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1.
Angew Chem Int Ed Engl ; 60(25): 13835-13839, 2021 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-33826220

RESUMEN

Multiply bonded lanthanide oxo groups are rare in coordination compounds and have not previously been reported for a surface termination of a lanthanide oxide. Here we report the observation of a Ce=O terminated ceria surface in a CeO2 (111)-( 3 × 3 )R30° reconstruction of ≈3 nm thick ceria islands prepared on Pt(111). This is evidenced by scanning tunnelling microscopy (STM), low energy electron diffraction (LEED) and high-resolution electron energy loss spectroscopy (HREELS) measurements in conjunction with density functional theory (DFT) calculations. A Ce=O stretching frequency of 775 cm-1 is observed in HREELS, compared with 766 cm-1 calculated by DFT. The calculations also predict that the Ce=O bond is weak, with an oxygen vacancy formation energy of 0.85 eV. This could play an important role in the facile removal of lattice oxygen from CeO2 , accompanied by the reduction of CeIV to CeIII , which is a key attribute of ceria-based systems in connection with their unique catalytic properties.

2.
Opt Express ; 27(21): 31023-31041, 2019 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-31684343

RESUMEN

Quantum phase estimation (QPE) is the key procedure in various quantum algorithms. The main aim of the QPE scheme is to estimate the phase of an unknown eigenvalue, corresponding to an eigenstate of an arbitrary unitary operation. The QPE scheme can be applied as a subroutine to design many quantum algorithms. In this paper, we propose the basic structure of a QPE scheme that could be applied in quantum algorithms, with feasibility by utilizing cross-Kerr nonlinearities (controlled-unitary gates) and linearly optical devices. Subsequently, we analyze the efficiency and the performance of the controlled-unitary gate. This gate consists of a controlled-path gate and a merging-path gate via cross-Kerr nonlinearities under the decoherence effect. Also shown in this paper is a method by which to enhance robustness against the decoherence effect to provide a reliable QPE scheme based on controlled-unitary gates.

3.
Phys Chem Chem Phys ; 21(20): 10540-10551, 2019 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-31073566

RESUMEN

In this paper, we report that S atoms on Ag(100) and Ag(110) exhibit a distinctive range of appearances in scanning tunneling microscopy (STM) images, depending on the sample bias voltage, VS. Progressing from negative to positive VS, the atomic shape can be described as a round protrusion surrounded by a dark halo (sombrero) in which the central protrusion shrinks, leaving only a round depression. This progression resembles that reported previously for S atoms on Cu(100). We test whether DFT can reproduce these shapes and the transition between them, using a modified version of the Lang-Tersoff-Hamann method to simulate STM images. The sombrero shape is easily reproduced, but the sombrero-depression transition appears only for relatively low tunneling current and correspondingly realistic tip-sample separation, dT, of 0.5-0.8 nm. Achieving these conditions in the calculations requires sufficiently large separation (vacuum) between slabs, together with high energy cutoff, to ensure appropriate exponential decay of electron density into vacuum. From DFT, we also predict that an analogous transition is not expected for S atoms on Ag(111) surfaces. The results are explained in terms of the through-surface conductance, which defines the background level in STM, and through-adsorbate conductance, which defines the apparent height at the point directly above the adsorbate. With increasing VS, for Ag(100) and Ag(110), we show that through-surface conductance increases much more rapidly than through-adsorbate conductance, so the apparent adsorbate height drops below background. In contrast, for Ag(111) the two contributions increase at more comparable rates, so the adsorbate level always remains above background and no transition is seen.

4.
J Am Chem Soc ; 140(19): 6164-6168, 2018 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-29688718

RESUMEN

We present a new polymorph of the two-dimensional (2D) silica film with a characteristic 'zigzag' line structure and a rectangular unit cell which forms on a Ru(0001) metal substrate. This new silica polymorph may allow for important insights into growth modes and transformations of 2D silica films as a model system for the study of glass transitions. Based on scanning tunneling microscopy, low energy electron diffraction, infrared reflection absorption spectroscopy, and X-ray photoelectron spectroscopy measurements on the one hand, and density functional theory calculations on the other, a structural model for the 'zigzag' polymorph is proposed. In comparison to established monolayer and bilayer silica, this 'zigzag' structure system has intermediate characteristics in terms of coupling to the substrate and stoichiometry. The silica 'zigzag' phase is transformed upon reoxidation at higher annealing temperature into a SiO2 silica bilayer film which is chemically decoupled from the substrate.

