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1.
J Consult Clin Psychol ; 91(12): 744-749, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37616125

RESUMEN

OBJECTIVE: The potential prognostic role of emotion regulation in the treatment of major depressive disorder (MDD) has been highlighted by transtheoretical literature and supported by promising empirical findings. The majority of the literature is based on self-report observations at a single snapshot, thus little is known about the prognostic value of moment-to-moment dynamic evolvement of emotion. The present study is the first to examine the prognostic value of both intra- and interpersonal, moment-to-moment emotion regulation dynamics, and the potential moderating effect of the type of treatment. METHOD: To assess the prognostic value of emotion regulation dynamics, we focused on the first session, using 6,780 talk-turns within 52 patient-therapist dyads. Emotion regulation dynamics were measured using fundamental frequencies of the voice and were calculated using empirical Bayes residuals of the actor-partner interdependence model. Symptomatic change was measured using the Hamilton Rating Scale for Depression across 16 weeks of supportive treatment (ST) or supportive-expressive treatment (SET). RESULTS: Findings suggest that patients who show less regulated intrapersonal dynamics during the first session show less reduction of symptoms throughout treatment (ß = .26, p = .019). Findings further suggest that this association is mitigated when these patients receive SET, as opposed to ST (ß = .72, p = .020). CONCLUSIONS: The findings demonstrate the ability of first-session emotion regulation dynamics to serve as a prognostic variable. The findings further suggest that the adverse effect of emotion regulation dynamics on the patient's prognosis can be mitigated by explicit work on changing maladaptive emotional patterns. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Asunto(s)
Trastorno Depresivo Mayor , Regulación Emocional , Humanos , Regulación Emocional/fisiología , Trastorno Depresivo Mayor/terapia , Trastorno Depresivo Mayor/psicología , Pronóstico , Teorema de Bayes , Emociones/fisiología
2.
ACS Med Chem Lett ; 13(7): 1099-1108, 2022 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-35859861

RESUMEN

We describe the identification and characterization of a series of covalent inhibitors of the C-terminal kinase domain (CTKD) of MSK1. The initial hit was identified via a high-throughput screening and represents a rare example of a covalent inhibitor which acts via an SNAr reaction of a 2,5-dichloropyrimidine with a cysteine residue (Cys440). The covalent mechanism of action was supported by in vitro biochemical experiments and was confirmed by mass spectrometry. Ultimately, the displacement of the 2-chloro moiety was confirmed by crystallization of an inhibitor with the CTKD. We also disclose the crystal structures of three compounds from this series bound to the CTKD of MSK1, in addition to the crystal structures of two unrelated RSK2 covalent inhibitors bound to the CTKD of MSK1.

3.
Haematologica ; 105(6): 1641-1649, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31582538

RESUMEN

The cellular cytotoxicity of APY0201, a PIKfyve inhibitor, against multiple myeloma was initially identified in an unbiased in vitro chemical library screen. The activity of APY0201 was confirmed in all 25 cell lines tested and in 40% of 100 ex vivo patient-derived primary samples, with increased activity in primary samples harboring trisomies and lacking t(11;14). The broad anti-multiple myeloma activity of PIKfyve inhibitors was further demonstrated in confirmatory screens and showed the superior potency of APY0201 when compared to the PIKfyve inhibitors YM201636 and apilimod, with a mid-point half maximal effective concentration (EC50) at nanomolar concentrations in, respectively, 65%, 40%, and 5% of the tested cell lines. Upregulation of genes in the lysosomal pathway and increased cellular vacuolization were observed in vitro following APY0201 treatment, although these cellular effects did not correlate well with responsiveness. We confirm that PIKfyve inhibition is associated with activation of the transcription factor EB, a master regulator of lysosomal biogenesis and autophagy. Furthermore, we established an assay measuring autophagy as a predictive marker of APY0201 sensitivity. Overall, these findings indicate promising activity of PIKfyve inhibitors secondary to disruption of autophagy in multiple myeloma and suggest a strategy to enrich for likely responders.


