Nitrate sources, timing, and pathways of a permeable volcanic aquifer system with mixed land use in Jeju Island, South Korea.

The occurrence of various N-related human activities increases the difficulty in distinguishing the major sources of NO contamination in groundwater, especially in areas with mixed land uses. In addition, the estimation of the timing and pathways of NO is necessary to better understand the processes of NO contamination in the subsurface aquifer system. This study applied environmental tracers, such as stable isotopes and age tracers (δN and δO of NO, δB, chlorofluorocarbons, and H), to elucidate the sources, timing, and pathways of NO contamination in the groundwaters of the Hanrim area, which has suffered from illegal disposal of livestock wastes since the 1980s, and also characterizes them based on mixed N-contaminant sources such as chemical fertilizers and sewage.

Impact of abdominal obesity on the risk of glioma development in patients with diabetes: A nationwide population-based cohort study in Korea.

Background: Abdominal obesity has been suggested as a risk factor for glioma; however, it is unclear whether this association applies to people with diabetes. This study examined the association between abdominal obesity and the risk of developing gliomas in diabetic patients.

Methods: We conducted a retrospective cohort study using the National Health Insurance System of South Korea from 2009 to 2012.

Integrated application of a Bayesian mixing model, numerical model, and environmental tracers to characterize groundwater recharge sources in a mountainous area.

In this study, the combined use of a Bayesian mixing model (BMM), numerical model (random walk particle tracking-RWPT), and environmental tracers (δO-δD, H, and CFC) was applied to elucidate the probabilistic contribution of the recharge sources, flow path, and residence time of groundwater across the mountainous area of Jeju Island, South Korea. Especially, the BMM ability to estimate the variable recharge contributions to the aquifer by different elevations and seasons was investigated. The δO-δD isotopes showed that groundwater in the study area was primarily fed by precipitation during the wet season, and the BMM estimated that wet season recharge contributed to approximately 64% of the total.

Association between organochlorine pesticides and nonalcoholic fatty liver disease in the National Health and Nutrition Examination Survey 2003-2004.

While endocrine disruptors are emerging as a cause of nonalcoholic fatty liver disease (NAFLD), little is known about the link between NAFLD and organochlorine pesticides (OCPs), one of the endocrine disruptors. We retrospectively analyzed the U.S.

Hepatic promotes nonalcoholic fatty liver disease by suppressing .

Background: Non-alcoholic fatty liver disease (NAFLD) is characterized by excessive lipid accumulation and imbalances in lipid metabolism in the liver. Although nuclear receptors (NRs) play a crucial role in hepatic lipid metabolism, the underlying mechanisms of NR regulation in NAFLD remain largely unclear.

Methods: Using network analysis and RNA-seq to determine the correlation between NRs and microRNA in human NAFLD patients, we revealed that specifically targets mimic and anti- were administered to human HepG2 and Huh-7 cells and mouse primary hepatocytes as well as high-fat diet (HFD)- or methionine-deficient diet (MCD)-fed mice to verify the specific function of in NAFLD.

Sphingosine 1-Phosphate Receptor 4 Promotes Nonalcoholic Steatohepatitis by Activating NLRP3 Inflammasome.

Background & Aims: Sphingosine 1-phosphate receptors (S1PRs) are a group of G-protein-coupled receptors that confer a broad range of functional effects in chronic inflammatory and metabolic diseases. S1PRs also may mediate the development of nonalcoholic steatohepatitis (NASH), but the specific subtypes involved and the mechanism of action are unclear.

Methods: We investigated which type of S1PR isoforms is activated in various murine models of NASH.

Perilipin 5 is a novel target of nuclear receptor LRH-1 to regulate hepatic triglycerides metabolism.

Liver receptor homolog-1 (LRH-1) has emerged as a regulator of hepatic glucose, bile acid, and mitochondrial metabolism. However, the functional mechanism underlying the effect of LRH-1 on lipid mobilization has not been addressed. This study investigated the regulatory function of LRH-1 in lipid metabolism in maintaining a normal liver physiological state during fasting.

Delineation of groundwater quality locations suitable for target end-use purposes through deep neural network models.

Groundwater is the main source of water for beverages, and its quality varies depending on extraction location; this is particularly the case in regions with complex geology, topography, and multiple forms of land use. Thus, it is important to determine a suitable groundwater extraction location based on intended water use and the related water quality standards. In this study, deep neural network (DNN) models and GIS data relating to groundwater quality were applied to estimate potential maps of Gangwon Province in South Korea, where groundwater is frequently extracted for drinking purposes.

Differentiation of natural and anthropogenic contaminant sources using isotopic and microbial signatures in a heavily cultivated coastal area.

Hydrogeochemical and multiple isotope data for groundwater samples were obtained and interpreted to discriminate anthropogenic and natural contaminant sources in a coastal aquifer underlying a heavily cultivated watershed in Hwaseong, South Korea. The local aquifers are vulnerable to contamination, due to high anthropogenic N inputs and the location close to the ocean facilitating seawater intrusion. Thus, to effectively control the groundwater quality in the study area, it is necessary to differentiate between anthropogenic and natural contaminant sources.

Sphingomyelin synthase 1 mediates hepatocyte pyroptosis to trigger non-alcoholic steatohepatitis.

