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1.
Nat Immunol ; 17(11): 1252-1262, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27595231

RESUMEN

The mammalian cytoplasmic multi-tRNA synthetase complex (MSC) is a depot system that regulates non-translational cellular functions. Here we found that the MSC component glutamyl-prolyl-tRNA synthetase (EPRS) switched its function following viral infection and exhibited potent antiviral activity. Infection-specific phosphorylation of EPRS at Ser990 induced its dissociation from the MSC, after which it was guided to the antiviral signaling pathway, where it interacted with PCBP2, a negative regulator of mitochondrial antiviral signaling protein (MAVS) that is critical for antiviral immunity. This interaction blocked PCBP2-mediated ubiquitination of MAVS and ultimately suppressed viral replication. EPRS-haploid (Eprs+/-) mice showed enhanced viremia and inflammation and delayed viral clearance. This stimulus-inducible activation of MAVS by EPRS suggests an unexpected role for the MSC as a regulator of immune responses to viral infection.


Asunto(s)
Aminoacil-ARNt Sintetasas/metabolismo , Resistencia a la Enfermedad/inmunología , Interacciones Huésped-Patógeno/inmunología , Virosis/inmunología , Virosis/metabolismo , Aminoacil-ARNt Sintetasas/química , Aminoacil-ARNt Sintetasas/genética , Animales , Antivirales/farmacología , Modelos Animales de Enfermedad , Inmunidad Innata , Ratones , Ratones Noqueados , Péptidos/farmacología , Fosforilación , Unión Proteica , Infecciones por Virus ARN/inmunología , Infecciones por Virus ARN/metabolismo , Infecciones por Virus ARN/virología , Virus ARN/efectos de los fármacos , Virus ARN/inmunología , Proteínas de Unión al ARN/metabolismo , Transducción de Señal , Ubiquitinación , Virosis/virología , Replicación Viral
2.
J Allergy Clin Immunol ; 153(6): 1711-1720, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38520423

RESUMEN

BACKGROUND: There is growing evidence that the coronavirus disease 2019 (COVID-19) vaccination can affect the regulation of the immune system, leading to the development of autoimmune diseases. However, the autoimmune adverse events (AEs) after COVID-19 vaccination remain largely unclear. OBJECTIVE: We sought to investigate the autoimmune AEs after COVID-19 vaccination from a population-based cohort in South Korea. METHODS: A total of 4,203,887 participants, representing 50% of the population residing in Seoul, were recruited from the National Health Insurance Service database and then divided into 2 groups on the basis of COVID-19 vaccination. The cumulative incidence, hazard ratios (HRs), and 95% CIs of autoimmune AEs were assessed following COVID-19 vaccination. RESULTS: The incidence of vitiligo has been observed to be significantly higher in the vaccination group compared with the no vaccination group. The cumulative incidence of vitiligo began to show a significant difference starting 2 weeks after vaccination, and it reached 2.2% in the vaccination group and 0.6% in the no vaccination group by 3 months after COVID-19 vaccination. Vitiligo (HR, 2.714; 95% CI, 1.777-4.146) was an increased risk among autoimmune AEs. Furthermore, the risk of vitiligo was the highest for heterologous vaccination (HR, 3.890; 95% CI, 2.303-6.573) compared with using cDNA vaccine (HR, 2.861; 95% CI, 1.838-4.453) or mRNA vaccine (HR, 2.475; 95% CI, 1.607-3.813). CONCLUSIONS: Vitiligo as an autoimmune AE was noted to be substantially higher in the COVID-19-vaccinated group compared with the controls. Therefore, the occurrence of vitiligo could be considered as one of the significant AEs post-COVID-19 vaccination.


