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Our research team investigated the elemental composition and the presence of various toxic organic compounds, such as polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), in estuary surface sediments to trace the spatial distribution of the sources of pollution deposited in Nakdong River, Busan, South Korea. The spatial patterns of elemental composition and toxic organic compounds were determined from the measurements of total organic carbon (TOC), total nitrogen, total sulfur, PAHs, and PCBs. The sediments had TOC contents of between 0.02 and 1.80 wt% (avg. 0.34 wt%), depending on the amount of clay-sized particles. The concentrations of PAHs and PCBs (10.8–167.7 ng g−1dry wt and 197.0–754.0 pg g−1dry wt, respectively) in surface sediments revealed different spatial patterns for these compounds, suggesting that they partially originated from the combustion of fossil fuels and from the use of commercial PCB products at adjacent industrial complexes. Although these concentrations were far below the Sediment Quality Guideline (SQG) of the National Oceanic and Atmospheric Administration (NOAA), the sediments at one site contained PCBs at concentrations close to the response level (754.0 pg g−1dry wt), and were dominated by low-molecular-weight PAHs. The PAHs and PCBs in Nakdong River Estuary sediments were likely to have originated from the combustion of fossil fuels and biomass at the adjacent industrial complexes. The primarily analyzed results determined that PAHs originated from the combustion of fossil fuels and biomass, and overall concentrations were related to the contributions of individual PAHs in most sediment samples. Based on the SQG of the NOAA, our results indicate that the anthropogenic activity should be considered on the future-sustainable management of this estuary system. [ABSTRACT FROM PUBLISHER]

Objective: To (i) test whether atomoxetine is non-inferior to methylphenidate in treating symptoms of attention deficit hyperactivity disorder (ADHD) in paediatric patients; and (ii) determine the tolerability of the two drugs. Method: This double-blind study was conducted in 6- to 16-year-old outpatients with ADHD (DSM-IV) in China, Korea and Mexico (January-October 2004). Patients were randomly assigned to once-daily atomoxetine (0.8-1.8 mg kg-1 day-1; n = 164) or twice-daily methylphenidate (0.2-0.6 mg kg-1 day-1; n = 166) for ∼8 weeks. Primary efficacy assessment was the comparison of response rates (≥40% reduction from baseline to end point in total score) on the Attention Deficit Hyperactivity Disorder Rating Scale-IV-Parent Version: Investigator-Administered and -Scored. Tolerability measures included, but were not limited to, the assessment of treatment-emergent adverse events (TEAEs) and weight. Results: Atomoxetine was non-inferior to methylphenidate in improving ADHD symptoms based on response rates (atomoxetine, 77.4%; methylphenidate, 81.5%; one-sided 95% lower confidence limit = -11.7%, p = 0.404). Treatment-emergent adverse effects experienced significantly more frequently in the atomoxetine group, compared with the methylphenidate group, included anorexia (37.2% vs. 25.3%; p = 0.024), nausea (20.1% vs. 10.2%; p = 0.014), somnolence (26.2% vs. 3.6%; p <0.001), dizziness (15.2% vs. 7.2%; p = 0.024) and vomiting (11.6% vs. 3.6%; p = 0.007), most of which were of mild or moderate severity. Atomoxetine-treated patients experienced a small but significantly greater mean weight loss from baseline to end point than methylphenidate-treated patients (-1.2 kg vs. -0.4 kg; p <0.001). Conclusions: This study suggests that atomoxetine is non-inferior to methylphenidate in the improvement of ADHD symptoms in paediatric outpatients. Although both of the drugs were well tolerated, atomoxetine was associated with a higher incidence of TEAEs than methylphenidate. [ABSTRACT FROM AUTHOR]

Background: Little is known about the clinical characteristics of patients with situational syncope such as defecation syncope (DS) or micturition syncope (MS) compared with those with common vasovagal syncope (VVS). Methods: Among 680 consecutive patients, who underwent a head-up tilt test between January 2006 and November 2010, 282 patients (40.4± 16.7 years; 48.6% men) diagnosed as DS (n = 38), MS (n = 38), or common VVS (n = 208) were included. Results: Ages at diagnosis (38.7± 17.3 vs 48.3± 14.1 vs 42.0± 13.8, P = 0.004) and the first syncope (33.7± 18.4 vs 44.5± 15.3 vs 37.5± 14.6, P = 0.002) were significantly less in patients with common VVS than those with DS or MS, respectively. The patients with MS were more likely to be men (73.7%, P = 0.036), whereas patients with DS were more commonly women (73.7%). No sexual preference was observed in patients with common VVS. Body mass index was significantly lower (P = 0.047) and syncopal episodes were more recurrent (P = 0.049) in patients with common VVS than those with DS or MS. The frequency of drinking alcohol before syncope was significantly higher in patients with MS (39.5%, P < 0.001). Conclusions: DS tended to occur in older women, whereas MS tended to occur in middle-aged men and drinking alcohol was an important precipitating factor for MS. However, common VVS was observed more in a thin and young population, which was more recurrent compared with those situational syncopes. (PACE 2011;1-7) [ABSTRACT FROM AUTHOR]

