Publications by authors named "KM Yoo"

In this paper, we demonstrated the design and experimental results of the near-infrared lab-on-a-chip optical biosensor platform that monolithically integrates the MRR and the on-chip spectrometer on the silicon-on-insulator (SOI) wafer, which can eliminate the external optical spectrum analyzer for scanning the wavelength spectrum. The symmetric add-drop MRR biosensor is designed to have a free spectral range (FSR) of ∼19 nm and a bulk sensitivity of ∼73 nm/RIU; then the drop-port output resonance peaks are reconstructed from the integrated spatial-heterodyne Fourier transform spectrometer (SHFTS) with the spectral resolution of ∼3.1 nm and the bandwidth of ∼50 nm, which results in the limit of detection of 0.

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Alterations in the intestinal microbial flora are known to cause various diseases, and many people routinely consume probiotics or prebiotics to balance intestinal microorganisms and the growth of beneficial bacteria. In this study, we selected a peptide from fish (tilapia) skin that induces significant changes in the intestinal microflora of mice and reduces the Firmicutes/Bacteroidetes ratio, which is linked to obesity. We attempted to verify the anti-obesity effect of selected fish collagen peptides in a high-fat-diet-based obese mouse model.

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Organoids, and in particular patient-derived organoids, have emerged as crucial tools for cancer research. Our organoid platform, which has supported patient-derived tumor organoids (PTOs) from a variety of tumor types, has been based on the use of hyaluronic acid (HA) and collagen, or gelatin, hydrogel bioinks. One hurdle to high throughput PTO biofabrication is that as high-throughput multi-well plates, bioprinted volumes have increased risk of contacting the sides of wells.

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On-chip broadband optical spectrometers that cover the entire tissue transparency window (λ = 650-1050 nm) with high resolution are highly demanded for miniaturized biosensing and bioimaging applications. The standard spatial heterodyne Fourier transform spectrometer (SHFTS) requires a large number of Mach-Zehnder interferometer (MZI) arrays to obtain a broad spectral bandwidth while maintaining high resolution. Here, we propose a novel type of SHFTS integrated with a subwavelength grating coupler (SWGC) for the dual-polarization bandpass sampling on the SiN platform to solve the intrinsic trade-off limitation between the bandwidth and resolution of the SHFTS without having an outrageous number of MZI arrays or adding additional active photonic components.

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Stratum corneum (SC) pH regulates skin barrier functions and elevated SC pH is an important factor in various inflammatory skin diseases. Acidic topical formulas have emerged as treatments for impaired skin barriers. Sodium proton exchanger 1 (NHE1) is an important factor in SC acidification.

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Currentthree-dimensional (3D) models of liver tissue have been limited by the inability to study the effects of specific extracellular matrix (ECM) components on cell phenotypes. This is in part due to limitations in the availability of chemical modifications appropriate for this purpose. For example, hyaluronic acid (HA), which is a natural ECM component within the liver, lacks key ECM motifs (e.

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The sudden rise of the worldwide severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic in early 2020 has called into drastic action measures to perform instant detection and reduce the rate of spread. Common clinical and nonclinical diagnostic testing methods have been partially effective in satisfying the increasing demand for fast detection point-of-care (POC) methods to slow down further spread. However, accurate point-of-risk diagnosis of this emerging viral infection is paramount as the need for simultaneous standard operating procedures and symptom management of SARS-CoV-2 will be the norm for years to come.

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Introduction: The stratum corneum (SC) is a skin barrier that consists of corneocytes, intercellular lipids, and corneodesmosomes. Ceramides are composed of sphingoid bases linked with various types of fatty acids (FAs), and they are an essential constituent of SC intercellular lipids. Among their subtypes, ceramide NP with a phytosphingosine base is especially important.

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Hydrogels have played a significant role in many applications of regenerative medicine and tissue engineering due to their versatile properties in realizing design and functional requirements. However, as bioengineered solutions are translated towards clinical application, new hurdles and subsequent material requirements can arise. For example, in applications such as cell encapsulation, drug delivery, and biofabrication, in a clinical setting, hydrogels benefit from being comprised of natural extracellular matrix-based materials, but with defined, controllable, and modular properties.

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Background And Aim: Sarcopenia has been suggested to be associated with chronic inflammation and insulin resistance. This study aimed to evaluate whether low muscle mass is associated with the incidence and recurrence of advanced colorectal adenoma.

Methods: We conducted a cohort study including 14 701 participants who underwent first-time screening colonoscopy between 2003 and 2012 and follow-up colonoscopy until 2017.

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Mid-infrared (mid-IR) absorption spectroscopy based on integrated photonic circuits has shown great promise in trace-gas sensing applications in which the mid-IR radiation directly interacts with the targeted analyte. In this paper, considering monolithic integrated circuits with quantum cascade lasers (QCLs) and quantum cascade detectors (QCDs), the InGaAs-InP platform is chosen to fabricate passive waveguide gas sensing devices. Fully suspended InGaAs waveguide devices with holey photonic crystal waveguides (HPCWs) and subwavelength grating cladding waveguides (SWWs) are designed and fabricated for mid-infrared sensing at λ = 6.

