Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
1.
ACS Nano ; 15(4): 6684-6698, 2021 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-33769805

RESUMEN

Ideal controlled pulmonary drug delivery systems provide sustained release by retarding lung clearance mechanisms and efficient lung deposition to maintain therapeutic concentrations over prolonged time. Here, we use atomic layer deposition (ALD) to simultaneously tailor the release and aerosolization properties of inhaled drug particles without the need for lactose carrier. In particular, we deposit uniform nanoscale oxide ceramic films, such as Al2O3, TiO2, and SiO2, on micronized budesonide particles, a common active pharmaceutical ingredient for the treatment of respiratory diseases. In vitro dissolution and ex vivo isolated perfused rat lung tests demonstrate dramatically slowed release with increasing nanofilm thickness, regardless of the nature of the material. Ex situ transmission electron microscopy at various stages during dissolution unravels mostly intact nanofilms, suggesting that the release mechanism mainly involves the transport of dissolution media through the ALD films. Furthermore, in vitro aerosolization testing by fast screening impactor shows a ∼2-fold increase in fine particle fraction (FPF) for each ALD-coated budesonide formulation after 10 ALD process cycles, also applying very low patient inspiratory pressures. The higher FPFs after the ALD process are attributed to the reduction in the interparticle force arising from the ceramic surfaces, as evidenced by atomic force microscopy measurements. Finally, cell viability, cytokine release, and tissue morphology analyses verify a safe and efficacious use of ALD-coated budesonide particles at the cellular level. Therefore, surface nanoengineering by ALD is highly promising in providing the next generation of inhaled formulations with tailored characteristics of drug release and lung deposition, thereby enhancing controlled pulmonary delivery opportunities.


Asunto(s)
Budesonida , Dióxido de Silicio , Administración por Inhalación , Aerosoles , Humanos , Lactosa , Pulmón , Tamaño de la Partícula , Polvos
2.
Front Immunol ; 11: 1991, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32903476

RESUMEN

Evidence from the global outbreak of SARS-CoV-2 has clearly demonstrated that individuals with pre-existing comorbidities are at a much greater risk of dying from COVID-19. This is of great concern for individuals living with these conditions, and a major challenge for global healthcare systems and biomedical research. Not all comorbidities confer the same risk, however, many affect the function of the immune system, which in turn directly impacts the response to COVID-19. Furthermore, the myriad of drugs prescribed for these comorbidities can also influence the progression of COVID-19 and limit additional treatment options available for COVID-19. Here, we review immune dysfunction in response to SARS-CoV-2 infection and the impact of pre-existing comorbidities on the development of COVID-19. We explore how underlying disease etiologies and common therapies used to treat these conditions exacerbate COVID-19 progression. Moreover, we discuss the long-term challenges associated with the use of both novel and repurposed therapies for the treatment of COVID-19 in patients with pre-existing comorbidities.


Asunto(s)
Comorbilidad , Infecciones por Coronavirus/tratamiento farmacológico , Infecciones por Coronavirus/mortalidad , Neumonía Viral/tratamiento farmacológico , Neumonía Viral/mortalidad , Betacoronavirus/efectos de los fármacos , COVID-19 , Infecciones por Coronavirus/patología , Humanos , Pandemias , Neumonía Viral/patología , Riesgo , Factores de Riesgo , SARS-CoV-2
3.
Mol Ther ; 27(11): 1950-1962, 2019 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-31427168

RESUMEN

Lipid nanoparticles have great potential for delivering nucleic-acid-based therapeutics, but low efficiency limits their broad clinical translation. Differences in transfection capacity between in vitro models used for nanoparticle pre-clinical testing are poorly understood. To address this, using a clinically relevant lipid nanoparticle (LNP) delivering mRNA, we highlight specific endosomal characteristics in in vitro tumor models that impact protein expression. A 30-cell line LNP-mRNA transfection screen identified three cell lines having low, medium, and high transfection that correlated with protein expression when they were analyzed in tumor models. Endocytic profiling of these cell lines identified major differences in endolysosomal morphology, localization, endocytic uptake, trafficking, recycling, and endolysosomal pH, identified using a novel pH probe. High-transfecting cells showed rapid LNP uptake and trafficking through an organized endocytic pathway to lysosomes or rapid exocytosis. Low-transfecting cells demonstrated slower endosomal LNP trafficking to lysosomes and defective endocytic organization and acidification. Our data establish that efficient LNP-mRNA transfection relies on an early and narrow endosomal escape window prior to lysosomal sequestration and/or exocytosis. Endocytic profiling should form an important pre-clinical evaluation step for nucleic acid delivery systems to inform model selection and guide delivery-system design for improved clinical translation.


