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Background: Since 2015, an estimated 415 million people had diabetes worldwide. Although, there is no scientific research related to the effectiveness of chemical substance (brazilin) in Caesalpinia sappan L. that can decrease blood glucose level in humans, many people in Sulawesi consume this wood for diabetes treatment. This study aimed to prove the effect of sappan wood extract on decreasing blood glucose levels in mice and to identify the most effective dose. Methods: Experimental research (pretest and posttest randomized controlled group design) was conducted on 20 male albino mice [body weight (bw): 20–30 g] used as alloxan-induced diabetic models and were divided into four treatment groups according to alloxan dose: control and 0.25, 0.50, and 0.75 g/kg bw (n = 5 for all groups) groups. Results: Significant effects of sappan wood extract on decreasing blood glucose levels in mice were noted in the pretest and posttest (p values are 0.754 and 0.901 respectively). Conclusions: Sappan wood extract could reduce blood glucose levels in mice with diabetes induced by alloxan at 0.25, 0.50, and 0.75 g/kg bw. The extract with 0.50 g/kg bw dose was the most effective in decreasing glucose levels in hyperglycemic mice.

Diffuse correlation spectroscopy (DCS) is an optical technique widely used to monitor blood flow. Recently, efforts have been made to derive new signal processing methods to minimize the systems used and shorten the signal processing time. Herein, we propose alternative approaches to obtain blood flow information via DCS by numerically integrating the temporal autocorrelation curves.We use the following methods: the inverse of KThe simulation and experimental results confirm that both IK2 and INISg1 are sufficiently relevant to capture the changes in blood flow information. More interestingly, when gOur findings strongly indicate that INISg1 with g

Noncancerous breast tissue and cancerous breast tissue have different elastic properties. In particular, cancerous breast tumors are stiff when compared to the noncancerous surrounding tissue. This difference in elasticity can be used as a means for detection through the method of elastographic tomosynthesis by means of physical modulation. This paper deals with a method to visualize elasticity of soft tissues, particularly breast tissues, via x-ray tomosynthesis. X-ray tomosynthesis is now used to visualize breast tissues with better resolution than the conventional single-shot mammography. The advantage of X-ray tomosynthesis over X-ray CT is that fewer projections are needed than CT to perform the reconstruction, thus radiation exposure and cost are both reduced. Two phantoms were used for the testing of this method, a physical phantom and an in silico phantom. The standard root mean square error in the tomosynthesis for the physical phantom was 2.093 and the error in the in silico phantom was negligible. The elastographs were created through the use of displacement and strain graphing. A Gaussian Mixture Model with an expectation–maximization clustering algorithm was applied in three dimensions with an error of 16.667%. The results of this paper have been substantial when using phantom data. There are no equivalent comparisons yet in 3D x-ray elastographic tomosynthesis. Tomosynthesis with and without physical modulation in the 3D elastograph can identify feature groupings used for biopsy. The studies have potential to be applied to human test data used as a guide for biopsy to improve accuracy of diagnosis results. Further research on this topic could prove to yield new techniques for human patient diagnosis purposes., This paper tests a method to visualize elasticity of soft tissues, particularly breast tissues, via x-ray tomosynthesis. Testing with a physical phantom and an in silico phantom found the standard root mean square error in the tomosynthesis for the physical phantom was 2.093 and the error in the in silico phantom was negligible. Tomosynthesis with and without physical modulation in the 3D elastograph can identify feature groupings used for biopsy. These studies show the potential of human test data to be used as a guide for biopsy to improve accuracy of diagnosis.

Background The Helicobacter pylori eradication rate has decreased with increasing antibiotic resistance. We conducted a prospective, nationwide, multicenter registry study to monitor the real status of H. pylori eradication therapy and to investigate the association between eradication success and antibiotic use density in Korea. Materials and Methods We enrolled 9318 patients undergoing H. pylori eradication therapy from 37 hospitals through “on‐line database registry” from October 2010 to July 2015. Demographic data, detection methods, treatment indications, regimens, durations, compliance, adverse events, and eradication results were collected. The use of all commercially available eradication antibiotics was analyzed through the Korean National Health Insurance data of the Health Insurance Review and Assessment Service. The defined daily dose of antibiotics was used to standardize drug use comparisons. Results Finally, 6738 patients were analyzed. The overall eradication rate of first‐line therapy was 71.8%. The eradication success rates were 71.7%, 86.9%, and 74.0% for standard triple therapy for 7 days, quadruple therapy, and concomitant therapy, respectively. The eradication success rate in naive patients was higher than that in those who previously underwent H. pylori eradication. Eradication success was significantly associated with younger age, female sex, and high compliance. Regional differences in eradication rates were observed. The yearly use density of clarithromycin increased statistically in seven regions across the country from 2010 to 2015. The yearly use density of amoxicillin in the Gyeongsang and Chungcheong areas was significantly increased (P

