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Climatic fluctuations and geological events since the LGM are believed to have significantly impacted the population size, distribution, and mobility of many species that we observe today. In this paper, we determined the processes driving the phylogeographic structure of the Korean endemic white forsythia by combining the use of genome‐wide SNPs and predicting paleoclimatic habitats during the LGM (21 kya), Early Holocene (10 kya), Mid‐Holocene (6 kya), and Late Holocene (3 kya). Using a maximum of 1897 SNPs retrieved from 124 samples across nine wild populations, five environmental predictors, and the species' natural occurrence records, we aimed to infer the species' demographic history and reconstruct its possible paleodistributions with the use of approximate Bayesian computation and ecological niche models, respectively. Under this integrated framework, we found strong evidence for patterns of range shift and expansion, and population divergence events from the onset of the Holocene, resulting in the formation of its five distinct genetic units. The most highly supported model inferred that after the split of an ancestral population into the southern group and a larger central metapopulation lineage, the latter gave rise to the eastern and northern clusters, before finally dividing into two sub‐central groups. While the use of molecular data allowed us to identify and refine the (phylo)genetic relationships of the species' lineages and populations, the use of ecological data helped us infer a past LGM refugium and the directions of post‐glacial range dynamics. The time frames of these demographic events were shown to be congruent with climatic and geological events that affected the central Korean Peninsula during these periods. These findings gave us a better understanding of the consequences of past spatiotemporal factors that may have resulted in the current fragmented population distribution of this endangered plant. [ABSTRACT FROM AUTHOR]

This study reconstructs total electron content (TEC) maps in the vicinity of the Korean Peninsula by employing a deep convolutional generative adversarial network and Poisson blending (DCGAN‐PB). Our interest is to rebuild small‐scale ionosphere structures on the TEC map in a local region where pronounced ionospheric structures, such as the equatorial ionization anomaly, are absent. The reconstructed regional TEC maps have a domain of 120°–135.5°E longitude and 25.5°–41°N latitude with 0.5° resolution. To achieve this, we first train a DCGAN model by using the International Reference Ionosphere‐based TEC maps from 2002 to 2019 (except for 2010 and 2014) as a training data set. Next, the trained DCGAN model generates synthetic complete TEC maps from observation‐based incomplete TEC maps. Final TEC maps are produced by blending of synthetic TEC maps with observed TEC data by PB. The performance of the DCGAN‐PB model is evaluated by testing the regeneration of the masked TEC observations in 2010 (solar minimum) and 2014 (solar maximum). Our results show that a good correlation between the masked and model‐generated TEC values is maintained even with a large percentage (∼80%) of masking. The performance of the DCGAN‐PB model is not sensitive to local time, solar activity, and magnetic activity. Thus, the DCGAN‐PB model can reconstruct fine ionospheric structures in regions where observations are sparse and distinguishing ionospheric structures are absent. This model can contribute to near real‐time monitoring of the ionosphere by immediately providing complete TEC maps. Plain Language Summary: Total electron content (TEC) is a parameter that represents the column number density of ionospheric plasma. This parameter is a valuable resource for the study of ionospheric phenomena and the prediction of space weather caused by the ionosphere. The dense ground‐based network of Global Navigation Satellite System (GNSS) stations provides the means to generate global TEC maps which are essential for the continuous monitoring of the ionosphere. However, data are always missing, especially in the ocean area, due to the geographical limitations of ground‐based GNSS stations. Recently, several studies applied deep learning techniques to overcome the shortcomings in the construction of global TEC maps. However, deep learning techniques have not yet been tested for the reconstruction of high‐resolution regional TEC maps. By applying the deep learning techniques developed in previous studies, we successfully reconstructed regional TEC maps in the vicinity of the Korean Peninsula. Our results demonstrate that deep learning techniques can contribute to near real‐time monitoring of the ionosphere by immediately providing complete, high‐resolution TEC maps. Key Points: Local total electron content maps are completed with deep convolutional generative adversarial network and Poisson blending (DCGAN‐PB)The DCGAN‐PB model satisfactorily fills data gaps and reconstructs fine ionospheric structures in the vicinity of the Korean PeninsulaThe DCGAN‐PB model performance is not sensitive to observed data number and geophysical parameters [ABSTRACT FROM AUTHOR]

This study compared the characteristics and mortality of new implantation of cardiac implantable electronic device (CIED) between tertiary and non-tertiary hospitals. From national health insurance claims data in Korea, 17,655 patients, who underwent first and new implantation of CIED between 2013 and 2017, were enrolled. Patients were categorized into the tertiary hospital group (n = 11,560) and non-tertiary hospital group (n = 6095). Clinical outcomes including in-hospital death and all-cause death were compared between the two groups using propensity-score matched analysis. Patients in non-tertiary hospitals were older and had more comorbidities than those in tertiary hospitals. The study population had a mean follow-up of 2.1 ± 1.2 years. In the propensity-score matched permanent pacemaker group (n = 5076 pairs), the incidence of in-hospital death (odds ratio [OR]: 0.76, 95% confidence interval [CI]: 0.43–1.32, p = 0.33) and all-cause death (hazard ratio [HR]: 0.92, 95% CI 0.81–1.05, p = 0.24) were not significantly different between tertiary and non-tertiary hospitals. These findings were consistently observed in the propensity-score matched implantable cardioverter-defibrillator group (n = 992 pairs, OR for in-hospital death: 1.76, 95% CI 0.51–6.02, p = 0.37; HR for all-cause death: 0.95, 95% CI 0.72–1.24, p = 0.70). In patients undergoing first and new implantation of CIED in Korea, mortality was not different between tertiary and non-tertiary hospitals. [ABSTRACT FROM AUTHOR]

Herein, we aim to assess mortality risk prediction in peritoneal dialysis patients using machine-learning algorithms for proper prognosis prediction. A total of 1,730 peritoneal dialysis patients in the CRC for ESRD prospective cohort from 2008 to 2014 were enrolled in this study. Classification algorithms were used for prediction of N-year mortality including neural network. The survival hazard ratio was presented by machine-learning algorithms using survival statistics and was compared to conventional algorithms. A survival-tree algorithm presented the most accurate prediction model and outperformed a conventional method such as Cox regression (concordance index 0.769 vs 0.745). Among various survival decision-tree models, the modified Charlson Comorbidity index (mCCI) was selected as the best predictor of mortality. If peritoneal dialysis patients with high mCCI (>4) were aged ≥70.5 years old, the survival hazard ratio was predicted as 4.61 compared to the overall study population. Among the various algorithm using longitudinal data, the AUC value of logistic regression was augmented at 0.804. In addition, the deep neural network significantly improved performance to 0.841. We propose machine learning-based final model, mCCI and age were interrelated as notable risk factors for mortality in Korean peritoneal dialysis patients. [ABSTRACT FROM AUTHOR]

Abstract: Aim: This study aimed to explore the trends in individual income and to estimate the change in average monthly income for patients undergoing haemodialysis therapy. Methods: The main data source was the Clinical Research Center (CRC) for End‐Stage Renal Disease in Korea. In addition to the cohort data, a survey was conducted to capture personal income for 3 years. To estimate the change in monthly income over time using repeated measures, a random coefficient model using penalized quasi‐likelihood methods based on restricted or residual maximum likelihood estimation was used. Results: During the 3‐year study period, 138 subjects aged 20 and over who answered the question about pre‐dialysis income were traced and analyzed. The median value of monthly income was $US564.4 in the 1st year, $470.4 in the 2nd year, and $733.8 in the 3rd year, representing a 70%, 75%, and 61% decrease compared to pre‐dialysis income ($1881.5), respectively. By using mixed analysis, we found that monthly income change was $1283 (95% CI, −1621.5, −945.1), $1182 USD (95% CI, −1540.8, −823.1), and $1041 (95% CI, −1457.6, −623.6) in the 1st, 2nd, and 3rd year, respectively, compared to pre‐dialysis income after controlling for other covariates. Women and less educated patients had a relatively higher reduction of income, despite the low starting point. Conclusions: The monthly income of dialysis patients reduced substantially over the study period, especially at the time of the first survey. Considering the social security system, haemodialysis patients face significant personal financial burdens due to their ESRD unrelated to the direct costs of dialysis treatment. [ABSTRACT FROM AUTHOR]