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Intermittent fasting (IMF) is a relatively new dietary approach to weight management, although the efficacy and adverse effects have not been full elucidated and the optimal diets for IMF are unknown. We tested the hypothesis that a one-meal-per-day intermittent fasting with high fat (HF) or protein (HP) diets can modify energy, lipid, and glucose metabolism in normal young male Sprague-Dawley rats with diet-induced obesity or overweight. Male rats aged 5 weeks received either HF (40% fat) or HP (26% protein) diets ad libitum (AL) or for 3 h at the beginning of the dark cycle (IMF) for 5 weeks.

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This study investigated total carotenoid content, comparative carotenoid composition, vitamin C content, and total antioxidant capacity of three citrus varieties which are Yuza (Citrus junos Sieb ex Tabaka), Kjool (Citrus unshiu Marcow), and Dangyooja (Citrus grandis Osbeck). Seven carotenoids were identified, with β-cryptoxanthin, astaxanthin, and zeaxanthin being predominant in citrus varieties. Ripening increased the total carotenoid in three citrus varieties.

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Background: Metabolic health is an emerging concept that is highly correlated with various metabolic complications, and adipocytokines have been causally linked to a wide range of metabolic diseases. Thus, this study compared serum adipocytokine levels according to metabolic health and obesity status.

Methods: Four hundred and fifty-six nondiabetic subjects (mean age, 40.

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Background: The hypertriglyceridemic waist (HTGW) phenotype is a simple and inexpensive screening parameter to identify people at increased risk of cardiovascular disease. We evaluated whether the HTGW phenotype predicts diabetes in urban Korean adults.

Methods: A total of 2,900 nondiabetic subjects (mean age 44.

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Background: Chronic kidney disease (CKD) is considered one of the most common risk factors for cardiovascular disease. Coronary artery calcification (CAC) is a potential mechanism that explains the association between renal function and cardiovascular mortality. We aimed to evaluate the association between renal function and CAC in apparently healthy Korean subjects.

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Background: Opportunistic infections are relatively rare in early human immunodeficiency virus infection, especially infection with Mycobacterium tuberculosis. Here, we report a patient who presented with acute human immunodeficiency virus and multidrug-resistant M. tuberculosis co-infections.

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Background/aims: Adenoma detection rate (ADR) is widely used as an index of colonoscopy quality management. Although advanced adenomas can be found less frequently than non-advanced adenomas, advanced adenomas have a higher clinical significance during screening for colorectal cancer. The aim of this study was to investigate the correlation between advanced and non-advanced ADR among colonoscopists.

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Article Synopsis
  • Temporary maintenance workers in petrochemical plants in Korea are exposed to carcinogens like benzene, raising concerns about cancer risk.
  • A study analyzed data from 14,698 male workers between 2002-2007, linking cancer and mortality rates to national registries.
  • The results indicated higher rates of oral and pharyngeal cancers in these workers, suggesting a possible link, and recommended further research with extended follow-up and exposure assessments.
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Trichloroethylene (TCE) has been widely used as a degreasing agent in many manufacturing industries. Recently, the International Agency for Research on Cancer presented "sufficient evidence" for the causal relationship between TCE and kidney cancer. The aim of this study was to review the epidemiologic evidences regarding the relationship between TCE exposure and kidney cancer in Korean work environments.

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Unlabelled: American ginseng (Panax quinquefolius L.) root health benefits include treatment of type 2 diabetes and this study evaluated the hypoglycemic effects of American red ginseng (ARG). ARG roots have increased bioactive phenolic contents, such as cinnamic acid and ferulic acid during the steaming process.

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Bioconversion of the isoflavonoid genistein to 2'- hydroxygenistein (2'-HG) was performed using isoflavone 2'-hydroxylase (CYP81E1) heterologously expressed in yeast. A monohydroxylated product was analyzed by liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) and NMR spectrometry and was identified as 2'-HG. An initial bioconversion rate of 6% was increased up to 14% under optimized conditions.

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Three citrus varieties grown in Korea, namely, Yuza (Citrus junos Sieb ex Tanaka), Kjool (Citrus unshiu Marcow), and Dangyooja (Citrus grandis Osbeck), were evaluated for their dietary fiber, total phenolics, total flavonoids, and total carotenoids as well as individual flavonoids composition. The biochemical characteristics of citrus varieties were examined by the antioxidant capacity (731 to 1221 micromol of Trolox equivalent/g), total phenolic (334 to 411 mg of chlorogenic acid equivalent/100 g), total flavonoid contents (214 to 281 mg of catechin equivalent/100 g), and total carotenoid contents (63 to 84 mg/100 g). Six flavonoids, including naringin, naringenin, hesperidin, hesperetin, neohesperidin, and luteolin, were tentatively identified.

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