Asunto(s)
Enfermedades Autoinmunes , Vacunas contra la COVID-19 , COVID-19 , Vitíligo , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Autoinmunes/inducido químicamente , COVID-19/prevención & control , Vacunas contra la COVID-19/efectos adversos , Incidencia , República de Corea/epidemiología , Seúl/epidemiología , Vacunación/efectos adversos , Vitíligo/inducido químicamente
3.
Korean J Physiol Pharmacol ; 28(1): 83-91, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38154967

RESUMEN

Hypoxia-inducible factor-1 alpha (HIF-1α) is a transcription factor activated under hypoxic conditions, and it plays a crucial role in cellular stress regulation. While HIF-1α activity is essential in normal tissues, its presence in the tumor microenvironment represents a significant risk factor as it can induce angiogenesis and confer resistance to anti-cancer drugs, thereby contributing to poor prognoses. Typically, HIF-1α undergoes rapid degradation in normoxic conditions via oxygen-dependent degradation mechanisms. However, certain cancer cells can express HIF-1α even under normoxia. In this study, we observed an inclination toward increased normoxic HIF-1α expression in cancer cell lines exhibiting increased HDAC6 expression, which prompted the hypothesis that HDAC6 may modulate HIF-1α stability in normoxic conditions. To prove this hypothesis, several cancer cells with relatively higher HIF-1α levels under normoxic conditions were treated with ACY-241, a selective HDAC6 inhibitor, and small interfering RNAs for HDAC6 knockdown. Our data revealed a significant reduction in HIF-1α expression upon HDAC6 inhibition. Moreover, the downregulation of HIF-1α under normoxic conditions decreased zinc finger E-box-binding homeobox 1 expression and increased E-cadherin levels in lung cancer H1975 cells, consequently suppressing cell invasion and migration. ACY-241 treatment also demonstrated an inhibitory effect on cell invasion and migration by reducing HIF-1α level. This study confirms that HDAC6 knockdown and ACY-241 treatment effectively decrease HIF-1α expression under normoxia, thereby suppressing the epithelial-mesenchymal transition. These findings highlight the potential of selective HDAC6 inhibition as an innovative therapeutic strategy for lung cancer.

4.
Proc Natl Acad Sci U S A ; 116(33): 16256-16261, 2019 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-31366630

RESUMEN

Complex liquids flow through channels faster than expected, an effect attributed to the formation of low-viscosity depletion layers at the boundaries. Characterization of depletion layer length scale, concentration, and dynamics has remained elusive due in large part to the lack of suitable real-space experimental techniques. The short length scales associated with depletion layers have traditionally prohibited direct imaging. By overcoming this limitation via adaptations of stimulated emission depletion (STED) microscopy, we directly measure the concentration profile of polymer solutions at a nonadsorbing wall under Poiseuille flow. Using this approach, we 1) confirm the theoretically predicted concentration profile governed by entropically driven depletion, 2) observe depletion layer narrowing at low to intermediate shear rates, and 3) report depletion layer composition that approaches pure solvent at unexpectedly low shear rates.

5.
Proc Natl Acad Sci U S A ; 116(26): 12733-12742, 2019 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-31175151

RESUMEN

Thermal motion in complex fluids is a complicated stochastic process but ubiquitously exhibits initial ballistic, intermediate subdiffusive, and long-time diffusive motion, unless interrupted. Despite its relevance to numerous dynamical processes of interest in modern science, a unified, quantitative understanding of thermal motion in complex fluids remains a challenging problem. Here, we present a transport equation and its solutions, which yield a unified quantitative explanation of the mean-square displacement (MSD), the non-Gaussian parameter (NGP), and the displacement distribution of complex fluids. In our approach, the environment-coupled diffusion kernel and its time correlation function (TCF) are the essential quantities that determine transport dynamics and characterize mobility fluctuation of complex fluids; their time profiles are directly extractable from a model-free analysis of the MSD and NGP or, with greater computational expense, from the two-point and four-point velocity autocorrelation functions. We construct a general, explicit model of the diffusion kernel, comprising one unbound-mode and multiple bound-mode components, which provides an excellent approximate description of transport dynamics of various complex fluidic systems such as supercooled water, colloidal beads diffusing on lipid tubes, and dense hard disk fluid. We also introduce the concepts of intrinsic disorder and extrinsic disorder that have distinct effects on transport dynamics and different dependencies on temperature and density. This work presents an unexplored direction for quantitative understanding of transport and transport-coupled processes in complex disordered media.

