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1.
Stud Health Technol Inform ; 315: 482-486, 2024 Jul 24.
Article in English | MEDLINE | ID: mdl-39049306

ABSTRACT

The digital transformation of healthcare in South Korea, accelerated by COVID-19, has led to increased focus on critically ill patients in large hospitals. To address this, a monitoring system was developed to ensure safe inpatient treatment and improve staff efficiency. This aligns with the Medical Data-Centric Hospitals initiative, which leverages data for healthcare innovation. The case study highlights the implementation of a ward critical care monitoring system, which has improved patient safety, work efficiency, and expanded patient monitoring scope. Key lessons include the importance of addressing technical and user challenges, aligning innovations with national policies, and the potential of data-driven solutions to tackle healthcare challenges.


Subject(s)
COVID-19 , Republic of Korea , Humans , Monitoring, Physiologic , Critical Care/organization & administration , SARS-CoV-2 , Patient Safety , Electronic Health Records
2.
Yonsei Med J ; 65(8): 456-462, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39048321

ABSTRACT

PURPOSE: External ear reconstruction has been a challenging subject for plastic surgeons for decades. Popular methods using autologous costal cartilage or polyethylene still have their drawbacks. With the advance of three-dimensional (3D) printing technique, bioscaffold engineering using synthetic polymer draws attention as an alternative. This is a clinical trial of ear reconstruction using 3D printed scaffold, presented with clinical results after 1 year. MATERIALS AND METHODS: From 2021 to 2022, five adult patients with unilateral microtia underwent two-staged total ear reconstruction using 3D printed implants. For each patient, a patient-specific 3D printed scaffold was designed and produced with polycaprolactone (PCL) based on computed tomography images, using fused deposition modeling. Computed tomography scan was obtained preoperatively, within 2 weeks following the surgery and after 1 year, to compare the volume of the normal side and the reconstructed ear. At 1-year visit, clinical photo was taken for scoring by two surgeons and patients themselves. RESULTS: All five patients had completely healed reconstructed ear at 1-year follow-up. On average, the volume of reconstructed ear was 161.54% of that of the normal side ear. In a range of 0 to 10, objective assessors gave scores 3 to 6, whereas patients gave scores 8 to 10. CONCLUSION: External ear reconstruction using 3D printed PCL implant showed durable, safe results reflected by excellent volume restoration and patient satisfaction at 1 year postoperatively. Further clinical follow-up with more cases and refinement of scaffold with advancing bioprinting technique is anticipated. The study's plan and results have been registered with the Clinical Research Information Service (CRIS No. 3-2019-0306) and the Ministry of Food and Drug Safety (MFDS No. 1182).


Subject(s)
Congenital Microtia , Plastic Surgery Procedures , Printing, Three-Dimensional , Humans , Plastic Surgery Procedures/methods , Male , Adult , Female , Congenital Microtia/surgery , Polyesters , Prostheses and Implants , Young Adult , Ear, External/surgery , Ear, External/abnormalities , Tomography, X-Ray Computed , Tissue Scaffolds , Treatment Outcome , Adolescent
3.
J Am Chem Soc ; 146(18): 12645-12655, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38651821

ABSTRACT

The increased production of plastics is leading to the accumulation of plastic waste and depletion of limited fossil fuel resources. In this context, we report a strategy to create polymers that can undergo controlled depolymerization by linking renewable feedstocks with siloxane bonds. α,ω-Diesters and α,ω-diols containing siloxane bonds were synthesized from an alkenoic ester derived from castor oil and then polymerized with varied monomers, including related biobased monomers. In addition, cyclic monomers derived from this alkenoic ester and hydrosiloxanes were prepared and cyclized to form a 26-membered macrolactone containing a siloxane unit. Sequential ring-opening polymerization of this macrolactone and lactide afforded an ABA triblock copolymer. This set of polymers containing siloxanes underwent programmed depolymerization into monomers in protic solvents or with hexamethyldisiloxane and an acid catalyst. Monomers afforded by the depolymerization of polyesters containing siloxane linkages were repolymerized to demonstrate circularity in select polymers. Evaluation of the environmental stability of these polymers toward enzymatic degradation showed that they undergo enzymatic hydrolysis by a fungal cutinase from Fusarium solani. Evaluation of soil microbial metabolism of monomers selectively labeled with 13C revealed differential metabolism of the main chain and side chain organic groups by soil microbes.


