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1.
Pharmaceutics ; 16(6)2024 Jun 16.
Article in English | MEDLINE | ID: mdl-38931935

ABSTRACT

EGFRvIII is expressed only in tumor cells and strongly in glioblastoma and is considered a promising target in cancer diagnosis and therapy. Aptamers are synthetic single-stranded oligonucleotides that bind to biochemical target molecules with high binding affinity and specificity. This study examined the potential of the 68Ga-NOTA-EGFRvIII aptamer as a nuclear imaging probe for visualizing EGFRvIII-expressing glioblastoma by positron emission tomography (PET). EGFRvIII aptamer was selected using the SELEX technology, and flow cytometry and fluorescence microscopy verified the high binding affinity to EGFRvIII positive U87MG vIII 4.12 glioma cells but not to EGFRvIII negative U87MG cells. The EGFRvIII aptamer was conjugated with a chelator (1,4,7-triazanonane-1,4,7-triyl)triacetic acid (NOTA) for 68Ga-labeling. The 68Ga-NOTA-EGFRvIII aptamer was prepared using the preconcentration-based labeling method with a high radiolabeling yield at room temperature. Ex vivo biodistribution analyses confirmed the significantly higher tumor uptake of the 68Ga-NOTA-EGFRvIII aptamer in EGFRvIII-expressing xenograft tumors than that in EGFRvIII negative tumors, confirming the specific tumor uptake of the 68Ga-NOTA-EGFRvIII aptamer in vivo. PET imaging studies revealed a high retention rate of the 68Ga-NOTA-EGFRvIII aptamer in U87MG vIII 4.12 tumors but only low uptake levels in U87-MG tumors, suggesting that the 68Ga-NOTA-EGFRvIII aptamer may be used as a PET imaging agent for EGFRvIII-expressing glioblastoma.

2.
Clin Lab ; 69(1)2023 Jan 01.
Article in English | MEDLINE | ID: mdl-36649524

ABSTRACT

BACKGROUND: Nephrin is a protein in the glomerular podocyte slit diaphragm; therefore, its presence in urine implies damage to podocytes. This study aimed to determine the usefulness of nephrin as a biomarker in maternal urine to predict preeclampsia (PE). METHODS: This prospective study included pregnant women admitted for delivery at Seoul National University Bundang Hospital from March 2019 to May 2020. Patients who had been diagnosed with PE were included, and patients without a history of underlying diseases were recruited for the control group. Pertinent clinical data were collected. Urine samples were obtained, and nephrin signaling was detected through test strips using a lateral flow assay. The point-of-care test results were compared between patients with PE and without (control group), using the exact concentration of nephrin by enzyme-linked immunosorbent assay. RESULTS: Clinical characteristics - maternal age, parity, proportion of twin pregnancies, height, weight, and cesarean delivery rate - were comparable between the PE and control groups. Nephrin signals were classified into four groups. In the PE group, signals 0, 1, 2, and 3 were found in 18.4% (9/49), 44.9% (22/49), 24.5% (12/49), and 12.2% (6/49) of participants, respectively. Results were significantly different in the control group, in which 84.3% (43/51) were found to have signal 0 (p < 0.001). CONCLUSIONS: Nephrin signaling in maternal urine could be a noninvasive and useful test for early detection of severity of PE.


Subject(s)
Podocytes , Pre-Eclampsia , Humans , Pregnancy , Female , Pre-Eclampsia/diagnosis , Prospective Studies , Membrane Proteins/metabolism , Podocytes/metabolism
3.
Exp Ther Med ; 22(3): 1029, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34373715

ABSTRACT

Whole-exome sequencing (WES) analysis has been used recently as a diagnostic tool for finding molecular defects. In the present study, researchers attempted to analyze molecular defects through WES in a 13-year-old female patient who had not been diagnosed through a conventional genetic approach. DNA was extracted and subjected to WES analysis to identify the genetic defect. A total of 106,728 exons and splicing variants were selected, and synonymous single nucleotide variants (SNVs) and general single nucleotide polymorphisms (SNPs) were filtered out. Finally, nonsynonymous SNVs (c.C415T and c.C389T) of the PYGM gene were identified in nine compound heterozygous mutations. PYGM encodes myophosphorylase and degrades glycogen in the muscle to supply energy to muscle cells. The present study revealed that the patient's father had a c.C389T mutation and the mother had a c.C415T mutation, resulting in A130V and R139W missense mutations, respectively. To the best of our knowledge, the A130V variant in PYGM has not been reported in the common variant databases. All variations of the patient's family detected using WES were verified by Sanger sequencing. Because the patient had compound heterozygous mutations in the PYGM gene, the patient was presumed to exhibit markedly decreased muscle phosphorylase activity. To assess the function of myophosphorylase, an ischemic forearm exercise test was performed. The blood ammonia level sharply increased and the lactate level maintained a flat curve shape similar to the typical pattern of McArdle disease. Therefore, the diagnosis of the patient was confirmed to be McArdle disease, a glycogen storage disease. Through WES analysis, accurate and early diagnosis could be made in the present study. This report describes a novel compound heterozygous mutation of the PYGM gene in a Korean patient.