Mori Cortex Radicis (MCR) is a well-known Korean and Chinese folk medicine with anti-obesity, anti-inflammatory, anti-asthmatic, and hypoglycemic activities. This study was aimed to evaluate the total phenolic and flavonoid contents, as well as intracellular antioxidant and anti-inflammatory effects of water and 70% (v/v) ethanol extracts of MCR. The antioxidant activities of MCR extracts were determined with diphenyl-2-picrylhydrazyl and 2,2′-azinobis[3-ethylbenzothiazoline-6-sulfonic] scavenging activity assays. The suppressive activities of MCR extracts on the production of nitric oxide (NO*) and the expression of cytokines, c-Fos, activated p38-Mitogen-activated protein kinase (MAPK), and Nuclear factor Kappa B (NF-κB) and splenocytes proliferation in lipopolysaccharide-treated macrophages were determined. Furthermore, this study demonstrated the effects of MCR on reactive oxygen species production in murine macrophages. Mori Cortex Radicis restored deoxyribonucleic acid damages at higher concentrations of the extracts and significantly suppressed free radicals and NO* production. In this study, MCR significantly restored inflammatory responses and intracellular antioxidant activities in murine macrophages (RAW 264.7), which anticipated that MCR could be used as a natural anti-inflammatory agent.

Although gastric cancer is quite common in Korea, the treatment outcome is relatively favorable compared to those in western countries. However, there are currently no Korean multidisciplinary guidelines for gastric cancer. Experts from related societies developed guidelines de novo to meet Korean circumstances and requirements, including 23 recommendation statements for diagnosis (n=9) and treatment (n=14) based on relevant key questions. The quality of the evidence was rated according to the GRADE evidence evaluation framework: the evidence levels were based on a systematic review of the literature, and the recommendation grades were classified as either strong or weak. The applicability of the guidelines was considered to meet patients' view and preferences in the context of Korea. The topics of the guidelines cover diagnostic modalities (endoscopy, endoscopic ultrasound, and radiologic diagnosis), treatment modalities (surgery, therapeutic endoscopy, chemotherapy, and radiotherapy), and pathologic evaluation. An external review of the guidelines was conducted during the finalization phase.

In tissue elasticity imaging, measuring the strain tensor components is necessary to solve the inverse problem. How- ever, itis impractical to measure all the tensor components in ultrasound or MRI elastography because of their anisotropic spatial resolution. The objective of this study is to compute 3D strain tensor maps from the 3D CT images of a tissue-mimicking phan- tom. We took 3D micro-CT images of the phantom twice with applying two different mechanical compressions to it. Applying the 3D image correlation technique to the CT images under different compression, we computed 3D displacement vectors and strain tensors at every pixel. To evaluate the accuracy of the strain tensor maps, we made a 3D FEM model of the phantom, and we computed strain tensor maps through FEM simulation. Experimentally obtained strain tensor maps showed similar patterns to the FEM-simulated ones in visual inspection. The correlation between the strain tensor maps obtained from the experiment and the FEM simulation ranges from 0.03 to 0.93. Even though the strain tensor maps suffer from high level noise, we expect the x-ray strain tensor imaging may find some biomedical applications such as malignant tissue characterization and stress analysis inside the tissues.

Background/Aims A worldwide increase in amoxicillin resistance in Helicobacter pylori is having an adverse effect on eradication therapy. In this study, we investigated the mechanism of the amoxicillin resistance of H. pylori in terms of amino acid substitutions in penicillin-binding protein 1 (PBP1). Methods In total, 150 H. pylori strains were isolated from 144 patients with chronic gastritis, peptic ulcers, or stomach cancer. The minimum inhibitory concentrations (MICs) of the strains were determined with a serial 2-fold agar dilution method. The resistance breakpoint for amoxicillin was defined as >0.5 µg/mL. Results Nine of 150 H. pylori strains showed amoxicillin resistance (6%). The MIC values of the resistant strains ranged from 1 to 4 µg/mL. A PBP1 sequence analysis of the resistant strains revealed multiple amino acid substitutions: Val16→Ile, Val45→Ile, Ser414→Arg, Asn562→Tyr, Thr593→Ala, Gly595→Ser, and Ala599→Thr. The natural transformation of these mutated genes into amoxicillin-sensitive strains was performed in two separate pbp1 gene segments. A moderate increase in the amoxicillin MIC was observed in the segment that contained the penicillin-binding motif of the C-terminal portion, the transpeptidase domain. Conclusions pbp1 mutation affects the amoxicillin resistance of H. pylori through the transfer of the penicillin-binding motif.

Radical gastrectomy followed by adjuvant chemotherapy for advanced gastric cancer causes serious nutritional impairment. Our study evaluated the clinical impact of body mass index (BMI) on the long-term outcomes of advanced gastric cancer (stage II and III). We analyzed 211 cases of stage II and III gastric cancer between January 2005 and December 2010 at Chung-Ang University Hospital, Seoul, Korea. Patients were divided into four groups according to BMI: underweight, normal, overweight, and obese. In addition, we divided patients into two groups: BMI-High (BMI ≥ 23 kg/m2) vs. BMI-Low (BMI < 23 kg/m2). We assessed age, sex, tumor location, lymph node (LN) involvement, operation method, initial cancer stage, recurrence, and survival between the two groups. There was significant difference in overall survival (OS) between the underweight group and the other groups (P = 0.005). The survival of the BMI-High group was better than that of the BMI-Low group. The rate of cancer-related death in the BMI-Hi...

