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1.
Molecules ; 25(21)2020 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-33172169

RESUMEN

Pyrimidine is a privileged scaffold in many synthetic compounds exhibiting diverse pharmacological activities, and is used for therapeutic applications in a broad spectrum of human diseases. In this study, we prepared a small set of pyrimidine libraries based on the structure of two hit compounds that were identified through the screening of an in-house library in order to identify an inhibitor of anoctamin 1 (ANO1). ANO1 is amplified in various types of human malignant tumors, such as head and neck, parathyroid, and gastrointestinal stromal tumors, as well as in breast, lung, and prostate cancers. After initial screening and further structure optimization, we identified Aa3 as a dose-dependent ANO1 blocker. This compound exhibited more potent anti-cancer activity in the NCI-H460 cell line, expressing high levels of ANO1 compared with that in A549 cells that express low levels of ANO1. Our results open a new direction for the development of small-molecule ANO1 blockers composed of a pyrimidine scaffold and a nitrogen-containing heterocyclic moiety, with drug-like properties.


Asunto(s)
Anoctamina-1/antagonistas & inhibidores , Antineoplásicos/química , Antineoplásicos/farmacología , Proteínas de Neoplasias/antagonistas & inhibidores , Pirimidinas/química , Animales , Anoctamina-1/metabolismo , Antineoplásicos/síntesis química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Diseño de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Proteínas de Neoplasias/metabolismo , Pirimidinas/farmacología , Ratas
2.
Microsc Microanal ; 25(5): 1139-1154, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31387658

RESUMEN

The choice of materials that constitute electrodes and the way they are interconnected, i.e., the microstructure, influences the performance of lithium-ion batteries. For batteries with high energy and power densities, the microstructure of the electrodes must be controlled during their manufacturing process. Moreover, understanding the microstructure helps in designing a high-performance, yet low-cost battery. In this study, we propose a systematic algorithm workflow for the images of the microstructure of anodes obtained from a focused ion beam scanning electron microscope (FIB-SEM). Here, we discuss the typical issues that arise in the raw FIB-SEM images and the corresponding preprocessing methods that resolve them. Next, we propose a Fourier transform-based filter that effectively reduces curtain artifacts. Also, we propose a simple, yet an effective, global-thresholding method to identify active materials and pores in the microstructure. Finally, we reconstruct the three-dimensional structures by concatenating the segmented images. The whole algorithm workflow used in this study is not fully automated and requires user interactions such as choosing the values of parameters and removing shine-through artifacts manually. However, it should be emphasized that the proposed global-thresholding method is deterministic and stable, which results in high segmentation performance for all sectioning images.

3.
ACS Omega ; 3(1): 808-820, 2018 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-31457931

RESUMEN

For a solid acid-catalyzed dehydration of biomass-derived carbohydrates into useful furan derivatives, a suitable porous solid acid catalyst having an optimum acidic density and its strength is required to avoid cascade reactions in biomass conversion processes. A large-pore mesoporous zirconium phosphate (m-ZrP) was prepared hydrothermally using P123 as a template in water solvent, which resulted in a higher pore diameter (>9 nm) having wormhole-like pore structures with balanced Lewis (L) to Brönsted (B) acid sites. The effects of calcination temperature (500-800 °C) on the textural, acidic/basic, and structural properties of the m-ZrP with its catalytic performance for glucose dehydration to 5-hydroxymethylfurfural (HMF) were investigated in a pure water media as a green and sustainable alternative solvent. The larger number of L and B acid sites and basic sites with their appropriate strengths were clearly related with a better catalytic performance in terms of glucose conversion and HMF yield. The strong L acid and basic sites in the m-ZrP efficiently promoted the glucose isomerization to fructose, which dehydrated exclusively on the weak B acid sites resulting in a maximum conversion of glucose (83.8%) and HMF yield (46.6%). The adjusted acidic and basic sites with large mesopore sizes make the m-ZrP yield a higher reaction rate (2.78 mmol gcat -1 h-1) and turnover frequency (11.68/h) for conversion of glucose to HMF, which showed higher catalytic activity than those of a small-pore m-ZrP and other mesoporous heterogeneous and homogeneous acid catalysts.