4.
Clin Chim Acta ; 518: 116-122, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33775700

ABSTRACT

Gitelman syndrome (GS) is an autosomal recessive disorder caused by loss-of-function mutations in SLC12A3, which encodes the Na-Cl cotransporter (NCC). Osteogenesis imperfecta (OI) is an autosomal dominant disorder caused by the inheritance of mutations mainly in the COL1A1 gene, resulting in bone fragility and deformity. In this study, we aimed to investigate the clinical and genetic manifestations in a 7-year-old boy with OI, who had electrolyte abnormalities and his four family members. Complete sequence analysis of COL1A1 revealed a novel mutation, c.268G>T, p.Glu90del. The gene mutation of OI in the patient's older brother was inherited from his mother, and the younger brother had no mutation. Two pathogenic mutations (c.179C>T, p.Thr60Met and c.1763C>T, p.Ala588Val) in SLC12A3 resulting in GS were also identified in the patient. The OI-related genetic mutation in the patient was consistent with that in the patient's mother. The GS-related genetic mutations were inherited from each parent. This study is the first to identify compound heterozygous variants in the SLC12A3 gene and a novel mutation in the COL1A1 gene in patients with OI and GS. Our findings indicate that genetic analysis is recommended to differentiate GS from BS, as clinical manifestations do not provide an accurate diagnosis.


Subject(s)
Gitelman Syndrome , Osteogenesis Imperfecta , Child , Genetic Testing , Gitelman Syndrome/genetics , Humans , Male , Mutation , Osteogenesis Imperfecta/complications , Osteogenesis Imperfecta/diagnosis , Osteogenesis Imperfecta/genetics , Pedigree , Solute Carrier Family 12, Member 3/genetics
5.
Nat Commun ; 12(1): 48, 2021 Jan 04.
Article in English | MEDLINE | ID: mdl-33397929

ABSTRACT

The ability of two nearly-touching plasmonic nanoparticles to squeeze light into a nanometer gap has provided a myriad of fundamental insights into light-matter interaction. In this work, we construct a nanoelectromechanical system (NEMS) that capitalizes on the unique, singular behavior that arises at sub-nanometer particle-spacings to create an electro-optical modulator. Using in situ electron energy loss spectroscopy in a transmission electron microscope, we map the spectral and spatial changes in the plasmonic modes as they hybridize and evolve from a weak to a strong coupling regime. In the strongly-coupled regime, we observe a very large mechanical tunability (~250 meV/nm) of the bonding-dipole plasmon resonance of the dimer at ~1 nm gap spacing, right before detrimental quantum effects set in. We leverage our findings to realize a prototype NEMS light-intensity modulator operating at ~10 MHz and with a power consumption of only 4 fJ/bit.

