Kyoungho Lee

Clinical characteristics and risk factors of colistin-induced nephrotoxicity.

Since multidrug-resistant gram-negative organisms have been increasing, polymyxin E (colistin) has been reintroduced despite its nephrotoxicity. A case-control study was performed to investigate the incidence, clinical characteristics and risk factors of colistin-induced nephrotoxicity. From August 2006 to June 2008, 47 cases receiving at least one defined daily dose (DDD) of intravenous colistin were included; 15 (31.9%) of the 47 cases developed nephrotoxicity with preserved urine output, 3 (20%) of whom underwent renal replacement therapy. The mean dosage of colistimethate sodium was 2.25 g (22.5 DDD; range 0.6-8.7 g) at the time of nephrotoxicity. Of 10 patients who were re-assessed for renal function after 1 month, 9 (90%) recovered their renal function. In the univariate analysis, site of infection, hypoalbuminaemia and cumulative dosage of the second-generation fluoroquinolones, aminoglycosides and non-steroidal anti-inflammatory drugs (NSAIDs) co-administered during colistin treatment as well as concomitant use of NSAIDs were risk factors for nephrotoxicity. However, in the logistic regression hypoalbuminaemia and the use of NSAIDs were significant risk factors for increased nephrotoxicity during colistin administration, suggesting that free colistin might cause renal toxicity. In conclusion, colistin-induced nephrotoxicity occurred at a high rate, and hypoalbuminaemia and concomitant use of NSAIDs were significant risk factors.

Serum VEGF levels in acute ischaemic strokes are correlated with long‐term prognosis

Background and purpose:  We investigated whether serum vascular endothelial growth factor (VEGF) levels in acute‐stage ischaemic stroke patients with small vessel disease (SVD) or large vessel disease (LVD) are correlated with long‐term prognoses, based on the difference in NIH Stroke Scale (NIHSS) scores between acute and chronic stages.

Polycyclic aromatic hydrocarbon (1-OHPG and 2-naphthol) and oxidative stress (malondialdehyde) biomarkers in urine among Korean adults and children.

Using the urinary biomarkers 1-hydroxypyrene-glucuronide (1-OHPG), 2-naphthol, and malondialdehyde (MDA), we evaluated seasonal and regional variations in polycyclic aromatic hydrocarbon (PAH) exposure and oxidative stress among Korean adults and children. In total, 322 children (175 male and 147 female) and 332 adults (47 male and 285 female) were recruited in two regions of Korea, one representing a metropolitan area (Seoul/Incheon) and the other an industrial (Pohang) area, from winter 2002 to spring 2003. The subjects voluntarily gathered their first morning urine void, which was immediately transported to our laboratory and stored at -20 °C. Urinary 1-OHPG was measured by synchronous fluorescence spectroscopy, 2-naphthol by HPLC, and urinary MDA by HPLC with a UV detector. The median urinary 1-OHPG concentration tended to be higher in the industrial region than in the metropolitan region (0.92 vs. 0.77 ng/mL; p=0.03), and higher in winter than in spring (0.95 vs. 0.73 ng/mL; p<0.001). The median 2-naphthol concentration was also higher in the industrial region than in the metropolitan region (21.0 vs. 12.3 ng/mL; p<0.0001), but was higher in spring than in winter (19.7 vs. 10.3 ng/mL; p<0.0001). The median MDA concentration was significantly higher in winter than in spring (2.19 vs. 1.03 μmol/L; p<0.0001), whereas regional variation in MDA was observed only in female adults (p=0.02). In winter, the level of 1-OHPG was higher in children exposed to environmental tobacco smoke than in unexposed children (0.94 vs. 0.86 ng/mL; p=0.02). Our results indicate that both region and season can significantly influence the levels of PAH exposure and oxidative stress biomarkers.

Microbleeds and free active MMP-9 are independent risk factors for neurological deterioration in acute lacunar stroke.

Background and purpose:  In this prospective study, we evaluated mutual relationships amongst microbleeds, matrix metalloproteinase‐9 (MMP‐9) and neurological deterioration in patients with their first acute lacunar stroke.

Simultaneous Exposure to Heavy Metals among Residents in the Industrial Complex: Korean National Cohort Study.