4.
J Biomed Nanotechnol ; 13(1): 77-83, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29372998

RESUMEN

Argon plasma jet (Ar-PJ) has been widely used in clinical medicine; however, the cellular effects of Ar-PJ therapy applying to living tissues have not been clarified yet. It is necessary to investigate cellular responses to Ar-PJ in establishing guidelines on the therapeutic use of Ar-PJ. Interestingly, in the Ar-PJ-treated cells, the fragmented mitochondria, a typical cellular stress indicator, were discovered even in the cells located in the live zones (1∼3 zones). Using microscopic measurements of the mitochondrial length, we found that the fragmented mitochondria were mainly in the zones 1 and 2, the closest to the direct exposure point of Ar-PJ. Whereas, the mitochondria in the zone 4 retained their lengths to normal. This quantitative measurement of mitochondrial morphology was combined with the color scores of the polymerizable supramolecular (PS) sensor in diagnostic categories. The results demonstrate that the mitochondrial length (0.98∼3.94 µm) is inversely proportional to the PS sensor color scores (87∼0) in the zones 1∼4. On the combination of these three diagnostic parameters, the effective range of Ar-PJ for cellular responses was determined: the zones 1∼3, the color scores 87∼12 and the mitochondrial lengths 0.98∼2.57 µm. Our study is the first demonstration of mitochondrial fragmentation in response to Ar-PJ and the first attempt to establish the diagnostic guideline for Ar-PJ therapies by combinations with biological, physical and chemical aspects. Thus, this study will make great advances in the field of bioplasma applications.


Asunto(s)
Argón/farmacología , Colorimetría/métodos , Mitocondrias/efectos de los fármacos , Polímeros/química , Poliinos/química , Animales , Coagulación con Plasma de Argón , Células Cultivadas , Ratones , Ratones Endogámicos C57BL , Mitocondrias/patología , Polímero Poliacetilénico
5.
ACS Appl Mater Interfaces ; 8(37): 24482-90, 2016 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-27580340

RESUMEN

Protein binding and protein-induced nanoparticle aggregation are known to occur for a variety of nanomaterials, with the extent of binding and aggregation highly dependent on nanoparticle surface properties. However, often lacking are techniques that enable quantification of the extent of protein binding and aggregation, particularly for nanoparticles with polydisperse size distributions. In this study, we adapt ion mobility spectrometry (IMS) to examine the binding of bovine serum albumin to commercially available anionic-surfactant-coated superparamagnetic iron oxide nanoparticles (SPIONs), which are initially ∼21 nm in mean mobility diameter and have a polydisperse size distribution function (geometric standard deviation near 1.4). IMS, carried out with a hydrosol-to-aerosol converting nebulizer, a differential mobility analyzer, and a condensation particle counter, enables measurements of SPION size distribution functions for varying BSA/SPION number concentration ratios. IMS measurements suggest that initially (at BSA concentrations below 50 nM) BSA binds reversibly to SPION surfaces with a binding site density in the 0.05-0.08 nm(-2) range. However, at higher BSA concentrations, BSA induces SPION-SPION aggregation, evidenced by larger shifts in SPION size distribution functions (mean diameters beyond 40 nm for BSA concentrations near 100 nM) and geometric standard deviations (near 1.3) consistent with self-preserving aggregation theories. The onset of BSA aggregation is correlated with a modest but statistically significant decrease in the specific absorption rate (SAR) of SPIONs placed within an alternating magnetic field. The coating of SPIONs with mesoporous silica (MS-SPIONs) as well as PEGylation (MS-SPIONs-PEG) is found to completely mitigate BSA binding and BSA-induced aggregation; IMS-inferred size distribution functions are insensitive to BSA concentration for MS-SPIONs and MS-SPIONs-PEG. The SARs of MS-SPIONs are additionally insensitive to BSA concentration, confirming the SAR decrease is linked to BSA-induced aggregation.


