervention group or a control group in a 1:1 ratio. The intervention group received individualized health counseling based on Fitbit data every 4 weeks, whereas the control group wore the Fitbit device but did not receive individualized counseling. The primary and secondary outcomes were the change in the mean daily step count and changes in the metabolic parameters, respectively. ResultsThe trial was completed by 52 North Korean refugees, of whom 27 and 25 were in the intervention and control groups, respectively. The mean age was 43 (SD 10) years, and 41 (78.8%) participants were women. Most participants (44/52, 95.7%) had a low socioeconomic status. After the intervention, the daily step count in the intervention group increased, whereas that in the control group decreased. However, there were no significant differences between the 2 groups (+83 and –521 steps in the intervention and control groups, respectively; P=.500). The effects of the intervention were more prominent in the participants with a lower-than-average daily step count at baseline (

Abstract Atopic dermatitis (AD) has been increasing worldwide over the past few decades. AD has been reported to be associated with an increased risk of osteoporosis and fractures in adult AD patients. The aim of this study was to investigate the bone mineral density (BMD) to evaluate osteoporosis risk in young adults with AD by sex. This was a case–control cohort study using a national dataset from the Korea National Health and Nutrition Examination Survey 2007–2009. We included young adult AD patients (men aged 19 ≤ and

Background We investigated how 100-g oral glucose tolerance test (OGTT) results can be used to predict adverse pregnancy outcomes in gestational diabetes mellitus (GDM) patients. Methods We analyzed 1,059 pregnant women who completed the 100-g OGTT between 24 and 28 weeks of gestation. We compared the risk of adverse pregnancy outcomes according to OGTT patterns by latent profile analysis (LPA), numbers to meet the OGTT criteria, and area under the curve (AUC) of the OGTT graph. Adverse pregnancy outcomes were defined as a composite of preterm birth, macrosomia, large for gestational age, low APGAR score at 1 minute, and pregnancy-induced hypertension. Results Overall, 257 participants were diagnosed with GDM, with a median age of 34 years. An LPA led to three different clusters of OGTT patterns; however, there were no significant associations between the clusters and adverse pregnancy outcomes after adjusting for confounders. Notwithstanding, the risk of adverse pregnancy outcome increased with an increase in number to meet the OGTT criteria (P for trend=0.011); odds ratios in a full adjustment model were 1.27 (95% confidence interval [CI], 0.72 to 2.23), 2.16 (95% CI, 1.21 to 3.85), and 2.32 (95% CI, 0.66 to 8.15) in those meeting the 2, 3, and 4 criteria, respectively. The AUCs of the OGTT curves also distinguished the patients at risk of adverse pregnancy outcomes; the larger the AUC, the higher the risk (P for trend=0.007). Conclusion The total number of abnormal values and calculated AUCs for the 100-g OGTT may facilitate tailored management of patients with GDM by predicting adverse pregnancy outcomes.

Background To evaluate the association of time to reach the target glycosylated hemoglobin (HbA1c) level with long-term durable glycemic control and risk of diabetic complications in patients with newly diagnosed type 2 diabetes mellitus (T2DM). Methods In a longitudinal observational cohort, 194 patients with T2DM newly diagnosed between January 2011 and March 2013 were followed up over 6 years. Patients were classified according to the time needed to reach the target HbA1c (

Abstract Background Hypothyroidism, one of the prevalent endocrine disorders worldwide, has a broad spectrum of clinical manifestations, from an asymptomatic condition to myxedema coma. Although the majority of patients with hypothyroidism have minor clinical symptoms, which are recovered with levothyroxine treatment, some patients occasionally do experience fatal complications. Here we report, for the first time, the case of a patient who had hypothyroidism with simultaneous occurrence of rhabdomyolysis with acute kidney injury, moderate pericardial effusion, and sudden sensorineural hearing loss. Case presentation A 57-year-old man with a previous history of dyslipidemia and untreated hypothyroidism was admitted to the hospital due to shortness of breath, lethargy, lower extremity discomfort, and unilateral hearing loss. Laboratory results revealed rhabdomyolysis with acute kidney injury and severe hypothyroidism. We detected cardiomegaly without lung parenchymal infiltration on chest radiography and moderate pericardial effusion on transthoracic echocardiography. We performed pure tone audiometry and identified profound unilateral sensorineural hearing loss. Aggressive fluid resuscitation, levothyroxine treatment, and systemic and intratympanic steroid therapy alleviated the patient’s severe hypothyroidism, rhabdomyolysis, and pericardial effusion; however, sensorineural hearing loss was not fully recovered. Conclusions Early recognition of life-threatening complications is important in patients with severe hypothyroidism to prevent adverse outcomes. This case suggests that hypothyroidism should be considered in patients who have rhabdomyolysis with acute kidney disease and pericardial effusion. Moreover, sudden sensorineural hearing loss should be kept in mind as a rare complication of hypothyroidism.