6.
Int Forum Allergy Rhinol ; 11(2): 144-152, 2021 02.
Article in English | MEDLINE | ID: mdl-32623837

ABSTRACT

BACKGROUND: Chronic rhinosinusitis (CRS) is an inflammatory disease of the sinonasal mucosa. Thymic stromal lymphopoietin (TSLP) is associated with T-helper 2 (Th2) response and induced by pathogen, allergen, toll-like receptor (TLR) ligands, and cytokines. Fibroblasts are known to be modulators of wound-healing, from inflammation to tissue remodeling. We examined effect of lipopolysaccharide (LPS) on TSLP production and the underlying mechanisms. We aimed to determine whether the effects of commonly used medications in CRS, namely corticosteroids, and macrolides, are related to LPS-induced TSLP in nasal fibroblasts. METHODS: Fibroblasts were isolated from inferior turbinate tissues of CRS patients. TSLP and TLR4 expressions were determined by reverse transcript-polymerase chain reaction (RT-PCR), Western blot, enzyme-linked immunoassay, and immunofluorescence staining. Mitogen-activated protein kinase (MAPK), protein kinase B (Akt), and nuclear factor-kappaB (NF-κB) phosphorylation was determined by Western blot and/or luciferase assay. RESULTS: LPS increased TSLP expression in a dose- and time-dependent manner. LPS antagonist and corticosteroids inhibited TLR4 expression in LPS-stimulated fibroblasts. LPS-RS, macrolides, corticosteroids, and specific inhibitors suppressed LPS-induced alterations. Ex vivo culture showed similar results. CONCLUSION: LPS induces TSLP production via the TLR4, MAPK, Akt, and NF-κB pathways. The effects of corticosteroids and macrolides are related to LPS-induced TSLP expression. We explored new treatment modalities targeting LPS-induced TSLP production that could replace the currently used corticosteroid and macrolides for treatment of CRS.


Subject(s)
Lipopolysaccharides , Proto-Oncogene Proteins c-akt , Adrenal Cortex Hormones/pharmacology , Cells, Cultured , Cytokines , Fibroblasts , Humans , Macrolides/pharmacology , Mitogen-Activated Protein Kinases , NF-kappa B , Toll-Like Receptor 4/genetics , Thymic Stromal Lymphopoietin
7.
Biomolecules ; 10(6)2020 06 22.
Article in English | MEDLINE | ID: mdl-32580467

ABSTRACT

(1) Background: Tissue remodeling and extracellular matrix (ECM) accumulation contribute to the development of chronic inflammatory diseases of the upper airway. Endoplasmic reticulum (ER) stress is considered to be the key signal for triggering tissue remodeling in pathological conditions. The present study aimed to investigate the role of ER-stress in TGF-ß1-stimulated nasal fibroblasts and inferior turbinate organ cultures; (2) Methods: Fibroblasts and organ cultures were pretreated with 4-phenylbutyric acid (PBA) and stimulated with TGF-ß1 or thapsigargin (TG). Expression of ER-stress markers, myofibroblast marker, and ECM components was measured by Western blotting and real-time PCR. Reactive oxygen species (ROS) were quantified using 2',7'-dichlorofluorescein diacetate. Cell migration was evaluated using Transwell assays. Contractile activity was measured by collagen contraction assay; (3) Results: 4-PBA inhibited TGF-ß1 or TG-induced ER-stress marker expression, phenotypic changes, and ECM. Pre-treatment with ROS scavengers inhibited the expression of TGF-ß1-induced ER-stress markers. Migration and collagen contraction of TGF-ß1 or TG-stimulated fibroblasts were ameliorated by 4-PBA treatment. These findings were confirmed in ex vivo organ cultures; (4) Conclusions: 4-PBA downregulates TGF-ß1-induced ER-stress marker expression, migration, and collagen contraction via ROS in fibroblasts and organ cultures. These results suggest that ER-stress may play an important role in progression of chronic upper airway inflammatory diseases by aiding pathological tissue remodeling.


Subject(s)
Endoplasmic Reticulum Stress , Fibroblasts/metabolism , Transforming Growth Factor beta1/metabolism , Turbinates/metabolism , Biomarkers/analysis , Biomarkers/metabolism , Cells, Cultured , Endoplasmic Reticulum Chaperone BiP , Endoplasmic Reticulum Stress/drug effects , Extracellular Matrix/drug effects , Fibroblasts/drug effects , Heat-Shock Proteins/antagonists & inhibitors , Heat-Shock Proteins/genetics , Heat-Shock Proteins/metabolism , Humans , Phenylbutyrates/pharmacology , Reactive Oxygen Species/analysis , Reactive Oxygen Species/metabolism , Transforming Growth Factor beta1/antagonists & inhibitors , Turbinates/drug effects , X-Box Binding Protein 1/antagonists & inhibitors , X-Box Binding Protein 1/genetics , X-Box Binding Protein 1/metabolism
8.
J Diabetes Res ; 2019: 2510105, 2019.
Article in English | MEDLINE | ID: mdl-31467925

