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1.
Sci Rep ; 12(1): 10437, 2022 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-35729322

RESUMEN

Dysregulation of ion flux across membranes and glutamate-induced excitotoxicity appear to be important pathophysiologic abnormalities in bipolar illness. Understanding ion control and responses to ionic stress is important to decipher the pathogenesis of this disorder. Monensin alone significantly increased [Na]i in ONPs from bipolar individuals (5.08 ± 0.71 vs baseline 3.13 ± 0.93, P = 0.03) and AP5 had no effect (2.0 ± 1.2 vs baseline 3.13 ± 0.93, P = 0.27). However, the combination of AP5 and monensin resulted in normalization of [Na]i (3.25 ± 1.28 vs baseline 3.13 ± 0.93, P = 0.89). This effect was not observed in cells from non-bipolar individuals (monensin alone, 1.72 ± 1.10 vs baseline 2.42 ± 1.80, P = 0.25; AP5 alone, 1.37 ± 0.74 vs baseline 2.42 ± 1.80; AP5 combined with monensin, 1.53 ± 0.98 vs baseline 2.42 ± 1.80, P = 0.31). Sodium regulation is central to neuronal function and may be disturbed in patients with bipolar disorder. Monensin is an ionophore, meaning that it incorporates itself into the membrane and allows sodium to enter independent of cellular membrane proteins. While the mechanism remains obscure, the observation that the NMDA receptor antagonist, AP5, normalizes [Na]i only in olfactory neuroepithelial precursors obtained from bipolar illness may provide novel insights into ion regulation in tissues from subjects with bipolar illness.


Asunto(s)
Trastorno Bipolar , Sodio , Trastorno Bipolar/tratamiento farmacológico , Humanos , Ionóforos/farmacología , Iones/metabolismo , Monensina/farmacología , Receptores de N-Metil-D-Aspartato/fisiología , Sodio/metabolismo
2.
Eng Life Sci ; 21(7): 502-513, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34257631

RESUMEN

There is a growing need to provide effective adventitious agent mitigation for high risk upstream cell culture raw materials used for the production of biologics. It is also highly important in the growing fields of cell and gene therapies. Glucose is a critical raw material necessary for effective cell growth and productivity; however, glucose is the highest risk animal-origin-free raw material for viral contamination, and often the highest risk raw material in the upstream process as more companies move to chemically defined media. This study examines the efficacy of utilizing High Temperature Short Time (HTST) pasteurization for inactivation of physiochemically resistant, worst-case parvovirus using a bench-scale HTST system. We demonstrated approximately six log inactivation of Minute Virus of Mice (MVM) in concentrated glucose feeds without impacting the subsequent performance of the glucose in a Chinese Hamster Ovary (CHO) expression system.

3.
Neurosci Biobehav Rev ; 107: 208-214, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31521699

RESUMEN

BACKGROUND: Accurate modeling of psychiatric disorders in animals is essential for advancement in our understanding and treatment of the severe mental illnesses. Of the multiple models available for bipolar illness, the ones that disrupt ion flux are currently the only ones that meet the three criteria for validity: face validity, construct validity, and predictive validity. METHODS: A directed review was performed to evaluate animal models for mania in which ion dysregulation was the key intervention. RESULTS: Three models are identified. All focus on disruption of the sodium potassium pump. One is pharmacologic and requires surgical insertion of an intracerebroventricular (ICV) cannula and subsequent administration of ouabain. Two are genetic and are based on heterozygote knockout (KO) of the alpha2 or alpha3 subunits of the sodium pump. Alpha2 KOs are believed to have altered glial function, and they do not appear to have a full array of manic symptoms. Alpha3 KOs appear to be the best characterized animal model for bipolar disorder currently available. CONCLUSION: Animal models that disrupt ion regulation are more inclined to model both mania and depression; and are thus the most promising models available. However, other models are important for demonstrating mechanisms in important pathophysiologic aspect of bipolar disorder.