5.
Hum Mol Genet ; 23(8): 2132-44, 2014 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-24301678

RESUMEN

Phototransduction machinery in vertebrate photoreceptors is contained within the membrane discs of outer segments. Daily renewal of 10% of photoreceptor outer segments requires stringent control of gene expression. Rhodopsin constitutes over 90% of the protein in rod discs, and its altered expression or transport is associated with photoreceptor dysfunction and/or death. Two cis-regulatory sequences have been identified upstream of the rhodopsin transcription start site. While the proximal promoter binds to specific transcription factors, including NRL and CRX, the rhodopsin enhancer region (RER) reportedly contributes to precise and high-level expression of rhodopsin in vivo. Here, we report the identification of RER-bound proteins by mass spectrometry. We validate the binding of NonO (p54(nrb)), a protein implicated in coupling transcription to splicing, and three NonO-interacting proteins-hnRNP M, Ywhaz and Ppp1ca. NonO and its interactors can activate rhodopsin promoter in HEK293 cells and function synergistically with NRL and CRX. DNA-binding domain of NonO is critical for rhodopsin promoter activation. Chromatin immunoprecipitation followed by deep sequencing (ChIP-seq) analysis demonstrates high occupancy of NonO at rhodopsin and a subset of phototransduction genes. Furthermore, shRNA knockdown of NonO in mouse retina leads to loss of rhodopsin expression and rod cell death, which can be partially rescued by a C-terminal NonO construct. RNA-seq analysis of the NonO shRNA-treated retina revealed splicing defects and altered expression of genes, specifically those associated with phototransduction. Our studies identify an important contribution of NonO and its interacting modulator proteins in enhancing rod-specific gene expression and controlling rod homeostasis.


Asunto(s)
Proteínas 14-3-3/metabolismo , Proteínas de Unión al ADN/metabolismo , Elementos de Facilitación Genéticos/genética , Ribonucleoproteína Heterogénea-Nuclear Grupo M/metabolismo , Proteínas Asociadas a Matriz Nuclear/metabolismo , Proteína Fosfatasa 1/metabolismo , Proteínas de Unión al ARN/metabolismo , Rodopsina/metabolismo , Proteínas 14-3-3/genética , Animales , Biomarcadores/metabolismo , Western Blotting , Bovinos , Células Cultivadas , Inmunoprecipitación de Cromatina , Proteínas de Unión al ADN/genética , Perfilación de la Expresión Génica , Células HEK293 , Ribonucleoproteína Heterogénea-Nuclear Grupo M/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Técnicas para Inmunoenzimas , Inmunoprecipitación , Ratones , Ratones Endogámicos C57BL , Proteínas Asociadas a Matriz Nuclear/genética , Regiones Promotoras Genéticas/genética , Proteína Fosfatasa 1/genética , Empalme del ARN/genética , ARN Mensajero/genética , Proteínas de Unión al ARN/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Retina/citología , Retina/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transcripción Genética/genética
6.
Hum Mol Genet ; 23(16): 4260-71, 2014 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-24691551

RESUMEN

The Maf-family leucine zipper transcription factor NRL is essential for rod photoreceptor development and functional maintenance in the mammalian retina. Mutations in NRL are associated with human retinopathies, and loss of Nrl in mice leads to a cone-only retina with the complete absence of rods. Among the highly down-regulated genes in the Nrl(-/-) retina, we identified receptor expression enhancing protein 6 (Reep6), which encodes a member of a family of proteins involved in shaping of membrane tubules and transport of G-protein coupled receptors. Here, we demonstrate the expression of a novel Reep6 isoform (termed Reep6.1) in the retina by exon-specific Taqman assay and rapid analysis of complementary deoxyribonucleic acid (cDNA) ends (5'-RACE). The REEP6.1 protein includes 27 additional amino acids encoded by exon 5 and is specifically expressed in rod photoreceptors of developing and mature retina. Chromatin immunoprecipitation assay identified NRL binding within the Reep6 intron 1. Reporter assays in cultured cells and transfections in retinal explants mapped an intronic enhancer sequence that mediated NRL-directed Reep6.1 expression. We also demonstrate that knockdown of Reep6 in mouse and zebrafish resulted in death of retinal cells. Our studies implicate REEP6.1 as a key functional target of NRL-centered transcriptional regulatory network in rod photoreceptors.