ABSTRACT

BACKGROUND: Epithelial-to-mesenchymal transition (EMT) is thought to play a significant role in the advancement to chronic kidney disease and contributes to the deposition of extracellular matrix proteins and renal fibrosis relating to diabetic nephropathy. METHOD: We studied the effect of Nrf2-HO-1 signaling on high-glucose- (HG-) induced EMT in normal human tubular epithelial cells, that is, HK2 cells. In short, we treated HK2 cells with HG and sulforaphane (SFN) as an Nrf2 activator. EMT was evaluated by the expression activity of the epithelial marker E-cadherin and mesenchymal markers such as vimentin and fibronectin. RESULTS: Exposure of HK2 cells to HG (60 mM) activated the expression of vimentin and fibronectin but decreased E-cadherin. Treatment of HK2 cells with SFN caused HG-induced attenuation in EMT markers with activated Nrf2-HO-1. We found that SFN decreased HG-induced production of reactive oxygen species (ROS), phosphorylation of PI3K/Akt at serine 473, and inhibitory phosphorylation of serine/threonine kinase glycogen synthase kinase-3ß (GSK-3ß) at serine 9. Subsequently, these signaling led to the downregulation of the Snail-1 transcriptional factor and the recovery of E-cadherin. CONCLUSION: The present study suggests that Nrf2-HO-1 signaling has an inhibitory role in the regulation of EMT through the modulation of ROS-mediated PI3K/Akt/GSK-3ß activity, highlighting Nrf2-HO-1 and GSK-3ß as potential therapeutic targets in diabetic nephropathy.


Subject(s)
Epithelial-Mesenchymal Transition/drug effects , Glucose/pharmacology , Heme Oxygenase-1/physiology , Kidney Tubules/drug effects , NF-E2-Related Factor 2/physiology , Reactive Oxygen Species/pharmacology , Cells, Cultured , Dose-Response Relationship, Drug , Epithelial-Mesenchymal Transition/genetics , Glycogen Synthase Kinase 3 beta/metabolism , HEK293 Cells , Humans , Kidney Tubules/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Reactive Oxygen Species/metabolism , Signal Transduction/drug effects , Signal Transduction/physiology
9.
Sci Adv ; 4(12): eaat3163, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30539139

ABSTRACT

Thermal emission from objects tends to be spectrally broadband, unpolarized, and temporally invariant. These common notions are now challenged with the emergence of new nanophotonic structures and concepts that afford on-demand, active manipulation of the thermal emission process. This opens a myriad of new applications in chemistry, health care, thermal management, imaging, sensing, and spectroscopy. Here, we theoretically propose and experimentally demonstrate a new approach to actively tailor thermal emission with a reflective, plasmonic metasurface in which the active material and reflector element are epitaxially grown, high-carrier-mobility InAs layers. Electrical gating induces changes in the charge carrier density of the active InAs layer that are translated into large changes in the optical absorption and thermal emission from metasurface. We demonstrate polarization-dependent and electrically controlled emissivity changes of 3.6%P (6.5% in relative scale) in the mid-infrared spectral range.

10.
Nano Lett ; 18(3): 1699-1706, 2018 03 14.
Article in English | MEDLINE | ID: mdl-29356548

ABSTRACT

Explosives, propellants, and pyrotechnics are energetic materials that can store and quickly release tremendous amounts of chemical energy. Aluminum (Al) is a particularly important fuel in many applications because of its high energy density, which can be released in a highly exothermic oxidation process. The diffusive oxidation mechanism (DOM) and melt-dispersion mechanism (MDM) explain the ways powders of Al nanoparticles (NPs) can burn, but little is known about the possible use of plasmonic resonances in NPs to manipulate photoignition. This is complicated by the inhomogeneous nature of powders and very fast heating and burning rates. Here, we generate Al NPs with well-defined sizes, shapes, and spacings by electron beam lithography and demonstrate that their plasmonic resonances can be exploited to heat and ignite them with a laser. By combining simulations with thermal-emission, electron-, and optical-microscopy studies, we reveal how an improved control over NP ignition can be attained.

11.
Nat Commun ; 9(1): 316, 2018 01 22.
Article in English | MEDLINE | ID: mdl-29358626

ABSTRACT

The ability to split an incident light beam into separate wavelength bands is central to a diverse set of optical applications, including imaging, biosensing, communication, photocatalysis, and photovoltaics. Entirely new opportunities are currently emerging with the recently demonstrated possibility to spectrally split light at a subwavelength scale with optical antennas. Unfortunately, such small structures offer limited spectral control and are hard to exploit in optoelectronic devices. Here, we overcome both challenges and demonstrate how within a single-layer metafilm one can laterally sort photons of different wavelengths below the free-space diffraction limit and extract a useful photocurrent. This chipscale demonstration of anti-Hermitian coupling between resonant photodetector elements also facilitates near-unity photon-sorting efficiencies, near-unity absorption, and a narrow spectral response (∼ 30 nm) for the different wavelength channels. This work opens up entirely new design paradigms for image sensors and energy harvesting systems in which the active elements both sort and detect photons.