Asunto(s)
Expresión Génica , Lípidos/química , Nanopartículas , ARN Mensajero/genética , Transfección , Línea Celular Tumoral , Endocitosis , Endosomas/metabolismo , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Genes Reporteros , Humanos , Concentración de Iones de Hidrógeno , Lisosomas/metabolismo , Nanopartículas/química , ARN Mensajero/administración & dosificación , Transfección/métodos
4.
Nanoscale ; 11(14): 6990-7001, 2019 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-30916672

RESUMEN

Extracellular vesicles (EVs) mediate cellular communication through the transfer of active biomolecules, raising interest in using them as biological delivery vehicles for therapeutic drugs. For drug delivery applications, it is important to understand the intrinsic safety and toxicity liabilities of EVs. Nanoparticles, including EVs, typically demonstrate significant accumulation in the liver after systemic administration in vivo. We confirmed uptake of EVs derived from Expi293F cells into HepG2 cells and did not detect any signs of hepatotoxicity measured by cell viability, functional secretion of albumin, plasma membrane integrity, and mitochondrial and lysosomal activity even at high exposures of up to 5 × 1010 EVs per mL. Whole genome transcriptome analysis was used to measure potential effects on the gene expression in the recipient HepG2 cells at 24 h following exposure to EVs. Only 0.6% of all genes were found to be differentially expressed displaying less than 2-fold expression change, with genes related to inflammation or toxicity being unaffected. EVs did not trigger any proinflammatory cytokine response in HepG2 cells. However, minor changes were noted in human blood for interleukin (IL)-8, IL-6, and monocyte chemotactic protein 1 (MCP-1). Administration of 5 × 1010 Expi293F-derived EVs to BALB/c mice did not result in any histopathological changes or increases of liver transaminases or cytokine levels, apart from a modest increase in keratinocyte chemoattractant (KC). The absence of any significant toxicity associated with EVs in vitro and in vivo supports the prospective use of EVs for therapeutic applications and for drug delivery.


Asunto(s)
Vesículas Extracelulares/fisiología , Hígado/patología , Animales , Citocinas/metabolismo , Vesículas Extracelulares/trasplante , Células HEK293 , Células Hep G2 , Humanos , Mediadores de Inflamación/metabolismo , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Nanopartículas/química , Albúmina Sérica/metabolismo , Transaminasas/metabolismo , Transcriptoma
6.
Toxicol Sci ; 158(1): 213-226, 2017 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-28453775

RESUMEN

Many drugs designed to inhibit kinases have their clinical utility limited by cardiotoxicity-related label warnings or prescribing restrictions. While this liability is widely recognized, designing safer kinase inhibitors (KI) requires knowledge of the causative kinase(s). Efforts to unravel the kinases have encountered pharmacology with nearly prohibitive complexity. At therapeutically relevant concentrations, KIs show promiscuity distributed across the kinome. Here, to overcome this complexity, 65 KIs with known kinome-scale polypharmacology profiles were assessed for effects on cardiomyocyte (CM) beating. Changes in human iPSC-CM beat rate and amplitude were measured using label-free cellular impedance. Correlations between beat effects and kinase inhibition profiles were mined by computation analysis (Matthews Correlation Coefficient) to identify associated kinases. Thirty kinases met criteria of having (1) pharmacological inhibition correlated with CM beat changes, (2) expression in both human-induced pluripotent stem cell-derived cardiomyocytes and adult heart tissue, and (3) effects on CM beating following single gene knockdown. A subset of these 30 kinases were selected for mechanistic follow up. Examples of kinases regulating processes spanning the excitation-contraction cascade were identified, including calcium flux (RPS6KA3, IKBKE) and action potential duration (MAP4K2). Finally, a simple model was created to predict functional cardiotoxicity whereby inactivity at three sentinel kinases (RPS6KB1, FAK, STK35) showed exceptional accuracy in vitro and translated to clinical KI safety data. For drug discovery, identifying causative kinases and introducing a predictive model should transform the ability to design safer KI medicines. For cardiovascular biology, discovering kinases previously unrecognized as influencing cardiovascular biology should stimulate investigation of underappreciated signaling pathways.