6.
Phys Rev Lett ; 126(12): 126001, 2021 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-33834800

RESUMEN

Catalytic reaction events occurring on the surface of a nanoparticle constitute a complex stochastic process. Although advances in modern single-molecule experiments enable direct measurements of individual catalytic turnover events occurring on a segment of a single nanoparticle, we do not yet know how to measure the number of catalytic sites in each segment or how the catalytic turnover counting statistics and the catalytic turnover time distribution are related to the microscopic dynamics of catalytic reactions. Here, we address these issues by presenting a stochastic kinetics for nanoparticle catalytic systems. We propose a new experimental measure of the number of catalytic sites in terms of the mean and variance of the catalytic event count. By considering three types of nanocatalytic systems, we investigate how the mean, the variance, and the distribution of the catalytic turnover time depend on the catalytic reaction dynamics, the heterogeneity of catalytic activity, and communication among catalytic sites. This work enables accurate quantitative analyses of single-molecule experiments for nanocatalytic systems and enzymes with multiple catalytic sites.

7.
Sensors (Basel) ; 21(6)2021 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-33801968

RESUMEN

Field-effect transistor (FET)-based biosensors have garnered significant attention for their label-free electrical detection of charged biomolecules. Whereas conventional output parameters such as threshold voltage and channel current have been widely used for the detection and quantitation of analytes of interest, they require bulky instruments and specialized readout circuits, which often limit point-of-care testing applications. In this study, we demonstrate a simple conversion method that transforms the surface potential into an oscillating signal as an output of the FET-based biosensor. The oscillation frequency is proposed as a parameter for FET-based biosensors owing to its intrinsic advantages of simple and compact implementation of readout circuits as well as high compatibility with neuromorphic applications. An extended-gate biosensor comprising an Al2O3-deposited sensing electrode and a readout transistor is connected to a ring oscillator that generates surface potential-controlled oscillation for pH sensing. Electrical measurement of the oscillation frequency as a function of pH reveals that the oscillation frequency can be used as a sensitive and reliable output parameter in FET-based biosensors for the detection of chemical and biological species. We confirmed that the oscillation frequency is directly correlated with the threshold voltage. For signal amplification, the effects of circuit parameters on pH sensitivity are investigated using different methods, including electrical measurements, analytical calculations, and circuit simulations. An Arduino board to measure the oscillation frequency is integrated with the proposed sensor to enable portable and real-time pH measurement for point-of-care testing applications.


Asunto(s)
Técnicas Biosensibles , Electrodos , Transistores Electrónicos
8.
Sensors (Basel) ; 21(7)2021 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-33806160

RESUMEN

This study proposes a soft inductive coil spring (SICS) strain sensor that can measure the strain of soft actuators. The SICS sensor, produced by transforming a shape memory alloy (SMA) wire with the same materials as that of an SMA spring bundle actuator (SSBA) into a coil spring shape, measures inductance changes according to length changes. This study also proposes a manufacturing method, output characteristics of the SICS sensor applicable to the SSBA among soft actuators, and the structure of the SICS sensor-integrated SSBA (SI-SSBA). In the SI-SSBA, the SMA spring bundle and SICS sensor have structures corresponding to the muscle fiber and spindle of the skeletal muscle, respectively. It is demonstrated that when a robotic arm with one degree of freedom is operated by attaching two SI-SSBAs in an antagonistic structure, the displacement of the SSBA can be measured using the proposed strain sensor. The output characteristics of the SICS sensor for the driving speed of the robotic arm were evaluated, and it was experimentally proven that the strain of the SSBA can be stably measured in water under a temperature change of 54 °C from 36 to 90 °C.

9.
Sensors (Basel) ; 21(8)2021 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-33919929

RESUMEN

In the field of robotics, sensors are crucial in enabling the interaction between robots and their users. To ensure this interaction, sensors mainly measure the user's strength, and based on this, wearable robots are controlled. In this paper, we propose a novel three-axis force/torque sensor for wearable robots that is compact and has a high load capacity. The bolt and nut combination of the proposed sensor is designed to measure high-load weights, and the simple structure of this combination allows the sensor to be compact and light. Additionally, to measure the three-axis force/torque, we design three capacitance-sensing cells. These cells are arranged in parallel to measure the difference in capacitance between the positive and negative electrodes. From the capacitance change measured by these sensing cells, force/torque information is converted through deep neural network calibration. The sensing point can also be confirmed using the geometric and kinematic relation of the sensor. The proposed sensor is manufactured through a simple and inexpensive process using cheap and simply structured components. The performance of the sensor, such as its repeatability and capacity, is evaluated using several experimental setups. In addition, the sensor is applied to a wearable robot to measure the force of an artificial muscle.


