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Kyung Min Lee

Publications and source records attributed to Kyung Min Lee.

7 recordsLinked to original sources

Comparisons of Methods for Mucus Sampling and Mucin Semi-Quantification on Barramundi (Lates calcarifer) and Atlantic Salmon (Salmo salar) Epithelial Sites.

Fish epithelial surfaces are covered by a mucus layer. The highly glycosylated proteins called mucins are a main component of the mucus, which also contains a range of antibacterial enzymes, proteins, and peptides of importance for its protective properties. Here, we compared the practicality and yield of mucus harvesting from barramundi and Atlantic salmon epithelial sites using glass slide, swab, Super·SAL™ and whole tissue extract. We also compared the feasibility of using the orcinol assay, a glycan-on-membrane assay, and absorbance at 230 nm in combination with standard curves of pig gastric mucin to estimate the mucin concentration. Glycomics demonstrated that non-amine hexose content differed more between fish and tissues than terminal monosaccharides with cis-hydroxy groups, and that non-mucin molecules had a major impact on the A230-based results, making the glycan-on-membrane assay the most versatile method for estimating mucin concentration. We conclude that the most versatile tool for mucus harvesting was swabs, allowing for sufficient amounts of sample to be harvested with relative ease and low levels of contamination from the oral cavity, gill, skin, and intestine. Furthermore, the glycan-on-membrane assay was useful for measuring mucus concentration, and it was beneficial to estimate both sample concentration and purity by comparing samples at relatively similar concentrations.

Animals↗

Germline Variants Influence Chronic Liver Disease Progression through Distinct Pathways.

Cirrhosis and hepatocellular carcinoma (HCC) are long-term complications of chronic liver disease (CLD). In this large multi-ancestry genome-wide association study of all-cause cirrhosis (35,481 cases, 2.36M controls) and HCC (6,680 cases, 1.76M controls), we identified 27 loci associated with cirrhosis (10 novel) and 11 with HCC (three novel). Three novel cirrhosis loci were replicated in independent cohorts (e.g. FGF21, RPTOR, and IFNL3/4). Fifteen cirrhosis loci exhibited differential effects on cirrhosis risk via underlying etiologies, and six HCC loci influenced HCC risk indirectly via cirrhosis. In a gene-burden analysis of rare variants from whole-genome sequencing data in the VA Million Veteran Program (n=102,677), we identified GSTA5 as a novel cirrhosis-associated gene, while APOB and ATP9B were associated with and replicated for HCC. A high genetic risk score for cirrhosis was associated with a nearly doubled risk of CLD progressing to cirrhosis (HR=1.94, P=2×10-68) and of cirrhosis progressing to HCC (HR=1.65, P=7×10-08). Finally, among individuals with chronic hepatitis C who underwent antiviral therapy, cirrhosis risk was modified by variants in PNPLA3, IFNL3/4, and CD81 following pegylated interferon-α therapy, and by APOE lead variant following direct-acting antiviral therapy. These findings provide new insights into the complex genetic architecture of CLD progression with potential clinical and therapeutic implications.

Journal Article↗

Genomics-informed drug-repurposing strategy identifies two therapeutic targets for preventing liver disease associated with metabolic dysfunction.

Identification of drug-repurposing targets with genetic and biological support is an economically and temporally efficient strategy for improving the treatment of diseases. We employed a cross-disciplinary approach to identify potential therapeutics for the prevention of metabolic-dysfunction-associated steatotic liver disease (MASLD) in at-risk individuals by using humans as a model organism. We identified 212 putative candidate genes associated with MASLD by using data from a large multi-ancestry genetic association study, of which 158 (74.5%) were previously unreported. From this set, we identified 57 genes that encode for druggable protein targets and for which the effects of increasing genetically predicted gene expression on MASLD risk align with the function of that drug on the protein target. We then used We then evaluated these potential targets for evidence of efficacy by using Mendelian randomization, pathway analysis, and protein structural modeling. Through these approaches, we present compelling evidence to suggest that the activation of FADS1 by icosapent ethyl, as well as S1PR2 by fingolimod, could be a promising therapeutic strategy for MASLD prevention.

