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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. Public concern regarding the deterioration of the surrounding environment has been raised aiming at the enormous infected animal carcass burials. On behalf of the Ministry of Environment (ME) of the Korean government, we conducted groundwater monitoring at approximately 3000 wells around the burial sites for 7 years from 2011 to 2017. The baseline groundwater already had enriched levels of nitrogen and chloride compounds masking the influence of leachate with the pre-existing anthropogenic contamination. Based on the trend analysis, most monitoring wells had no significant trends in NO 3 -N and Cl implying that an abrupt degradation in water quality was not expected across the country. Increasing proportions of total coliform detection in the groundwater of the majority of provinces will cause potential damage to human health around the carcass burial sites. Wells showing frequent upward and downward trends near the carcass burial pits were targeted for principal component analysis (PCA) and the results showed that NH 4 -N, TOC, Cl, and K could be indicators distinguishing the sole impacts of animal leachate on the groundwater. Analyses of the nationwide monitoring data indicated possibly delayed and prolonged impacts of the widespread burials of livestock mortalities on the groundwater environment. The finding provides realistic insight regarding how to manage the mass burial of livestock mortalities to protect groundwater resources. • Nationwide monitoring of groundwater quality near the FMD burial pits was conducted. • Temporal change in NO 3 -N, Cl, total coliforms was frequently observed near burial sites. • Statistic approaches can distinguish impact of animal leachate alone on groundwater. [ABSTRACT FROM AUTHOR]

Objectives This study sought to evaluate the long-term prognostic value of coronary computed tomography angiography (CTA) in asymptomatic patients with type 2 diabetes mellitus. Background There are limited data on the long-term prognostic impact of coronary CTA in asymptomatic patients with type 2 diabetes mellitus. Methods This study analyzed clinical outcomes of 591 consecutive asymptomatic patients with type 2 diabetes mellitus who underwent coronary CTA (mean age 62.2 ± 8.3 years and 352 men [59.6%]). A cardiac event was defined as a composite of cardiac death, nonfatal myocardial infarction, unstable angina requiring hospitalization, or late coronary revascularization. Patients were categorized into 3 groups according to severity of coronary artery disease (CAD) on coronary CTA: normal coronary arteries, nonobstructive CAD (<50%), and obstructive CAD (≥50%). Results One hundred sixty-eight patients (28.4%) had normal coronary arteries, whereas 236 (39.9%) patients had nonobstructive CAD and 187 (31.6%) had obstructive CAD. During the follow-up period (median 5.3 years [interquartile range: 4.7 to 5.8 years]), 37 cardiac events occurred in 29 patents: 10 cardiac deaths, 2 nonfatal myocardial infarctions, 8 cases of unstable angina, and 17 late coronary revascularizations. The 6-year event-free survival rates were 99.3 ± 0.7% in patients with normal coronary arteries, 96.7 ± 1.2% in patients with nonobstructive CAD, and 86.2 ± 3.0% in patients with obstructive CAD (log-rank p < 0.001). Conclusions Asymptomatic patients with type 2 diabetes mellitus with normal coronary arteries or nonobstructive CAD on coronary CTA show excellent clinical outcomes over a follow-up period of more than 5 years, whereas prognosis is worse in patients with obstructive CAD. These findings suggest long-term prognostic value of coronary CTA for asymptomatic type 2 diabetes mellitus. [ABSTRACT FROM AUTHOR]

Abstract: Obesity is rapidly increasing and is of great public health concern worldwide. Although there have been remarkable developments in obesity research over the past 10 years, the molecular mechanism of obesity is still not completely understood. Body weight results from the balance between food intake and energy expenditure. Recent studies have found that hypothalamic AMP-activated protein kinase plays a key role in regulating these processes. Leptin, insulin, glucose and alpha-lipoic acid have been shown to reduce food intake by lowering hypothalamic AMP-activated protein kinase activity, whereas ghrelin and glucose depletion increase food intake by increasing hypothalamic AMP-activated protein kinase activity. In addition, this enzyme plays a role in the central regulation of energy expenditure. These findings indicate that hypothalamic AMP-activated protein kinase is an important signal molecule, which integrates nutritional and hormonal signals and modulates feeding behavior and energy expenditure. [Copyright &y& Elsevier]

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. The concentrations of NO 3 –N in the groundwater ranged between 0.14 and 45.6 mg/L in August 2015 and 0.2–39.6 mg/L in March 2016. High concentrations of Cl− (388–1107 mg/L) and a high electrical conductivity (1027–2715 μS/cm) were observed in the study area, suggesting that the groundwater was affected by seawater intrusion. Furthermore, δ15N–NO 3 -, δ34S–SO 4 2- values and 87Sr/86Sr of groundwater were determined to reveal the origins of the natural and anthropogenic contaminants and the groundwater mean residence times (MRT) and 87Sr/86Sr ratios were used to assess the hydrogeochemical processes along the flow path in the study area. Young groundwater was affected by an anthropogenic contamination source with contributions of 26–46% adding nitrate to the aquifer, whereas old groundwater was impacted by mixing with seawater with contributions of 10–20% with low concentrations of NO 3 –N, but elevated concentrations of chloride and sulfate. Recently recharged uncontaminated groundwater showed oxic conditions with a diverse microbial community structure, whereas young groundwater contaminated by anthropogenic sources showed a less diverse microbial community structure. The results of this study suggest that multiple isotopes combined with groundwater MRT and microbial data can be applied to distinguish natural and anthropogenic contaminant sources in a groundwater system. Image 1 • Novel approaches were uses to differentiate anthropogenic and natural contaminant sources. • A Bayesian mixing model was used to determine contributions of contaminant sources. • Groundwater MRT and microbial data were evaluated to differentiate contaminant sources. • Multi-isotope, microbial data and MRT were combined to assess contaminant sources. Multi-isotope and microbial data combined with groundwater mean residence times successfully revealed the origins of natural and anthropogenic contaminants. [ABSTRACT FROM AUTHOR]

