Biology subjects

Youn, J.

Publications and source records attributed to Youn, J..

5 recordsLinked to original sources

bioRxiv2024

A genome-wide association study of high-sensitivity C-reactive protein in a large Korean population highlights its role in cholesterol metabolism

High-sensitivity C-reactive protein (hsCRP) is a representative biomarker of systemic inflammation and is associated with numerous complex diseases. To explore the biological pathways and functions underlying chronic inflammation, we conducted a genome-wide association study (GWAS) and several post-GWAS analyses of the hsCRP levels. This study was performed on data from 71,019 Koreans and is one of the largest East Asian studies. Overall, 69 independent single nucleotide polymorphisms (SNPs) were identified, including 12 novel variants located within SHE, RP11-740C1.2, FCRL6, STEAP1B, AC002480.5, TOMM7, SPPL3, RP11-216P16.6, RP11-209K10.2, CTC-490E21.12, CYP2F2P, CBLC, and PVRL2. The implicated genes and pathways are primarily involved in cholesterol metabolism and the immune response. A phenome-wide association study was performed based on a polygenic risk score constructed using 69 hsCRP-associated SNPs. Notably, the alleles associated with higher hsCRP levels appeared to be associated with lower low-density lipoprotein cholesterol levels (P=1.69 x 10-33, {beta}=-1.47). Our findings provide evidence of a link between hsCRP and cholesterol as well as the clinical importance of hsCRP. Specifically, we suggest that genetically determined hsCRP levels may be useful for predicting the potential risk of cardiovascular or other diseases related to lipid metabolism. Authors summaryChronic inflammation is associated with numerous complex diseases, including cancer, cardiovascular disease, and diabetes. Previous studies have shown that East Asians have lower levels of C-reactive protein (CRP), a biomarker of inflammation, than other ancestry groups. To identify East Asian-specific single nucleotide polymorphisms (SNPs) associated with chronic inflammation, we conducted a genome-wide association study and secondary genetic analyses on hsCRP in 71,019 Korean individuals. In total, 69 SNPs were identified, of which 12 were novel. A majority of the identified SNPs are located within genes (LEPR, IL6R, and APOE) that are involved in cholesterol metabolism and immune response. Notably, we found genetically determined hsCRP level may contribute to decrease cholesterol level, in contrast to previous epidemiological studies. Therefore, we suggest genetically determined hsCRP as a clinical tool for predicting the potential risk of abnormal cholesterol metabolism and its related diseases.

genomics↗

bioRxiv2024

FoodAtlas: Automated Knowledge Extraction of Food and Chemicals from Literature

Automated generation of knowledge graphs that accurately capture published information can help with knowledge organization and access, which have the potential to accelerate discovery and innovation. Here, we present an integrated pipeline to construct a large-scale knowledge graph using large language models in an active learning setting. We apply our pipeline to the association of raw food, ingredients, and chemicals, a domain that lacks such knowledge resources. By using an iterative active learning approach of 4,120 manually curated premise-hypothesis pairs as training data for ten consecutive cycles, the entailment model extracted 230,848 food-chemical composition relationships from 155,260 scientific papers, with 106,082 (46.0%) of them never been reported in any published database. To augment the knowledge incorporated in the knowledge graph, we further incorporated information from 5 external databases and ontology sources. We then applied a link prediction model to identify putative food-chemical relationships that were not part of the constructed knowledge graph. Validation of the 443 hypotheses generated by the link prediction model resulted in 355 new food-chemical relationships, while results show that the model score correlates well (R2 = 0.70) with the probability of a novel finding. This work demonstrates how automated learning from literature at scale can accelerate discovery and support practical applications through reproducible, evidence-based capture of latent interactions of diverse entities, such as food and chemicals.

bioinformatics↗

bioRxiv2022

Significantly amplified photoacoustic effect for silica-coated gold nanoparticles by interface heat transfer mechanisms

Plasmonic gold nanoparticles (AuNPs) are effective photoacoustic (PA) signal agents and have found important biomedical applications. The silica coating on the surface of AuNPs showed enhanced PA efficiency, however, the PA amplification mechanism remains unclear. Here, we systematically studied the silica coating effect on PA generation of AuNPs under different laser pulse durations. We experimentally demonstrated up to 4-fold PA amplification under thin silica coating (<5 nm) and a picosecond laser excitation. The theoretical model further suggests that the PA amplification originates from two interface heat transfer mechanisms including 1) the enhanced interface thermal conductance on the silica-water interface and 2) the electron-phonon energy transfer channel on the gold/silica interface. This study discovers a regime of large PA amplification and provides a new rationale for plasmonic nanoparticle design to achieve better PA efficiency.

bioengineering↗

bioRxiv2022

Optical Control Of Neuronal Activities With Photoswitchable Nanovesicles

Precise modulation of neuronal activity by neuroactive molecules is essential for understanding brain circuits and behavior. However, tools for highly controllable molecular release are lacking. Here, we developed a photoswitchable nanovesicle with azobenzene-containing phosphatidylcholine (azo-PC), coined azosome, for neuromodulation. Irradiation with 365 nm light triggers the trans-to-cis isomerization of azo-PC, resulting in a disordered lipid bilayer with decreased thickness and cargo release. Irradiation with 455 nm light induces reverse isomerization and switches the release off. Real-time fluorescence imaging shows controllable and repeatable cargo release within seconds (< 3 s). Importantly, we demonstrate that SKF-81297, a dopamine D1-receptor agonist, can be released from the azosome to activate cultures of primary striatal neurons. Azosome shows promise in precise optical control over the molecular release and can be a valuable tool for molecular neuroscience studies.

bioengineering↗

bioRxiv2021

Probing neuropeptide volume transmission in vivo by a novel all-optical approach

Neuropeptides are essential signaling molecules in the nervous system involved in modulating neural circuits and behavior. Although hypothesized to signal via volume transmission through G-protein coupled receptors (GPCR), remarkably little is known about their extrasynaptic diffusion. Here, we developed an all-optical approach to probe neuropeptide volume transmission in mouse neocortex. To control neuropeptide release, we engineered photosensitive nanovesicles with somatostatin-14 (SST) that is released with near-infrared light stimulation. To detect SST, we created a new cell-based neurotransmitter fluorescent engineered reporter (CNiFER) using the SST2 GPCR. Under two-photon imaging, we determined the time to activate SST2R at defined distances as well as the maximal distance and loss rate for SST volume transmission in neocortex. Importantly, we determined that SST transmission is significantly faster in neocortex with a chemically degraded extracellular matrix, a diseased condition indicated in neuroinflammation and Parkinsons disease. These new neurotechnologies can reveal important biological signaling processes previously not possible, and provide new opportunities to investigate volume transmission in the brain.

neuroscience↗