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Emulsion absorbents based on NaOH solution (ES–NaOH) consist of carbon nanotubes (CNTs) and silicone oil. ES–NaOH can control the CO2 capture capacity and rate with the concentration of CNTs and NaOH, and can be applied indoors like an adsorbent.

Power efficiency of photovoltaic (PV) cell is significantly affected by the cell temperature. Herein, a passive cooling unit comprising inexpensive materials is developed for perfromance improvement of the PV cell. The water-saturated zeolite 13X is coated on the back side of the PV cell, and ammonium nitrate is dispersed as a layer. When thermal radiation is supplied, water is desorbed from zeolite 13X (primary latent cooling), and also dissolves ammonium nitrate to induce secondary endothermic reaction cooling. The cooling unit is operated based on the moisture sorption performance of mesoporous materials, which is inversely proportional to the cell temperature, and the solubility of endothermic reaction pairs increases proportionally with temperature. It is a reversible process in which ammonium nitrate is crystallized when the temperature is low at night, and water is adsorbed back to zeolite 13X. The average temperature of the PV cell can be reduced by approximately 14.9°C during the day, and the cooling energy density reaches 2,876 kJ/kg. Based on the life cycle cost analysis, the cost of power generation can be reduced by 5.1%, and the power efficiency is improved by 7.5%. A PV cell with the passive cooling unit will be a solution for efficient PV electric generation.

Tubular tissues exist in various forms purported for blood supply, waste secretion, etc. to aid proper function and maintenance of the human body. Under pathological conditions, however, these tissues may undergo stenosis. A major surgical treatment for stenosis is to implant a medical device called a stent which aims to expand the narrowed tissue and maintain its patency. Most stents are currently made from metals; despite their high mechanical strength, however, interactions with the host tissue often results in restenosis and stent fracture. To solve these problems, a bioresorbable stent (BRS) is proposed as a next generation stent. In this study, a rotating rod combined 3D printing system was developed to fabricate various types of BRSs. In addition, we confirmed that a 1.5 year long-term release of paclitaxel is possible using polymeric materials. Moreover, a stent loaded with contrast powder was fabricated and was successfully viewed under fluoroscopy. The stent was then implanted in the iliac arteries of pigs and no adverse events were observed for up to 8 weeks.

Background/Aims: The aims of the present study were to determine the frequency of interval colorectal cancers (CRCs) after surveillance colonoscopy and to compare the clinic-pathologic features and survival outcomes with those of non-interval CRCs. Methods: From January 2003 to December 2013, 66,016 follow-up colonoscopies for 38,412 patients performed within recommended time were reviewed retrospectively based on data from 11 tertiary hospitals in South Korea. To compare clinicopathologic features and survival rates for interval CRC, 106 patients with non-interval CRC matched in age and gender were included. Results: Among the 66,016 colonoscopies performed within the surveillance period, 63 cases (63/66,016) of interval CRC were detected, and 53 were finally included in the analysis. The mean age was 69.9±8.8 years, and the male to female ratio was 1.94:1. Although the occurrence rate of cancer in the right side colon was higher than that of non-interval CRC, interval CRCs were predominantly left sided. Other clinicopathologic features and overall survival were not significantly different between the two groups. Missed lesion was suspected to be the most common cause (29 cases, 54.7%). Conclusions: The frequency of interval CRC among patients who had undergone a surveillance colonoscopy was 0.095%. While sharing some similar clinical features and survival outcomes, interval CRCs in Korea developed more often in males and on the left side in contrast to results from Western studies. (Gut Liver 2018;12:537-543)

Device-related problems of drug-eluting stents, including stent thrombosis related to antiproliferative drugs and polymers, can cause adverse events such as inflammation and neointimal hyperplasia. Stent surface modification, wherein the drug and polymer are not required, may overcome these problems. We developed hydrophilic polyethylene glycol (PEG)-coating and hydrophobic octadecylthiol (ODT)-coating stents without a drug and polymer and evaluated their histopathologic response in a porcine coronary restenosis model. PEG-coating stents (n = 12), bare-metal stents (BMS) (n = 12), and ODT-coating stents (n = 10) were implanted with oversizing in 34 porcine coronary arteries. Four weeks later, the histopathologic response, arterial injury, inflammation, and fibrin scores were analyzed. A p value

