Determination of the Sugar Content in High-Sugar Beverages.

We determined the sugar content of 75 samples, including eight black sugar beverages (BSBs) and seven Dalgona lattes (DLs) from Seoul, Korea, using high-performance liquid chromatography-evaporative light scattering detector. The mean sugar content per 100 g was 12.7 g and 12.3 g for BSB and DL, respectively. According to the World Health Organization, the mean sugar content per serving in BSB and DL were 34.8 g and 32.5 g, respectively, equivalent to 65∼70% of the recommended daily intake for added sugars. The highest sugar was sucrose (56.5% in BSB and 64.4% in DL). The sugar content could be adjusted in 27 out of 40 stores for BSB and 25 out of 35 stores for DL. The relative standard deviation of the content (g/100 g) per store by the manufacturer ranged between 5.7∼21.6% for BSB and 2.3∼29.5% for DL. This suggests that a uniform recipe is required for manufacturing beverages.

Ecological Risk Assessment of Amoxicillin, Enrofloxacin, and Neomycin: Are Their Current Levels in the Freshwater Environment Safe?

Veterinary pharmaceuticals may cause unexpected adverse effects on non-target aquatic species. While these pharmaceuticals were previously identified as priority compounds in ambient water, their ecological risks are relatively unknown. In this study, a series of chronic toxicity tests were conducted for these pharmaceuticals using algae, two cladocerans, and a fish. After a 21-d exposure to amoxicillin, enrofloxacin, and neomycin, no observed effect concentration (NOEC) for the reproduction of Daphnia magna was detected at 27.2, 3.3, and 0.15 mg/L, respectively. For the survival of juvenile Oryzias latipes following the 40-d exposure, NOEC was found at 21.8, 3.2, and 0.87 mg/L, respectively. Based on the results of the chronic toxicity tests and those reported in the literature, predicted no-effect concentrations (PNECs) were determined at 0.078, 4.9, and 3.0 µg/L for amoxicillin, enrofloxacin, and neomycin, respectively. Their hazard quotients (HQs) were less than 1 at their average levels of occurrence in ambient freshwater. However, HQs based on the maximum detected levels of amoxicillin and enrofloxacin were determined at 21.2 and 6.1, respectively, suggesting potential ecological risks. As the potential ecological risks of these veterinary pharmaceuticals at heavily contaminated sites cannot be ignored, hotspot delineation and its management are required.

Hyperpolarized [1-13C] pyruvate MR spectroscopy detect altered glycolysis in the brain of a cognitively impaired mouse model fed high-fat diet.

Higher dietary intakes of saturated fatty acid increase the risk of developing Alzheimer's disease and dementia, and even in people without diabetes higher glucose levels may be a risk factor for dementia. The mechanisms causing neuronal dysfunction and dementia by consuming high-fat diet degrading the integrity of the blood-brain barrier (BBB) has been suggested but are not yet fully understood, and metabolic state of the brain by this type of insult is still veiled. The objective of this study was to investigate the effect of high-fat diet on the brain metabolism by a multimodal imaging method using the hyperpolarizedcarbon 13 (13C)-pyruvate magnetic resonance (MR) spectroscopy and dynamic contrast-enhanced MR imaging in conjunction with the biochemical assay and the behavior test in a mouse model fed high-fat diet (HFD). In mice were fed 60% HFD for 6 months, hyperpolarized [1-13C] pyruvate MR spectroscopy showed decreased perfusion (p < 0.01) and increased conversion from pyruvate to lactate (p < 0.001) in the brain. The hippocampus and striatum showed the highest conversion ratio. The functional integrity of the blood-brain barrier tested by dynamic contrast-enhanced MR imaging showed no difference to the control. Lactate was increased in the cortex (p < 0.01) and striatum (p < 0.05), while PDH activity was decreased in the cortex (p < 0.01) and striatum (p < 0.001) and the phosphorylated PDH was increased in the striatum (p < 0.05). Mice fed HFD showed less efficiency in learning memory compared with control (p < 0.05). To determine whether hyperpolarized 13C-pyruvate magnetic resonance (MR) spectroscopy could detect a much earier event in the brain. Mice fed HFD for 3 months did not show a detectable cognitive decline in water maze based learning memory. Hyperpolarized [1-13C] pyruvate MR spectroscopy showed increased lactate conversion (P < .001), but no difference in cerebral perfusion. These results suggest that the increased hyperpolarized [1-13C] lactate signal in the brain of HFD-fed mice represent that altered metabolic alteration toward to glycolysis and hypoperfusion by the long-term metabolic stress by HFD further promote to glycolysis. The hyperpolarized [1-13C] pyruvate MR spectroscopy can be used to monitor the brain metabolism and will provide information helpful to understand the disease process.