Objective To investigate the prevalence of osteoporosis among North Korean women refugees when compared with South Korean women, who have identical genetic backgrounds but experience different environments.Design Comparative cross-sectional study.Setting North Korean Refugee Health in South Korea (NORNS) study in South Korea.Participants We evaluated 122 North Korean women who participated in NORNS study and 366 age-matched/menopausal status-matched South Korean women from the Korea University Medical Center (KUMC) health examination cohort. The median age of the NORNS participants was 46 years (IQR, 40–60 years) with 52 women (42.6%) being postmenopausal.Results Among the postmenopausal women, NORNS participants had a higher body mass index and number of pregnancies and lower physical activity than the KUMC participants. The overall prevalence of osteoporosis was 48% (25/52) and 17% (27/156) in NORNS and KUMC participants, respectively. The bone mineral density (BMD) values at the lumbar spine, femur neck and total hip were significantly lower in postmenopausal NORNS women than in the postmenopausal KUMC women. Old age, low body weight and late age of menarche were associated with low BMD among the postmenopausal North Korean refugees. In premenopausal participants, the NORNS women had lower body weight and physical activity than the KUMC women at baseline. All the NORNS women had normal Z-scores, although the BMD at the lumbar spine was significantly lower in NORNS women than in the KUMC women (0.952 vs 1.002 g/cm2, p

BackgroundPast decades of division have led to substantial differences in medical environments between South and North Korea. However, little is known about North Korea's medical status and research field, especially regarding endocrinology. In this study, we report the characteristics of North Korea's articles regarding endocrine-related diseases.MethodsAmong the nine medical journals, articles published in Internal Medicine between 2006 and 2015 were reviewed. A total of 2,092 articles were included; among them, 96 articles were associated with endocrinology. We analyzed these articles according to the disease categories they focused on and evaluated their features.ResultsArticles related to diabetes mellitus accounted for 55.2% (n=53) and those to thyroid disease accounted for 28.1% (n=27). Other disease categories, including adrenal gland (n=1), pituitary gland (n=1), and osteoporosis (n=3), comprised minor portions. Regarding diabetes mellitus, more than half the articles (n=33) focused on treatment and complications. Experimental studies were conducted with old hypoglycemic drugs or natural substances for the treatment of hyperglycemia. Regarding thyroid disease, articles related to hyperthyroidism were the most common (51.9%, n=14), followed by thyroid nodule/cancer (18.5%, n=5). Unique article features were short length, no figures, and less than five references.ConclusionNorth Korea's endocrinology articles mainly focused on diabetes mellitus and thyroid disease. Persistent studies have been carried out in North Korea with dedication despite the poor medical environment. We hope that this study will be the beginning of mutual medical exchange and collaboration between North and South Korea.

BackgroundTo estimate and compare the trends of all-cause and cause-specific mortality rates for subjects with and without diabetes in South Korea, from 2003 to 2013.MethodsUsing a population-based cohort (2003 to 2013), we evaluated annual mortality rates in adults (≥30 years) with and without diabetes. The number of subjects in this analysis ranged from 585,795 in 2003 to 670,020 in 2013.ResultsAge- and sex-adjusted all-cause mortality rates decreased consistently in both groups from 2003 to 2013 (from 14.4 to 9.3/1,000 persons in subjects with diabetes and from 7.9 to 4.4/1,000 persons in those without diabetes). The difference in mortality rates between groups also decreased (6.61 per 1,000 persons in 2003 to 4.98 per 1,000 persons in 2013). The slope associated with the mortality rate exhibited a steeper decrease in subjects with diabetes than those without diabetes (regression coefficients of time: −0.50 and −0.33, respectively; P=0.004). In subjects with diabetes, the mortality rate from cardiovascular disease decreased by 53.5% (from 2.73 to 1.27 per 1,000 persons, P for trend

