Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
J Autoimmun ; 148: 103293, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39096717

RESUMEN

Psoriasis is a chronic, proliferative, and inflammatory skin disease closely associated with inflammatory cytokine production. Cyclophilin A (CypA) is an important proinflammatory factor; however, its role in psoriasis remains unclear. The present data indicate that CypA levels are increased in the lesion skin and serum of patients with psoriasis, which is positively correlated with the psoriasis area severity index. Furthermore, extracellular CypA (eCypA) triggered psoriasis-like inflammatory responses in keratinocytes. Moreover, anti-CypA mAb significantly reduced pathological injury, keratinocyte proliferation, cytokine expression in imiquimod-induced mice. Notably, the therapeutic effect of anti-CypA mAb was better than that of the clinically used anti-IL-17A mAb and methotrexate. Mechanistically, eCypA binds to ACE2 and CD147 and is blocked by anti-CypA mAb. eCypA not only induces the dimerization and phosphorylation of ACE2 to trigger the JAK1/STAT3 signaling pathway for cytokine expression but also interacts with CD147 to promote PI3K/AKT/mTOR signaling-mediated keratinocyte proliferation. These findings demonstrate that the binding of eCypA to ACE2 and CD147 cooperatively triggers psoriasis-like inflammation and anti-CypA mAb is a promising candidate for the treatment of psoriasis.


Asunto(s)
Enzima Convertidora de Angiotensina 2 , Basigina , Ciclofilina A , Queratinocitos , Unión Proteica , Psoriasis , Transducción de Señal , Basigina/metabolismo , Basigina/inmunología , Ciclofilina A/metabolismo , Humanos , Animales , Psoriasis/metabolismo , Psoriasis/inmunología , Ratones , Queratinocitos/metabolismo , Queratinocitos/inmunología , Enzima Convertidora de Angiotensina 2/metabolismo , Inflamación/metabolismo , Inflamación/inmunología , Modelos Animales de Enfermedad , Masculino , Femenino , Proliferación Celular , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/uso terapéutico , Citocinas/metabolismo
2.
Emerg Microbes Infect ; 13(1): 2372344, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38916407

RESUMEN

The Orthopoxvirus (OPXV) genus of the Poxviridae includes human pathogens variola virus (VARV), monkeypox virus (MPXV), vaccinia virus (VACV), and a number of zoonotic viruses. A number of Bcl-2-like proteins of VACV are involved in escaping the host innate immunity. However, little work has been devoted to the evolution and function of their orthologues in other OPXVs. Here, we found that MPXV protein P2, encoded by the P2L gene, and P2 orthologues from other OPXVs, such as VACV protein N2, localize to the nucleus and antagonize interferon (IFN) production. Exceptions to this were the truncated P2 orthologues in camelpox virus (CMLV) and taterapox virus (TATV) that lacked the nuclear localization signal (NLS). Mechanistically, the NLS of MPXV P2 interacted with karyopherin α-2 (KPNA2) to facilitate P2 nuclear translocation, and competitively inhibited KPNA2-mediated IRF3 nuclear translocation and downstream IFN production. Deletion of the NLS in P2 or orthologues significantly enhanced IRF3 nuclear translocation and innate immune responses, thereby reducing viral replication. Moreover, deletion of NLS from N2 in VACV attenuated viral replication and virulence in mice. These data demonstrate that the NLS-mediated translocation of P2 is critical for P2-induced inhibition of innate immunity. Our findings contribute to an in-depth understanding of the mechanisms of OPXV P2 orthologue in innate immune evasion.


Asunto(s)
Inmunidad Innata , Factor 3 Regulador del Interferón , Monkeypox virus , Señales de Localización Nuclear , Proteínas Virales , Animales , Factor 3 Regulador del Interferón/metabolismo , Factor 3 Regulador del Interferón/genética , Ratones , Humanos , Proteínas Virales/genética , Proteínas Virales/metabolismo , Proteínas Virales/inmunología , Señales de Localización Nuclear/genética , Monkeypox virus/genética , Monkeypox virus/inmunología , Células HEK293 , alfa Carioferinas/genética , alfa Carioferinas/metabolismo , Evasión Inmune , Núcleo Celular/metabolismo , Interferones/genética , Interferones/inmunología , Interferones/metabolismo , Infecciones por Poxviridae/inmunología , Infecciones por Poxviridae/virología , Infecciones por Poxviridae/veterinaria , Ratones Endogámicos C57BL
3.
Mol Ther ; 32(5): 1510-1525, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38454605