Assessment of Cognitive Impairment in a Mouse Model of High-Fat Diet-Induced Metabolic Stress with Touchscreen-Based Automated Battery System.

Obesity-related metabolic disorders can affect not only systemic health but also brain function. Recent studies have elucidated that amyloid beta deposition cannot satisfactorily explain the development of Alzheimer's disease (AD) and that dysregulation of glucose metabolism is a critical factor for the sporadic onset of non-genetic AD. Identifying the pathophysiology of AD due to changes in brain metabolism is crucial; however, it is limited in measuring changes in brain cognitive function due to metabolic changes in animal models. The touchscreen-based automated battery system, which is more accurate and less invasive than conventional behavioral test tools, is used to assess the cognition of mice with dysregulated metabolism. This system was introduced in humans to evaluate cognitive function and was recently back-translated in monkeys and rodents. We used outbred ICR mice fed on high-fat diet (HFD) and performed the paired associates learning (PAL) test to detect their visual memory and new learning ability loss as well as to assess memory impairment. The behavioral performance of the HFD mice was weaker than that of normal mice in the training but was not significantly associated with motivation. In the PAL test, the average number of trials completed and proportion of correct touches was significantly lower in HFD mice than in normal diet-fed mice. Our results reveal that HFD-induced metabolic dysregulation has detrimental effects on operant learning according to the percentage of correct responses in PAL. These findings establish that HFD-induced metabolic stress may have an effect in accelerating AD-like pathogenesis.

Determination of matrix effects occurred during the analysis of organochlorine pesticides in agricultural products using GC-ECD.

Matrix effects observed during the multiresidue analysis of seven organochlorine pesticides in six different agricultural products with GC-ECD were assessed. The presence of matrix coextractives, a major cause of observed matrix effects, directly and/or indirectly influenced the chromatographic responses of some pesticides. Two types of external calibrations, solvent calibration (SC) and matrixmatched calibration (MC), were used to assess matrix effects. Greater matrix effects were observed at the lower concentrations of each pesticide. The extent of matrix effects varied unpredictably with matrix type. Among the analyzed pesticides, iprodione, cyhalothrin, and cypermethrin exhibited greater matrix effects (>150%) for almost all matrices. The pesticide recovery rates obtained with MC were not statistically different from a 100% recovery rate in most samples, which indicates that MC may diminish the overestimates occurred due to matrix effects in GC analysis.

Ecotoxicological assessment of cimetidine and determination of its potential for endocrine disruption using three test organisms: Daphnia magna, Moina macrocopa, and Danio rerio.

Cimetidine is a histamine H2-receptor antagonist used for treatment of gastrointestinal disorders. It is often detected in aquatic environments, but its ecotoxicological effects have not been well studied. Thus, ecotoxicity of cimetidine was evaluated using Daphnia magna and Moina macrocopa, and zebrafish (Danio rerio), and a predicted no effect concentration (PNEC) was derived. In D. magna, 48 h immobilization EC50 was determined at 394.9 mg L(-1). However, reproduction damages in D. magna were not found even at the maximum exposure level (30 mg L(-1)). For M. macrocopa, 48 h EC50 was found at 175.8 mg L(-1) and the 7 d reproduction no observed effect concentration (NOEC) was 1.1 mg L(-1). For D. rerio, 40 d growth NOEC was determined at 100 mg L(-1), the highest experimental concentration. The PNEC of cimetidine was estimated at 0.1 mg L(-1) based on M. macrocopa 7d reproduction NOEC. In 14 d adult zebrafish exposure, endocrine disruption potentials of cimetidine were observed. In male, decrease in plasma 17ß-estradiol and testosterone levels, up-regulation of gonadal cyp17, and down-regulation of hepatic erα were observed at 300 mg L(-1). In female, increase in plasma E2 level and down-regulation of hepatic cyp1a were noted at 3 mg L(-1). Endocrine disruption effects were also observed in early life stage exposure. Up-regulation of erß at 17d, and cyp19a and vtg at 40 d post fertilization were detected at 100 mg L(-1), and co-occurrence of ovary and putative testis was observed at as low as 1.1 mg L(-1). The results indicate that there is little evidence for cimetidine to cause direct ecological impact at the current ambient levels in the aquatic environment. However potential consequences of endocrine disruption following long-term exposure in aquatic environment deserves further investigation.

