Publications by authors named "Yoon Sung Bae"

Optical scatterfield imaging microscopy technique which has the capability of controlling scattered fields in the imaging mode is useful for quantitative nanoscale dimensional metrology that yields precise characterization of nanoscale features for semiconductor device manufacturing process control. To increase the sensitivity in the metrology using this method, it is required to optimize illumination and collection optics that enhance scatterfield signals from the nanoscale targets. Partial coherence of the optical imaging system is used not only for enhancing image quality in the traditional microscopy or lithography but also for increasing the sensitivity of the scatterfield imaging microscopy.

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Purpose: To evaluate the feasibility of self-expanding metal stent (SEMS) placement and fluorescence microendoscopic monitoring for determination of fibroblast cell proliferation after stent placement in an esophageal mouse model.

Materials And Methods: Twenty fibroblast-specific protein (FSP)-1 green fluorescent protein (GFP) transgenic mice were analyzed. Ten mice (Group A) underwent SEMS placement, and fluoroscopic and fluorescence microendoscopic images were obtained biweekly until 8 weeks thereafter.

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Interstitial cystitis/bladder pain syndrome (IC/BPS) is an intractable disease characterized by severe pelvic pain and urinary frequency. Mesenchymal stem cell (MSC) therapy is a promising approach to treat incurable IC/BPS. Here, we show greater therapeutic efficacy of human embryonic stem cell (hESC)-derived multipotent stem cells (M-MSCs) than adult bone-marrow (BM)-derived counterparts for treating IC/BPS and also monitor long-term safety and in vivo properties of transplanted M-MSCs in living animals.

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Background: Gastric "crawling-type" adenocarcinoma (CRA) is a tumor histologically characterized by irregularly fused glands with low-grade cellular atypia that tends to spread laterally in the mucosa. To date, the expression characteristics of the key molecules involved in CRA, including receptor tyrosine kinases (RTKs), mismatch repair (MMR) proteins, phosphatase and tensin homolog (PTEN), as well as the Epstein-Barr virus (EBV) status, have yet to be uncovered.

Methods: We constructed tissue microarrays of 94 CRAs, 72 conventional-type differentiated adenocarcinomas (CDAs), and 71 intramucosal poorly cohesive adenocarcinomas (PCAs) from early gastric cancers to evaluate and compare the pathological and expression profiles of potential key molecules for molecular classification (EBV; four MMR proteins-MLH1, MSH2, PMS2, and MSH6; three RTKs-HER2, MET, and EGFR; PTEN; and p53).

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To investigate the clinicopathologic characteristics and the prognostic impact of PIK3CA gene amplification in curatively resected esophageal squamous cell carcinoma (ESCC). Using 534 curatively resected ESCCs, the PIK3CA gene copy number was evaluated with fluorescent in situ hybridization. PIK3CA amplification was defined as PIK3CA/centromere 3 ratio is ≥ 2.

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Objective: The aim of this study is to find the frequency and the role of epidermal growth factor receptor expression as a prognostic biomarker in gastric cancer.

Methods: We evaluated the prognostic value and frequency of epidermal growth factor receptor expression and amplification using immunohistochemistry and silver in situ hybridization in a large cohort of curatively resected gastric cancer.

Results: Of the total of 935 cases, 294 (31.

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Background: Epstein-Barr virus (EBV)-associated gastric cancer (GC) and microsatellite-instability-high GC are associated with a low prevalence of regional lymph node metastasis (LNM). To evaluate the feasibility of endoscopic treatment of EBV-associated and/or microsatellite-instability-high early GC (EGC), we analyzed the risk factors for LNM using a large series (n = 756) of submucosa-invasive (SM) EGC.

Methods: EBV-encoded RNA in situ hybridization (EBER ISH) and immunohistochemistry for four mismatch repair (MMR) proteins (MLH1, PMS2, MSH2, and MSH6) were performed.

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Background/aims: The usefulness of immunohistochemistry to screen for the microsatellite instability (MSI) phenotype in gastric cancer remains unclear. Moreover, the prognostic value of MSI phenotypes in gastric cancer has been debated.

