[Comparison of clinical characteristics and outcomes between geriatric and non-geriatric patients in peptic ulcer bleeding].

Background/aims: In geriatric patients with peptic ulcer, the use of NSAID and prevalence of chronic illness have been increased, but the Helicobacter pylori (H. pylori) infected portion decreased. The aim of this study was to evaluate the clinical characteristics and outcomes of geriatric patients (aged 65 or older) with peptic ulcer bleeding and compare with non-geriatric patients (less than 65 years old).

The prevalence and clinical characteristics of reflux esophagitis in koreans and its possible relation to metabolic syndrome.

The prevalence of reflux esophagitis is increasing in Korea. To estimate the prevalence and clinical characteristics of reflux esophagitis in healthy subjects, we retrospectively examined the medical records of healthy subjects undergoing a routine check-up from October 2004 to September 2005. A total of 6,082 (3,590 men, mean age 44+/-10 yr) subjects were enrolled in this study.

Improvement of accuracy of diffusion MRI using real-time self-gated data acquisition.

Diffusion-weighted and diffusion tensor MR imaging (DWI, DTI) techniques are generally performed with signal averaging of multiple measurements to improve the signal-to-noise ratio (SNR) and the accuracy of the diffusion measurement. Any discrepancy in the images between different averages causes errors which reduce the accuracy of the diffusion MRI measurements. In this report, a motion artifact reduction scheme with a real-time self-gated (RTSG) data acquisition for diffusion MRI using two-dimensional echo planar imaging (2D EPI) is described.

Associations between oxidized LDL to LDL ratio, HDL and vascular calcification in the feet of hemodialysis patients.

Cardiovascular mortality is associated with vascular calcification (VC) in hemodialysis (HD) patients. The present study was designed to find factors related with medial artery calcification on the plain radiography of feet by comparing C-reactive protein (CRP), plasminogen activator inhibitor type 1 (PAI-1) and lipid profile including oxidized low density lipoprotein (ox-LDL) and to elucidate associations among these factors in HD patients. Forty-eight HD patients were recruited for this study.

Poly(oxyethylene)/silver nanoparticle composites as biocidal agents.

We prepared polymeric N-halamine/silver nanoparticle composites to develop new effective biocidal systems. They were synthesized by mixing poly[oxy[(3-chloro-4,4-dimethyl-imidazolelidine-2,5-dionyl)methyl]ethylene](POCE) with silver perchlorate followed by UV reduction. These composites exhibit potent antibacterial activity against the gram-negative bacteria, Escherichia coli.

Size controlled miniscale synthesis of silver nanoparticles using TEM electron beam.

A method for one-pot size-controlled synthesis of silver nanoparticles is proposed and described. The synthesis is based on the reduction of silver-alkanethiolates complexes having highly ordered supramolecular structures through electron beam irradiation in transmission electron microscope (TEM). The method allows synthesis of silver nanoparticles of diameters between 1.

Clinical spectrum of reflux esophagitis among 25,536 Koreans who underwent a health check-up: a nationwide multicenter prospective, endoscopy-based study.

Background: Gastroesophageal reflux is a commonly encountered condition, but detailed data on reflux symptoms in Asian countries are lacking.

Goals: To evaluate the prevalence and to document the clinical spectrum of endoscopic reflux esophagitis (RE).

Study: A total 25,536 subjects underwent an upper gastrointestinal endoscopic examination as part of a health check, and completed a gastroesophageal reflux questionnaire.

Functional fusion mutant of Candida antarctica lipase B (CalB) expressed in Escherichia coli.

Candida antarctica lipase B (CalB) was functionally expressed in the cytoplasm of Escherichia coli Origami(DE3) with the N-terminus fusion of E. coli endogenous proteins. The previously-identified stress responsive proteins through comparative proteome analyses such as malate dehydrogenase (Mdh), spermidine/putrescine-binding periplasmic protein (PotD), and FKBP-type peptidyl-prolyl cis-trans isomerase (PPIases) (SlyD) dramatically increased the solubility of CalB in E.

