Publications by authors named "Jun-Woo Kim"

We investigated how the positional arrangement of electron-donating (amino) and electron-withdrawing (ester) groups in single benzene-based fluorophores influences their emission properties. By synthesizing 26 regioisomeric fluorophores, we achieved wavelength modulation from 322 to 539 nm, revealing key correlations between functional group positioning and photophysical behavior.

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In this study, we investigated the potential mechanisms by which polyhexamethylene guanidine phosphate (PHMG-p), a known respiratory irritant, may contribute to lung cancer development. Using the adverse outcome pathway (AOP) framework, we analyzed established databases (such as AOP-Wiki) and employed AI tools (AOP-helpFinder) to identify key events (KEs) associated with lung carcinogenesis. Our analysis indicates that chronic inhalation of PHMG-p triggers a non-genotoxic pathway, characterized by cell membrane disruption, inflammation, and oxidative stress, with a point of departure (POD) of 0.

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Current human risk assessments often rely on animal toxicity data to establish point of departure (POD) values, followed by the application of uncertainty factors. Consequently, there is growing interest in alternative toxicity testing methods that reduce reliance on animal models. In this study, we propose a novel approach for inhalation toxicity risk assessment that integrates in silico and in vitro methods.

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Human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) have emerged as a promising tool for studying cardiac physiology and drug responses. However, their use is largely limited by an immature phenotype and lack of high-throughput analytical methodology. In this study, we developed a high-throughput testing platform utilizing hPSC-CMs to assess the cardiotoxicity and effectiveness of drugs.

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Objectives: Exposure to humidifier disinfectants has been linked to respiratory diseases, including interstitial lung disease, asthma, and pneumonia. Consequently, numerous toxicological studies have explored respiratory damage as both a necessary and sufficient condition for these diseases. We systematically reviewed and integrated evidence from toxicological studies by applying the evidence integration method established in previous research to confirm the biological plausibility of the association between exposure and disease.

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Next-generation risk assessment (NGRA) has emerged as a promising alternative to non-animal studies owing to the increasing demand for the risk assessment of inhaled toxicants. In this study, NGRA was used to assess the inhalation risks of two biocides commonly used as humidifier disinfectants: polyhexamethylene guanidine phosphate (PHMG-p) and chloromethylisothiazolinone/methylisothiazolinone (CMIT/MIT). Human bronchial epithelial cell transcriptomic data were processed based on adverse outcome pathways and used to establish transcriptome-based points of departure (tPODs) for each biocide.

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Primary cutaneous mucinous carcinoma (PCMC) is a rare malignancy of the sweat glands that most commonly affects the periorbital area. It is characterized by slow growth over a prolonged period, and its morphology can be easily confused with a benign tumor, such as an epidermal cyst. Consequently, many patients experience recurrence after undergoing multiple resections.

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Recent advances in single-photon femtosecond spectroscopy have highlighted the power of entangled photons in probing the properties of materials, previously inaccessible through semiclassical spectroscopic approaches. In this study, we theoretically propose a new single-photon-based femtosecond time-resolved spectroscopy technique termed single-photon transient stimulated emission (SP-TSE). SP-TSE not only enables the selective investigation of singly excited superposition states but also harnesses the quantum mechanical nature of photons for the efficient data acquisition of transient responses, thereby supporting the feasibility of experimental realization of SP-TSE.

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An in-house Python-based algorithm was developed using simplified molecular-input line-entry specification (SMILES) strings and a dipole moment for estimating the normal boiling point, critical properties, standard enthalpy, vapor pressure, liquid molar volume, enthalpy of vaporization, heat capacity, viscosity, thermal conductivity, and surface tension of molecules. Normal boiling point, critical properties, and standard enthalpy were estimated by using the Joback group contribution method. Vapor pressure, liquid molar volume, enthalpy of vaporization, heat capacity, and surface tension were estimated by using the Riedel model, Gunn-Yamada model, Clausius-Clapeyron equation, Joback group contribution method, and Brock-Bird model, respectively.

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Understanding photoinduced chemical reactions beyond the Born-Oppenheimer paradigm requires a comprehensive examination of vibronic interactions. Although femtosecond studies have unveiled the influence of vibrational modes strongly coupled to ultrafast intramolecular reactions in the excited state, they often lack direct observations of how vibrations modulate electronic properties due to the rapid disappearance of reactants. To address this gap, our research investigates the dynamics of photoexcited molecules that do not react.

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Background: The clinical characteristics of pediatric nasal fractures can vary depending on the child's age, social activities, and environment. Therefore, this study aimed to analyze these characteristics in different age groups.

Methods: We retrospectively reviewed of a series of patients aged under 12 years who received treatment between 2013 and 2021.

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Objective: The purpose of this study was to evaluate the impact of preimplantation genetic testing for aneuploidy (PGT-A) on clinical outcomes among high-risk patients.

Methods: This retrospective study involved 1,368 patients and the same number of cycles, including 520 cycles with PGT-A and 848 cycles without PGT-A. The study participants comprised women of advanced maternal age (AMA) and those affected by recurrent implantation failure (RIF), recurrent pregnancy loss (RPL), or severe male factor infertility (SMF).

