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The solvent stabilizer 1,4-dioxane could have harmful effects on an ecosystem. The discharge limit of 1,4-dioxane in a body of water will be regulated at 5 mg/L in Republic of Korea. Thus, the currently operating activated sludge used in the manufacture of polyester should be properly treated to meet the regulations. Accordingly, the removal rate of 1,4-dioxane and its microbial properties was assessed at K, H and T corporations. The highest removal efficiencies were recorded at H. However, the concentration of 1,4-dioxane in the effluent of T exceeded the criterion. In addition, a microbial degradation test was conducted on 100 mg/L of 1,4-dioxane inoculated with the activated sludge from each of the three corporations. After 7 days, the 1,4-dioxane was completely removed with the H sludge and efficiencies were 67% in the T sludge and 52% in the K sludge. These results confirm that the biodegradability of 1,4-dioxane may vary in relation to the microbial properties. The microbial diversity of activated sludge of each company was therefore investigated by 16S rDNA cloning methods. In conclusion, the activated sludge of H is the most effective for the biodegradation of 1,4-dioxane. This fact is of significant concern for the industrial sector. [ABSTRACT FROM AUTHOR]

The cyclic ether 1,4-dioxane is a synthetic industrial chemical that is used as a solvent in producing paints and lacquers. The EPA and the International Agency for Research on Cancer(IARC) classified 1,4-dioxane as a GROUP B2(probable human) carcinogen. 1,4-dioxane is also produced as a by-product during the manufacture of polyester. In this research, a polyester manufacturing company (i.e. K Co.) in Gumi, Korea was investigated regarding the release of high concentrations of 1,4-dioxane (about 600 mg/L) and whether treatment prior to release should occur to meet with the level of the regulation standard (e.g., 5 mg/L in 2010). A 10 ton/day pilotscale treatment system using photo-Fenton oxidation was able to remove approximately 90% of 1,4-dioxane under the conditions that concentrations of 2800ppm H2O2 and 1,400ppm FeSO4 were maintained along with 10 UV-C lamps (240μW/cm2) installed and operated continuously during aeration. However, the effluent concentration of 1,4-dioxane was still high at about 60 mg/L where TOC concentration in the effluent had been moreover increased due to decomposed products such as aldehydes and organic acids. Thus, further investigation is needed to see whether the bench scale (reactor volume, 8.9 L) of activated sludge could facilitate the decomposition of 1,4-dioxane and their by-products (i.e., TOC). As a result, 1,4-dioxane in the effluent has been decreased as low as 0.5 mg/L. The optimal conditions for the activated sludge process that were obtained are as follows: DO, 3-3.5 mg/L; HRT, 24 h; SRT 15 d; MLSS, 3,000 mg/L. Consequently, photo-Fenton oxidation coupled with activated sludge can make it possible to efficiently decompose 1,4-dioxane to keep up with that of the regulation standard. [ABSTRACT FROM AUTHOR]

As part of a marine habitat enhancement project, the physical and chemical deterioration of reinforced concrete reefs that were fully immersed in Tongyeong waters of Korea was investigated. For the investigation, marine environmental factors such as seawater, salinity, pH, dissolved oxygen, sea-bottom materials, and water depth of the targeted sites were surveyed from 1997 to 2001. Then, four reinforced concrete reefs from four different sites were recovered and tested by using various destructive and nondestructive methods. Based on the observations and test results, it was seen that the reinforced concrete reefs have sound physical and chemical properties, except for chloride concentration and its associated factors. However, because of the lack of dissolved oxygen in the targeted seawaters and its continuous supply, it is concluded that the originally designed service life will be achieved, and in fact the concrete reefs will have an even longer service life than expected. By considering an extreme event such as impact loading under installation and construction, a new minimum concrete cover depth of 40 mm is introduced into practice. [ABSTRACT FROM AUTHOR]

Colorectal cancer has been reported to be the malignancy most frequently associated with gastric cancer in Korea. The aim of this study was to define the frequency and clinical characteristics of synchronous gastric cancer detected at preoperative esophagogastroduodenoscopy (EGD) in colorectal cancer patients. This prospective study analyzed the EGD results from 1,542 consecutive colorectal cancer patients who underwent surgery from January 2003 to December 2005 at the Center for Colorectal Cancer, National Cancer Center, Korea. Of the 1,542 cases, 1,155 (74.9%) underwent EGD at our center and 387 underwent EGD at other hospitals within 6 months before surgery. Of the 1,542 cases, synchronous gastric cancers were detected in 31 cases (2.0%). Of these 31 cases, 26 had early gastric cancer (EGC; 83.9%) and 5 had advanced gastric cancer. Ten (38.5%) of the 26 EGC cases were managed using endoscopic mucosal resection. Compared to colorectal cancer patients without synchronous gastric cancer, the group of patients with synchronous gastric cancer was older (65.5 ± 9.6 vs 58.4 ± 11.3 years, p = 0.001) and had a greater proportion of males (77.4 vs 59.4%, p = 0.043). This study found that 2% of Korean sporadic colorectal cancer patients had synchronous gastric cancer. A preoperative EGD for colorectal cancer patients is likely to greatly assist in the diagnosis of synchronous gastric cancer at an early stage and the implementation of appropriate minimally invasive treatment. [ABSTRACT FROM AUTHOR]