Asunto(s)
Nanopartículas de Magnetita , Animales , Albúmina Sérica Bovina , Dióxido de Silicio , Propiedades de Superficie
6.
Nanoscale ; 8(35): 16053-64, 2016 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-27548050

RESUMEN

A promising route to cancer treatment is hyperthermia, facilitated by superparamagnetic iron oxide nanoparticles (SPIONs). After exposure to an alternating external magnetic field, SPIONs generate heat, quantified by their specific absorption rate (SAR, in W g(-1) Fe). However, without surface functionalization, commercially available, high SAR SPIONs (EMG 308, Ferrotec, USA) aggregate in aqueous suspensions; this has been shown to reduce SAR. Further reduction in SAR has been observed for SPIONs in suspensions containing cells, but the origin of this further reduction has not been made clear. Here, we use image analysis methods to quantify the structures of SPION aggregates in the extra- and intracellular milieu of LNCaP cell suspensions. We couple image characterization with nanoparticle tracking analysis and SAR measurements of SPION aggregates in cell-free suspensions, to better quantify the influence of cellular uptake on SPION aggregates and ultimately its influence on SAR. We find that in both the intra- and extracellular milieu, SPION aggregates are well-described by a quasifractal model, with most aggregates having fractal dimensions in the 1.6-2.2 range. Intracellular aggregates are found to be significantly larger than extracellular aggregates and are commonly composed of more than 10(3) primary SPION particles (hence they are "superaggregates"). By using high salt concentrations to generate such superaggregates and measuring the SAR of suspensions, we confirm that it is the formation of superaggregates in the intracellular milieu that negatively impacts SAR, reducing it from above 200 W g(-1) Fe for aggregates composed of fewer than 50 primary particles to below 50 W g(-1) for superaggregates. While the underlying physical mechanism by which aggregation leads to reduction in SAR remains to be determined, the methods developed in this study provide insight into how cellular uptake influences the extent of SPION aggregation, and enable estimation of the reduction of SAR brought about via uptake induced aggregation.


Asunto(s)
Compuestos Férricos , Nanopartículas de Magnetita , Línea Celular , Humanos , Campos Magnéticos
7.
Anal Chem ; 88(15): 7667-74, 2016 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-27373795

RESUMEN

Despite the importance of examining the formation of nanoparticle-protein conjugates, there is a dearth of routine techniques for nanoparticle-protein conjugate characterization. The most prominent change to a nanoparticle population upon conjugate formation is a shift in the nanoparticle size distribution function. However, commonly employed dynamic light scattering based approaches for size distribution characterization are ineffective for nonmonodisperse samples, and further they are relatively insensitive to size shifts of only several nanometers, which are common during conjugate formation. Conversely, gas phase ion mobility spectrometry (IMS) techniques can be used to reliably examine polydisperse samples, and are sensitive to ∼1 nm size distribution function shifts; the challenge with IMS is to convert nanoparticle-protein conjugates to aerosol particles without bringing about nonspecific aggregation or conjugate formation. Except in limited circumstances, electrospray based aerosolization has proven difficult to apply for this purpose. Here we show that via liquid nebulization (LN) with online, high-flow-rate dilution (with dilution factors up to 10 000) it is possible to aerosolize nanoparticle-protein conjugates, enabling IMS measurements of their conjugate size distribution functions. We specifically employ the LN-IMS system to examine bovine serum albumin binding to gold nanoparticles. Inferred maximum protein surface coverages (∼0.025 nm(-2)) from measurements are shown to be in excellent agreement with reported values for gold from quartz crystal microbalance measurements. It is also shown that LN-IMS measurements can be used to detect size distribution function shifts on the order of 1 nm, even in circumstances where the size distribution function itself has a standard deviation of ∼5 nm. In total, the reported measurements suggest that LN-IMS is a potentially simple and robust technique for nanoparticle-protein conjugate characterization.