Asunto(s)
Corazón/efectos de los fármacos , Inhibidores de Proteínas Quinasas/toxicidad , Calcio/metabolismo , Humanos , Células Madre Pluripotentes Inducidas/efectos de los fármacos , Células Madre Pluripotentes Inducidas/enzimología , Miocitos Cardíacos/citología , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/enzimología , Miocitos Cardíacos/metabolismo , Proteínas Quinasas/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
7.
ACS Med Chem Lett ; 8(2): 239-244, 2017 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-28197319

RESUMEN

Mcl-1 is a pro-apoptotic BH3 protein family member similar to Bcl-2 and Bcl-xL. Overexpression of Mcl-1 is often seen in various tumors and allows cancer cells to evade apoptosis. Here we report the discovery and optimization of a series of non-natural peptide Mcl-1 inhibitors. Screening of DNA-encoded libraries resulted in hit compound 1, a 1.5 µM Mcl-1 inhibitor. A subsequent crystal structure demonstrated that compound 1 bound to Mcl-1 in a ß-turn conformation, such that the two ends of the peptide were close together. This proximity allowed for the linking of the two ends of the peptide to form a macrocycle. Macrocyclization resulted in an approximately 10-fold improvement in binding potency. Further exploration of a key hydrophobic interaction with Mcl-1 protein and also with the moiety that engages Arg256 led to additional potency improvements. The use of protein-ligand crystal structures and binding kinetics contributed to the design and understanding of the potency gains. Optimized compound 26 is a <3 nM Mcl-1 inhibitor, while inhibiting Bcl-2 at only 5 µM and Bcl-xL at >99 µM, and induces cleaved caspase-3 in MV4-11 cells with an IC50 of 3 µM after 6 h.

8.
Can J Occup Ther ; 83(4): 216-225, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27301479

RESUMEN

BACKGROUND: The Cognitive Orientation to daily Occupational Performance (CO-OP) approach-now trademarked as the CO-OPApproach-was introduced in the literature in 2001 as an intervention to improve real-world performance in children with developmental coordination disorder. CO-OP has since appeared in numerous publications and has seen adoption with various populations. No compilation of the CO-OP literature is available. PURPOSE: The purpose of this scoping review was to examine the extent (number) and nature (features and characteristics) of the literature on CO-OP. METHOD: Using the scoping review methodology outlined by Arksey and O'Malley, 10 online databases were searched for materials discussing CO-OP. Materials found were reviewed by two reviewers, independently. Articles were categorized according to identified study characteristics. FINDINGS: In all, 94 documents were found, including 27 research articles examining application and adaptations of CO-OP with eight populations. In all cases, the approach was deemed useful; however, in many cases, adaptations to the CO-OP protocol were recommended. IMPLICATIONS: CO-OP has been applied with a number of populations. There is now sufficient research to warrant a systematic review of the research literature.


Asunto(s)
Cognición , Trastornos de la Destreza Motora/rehabilitación , Terapia Ocupacional , Práctica Clínica Basada en la Evidencia , Humanos , Trastornos de la Destreza Motora/psicología , Atención Dirigida al Paciente
9.
Clin Appl Thromb Hemost ; 21(1): 41-7, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24842886

RESUMEN

To assess the impact of preanalytical variables of time and temperature on prothrombin time (PT), activated partial thromboplastin time (aPTT), dilute Russell viper venom time (DRVVT), activated protein C resistance (APCR), and d-dimer, samples from 23 healthy individuals and 18 patients having coagulopathy with known abnormal PT and aPTT were collected. Plasma from each individual was separately pooled and aliquoted; the first 2 aliquots were stored at room temperature then analyzed at 2 hours (baseline) and 4 hours postcollection. The remaining aliquots were stored at -20°C and thawed for analysis at 48 hours, 1, and 2 weeks. In both healthy participants and participants with coagulopathy, PT, aPTT, APCR, DRVVT, and D-dimer had no significant changes at 4 and 48 hours, and 1 and 2 weeks postcollection compared to baseline, or the changes were less than 10%. The results indicate PT, aPTT, DRVVT, APCR, and d-dimer can be stored for 2 weeks at -20°C without compromising clinical interpretation in both healthy individuals and individuals with coagulopathy. Increasing storage time will facilitate sample processing from off-site clinics.


Asunto(s)
Resistencia a la Proteína C Activada/sangre , Análisis Químico de la Sangre/métodos , Pruebas de Coagulación Sanguínea , Recolección de Muestras de Sangre/métodos , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Resistencia a la Proteína C Activada/diagnóstico , Trastornos de la Coagulación Sanguínea/sangre , Trastornos de la Coagulación Sanguínea/diagnóstico , Estudios de Casos y Controles , Congelación , Humanos , Tiempo de Tromboplastina Parcial , Tiempo de Protrombina , Valores de Referencia , Temperatura , Factores de Tiempo
11.
J Appl Behav Anal ; 43(2): 279-83, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21119901

RESUMEN

We assessed preference for video or in vivo modeling using a concurrent-chains arrangement with 3 children with autism. The two modeling conditions produced similar acquisition rates and no differential selection (i.e., preference) for all 3 participants.


Asunto(s)
Trastorno Autístico/psicología , Prioridad del Paciente/psicología , Enseñanza/métodos , Grabación en Video/métodos , Niño , Condicionamiento Operante , Humanos , Masculino , Esquema de Refuerzo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...