Background and Aims: The eradication rate of proton-pump inhibitor-based triple therapy for Helicobacter pylori infection is low due to increasing antibiotics resistance, especially clarithromycin. Recently, it was reported in Europe that a 10-day sequential strategy produced good outcomes. The aim of this study was to assess the efficacy of sequential therapy as first-line treatment for eradication of H. pylori in clinical practice in Korea. Materials and Methods: A total of 98 patients (mean age 55.2 years and male 47, female 51) with proven H. pylori infection received 10-day sequential therapy (20 mg of rabeprazole, and 1 g of amoxicillin, twice daily for the first 5 days, followed by 20 mg of rabeprazole, 500 mg of clarithromycin, and 500 mg of metronidazole, twice daily for the remaining 5 days). Eradication was evaluated 4 weeks later, after completion of treatment by 13C-urea breath testing. Eradication rates were calculated by intention-to-treat (ITT) and by per protocol (PP). Compliance and adverse events were also assessed in study group. Results: The eradication rate of sequential therapy was 91.8% (90/98) by ITT and same result was reported by PP analysis (89/97). The study group consisted of 66 H. pylori associated gastritis, 7 gastric ulcer, and 25 duodenal ulcer patients (67.3%, 7.1%, 25.5%, respectively). Mild adverse events happened frequently (21.4%) but the treatment was well tolerable. The most common adverse event was a bitter taste (9.2%) followed by nausea and diarrhea (4.1%). Conclusions: Ten-day sequential therapy is found to effectively eradicate H. pylori infection as first-line treatment in Korea. [ABSTRACT FROM AUTHOR]

Purpose — This study seeks to investigate the effect of mobile number portability (MNP) on mobile subscribers in Korea by focusing on subscribers' perception and behavior related to MNP Design/methodology/approach — The study collected data on subscribers who had changed mobile carriers between the beginning of MNP (July 2003) and December 2005. The data were analyzed by statistical analyses such as ANOVA and logistic regression. Findings — Statistical analyses in this study reveal that subscribers perceive the switching barrier still as high, discouraging subscribers from switching carriers. While MNP lowered switching costs considerably, a significant level of switching costs still remains despite MNP Carriers develop new subscriber lock-in strategies that make them stay with current carriers. In addition, there are hidden costs other than MNP that should burden subscribers with number portaling. Research limitations/implications — The findings imply that the MNP has directly affected the industries to a greater extent than subscribers, which suggests implications for both regulators and industries: how to effectively enforce MNP to achieve the intended goals and how to achieve competitive advantage with MNP Originality/value — This research is particularly interested in investigating the effect of the introduction of MNP on subscribers' behaviors and perceptions, and therefore their motivations for changing or remaining with mobile carriers (operators) with the introduction of MNP Although there have been many studies looking at the effect of number portability on competition at the industry level, little attention has been shown on the individual level such as subscribers' behavior or perception. [ABSTRACT FROM AUTHOR]

Abstract: This paper examines the prospectus of Digital Multimedia Broadcasting from the technical, economic and regulatory issues. This paper attempts to gain a better understanding of how DMB will evolve and stabilize in next generation network environments. Two research questions guide this study: (1) How does DMB trigger a change in policy, market and industry structure? (2) What are the driving forces of the rapid DMB development in Korea? As these questions involve socio-technical issues, this study uses a socio-technical perspective to investigate the complex relations between the social and technical aspects of DMB by highlighting the co-evolving nature, diversity, and interface between different driving forces and policy. The finding is that Korean DMB is the outcome of a proactive strategy of a telecom carrier and the Korean government''s industrial policy to support such strategy. Among the push-oriented trajectory, however, non-technical issues such as users, market and regulation are left behind, which reveals the disjunction of the DMB development in terms of the socio-technical system perspective. The development of DMB sheds light on the growing challenges in the dynamics of industry, regulation, and technology. [Copyright &y& Elsevier]

