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1.
Pharm Res ; 41(4): 751-763, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38443633

RESUMEN

PURPOSE: To evaluate the clinical feasibility and tolerability of large volume subcutaneous delivery at different injection depths for lean and non-lean subjects. METHODS: A single-center, randomized, subject-blinded, crossover study in 62 healthy subjects was conducted to evaluate delivery of a 10-cP solution containing hyaluronic acid. Subjects were separated into lean and non-lean cohort by SC thickness. A syringe pump was used to study the effect of different volumes (5, 12, 25 mL) of a viscous placebo solution and needle lengths (6, 9 and 12 mm) delivered at 0.5 mL/min. RESULTS: Across all treatments, injection sites were observed to have negligible leakage, ~34 kPa of back pressure, and VAS of mild pain with higher pain from needle insertion than during injection. While mild to moderate erythema was the most frequently reported ISR and edema was most prominent for 25 mL injections, all ISRs were resolved within 4 hours post injection. Subjects were unbothered by ISRs across all treatments and rated them as low distress scores (average 1.0-1.5 out of 6). CONCLUSION: SC injection of 25 mL is feasible and tolerable using a low-pain formulation for abdomen injection irrespective of subcutaneous thickness and injection depths at a delivery rate of 0.5 mL/min.


Asunto(s)
Dolor , Tejido Subcutáneo , Humanos , Inyecciones Subcutáneas , Estudios Cruzados , Dolor/tratamiento farmacológico
2.
Small ; 15(28): e1901233, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31131998

RESUMEN

Fluorescence imaging is a powerful tool for studying biologically relevant macromolecules, but its applicability is often limited by the fluorescent probe, which must demonstrate both high site-specificity and emission efficiency. In this regard, M13 virus, a versatile biological scaffold, has previously been used to both assemble fluorophores on its viral capsid with molecular precision and to also target a variety of cells. Although M13-fluorophore systems are highly selective, these complexes typically suffer from poor molecular detection limits due to low absorption cross-sections and moderate quantum yields. To overcome these challenges, a coassembly of the M13 virus, cyanine 3 dye, and silver nanoparticles is developed to create a fluorescent tag capable of binding with molecular precision with high emissivity. Enhanced emission of cyanine 3 of up to 24-fold is achieved by varying nanoparticle size and particle-fluorophore separation. In addition, it is found that the fluorescence enhancement increases with increasing dye surface density on the viral capsid. Finally, this highly fluorescent probe is applied for in vitro staining of E. coli. These results demonstrate an inexpensive framework for achieving tuned fluorescence enhancements. The methodology developed in this work is potentially amendable to fluorescent detection of a wide range of M13/cell combinations.


Asunto(s)
Bacteriófago M13/metabolismo , Carbocianinas/química , Fluorescencia , Nanopartículas del Metal/ultraestructura , Tamaño de la Partícula , Polietilenglicoles/química , Plata/química
3.
Proc Natl Acad Sci U S A ; 113(19): 5179-84, 2016 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-27114520

RESUMEN

Fluorescence imaging in the second near-infrared window (NIR-II, 1,000-1,700 nm) features deep tissue penetration, reduced tissue scattering, and diminishing tissue autofluorescence. Here, NIR-II fluorescent probes, including down-conversion nanoparticles, quantum dots, single-walled carbon nanotubes, and organic dyes, are constructed into biocompatible nanoparticles using the layer-by-layer (LbL) platform due to its modular and versatile nature. The LbL platform has previously been demonstrated to enable incorporation of diagnostic agents, drugs, and nucleic acids such as siRNA while providing enhanced blood plasma half-life and tumor targeting. This work carries out head-to-head comparisons of currently available NIR-II probes with identical LbL coatings with regard to their biodistribution, pharmacokinetics, and toxicities. Overall, rare-earth-based down-conversion nanoparticles demonstrate optimal biological and optical performance and are evaluated as a diagnostic probe for high-grade serous ovarian cancer, typically diagnosed at late stage. Successful detection of orthotopic ovarian tumors is achieved by in vivo NIR-II imaging and confirmed by ex vivo microscopic imaging. Collectively, these results indicate that LbL-based NIR-II probes can serve as a promising theranostic platform to effectively and noninvasively monitor the progression and treatment of serous ovarian cancer.