RESUMEN

The acute respiratory virus infection can induce uncontrolled inflammatory responses, such as cytokine storm and viral pneumonia, which are the major causes of death in clinical cases. Cyclophilin A (CypA) is mainly distributed in the cytoplasm of resting cells and released into the extracellular space in response to inflammatory stimuli. Extracellular CypA (eCypA) is upregulated and promotes inflammatory response in severe COVID-19 patients. However, how eCypA promotes virus-induced inflammatory response remains elusive. Here, we observe that eCypA is induced by influenza A and B viruses and SARS-CoV-2 in cells, mice, or patients. Anti-CypA mAb reduces pro-inflammatory cytokines production, leukocytes infiltration, and lung injury in virus-infected mice. Mechanistically, eCypA binding to integrin ß2 triggers integrin activation, thereby facilitating leukocyte trafficking and cytokines production via the focal adhesion kinase (FAK)/GTPase and FAK/ERK/P65 pathways, respectively. These functions are suppressed by the anti-CypA mAb that specifically blocks eCypA-integrin ß2 interaction. Overall, our findings reveal that eCypA-integrin ß2 signaling mediates virus-induced inflammatory response, indicating that eCypA is a potential target for antibody therapy against viral pneumonia.


Asunto(s)
COVID-19 , Ciclofilina A , Ciclofilina A/metabolismo , Animales , Humanos , Ratones , COVID-19/metabolismo , COVID-19/virología , COVID-19/inmunología , Antígenos CD18/metabolismo , SARS-CoV-2 , Neumonía Viral/tratamiento farmacológico , Neumonía Viral/virología , Neumonía Viral/metabolismo , Neumonía Viral/inmunología , Citocinas/metabolismo , Anticuerpos Monoclonales/farmacología , Transducción de Señal , Virus de la Influenza A , Modelos Animales de Enfermedad
4.
iScience ; 26(12): 108515, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38089580

RESUMEN

Influenza B circulates annually and causes substantial disease burden in humans. However, little is known about the infection mechanisms of influenza B virus (IBV). Here, we find that the host factor cyclophilin A (CypA) facilitates IBV replication by targeting IBV non-structural protein 1 (BNS1) and nucleoprotein (BNP). CypA promotes OTUD4-mediated K48-linked BNS1 deubiquitination to stabilize BNS1 by upregulating OTUD4 expression. Meanwhile, CypA and the E3 ligase MIB1 competitively interact with BNP to inhibit its proteasomal degradation. Moreover, cyclosporine A treatment or CypA R55A mutation results in an impaired function of CypA in IBV replication. Notably, BNP hijacks CypA into the nucleus to enhance the activity of viral ribonucleoprotein complexes by enhancing the interaction between BNP and IBV polymerase basic protein 1. Taken together, this study unveils the critical role of CypA in facilitating IBV replication, suggesting that CypA is a promising target for anti-IBV drug.

5.
Sheng Wu Gong Cheng Xue Bao ; 39(12): 4796-4808, 2023 Dec 25.
Artículo en Chino | MEDLINE | ID: mdl-38147982

RESUMEN

This study aimed to explore the mechanism of how African swine fever virus (ASFV) I226R protein inhibits the cGAS-STING signaling pathway. We observed that I226R protein (pI226R) significantly inhibited the cGAS-STING-mediated type Ⅰ interferons and the interferon-stimulated genes production by dual-luciferase reporter assay system and real-time quantitative PCR. The results of co-immunoprecipitation assay and confocal microscopy showed that pI226R interacted with cGAS. Furthermore, pI226R promoted cGAS degradation through autophagy-lysosome pathway. Moreover, we found that pI226R decreased the binding of cGAS to E3 ligase tripartite motif protein 56 (TRIM56), resulting in the weakened monoubiquitination of cGAS, thus inhibiting the activation of cGAS and cGAS-STING signaling. In conclusion, ASFV pI226R suppresses the antiviral innate immune response by antagonizing cGAS, which contributes to an in-depth understanding of the immune escape mechanism of ASFV and provides a theoretical basis for the development of vaccines.