Asunto(s)
Robótica , Dispositivos Electrónicos Vestibles , Capacidad Eléctrica , Torque
10.
Sensors (Basel) ; 21(24)2021 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-34960590

RESUMEN

Cytokines are proteins secreted by immune cells. They promote cell signal transduction and are involved in cell replication, death, and recovery. Cytokines are immune modulators, but their excessive secretion causes uncontrolled inflammation that attacks normal cells. Considering the properties of cytokines, monitoring the secretion of cytokines in vivo is of great value for medical and biological research. In this review, we offer a report on recent studies for cytokine detection, especially studies on aptasensors using aptamers. Aptamers are single strand nucleic acids that form a stable three-dimensional structure and have been receiving attention due to various characteristics such as simple production methods, low molecular weight, and ease of modification while performing a physiological role similar to antibodies.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Citocinas
11.
Medicina (Kaunas) ; 57(6)2021 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-34208279

RESUMEN

The aim of the present study was to report two cases of refractory dry eye syndrome (DES) after transconjunctival excision of the palpebral lobe of the lacrimal gland. A 25-year-old female patient with a chief complaint of a palpable mass in both upper eyelids visited our medical center. Preoperative orbital computer tomography showed high-attenuation lesions in both lacrimal glands. Incisional biopsy of the lacrimal gland palpebral lobe via transconjunctival incision was performed in January 2019. At 1 month after the biopsy, a lack of tears and persistent corneal erosions were found in both eyes. Artificial tears, punctal occlusion, autologous serum eye drops, and therapeutic contact lenses were applied in an attempt to control the dry eye symptoms. The patient continues to suffer from intractable DES at 2.5 years after the procedure. The second case involved a 52-year-old female patient who visited our medical center with a chief complaint of a palpable mass in both upper eyelids. Bilateral orbital tumors were diagnosed with preoperative magnetic resonance imaging. An incisional biopsy of the lacrimal gland was performed. Immunoglobulin G4-related dacryoadenitis was confirmed through lacrimal palpebral lobe incisional biopsy. Intractable DES and corneal erosion of her left eye persisted thereafter. A transconjunctival incision is an effective approach for minimizing postoperative scars and is suitable for the biopsy of tumors that are visible through the conjunctiva. After a biopsy of the palpebral lobe of the main lacrimal glands, the secretion of reflex tears decreases due to damage to the secreting ducts of the main lacrimal glands. However, total tear secretion can be maintained by basal tear secretion from the accessory lacrimal glands. In this report, we describe two cases of refractory DES due to decreased total tear secretion, although only the palpebral lobes of the main lacrimal glands were biopsied.


Asunto(s)
Síndromes de Ojo Seco , Aparato Lagrimal , Adulto , Conjuntiva/cirugía , Síndromes de Ojo Seco/etiología , Síndromes de Ojo Seco/cirugía , Párpados , Femenino , Humanos , Aparato Lagrimal/diagnóstico por imagen , Aparato Lagrimal/cirugía , Persona de Mediana Edad , Lágrimas
12.
PLoS Comput Biol ; 15(9): e1007356, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31525182

RESUMEN

Even in the steady-state, the number of biomolecules in living cells fluctuates dynamically, and the frequency spectrum of this chemical fluctuation carries valuable information about the dynamics of the reactions creating these biomolecules. Recent advances in single-cell techniques enable direct monitoring of the time-traces of the protein number in each cell; however, it is not yet clear how the stochastic dynamics of these time-traces is related to the reaction mechanism and dynamics. Here, we derive a rigorous relation between the frequency-spectrum of the product number fluctuation and the reaction mechanism and dynamics, starting from a generalized master equation. This relation enables us to analyze the time-traces of the protein number and extract information about dynamics of mRNA number and transcriptional regulation, which cannot be directly observed by current experimental techniques. We demonstrate our frequency spectrum analysis of protein number fluctuation, using the gene network model of luciferase expression under the control of the Bmal 1a promoter in mouse fibroblast cells. We also discuss how the dynamic heterogeneity of transcription and translation rates affects the frequency-spectra of the mRNA and protein number.