In the present study, surface modification of Fe3O4 particles with ascorbic acid (AA-Fe3O4) is carried out to enhance the absorption and regeneration performances of Fe3O4 nanoabsorbents with magnetic fields. The surface modified AA-Fe3O4 particles compensate for the defects of commercial magnetic nanoparticles by enhanced hydrophilicity and increased surface area. Methanol, which is widely used as a conventional industrial physical absorbent of CO2 capture, is used as a base fluid; however, the absorption process must be operated at low temperature for high absorption performance. In addition, a substantial amount of energy input is required to reach the regeneration operating temperature. Manufactured AA-Fe3O4 is analyzed using various analysis methods to assess absorption characteristics. Furthermore, a property analysis of 0.005 vol% AA-Fe3O4 dispersed in methanol shows that a high dispersion stability is obtained compared to 0.005 vol% commercial Fe3O4 dispersed in methanol. An evaluation on the performance of AA-Fe3O4 at 25 °C in the presence of external rotating magnetic fields shows an enhancement of 23.3 % in absorption. According to the specific energy consumption analysis, it is concluded that AA-Fe3O4/methanol nanoabsorbents will be beneficial for industrial applications in efficient energy savings for CO2 capture.

Considering the limitations of indoor ventilation owing to air pollution, CO2 concentration rises rapidly to 3000 ppm, which is a level that can affect human health. It is essential to develop materials to reduce naturally occurring CO2 in the buildings. Herein, a nano-encapsulated solvent (NES) via Pickering emulsion is proposed for indoor CO2 capture. NaOH aqueous solution is wrapped with hydrophobic surface-functionalized SiO2 (HS-SiO2) nanoparticles, and the corrosiveness of NaOH is not caused by HS-SiO2 wall. CO2 capture capacity of NES-NaOH is evaluated as 7.57 mmol-CO2/g-solvent which is the highest compared to other solvents including metal-organic frameworks (MOFs); it exhibits excellent structural stability in terms of temperature, time, moisture, and CO2 reaction. NES-NaOH presents high selectivity toward CO2 molecules due to the characteristics of NaOH with high gas permeability of macroporous silica wall and it is dispersed in a silicone oil harmless to human body. It is concluded that NES-NaOH can be successfully applied to air purifier filter to control the CO2 concentration in buildings.

Research on CO2 capture using nanofluids and nanoemulsions has been actively conducted in recent decades, and numerous studies have achieved improvements in the CO2 absorption performance of nanofluids and nanoemulsions. In this study, to analyze the enhancement of CO2 absorption performance achieved by nanofluids and nanoemulsions, experiments are conducted for visualizing the diffusion of CO2 inside absorbents using the shadowgraph method. The nanofluid absorbents are prepared using SiO2 solid particles, and the nanoemulsion absorbents are prepared using dodecane as the dispersed phase. The effects of concentration are analyzed through the absorption experiments performed for each concentration. The diffusion coefficient is calculated experimentally and theoretically based on the results of the visualization tests. The absorption of CO2 begins at the absorbent’s upper interface when the CO2 gas is stationary or moving. The highest absorption is observed at 0.05 vol% of nanoparticles. The absorption performances of the nanofluid and nanoemulsion absorbents are improved by 23.05% and 26.80%, respectively. As CO2 is absorbed, the absorbent density changes and the Rayleigh convection becomes prominent, resulting in a plume-like flow. The plume formation and growth stages are subdivided into four stages, and both absorbents are compared. The visualization test results indicate that the hydrodynamic effect is a dominant factor in improving nanofluids’ mass transfer and nanoemulsions.

Brunner's gland hamartomas are small benign lesions that are most commonly found in the bulb of the duodenum. They are very uncommon, and most are found incidentally during upper gastrointestinal series or esophagogastroduodenoscopy. The lesions tend to be asymptomatic, but patients may present with symptoms of duodenal obstruction or hemorrhage secondary to ulceration. Histologically, a Brunner's gland hamartoma consists of the components of Brunner's gland cells, as well as glandular, adipose and muscle cells. In this study, we report the case of a 30-year-old man who presented with upper gastrointestinal bleeding and obstructive symptoms due to a giant Brunner's gland hamartoma in the duodenal bulb. The hamartoma was successfully removed by endoscopic resection. No significant complications were observed. Microscopically, the lesion was found to be entirely composed of variable Brunner's glands and adipocytes.