Asunto(s)
Virus de la Fiebre Porcina Africana , Animales , Porcinos , Virus de la Fiebre Porcina Africana/genética , Virus de la Fiebre Porcina Africana/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Inmunidad Innata , Nucleotidiltransferasas/genética , Nucleotidiltransferasas/metabolismo , Transducción de Señal/genética
6.
Sheng Wu Gong Cheng Xue Bao ; 39(12): 4809-4823, 2023 Dec 25.
Artículo en Chino | MEDLINE | ID: mdl-38147983

RESUMEN

In order to understand the prevalence and evolution of porcine reproductive and respiratory syndrome virus (PRRSV) in China and to develop subunit vaccine against the epidemic lineage, the genetic evolution analysis of PRRSV strains isolated in China from 2001 to 2021 was performed. The representative strains of the dominant epidemic lineage were selected to optimize the membrane protein GP5 and M nucleotide sequences, which were used, with the interferon and the Fc region of immunoglobulin, to construct the eukaryotic expression plasmids pCDNA3.4-IFNα-GP5-Fc and pCDNA3.4-IFNα-M-Fc. Subsequently, the recombinant proteins IFNα-GP5-Fc and IFNα-M-Fc were expressed by HEK293T eukaryotic expression system. The two recombinant proteins were mixed with ISA206VG adjuvant to immunize weaned piglets. The humoral immunity level was evaluated by ELISA and neutralization test, and the cellular immunity level was detected by ELISPOT test. The results showed that the NADC30-like lineage was the main epidemic lineage in China in recent years, and the combination of IFNα-GP5-Fc and IFNα-M-Fc could induce high levels of antibody and cellular immunity in piglets. This study may facilitate the preparation of a safer and more effective new PRRSV subunit vaccine.


Asunto(s)
Síndrome Respiratorio y de la Reproducción Porcina , Virus del Síndrome Respiratorio y Reproductivo Porcino , Vacunas Virales , Humanos , Animales , Porcinos , Virus del Síndrome Respiratorio y Reproductivo Porcino/genética , Síndrome Respiratorio y de la Reproducción Porcina/prevención & control , Células HEK293 , Proteínas del Envoltorio Viral/genética , Anticuerpos Antivirales , Vacunas Virales/genética , Proteínas Recombinantes , Vacunas de Subunidad
7.
Autophagy ; 19(12): 3113-3131, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37482689

RESUMEN

ABBREVIATIONS: aa: amino acid; ATF6: activating transcription factor 6; ATG5: autophagy related 5; CCPG1: cell cycle progression 1; CFTR: CF transmembrane conductance regulator; cGAMP: cyclic GMP-AMP; CGAS: cyclic GMP-AMP synthase; CHX: cycloheximide; Co-IP: co-immunoprecipitation; CQ: chloroquine; EIF2A/eIF2α: eukaryotic translation initiation factor 2A; EIF2AK3/PERK: eukaryotic translation initiation factor 2 alpha kinase 3; ER: endoplasmic reticulum; ERN1/IRE1: endoplasmic reticulum to nucleus signaling 1; GFP: green fluorescent protein; HSPA5/GRP78: heat shock protein family A (Hsp70) member 5; HSV-1: herpes simplex virus type 1; IFIT1: interferon induced protein with tetratricopeptide repeats 1; IFNB1/IFN-ß: interferon beta 1; IRF3: interferon regulatory factor 3; ISG15: ISG15 ubiquitin like modifier; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MAP3K7/TAK1: mitogen-activated protein kinase kinase kinase 7; MAVS: mitochondrial antiviral signaling protein; MOI: multiplicity of infection; NFKB/NF-κB: nuclear factor kappa B; NSP6: non-structural protein 6; Δ106-108: deletion of amino acids 106-108 in NSP6 of SARS-CoV-2; Δ105-107: deletion of amino acids 105-107 in NSP6 of SARS-CoV-2; RETREG1/FAM134B: reticulophagy regulator 1; RIGI/DDX58: RNA sensor RIG-I; SQSTM1/p62: sequestosome 1; STING1: stimulator of interferon response cGAMP interactor 1; TBK1: TANK binding kinase 1.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Autofagia/fisiología , Estrés del Retículo Endoplásmico/fisiología , Chaperón BiP del Retículo Endoplásmico , Interferones , Aminoácidos
8.
Planta Med ; 89(7): 709-717, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36513369