Asunto(s)
Biología Computacional/métodos , Redes Reguladoras de Genes , Modelos Biológicos , Animales , Línea Celular , Simulación por Computador , Redes Reguladoras de Genes/genética , Redes Reguladoras de Genes/fisiología , Ratones , Proteínas/análisis , Proteínas/genética , Proteínas/metabolismo , ARN Mensajero/análisis , ARN Mensajero/genética , ARN Mensajero/metabolismo , Análisis de la Célula Individual , Procesos Estocásticos
13.
Molecules ; 25(23)2020 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-33255851

RESUMEN

Herein, we describe novel pentafluorosulfanyl (SF5) group-containing meta-diamide insecticides. For the facile preparation of the SF5-based compounds 4a-d, practical synthetic methods were applied. Among newly synthesized compounds, 3-benzamido-N-(2,6-dimethyl-4-(pentafluoro-λ6-sulfanyl)phenyl)-2-fluorobenzamide 4d showed (i) a high insecticidal activity, (ii) an excellent selectivity to insects, and (iii) good levels of water solubility and log P values. In this study, we demonstrated that the pentafluorosulfanyl moiety could serve as an attractive functionality for the discovery of a new scope of crop-protecting agents.


Asunto(s)
Técnicas de Química Sintética , Diamida/síntesis química , Diamida/farmacología , Insecticidas/síntesis química , Insecticidas/farmacología , Metales/química , Antagonistas del GABA/química , Antagonistas del GABA/farmacología , Estructura Molecular , Receptores de GABA/química , Relación Estructura-Actividad
14.
J Proteome Res ; 18(10): 3800-3806, 2019 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-31475827

RESUMEN

We propose to use cRFP (common Repository of FBS Proteins) in the MS (mass spectrometry) raw data search of cell secretomes. cRFP is a small supplementary sequence list of highly abundant fetal bovine serum proteins added to the reference database in use. The aim behind using cRFP is to prevent the contaminant FBS proteins from being misidentified as other proteins in the reference database, just as we would use cRAP (common Repository of Adventitious Proteins) to prevent contaminant proteins present either by accident or through unavoidable contacts from being misidentified as other proteins. We expect it to be widely used in experiments where the proteins are obtained from serum-free media after thorough washing of the cells, or from a complex media such as SILAC, or from extracellular vesicles directly.


Asunto(s)
Células Cultivadas/metabolismo , Proteoma/análisis , Proteómica/métodos , Suero/química , Animales , Bovinos , Medios de Cultivo/química , Bases de Datos de Proteínas , Humanos , Espectrometría de Masas
15.
Lasers Med Sci ; 34(3): 571-581, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30244402

RESUMEN

To investigate the role of Wnt/ß-catenin signaling pathway in the restoration of induced pluripotent stem cell-derived retinal pigment epithelium (hiPSC-RPE) after laser photocoagulation. After differentiation of RPE cells from hiPSCs, laser photocoagulation was performed. Activation of Wnt/ß-catenin signaling at days 1 and 5 after laser photocoagulation was evaluated by expression of ß-catenin. Cell proliferation and alteration in cell-to-cell contact at day 5 after laser photocoagulation with or without Dickkopf-1 (Dkk-1) treatment were studied using ethynyl-2'-deoxyuridine (EdU) assay and zonula occludens-1 (ZO-1) expression analysis, respectively. The mRNA levels of Wnt genes at day 5 after laser photocoagulation were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR). Activation of Wnt/ß-catenin signaling at days 1 and 5 after laser photocoagulation was confirmed by ß-catenin accumulation in the cytoplasm and nucleus of hiPSC-RPE. Many EdU-positive cells also expressed ß-catenin, and the number of EdU-positive cells was decreased at day 5 after laser photocoagulation after Dkk-1 treatment, indicating that Wnt/ß-catenin signaling mediated hiPSC-RPE proliferation. ZO-1 expression was not decreased with Dkk-1 treatment at day 5 after laser photocoagulation, indicating that Wnt/ß-catenin signaling mediated hiPSC-RPE restoration. At day 5, after laser photocoagulation, mRNA levels of Wnt2b, Wnt3, Wnt5a, Wnt7a, and Wnt10b were increased. Wnt/ß-catenin signaling has a crucial role in restoration of hiPSC-RPE proliferation after laser photocoagulation. Manipulation of Wnt/ß-catenin signaling while elucidating the underlying mechanisms of RPE restoration might have a therapeutic potential in retinal degenerative diseases.