Background/Aims: Crohn’s disease (CD) is a chronic inflammatory bowel disease that presents with variable features and repeated disease aggravation. The incidence of CD is increasing in Korea. We evaluated the clinical features of CD in a study population in Busan and Gyeongnam, Korea. Methods: A hospital-based analysis included 619 patients diagnosed with CD between March 1986 and February 2013 from seven tertiary care hospitals in Busan and Gyeongnam. Individual case records were reviewed with regard to age at diagnosis, sex, disease location, disease behavior, and medical and surgical treatments received during the follow-up period. Results: The cumulative frequency of patients diagnosed with CD revealed a continued increase in the number of cases reported yearly. The male-to-female ratio was 2.5:1 and the median age at diagnosis was 24 years. At diagnosis, 114 (18.4%) had isolated small bowel disease, 144 (23.3%) had isolated colonic disease, and 358 patients (57.8%) presented with disease in the small bowel and colon. The number of patients presenting with stricturing or penetrating disease behavior was 291 (47%) at the final evaluation. In total, 111 (17.9%) patients underwent intestinal resections. Conclusions: A continued increase in the number of patients diagnosed with CD was found in Busan and Gyeongnam as observed in other regions. We report results similar to that of other Korean studies in terms of sex distribution, age, and location of disease. (Intest Res 2016;14:30-36)

The enzymatic digestion of lipoaspirate is used to isolate the heterogeneous stromal vascular fraction (SVF) that contains the adipose-derived stromal cells (ASCs). Several automated SVF isolation systems are used to operate standard technical procedures and avoid human errors. However, the yield of isolated cells and the residual collagenase activities of the SVF samples obtained from automated systems are not satisfactory compared to those from manual isolation methods. In this study, we evaluated the efficiency and the reliability of a new automated SVF isolation system in which the bowl was designed in the shape of a radial protrusion at each angle (a top-type bowl). The viability and yield of cells and the residual collagenase activities of SVFs obtained in a top-type bowl were compared with the SVFs obtained in a conventional bowl. We achieved a significantly higher yield of cells and decreased residual collagenase activity in the SVFs obtained from a top-type bowl (18.0 × 105 cells/mL of fat) compared to a conventional bowl (2.3 × 105 cells/mL). There was no significant difference in the cell viability between the two groups. These results suggest that the automated SVF isolation system with an improved bowl structure will potentially yield higher numbers of nucleated cells and decreased residual collagenase activity compared to conventional automated systems in cell-based clinical trials.

Background/Aims It is well known that 5-aminosalicylic acid (5-ASA) is the standard first-line treatment for ulcerative colitis (UC). Medication adherence is an important factor in the treatment of UC. We aimed to identify predictors of low adherence to oral 5-ASA in Koreans with UC. Methods Between July 2017 and January 2018, we performed a multicenter, cross-sectional study across 6 University Hospitals in Korea. Medication adherence was assessed using the modified Morisky Medication Adherence Scale (MMAS-8) questionnaire. Our study included 264 patients with UC. Patients were requested to complete the self-reported MMAS-8 questionnaire and a survey assessing sociodemographic data. Adherence was categorized as low (scores

Purpose Adipose-derived stem cells (ADSCs) are known to be potentially effective in regeneration of damaged tissue. We aimed to assess the effectiveness of intracoronary administration of ADSCs in reducing the infarction area and improving function after acute transmural myocardial infarction (MI) in a porcine model. Materials and methods ADSCs were obtained from each pig's abdominal subcutaneous fat tissue by simple liposuction. After 3 passages of 14-days culture, 2 million ADSCs were injected into the coronary artery 30 min after acute transmural MI. At baseline and 4 weeks after the ADSC injection, 99mTc methoxyisobutylisonitrile-single photon emission computed tomography (MIBISPECT) was performed to evaluate the left ventricular volume, left ventricular ejection fraction (LVEF; %), and perfusion defects as well as the myocardial salvage (%) and salvage index. At 4 weeks, each pig was sacrificed, and the heart was extracted and dissected. Gross and microscopic analyses with specific immunohistochemistry staining were then performed. Results Analysis showed improvement in the perfusion defect, but not in the LVEF in the ADSC group (n=14), compared with the control group (n=14) (perfusion defect, -13.0±10.0 vs. -2.6±12.0, p=0.019; LVEF, -8.0±15.4 vs. -15.9±14.8, p=0.181). There was a tendency of reducing left ventricular volume in ADSC group. The ADSCs identified by stromal cell-derived factor-1 (SDF-1) staining were well co-localized by von Willebrand factor and Troponin T staining. Conclusion Intracoronary injection of cultured ADSCs improved myocardial perfusion in this porcine acute transmural MI model.