Urinary phthalate metabolites among elementary school children of Korea: sources, risks, and their association with oxidative stress marker.

Phthalates have been used in a variety of consumer products and hence frequently been detected in humans. Children are susceptible to endocrine disrupting chemicals such as phthalates, but only limited information is available on the sources of exposure and potential adverse health effects among children. In this study, elementary school students (n=39, aged 9-12 years) were recruited in Seoul, and first void urine samples were collected twice in three-day intervals. Then six phthalate metabolites were analyzed by high performance liquid chromatography with triple quadrupole tandem mass spectrometry. In addition, malondialdehyde (MDA) as an oxidative stress marker was measured. A questionnaire was conducted and information on food consumption and the use of plastic packaging or storage materials was gathered. The concentrations of phthalate metabolites varied substantially by sampling time even within the same subject, but all target metabolites were detected in 100% of the samples with the highest geometric mean of 107 µg/g-creatinine for mono-n-butyl phthalate (MnBP). Urinary levels of mono-isobutyl phthalate (MiBP), and MnBP among Korean children were 8 and 3 times greater than those reported for US children, but those of monoethyl phthalate (MEP) were about 5 times lower than those of US children. Estimated phthalate intakes were generally in safe range, but in 3-8% of the participating children, the hazard quotients greater than one were noted. Urinary MDA concentrations were significantly associated with several metabolite levels after adjusting covariates in regression model. Consumption of dairy products or meat, and use of a plastic material were significantly associated with the DEHP metabolites or MnBP levels in multivariate model. The results of this study provide evidence of the association between phthalate exposure and oxidative stress especially among the early teenagers, and identified major sources that can be applied to development of management plan for phthalate exposure among children.

Effects of non-steroidal anti-inflammatory drugs on hormones and genes of the hypothalamic-pituitary-gonad axis, and reproduction of zebrafish.

This study was conducted in two experiments, to identify non-steroidal anti-inflammatory drugs (NSAIDs) with high endocrine disruption potentials, and to understand consequences of exposure to such NSAIDs in fish. In the first experiment, the effects of five NSAIDs on hormones and gene transcriptions of the hypothalamic-pituitary-gonad (HPG) axis were evaluated after 14 d exposure of adult zebrafish. Ibuprofen and mefenamic acids were identified to increase the concentrations of 17ß-estradiol and testosterone in females significantly, while decreased those of testosterone among male fish. Significant up-regulation of fshß, lhß, fshr and lhr were observed in females, whereas down-regulation was observed in males exposed to each NSAID. In the second experiment, ibuprofen was chosen as a model chemical. Adult zebrafish pairs were exposed to ibuprofen for 21 d, and the effects on reproduction and development of offspring were examined. The egg production was significantly decreased at ≥1 µg/L ibuprofen, and parental exposure resulted in delayed hatching even when they were transferred to clean water for hatching. The results demonstrated that ibuprofen could modulate hormone production and related gene transcription of the HPG axis in a sex-dependent way, which could cause adverse effects on reproduction and the development of offspring.

Urinary levels of N-acetyl-S-(2-carbamoylethyl)-cysteine (AAMA), an acrylamide metabolite, in Korean children and their association with food consumption.

Acrylamide (AA), a probable human carcinogen, is present in high-temperature-processed foods, and has frequently been detected in humans worldwide. In the present study, the levels of a major AA metabolite, N-acetyl-S-(2-carbamoylethyl)-cysteine (AAMA) were measured in urine samples collected in two separate events with 3d interval from Korean children (n=31, 10-13 years old), and their diets were surveyed for 4d period prior to the second urine sampling. Daily AA intake was estimated from AAMA urinary levels and the influence of food consumption on urinary AAMA levels was investigated. The concentrations of metabolite AAMA in urine ranged between 15.4 and 196.3 ng/mL, with a median level of 68.1 ng/mL, and the levels varied by day considerably even in a given child. Children who were exposed to environmental smoke at home exhibited significantly higher levels of AAMA in urine, suggesting the importance of passive smoking as a source of AA exposure among children. Median (95th percentile) values of daily AA intake in Korean children were 1.04 (2.47)µg/kgbodyweight/day, which is higher than those reported elsewhere. After adjustment for gender, body mass index, and smoking status of family members, the consumptions of cracker and chocolate were identified to be significantly associated with the concentrations of AAMA in urine. The result of this study will provide information useful for developing public health and safety management for AA.