Background and Study Aims: Oral sodium phosphate (NaP) solution is widely used for colonoscopy bowel preparation and it may cause aphthous ulcers in the colon. Our aim was to evaluate whether oral NaP solution is associated with gastric mucosal lesions., Methods: A total of 20 070 individuals underwent esophagogastroduodenoscopy (EGD) with colonoscopy, and 4271 individuals underwent EGD without colonoscopy, for cancer screening. Oral NaP solutions were used for bowel preparation prior to colonoscopy. Hemorrhagic gastropathy was graded using a five-point scale for erosive mucosal injury. The effect of NaP bowel preparation on hemorrhagic gastropathy was estimated using multiple logistic regression analysis with odds ratios (ORs) and 95 % confidence intervals (CIs)., Results: The incidence of hemorrhagic gastropathy was 1.6 % (70/4271) in the EGD only group and 4.0 % (809/20 070) in the EGD with colonoscopy group ( P < 0.001, unadjusted OR 2.55, 95 %CI 1.99 - 3.27). The ORs for mild (grade 1 - 2), moderate (grade 3), and severe (grade 4) hemorrhagic gastropathy according to NaP use were 1.92 (95 %CI 1.45 - 2.54), 4.72 (95 %CI 2.65 - 8.47), and 5.99 (95 %CI 1.46 - 24.63), respectively. After adjustment for confounding factors, NaP solution was a significant risk factor for acute hemorrhagic gastropathy in the multivariate analysis (OR 1.92, 95 %CI 1.34-2.74). In addition, male sex, a body mass index (kg/m (2)) of less than 20, concurrent use of antihypertensive or nonsteroidal anti-inflammatory drugs, and duodenal ulcers were independently associated with the development of hemorrhagic gastropathy. HELICOBACTER PYLORI infection and atrophic gastritis were negatively associated with hemorrhagic gastropathy., Conclusion: Oral NaP bowel preparation for colonoscopy was associated with hemorrhagic gastropathy., ((c) Georg Thieme Verlag KG Stuttgart . New York.)

Background: Although obesity and weight gain increase the risk for symptoms of gastro-oesophageal reflux disease, their association with erosive oesophagitis is still unclear in the male population., Aim: To evaluate, in men, the association of body mass index (BMI) and weight gain with endoscopically proven erosive oesophagitis., Methods: A total of 8571 Korean men in a comprehensive screening cohort were enrolled. Effects of BMI and abdominal obesity on erosive oesophagitis were estimated with odds ratios (ORs) and 95% confidence intervals (CIs) using logistic regression analysis. We also evaluated the association between erosive oesophagitis and BMI change after 1-3 years., Results: The prevalence of erosive oesophagitis was 6.4% (552/8571). In univariate analysis, the ORs for erosive oesophagitis increased as BMI or waist circumference increased (P for trend <0.001, both). In multivariate analysis, OR for erosive oesophagitis increased as BMI increased (P for trend = 0.002), while the significance of waist circumference was attenuated (P for trend = 0.13). Increase in BMI (>or=1 kg/m2) was associated with persistence of erosive oesophagitis (OR = 2.83, 95% CI: 1.01-7.92, P = 0.04) and new development of the disease (OR = 2.13, 95% CI: 1.38-3.28, P = 0.001) compared with BMI change less than 1 kg/m2., Conclusions: Elevated BMI and weight gain have a significant association with erosive oesophagitis.