Asunto(s)
Trastorno Bipolar/genética , Modelos Animales de Enfermedad , Canales Iónicos/genética , Animales , Trastorno Bipolar/metabolismo , Canales Iónicos/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/genética , ATPasa Intercambiadora de Sodio-Potasio/metabolismo
4.
Stem Cell Rev Rep ; 15(4): 497-505, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31020518

RESUMEN

Recent evidence indicates that the occurrence of psychiatric disorders in patients is linked to a local "sterile" inflammation of brain or due to a systemic inflammation process that affects the central nervous system. This is supported by the observation that in peripheral blood of psychotic patients are detectable several mediators and markers of inflammation as well as clinical data on correlations between systemic chronic inflammatory processes and psychiatric disorders. This may explain why some reported anti-inflammatory treatment strategies have beneficial effects on ameliorating psychotic events. In this review we will present a concept that aberrant purinergic signaling and increases in extracellular level of adenosine triphosphate (ATP) in the brain parenchyma may lead to activation of Nlrp3 inflammasome in microglia cells and as a consequence microglia released danger associated molecular pattern (DAMP) proteins activate complement cascade (ComC) in mannan binding lectin (MBL) - dependent manner. Activation of ATP-Nlrp3 inflammasome-ComC axis may also orchestrate trafficking of stem cells released from bone marrow into peripheral blood observed in psychotic patients. Based on this, the ATP-Nlrp3 inflammasome-ComC axis may become a target for new therapeutic approaches, which justifies the development and clinical application of efficient anti-inflammatory treatment strategies targeting this axis in psychiatry.


Asunto(s)
Adenosina Trifosfato/metabolismo , Encéfalo/metabolismo , Movimiento Celular , Proteínas del Sistema Complemento/metabolismo , Inflamasomas/metabolismo , Trastornos Mentales/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Células Madre/metabolismo , Encéfalo/patología , Activación de Complemento , Humanos , Inflamación/metabolismo , Inflamación/patología , Trastornos Mentales/patología , Células Madre/patología
5.
Stem Cell Rev Rep ; 15(4): 601-611, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30835047

RESUMEN

Despite considerable advances made in understanding of lung cancer biology, there has been meek improvement in lung cancer treatment outcome with 4% to 5% increase in 5-year survival rates in the last four decades. Underlying problem of lung cancer recurrence and poor prognosis is attributed to the presence of cancer stem cells (CSCs) which possess the potential to differentiate, proliferate and trigger chemo-resistance, tumor progression and metastasis, despite initial elimination of the tumor. To address specific targeting of CSCs, we investigated the effects of a small molecule Verrucarin J (VJ) on lung cancer cell lines A549 and H1793. VJ significantly inhibited cell proliferation of both cell lines, with IC50 values of approximately 10 nM for A549 and 20 nM for H1793 respectively after 48 h of treatment. A549 cell line when treated with VJ, induced cell apoptosis with concomitant down regulation of key CSC specific genes- ALDH1, LGR5, OCT4 and CD133 in a dose-dependent manner. To delineate the molecular mechanism by which VJ targets lung cancer cells and CSCs, we determined the effects of VJ on CSC self-renewal pathways Wnt1/ß-catenin and Notch1. Treatment of A549 cell line with VJ inhibited significantly both the signalling pathways, suggesting inhibition of expression of CSC genes by VJ through the inhibition of CSC self-renewal signalling pathways. Taken together, our results suggest that VJ may serve as a potent anticancer drug to target cancer cells and CSCs.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias Pulmonares/tratamiento farmacológico , Proteínas de Neoplasias/biosíntesis , Células Madre Neoplásicas/metabolismo , Células A549 , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Células Madre Neoplásicas/patología , Tricotecenos/farmacología
6.
Leukemia ; 33(4): 1058, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30842606

RESUMEN

The original version of this Article omitted the following from the Acknowledgements.