Purpose: Elastography is a medical imaging modality to visualize the elasticity of soft tissues.Ultrasound and MRI have been exclusively used for elastography of soft tissues since they can sensitize the tissues’ minute displacements of an order ofμm. It is known that ultrasound and MRI elastography show cancerous tissues with much higher contrast than conventional ultrasound and MRI. To evaluate possibility of combining elastography with x-ray imaging, we have calculated strain images of a breast-mimicking phantom from its 3D CTimage data. Methods: We first simulated the x-rayelastography using a FEM model which incorporated both the elasticity and x-ray attenuation behaviors of breast tissues. After validating the x-rayelastography scheme by simulation, we made a breast-mimicking phantom that contained a hard inclusion against soft background. With a micro-CT, we took 3D images of the phantom twice, changing the compressing force to the phantom. From the two 3D phantom images taken with two different compression ratios, we calculated the displacement vector maps that represented the compression-induced pixel displacements. In calculating the displacement vectors, we tracked the movements of image feature patterns from the less-compressed-phantom images to the more-compressed-phantom images using the 3D image correlation technique. We obtained strain images of the phantom by differentiating the displacement vector maps. Results: The FEM simulation has shown that x-ray strain imaging is possible by tracking image feature patterns in the 3D CTimages of the breast-mimicking phantom. The experimental displacement and strain images of a breast-mimicking phantom, obtained from the 3D micro-CT images taken with 0%–3% compression ratios, show behaviors similar to the FEM simulation results. The contrast and noise performance of the strain images improves as the phantom compression ratio increases. Conclusions: We have experimentally shown that we can improve x-ray strain image quality by applying 3D image correlation to the two sets of 3D CTimages taken with different compression ratios. But, we need further investigations to evaluate the strain imaging performance considering the noise and decorrelation effects as well as the extra dose caused by two scans.

Ketamine, which is a general anaesthetic that induces a dissociative anaesthesia, acts by blocking the N-methyl-D-aspartate receptor (NMDAr) in the brain. Although ketamine elevates blood pressure under the clinical setting, the in-vitro effect of ketamine is vasodilatory. However, it is not clear yet whether the vasodilation by ketamine involves functions of the NMDAr. Therefore, we examined whether the NMDAr is functional in vascular smooth muscle and whether the vasodilatory effect of ketamine is associated with the NMDAr.We measured isometric tension of endothelium-denuded arterial rings from rat mesentery. The relaxing effects of ketamine, after rings were precontracted with noradrenaline (10 mumol l) or high KCl (70 mmol l), were examined. The effects of DL-2-amino-5-phosphonopentanoic acid (AP-5), a competitive NMDAr blocker that is structurally distinct from ketamine, were also examined. The relaxing effects of ketamine in the presence of AP-5 were compared with those in the absence of AP-5. The effects of NMDAr agonists N-methyl-D-aspartate and glutamate were analysed in order to examine the existence of a functional NMDAr.Both S(+)-ketamine and racemic(+/-)-ketamine, with similar potencies and efficacies and in a concentration-dependent manner, relaxed the precontracted arterial rings. However, AP-5 neither relaxed the arteries nor affected the vasodilatory actions of ketamine. N-methyl-D-aspartate and glutamate (0.01-1 mmol l) had negligible effects on isometric tension under the resting or precontracted condition.These results suggest that the NMDAr is not functional in vascular smooth muscle, and the vasodilatory action of ketamine is independent of the NMDAr in the rat mesenteric artery.

Background and Aim: Gastric cancer is a major health burden in the Asia–Pacific region but consensus on prevention strategies has been lacking. We aimed to critically evaluate strategies for preventing gastric cancer. Methods: A multidisciplinary group developed consensus statements using a Delphi approach. Relevant data were presented, and the quality of evidence, strength of recommendation, and level of consensus were graded. Results: Helicobacter pylori infection is a necessary but not sufficient causal factor for non-cardia gastric adenocarcinoma. A high intake of salt is strongly associated with gastric cancer. Fresh fruits and vegetables are protective but the use of vitamins and other dietary supplements does not prevent gastric cancer. Host–bacterial interaction in H. pylori infection results in different patterns of gastritis and differences in gastric acid secretion which determine disease outcome. A positive family history of gastric cancer is an important risk factor. Low serum pepsinogens reflect gastric atrophy and may be useful as a marker to identify populations at high risk for gastric cancer. H. pylori screening and treatment is a recommended gastric cancer risk reduction strategy in high-risk populations. H. pylori screening and treatment is most effective before atrophic gastritis has developed. It does not exclude the existing practice of gastric cancer surveillance in high-risk populations. In populations at low risk for gastric cancer, H. pylori screening is not recommended. First-line treatment of H. pylori infection should be in accordance with national treatment guidelines. Conclusion: A strategy of H. pylori screening and eradication in high-risk populations will probably reduce gastric cancer incidence, and based on current evidence is recommended by consensus.

Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Department of Medicine, Chung-Ang University College of Medicine, Seoul1, Department of Internal Medicine, Ewha Medical Research Institute, Ewha Womans University School of Medicine, Seoul2, Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul3, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul4, Department of Nuclear Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul5, Department of Pathology, Inha University School of Medicine, Incheon6, Department of Surgery, Ewha Womans University School of Medicine, Seoul7, Center for Gastric Cancer, National Cancer Center, Goyang8, Department of Surgery, Seoul National University Hospital, Seoul9, Department of Surgery, Yonsei University College of Medicine, Seoul10, Department of Internal Medicine, Asan Medical Center, Ulsan University College of Medicine, Seoul11, Department of Internal Medicine, Korea University College of Medicine, Seoul12, Department of Internal Medicine, Hallym University Medical Center, Hallym University College of Medicine, Anyang13, Department of Medical Oncology, Yonsei University College of Medicine, Seoul14, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul15, Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul16, Department of Pathology, Seoul St. Mary`s Hospital, The Catholic University of Korea, Seoul17, Department of Preventive Medicine, Korea University Medical College, Seoul18, Korea Although, gastric cancer is quite common in Korea, the treatment outcome is relatively favorable compared to that of Western countries. However, there is no Korean multidisciplinary guideline for gastric cancer and thus, a guideline adequate for domestic circumstances is required. Experts from related societies developed 22 recommendation statements for the diagnosis (n=9) and treatment (n=13) based on relevant key questions. Evidence levels based on systematic review of literatures were classified as five levels from A to E, and recommendation grades were classified as either strong or weak. The topics of this guideline cover diagnostic modalities (endoscopy, endoscopic ultrasound, radiologic diagnosis), treatment modalities (surgery, therapeutic endoscopy, chemotherapy, radiotherapy) and pathologic evaluation. External review of the guideline was conducted at the finalization phase. (Korean J Gastroenterol 2014;63:66-81)

This paper presents a formalism-based methodology and its implemented environment which constitutes a sound framework for real-time systems development. The software and/or hardware systems developed in such a formal manner are wellstructured and maintainable. We first propose a set-theoretic VSSS (Variable Structure System Specification) formalism. This formalism is the core of the presented methodology which supports a means of formal specification for real-time systems. We then develop the environment, including VSSS language definition, a translator for the language, and supporting libraries for real-time execution. Finally, a demonstration of the methodology in development of a real-time event manager, a subsystem of an ATM-based communication system, shows the correctness and efficiency of the methodology.

Scan time of spectral-CTs is much longer than conventional CTs due to limited number of x-ray photons detectable by photon-counting detectors. However, the spectral pixel information in spectral-CT has much richer information on physiological and pathological status of the tissues than the CT-number in conventional CT, which makes the spectral- CT one of the promising future imaging modalities. One simple way to reduce the scan time in spectral-CT imaging is to reduce the number of views in the acquisition of projection data. But, this may result in poorer SNR and strong streak artifacts which can severely compromise the image quality. In this work, spectral-CT projection data were obtained from a lab-built spectral-CT consisting of a single CdTe photon counting detector, a micro-focus x-ray tube and scan mechanics. For the image reconstruction, we used two iterative image reconstruction methods, the simultaneous iterative reconstruction technique (SIRT) and the total variation minimization based on conjugate gradient method (CG-TV), along with the filtered back-projection (FBP) to compare the image quality. From the imaging of the iodine containing phantoms, we have observed that SIRT and CG-TV are superior to the FBP method in terms of SNR and streak artifacts.

Background Despite its superb lateral resolution, flat-panel-detector (FPD) based tomosynthesis suffers from low contrast and inter-plane artifacts caused by incomplete cancellation of the projection components stemming from outside the focal plane. The incomplete cancellation of the projection components, mostly due to the limited scan angle in the conventional tomosynthesis scan geometry, often makes the image contrast too low to differentiate the malignant tissues from the background tissues with confidence. Methods In this paper, we propose a new method to suppress the inter-plane artifacts in FPD-based tomosynthesis. If 3D whole volume CT images are available before the tomosynthesis scan, the CT image data can be incorporated into the tomosynthesis image reconstruction to suppress the inter-plane artifacts, hence, improving the image contrast. In the proposed technique, the projection components stemming from outside the region-of-interest (ROI) are subtracted from the measured tomosynthesis projection data to suppress the inter-plane artifacts. The projection components stemming from outside the ROI are calculated from the 3D whole volume CT images which usually have lower lateral resolution than the tomosynthesis images. The tomosynthesis images are reconstructed from the subtracted projection data which account for the x-ray attenuation through the ROI. After verifying the proposed method by simulation, we have performed both CT scan and tomosynthesis scan on a phantom and a sacrificed rat using a FPD-based micro-CT. Results We have measured contrast-to-noise ratio (CNR) from the tomosynthesis images which is an indicator of the residual inter-plane artifacts on the focal-plane image. In both cases of the simulation and experimental imaging studies of the contrast evaluating phantom, CNRs have been significantly improved by the proposed method. In the rat imaging also, we have observed better visual contrast from the tomosynthesis images reconstructed by the proposed method. Conclusions The proposed tomosynthesis technique can improve image contrast with aids of 3D whole volume CT images. Even though local tomosynthesis needs extra 3D CT scanning, it may find clinical applications in special situations in which extra 3D CT scan is already available or allowed.