12.
Mediators Inflamm ; 2017: 8123281, 2017.
Article in English | MEDLINE | ID: mdl-28804222

ABSTRACT

Epithelial-mesenchymal transition (EMT) is a biological process that allows epithelial cells to assume a mesenchymal cell phenotype. EMT is considered as a therapeutic target for several persistent inflammatory airway diseases related to tissue remodeling. Herein, we investigated the role of endoplasmic reticulum (ER) stress and c-Src in TGF-ß1-induced EMT. A549 cells, primary nasal epithelial cells (PNECs), and inferior nasal turbinate organ cultures were exposed to 4-phenylbutylic acid (4PBA) or PP2 and then stimulated with TGF-ß1. We found that E-cadherin, vimentin, fibronectin, and α-SMA expression was increased in nasal polyps compared to inferior turbinates. TGF-ß1 increased the expression of EMT markers such as E-cadherin, fibronectin, vimentin, and α-SMA and ER stress markers (XBP-1s and GRP78), an effect that was blocked by PBA or PP2 treatment. 4-PBA and PP2 also blocked the effect of TGF-ß1 on migration of A549 cells and suppressed TGF-ß1-induced expression of EMT markers in PNECs and organ cultures of inferior turbinate. In conclusion, we demonstrated that 4PBA inhibits TGF-ß1-induced EMT via the c-Src pathway in A549 cells, PNECs, and inferior turbinate organ cultures. These results suggest an important role for ER stress and a diverse role for TGF-ß1 in upper airway chronic inflammatory disease such as CRS.


Subject(s)
Endoplasmic Reticulum Stress/drug effects , Epithelial-Mesenchymal Transition/drug effects , Genes, src/physiology , Transforming Growth Factor beta1/pharmacology , A549 Cells , Cell Movement/drug effects , Endoplasmic Reticulum Chaperone BiP , Genes, src/genetics , Humans , Nasal Polyps/metabolism , Organ Culture Techniques , Signal Transduction/drug effects
13.
Nat Nanotechnol ; 12(9): 866-870, 2017 09.
Article in English | MEDLINE | ID: mdl-28604706

ABSTRACT

Surface plasmon (SP) excitations in metals facilitate confinement of light into deep-subwavelength volumes and can induce strong light-matter interaction. Generally, the SP resonances supported by noble metal nanostructures are explained well by classical models, at least until the nanostructure size is decreased to a few nanometres, approaching the Fermi wavelength λF of the electrons. Although there is a long history of reports on quantum size effects in the plasmonic response of nanometre-sized metal particles, systematic experimental studies have been hindered by inhomogeneous broadening in ensemble measurements, as well as imperfect control over size, shape, faceting, surface reconstructions, contamination, charging effects and surface roughness in single-particle measurements. In particular, observation of the quantum size effect in metallic films and its tuning with thickness has been challenging as they only confine carriers in one direction. Here, we show active tuning of quantum size effects in SP resonances supported by a 20-nm-thick metallic film of indium tin oxide (ITO), a plasmonic material serving as a low-carrier-density Drude metal. An ionic liquid (IL) is used to electrically gate and partially deplete the ITO layer. The experiment shows a controllable and reversible blue-shift in the SP resonance above a critical voltage. A quantum-mechanical model including the quantum size effect reproduces the experimental results, whereas a classical model only predicts a red shift.