Subject(s)
Fusarium , Polymerization , Siloxanes , Siloxanes/chemistry , Plant Oils/chemistry , Polymers/chemistry , Molecular Structure , Carboxylic Ester Hydrolases
4.
Cancers (Basel) ; 16(4)2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38398169

ABSTRACT

Intratumor heterogeneity leads to different responses to targeted therapies, even within patients whose tumors harbor identical driver oncogenes. This study examined clinical outcomes according to a patient-derived cell (PDC)-based drug sensitivity test in lung cancer patients treated with targeted therapies. From 487 lung cancers, 397 PDCs were established with a success rate of 82%. In 139 PDCs from advanced non-small-cell lung cancer (NSCLC) patients receiving targeted therapies, the standardized area under the curve (AUC) values for the drugs was significantly correlated with their tumor response (p = 0.002). Among 59 chemo-naive EGFR/ALK-positive NSCLC patients, the PDC non-responders showed a significantly inferior response rate (RR) and progression-free survival (PFS) for the targeted drugs than the PDC responders (RR, 25% vs. 78%, p = 0.011; median PFS, 3.4 months [95% confidence interval (CI), 2.8-4.1] vs. 11.8 months [95% CI, 6.5-17.0], p < 0.001). Of 25 EGFR-positive NSCLC patients re-challenged with EGFR inhibitors, the PDC responder showed a higher RR than the PDC non-responder (42% vs. 15%). Four patients with wild-type EGFR or uncommon EGFR-mutant NSCLC were treated with EGFR inhibitors based on their favorable PDC response to EGFR inhibitors, and two patients showed dramatic responses. Therefore, the PDC-based drug sensitivity test results were significantly associated with clinical outcomes in patients with EGFR- or ALK-positive NSCLC. It may be helpful for predicting individual heterogenous clinical outcomes beyond genomic alterations.

5.
Materials (Basel) ; 16(17)2023 Aug 29.
Article in English | MEDLINE | ID: mdl-37687592

ABSTRACT

In this study, surface modification aimed to enhance the compatibility between a hydrophilic inorganic filler and polypropylene (PP) matrix using hydrophobic treatment. Lauric acid, butyl acrylate, and maleic anhydride were employed to modify the filler surface. After treatment, inorganic filler/PP composites were produced using melt-mixing and extrusion-injection molding processes. The study focused on investigating compatibility and migration behavior between the filler and matrix. The findings indicated that hydrophobic modification, specifically with butyl acrylate and maleic anhydride, improved migration issues in nano-whisker, while maintaining favorable mechanical properties even under accelerated thermal aging. However, excessive hydrophobicity induced by superhydrophobic treatment using lauric acid led to reduced compatibility with the matrix, compromising its effectiveness. Consequently, the study revealed the potential of surface modification to enhance interfacial properties and mitigate migration concerns in PP composites for automotive applications.