Longitudinal assessment of hyperplasia using magnetic resonance imaging without contrast in a porcine arteriovenous graft model.

Rationale And Objectives: Chronic hemodialysis requires a vascular access that provides high blood-flow rates for the extracorporeal recirculation of blood. Synthetic arteriovenous (AV) grafts often fail because of clotting caused by underlying hyperplasia formation. The authors report the use of magnetic resonance (MR) imaging (MRI) without contrast agent to monitor tissue hyperplasia formation as well as luminal area in a porcine model of AV graft stenosis.

Methylation of the Tumor Suppressor Gene RUNX3 in Human Gastric Carcinoma.

Background/aims: RUNX3 (PEBP2alphaC/CBFA3/AML2) is a novel tumor suppressor gene in the human gastric carcinoma. The aims of this study were to determine the methylation of RUNX3 promoter and the association between RUNX3 methylation and the clinicopathological characteristics of patients with gastric carcinoma.

Methods: Seventy-nine patients with gastric carcinoma were studied prospectively from April 2005 to May 2007.

Antibiotic-associated diarrhea: candidate organisms other than Clostridium difficile.

Background/aims: The direct toxic effects of antibiotics on the intestine can alter digestive functions and cause pathogenic bacterial overgrowth leading to antibiotic-associated diarrhea (AAD). Clostridium difficile (C. difficile) is widely known to be responsible for 10 approximately 20% of AAD cases.

[Expression of MMP-2, HIF-1alpha and VEGF in colon adenoma and colon cancer].

Background/aims: This study was aimed to investigate the expression of matrix metalloproteinase-2 (MMP-2), hypoxia-inducible factor (HIF)-1alpha, and vascular endothelial growth factor (VEGF) in colonic adenoma-carcinoma sequence.

Methods: Thirty-two tissue samples of colon adenoma, 11 of early colon cancer and 36 of advanced colon cancer were collected by colonoscopic biopsy. Normal colonic tissues were also collected from the same subjects.

Primary esophageal adenoid cystic carcinoma.

Adenoid cystic carcinoma (ACC) is common in the salivary glands but rare in the esophagus. Routine esophagogastroscopy performed in a 54-year-old woman as part of a medical check-up revealed a submucosal tumor (1.5x1.

An association between obesity and the prevalence of colonic adenoma according to age and gender.

Background: Epidemiologic data on obesity as a risk factor for colonic adenoma with respect to gender have not yet been confirmed. Here, we aimed to compare the prevalence of colonic adenoma and of advanced polyps in age-stratified men and women at baseline, to examine the role of body mass index (BMI) on colonic adenoma risk according to age and gender, and to examine the influence of menopausal status.

Methods: A total of 1744 asymptomatic patients (946 men, 798 women) who underwent colonoscopy for cancer screening at Ewha Mokdong Hospital, Seoul, Korea, between February and June 2005, were eligible.

Emerging need for vaccination against hepatitis A virus in patients with chronic liver disease in Korea.

Vaccination against hepatitis A virus (HAV) is recommended for patients with chronic liver disease (CLD), but this has been deemed unnecessary in Korea since the immunity against HAV was almost universal in adults. However, this practice has never been reevaluated with respect to the changing incidence of adult acute hepatitis A. We retrospectively reviewed the medical records of 278 patients with acute hepatitis A diagnosed from January 1995 to November 2005 and prospectively tested 419 consecutive CLD patients from July to December 2005 for the presence of IgG anti-HAV.

Noninvasive determination of ligament strain with deformable image registration.

Ligament function and propensity for injury are directly related to regional stresses and strains. However, noninvasive techniques for measurement of strain are currently limited. This study validated the use of Hyperelastic Warping, a deformable image registration technique, for noninvasive strain measurement in the human medial collateral ligament using direct comparisons with optical measurements.