14.
Am J Rhinol Allergy ; 31(2): 71-77, 2017 Mar 01.
Article in English | MEDLINE | ID: mdl-28452702

ABSTRACT

PURPOSE: Doxycycline has antibacterial and anti-inflammatory effects, and it also suppresses collagen biosynthesis. This study aimed to confirm the effects and mechanism of doxycycline on transforming growth factor (TGF) beta 1 induced epithelial-mesenchymal transition and cell migration in A549 and primary nasal epithelial cells. METHODS: A 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl-tetrazolium bromide assay and phalloidin-fluorescein isothiocyanate staining were used to evaluate cytotoxicity and cellular morphologic changes. Western blot and immunofluorescence staining were used to determine the expression levels of E-cadherin, vimentin, alpha-smooth muscle actin, fibronectin, phosphorylated Smad2/3, and mitogen-activated protein kinases. Scratch and transwell migration assays were used to assess cellular migration ability. RESULTS: Doxycycline (0-10 µg/mL) had no significant cytotoxic effects in A549 and primary nasal epithelial cells. Increased expression of mesenchymal markers, including vimentin, alpha-smooth muscle actin, and fibronectin in TGF beta 1 induced A549 cells were downregulated by doxycycline treatment. In contrast, E-cadherin expression was upregulated in TGF beta 1 induced A549 cells. An in vitro cell migration assay showed that doxycycline also inhibited the ability of TGF beta 1 induced migration. Doxycycline treatment suppressed the activation of Smad2/3 and p38, whereas its inhibitory effects were similar to each element-specific inhibitor in A549 and primary nasal epithelial cells. CONCLUSION: Doxycycline inhibited TGF beta 1 induced epithelial-to-mesenchymal transition and migration by targeting Smad2/3 and p38 signal pathways in respiratory epithelial cells.


Subject(s)
Antineoplastic Agents/pharmacology , Doxycycline/pharmacology , Epithelial-Mesenchymal Transition/drug effects , Respiratory Mucosa/drug effects , A549 Cells , Cadherins/metabolism , Cell Movement/drug effects , Gene Expression Regulation , Humans , MAP Kinase Signaling System , Primary Cell Culture , Respiratory Mucosa/pathology , Smad2 Protein/metabolism , Smad3 Protein/metabolism , Transforming Growth Factor beta/metabolism , Vimentin/metabolism
15.
Nano Lett ; 17(3): 1892-1898, 2017 03 08.
Article in English | MEDLINE | ID: mdl-28165745

ABSTRACT

Unique features of graphene have motivated the development of graphene-integrated photonic devices. In particular, the electrical tunability of graphene loss enables high-speed modulation of light and tuning of cavity resonances in graphene-integrated waveguides and cavities. However, efficient control of light emission such as lasing, using graphene, remains a challenge. In this work, we demonstrate on/off switching of single- and double-cavity photonic crystal lasers by electrical gating of a monolayer graphene sheet on top of photonic crystal cavities. The optical loss of graphene was controlled by varying the gate voltage Vg, with the ion gel atop the graphene sheet. First, the fundamental properties of graphene were investigated through the transmittance measurement and numerical simulations. Next, optically pumped lasing was demonstrated for a graphene-integrated single photonic crystal cavity at Vg below -0.6 V, exhibiting a low lasing threshold of ∼480 µW, whereas lasing was not observed at Vg above -0.6 V owing to the intrinsic optical loss of graphene. Changing quality factor of the graphene-integrated photonic crystal cavity enables or disables the lasing operation. Moreover, in the double-cavity photonic crystal lasers with graphene, switching of individual cavities with separate graphene sheets was achieved, and these two lasing actions were controlled independently despite the close distance of ∼2.2 µm between adjacent cavities. We believe that our simple and practical approach for switching in graphene-integrated active photonic devices will pave the way toward designing high-contrast and ultracompact photonic integrated circuits.

16.
Nano Lett ; 17(1): 407-413, 2017 01 11.
Article in English | MEDLINE | ID: mdl-27936784

ABSTRACT

Optical metasurfaces are two-dimensional optical elements composed of dense arrays of subwavelength optical antennas and afford on-demand manipulation of the basic properties of light waves. Following the pioneering works on active metasurfaces capable of modulating wave amplitude, there is now a growing interest to dynamically control other fundamental properties of light. Here, we present metasurfaces that facilitate electrical tuning of the reflection phase and polarization properties. To realize these devices, we leverage the properties of actively controlled plasmonic antennas and fundamental insights provided by coupled mode theory. Indium-tin-oxide is embedded into gap-plasmon resonator-antennas as it offers electrically tunable optical properties. By judiciously controlling the resonant properties of the antennas from under- to overcoupling regimes, we experimentally demonstrate tuning of the reflection phase over 180°. This work opens up new design strategies for active metasurfaces for displacement measurements and tunable waveplates.