6.
Cancers (Basel) ; 15(14)2023 Jul 11.
Article in English | MEDLINE | ID: mdl-37509231

ABSTRACT

Although molecular subtypes of small-cell lung cancer (SCLC) have been proposed, their clinical relevance and therapeutic implications are not fully understood. Thus, we aimed to refine molecular subtypes and to uncover therapeutic targets. We classified the subtypes based on gene expression (n = 81) and validated them in our samples (n = 87). Non-SCLC samples were compared with SCLC subtypes to identify the early development stage of SCLC. Single-cell transcriptome analysis was applied to dissect the TME of bulk samples. Finally, to overcome platinum resistance, we performed drug screening of patient-derived cells and cell lines. Four subtypes were identified: the ASCL1+ (SCLC-A) subtype identified as TP53/RB-mutated non-SCLC representing the early development stage of SCLC; the immune activation (SCLC-I) subtype, showing high CD8+/PD-L1+ T-cell infiltration and endothelial-to-mesenchymal transition (EndMT); the NEUROD1 (SCLC-N) subtype, which showed neurotransmission process; and the POU2F3+ (SCLC-P) subtype with epithelial-to-mesenchymal transition (EMT). EndMT was associated with the worst prognosis. While SCLC-A/N exhibited platinum sensitivity, the EndMT signal of SCLC-I conferred platinum resistance. A BET inhibitor suppressed the aggressive angiogenesis phenotype of SCLC-I. We revealed that EndMT development contributed to a poor outcome in SCLC-I. Moreover, heterogenous TME development facilitated platinum resistance. BET inhibitors are novel candidates for overcoming platinum resistance.

7.
Br J Cancer ; 128(12): 2186-2196, 2023 06.
Article in English | MEDLINE | ID: mdl-37059804

ABSTRACT

BACKGROUND: In EGFR-mutant and MET-amplified lung cancer resistant to EGFR inhibitors, double blockade of EGFR and MET is considered as a reasonable strategy despite increasing toxicity. This study evaluated the single MET inhibition in these specific tumours. METHODS: We investigated the efficacy of a single MET inhibitor in EGFR-mutant, MET-amplified lung cancer cells (HCC827GR) and the matched clinical cases and patient-derived cells. Acquired resistance mechanisms to single MET inhibitor were further explored. RESULTS: Single MET inhibitor sufficiently inhibited the EGFR downstream signalling and proliferation in the HCC827GR cells. The MET-inhibitor-sensitive clones had similar EGFR mutation allele frequency as the MET-inhibitor-resistant clones. The patients with EGFR-mutant, MET-amplified lung cancer resistant to EGFR inhibitors showed definite response to single MET inhibitor but the response duration was not durable. The MET gene copy number in their plasma circulating tumour DNA was significantly decreased during the treatment and was not re-increased after progression. In the cells resistant to single MET inhibitor, the EGFR pathway was reactivated, and gefitinib alone successfully suppressed their growth. CONCLUSIONS: Single MET inhibition produced a short-lived response in EGFR-mutant and MET-amplified lung cancer. A further study of a novel combination therapy schedule is needed to achieve long-lasting efficacy and less toxicity.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Drug Resistance, Neoplasm/genetics , ErbB Receptors/genetics , ErbB Receptors/metabolism , Gefitinib , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use , Mutation , Cell Line, Tumor , Proto-Oncogene Proteins c-met/genetics
8.
J Exp Clin Cancer Res ; 42(1): 37, 2023 Jan 30.
Article in English | MEDLINE | ID: mdl-36717865

ABSTRACT

BACKGROUND: A pharmacogenomic platform using patient-derived cells (PDCs) was established to identify the underlying resistance mechanisms and tailored treatment for patients with advanced or refractory lung cancer. METHODS: Drug sensitivity screening and multi-omics datasets were acquired from lung cancer PDCs (n = 102). Integrative analysis was performed to explore drug candidates according to genetic variants, gene expression, and clinical profiles. RESULTS: PDCs had genomic characteristics resembled with those of solid lung cancer tissues. PDC molecular subtyping classified patients into four groups: (1) inflammatory, (2) epithelial-to-mesenchymal transition (EMT)-like, (3) stemness, and (4) epithelial growth factor receptor (EGFR)-dominant. EGFR mutations of the EMT-like subtype were associated with a reduced response to EGFR-tyrosine kinase inhibitor therapy. Moreover, although RB1/TP53 mutations were significantly enriched in small-cell lung cancer (SCLC) PDCs, they were also present in non-SCLC PDCs. In contrast to its effect in the cell lines, alpelisib (a PI3K-AKT inhibitor) significantly inhibited both RB1/TP53 expression and SCLC cell growth in our PDC model. Furthermore, cell cycle inhibitors could effectively target SCLC cells. Finally, the upregulation of transforming growth factor-ß expression and the YAP/TAZ pathway was observed in osimertinib-resistant PDCs, predisposing them to the EMT-like subtype. Our platform selected XAV939 (a WNT-TNKS-ß-catenin inhibitor) for the treatment of osimertinib-resistant PDCs. Using an in vitro model, we further demonstrated that acquisition of osimertinib resistance enhances invasive characteristics and EMT, upregulates the YAP/TAZ-AXL axis, and increases the sensitivity of cancer cells to XAV939. CONCLUSIONS: Our PDC models recapitulated the molecular characteristics of lung cancer, and pharmacogenomics analysis provided plausible therapeutic candidates.