Asunto(s)
Mieloma Múltiple , Autofagia , Humanos , Lisosomas , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/genética , Fosfatidilinositol 3-Quinasas/genética , Inhibidores de las Quinasa Fosfoinosítidos-3
4.
Sci Rep ; 9(1): 11670, 2019 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-31406177

RESUMEN

The glycolytic rate in neurons is low in order to allow glucose to be metabolized through the pentose-phosphate pathway (PPP), which regenerates NADPH to preserve the glutathione redox status and survival. This is controlled by 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase-3 (PFKFB3), the pro-glycolytic enzyme that forms fructose-2,6-bisphosphate, a powerful allosteric activator of 6-phosphofructo-1-kinase. In neurons, PFKFB3 protein is physiologically inactive due to its proteasomal degradation. However, upon an excitotoxic stimuli, PFKFB3 becomes stabilized to activate glycolysis, thus hampering PPP mediated protection of redox status leading to neurodegeneration. Here, we show that selective inhibition of PFKFB3 activity by the small molecule AZ67 prevents the NADPH oxidation, redox stress and apoptotic cell death caused by the activation of glycolysis triggered upon excitotoxic and oxygen-glucose deprivation/reoxygenation models in mouse primary neurons. Furthermore, in vivo administration of AZ67 to mice significantly alleviated the motor discoordination and brain infarct injury in the middle carotid artery occlusion ischemia/reperfusion model. These results show that pharmacological inhibition of PFKFB3 is a suitable neuroprotective therapeutic strategy in excitotoxic-related disorders such as stroke.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Fármacos Neuroprotectores/farmacología , Fosfofructoquinasa-2/genética , Piridinas/farmacología , Pirrolidinas/farmacología , Daño por Reperfusión/prevención & control , Células A549 , Animales , Isquemia Encefálica/genética , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patología , Corteza Cerebral/irrigación sanguínea , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/metabolismo , Corteza Cerebral/patología , Modelos Animales de Enfermedad , Inhibidores Enzimáticos/farmacología , Fructosadifosfatos/metabolismo , Regulación de la Expresión Génica , Ácido Glutámico/metabolismo , Ácido Glutámico/farmacología , Glucólisis/efectos de los fármacos , Humanos , Masculino , Ratones , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neuronas/patología , Vía de Pentosa Fosfato/efectos de los fármacos , Fosfofructoquinasa-1/genética , Fosfofructoquinasa-1/metabolismo , Fosfofructoquinasa-2/antagonistas & inhibidores , Fosfofructoquinasa-2/metabolismo , Cultivo Primario de Células , Complejo de la Endopetidasa Proteasomal/efectos de los fármacos , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteolisis/efectos de los fármacos , Desempeño Psicomotor/efectos de los fármacos , Daño por Reperfusión/genética , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología
5.
Sci Rep ; 6: 27264, 2016 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-27277521

RESUMEN

The interaction of light with matter strongly depends on the structure of the latter at wavelength scale. Ordered systems interact with light via collective modes, giving rise to diffraction. In contrast, completely disordered systems are dominated by Mie resonances of individual particles and random scattering. However, less clear is the transition regime in between these two extremes, where diffraction, Mie resonances and near-field interaction between individual scatterers interplay. Here, we probe this transitional regime by creating colloidal crystals with controlled disorder from two-dimensional self-assembly of bidisperse spheres. Choosing the particle size in a way that the small particles are transparent in the spectral region of interest enables us to probe in detail the effect of increasing positional disorder on the optical properties of the large spheres. With increasing disorder a transition from a collective optical response characterized by diffractive resonances to single particles scattering represented by Mie resonances occurs. In between these extremes, we identify an intermediate, hopping-like light transport regime mediated by resonant interactions between individual spheres. These results suggest that different levels of disorder, characterized not only by absence of long range order but also by differences in short-range correlation and interparticle distance, exist in colloidal glasses.

