Publications by authors named "Ah-Young Yoo"

Background: Patients undergoing dual antiplatelet therapy (DAPT) may experience recurrent gastrointestinal bleeding (GIB). We investigated the clinical characteristics and risk factors for recurrent non-variceal upper gastrointestinal bleeding (NVUGIB) in patients who had experienced NVUGIB while receiving DAPT.

Methods: We enrolled patients diagnosed with NVUGIB while receiving DAPT between 2006 and 2020.

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Background/aims: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors in the stomach. We evaluated the clinical outcomes of endoscopic treatment for gastric GISTs.

Methods: This is a single center, retrospective study that enrolled 135 cases of gastric subepithelial tumors (SETs) resected by endoscopic procedures and confirmed as GISTs by histopathology from March 2005 to July 2019.

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Gastric cancer (GC) and liver cirrhosis (LC) have high incidence rates, particularly in Eastern Asia; however, the long-term clinical outcomes or recurrence of GC following endoscopic submucosal dissection (ESD) in patients with comorbid LC remain unclear. The present study aimed to compare the long-term efficacy and safety of ESD in patients with GC, with and without LC. Patients with early GC (EGC) who had underlying LC and underwent endoscopic treatment (LC-EGC group) were enrolled in the present study.

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Claudin (CLDN) is a tight junction protein found in human epithelial cells and its altered expression is known to be associated with the progression of gastric cancer. We aimed to investigate the differential expression of CLDN-4 in early gastric cancer (EGC) according to its clinicopathological characteristics. We enrolled 53 patients with EGC who underwent surgical gastric resection from January 2007 to December 2018.

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Background/aims: Small bowel malignancies often present a diagnostic challenge due to their relative rarity and nonspecific clinical symptoms. However, technical developments in endoscopic instruments, including video capsule endoscopy (VCE) and enteroscopy, have allowed for the visualization of the entire small bowel. This study aimed to investigate the clinicopathological features of small bowel malignant tumors diagnosed by VCE and double-balloon enteroscopy (DBE) in a single tertiary center.

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The mechanisms through which cancer‑upregulated gene 2 (CUG2), a novel oncogene, affects Wnt/β‑catenin signaling, essential for tumorigenesis, are unclear. In this study, we aimed to elucidate some of these mechanisms in A549 lung cancer cells. Under the overexpression of CUG2, the protein levels and activity of β‑catenin were evaluated by western blot analysis and luciferase assay.

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Iron supplements such as ferrous sulfate tablets are usually used to treat iron-deficiency anemia in some elderly patients with primary neurologic disorders or decreased gag reflexes due to stroke, senile dementia, or parkinsonism. While the aspiration of ferrous sulfate is rarely reported, it is a potentially life-threatening condition that can lead to airway necrosis and bronchial stenosis. A detailed history and high suspicion of aspiration are required to avoid delays in diagnosis and treatment.

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A serine protease-producing marine bacterial strain named as PT-1 was isolated and identified as a family of Marinomonas arctica, based on molecular characterization of 16S rRNA gene sequence, phylogenetic tree, and fatty acid composition analyses. Optimized culture conditions for growth of the bacterium PT-1 and production of protease (ProA) were determined to be pH 8.0 in the presence of 5 % NaCl, at 37 °C during 24 h of incubation in the presence of 1.

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Edwardsiella tarda causes an infectious fish disease called edwardsiellosis. Several outer membrane proteins (OMPs) are associated with virulence factors and are attractive as vaccine candidates. In this study, 4 immuno-reactive OMPs of E.

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Expression of thin aggregative fimbriae (Agf) in Salmonella, which is responsible for bacterial cell adhesion to surfaces, aggregation, and formation of biofilms, is regulated by a complex mechanism. In order to identify gene(s) involved in the expression of Agf, the TnphoA transposon was introduced into Salmonella typhimurium χ8505 for random mutagenesis. Colonies showing a change from wrinkly-rough morphology to the smooth form were screened for candidates.

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The Dps protein, which is overexpressed in harsh environments, is known to play a critical role in the protection of DNA against oxidative stresses. In this study, the roles of Fur in the expression of the dps gene in Salmonella and the protection mechanisms against oxidative stress in Salmonella cells preexposed to iron-stress were investigated. Two putative Fur boxes were predicted within the promoter region o f th e S.

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In order to induce high levels of protein secretion, we have constructed a recombinant plasmid, designated pBP244, into which was incorporated key components of the type-II Sec-dependent secretion system, including LepB (signal peptidase), SecA (ATPase), and SecB (chaperone). The biological activities of the LepB, SecA, and SecB components expressed from genes harbored by pBP244 appeared to play their normal roles. In order to evaluate the protein secretion, a pspA (Streptococcus pneumoniae surface protein A) gene was cloned into pBP244, resulting in pBP438.

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