Subject(s)
Lung Neoplasms , Pharmacogenetics , Humans , Phosphatidylinositol 3-Kinases/genetics , ErbB Receptors/metabolism , Drug Resistance, Neoplasm/genetics , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use , Phosphoinositide-3 Kinase Inhibitors/pharmacology , Cell Line, Tumor , Mutation , Epithelial-Mesenchymal Transition/genetics
9.
Stem Cell Res ; 66: 102986, 2023 02.
Article in English | MEDLINE | ID: mdl-36493708

ABSTRACT

CRISPR/Cas9-based transcriptional regulation systems can induce the site-specific activation or repression of endogenous genes. p300 is a transcriptional co-activator that functions as a histone acetyltransferase that regulates gene transcription via chromatin remodeling. Here, we generated a human embryonic stem cell line stably expressing catalytically dead Cas9 (dCas9) fused to the catalytic core domain of human p300 via lentiviral transduction. This cell line can be used for locus-specific histone acetylation in combination with guide RNAs, and is a valuable tool for gene regulation in stem cell research.


Subject(s)
CRISPR-Associated Protein 9 , Human Embryonic Stem Cells , Humans , CRISPR-Associated Protein 9/genetics , CRISPR-Cas Systems/genetics , Gene Expression Regulation , Transcription Factors/genetics , Cell Line , Transcriptional Activation
10.
Transl Lung Cancer Res ; 11(9): 1967-1972, 2022 Sep.
Article in English | MEDLINE | ID: mdl-36248327

ABSTRACT

Background: Capmatinib, a potent and selective mesenchymalepithelial transition factor (MET) inhibitor, is an effective treatment option for non-small cell lung cancer (NSCLC) patients with MET exon 14 skipping mutations or gene amplification. However, the mechanisms that confer resistance to capmatinib remain elusive. Here, we present a case of primary resistance to capmatinib in a MET-amplified NSCLC patient which was conferred by concurrent MYC amplification. Case Description: Capmatinib was administered as first-line treatment in an 82-year-old MET-amplified [gene copy number (GCN) 13.5] and MET overexpressed (immunohistochemical staining 3+/3, >50%) NSCLC patient. However, the tumor rapidly progressed and showed primary resistance to capmatinib. Next-generation target sequencing using rebiopsy tumor samples revealed MYC amplification. We also performed functional drug susceptibility testing using patient-derived cells (PDCs), which showed overexpression of MYC mRNA and resistance to capmatinib. Meanwhile, ICX-101, an investigational MYC inhibitor, successfully inhibited the growth of PDCs at a relatively low IC50 value. Also, a synergistic effect was shown when capmatinib treatment was followed by ICX-101. Conclusions: Concurrent MYC amplification could potentially confer primary resistance to capmatinib in highly MET amplified NSCLC patients. Further clinical studies are warranted to corroborate these findings, and treatment with MYC inhibitors could be suggested as an alternative therapeutic strategy for this subset of patients.