A survey was conducted to evaluate the multi-exposure level and correlation among toxic metal biomarkers (Cd, Pb, and Hg). A total of 592 individuals who participated in the survey were residents near an industrial complex in Gwangyang and Yeosu (exposed group) and of Hadong and Namhae (control group) in southern Korea from May 2007 to November 2010. The Gwangyang and Yeosu area exposed groups had slightly higher blood Pb (2.21 and 1.90 µg/dL), urinary Cd observed values (2.20 and 1.46 µg/L), urinary Cd with a urinary creatinine correction (1.43 and 1.25 µg/g Cr), and urinary Hg observed values (2.26 and 0.98 µg/L) in women participants than those in the Hadong and Namhae area (control group). Blood Pb (3.18 and 2.55 µg/dL), urinary Hg observed values (1.14 and 0.92 µg/L), and urinary Hg with a urinary creatinine correction (1.06 and 0.96 µg/L) for male participants were also slightly higher than those in the Hadong and Namhae area (control group). The correlation among urinary Cd, Hg and Pb concentrations in the blood was significant. We suggest that the exposed group of residents were simultaneously exposed to Pb, Cd, and Hg from contaminated ambient air originating from the iron manufacturing industrial complex.

A longitudinal study of atrazine and 2,4‐D exposure and oxidative stress markers among iowa corn farmers

Reactive oxygen species, potentially formed through environmental exposures, can overwhelm an organisms antioxidant capabilities resulting in oxidative stress. Long‐term oxidative stress is linked with chronic diseases. Pesticide exposures have been shown to cause oxidative stress in vivo. We utilized a longitudinal study of corn farmers and non‐farming controls in Iowa to examine the impact of exposure to the widely used herbicides atrazine and 2,4‐dichlorophenoxyacetic acid (2,4‐D) on markers of oxidative stress. 225 urine samples were collected during five agricultural time periods (pre‐planting, planting, growing, harvest, off‐season) for 30 farmers who applied pesticides occupationally and 10 controls who did not; all were non‐smoking men ages 40–60. Atrazine mercapturate (atrazine metabolite), 2,4‐D, and oxidative stress markers (malondialdehyde [MDA], 8‐hydroxy‐2′‐deoxyguanosine [8‐OHdG], and 8‐isoprostaglandin‐F2α [8‐isoPGF]) were measured in urine. We calculated β estimates and 95% confidence intervals (95%CI) for each pesticide‐oxidative stress marker combination using multivariate linear mixed‐effect models for repeated measures. Farmers had higher urinary atrazine mercapturate and 2,4‐D levels compared with controls. In regression models, after natural log transformation, 2,4‐D was associated with elevated levels of 8‐OHdG (β = 0.066, 95%CI = 0.008–0.124) and 8‐isoPGF (β = 0.088, 95%CI = 0.004–0.172). 2,4‐D may be associated with oxidative stress because of modest increases in 8‐OHdG, a marker of oxidative DNA damage, and 8‐isoPGF, a product of lipoprotein peroxidation, with recent 2,4‐D exposure. Future studies should investigate the role of 2,4‐D‐induced oxidative stress in the pathogenesis of human diseases. Environ. Mol. Mutagen. 58:30–38, 2017.

Increasing risk of diabetes mellitus according to liver function alterations in electronic workers

We sought to determine the association between change in fasting plasma glucose (FPG) and levels of liver enzymes, such as aspartate transaminase, alanine transaminase and gamma‐glutamyltransferase, from health examinations.

Retraction note: Assessment of human biomonitoring and DNA microarray analysis in the vicinity population on an industrial complex

The purpose of this study was to assess current exposure of the population living in the Gwangyang industrial complex and other areas to heavy metals and, VOCs and to identify individual factors associated with urinary and blood levels of these chemicals. The study population was made up of 810 participants ranging in age from 7 to 87 years old at Gwangyang bay in the South Korea. The selected biomarkers represent the main agents to which a population like that of Korean is exposed every day, including 4 heavy metals in blood or urine (Pb in blood and As, Cd, Hg in urine), and VOCs in blood descriptive data analysis leads to mean concentrations of heavy metals, As, Cd, Hg and Pb of 7.34 μg/g cr, 1.04 g/g cr, 1.33 μg/g cr and 2.53 μg/dL, respectively. The mean concentration of benzene, ethylbenzene, tetrachloroehylene, toluene, m-/p-xylene and o-xylene in blood were 0.00 μg/L, 0.00 μg/L, 0.00 μg/L, 0.03 μg/L, 0.00 μg/L and 0.00 μg/L, respectively. The DNA microarray analysis using blood of 16 participants, control group (n=6) and sample group (n=10), showed that the two groups might belong to a different group through hierarchical clustering the present study provides reference values for selected pollutants for the general population in industrial complexes, which can be used for comparison purposes in further studies, since they are mostly within the reference ranges reported by other biomonitoring studies therefore, it would be possible to devise standards for identifying the environmental pollution and beforehand forecast. In addition, it will be the one of the scientific method to help reduce anxiety of residents lived in the polluted areas.