7.
Leukemia ; 32(12): 2519-2526, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30375490

RESUMEN

Tumorigenesis can be considered as pathologically misappropriated tissue regeneration. In this review we will address some unresolved issues that support this concept. First, we will address the issue of the identity of cancer-initiating cells and the presence of cancer stem cells in growing tumors. We will also ask are there rare and distinct populations of cancer stem cells in established tumor cell lines, or are all of the cells cancer stem cells? Second, the most important clinical problem with cancer is its metastasis, and here a challenging question arises: by employing radio-chemotherapy for tumor treatment, do we unintentionally create a prometastatic microenvironment in collateral organs? Specifically, many factors upregulated in response to radio-chemotherapy-induced injury may attract highly migratory cancer cells that survived initial treatment. Third, what is the contribution of normal circulating stem cells to the growing malignancy? Do circulating normal stem cells recognize a tumor as a hypoxia-damaged tissue that needs vascular and stromal support and thereby contribute to tumor expansion? Fourth, is it reasonable to inhibit only one prometastatic ligand-receptor axis when cancer stem cells express several receptors for several chemotactic factors that may compensate for inhibition of the targeted receptor? Fifth, since most aggressive cancer cells mimic early-development stem cells, which properties of embryonic stem cells are retained in cancer cells? Would it be reasonable to inhibit cancer cell signaling pathways involved in the migration and proliferation of embryonic stem cells? We will also briefly address some new players in cancerogenesis, including extracellular microvesicles, bioactive phospholipids, and extracellular nucleotides.


Asunto(s)
Neoplasias/patología , Células Madre Neoplásicas/patología , Regeneración/fisiología , Animales , Carcinogénesis/genética , Carcinogénesis/metabolismo , Carcinogénesis/patología , Movimiento Celular/genética , Movimiento Celular/fisiología , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Células Madre Neoplásicas/metabolismo , Regeneración/genética , Transducción de Señal/genética , Transducción de Señal/fisiología , Microambiente Tumoral/genética , Microambiente Tumoral/fisiología , Regulación hacia Arriba/genética , Regulación hacia Arriba/fisiología
8.
J Control Release ; 194: 113-21, 2014 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-25180449

RESUMEN

There is an unmet clinical need to increase lung transplant successes, patient satisfaction and to improve mortality rates. We offer the development of a nanovector-based solution that will reduce the incidence of lung ischemic reperfusion injury (IRI) leading to graft organ failure through the successful ex vivo treatment of the lung prior to transplantation. The innovation is in the integrated application of our novel porous silicon (pSi) microparticles carrying adeno-associated virus (AAV) nanoparticles, and the use of our ex vivo lung perfusion/ventilation system for the modulation of pro-inflammatory cytokines initiated by ischemic pulmonary conditions prior to organ transplant that often lead to complications. Gene delivery of anti-inflammatory agents to combat the inflammatory cascade may be a promising approach to prevent IRI following lung transplantation. The rationale for the device is that the microparticle will deliver a large payload of virus to cells and serve to protect the AAV from immune recognition. The microparticle-nanoparticle hybrid device was tested both in vitro on cell monolayers and ex vivo using either porcine venous tissue or a pig lung transplantation model, which recapitulates pulmonary IRI that occurs clinically post-transplantation. Remarkably, loading AAV vectors into pSi microparticles increases gene delivery to otherwise non-permissive endothelial cells.


Asunto(s)
Vasos Sanguíneos/metabolismo , Dependovirus/inmunología , Técnicas de Transferencia de Gen , Nanopartículas/química , Silicio/química , Animales , Vasos Sanguíneos/citología , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Expresión Génica , Humanos , Pulmón/inmunología , Pulmón/metabolismo , Pulmón/virología , Tamaño de la Partícula , Porcinos , Venas/inmunología , Venas/virología
9.
Nanomedicine (Lond) ; 9(5): 581-592, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23731456

RESUMEN

AIMS: Endothelial cells are dynamic cells tasked with selective transport of cargo from blood vessels to tissues. Here we demonstrate the potential for nanoparticle transport across endothelial cells in membrane-bound vesicles. MATERIALS & METHODS: Cell-free endothelial-derived biovesicles were characterized for cellular and nanoparticle content by electron microscopy. Confocal microscopy was used to evaluate biovesicles for organelle-specific proteins, and to monitor biovesicle engulfment by naive cells. RESULTS: Nanoparticle-laden biovesicles containing low-density polyethyleneimine nanoparticles appear to be predominately of endosomal origin, combining features of multivesicular bodies, lysosomes and autophagosomes. Conversely, high-density polyethyleneimine nanoparticles stimulate the formation of biovesicles associated with cellular apoptotic breakdown. Secreted LAMP-1-positive biovesicles are internalized by recipient cells, either of the same origin or of novel phenotype. CONCLUSION: Cellular biovesicles, rich in cellular signals, present an important mode of cell-to-cell communication either locally or through broadcasting of biological messages.