RESUMEN

Radix arnebiae oil (RAO) is a clinically useful traditional Chinese medical formula with outstanding curative effects on burns. However, the mechanism of the effect of RAO on wound healing remains unclear. The present study investigates the molecular mechanisms of the potential curative effect of RAO on wound healing. The concentrations of the main constituents, shikonin, imperatorin, and ferulic acid in RAO detected by HPLC were 24.57, 3.15, and 0.13 mg/mL, respectively. A rat burn model was established, and macroscopic and histopathological studies were performed. RAO significantly accelerated wound closure and repair scarring, increased superoxide dismutase activities, and reduced malondialdehyde. RAO also downregulated interleukin (IL)-6, IL-1ß and tumor necrosis factor-α in wound tissues and increased secretion of vascular endothelial growth factor, epidermal growth factor, and transforming growth factor (TGF)-ß1. RAO increased the gene expression of TGF-ß1, type I and III collagen, and increased the protein expression of TGF-ß1 and phosphorylation of PI3K and Akt. In conclusion, RAO likely promotes wound healing via antioxidant and anti-inflammatory activities and increases re-epithelization. Activation of the TGF-ß1/PI3K/Akt pathway may play an important role in the healing efficacy of RAO. These findings suggest that RAO could be a promising alternative local treatment for burn wound healing.


Asunto(s)
Quemaduras , Cicatrización de Heridas , Ratas , Animales , Factor de Crecimiento Transformador beta1/metabolismo , Proteínas Proto-Oncogénicas c-akt , Factor A de Crecimiento Endotelial Vascular/farmacología , Fosfatidilinositol 3-Quinasas , Quemaduras/tratamiento farmacológico
9.
Front Immunol ; 13: 861292, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35693825

RESUMEN

Cyclosporine A (CsA) is an immunosuppressive drug that suppresses T cell responses and is broadly used in transplantation. Its immunosuppressive action is closely linked to its binding of cyclophilin A (CypA), which widely distributed in different cell types. CsA also regulates the functions of innate immune cells, but the mechanism remains elusive. Here, we investigate the role of CsA in regulating macrophages polarization in influenza A virus-infected mice and mouse bone marrow-derived macrophages. CsA downregulates pro-inflammatory cytokines expression and upregulates anti-inflammatory cytokines expression. Mechanically, CsA decreases the polarization of macrophages into pro-inflammatory M1 phenotype and increases the polarization of macrophages into anti-inflammatory M2 phenotype. Further studies show that CsA regulates macrophages polarization-associated IFN-γ/STAT1 and IL-4/STAT6 signaling pathways. Meanwhile, all these roles of CsA are eliminated when CypA is absent, suggesting that CsA regulates macrophages polarization and inflammatory responses depend on its binding to CypA. Collectively, these results reveal a crucial mechanism of CsA in attenuating IAV-induced inflammatory responses by a switch in macrophages polarization.


Asunto(s)
Ciclofilina A , Virus de la Influenza A , Animales , Ciclofilina A/metabolismo , Ciclosporina/farmacología , Citocinas , Virus de la Influenza A/fisiología , Macrófagos , Ratones
10.
Microsyst Nanoeng ; 8: 24, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35251689

RESUMEN

Accurate motion feature extraction and recognition provide critical information for many scientific problems. Herein, a new paradigm for a wearable seamless multimode sensor with the ability to decouple pressure and strain stimuli and recognize the different joint motion states is reported. This wearable sensor is integrated into a unique seamless structure consisting of two main parts (a resistive component and a capacitive component) to decouple the different stimuli by an independent resistance-capacitance sensing mechanism. The sensor exhibits both high strain sensitivity (GF = 7.62, 0-140% strain) under the resistance mechanism and high linear pressure sensitivity (S = 3.4 kPa-1, 0-14 kPa) under the capacitive mechanism. The sensor can differentiate the motion characteristics of the positions and states of different joints with precise recognition (97.13%) with the assistance of machine learning algorithms. The unique integrated seamless structure is achieved by developing a layer-by-layer casting process that is suitable for large-scale manufacturing. The proposed wearable seamless multimode sensor and the convenient process are expected to contribute significantly to developing essential components in various emerging research fields, including soft robotics, electronic skin, health care, and innovative sports systems applications.