Asunto(s)
Espectrometría de Movilidad Iónica , Nanopartículas del Metal/química , Albúmina Sérica Bovina/química , Animales , Bovinos , Oro/química , Concentración de Iones de Hidrógeno , Tamaño de la Partícula , Tecnicas de Microbalanza del Cristal de Cuarzo , Temperatura
8.
Analyst ; 141(4): 1363-75, 2016 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-26750519

RESUMEN

We apply liquid nebulization (LN) in series with ion mobility spectrometry (IMS, using a differential mobility analyzer coupled to a condensation particle counter) to measure the size distribution functions (the number concentration per unit log diameter) of gold nanospheres in the 5-30 nm range, 70 nm × 11.7 nm gold nanorods, and albumin proteins originally in aqueous suspensions. In prior studies, IMS measurements have only been carried out for colloidal nanoparticles in this size range using electrosprays for aerosolization, as traditional nebulizers produce supermicrometer droplets which leave residue particles from non-volatile species. Residue particles mask the size distribution of the particles of interest. Uniquely, the LN employed in this study uses both online dilution (with dilution factors of up to 10(4)) with ultra-high purity water and a ball-impactor to remove droplets larger than 500 nm in diameter. This combination enables hydrosol-to-aerosol conversion preserving the size and morphology of particles, and also enables higher non-volatile residue tolerance than electrospray based aerosolization. Through LN-IMS measurements we show that the size distribution functions of narrowly distributed but similarly sized particles can be distinguished from one another, which is not possible with Nanoparticle Tracking Analysis in the sub-30 nm size range. Through comparison to electron microscopy measurements, we find that the size distribution functions inferred via LN-IMS measurements correspond to the particle sizes coated by surfactants, i.e. as they persist in colloidal suspensions. Finally, we show that the gas phase particle concentrations inferred from IMS size distribution functions are functions of only of the liquid phase particle concentration, and are independent of particle size, shape, and chemical composition. Therefore LN-IMS enables characterization of the size, yield, and polydispersity of sub-30 nm particles.

9.
ACS Appl Mater Interfaces ; 8(3): 1813-8, 2016 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-26731170

RESUMEN

The fabrication of patterned conjugated polymer images on solid substrates has gained significant attention recently. Office inkjet printers can be used to generate flexible designs of functional materials on substrates on a large scale and in an inexpensive manner. Although creating patterns of conjugated polymers on paper using common office inkjet printers has been reported, only a few examples exist, such as polyaniline (PANI) and poly(3,4-ethylenedioxythiophene) (PEDOT), because only water-compatible inks can be utilized. Herein, we describe the production of poly(phenylenevinylene) (PPV) patterns on paper by employing a reactive inkjet printing (RIJ) method. In this process, printing of a hydrophilic terephthaldehyde, bis(triphenylphosphonium salt) and potassium t-butoxide using a common office inkjet printer leads to formation PPV patterns as a consequence of an in situ Wittig reaction. In addition, microarrayed PPV patterns are also readily generated on solid substrates, such as glass and PDMS, when a piezoelectric dispenser system is employed. The in situ prepared PPV was found to be insoluble in water and chloroform. As a result, unreacted excess reagents and byproducts can be efficiently removed by washing with these solvents.

10.
Technology (Singap World Sci) ; 2(3): 214-228, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25379513

RESUMEN

Aggregation is a known consequence of nanoparticle use in biology and medicine; however, nanoparticle characterization is typically performed under the pretext of well-dispersed, aqueous conditions. Here, we systematically characterize the effects of aggregation on the alternating magnetic field induced heating and magnetic resonance (MR) imaging performance of iron oxide nanoparticles (IONPs) in non-ideal biological systems. Specifically, the behavior of IONP aggregates composed of ~10 nm primary particles, but with aggregate hydrodynamic sizes ranging from 50 nm to 700 nm, was characterized in phosphate buffered saline and fetal bovine serum suspensions, as well as in gels and cells. We demonstrate up to a 50% reduction in heating, linked to the extent of aggregation. To quantify aggregate morphology, we used a combination of hydrodynamic radii distribution, intrinsic viscosity, and electron microscopy measurements to describe the aggregates as quasifractal entities with fractal dimensions in the 1.8-2.0 range. Importantly, we are able to correlate the observed decrease in magnetic field induced heating with a corresponding decrease in longitudinal relaxation rate (R1) in MR imaging, irrespective of the extent of aggregation. Finally, we show in vivo proof-of-principle use of this powerful new imaging method, providing a critical tool for predicting heating in clinical cancer hyperthermia.