The physiologic tooth position is determined by interactions between the periodontal tissue and occlusal, tongue, and lip forces. Bone destruction resulting from chronic periodontal disease disturbs the equilibrium of these interactive balances, leading to pathologic tooth migration, often requiring multidisciplinary treatment approaches. The present case demonstrates a systematic periodontal-orthodontic-prosthetic treatment for achieving the optimal structural, functional, and esthetic outcomes. [ABSTRACT FROM AUTHOR]

Highlights • Through a Bayesian modeling framework, various definitions of sources of uncertainty are explored. • Variance in future streamflow projections may be underestimated if climate model similarities are ignored. • The simple error model approach used in defining hydrologic error uncertainty may create incorrect information in the quantiles of streamflow projections. Abstract Quantifying uncertainty in projecting climate change impact on flood frequency analysis is particularly relevant for long-term water resources planning and management. This study examines uncertainties arising from (1) a climate model, with and without accounting of intermodel similarities, (2) a hydrological model with two different error model definitions, which have previously received less attention in studies propagating uncertainty through climate change impacts on flood response. Through a Bayesian modeling framework, a proposed statistical framework is utilized to explore various definitions of sources of uncertainty and to develop a series of nested formulations that can evaluate the leverage of specific uncertainty sources in quantiles of future streamflow. To be specific, climate model similarity, hydrologic prediction error, and frequency analysis are formally modeled with an appropriate likelihood function. The quantiles inferred by each formulation are compared in a case study of the Yongdam Basin in Korea. Results indicate that variance in hydrologic response is underestimated if climate model similarities are ignored, and in many cases, the inferred quantiles of streamflow projection are biased accordingly. Furthermore, a simple error model used in defining hydrologic uncertainty may create incorrect information in determining the quantiles in streamflow projection. The approach presented here of quantifying uncertainty has the potential to better depict overall multi-source uncertainties in projections of climate change impacts on hydrologic response. Finally, our results also indicate that careful flood planning management may be required for the Yongdam Basin in future summers. [ABSTRACT FROM AUTHOR]

Objectives: It is unclear whether high-intensity statin therapy provides incremental clinical benefits over moderate-intensity statin therapy in Asian patients with angina. This study sought to compare the clinical outcomes of moderate- and high-intensity statin therapies in patients undergoing percutaneous coronary intervention (PCI) for angina in Korean patients. Methods: Based on the national health insurance claims data in South Korea, patients aged 18 years or older without a known history of coronary artery disease, who underwent PCI with drug-eluting stents due to angina between 2011 and 2015, were enrolled. According to the intensity of statin therapy, patients were categorized into moderate-intensity statin therapy (n = 23,863) and high-intensity statin therapy (n = 9,073) groups. The primary endpoint, defined as a composite of all-cause death and myocardial infarction, was compared between the two groups using a propensity-score matching analysis. Results: During the follow-up period (median, 2.0 years; interquartile range, 1.1–3.1), 1,572 patients had 1,367 deaths and 242 myocardial infarctions. After propensity-score matching, there were 8,939 matched pairs. There was no significant difference in the incidence of the primary endpoint between the two groups (adjusted hazard ratio of high-intensity statin therapy, 1.093; 95% confidence interval: 0.950–1.259; p = 0.212). Conclusions: In Korean patients undergoing PCI with drug-eluting stents for angina, the high-intensity statin therapy did not provide additional clinical benefits over the moderate-intensity statin therapy. [ABSTRACT FROM AUTHOR]

ABSTRACT Kim, H.-C.; Song, Y.-S.; Kim, Y.H.; Son, S.; Cho, J.-G.; Chang, W.K.; Lee, C.-H.; Nam, J., and Ryu, J., 2018. Implications of esuarine and coastal management in the growth of Porphyra sp. in the Geum River Estuary, South Korea: A modeling study. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 396–400. Coconut Creek (Florida), ISSN 0749-0208. Laver (Porphyra sp.) is one of macroalgae species that has been cultivated for the purpose of food consumption in the coastal areas of Korean Peninsula. In specific, Porphyra tenera Kjellman and Porphyra yezonensis Ueda are two major commercial species for aquaculture in the west coast of Korea. In this study authors employed an ecosystem modeling approach (Hadley et al., 2014) to simulate the nutrient physiology and growth of the laver in aquaculture facilities located in the vicinities of Geum River Estuary. Some of model coefficients and parameterizations were modified from the original version based on laboratory experiments, if necessary. In addition, authors calibrated and validated the Delft3D (https://oss.deltares.nl/web/delft3d) with long-term time series data from the area. The Delft3D is an open source modeling suite that can simulate hydrodynamics (temperature, salinity, flow fields), sediment transport and water quality variables (inorganic nutrients). As one of the end-point goals of the present study is to develop decision supporting tools that can be used by coastal managers, the macroalgae growth model was coupled with the Delft3D in order to predict effects of episodic climatic events and/or upstream water management decisions on the estuarine ecosystem. Temperature, salinity and nitrogen loadings estimated from the Delft3D were used as input to the ecosystem model, and subsequent responses from Porphyra sp. were numerically simulated. Given thirteen scenario-based simulations, it is found that model simulated dissolved inorganic nitrogen concentrations do not change significantly for the same climatic condition. However, the maximum potential annual production of macroalgae is found to be more dependent on ammonium ion concentration. [ABSTRACT FROM AUTHOR]

Purpose: Diabetic nephropathy is the leading cause of end stage renal disease. The number of kidney transplantation (KT) due to diabetic nephropathy is increasing and there is debate on glycemic control after KT. In this study, we used a multi-center database to determine the relationship between post-transplant glycemic control and the outcomes of KT in patients with diabetic nephropathy. Methods: We conducted a retrospective chart review of kidney transplant recipients (KTRs) with diabetic nephropathy from three tertiary hospitals to analyze the association between post-transplant glycemic control and the clinical outcomes of graft failure, including patient death and biopsy-proven acute rejection (BPAR). We assessed time-averaged glucose level and hemoglobin A1c (HbA1c) for 36 months after KT. Results: Among 3,538 KTRs, a total of 476 patients received kidney transplantation because of diabetic nephropathy. Mean time-averaged glucose and HbA1c levels were 147 ± 46 mg/dl and 7.7 ± 1.5%, respectively. Patients with diabetic nephropathy had poor graft and patient survival rate compared with non-diabetic nephropathy. Among KTRs with diabetic nephropathy, the highest quartile of time-averaged glucose was related to poor graft outcomes and the 3rd quartile of time-averaged HbA1c was associated with significantly better graft outcomes than the 1st, 2nd or 4th quartiles. There were no significant differences in the risk of BPAR across the 4 quartiles of glucose and HbA1c. Conclusions: Strict glycemic control before KT might not be related to successful outcomes but poor glycemic control after KT is associated with poor graft outcomes. There was no significant relationship between pre- or post-transplant glycemic control and BPAR. [ABSTRACT FROM AUTHOR]

There are several methods available in measuring food taste. The sensory evaluation, for instance, is a typical method for panels to test of taste and recognize smell with their nose by measuring the degree of taste characteristic, intensity, and pleasure. There are many issues entailed in the traditional sensory evaluation method such as forming a panel and evaluation cost; moreover, it is only localized in particular areas. Accordingly, this paper aimed to select food in one particular area, and compare and review the content between sensory evaluations using a taste biological sensor, as well as presenting an analysis of brainwaves using EEG and finally a proposal of a new method for sensory evaluation. In this paper, the researchers have conducted a sensory evaluation whereas a maximum of nine points were accumulated by purchasing eight types of rice wine. These eight types of Makgeolli were generalized by generating multidimensional data with the use of TS-5000z, thus learning mapping points and scaling them. The contribution of this paper, therefore, is to overcome the disadvantages of the sensory evaluation with the usage of the suggested taste biological sensor system. [ABSTRACT FROM AUTHOR]