The present study aimed to examine potential biomarkers for the diagnosis of endometriosis. A plasma-based proteomic approach, including 2-dimentional electrophoresis and mass spectrometry, was used. Samples were obtained from patients with (n=15) and without (n=15) endometriosis, or from mice with surgically induced endometriosis. Seven spots corresponding to six differentially expressed proteins were identified in the human plasma samples. However, only haptoglobin (Hp) was identified to be significantly decreased in the plasma levels of patients with endometriosis (P

Background/Aims In the present study, we evaluated the efficacy and tolerability between same-day bowel preparation protocols using 2 sachets of Picosulfate and a 4 L split-dose polyethylene glycol (PEG) bowel preparation for afternoon colonoscopy. Methods The study had a single-center, prospective, randomized, and investigator-blinded, non-inferiority design. We evaluated bowel preparation quality according to the Ottawa scale, patient tolerability, compliance, incidence of adverse events, sleep quality, and polyp/adenoma detection rate. Results Among the 196 patients analyzed (mean age, 55.3 years; 50.3% men), 97 received the same-day regimen of 2 sachets of picosulfate (group A) and 99 received the 4 L split-dose PEG regimen (group B). The Ottawa score of the total colon was 4.05±1.56 in group A and 3.80±1.55 in group B (P=0.255). The proportion of patients having adequate bowel preparation in the same-day picosulfate group (61.5%) was slightly less than the 4 L PEG group (71.3%); however, the difference was not statistically significant (P=0.133). Tolerability of the group A regimen was superior to that of the group B regimen (P

The Alcohol Use Disorders Identification Test (AUDIT) has been found to provide an accurate measure for risk of hazardous and harmful alcohol use, as well as possible dependence. Data from 2 representative samples of 7693 adults in the Korea National Health and Nutrition Examination Survey (KNHANES) 2005 and 6276 participants in 2009 were analyzed. The overall age-adjusted prevalence of alcohol use disorder (AUD) in 2009 (38.8%) was higher than that in 2005 (32.7%), with a difference of 6.1% (95% confidence interval [CI], 2.9%–9.3%; P = .0002). Men were about 7 times as likely as women to meet the criteria for AUD (odds ratio [OR] = 7.16; 95% CI, 6.27–8.17). Current smoking was the most important correlate associated with AUD in both genders (women: OR = 6.03; 95% CI, 4.40–8.27; men: OR = 2.83; 95% CI, 2.29–3.48). Among women, unmarried (OR = 1.76; 95% CI, 1.35–2.31), less than high school education (OR = 2.71, 95% CI, 1.86–3.96), and lowest income (OR = 1.45, 95% CI, 1.06–1.97) were associated with AUD. These findings provide the most updated prevalence estimates of AUD in the Korean population and they highlight its strong association with smoking, gender differences, and lower socioeconomic status in the Korean population.

Background and objectives Thoracic endovascular aortic repair exhibits limitations in cases where the aortic pathology involves the aortic arch. We had already developed a fenestrated aortic stent graft (FASG) with a preloaded catheter for aortic pathology involving the aortic arch. FASG was suitable for elective cases. Materials and methods An aortic arch stent graft with a window-shaped fenestration (FASG-W) for supra-aortic arch vessels is suitable for emergent cases. This study aims to test a FASG-W for supra-aortic arch vessels and to perform a preclinical study in swine to evaluate the safety and efficacy of this device. Six FASG-Ws with 1 preloaded catheter were advanced through the iliac artery in 6 swine. The presence of endoleak and the patency and deformity of the grafts were examined with computed tomography (CT) at 4 weeks postoperatively. A postmortem examination was performed at 8 weeks. The mean procedure time for FASG-W was 27.15±4.02 minutes. The mean time for the selection of the right carotid artery was 5.72±0.72 minutes. Results Major adverse events were not observed in any of the 6 pigs who survived for 8 weeks. For the FASG-W, no endoleaks, no disconnection, and no occlusion of the stent grafts were observed in the CT findings or the postmortem gross findings. Conclusion The procedure with the FASG-W was able to be performed safely in a relatively short procedure time and involved an easy technique. The FASG-W was found to be safe and convenient for use in this preclinical study of swine.