11.
Biomaterials ; 286: 121575, 2022 07.
Article in English | MEDLINE | ID: mdl-35598335

ABSTRACT

Human in vitro hepatic models that faithfully recapitulate liver function are essential for successful basic and translational research. A limitation of current in vitro models, which are extensively used for drug discovery and toxicity testing, is the loss of drug metabolic function due to the low expression and activity of cytochrome P450 (CYP450) enzymes. Here, we aimed to generate human pluripotent stem cell-derived hepatic organoids (hHOs) with a high drug metabolic ability. We established a two-step protocol to produce hHOs from human pluripotent stem cells for long-term expansion and drug testing. Fully differentiated hHOs had multicellular composition and exhibited cellular polarity and hepatobiliary structures. They also displayed remarkable CYP450 activity and recapitulated the metabolic clearance, CYP450-mediated drug toxicity, and metabolism. Furthermore, hHOs successfully modeled Wilson's disease in terms of Cu metabolism, drug responses, and diagnostic marker expression and secretion. In conclusion, hHOs exhibit high capacity for drug testing and disease modeling. Hence, this hepatic model system provides an advanced tool for studying hepatic drug metabolism and diseases.


Subject(s)
Induced Pluripotent Stem Cells , Pluripotent Stem Cells , Cell Differentiation , Humans , Induced Pluripotent Stem Cells/metabolism , Liver/metabolism , Models, Biological , Organoids/metabolism
12.
ACS Biomater Sci Eng ; 7(9): 4230-4243, 2021 09 13.
Article in English | MEDLINE | ID: mdl-33538598

ABSTRACT

Chondroitin sulfate (CS), the main component of cartilage extracellular matrix, has attracted attention as a biomaterial for cartilage tissue engineering. However, current CS hydrogel systems still have limitations for application in successful cartilage tissue engineering owing to their unsuitable degradation kinetics, insufficient mechanical similarity, and lack of integration with the native cartilage tissue. In this study, using mussel adhesive-inspired catechol chemistry, we developed a functional CS hydrogel that exhibits tunable physical and mechanical properties as well as excellent tissue adhesion for efficient integration with native tissues. Various properties of the developed catechol-functionalized CS (CS-CA) hydrogel, including swelling, degradation, mechanical properties, and adhesiveness, could be tailored by varying the conjugation ratio of the catechol group to the CS backbone and the concentration of the CS-CA conjugates. CS-CA hydrogels exhibited significantly increased modulus (∼10 kPa) and superior adhesive properties (∼3 N) over conventional CS hydrogels (∼hundreds Pa and ∼0.05 N). In addition, CS-CA hydrogels incorporating decellularized cartilage tissue dice promoted the chondrogenic differentiation of human adipose-derived mesenchymal stem cells by providing a cartilage-like microenvironment. Finally, the transplantation of autologous cartilage dice using tissue-adhesive CS-CA hydrogels enhanced cartilage integration with host tissue and neo-cartilage formation owing to favorable physical, mechanical, and biological properties for cartilage formation. In conclusion, our study demonstrated the potential utility of the CS-CA hydrogel system in cartilage tissue reconstruction.


Subject(s)
Hydrogels , Tissue Adhesives , Cartilage , Chondroitin Sulfates , Humans , Tissue Engineering
13.
Phys Chem Chem Phys ; 22(32): 17867-17879, 2020 Aug 24.
Article in English | MEDLINE | ID: mdl-32766621

ABSTRACT

Steady-state and transient absorption spectra with <50 fs time resolution were obtained for two conjugated polymers, both with ≈200 conjugated double bonds (N), constrained in planar, stable, polyene frameworks. Solutions of the polymers exhibit the same S2 → S1 → S* → S0 decay pathway observed for the N = 11-19 polyene oligomers and for zeaxanthin homologues with N = 11-23. Comparisons with the excited state dynamics of polydiactylene and a much longer, more disordered polyene polymer (poly(DEDPM)) show that the S2, S1, and S* lifetimes of the four polymers are almost identical. The S* signals in the polymers are assigned to absorption from vibrationally excited ground states. In spite of significant heterogeneities and variations in conjugation lengths in these long polyenes, their S0 → S2 absorptions are vibronically-resolved in room temperature solutions with electronic origins at ≈600 nm. The limiting wavelength for the S0 → S2 transitions is consistent with the persistence of bond length alternation in the electronic ground states and a HOMO-LUMO band gap in polyenes with N ≈ 200. The coincidence of the well-resolved S0 → S2 electronic origins and the convergence of the excited state lifetimes in the four polymers point to a common, "nearly infinite" polyene limit.