Background: The atherogenic index of plasma (AIP), which is the logarithmic ratio of triglyceride (TG) to high-density lipoprotein cholesterol (HDL-C), had a linear relationship with clinical outcomes in the general population. However, the association of each lipid profile, TG and HDL-C, with survival was not straightforward in dialysis patients. This non-linear association led us to further investigate the prognostic impact of the AIP in these patients. Methods: From a nationwide prospective cohort, 1,174 incident dialysis patients were included. Patients were categorized into quintiles according to the AIP. An independent association of the AIP with all-cause and cardiovascular mortality was determined. Results: During a mean follow-up duration of 33.2 months, 170 patients (14.5%) died, and cardiovascular death was observed in 55 patients (4.7%). Multivariate Cox analyses revealed that the lowest (quintile 1, hazard ratio [HR] = 1.76, 95% confidence interval [CI] = 1.02–3.03) and the highest (quintile 5, HR = 2.15, 95% CI = 1.26–3.65) AIP groups were significantly associated with higher all-cause mortality compared to patients in quintile 3 (reference group). In terms of cardiovascular mortality, only the highest AIP group (quintile 5, HR = 2.59, 95% CI = 1.06–6.34) was significantly associated with increased risk of mortality. Sensitivity analyses showed that a U-shaped association between the AIP and all-cause mortality remained significant in non-diabetic and underweight to normal body mass index patients. Conclusions: Both the highest and the lowest AIP groups were independently associated with all-cause mortality, showing a U-shaped association. It suggested further studies are needed to identify targets and subgroups that can benefit from intervention of the AIP in incident dialysis patients. [ABSTRACT FROM AUTHOR]

Objective The purpose of this study was to adapt the pain DETECT Questionnaire ( PD-Q) into a Korean version ( KPD-Q) and validate it. Methods A single-center prospective observational study was performed. During the first phase of the study, linguistic adaptation was carried out to develop the KPD-Q. During the second phase of the study, feasibility, internal consistency, discriminant validity, and concurrent validity were assessed for psychometric validation of the KPD-Q. Results A total of 232 patients participated. Among them, 82 patients (35%) were classified in the neuropathic pain (NeP) group, 80 (34%) in the nociceptive pain group, and 70 (30%) in the mixed pain group. Regarding the reliability of the KPD-Q, internal consistency for the whole scale was 0.804, as evaluated by Cronbach's alpha. Pearson's correlation between the Leeds Assessment of Neuropathic Symptoms and Signs scale and the KPD-Q scores was positive and statistically significant ( r = 0.74, P < 0.001). Similar to the result obtained by the original developers, a value of ≥ 19 points suggested a clear diagnosis of the presence of an NeP component with 95.4% sensitivity, 73.8% specificity, and 0.737 Youden index. We used ≤ 13 (as opposed to ≤ 12, as suggested previously) as an alternative cutoff value, which showed a sensitivity of 95.4%, specificity of 73.8%, and the Youden index of 0.691. Conclusion The KPD-Q showed good psychometric and discriminant features for assessing the neuropathic component in chronic pain patients. We hope that this newly validated KPD-Q will be recognized in Korea as a credible tool for detection of NeP and thus may be used in further international clinical research. [ABSTRACT FROM AUTHOR]

We evaluated major cytogenetic abnormalities associated with childhood acute lymphoblastic leukemia (ALL) through both fluorescent in situ hybridization and conventional chromosomal analysis for 132 ALL patients diagnosed at St Mary's Hospital in Korea. Chromosome abnormalities have been detected in 92% of patients. Eighteen (14%) patients showed numerical abnormalities only, 50 (38%) patients showed structural abnormalities only, and 53 (40%) patients showed both. The simultaneous trisomies 4, 10 and 17 were observed in 23 (17%) patients. Of the patients with abnormal karyotypes, recurrent structural abnormalities were determined in 103 (78%) cases. t(12;21)(q13;q22) was found in 29 (22%) out of 132 patients, 9p abnormalities in 13 (10%) patients, t(1;19)(q23;p13.3) in 11 (8%) patients, t(9;22)(q34;q11.2) in 11 (8%) patients, and 11q23 abnormalities in 7 (5%) patients. Interestingly, we identified five uncommon translocations such as t(5;12) (q33;p13), t(14;19)(q32;q13.1), t(12;16)(p13;q13), der(1)t(1;12)(p32;p13), and t(5;15)(p15;q11.2). Our study pool is representative of pediatric ALL patients in Korea as it consists of about 20% of patients diagnosed annually in Korea. We believe that the data provided will aid in comparative studies of the treatment outcomes, as well as the type and incidence of chromosomal abnormalities associated with childhood ALL in various Asian nations and Western countries. [ABSTRACT FROM AUTHOR]

Background: Pre-transplant cardiovascular (CV) risk factors affect the development of CV events even after successful kidney transplantation (KT). However, the impact of pre-transplant CV risk factors on allograft failure (GF) has not been reported. Methods and Findings: We analyzed the graft outcomes of 2,902 KT recipients who were enrolled in a multi-center cohort from 1997 to 2012. We calculated the pre-transplant CV risk scores based on the Framingham risk model using age, gender, total cholesterol level, smoking status, and history of hypertension. Vascular disease (a composite of ischemic heart disease, peripheral vascular disease, and cerebrovascular disease) was noted in 6.5% of the patients. During the median follow-up of 6.4 years, 286 (9.9%) patients had developed GF. In the multivariable-adjusted Cox proportional hazard model, pre-transplant vascular disease was associated with an increased risk of GF (HR 2.51; 95% CI 1.66–3.80). The HR for GF (comparing the highest with the lowest tertile regarding the pre-transplant CV risk scores) was 1.65 (95% CI 1.22–2.23). In the competing risk model, both pre-transplant vascular disease and CV risk score were independent risk factors for GF. Moreover, the addition of the CV risk score, the pre-transplant vascular disease, or both had a better predictability for GF compared to the traditional GF risk factors. Conclusions: In conclusion, both vascular disease and pre-transplant CV risk score were independently associated with GF in this multi-center study. Pre-transplant CV risk assessments could be useful in predicting GF in KT recipients. [ABSTRACT FROM AUTHOR]

Background The purpose of this study was to determine if hyperinsulinemia and/or insulin resistance are/is associated with the prevalence of papillary thyroid cancer (PTC) in Korean women. Methods This study included 735 female patients with PTC and 537 female non-PTC control subjects. Multiple logistic regression analysis was performed to evaluate the associations between hyperinsulinemia/insulin resistance and the occurrence of PTC. Results The prevalence of PTC was significantly correlated with increased insulin, glucose levels, and a high homeostasis model of assessment-insulin resistance (HOMA-IR). The multivariate adjusted odds ratios for the prevalence of PTC in the highest quartile groups for insulin, glucose, and HOMA-IR were 2.88, 9.32, and 4.07 (all p < .001), respectively, compared with the lowest quartile groups. Pathological analyses revealed that increased serum glucose, insulin levels, and a higher HOMA-IR were associated with the multifocality of PTC. Conclusion Hyperinsulinemia and/or insulin resistance may be associated with the development of PTC, but not disease severity in Korean women. [ABSTRACT FROM AUTHOR]

In this paper, the PTO severeness of an agricultural tractor during rotary tillage and baler operation was analyzed. The S–N curves of the PTO driving gears were obtained through fatigue life test. To obtain the S–N curves of the PTO driving gears, the breakage time and rotational speed of the gears were measured through observation of the bending stress with changing torque. The torque acting on the PTO was measured and analyzed during rotary tillage and baler operation. Rotary tillage and baler operation were conducted at two ground speeds and two PTO rotational speeds at upland field sites with similar soil conditions, respectively. The load data were inverted to a load spectrum using rain-flow counting and SWT equations. Modified Miner’s rule was used to calculate the partial damage sum. The severeness was defined as the relative ratio of the damage sum. The results showed that the damage of the PTO increased when the ground speed or the PTO rotational speed increased. The effect of the PTO rotational speed on the severeness of the PTO was more significant than that of the ground speed. The severeness of the PTO of rotary tillage was greater than that of baler operation. [ABSTRACT FROM AUTHOR]