Background Ring artifacts are the concentric rings superimposed on the tomographic images often caused by the defective and insufficient calibrated detector elements as well as by the damaged scintillator crystals of the flat panel detector. It may be also generated by objects attenuating X-rays very differently in different projection direction. Ring artifact reduction techniques so far reported in the literature can be broadly classified into two groups. One category of the approaches is based on the sinogram processing also known as the pre-processing techniques and the other category of techniques perform processing on the 2-D reconstructed images, recognized as the post-processing techniques in the literature. The strength and weakness of these categories of approaches are yet to be explored from a common platform. Method In this paper, a comparative study of the two categories of ring artifact reduction techniques basically designed for the multi-slice CT instruments is presented from a common platform. For comparison, two representative algorithms from each of the two categories are selected from the published literature. A very recently reported state-of-the-art sinogram domain ring artifact correction method that classifies the ring artifacts according to their strength and then corrects the artifacts using class adaptive correction schemes is also included in this comparative study. The first sinogram domain correction method uses a wavelet based technique to detect the corrupted pixels and then using a simple linear interpolation technique estimates the responses of the bad pixels. The second sinogram based correction method performs all the filtering operations in the transform domain, i.e., in the wavelet and Fourier domain. On the other hand, the two post-processing based correction techniques actually operate on the polar transform domain of the reconstructed CT images. The first method extracts the ring artifact template vector using a homogeneity test and then corrects the CT images by subtracting the artifact template vector from the uncorrected images. The second post-processing based correction technique performs median and mean filtering on the reconstructed images to produce the corrected images. Results The performances of the comparing algorithms have been tested by using both quantitative and perceptual measures. For quantitative analysis, two different numerical performance indices are chosen. On the other hand, different types of artifact patterns, e.g., single/band ring, artifacts from defective and mis-calibrated detector elements, rings in highly structural object and also in hard object, rings from different flat-panel detectors are analyzed to perceptually investigate the strength and weakness of the five methods. An investigation has been also carried out to compare the efficacy of these algorithms in correcting the volume images from a cone beam CT with the parameters determined from one particular slice. Finally, the capability of each correction technique in retaining the image information (e.g., small object at the iso-center) accurately in the corrected CT image has been also tested. Conclusions The results show that the performances of the algorithms are limited and none is fully suitable for correcting different types of ring artifacts without introducing processing distortion to the image structure. To achieve the diagnostic quality of the corrected slices a combination of the two approaches (sinogram- and post-processing) can be used. Also the comparing methods are not suitable for correcting the volume images from a cone beam flat-panel detector based CT.

For the second year of this project, we continued to monitor the changes in endogenous tissue chromophores such as oxy-, deoxy-, total hemoglobin concentration, tissue oxygen saturation, lipid and water contents during tumor growth and chemotherapy using a diffuse optical imaging system. From clinical study, we found that responding tumors show oxyhemoglobin flare within 1 week post neoadjuvant chemotherapy. To confirm this, we monitored the changes of endogenous chromophores post chemotherapy and compared those with controls. We found that functional changes such as oxy-, deoxyhemoglobin, and water precedes the change in tumor volume. This proved our hypothesis that functional changes should occur prior to physical changes when tumors respond to therapy. We have also administered vascular disrupting agents and monitored the changes in tumor oxygenation and blood volume and compared those with contralateral normal breast tissues. We found that vascular disrupting agents work mainly on tumors and also they are more effective in large tumors than small tumors. We also employed Raman spectroscopic measurements on normal tissues near tumor cell inoculation and observed the Raman signal changes as tumor grows.

Eradication of Helicobacter pylori using first-line therapy is becoming less effective. Subjects who had been treated for H. pylori infection were prospectively enrolled through an on-line database registry from October 2010 to December 2012. Demographic data, detection methods, treatment indication, regimens, durations, compliance, adverse events, and eradication results for H. pylori infection were collected. Data of 3,700 patients from 34 hospitals were analyzed. The overall eradication rate of the first-line therapy was 73.0%. Eradication failure was significantly associated with old age, concomitant medication, and comorbidity. Regional differences in eradication rates were observed. The most common first-line therapy was proton pump inhibitor-based triple therapy (standard triple therapy, STT) for 7 days (86.8%). The eradication rates varied with regimens, being 73% in STT, 81.8% in bismuth-based quadruple therapy, 100% in sequential therapy, and 90.3% in concomitant therapy. The eradication rate in treatment-naïve patients was higher than that in patients previously treated for H. pylori infection (73.8% vs. 58.5%, P < 0.001). The overall eradication rate for second-line therapy was 84.3%. There was no statistical difference in eradication rates among various regimens. H. pylori eradication rate using STT is decreasing in Korea and has become sub-optimal, suggesting the need for alternative regimens to improve the efficacy of first-line therapy for H. pylori infection.