14.
Biomed Mater ; 15(5): 055026, 2020 08 21.
Article in English | MEDLINE | ID: mdl-32526712

ABSTRACT

Nanoparticle-enhanced coatings of bone implants are a promising method to facilitate sustainable wound healing, leading to an increase in patient well-being. This article describes the in vitro characterization of osteoblast cells interacting with polyelectrolyte multilayers, which contain detonation nanodiamonds (NDs), as a novel class of carbon-based coating material, which presents a unique combination of photoluminescence and drug-binding properties. The cationic polyelectrolyte, namely polydiallyldimethylammonium chloride (PDDA), has been used to immobilize NDs on silica glass. The height of ND-PDDA multilayers varies from a minimum of 10 nm for one bilayer to a maximum of 90 nm for five bilayers of NDs and PDDA. Human fetal osteoblasts (hFOBs) cultured on ND-PDDA multilayers show a large number of focal adhesions, which were studied via quantitative fluorescence imaging analysis. The influence of the surface roughness on the filopodia formation was assessed via scanning electron microscopy and atomic force microscopy. The nano-rough surface of five bilayers constrained the filopodia formation. The hFOBs grown on NDs tend to show not only a similar cell morphology compared to cells cultured on extracellular matrix protein-coated silica glass substrates, but also increased cell viability by about 40%. The high biocompatibility of the ND-PDDA multilayers, indicated via high cell proliferation and sound cell adhesion, shows their potential for biomedical applications such as drug-eluting coatings and biomaterials in general.


Subject(s)
Bone Substitutes , Nanodiamonds , Osteoblasts/drug effects , Biocompatible Materials , Cell Adhesion , Cell Proliferation , Cell Survival , Cells, Cultured , Electrolytes , Humans , In Vitro Techniques , Lipid Bilayers/chemistry , Luminescence , Microscopy, Atomic Force , Microscopy, Electron, Scanning , Microscopy, Fluorescence , Nanotechnology/methods , Polyelectrolytes , Polyethylenes/chemistry , Quaternary Ammonium Compounds/chemistry , Silicon Dioxide/chemistry , Surface Properties , Wound Healing
15.
Adv Biosyst ; 4(8): e2000092, 2020 08.
Article in English | MEDLINE | ID: mdl-32500640

ABSTRACT

Nanotopography mimicking extracellular environments reportedly impact cell morphological changes; however, elucidating this relationship has been challenging. To control cellular responses using nanostructures, in this study, the quantitative relationship between nanotopography and cell spreading mediated by focal adhesions (FAs) is demonstrated using adipose-derived stem cells (ASCs). The spreading of ASCs and area of FAs are analyzed for the distribution of filamentous actin and vinculin, respectively, using fluorescent images. FAs require a specific area for adhesion (herein defined as effective contact area [ECA]) to maintain cell attachment on nanopillar arrays. An ECA is the area of FAs supported by nanopillars, multiplying the area fraction (AF) of their top surface. Regarding the spreading of cells, the mean area of ASCs linearly decreases as the mean area of FAs increases. Because the area of FAs is inversely correlated to the AF of the nanopillar arrays, the spreading of cells can be quantitatively correlated with nanotopography. The results provide a conceptual framework for controlling cell behaviors to design artificial substrates for tissue-engineering applications.