6.
Nat Biotechnol ; 34(1): 95-103, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26501955

RESUMEN

Despite the success of protein kinase inhibitors as approved therapeutics, drug discovery has focused on a small subset of kinase targets. Here we provide a thorough characterization of the Published Kinase Inhibitor Set (PKIS), a set of 367 small-molecule ATP-competitive kinase inhibitors that was recently made freely available with the aim of expanding research in this field and as an experiment in open-source target validation. We screen the set in activity assays with 224 recombinant kinases and 24 G protein-coupled receptors and in cellular assays of cancer cell proliferation and angiogenesis. We identify chemical starting points for designing new chemical probes of orphan kinases and illustrate the utility of these leads by developing a selective inhibitor for the previously untargeted kinases LOK and SLK. Our cellular screens reveal compounds that modulate cancer cell growth and angiogenesis in vitro. These reagents and associated data illustrate an efficient way forward to increasing understanding of the historically untargeted kinome.


Asunto(s)
Fosfotransferasas/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Glicosilación
7.
Nat Chem Biol ; 11(7): 525-31, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26006010

RESUMEN

Drugs with prolonged on-target residence times often show superior efficacy, yet general strategies for optimizing drug-target residence time are lacking. Here we made progress toward this elusive goal by targeting a noncatalytic cysteine in Bruton's tyrosine kinase (BTK) with reversible covalent inhibitors. Using an inverted orientation of the cysteine-reactive cyanoacrylamide electrophile, we identified potent and selective BTK inhibitors that demonstrated biochemical residence times spanning from minutes to 7 d. An inverted cyanoacrylamide with prolonged residence time in vivo remained bound to BTK for more than 18 h after clearance from the circulation. The inverted cyanoacrylamide strategy was further used to discover fibroblast growth factor receptor (FGFR) kinase inhibitors with residence times of several days, demonstrating the generalizability of the approach. Targeting of noncatalytic cysteines with inverted cyanoacrylamides may serve as a broadly applicable platform that facilitates 'residence time by design', the ability to modulate and improve the duration of target engagement in vivo.


Asunto(s)
Acrilamidas/farmacocinética , Linfocitos B/efectos de los fármacos , Cianoacrilatos/farmacocinética , Inhibidores de Proteínas Quinasas/farmacocinética , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Acrilamidas/síntesis química , Agammaglobulinemia Tirosina Quinasa , Animales , Linfocitos B/enzimología , Linfocitos B/patología , Línea Celular Tumoral , Cristalografía por Rayos X , Cianoacrilatos/síntesis química , Dasatinib , Femenino , Expresión Génica , Humanos , Ligandos , Simulación del Acoplamiento Molecular , Inhibidores de Proteínas Quinasas/síntesis química , Estructura Terciaria de Proteína , Proteínas Tirosina Quinasas/química , Proteínas Tirosina Quinasas/genética , Pirimidinas/farmacocinética , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Células Sf9 , Spodoptera , Relación Estructura-Actividad , Especificidad por Sustrato , Tiazoles/farmacocinética , Factores de Tiempo
8.
J Surg Res ; 175(1): 18-23, 2012 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-21962741

RESUMEN

INTRODUCTION: Trauma patients are at high risk of complications and death from coagulopathy and inflammatory organ failure. Recent evidence implicates protein C (PC) as a key mediator of this process. We hypothesized that a mutation in the PC gene would ameliorate the inflammatory and coagulopathic response to hemorrhagic shock (HS) and resuscitation. METHODS: FHH wild type and PC mutant rats underwent controlled hemorrhage for 120 min with 70% of blood volume removed. Rats were resuscitated with Ringers lactate (2x shed blood volume) and shed blood. Animals were sacrificed 4 h post-HS. Controls were untreated naïve rats. RESULTS: AST and NFkB lung protein levels were elevated similarly in both WT and mutants compared with naïve rats. Plasma fibrinogen levels decreased significantly with progression of HS compared with baseline (BL) levels and returned towards normal 4 h after resuscitation. PC activity was similar in both groups at BL (0.5 ± 0.08 versus 0.6 ± 0.14; P = 0.14) and decreased from BL by 53% ± 24% in WT (P =0.08), by 67% ± 11% in mutants (P = 0.03) at sacrifice, and was not different between groups (P = 0.29). CONCLUSIONS: Our model of HS and resuscitation produced a hypocoaguable, hyperinflammatory state with increased levels of NFkB and decreased levels of fibrinogen and PC levels. The mutated PC did not appear to alter these responses in our model of HS and resuscitation.