Asunto(s)
Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Proteínas del Ojo/genética , Proteínas de Transporte de Membrana/química , Isoformas de Proteínas/genética , Células Fotorreceptoras Retinianas Bastones/metabolismo , Activación Transcripcional , Animales , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Elementos de Facilitación Genéticos , Proteínas del Ojo/metabolismo , Redes Reguladoras de Genes , Células HEK293 , Humanos , Intrones , Proteínas de la Membrana , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Ratones Endogámicos C57BL , Especificidad de Órganos , Isoformas de Proteínas/metabolismo , Pez Cebra
7.
Chemphyschem ; 17(14): 2137-45, 2016 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-27124261

RESUMEN

Using scanning tunneling microscopy (STM), we observed that adsorption of Se on Cu(111) produced islands with a (√3×√3)R30° structure at Se coverages far below the structure's ideal coverage of 1/3 monolayer. On the basis of density functional theory (DFT), these islands cannot form due to attractive interactions between chemisorbed Se atoms. DFT showed that incorporating Cu atoms into the √3-Se lattice stabilizes the structure, which provided a plausible explanation for the experimental observations. STM revealed three types of √3 textures. We assigned two of these as two-dimensional layers of strained CuSe, analogous to dense planes of bulk klockmannite (CuSe). Klockmannite has a bulk lattice constant that is 11 % shorter than √3 times the surface lattice constant of Cu(111). This offers a rationale for the differences observed between these textures, for which strain limits the island size or distorts the √3 lattice. STM showed that existing step edges adsorb Se and facet toward ⟨12‾ 1⟩, which is consistent with DFT.

8.
Phys Chem Chem Phys ; 18(6): 4891-901, 2016 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-26806090

RESUMEN

Using a combination of scanning tunneling microscopy and density functional theory (DFT) calculations, we have identified a set of related Au-S complexes that form on Au(100), when sulfur adsorbs and lifts the hexagonal surface reconstruction. The predominant complex is diamond-shaped with stoichiometry Au4S5. All of the complexes can be regarded as combinations of S-Au-S subunits. The complexes exist within, or at the edges of, p(2 × 2) sulfur islands that cover the unreconstructed Au regions, and are observed throughout the range of S coverage examined in this study, 0.009 to 0.12 monolayers. A qualitative model is developed which incorporates competitive formation of complexes, Au rafts, and p(2 × 2) sulfur islands, as Au atoms are released by the surface structure transformation.

9.
Aesthetic Plast Surg ; 40(3): 428-34, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27102776

RESUMEN

BACKGROUND: A rise in cosmetic procedures has seen the use of fillers become more prevalent. Complications resulting from use of fillers have prompted introduction of various medical and surgical interventions. Recently, stem cell therapies have become more widely used as a new treatment option for tissue repair and regeneration. METHODS: We utilized adipose-derived stem cells (ASCs) for tissue regeneration in patients with filler-related complications such as necrosis. All 12 patients were treated with ASCs and some patients had additional treatment. After relief of symptoms, wound surface area was compared in terms of pixel numbers and scar condition was evaluated using the Vancouver Scar Scale (VSS). RESULTS: In general, we achieved satisfactory resolution of filler-related complications in a short period of time without serious side effects. The average number of days from stem cell treatment to symptom relief was 7.3 days. The proportion of wound surface area from photographic record was 4.39 % before treatment, decreasing considerably to 1.01 % following treatment. Last, the VSS showed almost all patients scored below 3, with two patients receiving scores of 7 and 8; the average score was 2.78 (range from 0 to 8). CONCLUSIONS: ASCs are a new treatment option for post-filler injection wounds such as necrosis. Using stem cells, we were able to obtain satisfactory results in a short period of time without complications requiring surgical procedures. We suggest stem cell injections could be used as the first option for treatment of complications from filler injections. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Asunto(s)
Adipocitos/trasplante , Técnicas Cosméticas/efectos adversos , Rellenos Dérmicos/efectos adversos , Piel/patología , Trasplante de Células Madre/métodos , Adulto , Estudios de Cohortes , Estética , Femenino , Humanos , Persona de Mediana Edad , Necrosis/patología , Necrosis/terapia , Estudios Retrospectivos , Medición de Riesgo , Resultado del Tratamiento , Cicatrización de Heridas/fisiología , Adulto Joven
10.
Cells Tissues Organs ; 199(5-6): 373-83, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25823468