This study aims to analyze utilization of science and technology statistics through the science and technology statistics system which collects and provides science and technology statistics information in a systematic manner and propose a plan to strengthen the use of services. For this, it attempted to survey the current development of science and technology statistics system and trend of science and technology statistics, present analysis results and suggest a plan to strengthen the use of service. [ABSTRACT FROM AUTHOR]

Background: Health-related quality of life (HRQOL) has recently become an important issue. It reportedly affects morbidity and mortality in patients with end-stage renal disease (ESRD). In this study, we investigated whether early referral and planned dialysis improve the HRQOL and depression of patients with ESRD. Methods: We prospectively enrolled newly diagnosed patients with ESRD, from 31 hospitals in Korea, who completed questionnaires at 3 months after dialysis. We also got follow-up survey at 1 year after dialysis. To measure HRQOL and depression, Kidney Disease Quality of Life Short Form 36 (KDQOL-36) and Beck’s Depression Inventory (BDI) were utilized. Results: A total of 643 patients were analyzed. Referral type did not affect either KDQOL-36 or BDI scores. However, the planned dialysis group showed significantly better scores in 4 of 5 KDQOL-36 domains than did the unplanned group at 3 months after dialysis and partly, the effect was sustained for 1 year after dialysis. The benefit of planned dialysis was significant after adjusting for age, sex, type of dialysis, marital status, educational attainment, occupation, modified Charlson comorbidity index, albumin, and hemoglobin levels. BDI scores were also lower which indicate less depressive mood in planned dialysis group than those in unplanned group both at 3 months and 1 year after dialysis. Conclusions: Not early referral but planned dialysis improved both the short- and long-term HRQOL and depression of patients with ESRD. Nephrologists should try to help patients to initiate dialysis in a planned manner. [ABSTRACT FROM AUTHOR]

The Korean traditional seafood jeotgal is consumed directly or as an additive in other foods to improve flavor or fermentation efficiency. Saeujot, made from salted and fermented tiny shrimp (SFS; Acetes japonicus), is the best-selling jeotgal in Korea. In this study, we reveal the microbial diversity and dynamics in naturally fermented shrimp by denaturing gradient gel electrophoresis (DGGE). The population fingerprints of the predominant microbiota and its succession were generated by DGGE analysis of universal V3 16S rDNA polymerase chain reaction (PCR) amplicons. Overall, 17 strains were identified from sequencing of 30 DGGE bands. The DGGE profiles showed diverse bacterial populations in the sample, throughout the fermentation of SFS. Staphylococcus equorum, Halanaerobium saccharolyticum, Salimicrobium luteum, and Halomonas jeotgali were the dominant bacteria, and their levels steadily increased during the fermentation process. Certain other bacteria, such as Psychrobacter jeotgali and Halomonas alimentaria appeared during the early-fermentation process, while Alkalibacterium putridalgicola, Tetragenococcus muriaticus, and Salinicoccus jeotgali appeared during the late-fermentation process. The members of the order Bacillales were found to be predominant during the fermentation of SFS. Furthermore, S. equorum was identified as the dominant bacterial isolate by the traditional method of culturing under aerobic and facultative anaerobic conditions. We expect that this information will facilitate the design of autochthonous starter cultures for the production of SFS with desired characteristic sensory profiles and shorter ripening times. [ABSTRACT FROM AUTHOR]

Red ginseng (RG) is the top-selling functional food in Korea, but is not recommended for use in hypertensive patients. This study was performed to determine the pharmacokinetic (PK) interaction between RG and amlodipine, an antihypertensive drug. RG (0, 0.5, 1, or 2 g/kg/d) was administered orally for 2 wk, and then amlodipine (10 mg/kg) was given orally, to Sprague-Dawley (SD) rats. Blood was collected at 0.08, 0.25, 1, 1.5, 2, 3, 6, 12, and 24 h after amlodipine administration. In intravenous (iv) study, RG (0, 1, or 2 g/kg/d) was administered orally to SD rats for 2 wk, followed by amlodipine (2 mg/kg) intravenously (iv). Plasma concentrations of amlodipine were analyzed using a high-pressure liquid chromatography–tandem mass system (LC-MS/MS). Oral administration of amlodipine produced an increase of time to maximum plasma concentration (tmax:2.6, 4.1, 8.3, and 8.9 h at 0, 0.5, 1, and 2 g/kg/d, respectively), and a decrease of maximum plasma concentration (Cmax:278.5, 212.4, 232.1, and 238.7 ng/ml at 0, 0.5, 1, and 2 g/kg/d, respectively.). However, the area under the concentration–time curve from time 0 to 24 h measurable concentration (AUC0-24 hwas 3487.4, 2895.4, 3158.2, and 3495 ng/h/ml at 0, 0.5, 1, and 2 g/kg/d respectively) was not significantly changed among the different dose groups. Administration of amlodipine iv produced no significant changes in the apparent terminal half-life, volume of distribution, and AUC0-24 hramong the different dose groups. These results suggest that RG induced negligible influence on amlodipine pharmacokinetically in rats. [ABSTRACT FROM PUBLISHER]

Objective: Despite the close relationship between the functional polymorphism C(-1019)G (rs6295) of the serotonergic 1A receptor (5-HT1A) and mood, few studies have investigated the relationship between rs6295 and bipolar disorder. Aims: In this study, we aimed to investigate whether rs6295 is associated with clinical prognosis and treatment response in patients with bipolar I disorder acute manic episodes. Methods: One hundred twenty-eight patients with bipolar I disorder and one hundred sixty-eight healthy controls were recruited. Associations between patients with bipolar I disorder and healthy controls were compared. In addition, age at onset, number of admissions, and treatment response, including response rate, mean changes in manic symptoms, number of anti-manic agents and the total dosage of mood stabilizers for acute manic symptoms were compared between the rs6295 GG and CG+ CC groups in patients with bipolar I disorder. We conducted a separate subgroup analysis according to gender. Results: There were no differences in frequency between patients and controls. In patients with bipolar disorder, clinical prognosis and treatment response were no different between GG and CG+ CC groups. However, in a subgroup analysis according to gender, male, but not female, patients in the GG group had a longer duration of illness and a greater number of both previous episodes and psychiatric ward admissions than did the GC+ CC group. Conclusions: Further studies should investigate the relationship between 5-HT1A polymorphisms and bipolar disorder in terms of mood episode and gender. [ABSTRACT FROM AUTHOR]

To investigate whether duration of diabetes has an impact on the effectiveness of insulinization in diabetes management. This open-label, noninterventional, observational registry was conducted at >500 centers in Korea. Patients with diabetes, on oral antidiabetic drugs, with HbA1c ≥7 % (53 mmol/mol) in the preceding 3 months, being considered for initiation of basal insulin by their physicians, were included. Data were collected at baseline and at 3 and 6 months. Of 6,616 patients evaluated, 62.5 % had diabetes for <10 years, while only 6.5 % patients had diabetes for ≥20 years. At the end of study, average HbA1c in patients with diabetes for <10 years, for 10 to <20 years, and for ≥20 years was 7.3 ± 1.0 % (56 ± 10.9 mmol/mol), 7.4 ± 1.0 % (57 ± 10.9 mmol/mol), and 7.6 ± 1.1 % (60 ± 12.0 mmol/mol), respectively. Over half the patients (50.7 %) with diabetes <10 years achieved HbA1c <7 % (53 mmol/mol) by the end of study, while only 42.1 and 35.1 % patients with diabetes for 10 to <20 and ≥20 years, respectively, achieved their target. The average insulin dosage required for per unit HbA1c reduction was significantly different among the groups according to duration of type 2 diabetes mellitus ( p < 0.05). Among patients who achieved HbA1c <7 %, proportion of patients with hypoglycemia in the ≥20 years group was higher than that in the <10 years, 10 to <20 years groups. Early insulin administration provided a better glycemic control with less insulin dosage and lower frequency of hypoglycemic events. Thus, early insulinization might hold the key to better management of type 2 diabetes mellitus. [ABSTRACT FROM AUTHOR]