Asunto(s)
Colorantes Fluorescentes/síntesis química , Microscopía Fluorescente/métodos , Nanocápsulas/química , Neoplasias Ováricas/diagnóstico por imagen , Espectroscopía Infrarroja Corta/métodos , Animales , Línea Celular Tumoral , Medios de Contraste/síntesis química , Medios de Contraste/farmacocinética , Cristalización/métodos , Femenino , Colorantes Fluorescentes/farmacocinética , Humanos , Ratones , Ratones Endogámicos BALB C , Nanocápsulas/ultraestructura , Especificidad de Órganos , Neoplasias Ováricas/patología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Nanomedicina Teranóstica/métodos , Distribución Tisular
4.
Nano Lett ; 13(2): 637-42, 2013 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-23339821

RESUMEN

In photovoltaic devices, light harvesting (LH) and carrier collection have opposite relations with the thickness of the photoactive layer, which imposes a fundamental compromise for the power conversion efficiency (PCE). Unbalanced LH at different wavelengths further reduces the achievable PCE. Here, we report a novel approach to broadband balanced LH and panchromatic solar energy conversion using multiple-core-shell structured oxide-metal-oxide plasmonic nanoparticles. These nanoparticles feature tunable localized surface plasmon resonance frequencies and the required thermal stability during device fabrication. By simply blending the plasmonic nanoparticles with available photoactive materials, the broadband LH of practical photovoltaic devices can be significantly enhanced. We demonstrate a panchromatic dye-sensitized solar cell with an increased PCE from 8.3% to 10.8%, mainly through plasmon-enhanced photoabsorption in the otherwise less harvested region of solar spectrum. This general and simple strategy also highlights easy fabrication, and may benefit solar cells using other photoabsorbers or other types of solar-harvesting devices.

5.
iScience ; 27(2): 108626, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38318391

RESUMEN

Recent advancements in digital biomarkers have highlighted the importance of accelerometer and gyroscope data for monitoring activities, identifying motion-related diseases, and assessing disease severity. Prior studies predominantly limit sensor placement to one or two locations. Here, we conducted a trial focusing on the impact of sensor placement in predicting 21 common activities using convolutional neural networks (CNN) and long short-term memory networks (LSTM). Our research found that the optimal locations for activity detection are the right and left upper arms, right wrist, and lower back. These locations yielded an average AUC of 0.76-0.77 using both accelerometer and gyroscope data. Combining data from all locations improved AUC to 0.796 for accelerometer and 0.811 for gyroscope data. We also noted specific activity-body part sensitivity relationships. This study provides a valuable reference for selecting appropriate sensor locations in future digital biomarker studies focused on specific activities.

6.
Digit Biomark ; 7(1): 54-62, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37404864

RESUMEN

Introduction: PRESENCE was a phase 2 clinical trial assessing the efficacy of mevidalen, a D1 receptor positive allosteric modulator, for symptomatic treatment of Lewy body dementia (LBD). Mevidalen demonstrated improvements in motor and non-motor features of LBD, global functioning, and actigraphy-measured activity and daytime sleep. Adverse events (AEs) of fall were numerically increased in mevidalen-treated participants. Methods: A subset of PRESENCE participants wore a wrist actigraphy device for 2-week periods pre-, during, and posttreatment. Actigraphy sleep and activity measures were derived per period and analyzed to assess for their association with participants' reports of an AE of fall. Prespecified baseline and treatment-emergent clinical characteristics were also included in the retrospective analysis of falls. Independent-samples t test and χ2 test were performed to compare the means and proportions between individuals with/without falls. Results: A trend toward more falls was observed with mevidalen treatment (31/258 mevidalen-treated vs. 4/86 in placebo-treated participants: p = 0.12). Higher body mass index (BMI) (p < 0.05), more severe disease measured by baseline Movement Disorder Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) part II (p < 0.05), and a trend toward improved Alzheimer's Disease Assessment Scale-Cognitive Subscale 13 (ADAS-Cog13) (p = 0.06) were associated with individuals with falls. No statistically significant associations with falls and treatment-emergent changes were observed. Conclusion: The association of falls with worse baseline disease severity and higher BMI and overall trend toward improvements on cognitive and motor scales suggest that falls in PRESENCE may be related to increased activity in mevidalen-treated participants at greater risk for falling. Future studies to confirm this hypothesis using fall diaries and digital assessments are necessary.

7.
Small ; 8(7): 1006-11, 2012 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-22337601

RESUMEN

Utilization of the material-specific peptide-substrate interactions of M13 virus broadens colloidal stability window of graphene. The homogeneous distribution of graphene is maintained in weak acids and increased ionic strengths by complexing with virus. This graphene/virus conducting template is utilized in the synthesis of energy-storage materials to increase the conductivity of the composite electrode. Successful formation of the hybrid biological template is demonstrated by the mineralization of bismuth oxyfluoride as a cathode material for lithium-ion batteries, with increased loading and improved electronic conductivity.