17.
Korean J Pediatr ; 59(Suppl 1): S125-S128, 2016 Nov.
Article in English | MEDLINE | ID: mdl-28018464

ABSTRACT

Harlequin syndrome, which is a rare disorder caused by dysfunction of the autonomic system, manifests as asymmetric facial flushing and sweating in response to heat, exercise, or emotional factors. The syndrome may be primary (idiopathic) with a benign course, or can occur secondary to structural abnormalities or iatrogenic factors. The precise mechanism underlying idiopathic harlequin syndrome remains unclear. Here, we describe a case of a 6-year-old boy who reported left hemifacial flushing and sweating after exercise. He had an unremarkable birth history and no significant medical history. Complete ophthalmological and neurological examinations were performed, and no other abnormalities were identified. Magnetic resonance imaging was performed to exclude lesions of the cerebrum and cervicothoracic spinal cord, and no abnormalities were noted. His final diagnosis was classic idiopathic harlequin syndrome. Herein, we report the first pediatric case of idiopathic harlequin syndrome in Korea.

18.
PLoS One ; 11(12): e0168195, 2016.
Article in English | MEDLINE | ID: mdl-28002421

ABSTRACT

PURPOSE: Baicalin, a Chinese herbal medicine, has anti-fibrotic and anti-inflammatory effects. The aims of present study were to investigate the effects of baicalin on the myofibroblast differentiation, extracellular matrix production, migration, and collagen contraction of interleukin (IL)-1ß-stimulated nasal fibroblasts and to determine the molecular mechanism of baicalin in nasal fibroblasts. METHODS: Nasal fibroblasts were isolated from the inferior turbinate of patients. Baicalin was used to treat IL-1ß-stimulated nasal fibroblasts. To evaluate cytotoxicity, a 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyl-tetrazolium bromide assay was used. The expression levels of α-smooth muscle actin (SMA), fibronectin, phospho-mitogen-activated protein kinase (p-MAPK), p-Akt, p-p50, p-p65, and p-IκBα were measured by western blotting, reverse transcription-polymerase chain reaction (RT-PCR),or immunofluorescence staining. Fibroblast migration was analyzed with scratch assays and transwell migration assays. Total collagen was evaluated with the Sircol collagen assay. Contractile activity was measured with a collagen gel contraction assay. RESULTS: Baicalin (0-50 µM) had no significant cytotoxic effects in nasal fibroblasts. The expression of α-SMA and fibronectin were significantly down-regulated in baicalin-treated nasal fibroblasts. Migration, collagen production, and contraction of IL-1ß-stimulated nasal fibroblasts were significantly inhibited by baicalin treatment. Baicalin also significantly down-regulated p-MAPK, p-Akt, p-p50, p-p65, and p-IκBα in IL-1ß-stimulated nasal fibroblasts. CONCLUSIONS: We showed that baicalin down-regulated myofibroblast differentiation, extracellular matrix production, migration, and collagen contraction via the MAPK and Akt/ NF-κB pathways in IL-1ß-stimulated nasal fibroblasts.


Subject(s)
Down-Regulation/drug effects , Extracellular Matrix/metabolism , Fibroblasts/drug effects , Flavonoids/pharmacology , Actins/genetics , Actins/metabolism , Adult , Cell Differentiation/drug effects , Cell Movement/drug effects , Cells, Cultured , Collagen/metabolism , Female , Fibroblasts/cytology , Fibroblasts/metabolism , Fibronectins/metabolism , Gene Expression/drug effects , Humans , Interleukin-1beta/pharmacology , Male , Matrix Metalloproteinase 1/genetics , Matrix Metalloproteinase 1/metabolism , Mitogen-Activated Protein Kinases/metabolism , NF-kappa B/antagonists & inhibitors , NF-kappa B/metabolism , Nasal Cavity/cytology , Nitriles/pharmacology , Proto-Oncogene Proteins c-akt/metabolism , Sulfones/pharmacology
19.
Nephron ; 134(4): 272-282, 2016.
Article in English | MEDLINE | ID: mdl-27560625

ABSTRACT

BACKGROUND: Renin, in addition to its activation of the renin-angiotensin system, binds to the (pro)renin receptor (PRR) and triggers inflammatory and fibrogenic signaling in tissue. In addition, aliskiren, a direct renin inhibitor, has been shown to affect IgG metabolism by altering PRR and neonatal Fc receptors (FcRns). METHODS: We investigated the effect of aliskiren on proteinuria, glomerular extracellular matrix, expressions of fibronectin, transforming growth factor ß1 (TGF-ß1), PRR, FcRn and renal metabolism of IgG in a mice model of anti-glomerular basement membrane glomerulonephritis (anti-GBM GN). RESULTS: IgG deposition and expressions of FcRn and PRR were enhanced at glomeruli and urinary IgG levels increased in anti-GBM GN. Aliskiren attenuated anti-GBM GN with reduction of proteinuria and cortical expressions of fibronectin and TGF-ß1. In addition, aliskiren suppressed the renal cortical expressions of FcRn and PRR. Aliskiren also reduced the glomerular IgG depositions and the urinary IgG levels albeit with increased circulating serum IgG levels. CONCLUSION: These results suggest that suppression of FcRn and PRR and regulation of IgG metabolism may be related to the attenuation of anti-GBM GN by aliskiren.