Human Exposure Assessment of Airborne Pollutants for Residents in Gwangyang City Near Industrial Plants (I)

ObjectiveThe object of this study is to analyze metabolites of environmental chemicals and to identify possible health hazards to obtain reliable levels of exposure in Gwangyang city in the vicinity of a refinery and steel industrial complex in the year 2011-2012.MethodsParticipant age in each gender was significantly >59 years comprising more than 90% of the total participants and female participants were almost double males. Target metabolites included 21 chemicals of 3 heavy metals, 4 polycyclic aromatic hydrocarbons (PAHs), 7 volatile organic compounds (VOCs), 5 phthalates and creatinine.ResultsWe found some interesting points of comparison. The geometric mean values of metabolites in control area were similar to or slightly higher overall than those in the exposed area. Some metabolites, such as urinary (U)-Hg and organic metabolites like VOCs, PAHs and phthalates, significantly showed higher concentrations in the control area. Whilst their highest (max.) values for three metabolites (U-m-methylhippuric acid (MHA), U-p-MHA and U-monobenzyl phthalate) in the exposed was always higher than the control. Moreover U-Cadmium, U-2-Naphtol and U-ttmuconic acid (MA) in the exposed area far exceeded the national average and average of 50+ age group. Interesting gender-specific differences in three VOC metabolites (U-t,t-MA, U-hippuric acid (HA), U-mandelic acid (MA) (female specific, females>males) and blood (B)-lead (Pb) (male specific, males>females) were seen, and were always higher in males or females in both areas. Accordingly, the present study indicates that heavy metals and VOCs appear to be the most noteworthy pollutants that may cause adverse health effects in the human population near Gwangyang city.ConclusionIn conclusion, observed metabolite levels did not exceed health-based reference values and/or guidelines available. Nevertheless, continuing biomonitoring surveillance is necessary to watch on hazardous air pollutants (HAPs) to protect public health in industrial sites.

349 Alterations of Clinical biomarkers on Pre and Post Exercise in Obese Electronic Workers

Objectives The purpose of this study was to compare the pre and post-exercise clinical indicators levels such as γ-GTP, ALT, AST, total cholesterol, LDL-cholesterol, HDL-cholesterol, triglyceride, fasting blood sugar (FBS) and HbA1C among obese electronic workers. Methods Subjects were 26 obese workers whose average age was 31.75 year old with body mass index value over 30 kg/m2. All subjects were participated in physical exercise and diet programs during 15 weeks. Measures of clinical biomarkers such as liver function enzymes, cholesterol and diabetes indicators, blood pressure, body composition were all obtained before and after the exercise. All subjects participated in the study and gave written informed consent. Each participant completed a brief questionnaire. All data are represented as mean ± standard deviation and paired t-tests were done to compare biomarkers means between pre and post exercise. Results The average weight showed a significant difference between before and after weight loss (95.67 ± 9.05 vs 89.36 ± 9.53 kg). Clinical liver function indicators were significantly improved after 15 weeks (ex. γ-GTP (p < 0.01), ALT (p < 0.01) and AST (p = 0.01)). Levels of total cholesterol (p < 0.01), LDL-cholesterol (p < 0.01) and triglyceride showed a significant decrease after weight loss, however HDL-cholesterol was higher levels in after exercise. And, Fasting blood sugar (p < 0.01) and HbA1C levels (p < 0.01) were significantly decreased by reduction of body weight after 15 weeks exercise. Conclusions In conclusion, after 15 weeks combined exercise and low calorie diet programs, body composition was improved. Liver function enzymes, diabetes biomarkers and total cholesterol were significantly decreased after weight loss. These data suggest that exercise is an effective health promotion strategy for liver function, diabetes indicators and lipid profile in obese workers.