11.
Colloids Surf B Biointerfaces ; 122: 851-856, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-25200202

RESUMEN

An essential requirement for continued technological advancement in many areas of biology, physics, chemistry, and materials science is the growing need to generate custom patterned materials. Building from recent achievements in the site-specific modification of virus for covalent surface tethering, we show in this work that stable 2D virus patterns can be generated in custom geometries over large area glass surfaces to yield templates of biological, biochemical, and inorganic materials in high density. As a nanomaterial building block, filamentous viruses have been extensively used in recent years to produce materials with interesting properties, owing to their ease of genetic and chemical modification. By utilizing un-natural amino acids generated at specific locations on the filamentous fd bacteriophage protein coat, surface immobilization is carried out on APTES patterned glass resulting in precise geometries of covalently linked virus material. This technique facilitated the surface display of a high density of virus that were labeled with biomolecules, fluorescent probes, and gold nanoparticles, thereby opening the possibility of integrating virus as functional components for surface engineering.


Asunto(s)
Compuestos Inorgánicos/química , Sondas Moleculares , Virus/química , Propiedades de Superficie
12.
Adv Mater ; 26(30): 5217-22, 2014 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-24942134

RESUMEN

Fabrication of 3D biological structures reveals dynamic response to external stimuli. A liquid-crystalline bridge extrusion technique is used to generate 3D structures allowing the capture of Rayleigh-like instabilities, facilitating customization of smooth, helical, or undulating periodic surface textures. By integrating intrinsic biochemical functionality and synthetic components into controlled structures, this strategy offers a new form of adaptable materials.


Asunto(s)
Bacteriófago M13/química , Bacteriófago M13/ultraestructura , Microfluídica/instrumentación , Microfluídica/métodos , Impresión Molecular/instrumentación , Impresión Molecular/métodos , Impresión Tridimensional/instrumentación , Bacteriófago M13/fisiología , Ensayo de Materiales , Propiedades de Superficie
13.
Nanotechnology ; 22(1): 015606, 2011 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-21135458

RESUMEN

A simple two step solution-based method was applied to fabricate CuO-ZnO heterostructured nanowire (NW) arrays. First, ZnO nanowires were grown on a Si substrate using the ammonia solution hydrothermal reaction. Afterwards, flower-like CuO crystals were photochemically deposited on the tip of the ZnO NWs, using ultraviolet (UV) light (312 nm wavelength) irradiation at room temperature. The morphology of the CuO was controlled by reaction time, density of ZnO NWs, and concentration of the solution. Because the deposited CuO is p-type and has narrow band gap properties, CuO-ZnO heterostructured NWs exhibited a stable p-n junction property and good ability to absorb visible light. Through investigation of UV light-triggered reaction phenomena, we found that the production of OH(-) from the photocatalytic process on the surface of ZnO NWs plays a critical role in the CuO deposition mechanism.

14.
J Immunol ; 185(11): 7037-46, 2010 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-20980634

RESUMEN

Galectin-3, a ß-galactoside-binding lectin, has been proposed to have multifaceted functions in various pathophysiological conditions. However, the characteristics of galectin-3 and its molecular mechanisms of action are still largely unknown. In this study, we show that galectin-3 exerts cytokine-like regulatory actions in rat and mouse brain-resident immune cells. Both the expression of galectin-3 and its secretion into the extracellular compartment were significantly enhanced in glia under IFN-γ-stimulated, inflamed conditions. After exposure to galectin-3, glial cells produced high levels of proinflammatory mediators and exhibited activated properties. Notably, within minutes after exposure to galectin-3, JAK2 and STAT1, STAT3, and STAT5 showed considerable enhancement of tyrosine phosphorylation; thereafter, downstream events of STAT signaling were also significantly enhanced. Treatment of the cells with pharmacological inhibitors of JAK2 reduced the galectin-3-stimulated increases of inflammatory mediators. Using IFN-γ receptor 1-deficient mice, we further found that IFN-γR 1 might be required for galectin-3-dependent activation of the JAK-STAT cascade. However, galectin-3 significantly induced phosphorylation of STATs in glial cells from IFN-γ-deficient mice, suggesting that IFN-γ does not mediate activation of STATs. Collectively, our findings suggest that galectin-3 acts as an endogenous danger signaling molecule under pathological conditions in the brain, providing a potential explanation for the molecular basis of galectin-3-associated pathological events.