Subject(s)
Adipocytes/cytology , Fluorocarbons/pharmacology , Focal Adhesions/drug effects , Silanes/pharmacokinetics , Stem Cells/cytology , Adipocytes/drug effects , Adipocytes/physiology , Adipose Tissue/cytology , Adipose Tissue/drug effects , Adipose Tissue/physiology , Cell Adhesion/drug effects , Cell Differentiation/drug effects , Cell Movement/drug effects , Fatty Acids , Focal Adhesions/ultrastructure , Humans , Nanostructures/chemistry , Nanostructures/ultrastructure , Stem Cells/drug effects , Stem Cells/physiology , Tissue Engineering/methods
16.
FASEB J ; 34(7): 9141-9155, 2020 07.
Article in English | MEDLINE | ID: mdl-32421247

ABSTRACT

Human-induced pluripotent stem cells (hiPSCs) are invaluable sources for drug screening and toxicity tests because of their differentiation potential and proliferative capacity. Recently, the CRISPR-Cas9-mediated homologous recombination system has enabled reporter knock-ins at desired loci in hiPSCs, and here, we generated a hiPSC reporter line expressing mCherry-tagged cytochrome P450 1A1 (CYP1A1), which can be utilized to screen for the modulators of aryl hydrocarbon receptor (AHR) in live cells. CYP1A1-mCherry hiPSCs exhibited typical characteristics of pluripotent stem cells such as marker expression, differentiation potential, and normal karyotype. After differentiation into hepatocyte-like cells (HLCs), CYP1A1-mCherry fusion protein was expressed and localized at the endoplasmic reticulum, and induced by AHR agonists. We obtained 23 hits modulating CYP1A1 expression from high-content screening with 241 hepatotoxicity chemicals and nuclear receptor ligands, and identified three upregulating chemicals and two downregulating compounds. Responses of hiPSC-HLCs against an AHR agonist were more similar to human primary hepatocytes than of HepG2 hepatocellular carcinoma cells. This platform has the advantages of live-cell screening without sacrificing cells (unlike previously available CYP1A1 reporter cell lines), as well as an indefinite supply of cells, and can be utilized in a wide range of screening related to AHR- and CYP1A1-associated diseases in desired cell types.


Subject(s)
Cytochrome P-450 CYP1A1/chemistry , Fluorescence , Hepatocytes/cytology , Induced Pluripotent Stem Cells/cytology , Pharmaceutical Preparations/metabolism , Small Molecule Libraries/pharmacology , Cell Differentiation , Cytochrome P-450 CYP1A1/metabolism , Hep G2 Cells , Hepatocytes/drug effects , High-Throughput Screening Assays , Humans , Induced Pluripotent Stem Cells/drug effects , Induced Pluripotent Stem Cells/enzymology , Signal Transduction
17.
Int J Mol Sci ; 21(6)2020 Mar 24.
Article in English | MEDLINE | ID: mdl-32213906

ABSTRACT

An adenoviral vector (Ad) expressing a Wnt decoy receptor (sLRP6E1E2) is known to induce an anti-fibrotic effect by inhibiting Wnt signaling. We evaluated its effects in vivo using pig models and attempted to introduce an alginate gel-matrix system to prolong the effect of the Ad. Transduction efficiency as to the biological activity of Ad in different forms was evaluated. Then, 50 days after the formation of full-thickness skin defects on the backs of Yorkshire pigs, scars were treated with each form of Ad. Therapeutic efficacy and various factors influencing scar formation and collagen rearrangement were analyzed. Inflammatory cell infiltration within the scar tissues was also evaluated. Decoy Wnt receptor (sLRP6E1E2)-expressing adenovirus treatment improved scar quality in a pig model. Loading this construct in alginate gel allows sustained virus release into local tissues and prolongs Ad activity, thus maintaining its therapeutic effect longer in vivo.