Asunto(s)
Coagulación Sanguínea/genética , Inflamación/genética , Proteína C/genética , Choque Hemorrágico/fisiopatología , Animales , Biomarcadores/análisis , Modelos Animales de Enfermedad , Fluidoterapia , Soluciones Isotónicas/uso terapéutico , Mutación , Ratas , Resucitación , Lactato de Ringer , Choque Hemorrágico/terapia
9.
Adv Mater ; 23(22-23): 2515-33, 2011 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-21594906

RESUMEN

We review the recently emerged class of hybrid metal-dielectric colloidal photonic crystals. The hybrid approach is understood as the combination of a dielectric photonic crystal with a continuous metal film. It allows to achieve a strong modification of the optical properties of photonic crystals by involving the light scattering at electronic excitations in the metal component into moulding of the light flow in series to the diffraction resonances occurring in the body of the photonic crystal. We consider different realizations of hybrid plasmonic-photonic crystals based on two- and three-dimensional colloidal photonic crystals in association with flat and corrugated metal films. In agreement with model calculations, different resonance phenomena determine the optical response of hybrid crystals leading to a broadly tuneable functionality of these crystals.


Asunto(s)
Coloides/química , Óptica y Fotónica , Cristalización , Metales/química , Modelos Moleculares , Resonancia por Plasmón de Superficie
10.
Transpl Immunol ; 24(4): 203-9, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21251981

RESUMEN

Conventional immunosuppressive therapies failed to prevent allograft chronic rejection. New approaches to modulate recipient immune response are needed. Donor-like MHC class I soluble proteins demonstrated therapeutic potential to suppress chronic rejection. The present study was designed to clarify the ability of MHC class I soluble proteins to induce T regulatory cells with true regulatory potential in a fully allogeneic rat cardiac transplant model. Donor-like MHC class I proteins upregulate small population of splenic CD8(-) negative CD4(+)CD25(+)FoxP3(+) positive cells. CD4(+) splenocytes after MHC therapy suppress lymphocyte proliferation against donor antigens in vitro. ACI recipients of WF hearts treated with CD4(+) cells, induced with donor-like MHC class I proteins (CD4-MHC), demonstrated stable survival of the transplanted organ (MST >120 days; n=17). Histology revealed that grafts of recipients treated with CD4-MHC had 23.6% vessels affected 100 days postgrafting. On the contrary, hearts obtained from long-term surviving hosts treated with CD4(+) cells induced with high-dose CsA (CD4-CsA) had 50-70% of affected vessels. CD4-MHC class I treated transplants were mostly CD3(-) negative, had low level of mast and FoxP3(+) cell infiltration compared to CD4-CsA treated hearts. Intragraft CD4(+) cells were close to mast cells in morphology. The same graft tissues had similar number of CD4(+) positive cells and mast cells suggesting existence of CD4(+) positive mast cells. On the other hand, a negligible number of FoxP3(+) positive cells in the grafts after CD4-MHC treatment supports the idea of CD4(+) positive FoxP3(+) negative mast cells population. We demonstrate that donor-like MHC class I protein therapy induces population of CD4(+)CD25(+)CD8(-)FoxP3(+) cells with potential to ameliorate development of transplant vascular disease and evoke CD4(+) positive FoxP3 negative mast cells in the secondary hosts.


Asunto(s)
Trasplante de Corazón , Antígenos de Histocompatibilidad Clase I/administración & dosificación , Inmunoterapia , Mastocitos/metabolismo , Linfocitos T Reguladores/metabolismo , Animales , Antígenos CD/biosíntesis , Células Cultivadas , Enfermedad Crónica , Factores de Transcripción Forkhead , Rechazo de Injerto/prevención & control , Activación de Linfocitos/efectos de los fármacos , Masculino , Mastocitos/efectos de los fármacos , Mastocitos/inmunología , Mastocitos/patología , Ratas , Ratas Endogámicas WF , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/patología
11.
Chem Res Toxicol ; 23(3): 578-90, 2010 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-20143881