We describe the fabrication of a biomimically designed superhydrophobic poly(ε-caprolactone) surface, which was obtained using a modified electrostatic process. The fabricated surface exhibits a micron-sized pyramid structure consisting of accumulated droplets and nanofibres. By using this simple one-step process, we can achieve a superhydrophobic surface having both a high water contact angle and low threshold sliding angle, similar to that of the superhydrophobic plant leaf.

Background/Aims: We aimed to evaluate survival time and prognostic factors in patients with advanced unresectable cholangiocarcinoma who have not re- ceived surgery, chemotherapy, or radiotherapy. Me- thods: A total of 1,377 patients, who were diagnosed with primary cholangiocarcinoma between 1996 and 2002, were reviewed retrospectively according to the following inclusion criteria: histologically proven pri- mary adenocarcinoma arising from the bile-duct epi- thelium, advanced unresectable stages, no severe co- morbidity that can affect survival time, and no history of surgery, chemotherapy, or radiotherapy. Results: Of the 1,377 cases reviewed, 330 patients complied with the inclusion criteria and were thus eligible to participate in this study; 203 had intrahepatic chol- angiocarcinoma and 127 had hilar cholangiocarcinoma. The overall survival time of the entire cohort (n=330) was median 3.9 months (range; 0.2 to 67.1). The sur- vival time was significantly shorter in the intrahepatic cholangiocarcinoma group (3.0±5.3 months) than in the hilar cholangiocarcinoma group (5.9±10.1 months; Kaplan-Meier survival analysis). Multivariate analysis revealed that distant metastasis was a poor prog- nostic factor for intrahepatic cholangiocarcinoma (p 3.0 g/dL was a fa- vorable prognostic factor (p=0.02), and baseline serum carcinoembryonic antigen level >30 ng/mL was a poor prognostic factor for hilar cholangiocarcinoma (p=0.01). Conclusions: The median survival of ad- vanced unresectable cholangiocarcinoma is dismal. (Gut and Liver 2009;3:298-305)

Functionally graded materials have composition gradients from one end to the other as the result of a gradual transition of the properties of different materials. The residual stress caused by the difference of coefficient of thermal expansion can be minimized using functionally graded material. Therefore, the gradient of the coefficient of thermal expansion should vary according to the compositional gradient. In this study, the coefficient of thermal expansion of each compositional layer of Ni-Al 2 O 3 functionally graded material was measured using a dilatometer. These measurements provided the material properties required to calculate the residual stress, using three-dimensional modeling for accurately predicting crack positions, since it is difficult to measure residual stress experimentally. The measurement results showed the gradual increase of the coefficient of thermal expansion from Al 2 O 3 -rich composition to Ni-rich composition. Finally, the results of calculating residual stresses using the measured coefficient of thermal expansion showed that the crack positions were predicted more accurately than those using the coefficient of thermal expansion calculated by the linear rule of mixtures. This was because the measured values include the effect of porosity of the composite, whereas the linear rule of mixtures cannot account for the porosity of each layer.

With the recent emphasis on the importance of successfully joining materials, researchers have tried to join metals and ceramics with different coefficients of thermal expansion (CTEs) by using the functionally graded material (FGM) method. This involves inserting interlayers with composition gradients that range from one material to the other, thereby minimizing the stress caused by differences in CTE values. In this study, the FGM that included 10 layers of Ni-Al 2 O 3 with eight inter-layers was studied. Previous studies have focused on controlling the composition of inter-layers and optimizing the dispersion process to prevent cracks. Thermal stress was reduced by varying the weights of the inter-layers and increasing the green-body density by using several powder sizes. The powders were well-dispersed during fabrication by using simultaneous dispersion and dry processes followed by a cold isostatic press (CIP) and pressure-less sintering in an inert atmosphere. As a result, a crack-free Ni-Al 2 O 3 FGM joint was obtained. The residual stress in each layer was calculated to predict cracks using ANSYS simulation and maximum principal stress criterion; experimental values matched simulation results. In addition, an oriented Vickers indentation test was used to assess the quality of the joint. Crack-paths were not deflected across the interface, indicating good bond strength between interfaces. Sample density was measured using the Archimedes method; the sintered joint was less dense than its theoretical density but was denser than the results obtained by using previous methods.

We fabricated a crack-free joining of Ni and Al2O3 using a functionally graded method. Because porosity reduction is important, particle size of the Ni and Al2O3 powders was varied to improve green body density and minimize shrinkage during sintering. As a result, crack-free joining of a Ni–Al2O3 sample with 10 layers was obtained. The ANSYS simulation tool was used to calculate residual stress. The hardness and modulus of each graded layer were measured using an Vickers’ indenter. The experimental values matched the simulation results, showing that this analysis is useful when residual stresses are very difficult to measure experimentally.