Laser direct writing (LDW) process is developed using 3-rd harmonic Diode Pumped Solid State Laser (DPSSL) with the near UV wavelength of 355 nm. Photo-sensitive curable polymer is irradiated by UV laser and developed using polymer solvent to obtain quasi-3D patterns. We performed basic experiments for the various process conditions such as laser power, writing speed, laser focus, and optical polymer property to get the optimal conditions. This process could be applied to fabricate a single-mode waveguide without expensive mask projection method. Experimentally, the patterns of trapezoidal shape were manufactured into dimension of 8.4μm width and 7.5μm height. Propagation loss of planar waveguide was 1.42 dB/cm at wavelength of 1,550 nm.

The clinical value of second-look endoscopy (SLE) after endoscopic submucosal dissection (ESD) has been doubted continuously. The aim of this study was to assess the effectiveness of SLE based on the risk of delayed bleeding after ESD.A total of 310 lesions of gastric epithelial neoplasms treated by ESD were reviewed. The lesions were divided into two groups based on the risk of post-procedural bleeding estimated by Forrest classification. The high risk of rebleeding group (Forrest Ia, Ib and IIa) required endoscopic treatment, while the low risk of rebleeding group (Forrest IIb, IIc and III) did not. Delayed bleeding after ESD was investigated.Sixty-six lesions were included in the high risk of rebleeding group and 244 lesions in the low risk of rebleeding group. There were no significant differences in delayed bleeding between the high risk group (1/66) and the low risk group (1/244) (P = 0.38). The high risk of rebleeding group tended to be located more often in the mid-third and had higher appearance of flat or depressed shape than the low risk group (P = 0.004 and P = 0.006, respectively).SLE with pre-emptive prophylactic endoscopic treatment is still effective in preventing delayed bleeding after ESD.

lower 65 (30.1%); Period II: upper 37 (20.0%), middle 85 (45.9%), lower 61 (33.0%), Period III: upper 35 (22.2%), middle (40.5%), lower 55 (35.9%). Pathological examination revealed as follows (differentiated type/ undifferentiated/ others/ unknown); Period I: 132/ 69/0/17; Period II: 123/54/2/6; Period III: 103/43/2/0. These data indicated the locations and pathological features of the stomach cancer in this survey were not changed in recent 10 years. Regarding therapeutic approach to gastric cancer, open laparotomy was mainly applied to the gastric cancer in period I (2002-2004) as 159 out of 216 (73.6%) patients. Endoscopic treatment was performed in 38 patients (17.6%), whereas only 4 patients (1.9%) were treated under laparoscopy. In Period II (2005-2007), the ratio endoscopic treatment increased significantly (24.3%, 45/153). The ratio of laparoscopic surgery increased form 1.9% to 13.0% (24/153), although the number of gastric cancer patients treated by open laparotomy was decreased (58.9% 109/185). In Period III, the ratio of laparoscopic surgery (32.0% 49/153) was markedly increased compared to Periods I & II, while increase in the ratio of endoscopic treatment was limited (52/153 34.0%). because application of endoscopic treatment was limited to the gastric cancer within themucosa. This study clearly demonstrated therapeutic approach to the gastric cancer was replaced open laparotomy with endoscopic treatment and laparoscopic surgery in recent 10 years, although backgrounds of the gastric cancer were not changed.

(range 2-210). Group A was significantly younger than group B (59.9±17.4 vs 67.7±15.6, p