RESUMEN

Exposure to environmental chemicals adds to the burden of disease in humans and wildlife to a degree that is difficult to estimate and, thus, mitigate. The ability to assess the impact of existing chemicals for which little to no toxicity data are available or to foresee such effects during early stages of chemical development and use, and before potential exposure occurs, is a pressing need. However, the capacity of the current toxicity evaluation approaches to meet this demand is limited by low throughput and high costs. In the context of EPA's ToxCast project, we have evaluated a novel cellular biosensor system (Factorial (1) ) that enables rapid, high-content assessment of a compound's impact on gene regulatory networks. The Factorial biosensors combined libraries of cis- and trans-regulated transcription factor reporter constructs with a highly homogeneous method of detection enabling simultaneous evaluation of multiplexed transcription factor activities. Here, we demonstrate the application of the technology toward determining bioactivity profiles by quantitatively evaluating the effects of 309 environmental chemicals on 25 nuclear receptors and 48 transcription factor response elements. We demonstrate coherent transcription factor activity across nuclear receptors and their response elements and that Nrf2 activity, a marker of oxidative stress, is highly correlated to the overall promiscuity of a chemical. Additionally, as part of the ToxCast program, we identify molecular targets that associate with in vivo end points and represent modes of action that can serve as potential toxicity pathway biomarkers and inputs for predictive modeling of in vivo toxicity.


Asunto(s)
Técnicas Biosensibles/métodos , Contaminantes Ambientales/efectos adversos , Receptores Citoplasmáticos y Nucleares/genética , Factores de Transcripción/genética , Transcripción Genética/efectos de los fármacos , Animales , Técnicas Biosensibles/economía , Técnicas Biosensibles/instrumentación , Células Hep G2 , Conejos , Ratas , Elementos de Respuesta/efectos de los fármacos
12.
Mol Immunol ; 46(11-12): 2256-66, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19477016

RESUMEN

The beta(3)-adrenergic receptor (beta(3)AR) is an essential regulator of metabolic and endocrine functions. A major cellular and clinically significant consequence of beta(3)AR activation is the substantial elevation in interleukin-6 (IL-6) levels. Although the beta(3)AR-dependent regulation of IL-6 expression is well established, the cellular pathways underlying this regulation have not been characterized. Using a novel method of homogenous reporters, we assessed the pattern of activation of 43 transcription factors in response to the specific beta(3)AR agonist CL316243 in adipocytes, cells that exhibit the highest expression of beta(3)ARs. We observed a unique and robust activation of the CRE-response element, suggesting that IL-6 transcription is regulated via the G(s)-protein/cAMP/protein kinase A (PKA) but not nuclear factor kappa B (NF-kappaB) pathway. However, pretreatment of adipocytes with pharmacologic inhibitors of PKA pathway failed to block beta(3)AR-mediated IL-6 up-regulation. Additionally, stimulation of adipocytes with the exchange protein directly activated by cAMP (Epac) agonist did not induce IL-6 expression. Instead, the beta(3)AR-mediated transcription of IL-6 required activation of both the p38 and PKC pathways. Western blot analysis further showed that transcription factors CREB and ATF-2 but not ATF-1 were activated in a p38- and PKC-dependent manner. Collectively, our results suggest that while stimulation of the beta(3)AR leads to a specific activation of CRE-dependent transcription, there are several independent cellular pathways that converge at the level of CRE-response element activation, and in the case of IL-6 this activation is mediated by p38 and PKC but not PKA pathways.


Asunto(s)
Adipocitos Blancos/metabolismo , Interleucina-6/biosíntesis , Receptores Adrenérgicos beta 3/fisiología , Factor de Transcripción Activador 1/metabolismo , Adipocitos Blancos/citología , Agonistas de Receptores Adrenérgicos beta 3 , Animales , Diferenciación Celular/fisiología , Línea Celular , AMP Cíclico/fisiología , Proteínas Quinasas Dependientes de AMP Cíclico/fisiología , Dioxoles/farmacología , Subunidades alfa de la Proteína de Unión al GTP Gs/fisiología , Regulación de la Expresión Génica , Humanos , Ratones , FN-kappa B/fisiología , Proteína Quinasa C/fisiología , Elementos de Respuesta , Transducción de Señal , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
13.
Opt Lett ; 34(10): 1519-21, 2009 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-19448807

RESUMEN

Transformation of broadband emission of oxygen defects in the carcass of ZnO-inverted opal into a multiple-mode amplified spontaneous emission band has been observed in the spectral interval of a photonic bandgap upon increasing excitation intensity. The mode structure has been assigned to amplification of emission coupled to resonance modes of the self-selected distributed Bragg resonator. The surprisingly low 2 W/cm(2) onset of amplification has been explained by the long radiative decay time of defect states populated according to the three-level excitation scheme. The decrease of emission intensity between amplified peaks has been associated with the saturation of the ZnO defect emission.