Joining Si3N4 and Al2O3 using 15 layers has been achieved by a unique approach that introduces SiAlON polytypoids as a functionally graded material (FGM) bonding layer. Previously, the hot press sintering of multilayered FGM with 20 layers, each 500 µm thick, has been achieved successfully. In the present study, the number of layers for FGM was reduced from 20 to 15 to increase optimization. Samples were fabricated by hot pressing at 48 MPa during the temperature ramp to 1650°C and cooling at 2°C/min to minimize residual stresses from sintering. Moreover, a finite element method (FEM) program based on the maximum principal stress theory and the maximum tensile stress theory was applied to design optimized and reduced FGM layers that produced a crack-free joint. The sample had a 3-dimensional cylindrical shape that was transformed to a 2-dimensional axisymmetric mode. By determining the expected thermal stress from the calculated elastic modulus and coefficient of thermal expansion, we were able to predict and prevent damage due to thermal stresses. These analyses are especially useful for FGM samples where it is very difficult to measure the residual stresses experimentally. Finally, oriented Vickers indentation testing was used to qualitatively characterize the strengths of the joint and the various interfaces. The indentation cracks were deflected at the SiAlON layers, implying weak interfaces. In other areas, cracks were not deflected, implying strong interfaces.

Numerical analysis method was used to reduce the number of functionally graded material (FGM) layers for joining Si3N4-Al2O3 using polytypoid interlayer by estimating the position of crack. In the past, hot press sintering of multi-layered FGMs with 20 layers of thickness 500 mm each have been fabricated successfully. In this paper, thermal residual stresses were calculated using finite element method (FEM) to find the optimized number of layers and its thicknesses of FGM joint. The number of layers for FGM was reduced to 15 layers from 20 layers. Thicknesses were varied to minimize residual stresses within the layers while reducing the number of FGM layers. The damage caused by thermal residual stress was estimated using maximum principal stress theory and maximum tensile stress theory. The calculated maximum stress was found to be axial stress of 430 MPa around 90% 12H/10% Al2O3 area. For each case, calculated strength of each FGM layer by linear rule of mixture was compared with computed thermal residual stresses. Thermal analysis results correctly predicted the position of crack, and this position agreed well with fabricated joints. Therefore, this numerical analysis method can be applied to reduced FGM layers of crack free joint. Finally, new composition profile of crack free joint was proposed using FGM method. [doi:10.2320/matertrans.MRA2007319]

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease caused by selective motor neuron death, and currently no effective treatment is available for ALS. In this study, we investigated the neuroprotective effects of pyruvate, which acts as an anti-oxidant and as an energy source. We treated G93A SOD1 transgenic mice with pyruvate (from 70 days of age, i.p., at 1000 mg/kg/week), and found that it prolonged average lifespan by 12.3 days (10.5%), slowed disease progression, and improved motor performance, but did not delay disease onset. Pyruvate treatment was also associated with reduced nitrotyrosine immunoreactivity, gliosis, and increased Bcl-2 expression in the spinal cords of G93A SOD1 transgenic mice. These results suggest that pyruvate treatment may be a potential therapeutic strategy in ALS.

Engineered polymer scaffolds play an important role in tissue engineering. An ideal scaffold should have good mechanical properties and provide a biologically functional implant site. Considering their large surface area and high porosity, nanofibers have good potential as biomimetic scaffolds. However, the main shortcomings of scaffolds consisting of nanofibers are their mechanical inability to sustain a stress environment for neotissues and shape-ability to form a variety of shapes and sizes. In this study, we produced design-based poly (e-carprolactone) (PCL) nanofiber mats using an electrospinning method with various auxiliary electrodes and an x-y moving system. To achieve stable initial solution at a nozzle tip of the electrospinning, various types of auxiliary electrodes were introduced. To characterize the effect of the electrodes in the electric-field distribution near the nozzle tip, we calculated the electric field concentration factor and compared it with the experimental results. The nanofiber mat produced using the moving x-y target system demonstrated orthotropic mechanical properties due to the fiber orientation, and human dermal fibroblasts seeded on the structure tended to grow according to nanofiber orientation. POLYM. ENG. SCI., 47:707–712, 2007. © 2007 Society of Plastics Engineers.