Objective: Recently we have proposed a modified set of criteria to settle the questions raised regarding the International Study Group (ISG) criteria for Behçet's disease (BD). The aim of the present study was to validate the two pre-existing criteria sets commonly used in Korea, the ISG criteria and the criteria of the Behçet's Disease Research Committee of Japan (Japanese criteria), as well as the proposed modified criteria., Methods: The study population included 155 consecutive patients with BD and 170 controls with non-Behçet's rheumatic diseases. Detailed data for all of the subjects were recorded prospectively by the participating physicians on a standard form that listed the clinical features of BD. The sensitivity, specificity, and accuracy of each set of the criteria were measured., Results: Of the three criteria sets employed, the modified criteria were the most accurate, with an accuracy of 96.3%. The ISG criteria often failed to classify the following patients with BD: patients with only oral and genital ulcerations, certain patients with intestinal ulcerations, patients who did not manifest oral ulcerations, and patients with acute disease but fewer than three recurrent oral ulceration relapses in a 1-year period. The Japanese criteria also failed to categorize the following patients with BD: patients with oral and genital ulcerations, and patients with oral ulcerations, skin lesions, and a positive pathergy reaction. In addition, the Japanese criteria misclassified some of the control subjects with non-Behçet's uveitis as having BD., Conclusions: The results of this study suggest that there are some points that need to be reconsidered in the clinical application of the two pre-existing sets of criteria. Although the modified criteria were the most accurate, further validation studies will be required in other ethnic populations.

Objective: To determine whether HLA-DR alleles are associated with the development and clinical features of Adult Onset Still's Disease (AOSD) in Korea., Methods: Forty-seven patients (41 women, 6 men, mean age at diagnosis 31.6 yr) meeting Yamaguchi's criteria for AOSD and 144 healthy controls were enrolled in this study. The patients with AOSD were subdivided into groups according to their chronicity: monocyclic systemic, polycyclic systemic, and chronic destructive type, and were furthermore classified as non-articular, oligoarticular or polyarticular types (having arthritis involving 5 or more joints) according to the extent of articular involvement. HLA-DRB1 genotypes were assessed by PCR-SSOP., Results: Patients with AOSD had more frequent DRB1*12 (p = 0.028, relative risk (RR) = 2.27, 95% confidence interval (CI): 1.08-4.80) and DRB1*15 (p = 0.013, RR = 2.16, 95% CI: 1.17-4.00). They had less frequent DRB1*04 (p = 0.006, RR = 0.35, 95% CI: 0.16-0.75) compared to controls. DRB1*14 (p = 0.011, RR = 3.80, 95% CI: 1.27-11.31) were associated with the monocyclic systemic type., Conclusion: Korean AOSD patients had more frequent DRB1*12 and DRB1*15, and less frequent HLA-DRB1*04. The patients with the monocyclic systemic type had more frequent DRB1*14 alleles. This study suggests that Korean AOSD patients have distinct immunogenetic profiles, and that it would be valuable to assess the relationships between HLA-DRB1 genes and polymorphisms of proinflammatory cytokines in the pathogenesis of AOSD.

The Study was carried out for the purpose of investigating the degree of perception in nursing activities. This study reports perceptions of nurses on the choices they make among competing activities, contrasts this perception with their opinion of what tasks they would like to spend time on. A sample of 231 clinical nurses was selected to participate in this study at two general hospitals in Seoul. The data was collected from July 10th to 25th, 1990. Subjects were instructed to rate one of five points likert type scale on the 43 items of nursing activities. Analysis of data was done by means of the SPSS-X Program using frequency, t-test and ANOVA. The results of this study were as follows; 1. The characteristics of the subjects were as follows: The age group of 25-29 years was 45.9%. For religion, Christians had the highest score, 68.4% and singles in subjects were 81.4%. For academic background, 64.5% were graduated from nursing junior colleges. In the subjects, staff nurses were 86.6%. 22.5% of them had worked for less than 1 year and 20.8% had 37 months to 5 years experience at the time of the survey. 62.8% were satisfied with the job. 2. The perception level of nursing activities: 1) The mean score for perception of professional nursing functions was 4.157 point, with a maximum score set at 5 points. The mean score for perception of priorities was 3.781. Perception of spending time was 3.932. 2) In perception of professional nursing functions, more important items were Aseptic technique (4.866), Shift and exchange of information concerning patients(4.654), Observing patients (4.799). Less important items were Transporting patients(3.411), Changing linens(3.442), Giving a bed shampoo (3.506). In priorities, more important ones were Aseptic technique(4.706), Shift and exchange of information concerning patients(4.524), Observing patients(4.390), Taking vital signs(4.355). And less important ones were Changing linens (3.100), Giving bed baths(3.113), Giving back rubs(3.121). In spending time, more important ones were Aseptic technique(4.706), Observing patients (4.532), Shift and exchange of information concerning patients(4.532). And less important ones were Changing lines(3.368), Transporting patients(3.394), Giving bed baths(3.450). 3) In the role perception level, the mean distribution of perception was 3.511-4.335; the role was perceived to be in order of frequency as a facilitator, coordinator, change agent and advocator role. The most important scale of factors by nursing activities was indirect nursing activities.