14.
Opt Express ; 17(8): 5925-32, 2009 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-19365411

RESUMEN

We model and optimize the excitation of a plasmonic gap waveguide by a dipole antenna. The coupling efficiency strongly depends on antenna and waveguide properties where impedance matching plays a critical role. The optimization of antenna lengths and gap widths shows that concepts of circuit networks can likewise be applied to optical frequencies. Using classical optimization schemes known from electrical engineering we manage to increase the coupling efficiency by a factor of 129 compared with the situation without antennas.


Asunto(s)
Diseño Asistido por Computadora , Modelos Teóricos , Nanotecnología/instrumentación , Resonancia por Plasmón de Superficie/instrumentación , Simulación por Computador , Diseño de Equipo , Análisis de Falla de Equipo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
15.
Angew Chem Int Ed Engl ; 47(35): 6538-49, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18666276

RESUMEN

Colloidal semiconductor nanocrystals are promising luminophores for creating a new generation of electroluminescence devices. Research on semiconductor nanocrystal based light-emitting diodes (LEDs) has made remarkable advances in just one decade: the external quantum efficiency has improved by over two orders of magnitude and highly saturated color emission is now the norm. Although the device efficiencies are still more than an order of magnitude lower than those of the purely organic LEDs there are potential advantages associated with nanocrystal-based devices, such as a spectrally pure emission color, which will certainly merit future research. Further developments of nanocrystal-based LEDs will be improving material stability, understanding and controlling chemical and physical phenomena at the interfaces, and optimizing charge injection and charge transport.

16.
Opt Lett ; 33(5): 461-3, 2008 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-18311292

RESUMEN

A change of up to 40% of the relative transmission at the photonic bandgap edge has been observed in photoconductive inverted ZnO opals under ultraviolet laser irradiation. This effect has been related to the irradiation-stimulated change of the refraction index of the photonic crystal. The desorption (chemosorption) of oxygen molecules on the surface of the ZnO backbone leading to destruction (formation) of a depletion layer at the ZnO surface has been suggested as the mechanism responsible for the slow variation of polarizability of the inverted ZnO opal.

17.
Nat Methods ; 5(3): 253-60, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18297081

RESUMEN

We developed a high-content reporter system that allows quantitative assessment of activities of multiple transcription factors (TFs) in a eukaryotic cell. The system comprises a library of reporter constructs that are evaluated according to their transcription rates. All reporters produce essentially identical messages that are subjected to 'processing', which generates a spectrum of distinguishable fragments that are analyzed quantitatively. The homogeneity of the reporter library afforded inherently uniform detection conditions for all reporters and provided repeatability, accuracy and robustness of assessment. We showed that this technology can be used to identify pathways transmitting cell responses to inducers, and that the profile of TF activities generated using this system represents a stable and sustained cell signature that clearly distinguishes different cell types and pathological conditions. This technology provides a framework for functional characterization of signal transduction networks through profiling activities of multiple TFs.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Biblioteca de Genes , Genes Reporteros/fisiología , Factores de Transcripción/genética , Animales , Carbazoles/farmacología , Línea Celular Tumoral , Colforsina/farmacología , Humanos , Indoles/farmacología , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Reacción en Cadena de la Polimerasa , Ratas , Receptores de Hidrocarburo de Aril/efectos de los fármacos , Reproducibilidad de los Resultados , Transfección/métodos , Factor de Crecimiento Transformador beta/farmacología
18.
Langmuir ; 22(17): 7378-83, 2006 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-16893241

RESUMEN

We report on the fabrication of high-quality opaline photonic crystals from large silica spheres (diameter of 890 nm), self-assembled in hydrophilic trenches of silicon wafers by using a novel technique coined a combination of "lifting and stirring". The achievements reported here comprise a spatial selectivity of opal crystallization without special treatment of the wafer surface, a filling of the trenches up to the top, leading to a spatially uniform film thickness, particularly an absence of cracks within the size of the trenches, and finally a good 3D order of the opal lattice even in trenches with a complex confined geometry, verified using optical measurements. The opal lattice was found to match the pattern precisely in width as well as depth, providing an important step toward applications of opals in integrated optics.