Background: The nature of cost-saving effects of early referral to a nephrologist in patients with chronic kidney disease (CKD) is not fully evaluated. We evaluated the health care costs before and after dialysis according to the referral time. Methods: A total of 879 patients who were newly diagnosed as having end-stage renal disease from August 2008 to June 2011 were prospectively enrolled. The early referral (ER) group was defined as patients who were referred to a nephrologist more than a year before dialysis and had visited a nephrology clinic 2 or more times. Patients whose referral time was less than a year were considered the late referral (LR) group. Information about medical costs was acquired from the claim data of the Korea Health Insurance Review and Assessment Service. Results: The total medical costs during the first 12 months after the initiation of dialysis were not different between the 526 ER patients and the 353 LR patients. However, the costs of the ER patients during the first month were significantly lower than those of the LR patients (ER vs. LR: 3029±2219 vs. 3438±2821 US dollars [USD], P = 0.025). The total 12-month health care costs before the initiation of dialysis were significantly lower in the ER group (ER vs. LR: 6206±5873 vs. 8610±7820 USD, P<0.001). In the multivariate analysis, ER significantly lowered the health care costs during the 12 months before (2534.0±436.2 USD, P<0.001) and the first month (428.5±172.3 USD, P = 0.013) after the initiation of dialysis. Conclusions: The ER of patients with CKD to a nephrologist is associated with decreased medical costs during the pretreatment period of renal replacement therapy and the early period of dialysis initiation. [ABSTRACT FROM AUTHOR]

Background Intracranial hemorrhage ( ICH) is a rare birth injury in term infants. Newborn infants with cephalohematoma ( CH) associated with ICH, however, have frequently been found incidentally at Kyungpook National University Hospital; many of them had no neurological symptoms. The aim of this study was to evaluate the clinical manifestations of ICH in newborn infants with CH. Methods Newborn infants with CH in the neonatal intensive care unit were retrospectively evaluated. During period I (5 years), neuroimaging (brain computed tomography and magnetic resonance imaging) was performed when intracranial abnormalities were suspected. During period II (36 months) neuroimaging was performed when CH > 5 cm in diameter was present. Results During period I, seven out of 19 infants who underwent neuroimaging had ICH (36.8%) including two epidural hemorrhages ( EDH). During period II, 18 out of 27 infants who underwent neuroimaging had ICH (66.7%), including two EDH. There was no significant difference in the clinical manifestations between infants with and without ICH. In 10 cases of CH accompanied with a linear skull fracture, nine had ICH, including all cases of ICH that needed intervention. Conclusions The association of ICH appears to be common in newborn infants with CH; particularly in infants with CH accompanied with a skull fracture, the rate of ICH was very high, and all cases of EDH requiring intervention were associated with skull fracture. Therefore, evaluation of accompanying skull fracture should be required in infants with CH, and, in cases of skull fracture, neuroimaging should be considered. [ABSTRACT FROM AUTHOR]

Statement of the Problem There is a reported gap between the relative satisfaction of the clinician and patient after a root coverage procedure. In addition, there may also be a disparity between objective esthetic evaluation tools and subjective satisfaction. Methods This study included 58 sites in 31 patients who had undergone root coverage procedures. The percentage of root coverage and the root coverage esthetic score system were used as objective measurements. A questionnaire with a five-point ordinal scale was used for subjective evaluation. Initial recession depth and width, Miller classification, tissue biotype, treatment procedures, and follow-up periods were considered as associated factors. Results After a period of at least 6 months from the procedure, the patient-perceived outcome showed a better match with the root coverage esthetic scoring system than the percentage of root coverage alone. A lower value for objective outcome was obtained for a deeper gingival recession and higher Miller class, but the subjective outcome displayed a steady trend. All four esthetic results were at their lowest after an epithelialized free soft tissue graft. Conclusion An esthetic outcome according to patient satisfaction was not always consistent with that determined by professional scoring. In addition, partial root coverage may be viewed as a positive outcome by patients and clinicians in cases of deep gingival recession and high Miller class. Clinical Significance This study evaluates the esthetic outcome of root coverage procedures using an objective method, including the percentage of root coverage, root coverage esthetic scoring system, and subjective assessment by patient and clinician-based questionnaires. The results will be helpful for the understanding of the differences that exist in esthetic satisfaction. [ABSTRACT FROM AUTHOR]

Korean water quality managers are required to promptly develop national assessment standards for freshwater sediment quality due to the Four Major River Restoration Project in Korea in 2009. We conducted this study to develop sediment management standards (SMSs), determining obviously and severely polluted sediment, which could have adverse impacts on water quality and aquatic ecosystem. The SMSs values were derived from the 95th percentile of concentration distribution for organic matter and nutrients in sediment quality database. For the SMSs of metals, foreign sediment quality guidelines (SQGs) were adopted. As a result, 13 % for loss on ignition (LOI), 1,600 mg/kg for total phosphorus (TP), and 5,600 mg/kg for total nitrogen (TN) were set as the SMSs for freshwater sediment in Korea. These values were higher than the range of heavily polluted sediment from USEPA Region 5 guideline derived by the similar approaches for the Great Lakes harbor sediments, and similar or lower than the severe effect level (SEL) from provincial sediment quality guideline (PSQG) of Ontario, Canada by screening level concentration (SLC) approach. However, SMSs in the present study are appropriate considering the concentration ranges and the Korean SMSs' definition for freshwater sediments in Korea. The Puget Sound marine sediment cleanup screening level (CSL) in Washington State, USA were adopted as the Korean SMSs for As (93 mg/kg), Cd (6.7 mg/kg), Cr (270 mg/kg), Cu (390 mg/kg), Pb (530 mg/kg), and Zn (960 mg/kg) in freshwater sediments. Hg concentration (0.59 mg/kg) of CSL was too low to determine the polluted freshwater sediments in Korea, and the SEL of Ontario, Canada for mercury concentration (2 mg/kg) was selected as the SMS for Hg. These values were found reasonable through the assessment of applicability with the datasets from locations directly affected by obvious point sources. These results indicate that SMSs for organic matter, nutrient, and metals derived within the present study can successfully determine obviously and severely polluted sediment in Korea. However, the SMSs have limits to specifically determine the effects of polluted sediment on water quality and aquatic ecosystem in Korea. Thus, we will revise and specify SMSs considering those effects and further sediment quality assessment framework in the near future. [ABSTRACT FROM AUTHOR]

Background: The impact of dialysis modality on survival is still somewhat controversial. Given possible differences in patients’ characteristics and the cause and rate of death in different countries, the issue needs to be evaluated in Korean cohorts. Methods: A nationwide prospective observational cohort study (NCT00931970) was performed to compare survival between peritoneal dialysis (PD) and hemodialysis (HD). A total of 1,060 end-stage renal disease patients in Korea who began dialysis between September 1, 2008 and June 30, 2011 were followed through December 31, 2011. Results: The patients (PD, 30.6%; HD, 69.4%) were followed up for 16.3±7.9 months. PD patients were significantly younger, less likely to be diabetic, with lower body mass index, and larger urinary volume than HD patients. Infection was the most common cause of death. Multivariate Cox regression with the entire cohort revealed that PD tended to be associated with a lower risk of death compared to HD [hazard ratio (HR) 0.63, 95% confidence interval (CI) 0.36–1.08]. In propensity score matched pairs (n = 278 in each modality), cumulative survival probabilities for PD and HD patients were 96.9% and 94.1% at 12 months (P = 0.152) and 94.3% and 87.6% at 24 months (P = 0.022), respectively. Patients on PD had a 51% lower risk of death compared to those on HD (HR 0.49, 95% CI 0.25–0.97). Conclusions: PD exhibits superior survival to HD in the early period of dialysis, even after adjusting for differences in the patients’ characteristics between the two modalities. Notably, the most common cause of death was infection in this Korean cohort. [ABSTRACT FROM AUTHOR]