11.
J Appl Stat ; 48(8): 1475-1495, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35706467

RESUMEN

The order-of-addition experiment aims at determining the optimal order of adding components such that the response of interest is optimized. Order of addition has been widely involved in many areas, including bio-chemistry, food science, nutritional science, pharmaceutical science, etc. However, such an important study is rather primitive in statistical literature. In this paper, a thorough study on pair-wise ordering designs for order of addition is provided. The recursive relation between two successive full pair-wise ordering designs is developed. Based on this recursive relation, the full pair-wise ordering design can be obtained without evaluating all the orders of components. The value of the D-efficiency for the full pair-wise ordering model is then derived. It provides a benchmark for choosing the fractional pair-wise ordering designs. To overcome the unaffordability of the full pair-wise ordering design, a new class of minimal-point pair-wise ordering designs is proposed. A job scheduling problem as well as simulation studies are conducted to illustrate the performance of the pair-wise ordering designs for determining the optimal orders. It is shown that the proposed designs are very efficient in determining the optimal order of addition.

12.
J Exp Med ; 216(6): 1396-1410, 2019 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-31015298

RESUMEN

Induction of type I interferons (IFNs) is critical for eliciting competent immune responses, especially antiviral immunity. However, uncontrolled IFN production contributes to pathogenesis of autoimmune and inflammatory diseases. We found that transcription factor Hes1 suppressed production of type I IFNs and expression of IFN-stimulated genes. Functionally, Hes1-deficient mice displayed a heightened IFN signature in vivo, mounted enhanced resistance against encephalomyocarditis virus infection, and showed signs of exacerbated experimental lupus nephritis. Mechanistically, Hes1 did not suppress IFNs via direct transcriptional repression of IFN-encoding genes. Instead, Hes1 attenuated activation of TLR upstream signaling by inhibition of an adaptor molecule, WDFY1. Genome-wide assessment of Hes1 occupancy revealed that suppression of WDFY1 was secondary to direct binding and thus enhancement of expression of VEGF-C by Hes1, making Vegfc a rare example of an Hes1 positively regulated gene. In summary, these results identified Hes1 as a homeostatic negative regulator of type I IFNs for the maintenance of immune balance in the context of antiviral immunity and autoimmune diseases.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Interferón Tipo I/metabolismo , Factor de Transcripción HES-1/metabolismo , Factor C de Crecimiento Endotelial Vascular/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Inmunidad , Nefritis Lúpica/inmunología , Nefritis Lúpica/patología , Macrófagos/metabolismo , Ratones Endogámicos C57BL , Transducción de Señal , Porcinos , Receptor Toll-Like 3/metabolismo , Factor de Transcripción HES-1/deficiencia , Transcripción Genética , Factor C de Crecimiento Endotelial Vascular/genética
13.
Afr J Tradit Complement Altern Med ; 14(3): 274-279, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28480438

RESUMEN

BACKGROUND: Compound Arnebiae radix oil has been clinically applied to treat burns and scalds for a long time. However, it is unstable and inconvenient to use. The aim of this study was to prepare a compound Arnebiae radix microemulsion gel for transdermal delivery system and evaluate its characteristics. MATERIALS AND METHODS: Based on the solubility of Shikonin, the active component of Arnebiae radix and the results of phase studies, adequate ratio of each component in microemulsion was determined. The optimized microemulsion gel was prepared using Carbomer 940. The gels were characterized in terms of appearance, preliminary stability test and the content of Shikonin in the compound Arnebiae radix microemulsion gel with HPLC analysis. RESULTS: The optimized conditions for preparing microemulsion were Tween-80, glycerin, isopropyl myristate (IPM) with the ratio of 6:3:2. The optimal microemulsion gel was obtained with Carbomer 940 (1.0%). CONCLUSION: The prepared compound Arnebiae radix microemulsion gel showed good stability over time. It is more convenience in application than the previous used formulations.