RESUMEN

Human adipose tissue-derived mesenchymal stem cells (AT-MSCs) from various sites are applied in tissue engineering and cell therapy. The condition of AT-MSCs depends on the donor's age, body mass index (BMI), and gender. AT-MSCs from 66 human donors were analyzed, and the cells were sorted according to donor age (10-19 years: n = 1; 20-29 years: n = 5; 30-39 years: n = 12; 40-49 years: n = 22; 50-59 years: n = 12; 60-69 years: n = 9, and 70 years or older: n = 5), BMI (under 25, 25-30, and over 30), and gender (19 males and 48 females). Additionally, AT-MSCs were compared to bone marrow MSCs and chorionic tissue-derived MSCs. We measured the MSC yield, growth rate, colony-forming units, multipotency, and surface antigens. AT-MSC proliferation was greater in cells isolated from individuals aged less than 30 years compared to the proliferation of AT-MSCs from those over 50 years old. BMI was correlated with osteogenic differentiation potency; increased BMI enhanced osteogenesis. Adipogenic differentiation was more strongly induced in cells isolated from donors aged less than 30 years compared to those isolated from other age groups. Also, a BMI above 30 was associated with enhanced adipogenic differentiation compared to cells isolated from individuals with a BMI below 25. Bone marrow MSCs were strongly induced to differentiate along both osteogenic and adipogenic lineages, whereas AT-MSCs predominantly differentiated into the chondrogenic lineage. Therefore, the type of regeneration required and variations among potential donors must be carefully considered when selecting MSCs for use in applied tissue engineering or cell therapy.


Asunto(s)
Tejido Adiposo/metabolismo , Células Madre Mesenquimatosas/metabolismo , Tejido Adiposo/citología , Adolescente , Adulto , Anciano , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Donantes de Tejidos , Adulto Joven
11.
J Chem Phys ; 140(11): 114707, 2014 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-24655198

RESUMEN

The surface morphology of chemisorbed N on the Pt(111) surface has been studied at the atomic level with low temperature scanning tunneling microscopy (STM). When N is coadsorbed with O on the surface, they form a mixed (2 × 2)-N+O structure. When the surface is covered with N atoms only, isolated atoms and incomplete (2 × 2) patches are observed at low coverages. In a dense N layer, two phases, (√3 × âˆš3)R30°-N and p(2 × 2)-N, are found to coexist at temperatures between 360 and 400 K. The (√3 × âˆš3)R30° phase converts to the (2 × 2) phase as temperature increases. For both phases, nitrogen occupies fcc-hollow sites. At temperatures above 420 K, nitrogen starts to desorb. The p(2 × 2)-N phase shows a honeycomb structure in STM images with three nitrogen and three platinum atoms forming a six-membered ring, which can be attributed to the strong nitrogen binding to the underlying Pt surface.

12.
Aesthetic Plast Surg ; 38(5): 1001-10, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25099494

RESUMEN

Over the past few years, the clinical use of injectable artificial materials in plastic surgery has increased. In addition, autologous lipoimplantation is being performed for volume replacement of soft tissue for aesthetic purposes. In this study, acellular allogenic dermis was utilized as a scaffold for the culturing of preadipocytes, confirming the possibility of three-dimensional proliferation of progenitor cells, the eventual differentiation of stromal cells in adipose tissue into the adipocytes, and the in vivo implantation of such adipocytes to form fat tissue. Preadipocytes, recently called ASCs (adipose tissue-derived stromal/stem cells), were cultured in acellular allogenic dermis, successfully attached to the dermal particles in a three-dimensional structure, and proliferated, differentiated, and eventually formed a cluster. For the in vivo implantation, four groups were formed: the first group was cultured within the dermal scaffold for 24 h before implantation (24-h preconditioned group), the second group was induced for differentiation for 10 days before implantation (10-day preconditioned group), the third group was implanted immediately after cell propagation (nonpreconditioned group), and the control group was implanted with only dermal scaffold. In vivo implanted preadipocytes showed great differentiation into adipocytes within the dermal scaffolds. Also, the 10-day preconditioned group showed a greater volume of fat tissue compared to the 24-h preconditioned group. From these results, we confirmed that after a three-dimensional culture in acellular allogenic dermis, implanted preadipocytes formed a greater amount of fat tissue and that this could be a possible effective method for future soft tissue restoration.


