Diabetes is well established as a chronic disease with a high health burden due to mortality or morbidity from the final outcomes of vascular complications. An increased duration of hyperglycemia is associated with abnormal metabolism. Advanced glycation end products (AGEs) are nonenzymatic glycated forms of free amino acids that lead to abnormal crosslinking of extra-cellular and intracellular proteins by disrupting the normal structure. Furthermore, the interaction of AGEs and their receptors induces several pathways by promoting oxidative stress and inflammation. In this review, we discuss the role of AGEs in diabetic vascular complications, especially type 2 DM, based on recent clinical studies.

Background: Sleep duration is an identified risk factor for adverse health outcomes. As the endocrine system is closely intertwined with sleep duration and quality, the association between endocrine dysfunction and sleep has been evaluated. Thyroid function, particularly that related to thyrotropin (TSH), is also known to be influenced by the sleep/awake status and circadian rhythm. Additionally, a link between sleep duration and autoimmunity, which is a common cause of thyroid dysfunction, has been suggested; however, depending on the sleep deprivation method used in studies, the effects of sleep on thyroid function vary. The relationship between subclinical thyroid dysfunction and sleep duration is poorly documented. Thus, to elucidate the impact of sleep on thyroid function, we investigated the association of subclinical thyroid dysfunction with sleep duration using representative data from the sixth Korea National Health and Nutrition Examination Survey, conducted from 2013 to 2015. Methods: In all, 4945 participants (2543 male and 2402 female) were included after excluding subjects using the following criteria: <19 years of age, free T4 level outside the normal range, history of thyroid disease, or incomplete data. The population was classified into three groups: short sleeper (8 h/day). The odds ratio (OR) for subclinical hypothyroidism or hyperthyroidism according to sleep duration was evaluated. Results: The short, normal, and long sleeper groups consisted of 2097, 2514, and 334 subjects, respectively. On multiple logistic regression analysis, compared to normal sleepers, short sleepers showed a significantly increased risk of subclinical hyperthyroidism (OR 1.37, 95% confidential interval (CI) 1.02–1.84, p = 0.036), while the risk of subclinical hypothyroidism in short sleepers was not elevated. Comparing long sleepers to normal sleepers, the OR for subclinical hyperthyroidism and hypothyroidism was 1.79 (95% CI 1.12–2.86, p = 0.015) and 1.91 (95% CI 1.03–3.53, p = 0.039), respectively. Conclusions: Both shorter and longer sleep durations were associated with an increase in the risk of subclinical thyroid dysfunction compared to the optimal sleep duration. This analysis of representative population data shows that sleep duration could intertwine with thyroid function resulting in increased risk of subclinical thyroid dysfunction.

Non-alcoholic fatty liver disease (NAFLD) is a prevalent liver disease encompassing a broad spectrum of pathologic changes in the liver. Metabolic derangements are suggested to be main causes of NAFLD. As thyroid hormone is a main regulator of energy metabolism, there may be a link between NAFLD and thyroid function. In previous studies, the association between NAFLD and thyroid function was not conclusive. The aim of this study was to clarify the relationship between NAFLD and thyroid function, focusing on subclinical hypothyroidism, using nationwide survey data representing the Korean population. NAFLD was defined as a hepatic steatosis index of 36 or higher. Based on the analysis of nationwide representative data, subclinical hypothyroidism was related to a high risk of NAFLD in males, but not in females. Our study showed that thyroid function might play a substantial role in the development of NAFLD, especially in males. Further study to elucidate the underlying mechanism of gender specific association of mild thyroid dysfunction and NAFLD would be required.

Background: We investigated whether the contralateral suppression index in aldosterone-producing adrenal adenoma could be used as a diagnostic criterion when catheterization in either right or left adrenal vein fails or when a discrepancy in the adrenal vein sampling (AVS) results and imaging findings occurs in the real-world practice.Methods: We retrospectively reviewed 48 patients who had resistant hypertension (HTN) or hypokalemia with a biochemical diagnosis of primary aldosteronism and who underwent AVS from January 2009 to June 2017 at a tertiary referral hospital. Selection index (SI), lateralization index (LI), and contralateral suppression index (CSI) were calculated based on AVS results and the final clinical outcomes were evaluated.Results: The catheterization of both adrenal veins was successful in 43 of 48 (89.6%) patients. The lateralization based only on LI was performed in 23 out of 43 (53.5%) patients. When CSI and LI were combined in decision making, the concordance between adrenal computed tomography scan and AVS for unilateral lesion improved from 59.3% (19/32) to 75.0% (24/32). CSI also correlated well with unilateral adrenal disease in the catheterization failure group. The final outcomes of HTN were better in the contralateral suppression group.Conclusion: CSI combined with LI could be a supplementary diagnostic tool in patients with non-lateralization or catheterization failure and predict the clinical outcomes of HTN in patients with primary aldosteronism.

Fine needle aspiration cytology (FNAC) and washout thyroglobulin (Tg) measurements are the standard for evaluating a metastatic lymph node (LN) in thyroid cancer. However, patients rarely benefit from these procedures due to false results. This study aims to identify a reliable biomarker that significantly improves the diagnosis of metastatic LNs, in addition to FNAC and washout Tg. This study analyzed 130 LNs that were suspected to have metastases on thyroid ultrasonography, from June 2016 to December 2017. All subjects underwent FNAC, washout Tg measurements and a new biomarker, washout Cytokeratin fragment 21-1 (CYFRA 21-1) measurement. The final LN outcomes were confirmed by surgical histology, repeat FNAC, or follow-up image. The diagnostic values of the presence of washout CYFRA 21-1 for diagnosing metastatic LNs were evaluated according to final LN outcomes. Among the 130 LNs, 42 were metastatic lesions and 88 were benign. The washout CYFRA 21-1 levels were significantly higher in metastatic LNs than in benign LNs. In contrast to the findings of washout Tg, washout CYFRA 21-1 showed little overlap between benign and malignant LNs, and its diagnostic cutoff values were not affected by surgery. The combinations of FNAC and washout CYFRA 21-1 showed higher sensitivity (91.9%), specificity (96.5%), negative predictive value (98.8%), and diagnostic accuracy (94.2%) than FNAC with washout Tg. The combination of FNAC, washout Tg, and washout CYFRA 21-1 showed the best sensitivity (98.8%). When washout CYFRA 21-1 was applied to the discordant results that were observed between FNAC and washout Tg, 20 of 22 LNs were correctly diagnosed. Washout CYFRA 21-1 measurements in thyroid LNs provide a diagnostic modality.