Asunto(s)
Boraginaceae/química , Geles/síntesis química , Aceites de Plantas/química , Resinas Acrílicas , Química Farmacéutica/métodos , Estabilidad de Medicamentos , Emulsiones
14.
Drug Dev Ind Pharm ; 38(6): 653-8, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22468612

RESUMEN

AIM: The aim of this study was to investigate the feasibility of cationic biodegradable dextran microspheres loaded with bovine serum albumin (BSA) posterior to gel formation (postloading). METHOD: Positively charged microspheres were prepared by polymerization of hydroxylethyl methacrylate-derivatized dextran (dex-HEMA) and dimethyl aminoethyl methacrylate (DMAEMA) in an aqueous two-phase system and net positive surface charge increased with increasing amounts of DMAEMA. Loading efficiency of dextran microspheres for BSA was analyzed through fluorescence microscopy and measured. The BSA release from the cationic dextran microspheres in vitro was investigated. RESULTS: BSA could penetrate into cationic dextran microspheres, but neutral dextran microspheres could not. Protein-loading efficiency (98.1--100%) by postloading was higher compared with by preloading (60.2--75.9%), when the incubated protein concentration was below 1.5 mg/ml. Even though BSA is incorporated in the hydrogel network based on electrostatic interaction, a controlled release can be achieved by varying the initial network density of the microspheres. CONCLUSION: These findings suggest that it is a feasible method to prepare dextran microspheres with high surface-charge density to efficiently adsorb oppositely charged protein based on electrostatic interactions.


Asunto(s)
Implantes Absorbibles , Dextranos/química , Sistemas de Liberación de Medicamentos , Microesferas , Proteínas/química , Albúmina Sérica Bovina , Animales , Bovinos , Geles/química , Geles/metabolismo , Tamaño de la Partícula , Proteínas/metabolismo , Electricidad Estática , Propiedades de Superficie
15.
Yao Xue Xue Bao ; 45(9): 1183-7, 2010 Sep.
Artículo en Chino | MEDLINE | ID: mdl-21351577

RESUMEN

The aim of this study is to prepare cationic biodegradable dextran microspheres loaded with tetanus toxoid (TT) and to investigate the mechanism of protein loading. Positively charged microspheres were prepared by polymerization of hydroxylethyl methacrylate derivatized dextran (dex-HEMA) and dimethyl aminoethyl methacrylate (DMAEMA) in an aqueous two-phase system. The loading of the microspheres with TT was based on electrostatic attraction. The net positive surface charge increased with increasing amounts of DMAEMA. Confocal images showed fluorescein isothiocyanate labeled bovine serum albumin (FITC-BSA) could penetrate into cationic dextran microspheres but not natural dextran microspheres. TT loading efficiency by post-loading was higher compared with by pre-loading. Even though TT is incorporated in the hydrogel network based on electrostatic interaction, still a controlled release can be achieved by varying the initial network density of the microspheres.


Asunto(s)
Dextranos/química , Metacrilatos/química , Toxoide Tetánico/administración & dosificación , Preparaciones de Acción Retardada , Portadores de Fármacos/química , Hidrogeles/química , Microscopía Confocal , Microesferas , Tamaño de la Partícula , Polimerizacion , Albúmina Sérica Bovina/química , Toxoide Tetánico/química
16.
J Nanosci Nanotechnol ; 6(8): 2525-8, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17037867

RESUMEN

Cage-like nano-tetrapod ZnO is a novel structure, which was successfully synthesized by combustion oxidation at 850 degrees C. No catalyst or carrier gases were used. Thorough SEM and TEM analyses revealed that the linking legs of the tetrapod ZnO can have or not interface. The formation or not of an interface is discussed and it was attributed to different growth process of the cage-like ZnO nano-tetrapod. Enhanced UV emission peak at the wavelength of 375 nm, featuring high intensity and narrow width, indicates a highly crystalline structure. A green emission, recorded at 502 nm, was related to the defects of the surface of the branching configuration as well as to the ZnO nuclei of the cage-like nano-tetrapod ZnO.


Asunto(s)
Nanopartículas/química , Nanoestructuras/química , Nanotubos/química , Óxido de Zinc/química , Cristalografía por Rayos X , Luz , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Nanotecnología/métodos , Espectrofotometría Ultravioleta , Temperatura , Rayos Ultravioleta , Difracción de Rayos X
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...