BackgroundLong-term durable glycemic control is a difficult goal in the management of type 2 diabetes mellitus (T2DM). We evaluated the factors associated with durable glycemic control in a real clinical setting.MethodsWe retrospectively reviewed the medical records of 194 new-onset, drug-naïve patients with T2DM who were diagnosed between January 2011 and March 2013, and were followed up for >2 years. Glycemic durability was defined as the maintenance of optimal glycemic control (glycosylated hemoglobin [HbA1c]

Background : The survival benefit of excess body weight is controversial across various subpopulations. We assessed the effect of weight status on all-cause mortality among patients with type 2 diabetes (T2DM) undergoing subtotal gastrectomy for gastric cancer. Methods : Medical charts of 210 patients with T2DM treated at 2 university hospitals were examined retrospectively. All patients had undergone subtotal gastrectomy for cancer between January 1993 and December 2012. Participants were categorized as normal weight (body mass index [BMI], 18.5-24.99 kg/m²) or overweight/obese (BMI≥25 kg/m²). The association between weight status and all-cause mortality was assessed using weighted Cox proportional hazard regression models and inverse probability weighting. Results : The mortality rate was 25.2% after a median follow-up duration of 6.1 years (interquartile range, 3.5-8.3 years; maximum, 14.4 years). The overweight/obese group had a significantly lower risk of all-cause mortality (hazard ratio, 0.51; 95% confidence interval, 0.34-0.77; p=0.001) compared with the normal weight group. Overweight/obesity was associated with reduced all-cause mortality in patients aged

BackgroundGlycemic variability is associated with the development of diabetic complications through the activation of oxidative stress. This study aimed to evaluate the effects of a dipeptidyl peptidase 4 inhibitor, vildagliptin, or a thiazolidinedione, pioglitazone, on glycemic variability and oxidative stress in patients with type 2 diabetes.MethodsIn this open label, randomised, active-controlled, pilot trial, individuals who were inadequately controlled with metformin monotherapy were assigned to either vildagliptin (50 mg twice daily, n=17) or pioglitazone (15 mg once daily, n=14) treatment groups for 16 weeks. Glycemic variability was assessed by calculating the mean amplitude of glycemic excursions (MAGE), which was obtained from continuous glucose monitoring. Urinary 8-iso prostaglandin F2α, serum oxidised low density lipoprotein, and high-sensitivity C-reactive protein were used as markers of oxidative stress or inflammation.ResultsBoth vildagliptin and pioglitazone significantly reduced glycated hemoglobin and mean plasma glucose levels during the 16-week treatment. Vildagliptin also significantly reduced the MAGE (from 93.8±38.0 to 70.8±19.2 mg/dL, P=0.046), and mean standard deviation of 24 hours glucose (from 38±17.3 to 27.7±6.9, P=0.026); however, pioglitazone did not, although the magnitude of decline was similar in both groups. Markers of oxidative stress or inflammation including urinary 8-iso prostaglandin F2α did not change after treatment in both groups.ConclusionIn this 16-week treatment trial, vildagliptin, but not pioglitazone, reduced glycemic variability in individuals with type 2 diabetes who was inadequately controlled with metformin monotherapy, although a reduction of oxidative stress markers was not observed.