Asunto(s)
Dermis Acelular , Adipocitos/citología , Trasplante de Células Madre/métodos , Andamios del Tejido , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Humanos , Microscopía Confocal , Células Madre/citología , Ingeniería de Tejidos/métodos
13.
Aesthetic Plast Surg ; 37(5): 1041-51, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23877753

RESUMEN

A satisfying result is difficult to achieve in the repair of a full-thickness skin defect in the facial area, including the subunits of the nose. A full-thickness skin graft, nasolabial flap, or forehead flap as a major treatment still is used despite its relative potential for secondary contracture, unmatched skin color, hypertrophic scars, and donor-site morbidity. Another option, with good wound-healing power and soft tissue regeneration without skin grafts would be helpful for initiating treatment. Adult stem cells are a useful material in tissue engineering. Adipose-derived stem cells (ADSCs), an abundant population of pluripotent cells found in the stroma of adipose tissues, have been shown to differentiate in vitro into various cell lineages. As a robust source of bioactive growth factors, ADSCs contribute to recovery from ischemic damage, and they can promote the wound-healing process as well as soft tissue regeneration. The authors have experienced several cases of facial skin defect repair using ADSCs without skin grafts. In these cases, they observed rapid coverage of the wound with the patient's own regenerated tissue. During the treatment period, ADSC treatment showed an excellent wound-healing process in terms of quantity and quality.


Asunto(s)
Células Madre Pluripotentes/trasplante , Rinoplastia , Trasplante de Células Madre , Ingeniería de Tejidos/métodos , Cicatrización de Heridas/fisiología , Tejido Adiposo/citología , Tejido Adiposo/trasplante , Adulto , Humanos , Masculino , Regeneración/fisiología , Rinoplastia/efectos adversos , Células Madre/fisiología , Andamios del Tejido , Adulto Joven
14.
J Phys Chem C Nanomater Interfaces ; 126(7): 3736-3742, 2022 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-35242273

RESUMEN

Silica films represent a unique two-dimensional film system, exhibiting both crystalline and vitreous forms. While much scientific work has focused on the atomic-scale features of this film system, mesoscale structures can play an important role for understanding confined space reactions and other applications of silica films. Here, we report on mesoscale structures in silica films grown under ultrahigh vacuum and examined with scanning tunneling microscopy (STM). Silica films can exhibit coexisting phases of monolayer, zigzag, and bilayer structures. Both holes in the film structure and atomic-scale substrate steps are observed to influence these coexisting phases. In particular, film regions bordering holes in silica bilayer films exhibit vitreous character, even in regions where the majority film structure is crystalline. At high coverages mixed zigzag and bilayer phases are observed at step edges, while at lower coverages silica phases with lower silicon densities are observed more prevalently near step edges. The STM images reveal that silica films exhibit rich structural diversity at the mesoscale.

15.
Pediatr Rheumatol Online J ; 19(1): 76, 2021 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-34059085

RESUMEN

BACKGROUND: Kawasaki disease (KD) is an acute, self-limited febrile illness of unknown cause. Intravenous immunoglobulin (IVIG)-resistance are related to greater risk for permanent cardiac complications. We aimed to determine the correlation between monocytes and the phenotype of KD in relation to IVIG responsiveness in children. MATERIALS AND METHODS: The study cohort included 62 patients who were diagnosed with KD, 20 non febrile healthy controls (NFC), and 15 other febrile controls (OFC). In all enrolled patients, blood was taken at least 4 times and laboratory tests were performed. In addition, subtypes of monocytes were characterized via flow cytometry. RESULTS: The numbers of intermediate monocytes were significantly lower in IVIG-resistant group compared to IVIG-responsive group before IVIG infusion (p < 0.0001). After infusion, intermediate monocytes decreased in the responsive group, while a trend of increase was observed in the resistant group. Only intermediate monocytes were significant in logistic regression with adjusted OR of 0.001 and p value of 0.03. CONCLUSIONS: CD14 + CD16 + intermediate monocyte may play an important role in IVIG responsiveness among KD children. Low starting levels of intermediate monocytes, followed by a dramatic increase post-IVIG infusion during acute phase of KD are associated with IVIG-resistance. Functional studies on intermediate monocyte may help to reveal the pathophysiology.