Asunto(s)
Células Madre Pluripotentes Inducidas/citología , Coagulación con Láser , Epitelio Pigmentado de la Retina/citología , Epitelio Pigmentado de la Retina/efectos de la radiación , Vía de Señalización Wnt , Diferenciación Celular/efectos de la radiación , Proliferación Celular/efectos de la radiación , Forma de la Célula/efectos de la radiación , Fluorescencia , Regulación de la Expresión Génica/efectos de la radiación , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Células Madre Pluripotentes Inducidas/efectos de la radiación , Péptidos y Proteínas de Señalización Intercelular/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Epitelio Pigmentado de la Retina/metabolismo , Factores de Tiempo , Vía de Señalización Wnt/genética , Vía de Señalización Wnt/efectos de la radiación , Proteína de la Zonula Occludens-1/metabolismo , beta Catenina/metabolismo
16.
Molecules ; 24(19)2019 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-31547559

RESUMEN

Novel anthranilic diamides with sulfilimidoyl and sulfoximidoyl functionalities were successfully prepared. Among newly-prepared organosulfur compounds, 3-bromo-1-(3-chloropyridin-2-yl)-N-(2-methyl-6-(methylcarbamoyl)-4-(methylthio)phenyl)-1H-pyrazole-5-carboxamide and (S,E)-3-bromo-1-(3-chloropyridin-2-yl)-N-(2-methyl-4-(S-methyl-N-(2,2,2-trifluoroacetyl)sulfinimidoyl)-6-(methylcarbamoyl)phenyl)-1H-pyrazole-5-carboxamide showed good levels of efficacy and a strong correlation between insecticidal activities and physical properties, respectively. In particular, available data indicated that the N-trifluoroacetyl sulfilimine moiety could be an appealing structural scaffold for the discovery of a new crop-protecting agent.


Asunto(s)
Antivirales/síntesis química , Diamida/química , Isoxazoles/química , Animales , Antivirales/farmacología , Cromatografía en Capa Delgada , Insecticidas/síntesis química , Insecticidas/farmacología , Spodoptera/efectos de los fármacos , Relación Estructura-Actividad
17.
EMBO Rep ; 17(1): 64-78, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26598551

RESUMEN

LATS1/2 (large tumor suppressor) kinases and the Angiomotin family proteins are potent inhibitors of the YAP (yes-associated protein) oncoprotein, but the underlying molecular mechanism is not fully understood. Here, we report for the first time that USP9X is a deubiquitinase of Angiomotin-like 2 (AMOTL2) and that AMOTL2 mono-ubiquitination is required for YAP inhibition. USP9X knockdown increased the LATS-mediated phosphorylation of YAP and decreased the transcriptional output of YAP. Conversely, over-expression of USP9X reactivated YAP in densely cultured cells. Both genetic and biochemical approaches identified AMOTL2 as a target of USP9X. AMOTL2 was found to be ubiquitinated at K347 and K408, which both reside in the protein's coiled-coil domain. The AMOTL2 K347/408R mutant, which cannot be ubiquitinated, was impaired in its ability to inhibit YAP. Furthermore, ubiquitinated AMOTL2 can bind to the UBA domain of LATS kinase, and this domain is required for the function of LATS. Our results provide novel insights into the activation mechanisms of core Hippo pathway components.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Proteínas de la Membrana/metabolismo , Fosfoproteínas/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Angiomotinas , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Células HEK293 , Humanos , Péptidos y Proteínas de Señalización Intercelular/genética , Proteínas de la Membrana/genética , Proteínas de Microfilamentos , Proteínas Oncogénicas/genética , Proteínas Oncogénicas/metabolismo , Fosfoproteínas/metabolismo , Fosforilación , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal/genética , Factores de Transcripción , Proteínas Supresoras de Tumor/metabolismo , Ubiquitina Tiolesterasa/genética , Ubiquitinación , Proteínas Señalizadoras YAP
18.
BMC Ophthalmol ; 18(1): 70, 2018 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-29506497