Asunto(s)
Citocinas/fisiología , Galectina 3/fisiología , Janus Quinasa 2/fisiología , Factor de Transcripción STAT1/fisiología , Factor de Transcripción STAT3/fisiología , Transducción de Señal/inmunología , Animales , Astrocitos/inmunología , Astrocitos/metabolismo , Astrocitos/patología , Encefalopatías/inmunología , Encefalopatías/metabolismo , Encefalopatías/patología , Neoplasias Encefálicas/inmunología , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Células Cultivadas , Citocinas/biosíntesis , Citocinas/metabolismo , Galectina 3/biosíntesis , Galectina 3/metabolismo , Mediadores de Inflamación/metabolismo , Mediadores de Inflamación/fisiología , Interferón gamma/fisiología , Janus Quinasa 2/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Microglía/inmunología , Microglía/metabolismo , Microglía/patología , Fosforilación/inmunología , Ratas , Ratas Sprague-Dawley , Receptores de Interferón/deficiencia , Receptores de Interferón/genética , Factor de Transcripción STAT1/metabolismo , Factor de Transcripción STAT3/metabolismo , Receptor de Interferón gamma
15.
Korean J Physiol Pharmacol ; 13(4): 265-71, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19885009

RESUMEN

Nitric oxide (NO) has both neuroprotective and neurotoxic effects depending on its concentration and the experimental model. We tested the effects of NG-nitro-L-arginine methyl ester (L-NAME), a nonselective nitric oxide synthase (NOS) inhibitor, and aminoguanidine, a selective inducible NOS (iNOS) inhibitor, on kainic acid (KA)-induced seizures and hippocampal CA3 neuronal death. L-NAME (50 mg/kg, i.p.) and/or aminoguanidine (200 mg/kg, i.p.) were administered 1 h prior to the intracerebroventricular (i.c.v.) injection of KA. Pretreatment with L-NAME significantly increased KA-induced CA3 neuronal death, iNOS expression, and activation of microglia. However, pretreatment with aminoguanidine significantly suppressed both the KA-induced and L-NAME-aggravated hippocampal CA3 neuronal death with concomitant decreases in iNOS expression and microglial activation. The protective effect of aminoguanidine was maintained for up to 2 weeks. Furthermore, iNOS knockout mice (iNOS(-/-)) were resistant to KA-induced neuronal death. The present study demonstrates that aminoguanidine attenuates KA-induced neuronal death, whereas L-NAME aggravates neuronal death, in the CA3 region of the hippocampus, suggesting that NOS isoforms play different roles in KA-induced excitotoxicity.

16.
Chem Commun (Camb) ; (45): 7042-4, 2009 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-19904388

RESUMEN

A novel composite hierarchical hollow structure is reported. The as-prepared products consist of discrete WO(2) hollow core spheres with W(18)O(49) nanorod shells ("hollow urchins"). The products showed unusual magnetic behavior.

17.
Mol Cells ; 28(2): 119-24, 2009 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-19714313

RESUMEN

Anti cancer agent 5-FU (Fluoro Uracil) is a prodrug that can be metabolized and then activated to interfere with RNA and DNA homeostasis. However, the majority of administered 5-FU is known to be catabolized in vivo in the liver where Dihydropyrimidine dehydrogenase (DPD) is abundantly expressed to degrade 5-FU. The biological factors that correlate with the response to 5-FU-based chemotherapy have been proposed to include uridine phosphorylase (UPP), thymidine phosphorylase (TPP), p53 and microsatellite instability. Among these, the expression of UPP is known to be controlled by cytokines such as TNF-alpha, IL1 and IFN-gamma. Our preliminary study using a DNA microarray technique showed that basic fibroblast growth factor (bFGF) markedly induced the expression of UPP1 at the transcription level. In the present study, we investigated whether bFGF could modulate the expression of UPP1 in osteo-lineage cells and examined the sensitivity of these cells to 5-FU mediated apoptosis.