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Article Synopsis
  • Attempts to develop drugs targeting the corticotropin-releasing hormone receptor 1 (CRFR) for stress-related therapy have not been successful so far.
  • High-resolution studies using X-ray free-electron lasers (XFELs) aided in understanding GPCR structures, leading to the elucidation of the CRFR's crystal structure with a specific antagonist.
  • Two new antagonists, BMK-C203 and BMK-C205, were developed, with BMK-C205 showing significant antidepressant effects in mice, suggesting potential for effective drug development against CRFR.
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Hemihyperplasia is a kind of regional body growth asymmetry and can be a symptom of several congenital disorders and tumorous conditions. Torticollis is most commonly caused by asymmetric hypertrophy of the sternocleidomastoid muscle. Herein, we report a case of hemihyperplasia in an infant with ipsilateral torticollis.

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The dynamics of a liquid and its coupling to a solute are crucial for a better understanding of chemical processes in the liquid phase. In isotropic and homogeneous solutions, the time-correlation function of a solute is expected to vanish over time due to the translational and diffusive motions of the solvent. The three-pulse photon echo peak shift (3PEPS) is a third-order nonlinear spectroscopy technique that records the time-correlation function of a solute molecule in a solution, including an offset (inhomogeneity).

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Aim: To evaluate the influence of insemination methods on clinical outcomes by assessing preimplantation genetic testing for aneuploidy (PGT-A) outcomes in embryos obtained using in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) in sibling mature oocytes from high-risk patients.

Methods: This retrospective study involved 108 couples with nonmale or mild male factor infertility who underwent split insemination cycles from January 2018 to December 2021. PGT-A was performed using trophectoderm biopsy, array comparative genome hybridization, or next-generation sequencing with 24-chromosome screening.

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Drug repositioning has gained significant attention over the past several years. The anti-rheumatoid arthritis drug auranofin has been investigated for the treatment of other diseases, including liver fibrosis. Because auranofin is rapidly metabolized, it is necessary to identify the active metabolites of auranofin that have detectable levels in the blood and reflect its therapeutic effects.

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Polyhexamethylene guanidine phosphate (PHMG-p), used as a humidifier disinfectant, causes interstitial lung disease, obliterative bronchiolitis, and lung fibrosis; however, little is known about its effect on intercellular interactions. Extracellular vesicles (EVs), which carry diverse compounds including proteins, RNA, and DNA to mediate cell-to-cell communication through their paracrine effects, have been highlighted as novel factors in lung fibrogenesis. This study aimed to identify the effect of proteins on small EVs (sEVs) from bronchoalveolar lavage fluid (BALF) of the recipient cells after PHMG-p exposure.

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The detection of high levels of microplastics in indoor and outdoor air has increased concerns regarding its toxic effects on the respiratory system. They are not easily degradable and can be deposited deep in the lungs. Although several studies have reported inhalation toxicities of microplastics, they are still controversial due to a lack of evidence.

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Rationale: Subcutaneous and epidural abscesses following epidural injection are a serious but rare complication. Epidural abscesses are typically caused by Staphylococcus aureus bacterial infection. In this case presented here, the causative bacterium was Enterococcus faecalis.

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Guillain-Barre syndrome (GBS) is an immune-mediated acute polyradiculoneuropathy and commonly occurs after a preceding infection or immunization sequalae. Following the severe acute respiratory syndrome-coronavirus-2 virus pandemic with co-introduction of massive vaccinations, several GBS cases associated with coronavirus disease 2019 (COVID-19) infection per se or after vaccination for COVID-19 were reported internationally. Herein, we report two cases of Korean GBS presenting with tetraplegia after two different COVID-19 vaccinations (42-year old man by AstraZeneca and 48-year woman by Pfizer vaccines) within four weeks after vaccination.

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We carried out transient absorption spectroscopy of thioflavin T (ThT) molecules in various solvents employing an asynchronous optical sampling (ASOPS) scheme with dual synchronized and frequency up-converted mode-lock lasers in the near UV (NUV) spectral region. We developed a pair of synchronized femtosecond lasers with tunable center wavelengths ranging from 380 to 430 nm and spectral bandwidths of 30 nm. As a proof-of-principle experiment, we measured interferometrically detected time and frequency-resolved pump-probe signals of ThT in various solvents to study the twisted intramolecular charge transfer process of photo-excited ThT molecules.

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Exciton relaxation dynamics in multichromophore systems are often modeled using Redfield theory, where bath fluctuations mediate the relaxation among the exciton eigenstates. Identifying the vibrational or phonon modes that are implicated in exciton relaxation allows more detailed understanding of exciton dynamics. Here we focus on a well-studied light-harvesting II complex (LH2) isolated from the photosynthetic purple bacterium strain 10050.

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The sphingosine-1-phosphate-1 (S1P) receptor agonists have great potential for the treatment of multiple sclerosis (MS) because they can inhibit lymphocyte egress through receptor internalization. We designed and synthesized triazole and isoxazoline derivatives to discover a novel S1P agonist for MS treatment. Of the two scaffolds, the isoxazoline derivative was determined to have excellent efficacy and drug-like properties.

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