Asunto(s)
Inmunoglobulinas Intravenosas , Receptores de Lipopolisacáridos/inmunología , Monocitos , Síndrome Mucocutáneo Linfonodular , Receptores de IgG/inmunología , Biomarcadores Farmacológicos/análisis , Preescolar , Femenino , Fiebre/sangre , Fiebre/inmunología , Citometría de Flujo/métodos , Proteínas Ligadas a GPI/inmunología , Humanos , Inmunoglobulinas Intravenosas/administración & dosificación , Inmunoglobulinas Intravenosas/inmunología , Factores Inmunológicos/administración & dosificación , Factores Inmunológicos/inmunología , Inmunofenotipificación/métodos , Masculino , Monocitos/inmunología , Monocitos/patología , Síndrome Mucocutáneo Linfonodular/sangre , Síndrome Mucocutáneo Linfonodular/diagnóstico , Síndrome Mucocutáneo Linfonodular/inmunología , Síndrome Mucocutáneo Linfonodular/terapia , Gravedad del Paciente , Resultado del Tratamiento
16.
Oncoimmunology ; 10(1): 2005280, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34858729

RESUMEN

Kynurenine (Kyn) is a key inducer of an immunosuppressive tumor microenvironment (TME). Although indoleamine 2,3-dioxygenase (IDO)-selective inhibitors have been developed to suppress the Kyn pathway, the results were not satisfactory due to the presence of various opposing mechanisms. Here, we employed an orally administered novel Kyn pathway regulator to overcome the limitation of anti-tumor immune response. We identified a novel core structure that inhibited both IDO and TDO. An orally available lead compound, STB-C017 (designated hereafter as STB), effectively inhibited the enzymatic and cellular activity of IDO and TDO in vitro. Moreover, it potently suppressed Kyn levels in both the plasma and tumor in vivo. STB monotherapy increased the infiltration of CD8+ T cells into TME. In addition, STB reprogrammed the TME with widespread changes in immune-mediated gene signatures. Notably, STB-based combination immunotherapy elicited the most potent anti-tumor efficacy through concurrent treatment with immune checkpoint inhibitors, leading to complete tumor regression and long-term overall survival. Our study demonstrated that a novel Kyn pathway regulator derived using deep learning technology can activate T cell immunity and potentiate immune checkpoint blockade by overcoming an immunosuppressive TME.


Asunto(s)
Aprendizaje Profundo , Quinurenina , Linfocitos T CD8-positivos , Inmunoterapia , Indolamina-Pirrol 2,3,-Dioxigenasa/genética
17.
Mol Cell Neurosci ; 42(4): 267-77, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19646530

RESUMEN

The sequential steps of neurogenesis are characterized by highly choreographed changes in transcription factor activity. In contrast to the well-studied mechanisms of transcription factor activation during neurogenesis, much less is understood regarding how such activity is terminated. We previously showed that MTGR1, a member of the MTG family of transcriptional repressors, is strongly induced by a proneural basic helix-loop-helix transcription factor, NEUROG2 in developing nervous system. In this study, we describe a novel feedback regulation of NEUROG2 activity by MTGR1. We show that MTGR1 physically interacts with NEUROG2 and represses transcriptional activity of NEUROG2. MTGR1 also prevents DNA binding of the NEUROG2/E47 complex. In addition, we provide evidence that proper termination of NEUROG2 activity by MTGR1 is necessary for normal progression of neurogenesis in the developing spinal cord. These results highlight the importance of feedback regulation of proneural gene activity in neurodevelopment.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Retroalimentación , Regulación del Desarrollo de la Expresión Génica , Proteínas del Tejido Nervioso/metabolismo , Neurogénesis/fisiología , Proteínas Represoras/metabolismo , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Diferenciación Celular/fisiología , Embrión de Pollo , ADN/metabolismo , Proteínas del Tejido Nervioso/genética , Neuronas/citología , Neuronas/fisiología , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Proteínas Represoras/genética , Médula Espinal/citología , Médula Espinal/embriología , Médula Espinal/metabolismo , Factores de Transcripción TCF/genética , Factores de Transcripción TCF/metabolismo , Proteína 1 Similar al Factor de Transcripción 7 , Transcripción Genética
18.
Dev Dyn ; 238(11): 2823-36, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19842182