Asunto(s)
Comunicación Celular/fisiología , Endosomas/química , Células Endoteliales/química , Células Endoteliales/fisiología , Nanopartículas/química , Nanopartículas/ultraestructura , Vesículas Transportadoras/química , Materiales Biomiméticos/química , Sistema Libre de Células/química , Células Cultivadas , Humanos , Tamaño de la Partícula
10.
Methods Enzymol ; 508: 1-16, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22449918

RESUMEN

Logic-embedded vectors (LEVs) have been introduced as a means to overcome sequential, biological barriers that prevent particle-based drug delivery systems from reaching their targets. In this chapter, we address the challenge of fabricating and optimizing LEVs to reach non-endosomal targets. We describe the general preparation, characterization, and cellular association of porous silicon-based LEVs. A specific example of LEV fabrication from start to finish, along with optimization and troubleshooting information, is presented to serve as a template for future designs.


Asunto(s)
Sistemas de Liberación de Medicamentos , Silicio/química , Quitosano/química , Portadores de Fármacos , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie
11.
Mol Imaging ; 10(1): 43-55, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21303614

RESUMEN

Mass transport of drug delivery vehicles is guided by particle properties, such as size, shape, composition, and surface chemistry, as well as biomolecules and serum proteins that adsorb to the particle surface. In an attempt to identify serum proteins influencing cellular associations and biodistribution of intravascularly injected particles, we used two-dimensional gel electrophoresis and mass spectrometry to identify proteins eluted from the surface of cationic and anionic silicon microparticles. Cationic microparticles displayed a 25-fold greater abundance of Ig light variable chain, fibrinogen, and complement component 1 compared to their anionic counterparts. Anionic microparticles were found to accumulate in equal abundance in murine liver and spleen, whereas cationic microparticles showed preferential accumulation in the spleen. Immunohistochemistry supported macrophage uptake of both anionic and cationic microparticles in the liver, as well as evidence of association of cationic microparticles with hepatic endothelial cells. Furthermore, scanning electron micrographs supported cellular competition for cationic microparticles by endothelial cells and macrophages. Despite high macrophage content in the lungs and tumor, microparticle uptake by these cells was minimal, supporting differences in the repertoire of surface receptors expressed by tissue-specific macrophages. In summary, particle surface chemistry drives selective binding of serum components impacting cellular interactions and biodistribution.


Asunto(s)
Portadores de Fármacos/metabolismo , Proteínas Opsoninas/sangre , Silicio/química , Animales , Portadores de Fármacos/química , Electroforesis en Gel Bidimensional , Espectrometría de Masas , Ratones , Porosidad
12.
Small ; 6(23): 2691-700, 2010 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-20957619

RESUMEN

A new generation of nanocarriers, logic-embedded vectors (LEVs), is endowed with the ability to localize components at multiple intracellular sites, thus creating an opportunity for synergistic control of redundant or dual-hit pathways. LEV encoding elements include size, shape, charge, and surface chemistry. In this study, LEVs consist of porous silicon nanocarriers, programmed for cellular uptake and trafficking along the endosomal pathway, and surface-tailored iron oxide nanoparticles, programmed for endosomal sorting and partitioning of particles into unique cellular locations. In the presence of persistent endosomal localization of silicon nanocarriers, amine-functionalized nanoparticles are sorted into multiple vesicular bodies that form novel membrane-bound compartments compatible with cellular secretion, while chitosan-coated nanoparticles escape from endosomes and enter the cytosol. Encapsulation within the porous silicon matrix protects these nanoparticle surface-tailored properties, and enhances endosomal escape of chitosan-coated nanoparticles. Thus, LEVs provide a mechanism for shielded transport of nanoparticles to the lesion, cellular manipulation at multiple levels, and a means for targeting both within and between cells.