Subject(s)
Adenoviridae/genetics , Alginates/chemistry , Cicatrix/therapy , Genetic Therapy/methods , Receptors, Wnt/genetics , Animals , Collagen/genetics , Collagen/metabolism , Gene Transfer Techniques , Hydrogels/chemistry , Receptors, Wnt/metabolism , Skin/metabolism , Swine , Wnt Signaling Pathway
18.
Sci Rep ; 10(1): 5586, 2020 03 27.
Article in English | MEDLINE | ID: mdl-32221392

ABSTRACT

The first member of the velvet family of proteins, VeA, regulates sexual development and secondary metabolism in the filamentous fungus Aspergillus nidulans. In our study, through comparative proteome analysis using wild type and veA-deletion strains, new putative regulators of sexual development were identified and functionally analyzed. Among these, SvfA, containing a yeast survival factor 1 domain, plays multiple roles in the growth and differentiation of A. nidulans. Deletion of the svfA gene resulted in increased sensitivity to oxidative and cold stress as in yeast. The svfA-deletion strain showed an increase in bi-polar germination and a decrease in radial growth rate. The deletion strain formed structurally abnormal conidiophores and thus produced lower amounts of conidiospores during asexual development. The svfA-deletion strain produced few Hülle cells and small cleistothecia with no ascospores, indicating the requirement of svfA for the completion of sexual development. Transcription and genetic analyses indicated that SvfA modulates the expression of key development regulatory genes. Western blot analysis revealed two forms of SvfA. The larger form showed sexual-specific and VeA-dependent production. Also, the deletion of svfA caused decreased ST (sterigmatocystin) production. We propose that SvfA is a novel central regulator of growth, differentiation and secondary metabolism in A. nidulans.


Subject(s)
Aspergillus nidulans/growth & development , Fungal Proteins/physiology , Aspergillus nidulans/genetics , Blotting, Western , Gene Expression Regulation, Fungal/genetics , Reproduction , Spores, Fungal/growth & development
19.
Appl Microsc ; 50(1): 26, 2020 Nov 17.
Article in English | MEDLINE | ID: mdl-33580331

ABSTRACT

The biocompatible polyurethane acrylate (PUA) nanopillars were fabricated by soft lithography using three different sizes of nanobeads (350, 500, and 1000 nm), and the human adipose-derived stem cells (hASCs) were cultured on the nanopillars. The hASCs and their various behaviors, such as cytoplasmic projections, migration, and morphology, were observed by high resolution images using a scanning electron microscope (SEM). With the accurate analysis by SEM for the controlled sizes of nanopillars, the deflections are observed at pillars fabricated with 350- and 500-nm nanobeads. These high-resolution images could offer crucial information to elucidate the complicated correlations between nanopillars and the cells, such as morphology and cytoplasmic projections.

20.
Childs Nerv Syst ; 36(1): 145-151, 2020 01.
Article in English | MEDLINE | ID: mdl-30879128

ABSTRACT

PURPOSE: Non-activated platelet-rich plasma (nPRP) slowly releases growth factors that induce bone regeneration. Adipose tissue-derived stem cells (ASCs) are also known to induce osteoblast differentiation. In this study, we investigated the combined effect of nPRP and ASC treatment compared with single therapy on bone regeneration. METHODS: Thirty New Zealand white rabbits with 15 × 15 mm2 calvarial defects were randomly divided into four treatment groups: control, nPRP, ASC, or nPRP + ASC groups. For treatment, rabbits received a collagen sponge (Gelfoam®) saturated with 1 ml normal saline (controls), 1 ml non-activated PRP (nPRP group), 2 × 106 ASCs (ASCs group), or 2 × 106 ASCs plus l ml nPRP (nPRP + ASCs group). After 16 weeks, bone volume and new bone surface area were measured, using three-dimensional computed tomography and digital photography. Bone regeneration was also histologically analyzed. RESULTS: Bone surface area in the nPRP group was significantly higher than both the control and ASC groups (p < 0.001 and p < 0.01, respectively). The percentage of regenerated bone surface area in the nPRP + ASC group was also significantly higher than the corresponding ratios in the control group (p < 0.001). The volume of new bone in the nPRP group was increased compared to the controls (p < 0.05). CONCLUSION: Our results demonstrate that slow-releasing growth factors from nPRP did not influence ASC activation in this model of bone healing. PRP activation is important for the success of combination therapy using nPRP and ASCs.


Subject(s)
Platelet-Rich Plasma , Adipose Tissue , Animals , Bone Regeneration , Osteogenesis , Rabbits , Stem Cells
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