The use of low-rank coal (physical and combustion characteristics are different from those of high-rank coal) is rapidly expanding both in Korea and globally owing to economic constraints; fully understanding the impact of low-rank coal on combustion and emission processes is thus imperative. Observations from several studies on low-rank coal are reviewed in this paper; these studies were conducted at Pusan clean coal center (PC 3) with entrained flow reactors (laminar flow reactor and drop tube furnace). This study provides several contributions to the analysis of the combustion and emission characteristics of low-rank coal. Such contributions include the establishment of a simplified prediction model of burning coal and analysis of the effect of particle size and environmental conditions. A numerical model that incorporates the chemical percolation devolatilization sub-model is also developed, and the effect of volatile matter and in-furnace blending method is investigated. Results obtained from analyzing low rank-coal and the developed models provide insights into the application of low-rank coal in power plants. [ABSTRACT FROM AUTHOR]

Background: Nonsurgical biliary drainage is considered as a priority for obstructive jaundice associated with unresectable hepatocellular carcinoma (HCC). Successful drainage allows the patient to receive antitumor therapy, such as transarterial chemoembolization (TACE). However, only limited data are available on clinical outcomes in patients who treated biliary drainage with subsequent TACE. Objective: This study evaluated the clinical outcome of biliary drainage with subsequent TACE in unresectable HCC patients with obstructive jaundice. Design: This was a retrospective study. Setting/subjects: A total of 60 patients received endoscopic biliary drainage (ERBD) or percutaneous transhepatic biliary drainage (PTBD) in two tertiary care referral centers. Measurements: Successful drainage and survival were measured. Results: Successful drainage was achieved in 39 (65%) patients. The median survival of 39 patients in whom successful drainage was achieved, regardless of which procedure was performed, was much longer than that of 21 patients without successful drainage (147 days versus 38 days, respectively, P<.001). In particular, the median survival was longer in 17 patients who underwent TACE after achieving successful drainage than in 22 patients who were treated conservatively after achieving successful drainage (410 days versus 77 days, respectively, P<.001). Multivariable analysis in 39 patients in the successful drainage group showed that TACE (hazard ratio 0.15; 95% confidence interval 0.05-0.45, P=.001) was an independent predictive factor of a favorable outcome. Conclusions: Effective palliation by successful biliary drainage with subsequent TACE might prolong the survival in patients with obstructive jaundice caused by unresectable HCC. [ABSTRACT FROM AUTHOR]

Rotavirus gastroenteritis is the leading cause of severe acute gastroenteritis in children worldwide and is associated with high hospitalization and mortality rates in children younger than 5 years of age. Vaccination is necessary to prevent rotavirus infection. Two live attenuated and orally administered rotavirus vaccines became commercially available in Korea. The aim of this study is to describe epidemiological changes in rotavirus gastroenteritis after the introduction of rotavirus vaccines in Korea. The medical records of 11,199 children younger than 5 years of age and hospitalized for acute gastroenteritis from August 2007 to July 2010 in eight Korean hospitals were reviewed. Rotavirus was detected in stool samples obtained from 2,959 children (26.42 %). The authors evaluated the percentage of rotavirus gastroenteritis among all acute gastroenteritis hospitalizations in eight hospitals located in different geographical areas and analyzed epidemiological changes in rotavirus gastroenteritis according to age, geographical area, and season. According to the findings, the percentage of rotavirus gastroenteritis showed a decrease in children eligible for vaccination during the study period. After introduction of the vaccine, reduced rates of rotavirus detection were observed in all of the geographical areas, and the greatest reduction was observed in Seoul. In Seoul, there was a marked delay of the rotavirus season. Conclusion: Epidemiologic changes in Korea after the introduction of rotavirus vaccine are consistent with changes observed in other countries. [ABSTRACT FROM AUTHOR]

Objectives. Many patients develop dental treatment-related symptomatic trigeminal neuralgia. However, the effectiveness of pulsed radiofrequency ( PRF) treatment and conventional radiofrequency thermocoagulation ( RFTC) for treatment of this disorder has not been determined. This retrospective study was conducted to compare the effectiveness and complications of PRF and RFTC in these patients. Methods. Fifty-four patients who experienced the onset of symptomatic trigeminal neuralgia after a dental treatment were managed by PRF or RFTC. Data were collected by reviewing their medical records and conducting a questionnaire. Patients' characteristics, the dental procedures that caused the trigeminal neuralgia, the baseline and posttreatment pain intensities, duration of pain relief, complications, and satisfactions to the treatment were evaluated. Results. Pain intensities were lower at 1 week (3.0/10 vs 6.4/10), at 1 month (2.5/10 vs 5.9/10), 3 months (2.6/10 vs 5.5/10), 6 months (3.1/10 vs 7.1/10) and 1 year (4.8/10 vs 7.2/10) in the RFTC group (28 patients) than in the PRF group (26 patients) ( P < 0.05). The duration of pain relief without medication in the RFTC group (10.8 months) was longer than that in the PRF group (0 months). The incidence of complications in the RFTC group (46.4%) was higher than that in the PRF group (3.8%) ( P < 0.05). The RFTC group reported higher satisfaction ratings (3.86/5) than the PRF group (2.19/5) ( P < 0.05). Conclusions. Although the RFTC group had more complications than the PRF group, most were minor and transient, and the patient satisfaction rate with RFTC was very high. Therefore, RFTC is an effective tool for the treatment of dental procedure-induced trigeminal neuralgia. [ABSTRACT FROM AUTHOR]

Background: Refractory asthma, a subtype of asthma with uncontrolled symptoms despite antiasthma medications, is a heterogeneous syndrome with variable clinical features, presumably different etiologies, and pathophysiological mechanisms. The heterogeneity of refractory asthma, however, is poorly understood. We aimed to characterize refractory asthma and to improve our understanding of the heterogeneity of refractory asthma patients. Methods: We identified refractory asthma patients ( n = 96) as defined by the American Thoracic Society's criteria from a cohort of Korean asthma patients ( n = 2,187). Then, cluster analysis was conducted to classify subtypes of refractory asthma. Results: Among the study group, 4.4 % ( n = 96) of all asthma patients had refractory asthma. Cluster analysis identified four distinct groups of refractory asthma. Age at onset was younger in clusters 1 and 2 than in clusters 3 and 4. Patients in cluster 1 had the most well-preserved pulmonary function; patients in cluster 2 had a female predominance and the most severe airway obstruction; patients in cluster 3 were mostly female and had the most enhanced bronchial hyperresponsiveness; and patients in cluster 4 were most male and tended to be cigarette smokers. Conclusions: The current results suggest that refractory asthma is a heterogeneous syndrome and could be classified into four subtypes. Underlying pathogenesis and therapeutic approaches may differ for the different subtypes and further research is needed. [ABSTRACT FROM AUTHOR]

Objective. To evaluate the role of IL-32 in granulomatosis with polyangiitis (GPA) patients and the relationship between IL-32 and disease activity, as PR3 has the ability to bind and activate IL-32, which has been described as a novel cytokine that induces inflammatory cytokines.Methods. We investigated the level of IL-32, PR3, TNF-α and IL-6 in GPA patients by using ELISA. Northern blot was used to analyse the level of IL-32 mRNA in leucocytes of GPA patients. The intracellular colocalization of IL-32 and PR3 in leucocytes was examined by IF staining.Results. We observed that IL-32 and PR3 levels in GPA patients were increased significantly when compared with normal individuals and each was tightly associated (P < 0.001). Northern blot analysis revealed that the mRNA level of IL-32 was prominently elevated in leucocytes of GPA patients. The intracellular colocalization of IL-32 and PR3 in leucocytes from GPA patients vs normal individuals was verified by IF staining.Conclusion. IL-32 level was elevated in GPA patients but its level was changed by treatment response. IL-32 could be an index in GPA and play a role in the aetiology of GPA. [ABSTRACT FROM AUTHOR]

