Publications by authors named "Sung-Yeun Yang"

Structural arrangement and dimension play vital roles in wave transport and amplification as they can restrict the volume explored by the waves. However, it is challenging to systematically investigate the interplay among structural, optical, and mechanical properties, in part because of limited experimental platforms that modulate the structural arrangement in a continuous manner. We present light amplification action in Rhodamine B doped silk fibroin (SF) nanofibrous scaffolds and its modulation via the control of the alignment or directionality of SF nanofibers through an electrospinning procedure.

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The development of functional scaffolds with improved osteogenic potential is important for successful bone formation and mineralization in bone tissue engineering. In this study, we developed a functional electrospun silk fibroin (SF) nanofibrous scaffold functionalized with two-stage hydroxyapatite (HAp) particles, using mussel adhesive-inspired polydopamine (PDA) chemistry. HAp particles were first incorporated into SF scaffolds during the electrospinning process, and then immobilized onto the electrospun SF nanofibrous scaffolds containing HAp via PDA-mediated adhesive chemistry.

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Background & Aims: Prostaglandin E (PGE) is mediator of inflammation that regulates tissue regeneration, but its continual activation has been associated with carcinogenesis. Little is known about factors in the PGE signaling pathway that contribute to tumor formation. We investigated whether yes-associated protein 1 (YAP1), a transcriptional co-activator in the Hippo signaling pathway, mediates PGE function.

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Background/aims: Several studies suggest that pyogenic liver abscess (PLA) is associated with colon neoplasm. A colonoscopic exam for cryptogenic PLA might detect a hidden colon neoplasm, through which intestinal flora can be transmitted into the liver. However, there are no prospectively enrolled cross-sectional data for colonic neoplasm in cryptogenic PLA.

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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.

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Article Synopsis
  • * A case study details a young boy from Russia with AT who experienced abdominal pain, leading to diagnostic tests, including CT scans and colonoscopy.
  • * The boy was ultimately diagnosed with a rare type of colon cancer (signet ring cell), which is unusual for AT patients, highlighting the need for awareness of potential solid tumor risks in this population.
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Teratoma of mediastinum is rare germ cell tumor. Anterior mediastinum is the most common extragonadal site. Benign mediastinal teratoma accounts for 60% of all mediastinal germ cell tumors.

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Electrospun silk fibroin (SF) scaffolds have drawn much attention because of their resemblance to natural tissue architecture such as extracellular matrix, and the biocompatibility of SF as a candidate material to replace collagen. However, electrospun scaffolds lack the physical integrity of bone tissue scaffolds, which require resistance to mechanical loadings. In this work, we propose membrane-reinforced electrospun SF scaffolds by a serial process of electrospinning and freeze-drying of SF solutions in two different solvents: formic acid and water, respectively.

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Agents that promote tissue regeneration could be beneficial in a variety of clinical settings, such as stimulating recovery of the hematopoietic system after bone marrow transplantation. Prostaglandin PGE2, a lipid signaling molecule that supports expansion of several types of tissue stem cells, is a candidate therapeutic target for promoting tissue regeneration in vivo. Here, we show that inhibition of 15-hydroxyprostaglandin dehydrogenase (15-PGDH), a prostaglandin-degrading enzyme, potentiates tissue regeneration in multiple organs in mice.

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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.

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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.

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Background: 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.

Methods: 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.

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Local and prolonged delivery of local analgesics is much desired for post-operative pain management. For delivery of local analgesics at a constant rate over couple of days, a microfluidic device comprised of a drug reservoir and microchannels for drug release was developed using a biodegradable polymer, 85/15 poly(lactic-co-glycolic acid). Unlike conventional methods relying on material property, this device enables convenient modulation of the release speed of drugs by a simple change of the channel geometry such as the length and cross-sectional area.

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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.

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Purpose: To associate the global gene expression of B7/CD28 family transcripts with pathologic features of colon cancer, we determined the B7/CD28 family transcripts in peripheral blood mononuclear cells (PBMCs) from normal subjects and patients with adenomatous polyps and colon cancer, and correlated the results with pathologic features of colon cancer.

Methods: PBMCs from age-matched normal subjects and patients with adenomatous polyps and colon cancer were analyzed for peripheral blood transcripts (PBTs) of B7/CD28 family using real-time PCR. Differences in expression levels of B7/CD28 PBTs across all cancer stages and between colon cancer patients with or without microscopic lymphovascular invasion (LVI) were analyzed.

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Background/aims: Rabeprazole sodium is a potent proton pump inhibitor. We assessed the efficacy, safety and compliance of one-week triple therapy including rabeprazole with amoxicillin and clarithromycin for eradication of Helicobacter pylori (H. pylori).

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