A 61-year-old male patient was admitted because of unexplained abdominal pain and anemia. His past medical history was unremarkable except for having taken herbal medicine to treat facial palsy two months ago. The result of health examination performed about a month ago showed increased serum aspartate and alanine aminotransferase level, and he was diagnosed with toxic hepatitis by herbal medicine. When the patient presented to the outpatient department three weeks ago, follow-up liver function test results showed improvement but he complained of abdominal pain. Despite extensive blood chemistry tests and computed tomography, the cause of pain could not be found. After much deliberation, serum lead level and herbal medicines analysis was performed based on the fact that he took herbal medicine two months ago, and he could finally be diagnosed with lead poisoning. Since the serum lead level was high enough to be indicated for lead chelating therapy, conservative management was given. When a patient with toxic hepatitis due to herbal medication presents with abdominal pain, the possibility of lead poisoning should always be taken into consideration.

The Angelicae dahuricae radix (ADR) has been used a traditional medicine to treat acne, erythema, headache, toothache, sinusitis, colds, and flu in Korea, Japan and China. Here, we report the effect of ADR on compound 48/80-induced ear-swelling and the phorbol myristate acetate (PMA) plus calcium ionophore A23187-induced inflammatory cytokine secretion in the human mast cell line, HMC-1. ADR dose-dependently inhibited the ear-swelling response induced by intradermal injection of compound 48/80, In vitro model, PMA plus A23187 significantly increased interleukin , IL-8, granulocyte macrophage colony stimulating factor (GM-CSF), and tumor necrosis factor secretion compared with media control. We also show that the increased cytokines , IL-8, GM-CSF, and level was significantly inhibited by treatment of ADR. In addition, ADR partially blocked PMA plus A23187-induced extracelluar signal-regulated kinases phosphorylation. These results suggest that ADR might explain its beneficial effect in the treatment of mast cell-mediated inflammatory diseases.

The Shannon system is generalized and the expansion of a function in the generalized Shannon system is considered. No study of a wavelet expansion exists without the assumption of ‘fast’ decay of wavelets. The wavelet ψ which is associated with the generalized Shannon system has a ‘slow’ decay. The expansion of a function in the system is shown to converge at a point which satisfies the Lipschitz condition of order α > 0. On the other hand, there is a continuous function whose wavelet expansion in the generalized Shannon system diverges. An observation of Gibbs' phenomenon is also given.

Several reports from Western countries suggest differences in the clinical features of patients with muscle specific kinase (MuSK) antibody-positive and -negative seronegative myasthenia gravis (MG). We performed the first survey in Korea of MuSK antibodies, studying 23 patients with acetylcholine receptor (AChR)-antibody seronegative MG. MuSK antibodies were present in 4 (26.7%) of 15 generalized seronegative MG patients and none of 8 ocular seronegative MG patients. All four MuSK positive patients were females, with pharyngeal and respiratory muscle weakness, and required immunosuppressive treatment. However, overall disease severity and age at onset was similar to that of MuSK-negative MG and treatment responses were equally good.

Background: Treatment of critical limb ischemia (CLI) by bypass operation or percutaneous vascular intervention is occasionally difficult. The safety and efficacy of multiple intramuscular adipose tissue-derived mesenchymal stem cells (ATMSC) injections in CLI patients was determined in the study. Methods and Results: The study included 15 male CLI patients with ischemic resting pain in 1 limb with/without non-healing ulcers and necrotic foot. ATMSC were isolated from adipose tissue of thromboangiitis obliterans (TAO) patients (B-ATMSC), diabetes patients (D-ATMSC), and healthy donors (control ATMSC). In a colony-forming unit assay, the stromal vascular fraction of TAO and diabetic patients yielded lesser colonies than that of healthy donors. D-ATMSC showed lower proliferation abilitythan B-ATMSC and control ATMSC, but they showed similar angiogenic factor expression with control ATMSC and B-ATMSC. Multiple intramuscular ATMSC injections cause no complications during the follow-up period (mean follow-up time: 6 months). Clinical improvement occurred in 66.7% of patients. Five patients required minor amputation during follow-up, and all amputation sites healed completely. At 6 months, significant improvement was noted on pain rating scales and in claudication walking distance. Digital subtraction angiography before and 6 months after ATMSC implantation showed formation of numerous vascular collateral networks across affected arteries. Conclusions: Multiple intramuscular ATMSC injections might be a safe alternative to achieve therapeutic angiogenesis in patients with CLI who are refractory to other treatment modalities. (Circ J 2012; 76: 1750 – 1760)