Aims Both strain and strain rate (SR) measure the regional myocardial deformation and can assess phasic left atrial (LA) function. However, there is still a lack of evidence for their volume independency. In this study, strain and SR determined by tissue Doppler imaging were used to evaluate the effect of preload reduction in end-stage renal disease patients who were undergoing regular haemodialysis (HD). Methods and results Forty-one subjects who underwent transthoracic echocardiography just before and after HD were enrolled. LA strain was measured during late systole, and LA peak tissue velocity and SR were measured during systole and during early and late diastolic periods. The values of tissue velocity, strain, and SR were obtained in the basal septal, lateral, inferior, and anterior walls of the LA. The mean strain value was 23.89 ± 7.29% at baseline and decreased to 21.88 ± 5.85% after HD (P = 0.019). SR during systole (before HD 1.55 ± 0.40; after HD 1.38 ± 0.35, P = 0.001) and early diastole (before HD −1.41 ± 0.54; after HD −1.16 ± 0.45, P = 0.001) also changed. However, the acute preload change caused by HD did not affect the peak tissue velocity (before HD −6.34 ± 1.58 cm/s; after HD −6.46 ± 1.54 cm/s, P = 0.436) and the SR (before HD −1.36 ± 0.45/s; after HD −1.34 ± 0.29/s, P = 0.621) measured during late diastole. Conclusion Both tissue velocity and SR during late diastole, representing the contractile function of the LA, are relatively preload-independent parameters and are available for the evaluation of the LA function. [ABSTRACT FROM AUTHOR]

Over the past few decades, South Korea has made remarkable achievements in education despite many obstacles. Education, in turn, has played an important role in Korea's achieving both economic development and political democracy. This article examines how South Korea expanded access to education and improved its quality. The article also identifies several tasks Korean education faces in the context of the new challenges of globalization and social polarization, and some of the broader policy implications that the Korean model of educational development has beyond South Korea. [ABSTRACT FROM AUTHOR]

Conclusion: Reconstruction of a large anterior skull base defect (SBD) with the nasoseptal flap (SF) is feasible in Asians. We consider the width of the SF to be the determining factor. Increasing flap width by incorporating the mucoperiosteum of the nasal floor can compensate for the relatively small septum in Asians. Objectives: To assess the feasibility of the SF for reconstruction of large anterior SBD in Koreans, and attempt to provide tips for improving its design. Methods: Radioanatomic measurements and intraoperative findings were analyzed. Specific skull base landmarks were measured to estimate the anticipated SBD and actual SBD. The length and width of the potential SF dimension was also measured and compared with the defect size to assess its feasibility. Results: The lengths of the actual SBDs were longer than those of anticipated SBDs in all patients, while the width of actual SBDs showed less discrepancy. Length and anterior width of the potential SF exceeded the needed SF dimensions in two patients, while the posterior width of potential SF fell short of the needed dimension. In both patients, the length of harvested SF was long enough to repair the entire length of SBD, while shortage of SF width was encountered in one patient. [ABSTRACT FROM AUTHOR]

Objectives Implant osteotomy yields a substantial amount of bone in the form of bone chips entrapped within drill flutes, and can provide a promising cell source for tissue engineering. The aims of this study were to isolate human alveolar bone-derived stromal cells ( hABCs) obtained during implant osteotomy, and to evaluate osteogenic differentiation capacity of hABCs. Material and methods Bone chips were obtained by minimally irrigated implant drilling technique from 10 human donors. Isolated cells were studied with respect to their colony-forming efficiency, surface marker expression by immunofluorescence staining, fluorescence-activated cell sorting analysis and self-renewal potency. To verify the differentiation activity, in vitro osteogenic and adipogenic gene expressions were evaluated by reverse transcription-polymerase chain reaction, and in vitro formation of mineralized nodule and adipocytes was also evaluated. In vivo bone-forming activity was assessed by ectopic transplantation in immunocompromised mice ( n = 5). Results Human alveolar bone-derived stromal cells population with characteristics of mesenchymal stem cells was present in the isolated cells. Upon hABC transplantation, significant ectopic bone formation was induced with the characteristics of fully matured bone tissue. Conclusion The data support the feasibility of using hABCs as a source of stem cells for dentoalveolar bone tissue reconstruction. The cell source has an advantage that the hABCs can be easily acquired during implant surgery. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to describe in detail the gross anatomy of the nasolacrimal apparatus in relation to the lateral nasal wall by the various steps of cadaver dissection and to measure the distances of surgically important landmarks from relevant structures to improve the safety and efficiency of endoscopic surgical procedures. Methods: Thirty-six half-heads of embalmed Korean adult cadavers were dissected under a surgical microscope. After removal of the nasal septum, the lateral wall of the nasal cavity was examined. Results: The orifice of the nasolacrimal duct (NLD) was most frequently observed in the form of a vertical sulcus in 14 cases (39%) and the lacrimal fold was present in 28 cases (77.8%). A total of 15 morphometric items between the orifice of the NLD and the adjacent anatomical structures were measured. The location of the orifice of the NLD was observed at a mean of 17.5 ± 3.1 mm from the limen nasi, 22.8 ± 4.8 mm from the anterior nasal spine, and 21.4 ± 3.5 mm from the axilla of the middle nasal concha. In the positional relationships, the most frequent finding was that the lacrimal sac was posterior to the axilla of the middle nasal concha in 23 cases (64%), and overlap of the NLD with the maxillary line was observed in 24 cases (67%). Conclusions: This study was conducted to accumulate anatomic data on the lacrimal sac and duct with regard to the positional relationships among the surrounding structures to establish the information for use in endoscopic dacryocystorhinostomy. [ABSTRACT FROM AUTHOR]

For this study, an evaluation tool focusing on the Polish history was developed to measure the academic performance of college students who major in the Polish language in Korea. The purpose of this study was to investigate the eff ects of the tool on students' academic performance aft er applying it in a classroom setting. The tool consisted of three types of questions, which were administered before and aft er the application of the tool to 108 students taking a Polish history course. The results of the study serve as a foundation for revitalizing research on Poland and Polish language education, as well as for improving students' academic performance. [ABSTRACT FROM AUTHOR]

Background. The local peritoneal effects of low-glucose degradation product (GDP)-containing peritoneal dialysis fluid (PDF) have been extensively described. However, the systemic effects of prolonged prescription of these solutions are unknown. This study aimed to evaluate the effects of neutral pH and low-GDP PDF on systemic inflammation and endothelial dysfunction markers in peritoneal dialysis (PD) patients. Methods. This is a multicenter, open labeled, randomized controlled trial including one hundred fifty-two patients initiating continuous ambulatory peritoneal dialysis for end-stage renal disease from seven centers in Korea. Participants were randomly allocated to conventional PDF (Stay safe®; Fresenius Medical Care, Bad Homburg, Germany) or low-GDP PDF (Balance®; Fresenius Medical Care) and were followed for 1 year. Primary outcome variable was the inflammation and endothelial dysfunction index (IEDI), a composite score derived from serum levels of soluble intercellular adhesion molecule (sICAM)-1, soluble vascular cellular adhesion molecule (sVCAM)-1 and high-sensitivity C-reactive protein (hs-CRP). sICAM-1, sVCAM-1, residual renal function (RRF), peritoneal membrane transport characteristics, ultrafiltration volume and nutritional parameters were measured as secondary outcome variables. Results. Of 152 patients randomized, 146 (low-GDP: conventional PDF, 79:67) patients entered the trial (46% male, 53% with diabetes mellitus). At 12-month follow-up, the low-GDP group had significantly lower levels of IEDI, sICAM-1 and sVCAM-1 compared to the conventional group; hs-CRP was not different between groups. Peritoneal transport characteristics, RRF, nutritional parameters, incidence of peritonitis and death-censored technique survival were not different between groups. Conclusion. Neutral pH and low-GDP PDF likely produce fewer changes in markers of endothelial dysfunction compared to conventional PDF in incident PD patients. [ABSTRACT FROM PUBLISHER]

This paper aims to determine whether corporate governance affects manager's real operating or investment decision to control reported earnings. Through data analysis of firms listed on the Korean stock exchange, it was found that the aggregated measure of real activity-based earnings management decreases as the size of board is larger or as a greater proportion of external directors sit on the board. Those findings are almost the same, whether a corporate governance index composed by each BOD characteristics is employed, or problem caused by endogenous relationships among variables is controlled. The results provide the first empirical evidence that real activity-based earnings management is influenced by corporate governance structure. This focus on real activity-based earnings management suggests new avenues for research on corporate governance. The results offer some insights for policy makers interested in promoting legislation to ensure strong corporate governance in their nation. [ABSTRACT FROM PUBLISHER]