Asunto(s)
Apoptosis/efectos de los fármacos , Factor 2 de Crecimiento de Fibroblastos/farmacología , Fluorouracilo/farmacología , Regulación hacia Arriba/efectos de los fármacos , Uridina Fosforilasa/genética , Animales , Antimetabolitos Antineoplásicos/farmacología , Línea Celular , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Citometría de Flujo , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Humanos , Mioblastos/citología , Mioblastos/efectos de los fármacos , Mioblastos/metabolismo , Osteosarcoma/genética , Osteosarcoma/patología , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
18.
Biologicals ; 37(4): 203-9, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19264508

RESUMEN

Genetic modification of hematopoietic stem cells holds great promise in the treatment of hematopoietic disorders. However, clinical application of gene delivery has been limited, in part, by low gene transfer efficiency. To overcome this problem, we investigated the effect of retronectin (RN) on lentiviral-mediated gene delivery into hematopoietic progenitor cells (HPCs) derived from bone marrow both in vitro and in vivo. RN has been shown to enhance transduction by promoting colocalization of lentivirus and target cells. We found that RN enhanced lentiviral transfer of the VENUS transgene into cultured c-Kit(+) Lin(-) HPCs. As a complementary approach, in vivo gene delivery was performed by subjecting mice to intra-bone marrow injection of lentivirus or a mixture of RN and lentivirus. We found that co-injection with RN increased the number of VENUS-expressing c-Kit(+) Lin(-) HPCs in bone marrow by 2-fold. Further analysis of VENUS expression in colony-forming cells from the bone marrow of these animals revealed that RN increased gene delivery among these cells by 4-fold. In conclusion, RN is effective in enhancing lentivirus-mediated gene delivery into HPCs.


Asunto(s)
Fibronectinas/farmacología , Técnicas de Transferencia de Gen , Células Madre Hematopoyéticas/efectos de los fármacos , Lentivirus/genética , Proteínas Recombinantes/farmacología , Animales , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/metabolismo , Células Cultivadas , Evaluación Preclínica de Medicamentos , Fibronectinas/química , Células Madre Hematopoyéticas/metabolismo , Humanos , Lentivirus/fisiología , Ratones , Ratones Endogámicos C57BL , Células Madre Multipotentes/efectos de los fármacos , Células Madre Multipotentes/metabolismo , Fragmentos de Péptidos/farmacología , Estructura Terciaria de Proteína , Regulación hacia Arriba
19.
J Korean Med Sci ; 22(2): 380-2, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17449956

RESUMEN

Cervical spinal epidural abscess, caused by fish bone injury and a secondary infection by Eikenella corrodens which is part of the normal flora, has not been reported. A 72-yr-old man came to the hospital with pain in his posterior neck and both shoulders for 2 months. He also was experiencing weakness on his right side for 3 days. A fish bone had been stuck in his throat for about 2 months. Neurological examination revealed right hemiparesis, hypesthesia on the left extremities and neck stiffness. Laboratory findings showed an elevated ESR/CRP and leukocytosis, and magnetic resonance imaging revealed a retropharyngeal abscess and cervical myelitis. The patient was treated with emergency surgical decompression and antibiotics. A fish bone was removed from the C3-C4 intervertebral disc space. In the culture of chocolate blood agar and 5% sheep blood agar plate, E. corrodens was detected as a causative organism.


Asunto(s)
Eikenella corrodens/aislamiento & purificación , Absceso Epidural/etiología , Absceso Epidural/cirugía , Alimentos/efectos adversos , Cuerpos Extraños/complicaciones , Cuerpos Extraños/cirugía , Infecciones por Bacterias Gramnegativas/etiología , Anciano , Animales , Antibacterianos/administración & dosificación , Huesos , Descompresión Quirúrgica , Absceso Epidural/diagnóstico , Peces , Infecciones por Bacterias Gramnegativas/diagnóstico , Infecciones por Bacterias Gramnegativas/prevención & control , Humanos , Masculino
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