Humans↗

Water-soluble genistin glycoside isoflavones up-regulate antioxidant metallothionein expression and scavenge free radicals.

Genistin has antioxidant activities; however, its insolubility in water often limits its biological availability in vivo. Using a novel transglycosylation process, the solubility of genistin glycosides was increased 1000 to 10000-fold, but it was not known whether these modified genistin glycosides maintained antioxidant activity. We found that both genistin and its glycosides similarly up-regulated the transcription of several metallothionein (MT) antioxidant genes (MT1A, MT2A, MT1E, and MT1X), as well as the glucose 6-phosphate dehydrogenase (G6PD) gene in HepG2 cells. This gene induction was mediated by the sequestration of zinc in the cytosol, which up-regulated the metal-responsive transcription factor-1 (MTF-1) that induced MT gene expression. Although not as effective as ascorbic acid, genistin glycosides possessed slightly greater reducing power than genistin. We concluded that genistin and genistin glycosides have a direct antioxidant effect and an indirect antioxidant effect, perhaps via induction of MT by activity of MTF-1.

Antioxidants↗

Asymmetric end-functionalization of multi-walled carbon nanotubes.

Asymmetric end-functionalization of carbon nanotubes was achieved by sequentially floating a substrate-free aligned carbon nanotube film on two different photoreactive solutions with only one side of the nanotube film being contacted with the photoreactive solution and exposed to UV light each time. The resultant nanotubes with different chemical reagents attached onto their opposite tube-ends should be very useful for site-selective self-assembling of carbon nanotubes into many novel functional structures for various potential applications.

Journal Article↗

Intrapulmonary cystic lymphangioma in a 2-month-old infant.

Lymphangioma is an abnormal collection of lymphatics that are developmentally isolated from the normal lymphatic system. Lymphangioma rarely presents as a solitary pulmonary lesion. We report a rare case of intrapulmonary cystic lymphangioma involving the upper lobe of the right lung, which presented with dyspnea in a 2-month-old infant. High-resolution computed tomography (HRCT) of the chest demonstrated a well-circumscribed, multiseptate, cystic lesion in the upper lobe of the right lung, mimicking the feature of type I congenital cystic adenomatoid mal-formation. The tumor was removed by bilobectomy of the upper and middle lobes of the right lung, and its pathologic examination confirmed the diagnosis of an intra-pulmonary cystic lymphangioma.

Female↗

Effect of background motion on line bisection performance in normal subjects.

Previous studies have demonstrated that optokinetic stimulation (OKS) influences line bisection (LB) performance in normal subjects and patients with hemispatial neglect. Since subjects were required to attend to stationary targets on a moving background, prior experimental designs might have induced an illusion of target motion or induced motion (IM) in a direction opposite the background. The current study tested whether the IM affects LB performance in normal subjects and how the speed of targets also influences LB. Thirty-two right-handed normal volunteers (aged 28.0 +/- 5.3 years) were asked to bisect stationary lines with a background of horizontal OKS. These stimuli were generated by computer displayed on a large screen via a beam projector. The OKS was varied according to direction (leftward or rightward) and speed (9.4 degrees/sec or 56.1 degrees/sec), producing 4 different experimental conditions. Mean bisection errors in all conditions were compared with a control condition with no background OKS. For each condition, subjects rated the degree of IM on a 5 point scale. With fast rate OKS, subjects reported minimal IM and LB errors were in the same direction as background motion, a finding that replicates previous studies. Conversely, the slow OKS rate caused subjects to report IM and resulted in deviation of the bisection mark in a direction opposite the background OKS. While this discrepancy between the slow and fast OKS conditions might be related to motion illusion, we did not find a direct correlation between the degree of IM and bisection errors and thus reasons for these results remain unexplained.

Adult↗