Background. In 2009, the Oxford classification was developed as a pathological classification system for immunoglobulin A nephropathy (IgAN) to predict the risk of disease progression. The aim of this retrospective study was to evaluate the clinical and pathologic relevance of the Oxford classification in Korean patients with a pathologic diagnosis of IgAN. Patients and methods. We reviewed the renal pathology archives from January 2000 to December 2006 at Seoul St Mary’s Hospital in Korea and identified 273 patients, who were diagnosed as having IgAN. We enrolled 197 patients who were available for further clinicopathologic analysis. All cases of IgAN were categorized according to the WHO classification, the semiquantitative classification and the Oxford classification. These pathologic classifications were compared. The clinical and laboratory findings at the time of biopsy were compared with those at the end of the follow-up according to the Oxford classification. Results. When three pathologic classifications were compared, M1, S1, E1, T1 or T2 were associated with a higher score in the activity index. S1, T1 or T2 were associated with a higher score in the chronicity index and a higher grade in the WHO classification. The clinical and laboratory findings were compared according to the Oxford classification. At the time of biopsy, the proteinuria in patients with M1 was more than that of M0 (P = 0.035). At the end of follow-up, the number of antihypertensive drugs taken among patients with M1 was greater than that of patients with M0 (P = 0.001). At the time of biopsy, the proteinuria of patients with S1 was greater than that of S0 patients (P = 0.009). At the end of follow-up, the number of patients who received immunosuppressants was increased as the grade of T increased (P = 0.000). At the end point of the follow-up, the estimated glomerular filtration rate (eGFR) decreased as the grade of T increased (P = 0.008). The time-average proteinuria after adjusting the initial proteinuria increased significantly with increasing degree of T (P = 0.000). Levels of tubular atrophy/interstitial fibrosis were predictive for survival from end-stage renal disease or of having a 50% reduction of eGFR. Conclusion. The pathologic variables of the Oxford classification correlated significantly with other classifications (the WHO classification and the semiquantitative classification). The Oxford classification is a simple method for predicting renal outcome and differentiating between active and chronic lesions. We suggest that the Oxford classification offers an advantage for determining treatment policy for patients with IgAN. [ABSTRACT FROM PUBLISHER]

Background. Chronic kidney disease (CKD) is an increasing public health problem. However, there have been limited data on the trend of CKD prevalence, along with the changes of health-related behaviors and other chronic diseases in an adult Korean population.Methods. Data from the Korean National Health and Nutrition Examination Survey in 2005 and 2007 were analyzed. The study subjects comprised 8400 participants aged ≥20 years with creatinine data. CKD was defined as estimated glomerular filtration rate (GFR) <60 mL/min/1.73m2. GFR was estimated by the abbreviated Modification of Diet in Renal Disease equation.Results. The CKD prevalence was significantly decreased from 2005 to 2007 (8.8 versus 7.2%; P = 0.010). The prevalence of hypertension was stable but that of diabetes was increased. The proportion of blood pressure (BP) <130/80 mmHg in the whole population, and HbA1c <7% in the diabetic participants was increased from 2005 to 2007. Participants in 2007 walked more than those in 2005. The proportion of current smoking and sodium/energy/protein excess was decreased from 2005 to 2007. In subgroup analysis, only hypertensive participants without diabetes revealed a decreasing trend of CKD.Conclusions. The CKD prevalence was decreased from 2005 to 2007. Since increased diabetes and improved diabetic control neutralized their impact on CKD, improved BP was the fundamental reason for the decrease. Various health-related behaviors may have indirectly affected the decrease of CKD through their effect in controlling BP and diabetes. [ABSTRACT FROM PUBLISHER]

Compost has been widely used in order to promote vegetation growth in post-harvested and burned soils. The effects on soil microorganisms were scarcely known, so we performed the microbial analyses in a wildfire area of the Taebaek Mountains, Korea, during field surveys from May to September 2007. Using culture-dependent and -independent methods, we found that compost used in burned soils influenced a greater impact on soil fungi than bacteria. Compost-treated soils contained higher levels of antifungal strains in the genera Bacillus and Burkholderia than non-treated soils. When the antifungal activity of Burkholderia sp. strain O1a_RA002, which had been isolated from a compost-treated soil, was tested for the growth inhibition of bacteria and fungi isolated from burned soils, the membrane-filtered culture supernatant inhibited 19/37 fungal strains including soil fungi, Eupenicillium spp. and Devriesia americana; plant pathogens, Polyschema larviformis and Massaria platani; an animal pathogen, Mortierella verticillata; and an unidentified Ascomycota. However, this organism only inhibited 11/151 bacterial strains tested. These patterns were compatible with the culture-independent DGGE results, suggesting that the compost used in burned soils had a greater impact on soil fungi than bacteria through the promotion of the growth of antifungal bacteria. Our findings indicate that compost used in burned soils is effective in restoring soil conditions to a state closer to those of nearby unburned forest soils at the early stage of secondary succession. [ABSTRACT FROM AUTHOR]

Objective This study was undertaken to generate and characterize human induced pluripotent stem cells (PSCs) from patients with osteoarthritis (OA) and to examine whether these cells can be developed into disease-relevant cell types for use in disease modeling and drug discovery. Methods Human synovial cells isolated from two 71-year-old women with advanced OA were characterized and reprogrammed into induced PSCs by ectopic expression of 4 transcription factors (Oct-4, SOX2, Klf4, and c-Myc). The pluripotency status of each induced PSC line was validated by comparison with human embryonic stem cells (ESCs). Results We found that OA patient-derived human synovial cells had human mesenchymal stem cell (MSC)-like characteristics, as indicated by the expression of specific markers, including CD14−, CD19−, CD34−, CD45−, CD44+, CD51+, CD90+, CD105+, and CD147+. Microarray analysis of human MSCs and human synovial cells further determined their unique and overlapping gene expression patterns. The pluripotency of established human induced PSCs was confirmed by their human ESC-like morphology, expression of pluripotency markers, gene expression profiles, epigenetic status, normal karyotype, and in vitro and in vivo differentiation potential. The potential of human induced PSCs to differentiate into distinct mesenchymal cell lineages, such as osteoblasts, adipocytes, and chondrocytes, was further confirmed by positive expression of markers for respective cell types and positive staining with alizarin red S (osteoblasts), oil red O (adipocytes), or Alcian blue (chondrocytes). Functional chondrocyte differentiation of induced PSCs in pellet culture and 3-dimensional polycaprolactone scaffold culture was assessed by chondrocyte self-assembly and histology. Conclusion Our findings indicate that patient-derived synovial cells are an attractive source of MSCs as well as induced PSCs and have the potential to advance cartilage tissue engineering and cell-based models of cartilage defects. [ABSTRACT FROM AUTHOR]

Abstract: In an effort to increase the credibility of human embryonic stem cell (hESC) lines established in Korea, obligatory registration was introduced by the Bioethics and Safety Act 2008, effective as of January 1, 2010. The DNA fingerprint, chromosome stability, expression of pluripotency markers, and contamination of mycoplasma of the submitted lines were analyzed by Korea Centers for Disease Control and Prevention (KCDC). The characterization data and ethical aspects, such as informed consent for donation of surplus embryos, were reviewed by a 10-member advisory review committee for stem cell registry. A total of 55 domestic hESC lines were submitted for registration in 2010; among them 51 were registered. Among these submitted lines, 26 were additionally characterized by KCDC, while 25 lines previously characterized by the Ministry of Education, Science and Technology were not additionally analyzed by KCDC. Registration completed an oversight system for embryo research by registering the products of licensed embryo research projects, making embryo research more transparent in Korea. Information about hESC lines is available at the website of the Korea Stem Cell Registry (kscr.nih.go.kr). [Copyright &y& Elsevier]