RESUMEN

Progenitor cells in the developing retina initially divide so that each division produces two cells that divide again. Subsequently, progenitor cells change their mode of division so that one or both cells produced by a division can withdraw from the mitotic cycle and differentiate. We asked how these two progenitor cell stages differ molecularly and what controls the switch in the mode of division. We show that early preneurogenic progenitor cells express the transcription factor, Sox2, and the Notch ligand, Delta1. More mature neurogenic progenitor cells express Sox2 and the bHLH transcription factor, E2A, and not Delta1. Notch signaling maintains progenitor cells in the preneurogenic state. Sonic hedgehog expressed by newly differentiating cells initiates maturation of progenitor cells from preneurogenic to neurogenic at the neurogenic front, possibly by down-regulating Delta1 expression. Our results show that the preneurogenic-to-neurogenic transition is a highly organized unidirectional step made in unison by neighboring cells.


Asunto(s)
Neurogénesis , Retina/embriología , Células Madre/metabolismo , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Diferenciación Celular/fisiología , Embrión de Pollo , Proteínas Hedgehog/metabolismo , Péptidos y Proteínas de Señalización Intracelular , Proteínas de la Membrana/metabolismo , Retina/citología , Retina/metabolismo , Factores de Transcripción SOXB1/metabolismo , Transducción de Señal/fisiología , Células Madre/citología
19.
Plast Reconstr Surg Glob Open ; 6(11): e1967, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30881784

RESUMEN

BACKGROUND: Strong strut structures are necessary for nasal tip projection in Asian rhinoplasty. Traditionally, strut structures have been constructed by open skin incisions. METHODS: Barbed threads were implanted for rhinoplasties. The threads have multiple sharp barbs and umbrella-like longitudinal splits at both ends. Autologous micronized fat tissue graft was also simultaneously used when volume replacement was necessary. RESULTS: Since 2003, barbed threads have been used in approximately 1,200 rhinoplasties for nasal tip projection, dorsal length elongation, and nostril correction. The results of relative length ratios comparing true lateral photographs showed significant increase in tip projection. CONCLUSION: The results of long-term observation (> 6 months) indicate that the surgical procedure of lifting the nasal tips with barbed threads is significantly effective for the anterior projection of nasal tip in Asians.

20.
J Phys Chem B ; 122(2): 963-971, 2018 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-28829614

RESUMEN

Using scanning tunneling microscopy, we characterize the size and bias-dependent shape of sulfur atoms on Cu(100) at low coverage (below 0.1 monolayers) and low temperature (quenched from 300 to 5 K). Sulfur atoms populate the Cu(100) terraces more heavily than steps at low coverage, but as coverage approaches 0.1 monolayers, close-packed step edges become fully populated, with sulfur atoms occupying sites on top of the step. Density functional theory (DFT) corroborates the preferential population of terraces at low coverage as well as the step adsorption site. In experiment, small regions with p(2 × 2)-like atomic arrangements emerge on the terraces as sulfur coverage approaches 0.1 monolayer. Using DFT, a lattice gas model has been developed, and Monte Carlo simulations based on this model have been compared with the observed terrace configurations. A model containing eight pairwise interaction energies, all repulsive, gives qualitative agreement. Experiment shows that atomic adsorbed sulfur is the only species on Cu(100) up to a coverage of 0.09 monolayers. There are no Cu-S complexes. In contrast, prior work has shown that a Cu2S3 complex forms on Cu(111) under comparable conditions. On the basis of DFT, this difference can be attributed mainly to stronger adsorption of sulfur on Cu(100) as compared with Cu(111).

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