Subject(s)
Amides/pharmacology , Anti-Glomerular Basement Membrane Disease/drug therapy , Anti-Glomerular Basement Membrane Disease/immunology , Fumarates/pharmacology , Histocompatibility Antigens Class I/metabolism , Immunoglobulin G/metabolism , Receptors, Fc/metabolism , Animals , Anti-Glomerular Basement Membrane Disease/metabolism , Immunoglobulin G/blood , Immunoglobulin G/urine , Kidney Cortex/drug effects , Kidney Cortex/metabolism , Male , Mice , Mice, Inbred BALB C , Rabbits , Receptors, Cell Surface/metabolism , Renin/antagonists & inhibitors , Renin-Angiotensin System/drug effects , Transforming Growth Factor beta1/metabolism , Prorenin Receptor
20.
PLoS One ; 11(8): e0162058, 2016.
Article in English | MEDLINE | ID: mdl-27571418

ABSTRACT

BACKGROUND AND OBJECTIVES: Tissue remodeling is believed to cause recalcitrant chronic rhinosinusitis (CRS). Epithelial-mesenchymal transition (EMT) is a novel clinical therapeutic target in many chronic airway diseases related with tissue remodeling. The aim of this study was to investigate the effect of trichostatin A (TSA) on transforming growth factor (TGF)-ß1-induced EMT in airway epithelium and nasal tissue. MATERIALS AND METHODS: A549 cells, primary nasal epithelial cells (PNECs), or inferior nasal turbinate organ culture were exposed to TSA prior to stimulation with TGF-ß1. Expression levels of E-cadherin, vimentin, fibronectin, α-smooth muscle actin (SMA), histone deacetylase 2 (HDAC2), and HDAC4 were determined by western blotting and/or immunofluorescent staining. Hyperacetylation of histone H2 and H4 by TSA was measured by western blotting. After siHDAC transfection, the effects of HDAC2 and HDAC4 silencing on expression of E-cadherin, vimentin, fibronectin, α-SMA, HDAC2, and HDAC4 in TGF-ß1-induced A549 were determined by RT-PCR and/or western blotting. We assessed the change in migration capacity of A549 cells by using cell migration assay and transwell invasion assay. RESULTS: TGF-ß1 altered mRNA and protein expression levels of EMT markers including E-cadherin, vimentin, fibronectin, α-SMA, slug, and snail in A549 cells. Inhibition and silencing of HDAC2 and HDAC4 by TSA and siRNA enhanced TGF-ß1-induced EMT in A549 cells. TSA blocked the effect of TGF-ß1 on the migratory ability of A549 cells. In experiments using PNECs and inferior turbinate organ cultures, TSA suppressed expression of EMT markers induced by TGF-ß1. CONCLUSIONS: We showed that EMT is induced by TGF-ß1 in airway epithelial cells and nasal tissue via activation of HDAC2 and HDAC4, and that inhibition of HDAC2 and HDAC4 by TSA reduces TGF-ß1-induced EMT. This observation indicates that histone deacetylase inhibitors such as TSA could be potential candidates for treatment of recalcitrant CRS related with tissue remodeling.


Subject(s)
Epithelial-Mesenchymal Transition/drug effects , Hydroxamic Acids/pharmacology , Transforming Growth Factor beta1/pharmacology , A549 Cells , Cadherins/genetics , Cadherins/metabolism , Cells, Cultured , Epithelial-Mesenchymal Transition/genetics , Fibronectins/genetics , Fibronectins/metabolism , Histone Deacetylase 2/genetics , Histone Deacetylase 2/metabolism , Histone Deacetylases/genetics , Histone Deacetylases/metabolism , Humans , Organ Culture Techniques , RNA, Messenger , Repressor Proteins/genetics , Repressor Proteins/metabolism , Snail Family Transcription Factors/genetics , Snail Family Transcription Factors/metabolism , Vimentin/genetics , Vimentin/metabolism
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