Gastric and Duodenal Pathology in Patients With Reflux Esophagitis: Case-Control Study Sung Woo Jung*, Sang Woo Lee, IL Kwun Chung, Jun Haeng Lee, Hwoon-Yong Jung, Jeong Seop Moon, Jin IL Kim, Jae G. Kim, Yong Chan Lee, Dong Ho Lee, Hak Yang Kim, Sang Young Seol Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea; Internal Medicine, Soonchunhyang University, Cheonan Hospital, Cheonan, Republic of Korea; Internal Medicine, Samsung Medical center, Seoul, Republic of Korea; Internal Medicine, University of Ulsan, Asan Medical Center, Seoul, Republic of Korea; Internal Medicine, Seoul Paik Hospital, Seoul, Republic of Korea; Internal Medicine, St. Mary’s Hospital, Seoul, Republic of Korea; Internal Medicine, Chung-Ang University College of Medicine, Seoul, Republic of Korea; Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea; Internal Medicine, Seoul National University Bundang Hospital, Seoul, Republic of Korea; Internal Medicine, Kangdong Sacred Heart Hospital, Seoul, Republic of Korea; Internal Medicine, In-Je University Medical College, Busan, Republic of Korea Background: Gastroduodenal diseases may affect gastroesophageal reflux desease (GERD) by altering gastric acid secretion or mucosal inflammation. Several studies reported that GERD was associated with peptic ulcer disease or gastric inflammation, but inversely related to atrophic gastritis or Helicobacter pylori infection. Thus, we aimed to investigate the prevalence of gastroduodenal diseases in the patients with reflux esophagitis (RE) and the association between gastroduodenal diseases and RE. Methods: From September 2009 through February 2010, a total of 1,156 patients with RE diagnosed by endoscopy, were consecutively enrolled in this multicenter study. The control population comprised 2,329 patients without RE who underwent endoscopy during the same period. Endoscopic findings and medical history were assessed. Results: Mean age was 52.53 13.94 in RE group and 51.08 13.66 in control group (p 0.003). Male gender was more prevalent in RE group than control group (71.5% vs. 42.6%) (p 0.001). Univariate analysis showed that atrophic gastritis was less common in GERD group (39.8%) than control group (45.5%) (p 0.001). Erosive gastritis and duodenitis were more common in GERD group (38.2% and 6.1%) than control group (32.6% and 2.8%) (p 0.001). Duodenal ulcer was more frequently found in GERD group (11.1% vs. 8.0%) (p 0.003) but the prevalence of gastric ulcer was not different between the two groups (11.9% vs. 10.0%) (p 0.096). H. pylori infections was tested in 1,300 patients and the infection rate of H. pylori was higher in control group (43.5% vs. 28.3%) (p 0.003). Gastric tumor incidence showed no difference between the two groups (4.3% vs. 5.2%, p 0.263). The age and sex-adjusted analysis identified following: atrophic gastritis (OR 0.70, CI: 0.60-0.82), erosive gastritis (OR 1.24, CI: 1.06-1.44), gastric ulcer (OR 0.98, CI: 0.77-1.25), duodenal ulcer (OR 1.15, CI: 0.90-1.47), duodenitis (OR 1.80,CI: 1.26-2.58) gastric tumor (OR 0.79, CI: 0.56-1.14) and H. pylori infection (OR 0.48, CI: 0.37-0.62). Conclusion: RE is positively associated with erosive gastritis and duodenitis, but negatively related to atrophic gastritis and H. pylori infection. Gastroduodenal inflammation should be considered in the management of RE.

29 Background: Gastric cancer is a major cause of death and a substantial socioeconomic burden in Korea. The National Cancer Screening Program for Medicaid recipients was initiated in 1999 and has contributed to reduction of cancer-related mortality in Korea. Endoscopy may be cost-effective screening tool in Korea, where the cost of endoscopy and UGIS are similar and the incidence of gastric cancer is high. Most of Japanese studies on the efficiency of mass screening for gastric cancer have dealt with photoflurography as a screening tool. Although biennial gastric cancer screening by endoscopy has been increasing in Korea as part of the National Cancer Screening Program, few studies have evaluated its efficiency. Therefore, we analyzed the outcomes and efficiency of the National Gastric Cancer Screening Program using endoscopy in Korea. Methods: We reviewed medical records from the National Gastric Cancer Screening Program at Chung-Ang University hospital in Korea from January 2007 to December 2010. The study population was comprised of Medicaid recipients ≥ 40 years of age who were taken from the National Health Insurance Corporation. Results: A total of 41,150 asymptomatic subjects underwent endoscopy for gastric cancer screening. The mean age of the screened subjects was 56.3 years for men and 48.9 years for women. The male to female ratio of the screened subjects was 1.57:1. Gastric cancer was diagnosed in 102 (0.24%) of 41,150 subjects (60 men and 42 women). Their mean age was 54.4 years. Of these, 76 subjects (0.18%) were diagnosed as early gastric cancer and 26 subjects (0.06%) as advanced gastric cancer. The proportion of early gastric cancer among total gastric cancers was 74.5%. During the period, only 6,586 (16.0%) subjects participated in the biennial gastric cancer screening (59% for men and 49% for women). Conclusions: Despite accomplishments of the National Gastric Cancer Screening Program in Korea, low compliance to the screening program remains an issue. Furthermore, its cost-effectiveness analysis will be needed for successful progression.