RESUMEN

BACKGROUND: We developed a novel surgical technique to treat punctal stenosis involving the placement of three interrupted sutures after rectangular three-snip punctoplasty (TSP). METHODS: Retrospective chart review of forty-eight eyes of 44 patients who underwent rectangular TSP with three interrupted sutures was performed. We investigated whether anatomical recurrences (re-stenosis) occurred during the follow-up period. The subjective symptoms of patients were surveyed. RESULTS: The mean patient age was 64.1 years, and the mean follow-up time was 17.4 months. The placement of three interrupted sutures after rectangular TSP afforded satisfactory outcomes. Regarding subjective symptoms, 91.7% of the eyes (44/48) were reported as improved. Among 4 eyes determined as symptomatic failure, anatomical recurrence (re-stenosis of the punctum) was observed in only one eye. The other three (6.25%, 3/48 eyes) showed functional nasolacrimal obstruction, namely epiphora with patent tear duct. CONCLUSIONS: Placement of three interrupted sutures after rectangular TSP to treat punctal stenosis showed promising results. Notably anatomical success rate was about 98%. Further comparisons between the novel surgical technique and conventional techniques are required.


Asunto(s)
Enfermedades de los Párpados/cirugía , Aparato Lagrimal/cirugía , Obstrucción del Conducto Lagrimal/terapia , Procedimientos Quirúrgicos Oftalmológicos , Técnicas de Sutura , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Nylons , Estudios Retrospectivos , Suturas
19.
Ophthalmic Plast Reconstr Surg ; 34(6): 547-551, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29634605

RESUMEN

PURPOSE: To determine the relationship between the distribution of adrenergic receptors in the human eyelid and the eyelid elevation after topically instilling 0.5% apraclonidine in blepharoptosis patients. METHODS: A total of 26 blepharoptotic patients (30 eyelids) were included in the experimental study. Marginal reflex distance 1 was measured before and after topical instillation of 0.5% apraclonidine. Eyelids were divided into 2 groups according to the responses to topical 0.5% apraclonidine. Patients who positively responded to apraclonidine were classified as group A and those that negatively responded to it were classified as group B. Müller's muscle was obtained during the blepharoptotic surgery, followed by immunohistochemical staining and scoring. This study was approved by the Institutional Review Board of Kim's Eye Hospital and the study protocol adhered to the tenets of the Declaration of Helsinki. RESULTS: α-1D staining intensity was significantly higher in group A than in B (p < 0.001) and α-2C and ß-1 staining intensities were significantly higher in group B than in A (p < 0.001 and p < 0.05, respectively). The difference in ß-2 staining intensity between groups A and B was not statistically significant. CONCLUSIONS: α-1D adrenoceptor was predominant in patients showing a positive response to topical 0.5% apraclonidine. Because apraclonidine has an α-1 agonistic effect, α-1D adrenoceptor may contribute to apraclonidine's elevating effect in patients with blepharoptosis.


Asunto(s)
Agonistas alfa-Adrenérgicos/administración & dosificación , Blefaroptosis/tratamiento farmacológico , Clonidina/análogos & derivados , Párpados/metabolismo , Receptores Adrenérgicos/metabolismo , Adolescente , Agonistas alfa-Adrenérgicos/efectos adversos , Adulto , Anciano , Niño , Clonidina/administración & dosificación , Clonidina/efectos adversos , Párpados/efectos de los fármacos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
20.
Beilstein J Org Chem ; 14: 243-252, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29441144

RESUMEN

Herein, we describe a novel approach for the practical synthesis of tetrasubstituted thiophenes 8. The developed method was particularly used for the facile preparation of thienyl heterocycles 8. The mechanism for this reaction is based on the formation of a sulfur ylide-like intermediate. It was clearly suggested by (i) the intramolecular cyclization of ketene N,S-acetals 7 to the corresponding thiophenes 8, (ii) 1H NMR studies of Meldrum's acid-substituted aminothioacetals 9, and (iii) substitution studies of the methoxy group on Meldrum's acid containing N,S-acetals 9b. Notably, in terms of structural effects on the reactivity and stability of sulfur ylide-like intermediates, 2-pyridyl substituted compound 7a exhibited superior properties over those of others.

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