A recombinant Clostridium difficile expression system was used to produce genetically engineered toxoids A and B as immunogens for a prophylactic vaccine against C. difficile– associated disease. Although all known enzymatic activities responsible for cytotoxicity were genetically abrogated, the toxoids exhibited residual cytotoxic activity as measured in an in vitro cell-based cytotoxicity assay. The residual cytotoxicity was eliminated by treating the toxoids with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide. Mass spectrometry and amino acid analysis of the EDC-inactivated toxoids identified crosslinks, glycine adducts, and β-alanine adducts. Surface plasmon resonance analysis demonstrated that modifications resulting from the chemical treatment did not appreciably affect recognition of epitopes by both toxin A- and B-specific neutralizing monoclonal antibodies. Compared to formaldehyde-inactivated toxoids, the EDC/N-hydroxysuccinimide–inactivated toxoids exhibited superior stability in solution with respect to reversion of cytotoxic activity. [ABSTRACT FROM AUTHOR]

Abstract: Aims: Increased sugar consumption may adversely affect glycemic control in patients with diabetes. Although patients with diabetes are generally thought to prefer sweet tastes, few data are available on the sucrose preference in these individuals. The aim of the present study was to evaluate sucrose preference in patients with type 2 diabetes in comparison with subjects without diabetes. Methods: Sucrose preference was assessed in 200 subjects (100 type 2 diabetes patients and 100 age-, sex- and body mass index (BMI)-matched control subjects). Sucrose preference was evaluated together with sucrose perception (i.e., sucrose sensitivity). Clinical and biochemical factors affecting sucrose taste were also analyzed. Results: Participants with type 2 diabetes preferred lower sucrose concentrations compared with control subjects (p =0.001), although they had a less sensitive palate for sucrose compared with subjects without diabetes (p =0.012). Individual sucrose preference demonstrated a negative relationship with sensitivity to sucrose in control subjects. Notably, this relationship between sucrose preference and sensitivity was completely absent in participants with type 2 diabetes. Male patients with diabetes demonstrated a higher sucrose preference compared with female patients. There were no significant correlations between sucrose preference and glycemic control, duration of diabetes, or anti-diabetic medications. Conclusions: Participants with type 2 diabetes demonstrate a lower preference for sweet tastes than control subjects despite their decreased perception of sucrose. Reduced sucrose preference is not associated with better glycemic control in individuals with diabetes. [Copyright &y& Elsevier]

In Korea, where shallow weathered granitic aquifers are ubiquitous, several previous studies have reported strong radioactivity in shallow groundwater, which eventually led to the closure of production wells; however, no integrated study has analyzed factors controlling the spatial distribution of radionuclides in groundwater. Herein, we compiled the existing measurements of He, Ne, Ar, Kr, and Xe from 122 shallow wells (<200 m in depth) to differentiate and analyze the distribution of non-atmospheric (excess) 4He as a proxy for radionuclide accumulation in groundwater. The closed-system equilibration (CE) model accurately predicted the measured 4He in samples (root-mean-square deviation = 0.486), indicating its application in discerning the physical conditions of groundwater recharge in shallow granitic aquifers. Fifty-five samples were selected to identify the origin of strong radioactivity in shallow aquifers; low-quality samples were screened based on the (1) goodness of fit (>1%), (2) plausibility of modeled excess air concentrations (<0.05 cm3 STP/g), and (3) recharge temperature (5–20 °C). The distribution of excess He in the aquifers was largely dependent on the rock type, as defined by three distinct trends in He isotope excesses. Specifically, we observed (1) a large contribution of a mantle source of He isotopes, with values as high as ∼6.7 R A (R A = air = 1.39 × 10−6), on Jeju Island (quaternary basalt); (2) a small but significant contribution of mantle in Yanggu (Jurassic hornblende granite), with values up to 2.3 R A ; and (3) a purely radiogenic source of 4He (i.e., no mantle contribution) throughout the remaining five granitic or sedimentary aquifers. Moreover, the shallow aquifer in Wonju (Jurassic biotite granite) exhibited a measurable amount of excess He, without large faults. The radiogenic sources scattered in the shallow granite aquifer caused localized 4He concentration peaks, even in young groundwaters (1.6–19.9 y). The concentration of radioelements peaked at a relatively shallow depth of 18.5 m, refuting the diffusive supply of radionuclides from the external deep reservoir. This was attributed to the high range of 4He accumulation rates (3.51 × 10−9 to 1.17 × 10−8 cm3STP/g/y), which originated from the high in-situ production of residual soils weathered from U-abundant protolith. The present study demonstrated that excess He quantified using the CE model can help identify the origin of strong radioactivity in shallow groundwater. • CE model accurately predicts the measured 4He (RMSD = 0.550). • Excess He was detected in shallow granitic aquifer without large faults. • 4He peaks were detected in young groundwaters of 1.6–19.9 y. • Vertical 4He profile refuted the external and diffusive supply of radionuclides. • Abundant 4He originated from shallow residual soils produced in-situ from granite. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to examine the possible association between serum ceruloplasmin, a copper carrying protein, and albuminuria in 456 males with type 2 diabetes. Multivariate regression analysis demonstrated that elevated serum ceruloplasmin was a determinant of albuminuria independently of conventional risk factors. [Copyright &y& Elsevier]