Helicobacter pylori (H. pylori) causes chronic gastritis, peptic ulcer disease, primary B-cell gastric lymphoma, and adenocarcinoma of the stomach. The eradication of H. pylori infection requires combination of antibiotics including proton pump inhibitors. However, development of antibiotic resistance is a major cause of treatment failure. To select an appropriate regimen, systemic information on the antibiotic resistance is mandatory. H. pylori acquires resistance essentially via point mutations, and this phenomenon is found with most antibacterials. The prevalence of primary antibiotic resistance in H. pylori strains isolated from Korean patients has been increasing along with the shift to high minimum inhibitory concentrations from 1987 to 2009. Moreover, MIC values of secondary isolates were higher than those of primary isolates. In addition, there is an increasing tendency for the emergence of strains with multi-drug resistance. Resistance rates of H. pylori to amoxicillin, clarithromycin, metronidazole, tetracycline, ciprofloxacin, levofloxacin, and moxifloxacin have been reported up to 18.5%, 38.5%, 66.2%, 34.6%, 34.6%, 29.5%, and 23.2%, respectively. Especially, antibiotic resistance to metronidazole or clarithromycin affects undermining the efficacy of eradication treatment. Further nation-wide surveillance regarding the effect of antibiotic resistance on the eradication rate is necessary to establish the appropriate treatment for H. pylori infection. (The Korean Journal of Helicobacter and Upper Gastrointestinal Research 2011;11:13-20) Key Word: Helicobacter pylori 중앙대학교 의과대학 내과학교실

Prevalence of erosive esophagitis (EE) has been increasing in Korea. The purpose of this study was to estimate prevalence of EE among low socioeconomic population in Korea and to investigate risk factors for EE. We reviewed the medical records of 7,278 subjects who were examined by upper endoscopy in the Korean National Cancer Screening Program at Chung-Ang University Yong-san Hospital from March 2003 to March 2008. The study population included subjects ≥ 40 yr of age who were Medicaid recipients and beneficiaries in the National Health Insurance Corporation. Multivariate analysis was used to determine risk factors for EE. Prevalence of EE was 6.7% (486/7,278). According to the LA classification system, LA-A in 344 subjects, LA-B in 135 subjects, and LA-C and D in 7 subjects. In multivariate analysis, age ≥ 60 yr, male sex, BMI ≥ 25, current smoking, alcohol consumption, fasting glucose level ≥ 126 mg/dL, and endoscopic hiatal hernia were significant risk factors for EE. The prevalence of EE in low socioeconomic Korean population is similar to that in personal annual medical check-ups. Risk factors for EE among them include old age, male sex, BMI ≥ 25, current smoking, alcohol consumption, fasting glucose level ≥ 126 mg/dL, and hiatal hernia.

phospholipids, higher CSI, lower nucleation time and higher concentration of deoxicholic acid when compared with control group. Conclusions: Our results showed the composition of gallstones is similar to developed country in according with the recent improvement of social condition of our country and with literature findings. Lithogenic factors were presented in the bile of patients with cholesterol gallstones and correlate with the presence of predictor's factors for the gallstone formation in our population.

BACKGROUND/AIM Nucleotide binding oligomerization domain (Nod) proteins are members of a family that includes the apoptosis regulator APAF1. Nod proteins have been implicated in the induction of NF-κB activity and in the activation of caspases. Helicobacter pylori (H. pylori) infection is reported to express TLR 4, TLR-5 and TLR-9 in gastric epithelial cells. However, TLR-4 and TLR-5 are not recognized as important role in H. pylori infection. This implicated that another signal transducer different from TLR pathway may affect NFκB activation in cag PAI (+) H. pylori infection. The purpose of this study was to investigate whether cag PAI (+) H. pylori infection affects NF-κB activation and IL-8 production through Nod1 and to evaluate the transepithelial neutrophil migration induced by H. pylori infection. METHODS Stable transfection of Dominant Negative (DN) Nod1 in AGS cell line was established followed by NF-κB activation and IL-8 production by H. pylori HP 99 infection was assessed. The role of cag PAI was examined comparing wild type H. pylori strain with cag PAI knock-down CagAand CagEH. pylori strain. To assess the production of IL-8, we examined mRNA expression using RT-PCR, and IL-8 secretion using ELISA. To assess the inhibition of NF-κB activation, we examined degradation and phosphorylation of IκBα using western blot and EMSA. To examine the role of cag PAI, we examined the production of IL-8 and the inhibition of NF-κB activation in the cag PAI knock-down CagAand CagEH. pylori infection in the same manner with wild type. We established the neutrophil migration model induced by H. pylori infection in polarized DN Nod1 Caco-2 cell line and evaluated transepithelial neutrophil migration as to the cag PAI status. RESULTS Stable transfection of DN Nod1 followed by cag PAI (+) H. pylori inhibited IL-8 mRNA expression and IL-8 production. In addition, cag PAI (+) H. pylori inhibited IκB-α degradation and IκB-α phosphorylation. IL-8 mRNA expression and IL-8 production by CagA-and CagEH. pylori were significantly decreased compared with those by wild type H. pylori. IκB-α degradation and IκB-α phosphorylation by CagA-and CagEH. pylori were significantly decreased compared with those by wild type H. pylori. NF-κB expression by CagA-and CagEH. pylori was significantly decreased compared with that by wild type H. pylori. Transepithelial neutrophil migration was more prominent in wild type H. pylori than CagAand CagEH. pylori CONCLUSION Signaling through Nod1 plays an essential role in the upregulated expression of IL-8 in human epithelial cells infected with H. pylori.