Objective: Lipotoxic hepatocyte injury is a primary event in non-alcoholic steatohepatitis (NASH), but the mechanisms of lipotoxicity are not fully defined. Sphingolipids and free cholesterol (FC) mediate hepatocyte injury, but their link in NASH has not been explored. We examined the role of free cholesterol and sphingomyelin synthases (SMSs) that generate sphingomyelin (SM) and diacylglycerol (DAG) in hepatocyte pyroptosis, a specific form of programmed cell death associated with inflammasome activation, and NASH.

Insulin Resistance Increases Serum Immunoglobulin E Sensitization in Premenopausal Women.

Background: Although studies have shown that obesity is associated with aeroallergen sensitization (atopy), controversy still exists. We aimed to investigate the association between metabolic status, obesity, and atopy stratified by sex and menopausal status.

Methods: A total of 1,700 adults from the 2010 Korean National Health and Nutrition Examination Survey were classified into metabolically healthy nonobese (MHNO), metabolically unhealthy nonobese (MUNO), metabolically healthy obese (MHO), and metabolically unhealthy obese (MUO) by body mass index and insulin resistance.

Mitophagy deficiency increases NLRP3 to induce brown fat dysfunction in mice.

Although macroautophagy/autophagy deficiency causes degenerative diseases, the deletion of essential autophagy genes in adipocytes paradoxically reduces body weight. Brown adipose tissue (BAT) plays an important role in body weight regulation and metabolic control. However, the key cellular mechanisms that maintain BAT function remain poorly understood.

Application of geographically weighted regression models to predict spatial characteristics of nitrate contamination: Implications for an effective groundwater management strategy.

Groundwater nitrate contamination has been the main water quality problem threatening the sustainable utilization of water resources in Jeju Island, South Korea. The spatially varying distribution of nitrate levels associated with complex environmental and anthropogenic factors has been a major challenge restricting improved groundwater management. In this study, we applied ordinary least squares (OLS) regression and geographically weighted regression (GWR) models to determine the relationships between the NO-N concentration and various parameters (topography, hydrology and land use) across the island.

Impact of Diabetes Control on Subclinical Atherosclerosis: Analysis from Coronary Computed Tomographic Angiography Registry.

Background: There are limited data on the impact of diabetes control on the risk of subclinical coronary atherosclerosis.

Methods: We analyzed 6,434 consecutive asymptomatic individuals without previous history of coronary artery disease who underwent coronary computed tomographic angiography (CCTA) (mean age, 53.7±7.

Inhibition of Ceramide Accumulation in Podocytes by Myriocin Prevents Diabetic Nephropathy.

Background: Ceramides are associated with metabolic complications including diabetic nephropathy in patients with diabetes. Recent studies have reported that podocytes play a pivotal role in the progression of diabetic nephropathy. Also, mitochondrial dysfunction is known to be an early event in podocyte injury.

Autophagic flux defect in diabetic kidney disease results in megamitochondria formation in podocytes.

Podocyte injury is an important factor in the pathogenesis of diabetic nephropathy. Podocytes are characterized by large numbers of mitochondria. However, mitochondrial dysfunction as it relates to kidney pathology remains poorly understood.

Impaired Peroxisomal Fitness in Obese Mice, a Vicious Cycle Exacerbating Adipocyte Dysfunction Oxidative Stress.

Peroxisome is a critical organelle for fatty acid oxidation (FAO) and metabolism of reactive oxygen species (ROS). Increased oxidative stress in adipose tissue contributes to the development of insulin resistance and metabolic syndrome in obesity. This study aimed to investigate the role of peroxisomal fitness in maintaining adipocyte function, which has been under-rated in the obesity research area.

Nationwide groundwater monitoring around infectious-disease-caused livestock mortality burials in Korea: Superimposed influence of animal leachate on pre-existing anthropogenic pollution.

A foot-and-mouth disease (FMD) outbreak during 2010 affected the entire country of South Korea and approximately 3.4 million swine and bovine mortalities were disposed of at approximately 4800 on-farm burial sites for a few months following the first outbreak. Furthermore, outbreaks of avian influenza (AI) have struck Korea consistently since 2014.

Mitochondrial Dysfunction in Adipocytes as a Primary Cause of Adipose Tissue Inflammation.

Adipose tissue inflammation is considered a major contributing factor in the development of obesity-associated insulin resistance and cardiovascular diseases. However, the cause of adipose tissue inflammation is presently unclear. The role of mitochondria in white adipocytes has long been neglected because of their low abundance.

Association between diabetes and asthma: Evidence from a nationwide Korean study.

Background: Type 2 diabetes and asthma share a common pathophysiology: "chronic inflammation." However, it is unclear whether patients with type 2 diabetes are at increased risk of asthma.

Objective: To investigate the effect of type 2 diabetes on asthma using data from a large population-based study in Korea.

miR-30a Remodels Subcutaneous Adipose Tissue Inflammation to Improve Insulin Sensitivity in Obesity.

Chronic inflammation accompanies obesity and limits subcutaneous white adipose tissue (WAT) expandability, accelerating the development of insulin resistance and type 2 diabetes mellitus. MicroRNAs (miRNAs) influence expression of many metabolic genes in fat cells, but physiological roles in WAT remain poorly characterized. Here, we report that expression of the miRNA in subcutaneous WAT corresponds with insulin sensitivity in obese mice and humans.

Association Between Diabetic Retinopathy and Parkinson Disease: The Korean National Health Insurance Service Database.

Context: Studies have shown an association between diabetes and Parkinson disease (PD). The retina is a part of the central nervous system; it was proposed that diabetic retinopathy (DR) and PD share common pathophysiology of dopamine deficiency. However, no epidemiologic studies have investigated the relationship between these two diseases.