Methods: The clinicopathologic parameters and survival outcomes of 203 MSI-high (MSI-H) and 261 microsatellite-stable (MSS) advanced gastric cancers (AGCs) were compared.

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Background: Some studies have reported lymph node metastasis (LNM) in early gastric cancer (EGC) cases meeting the expanded criteria for endoscopic resection. Therefore, we investigated whether a minor poorly differentiated carcinoma (PDC) component in the submucosal (SM) layer affects LNM in differentiated EGC.

Methods: We performed surgery in 1096 patients with differentiated SM gastric cancer and compared the clinicopathologic features of node-positive (n = 194) and node-negative (n = 902) differentiated SM cancer, with special reference to the portion of PDC component in the SM layer.

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To investigate the frequency and the prognostic impact of fibroblast growth factor receptor 1 (FGFR1) gene amplification in 526 curatively resected esophageal squamous cell carcinoma (ESCC). Using fluorescent in situ hybridization, high amplification was defined by an FGFR1/centromer 8 ratio is ≥ 2.0, or average number of FGFR1 signals/tumor cell nucleus ≥ 6.

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Volume measurement of a phase object is one of the most distinctive capabilities of quantitative phase microscopy (QPM). However, the accuracy of a measured volume is limited by the different noises of a measurement system and the finite bandpass filter used in the phase extraction algorithm. In this paper, we analyze the inherent errors in volume measurement with QPM and propose the optimum condition that can minimize these errors.

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We present a reduced-phase dual-illumination interferometer (RPDII) that measures the topography of a sample with large step height variation. We experimentally demonstrate the basic principle and the feasibility of this novel single-shot quantitative phase imaging. Two beams of this interferometer illuminate a sample at different incident angles, and two phases of the different incident angles and their phase difference are simultaneously recorded using three spatial frequencies.

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Background: Cerebrospinal fluid (CSF) examination can be used to verify the presence of primary malignancies as well as cases of central nervous system (CNS) metastasis. Because of its importance, there have been several studies concerning the sensitivity of CSF cytology. To determine the practical use and reproducibility of diagnoses based on CSF cytology, we evaluated this test by analyzing cytology results from consecutive CSF samples.

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Recently, there has been emerging concern that crescents, the main histologic feature of Henoch-Schönlein purpura nephritis, merely reflect active inflammation, and may not be useful in predicting long-term outcomes. We therefore conducted a single-center retrospective study to evaluate whether the new Oxford classification of immunoglobulin A nephropathy can be used to predict long-term outcome in patients with Henoch-Schönlein purpura nephritis. We included 61 biopsy-proven patients with Henoch-Schönlein purpura nephritis between January 1991 and August 2010.

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Background And Purpose: Malformation of cortical development (MCD) is a well-known cause of drug-resistant epilepsy and focal cortical dysplasia (FCD) is the most common neuropathological finding in surgical specimens from drug-resistant epilepsy patients. Palmini's classification proposed in 2004 is now widely used to categorize FCD. Recently, however, Blumcke et al.

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Pulmonary sclerosing hemangioma (PSH) is an uncommon lung neoplasm with a clinical outcome that is generally benign. However, differentiating PSH from pulmonary carcinoma is sometimes difficult as both lesions share similar histopathologic and immunohistochemical features. In this study, we investigated the usefulness of Ki-67 (MIB-1) immunostaining in the diagnosis of PSH.

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Synopsis of recent research by authors named "Yoon Sung Bae"

  • Yoon Sung Bae's recent research focuses on advanced imaging techniques and their applications in both semiconductor metrology and medical diagnostics, particularly in areas related to cancer and tissue engineering.
  • His work in optical scatterfield imaging microscopy has improved the sensitivity of dimensional measurements for nanoscale features, which is critical in semiconductor manufacturing.
  • Additionally, he has conducted significant studies on the progression and treatment of various cancer types, such as esophageal squamous cell carcinoma and gastric cancer, highlighting the prognostic value of genetic markers and implications for treatment strategies.