High-resolution DTI of a localized volume using 3D single-shot diffusion-weighted STimulated echo-planar imaging (3D ss-DWSTEPI).

Diffusion tensor MRI (DTI) using conventional single-shot (SS) 2D diffusion-weighted (DW)-EPI is subject to severe susceptibility artifacts. Multishot DW imaging (DWI) techniques can reduce these distortions, but they generally suffer from artifacts caused by motion-induced phase errors. Parallel imaging can also reduce the distortions if the sensitivity profiles of the receiver coils allow a sufficiently high reduction factor for the desired field of view (FOV).

A case of gastric tuberculosis mimicking advanced gastric cancer.

Tuberculosis of the stomach is quite rare, both as a primary or secondary infection. It can present as a facet of a multiorgan disease process or may result from immunodeficiency. Here, we report a rare, interesting case of gastric tuberculosis which morphologically mimicked advanced gastric cancer in a young, immunocompetent patient presenting with hematemesis and melena.

High-resolution DTI with 2D interleaved multislice reduced FOV single-shot diffusion-weighted EPI (2D ss-rFOV-DWEPI).

Diffusion tensor MRI (DTI), using single-shot 2D diffusion weighted-EPI (2D ss-DWEPI), is limited to intracranial (i.c.) applications far from the sinuses and bony structures, due to the severe geometric distortions caused by significant magnetic field inhomogeneities at or near the tissue-air or tissue-bone interfaces.

Improved accuracy and consistency in T1 measurement of flowing blood by using inversion recovery GE-EPI.

Problems associated with techniques currently used to measure the T1 of flowing blood are evaluated and a method to improve the consistency and repeatability of measurements is presented. Similar to some currently used techniques, the pulse sequence employs a nonselective adiabatic inversion pulse followed by a series of ECG-gated gradient echo EPI (echo planar imaging) images to obtain images where the blood (fluid) signal exhibits a T1-dependent inversion recovery signal from which the spin lattice relaxation constant (T1) of the flowing fluid can be measured. The new method combines curve fitting with a measure of the curve null point to acquire more accurate and consistent T1 values.

Triple contrast technique for black blood imaging with double inversion preparation.

This work reports on the development of a pulse sequence to simultaneously acquire proton density, T(1), and T(2) weighted images in a single magnetization prepared fast spin echo acquisition. The technique is based upon the application of a magnetization preparation consisting of a global inversion followed by slice-selective 180 degrees and 90 degrees pulses to prepare the signal of specific slices. Slices are acquired in an interleaved manner with time delays appropriate for the desired image contrasts.

High-resolution diffusion-weighted 3D MRI, using diffusion-weighted driven-equilibrium (DW-DE) and multishot segmented 3D-SSFP without navigator echoes.

In this work we report on the development of a novel technique for high-resolution diffusion-weighted (DW) MRI based upon 3D steady-state free precession (3D-SSFP). First the 3D-SSFP acquisition was segmented (each segment consisting of a series of RF pulses and gradient-recalled echoes), and then DW-driven equilibrium (DE) was inserted between each segment. The in-plane imaging matrix was typically 256 x 192 or 256 x 160, which resulted in high-resolution DW images.

The need for phase-encoding flow compensation in high-resolution intracranial magnetic resonance angiography.

Purpose: To demonstrate that the time delay between phase and frequency encoding and the presence of pulsatile blood flow in high-resolution time-of-flight (TOF) imaging of the intracranial arteries (especially near the circle of Willis) can distort the appearance of blood vessels and result in a cross-hatch-appearing artifact in surrounding tissue.

Materials And Methods: Two techniques to reduce the artifact, tri-directional flow compensation (3DFC) and elliptical-centric (EC) phase-encoding order, are investigated in five volunteer studies.

Results: 3DFC eliminates the pulsation-related artifacts and the vessel distortion.