BACKGROUND It is unclear to what extent insulin resistance (IR) modulates the association linking obesity to alanine aminotransferase (ALT) activity elevation. METHODS We measured the homeostatic model assessment for IR (HOMA-IR) in 1591 participants aged 12-18 years from the 2008 to 2009 Korea National Health and Nutrition Examination Survey. RESULTS Overweight adolescents had an odds ratio of 7.23 [95% confidence interval (95% CI), 4.33-12.10] for an elevated ALT activity compared with normal-weight adolescents, and the corresponding risk was 23.62 (95% CI, 12.98-42.98) in obese adolescents. Adjustments for other participant factors did not substantially affect the results. The addition of the HOMA-IR data decreased the estimate for overweight adolescents by 27% and for obese adolescents, the decrease was 47%. Both obesity and IR markers remained independent predictors of outcome. CONCLUSIONS The greater the obesity level, the more that IR contributes to the association between obesity and an elevated ALT activity.

Hepatocellular carcinoma (HCC) screening has been recommended for hepatitis B virus (HBV)-infected individuals in an effort to detect HCC at a sufficiently early stage to provide potentially curative treatments. The study reported here is the first to address the rate of HCC screening use in an HBV endemic area.Data were collected from 11,147 adults aged ≥40 years who participated in the 2007-2009 Korea National Health and Nutrition Examination Survey and had a valid HBV surface antigen test. Current HCC screening was defined as either receiving an ultrasonography or an α-fetoprotein measurement in the past year. Prevalence estimates were weighted.The response rate was 78.4 %, and 436 cases of HBV infection were identified. The overall seroprevalence of the HBV surface antigen was 4.1 % [95 % confidence interval (CI) 3.9-4.4 %]. Of the 436 HBV-infected subjects, only 23.2 % (95 % CI 19.5 -27.4 %) were aware that they had been infected, and approximately 27 % (27.1 %; 95 %CI 23.2-to 31.5 %) were up to date with their HCC screening tests; more than half (52.9 %, 95 % CI 48.2-57.5) had never been screened. In a multivariate analysis that included various sociodemographic variables, only self-reported awareness of HBV infection was significantly associated with current HCC screening tests (odds ratio 2.82; 95 % CI 1.64-4.84).Adoption of HCC screening as a standard practice among HBV-infected Korean adults aged ≥40 years is suboptimal. Evidence-based programs in communities and education for both healthcare providers and HBV-infected persons are needed to improve the implementation of HCC screening in clinical practice.

Background/Aim: Alcohol consumption continues to be a common cause of acute and chronic liver disease. Methods: Data from a representative sample of 7,893 adults in the Korean National Health and Nutrition Examination Survey 2009 were analyzed. Alcoholic liver disease (ALD) was defined through heavy alcohol consumption (≥40 g/day for men or ≥20 g/day for women) and through elevated liver tests. Results: Approximately 6.7% (95% confidence interval [CI], 6.0–7.4) was at heavy alcohol consumption. Of these “heavy alcohol consumers,” one quarter also had ALD. The prevalence of ALD was 1.7% (95% CI, 1.3–2.1). Conclusion: ALD is still a burden in the Korean population.

Objectives Whether new biomarkers contribute significantly to the existing, simple noninvasive test (comprising of routine laboratory parameters such as the AST to platelet ratio index (APRI)) for predicting liver fibrosis remains unknown. Methods We measured 7 biomarkers in 91 patients with chronic hepatitis C (CHC): haptoglobin, apolipoprotein A1, α2-macroglobulin, hyaluronic acid, type III procollagenic peptide, matrix metalloproteinase-2, and tissue inhibitor of metalloproteinase-1. Results The “multibiomarker” score (based on regression coefficients of significant biomarkers) is an independent predictive factor for significant fibrosis [APRI-adjusted odds ratio, 2.41 (95% CI, 1.28 to 4.55)]. However, the incorporation of the multibiomarker score into the APRI resulted in only a small diagnostic improvement [0.83 (95% CI, 0.74 to 0.92) vs. 0.79 (0.69 to 0.89); p = 0.19]. Conclusions For assessing significant fibrosis in individual CHC patients, the 7 contemporary biomarkers that we studied add only modestly to the readily available, simple noninvasive index.