Wheat germ (WG) is a by-product of wheat milling and comprises many bioactive compounds. This study aimed to compare the antioxidant and antilipidemic effects of different WG extracts (WGEs) by analyzing candidate bioactive compounds such as carotenoids, tocopherols, γ-oryzanol, and biogenic amines by reversed-phase high-performance liquid chromatography. Antioxidant activity was determined using the ABTS, DPPH, and FRAP assays. The antilipidemic effect was evaluated in palmitic acid-induced steatosis in HepG2 hepatocytes and 3T3-L1 adipocytes. Cellular lipid accumulation was assessed by Oil Red O staining and a cellular triglyceride content assay. All analyzed WGEs showed significant antioxidant potential, although some bioactive compounds, such as carotenoids, tocopherols, and γ-oryzanol, were the highest in the ethanol extract. Correlation analysis revealed the antioxidant potential of all identified biogenic amines except for spermidine. Ethanol and n-hexane extracts significantly inhibited cellular lipid accumulation in cell models. These results suggest that WGEs exhibit promising antioxidant potential, with a variety of bioactive compounds. Collectively, the findings of this study suggest that bioactive compounds in WGEs attenuate plasma lipid and oxidation levels. In conclusion, WG can be used as a natural antioxidant and nutraceutical using appropriate solvents and extraction methods.

This study aimed to compare the anti-inflammatory activity of 10-year-old Dendropanax morbifera LEV (DM) leaf extracts. The leaves were collected during different seasons (May, August, and November), and the extracts were prepared using different methods (hot water, 30% ethanol, or 60% ethanol). Lipopolysaccharide-stimulated RAW264.7 cells were treated with these extracts for 12 h. The anti-inflammatory effects were evaluated by measuring the production of nitrite; prostaglandin E2 (PGE2); and inflammatory cytokines such as interleukin (IL)-6, IL-1β, and tumor necrosis factor-alpha, in addition to the mRNA expression levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 and activation of the nuclear factor κB (NF-κB)/mitogen-activated protein kinase (MAPK) pathways. The amyrin and polyphenol compositions of the extracts were analyzed using a triple time-of-flight mass spectrometer and high-performance liquid chromatography. The 30% ethanol extract harvested in May and 60% ethanol extracts collected in August and November displayed the highest inhibitions of nitrite, PGE2, and inflammatory cytokines. The 60% ethanol extract harvested in August suppressed activation of the NF-κB and MAPK signaling pathways. The contents of amyrin and polyphenol compounds were highly dependent on the ethanol concentration used during each season. These results suggest that ethanol extracts of DM leaves may have the potential to regulate inflammatory responses.

This study aimed to determine the effect of deep-sea water (DSW)-derived mineral waters on intestinal health, using a cell model and a dextran sulfate sodium (DSS)-induced enteritis mouse model. DSW was desalted and minerals were added to generate mineral waters that were classified as trace mineral (TM), high magnesium (HM), high magnesium low salt (HMLS), and high magnesium high calcium (HMHC), using a tabletop electrodialysis device. Caco-2 cells cocultured with Raw264.7 cells were either pre-treated or not with the four water groups, and inflammation was induced by treatment with lipopolysaccharide (LPS). Compared to LPS-treated Caco-2 cells, HMLS-cotreated cells maintained high transepithelial electrical resistance, similar to control cells. FITC-dextran permeability was lower in HMLS-treated than in other cells. In vivo, in comparison to DSS-treated mice, colon shortening was inhibited, and disease activity and colon injury were suppressed in HMLS-cotreated mice. RNA-seq of colonic tissues revealed that inflammatory gene expression was similar among the control and HMLS mice, and DSS-induced expression of inflammation-related genes such as TNF-α and NOS2 and inflammatory chemokine genes was suppressed. Our findings suggest that DSW-derived mineral water intake can help reduce colitis symptoms, and the effects may be partially regulated by magnesium and other minerals.

Red ginseng has been widely used in health-promoting supplements in Asia and is becoming increasingly popular in Western countries. However, its therapeutic mechanisms against most diseases have not been clearly elucidated. The aim of the present study was to provide the biological mechanisms of red ginseng against various metabolic diseases. We used a systems biological approach to comprehensively identify the component-target and target-pathway networks in order to explore the mechanisms underlying the therapeutic potential of red ginseng against metabolic diseases. Of the 23 components of red ginseng with target, 5 components were linked with 37 target molecules. Systematic analysis of the constructed networks revealed that these 37 targets were mainly involved in 9 signaling pathways relating to immune cell differentiation and vascular health. These results successfully explained the mechanisms underlying the efficiency of red ginseng for metabolic diseases, such as menopausal symptoms in women, blood circulation, diabetes mellitus, and hyperlipidemia.