Purpose: To evaluate the efficacy and safety of photorefractive keratectomy (PRK) with intraoperative application of mitomycin-C (MMC). Setting: Yonsei Eye Center, Seoul, South Korea. Methods: This retrospective noncomparative case series included 536 patients (1011 eyes) who had had PRK with intraoperative application of MMC using the Nidek EC-5000 excimer laser. Preoperative and postoperative best spectacle-corrected and uncorrected visual acuities, spherical equivalent (SE) refraction, corneal haze graded by slitlamp biomicroscopy, and endothelial cell density measured by specular microscopy were evaluated. Results: The mean preoperative SE was −7.82 diopters (D) ± 2.64 (SD); 72% of eyes (732) were more than −6.00 D, and 28% (287) were more than −9.00 D. The mean follow-up was 13 months (range 6 to 27 months). Six months postoperatively, the mean postoperative SE was −0.14 ± 0.62 D; 86% were within ±0.50 D and 93% were within ±1.00 D of desired refraction. Eighty-six percent had 20/20 or better visual acuity, and 98% were 20/40 or better. Regression of more than 1.00 D occurred in 78 eyes (7.6%), and it was more common in eyes with a preoperative SE of −9.00 D or worse (18%). Haze occurred in 32 eyes (3.17%), but in most cases it was limited to grade 1. Grades 2 and 3 haze occurred in 3 eyes and 2 eyes, respectively. The postoperative endothelial cell density measured by specular microscopy did not show a significant difference from preoperative measurements. Delayed epithelial healing was observed in 2 eyes. Conclusion: Photorefractive keratectomy with intraoperative application of MMC was a safe procedure that produced excellent visual outcomes with few complications. [Copyright &y& Elsevier]

Background and Aims: Resistance rates of Helicobacter pylori to clarithromycin, metronidazole, and quinolone are over 30% in South Korea. The aim of this prospective study was to evaluate the ultimate eradication rate of H. pylori after first, second, or third-line therapy in Korea., Methods: A cohort of 2202 patients with H. pylori was treated with proton pump inhibitor (PPI)-based triple therapy for seven days. In case of treatment failure or recurrence, moxifloxacin-based triple therapy (MA) or bismuth-based quadruple therapy (QUAD) was randomly given. When the second-line treatment failed or H. pylori recurred, the unused MA or QUAD was used as a third-line treatment., Results: Eighty-six patients had recurrence at least once during consecutive lines of treatments. Among 2116 patients (intention-to-treat [ITT]) without recurrence, 1644 (77.7%, per-protocol [PP]) completely followed our treatment flow. The ITT and PP rates of first-line treatment were 69.8% and 89.3%. After second line, they reached 78.4% (ITT) and 98.4% (PP). The "final" eradication rate up to third line treatment were 80.0% (1692/2116) and 99.8% (1641/1644), respectively. Resistance to clarithromycin showed significantly lower eradication rate (OR 0.358, P < 0.001) than those with susceptible strains in multivariate analysis. However in PP analysis, there was no significant difference in ultimate success rate regarding resistance pattern., Conclusion: Final success rate of PP was high, 99.8% in Korea in spite of high antibiotic resistance rates. However, high rate of refusal of further treatment and follow-up loss made ITT eradication rate low. Proper strategy to improve the treatment adherence is needed., (© 2014 Journal of Gastroenterology and Hepatology Foundation and Wiley Publishing Asia Pty Ltd.)

Background and Aim: Gastric cancer is believed to develop by a multistage process. Intestinal metaplasia (IM) is regarded as a premalignant condition; it is classified into subtypes I, II and III. The aim of this study was to evaluate whether the subtypes of IM were associated with progression to gastric cancer., Methods: The study cohort consisted of 861 subjects, categorized as controls, gastric ulcers, dysplasia and cancer. The IM was scored histologically using the Sydney classification for the antrum and the body of the stomach. The biopsies were stained with high iron diamine and alcian blue (pH 2.5) (HID-AB2.5), and the IM was subtyped as I, II or III., Results: The proportion of IM subtypes I, II and III were 14.5%, 47.2% and 38.3% in the antrum, and 28.1%, 57.8% and 14.1% in the body of the stomach, respectively. These distributions did not show significant differences depending on disease or Helicobacter pylori positivity. In cases that were H. pylori-positive, the prevalence of IM subtype II in the cancer and dysplasia groups was higher than in the control group in the body of the stomach (P < 0.05). The proportion of IM subtype III in the antrum increased in proportion with age (P = 0.036)., Conclusions: IM subtyping was not found to play a major role in the prediction of gastric cancer development in Korea. IM subtype III was associated with aging, and IM subtype II appeared to be related to gastric carcinogenesis in the presence of H. pylori infection.

Although the Kidney Disease Quality of Life instrument (KDQOL-SF), which was designed to measure the comprehensive quality of life in patients with end stage renal disease, has been tested and widely administered in many other counties, it has not yet been translated, validated and reported for Korea. The primary purpose of this study was to validate a Korean version of KDQOL-SF and to evaluate its psychometric properties. The study subjects were 164 patients with hemodialysis or continuous ambulatory peritoneal dialysis in university dialysis centers in Korea. In order to investigate the reliability, test-retest reliability and internal consistency reliability were assessed. Both test-retest reliability and internal consistency reliability were found to be high. In order to investigate the construct validation, all the items of the SF-36 scales, an established generic QOL measures, were compared with an overall health rating scale in kidney disease-targeted scale. They found to be highly correlated with each other. Moreover, overall health rating scale was significantly correlated with symptoms/problems, effects of kidney disease, burden of kidney disease, cognitive function (p < 0.001), and quality of social interaction (p < 0.05). These results suggest that the Korean version of KDQOL-SF satisfies its reliability and validity in Korean patients with hemodialysis or continuous ambulatory peritoneal dialysis. This questionnaire provides important and clinically valuable information for understanding the health related quality of life in the Korean patients with dialysis.