19.
J Leukoc Biol ; 78(6): 1366-77, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16204640

RESUMEN

The transcription factor nuclear factor (NF)-kappaB controls the expression of genes involved in inflammation, cell proliferation, apoptosis, and differentiation. Impaired regulation of NF-kappaB has been associated with many diseases; thus, there is significant interest in therapeutic approaches based on modulation of this transcription factor. NF-kappaB activity is controlled by numerous signaling molecules, many of which are potentially to be identified. Monocytes are principal effectors of the immune system, and monocyte adherence is the first step leading to their activation and differentiation. Adherence induces activation of NF-kappaB, resulting in the induction of proinflammatory genes as well as anti-inflammatory genes, which counterbalance and limit the intensity and duration of NF-kappaB activation. Here, to identify novel mediators of NF-kappaB signaling, we used the model of monocyte adherence to perform a systematic, genome-wide survey of adherence-induced genes. Having isolated mRNAs from nonadherent and adherent primary human monocytes, we constructed suppressive subtraction hybridization libraries containing cDNAs, which were differentially regulated by adherence. Of 366 identified differentially expressed genes, most were found to be up-regulated by adherence. Having analyzed a subset of these genes, we found that the library was enriched with inhibitors of NF-kappaB. Three of those (an orphan nuclear receptor NUR77, a guanosine 5'-diphosphate/guanosine 5'-triphosphate exchange factor RABEX5, and a PRK1-associated protein AWP1) were particularly potent inhibitors of NF-kappaB activation. Thus, the collection of monocyte adherence-regulated genes represents a rich source for the identification of novel components of the machinery that controls NF-kappaB activation.


Asunto(s)
Quimiotaxis de Leucocito/genética , Regulación de la Expresión Génica/genética , Genoma/genética , Inflamación/genética , Monocitos/metabolismo , FN-kappa B/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Adhesión Celular/genética , Células Cultivadas , Quimiotaxis de Leucocito/inmunología , Proteínas de Unión al ADN/genética , Perfilación de la Expresión Génica , Genes/genética , Biblioteca Genómica , Factores de Intercambio de Guanina Nucleótido/genética , Humanos , Inflamación/inmunología , FN-kappa B/genética , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares , Receptores Citoplasmáticos y Nucleares/genética , Receptores de Esteroides/genética , Transducción de Señal/genética , Transducción de Señal/inmunología , Factores de Transcripción/genética , Regulación hacia Arriba/genética
20.
Small ; 1(1): 122-30, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17193362

RESUMEN

Metallodielectric inverse opals were prepared by co-crystallizing silica-coated gold nanoparticles and polymer spheres, followed by removal of the crystal template. The inverse opals exhibit a distinct reflectance peak, which results from Bragg diffraction due to the highly ordered 3D macroporous structure. Photonic band-structure calculations indicate that the characteristic reflectance peaks observed are signatures of the directional gap at the L point. It is demonstrated that the optical properties (the position and magnitude of the electromagnetic bandgaps) of the gold-silica nanocomposite inverse opals can be engineered by varying the nanoparticle morphology (core size and shell thickness) and/or the nanoparticle volume-filling ratio of the composite. The use of metallodielectric nanoparticles to form inverse opals offers a versatile approach to prepare photonic materials that may exhibit absolute bandgaps.


Asunto(s)
Ensayo de Materiales , Nanopartículas del Metal/química , Cristalización , Oro/química , Nanopartículas del Metal/ultraestructura , Microscopía Electrónica de Rastreo , Modelos Químicos , Óptica y Fotónica , Polímeros/química , Dióxido de Silicio/química
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