Asunto(s)
Portadores de Fármacos/metabolismo , Endosomas/metabolismo , Nanopartículas , Animales , Transporte Biológico , Línea Celular , Portadores de Fármacos/química , Exocitosis/fisiología , Macrófagos/metabolismo , Ratones
13.
Nanoscale ; 2(8): 1512-20, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20820744

RESUMEN

Mesoporous silicon particles show great promise for use in drug delivery and imaging applications as carriers for second-stage nanoparticles and higher order particles or therapeutics. Modulation of particle geometry, surface chemistry, and porosity allows silicon particles to be optimized for specific applications such as vascular targeting and avoidance of biological barriers commonly found between the site of drug injection and the final destination. In this study, the intracellular trafficking of unloaded carrier silicon particles and carrier particles loaded with secondary iron oxide nanoparticles was investigated. Following cellular uptake, membrane-encapsulated silicon particles migrated to the perinuclear region of the cell by a microtubule-driven mechanism. Surface charge, shape (spherical and hemispherical) and size (1.6 and 3.2 microm) of the particle did not alter the rate of migration. Maturation of the phagosome was associated with an increase in acidity and acquisition of markers of late endosomes and lysosomes. Cellular uptake of iron oxide nanoparticle-loaded silicon particles resulted in sorting of the particles and trafficking to unique destinations. The silicon carriers remained localized in phagosomes, while the second stage iron oxide nanoparticles were sorted into multi-vesicular bodies that dissociated from the phagosome into novel membrane-bound compartments. Release of iron from the cells may represent exocytosis of iron oxide nanoparticle-loaded vesicles. These results reinforce the concept of multi-functional nanocarriers, in which different particles are able to perform specific tasks, in order to deliver single- or multi-component payloads to specific sub-cellular compartments.


Asunto(s)
Nanopartículas del Metal/administración & dosificación , Silicio/administración & dosificación , Membrana Celular/metabolismo , Portadores de Fármacos/química , Células Endoteliales/metabolismo , Endotelio Vascular/citología , Compuestos Férricos/química , Humanos , Nanopartículas del Metal/química , Microscopía Electrónica de Transmisión , Microtúbulos/metabolismo , Fagosomas/metabolismo , Porosidad , Silicio/química , Espectroscopía Infrarroja por Transformada de Fourier
14.
Small ; 6(12): 1329-40, 2010 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-20517877

RESUMEN

The realization that blood-borne delivery systems must overcome a multiplicity of biological barriers has led to the fabrication of a multistage delivery system (MDS) designed to temporally release successive stages of particles or agents to conquer sequential barriers, with the goal of enhancing delivery of therapeutic and diagnostic agents to the target site. In its simplest form, the MDS comprises stage-one porous silicon microparticles that function as carriers of second-stage nanoparticles. Cellular uptake of nontargeted discoidal silicon microparticles by macrophages is confirmed by electron and atomic force microscopy (AFM). Using superparamagnetic iron oxide nanoparticles (SPIONs) as a model of secondary nanoparticles, successful loading of the porous matrix of silicon microparticles is achieved, and retention of the nanoparticles is enhanced by aminosilylation of the loaded microparticles with 3-aminopropyltriethoxysilane. The impact of silane concentration and reaction time on the nature of the silane polymer on porous silicon is investigated by AFM and X-ray photoelectron microscopy. Tissue samples from mice intravenously administered the MDS support co-localization of silicon microparticles and SPIONs across various tissues with enhanced SPION release in spleen, compared to liver and lungs, and enhanced retention of SPIONs following silane capping of the MDS. Phantom models of the SPION-loaded MDS display negative contrast in magnetic resonance images. In addition to forming a cap over the silicon pores, the silane polymer provides free amines for antibody conjugation to the microparticles, with both VEGFR-2- and PECAM-specific antibodies leading to enhanced endothelial association. This study demonstrates the assembly and cellular association of a multiparticle delivery system that is biomolecularly targeted and has potential for applications in biological imaging.


Asunto(s)
Sistemas de Liberación de Medicamentos , Nanopartículas/química , Animales , Línea Celular , Ratones , Microscopía de Fuerza Atómica , Nanotecnología , Espectroscopía de Fotoelectrones , Porosidad
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