Two strictly aerobic, Gram-negative bacteria, designated strains CL-SP27T and B5-6T, were isolated from the hypersaline water of a solar saltern in Korea and from the surface water of the Sargasso Sea, respectively. The two strains were rod-shaped, non-motile and grew on marine agar 2216 as beige colonies. Phylogenetic analyses of 16S rRNA gene sequences revealed a clear affiliation of the novel strains to the family Rhodobacteraceae. However, the novel strains were only distantly related to members of the Roseobacter clade, forming a distinct lineage. Although the 16S rRNA gene sequence similarity between strains CL-SP27T and B5-6T was very high (99.6 %), DNA-DNA relatedness between the strains was 48.4 %, suggesting that the strains be categorized as two genospecies. Additionally, the two novel strains could be differentiated by DNA G+C contents, fatty acid profiles, carbon source utilization patterns, antibiotic susceptibilities and biochemical characteristics. Based on taxonomic data obtained in this study, strains CL-SP27T and B5-6T represent separate species within a novel genus of the family Rhodobacteraceae, for which the names Maribius salinus gen. nov., sp. nov. (type species) and Maribius pelagius sp. nov. are proposed. The type strains of Maribius salinus and Maribius pelagius are CL-SP27T (=KCCM 42113T=JCM 13037T) and B5-6T (=KCCM 42336T=JCM 14009T), respectively.

A lemon-shaped marine bacterium, strain CL-SP20(T), isolated from hypersaline water from a solar saltern in Korea, was characterized in terms of its physiological and biochemical features, its fatty acid profile and its phylogenetic position based on 16S rRNA gene sequences. Analysis of the 16S rRNA gene sequence revealed a clear affiliation with the Roseobacter lineage (91.0-96.3 % similarity) of the family Rhodobacteraceae. However, strain CL-SP20(T) did not form a robust clade with any species of the Roseobacter clade, forming a distinct subline. Strain CL-SP20(T) is non-motile and forms beige colonies on marine agar. The strain is able to grow with sea salts at concentrations in the range 1-10 %, with optimal growth between 5 and 6 %. It grows at temperatures in the range 15-40 degrees C and at pH 6-10. The strain cannot oxidize thiosulfate. The fatty acids are dominated by 18 : 1omega7c (54.3 %) and 19 : 0 cyclo omega8c (20.4 %). The DNA G+C content is 67.3 mol%. According to the physiological data, fatty acid composition and phylogenetic analysis of the 16S rRNA gene sequence, strain CL-SP20(T) represents a novel species in a novel genus of the family Rhodobacteraceae, for which the name Citreimonas salinaria gen. nov., sp. nov. is proposed. The type strain of Citreimonas salinaria is CL-SP20(T) (=KCCM 42116(T)=JCM 13036(T)).

A rod-shaped marine bacterium, CL-TA03(T), isolated from a biofilm in a coastal fish farm in Tongyeong, Korea, was characterized for physiological and biochemical features, fatty acid profile and phylogenetic position based on 16S rRNA gene sequences. Analysis of the 16S rRNA gene sequence revealed a clear affiliation with the family Rhodobacteraceae. Phylogenetic analysis of the 16S rRNA gene sequence showed that the closest relatives of CL-TA03(T) were Thalassobius gelatinovorus and Thalassobius mediterraneus (95.6 % similarity). The sequence similarities between CL-TA03(T) and other type species of the Roseobacter lineage ranged from 92.4 to 95.4 %. Strain CL-TA03(T) is motile and grows on marine agar as colourless or beige colonies. The strain is able to grow optimally in the range of 3-5 % sea salts. It grows within a temperature range of 15-35 degrees C and at pH 6-10. The fatty acids are dominated by 18 : 1omega7c (64.1 %) and 11-methyl 18 : 1omega7c (10.6 %). The DNA G+C content is 57.2 mol%. According to physiological data, fatty acid composition and phylogenetic analysis of the 16S rRNA gene sequence, CL-TA03(T) is considered to represent a new genus in the family Rhodobacteraceae and the name Shimia marina gen. nov., sp. nov. is proposed. The type strain of Shimia marina is CL-TA03(T) (=KCCM 42117(T)=JCM 13038(T)).