Asunto(s)
Bacteriófago M13/química , Suministros de Energía Eléctrica , Grafito/química , Nanoestructuras/química , Bacteriófago M13/genética , Ingeniería Genética , Litio/química , Microscopía Electrónica de Transmisión , Nanoestructuras/ultraestructura
8.
J Parkinsons Dis ; 12(6): 1991-2004, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35694933

RESUMEN

BACKGROUND: PRESENCE was a Phase 2 trial assessing mevidalen for symptomatic treatment of Lewy body dementia (LBD). Participants received daily doses (10, 30, or 75 mg) of mevidalen (LY3154207) or placebo for 12 weeks. OBJECTIVE: To evaluate if frequent cognitive and motor tests using an iPad app and wrist-worn actigraphy to track activity and sleep could detect mevidalen treatment effects in LBD. METHODS: Of 340 participants enrolled in PRESENCE, 238 wore actigraphy for three 2-week periods: pre-, during, and post-intervention. A subset of participants (n = 160) enrolled in a sub-study using an iPad trial app with 3 tests: digital symbol substitution (DSST), spatial working memory (SWM), and finger-tapping. Compliance was defined as daily test completion or watch-wearing ≥23 h/day. Change from baseline to week 12 (app) or week 8 (actigraphy) was used to assess treatment effects using Mixed Model Repeated Measures analysis. Pearson correlations between sensor-derived features and clinical endpoints were assessed. RESULTS: Actigraphy and trial app compliance was > 90% and > 60%, respectively. At baseline, daytime sleep positively correlated with Epworth Sleepiness Scale score (p < 0.01). Physical activity correlated with improvement on Movement Disorder Society -Unified Parkinson Disease Rating Scale (MDS-UPDRS) part II (p < 0.001). Better scores of DSST and SWM correlated with lower Alzheimer Disease Assessment Scale -Cognitive 13-Item Scale (ADAS-Cog13) (p < 0.001). Mevidalen treatment (30 mg) improved SWM (p < 0.01), while dose-dependent decreases in daytime sleep (10 mg: p < 0.01, 30 mg: p < 0.05, 75 mg: p < 0.001), and an increase in walking minutes (75 mg dose: p < 0.001) were observed, returning to baseline post-intervention. CONCLUSION: Devices used in the LBD population achieved adequate compliance and digital metrics detected statistically significant treatment effects.


Asunto(s)
Enfermedad por Cuerpos de Lewy , Fármacos Neuroprotectores , Enfermedad de Parkinson , Enfermedad de Alzheimer , Biomarcadores , Cognición , Humanos , Enfermedad por Cuerpos de Lewy/tratamiento farmacológico , Fármacos Neuroprotectores/farmacología
9.
Sci Rep ; 9(1): 3873, 2019 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-30846704

RESUMEN

Detection of biological features at the cellular level with sufficient sensitivity in complex tissue remains a major challenge. To appreciate this challenge, this would require finding tens to hundreds of cells (a 0.1 mm tumor has ~125 cells), out of ~37 trillion cells in the human body. Near-infrared optical imaging holds promise for high-resolution, deep-tissue imaging, but is limited by autofluorescence and scattering. To date, the maximum reported depth using second-window near-infrared (NIR-II: 1000-1700 nm) fluorophores is 3.2 cm through tissue. Here, we design an NIR-II imaging system, "Detection of Optically Luminescent Probes using Hyperspectral and diffuse Imaging in Near-infrared" (DOLPHIN), that resolves these challenges. DOLPHIN achieves the following: (i) resolution of probes through up to 8 cm of tissue phantom; (ii) identification of spectral and scattering signatures of tissues without a priori knowledge of background or autofluorescence; and (iii) 3D reconstruction of live whole animals. Notably, we demonstrate noninvasive real-time tracking of a 0.1 mm-sized fluorophore through the gastrointestinal tract of a living mouse, which is beyond the detection limit of current imaging modalities.


Asunto(s)
Imagen Óptica/instrumentación , Imagen Óptica/métodos , Tejido Adiposo/diagnóstico por imagen , Algoritmos , Animales , Encéfalo/diagnóstico por imagen , Mama/diagnóstico por imagen , Bovinos , Diseño de Equipo , Colorantes Fluorescentes , Tracto Gastrointestinal/diagnóstico por imagen , Humanos , Imagenología Tridimensional/instrumentación , Imagenología Tridimensional/métodos , Ratones Desnudos , Músculos/diagnóstico por imagen , Fantasmas de Imagen , Piel/diagnóstico por imagen
10.
Biomaterials ; 134: 202-215, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28482280

RESUMEN

Cell-intrinsic reporters such as luciferase (LUC) and red fluorescent protein (RFP) have been commonly utilized in preclinical studies to image tumor growth and to monitor therapeutic responses. While extrinsic reporters that emit near infrared I (NIR-I: 650-950 nm) or near-infrared II (NIR-II: 1000-1700 nm) optical signals have enabled minimization of tissue autofluorescence and light scattering, it has remained unclear as to whether their use has afforded more accurate tumor imaging in small animals. Here, we developed a novel optical imaging construct comprised of rare earth lanthanide nanoparticles coated with biodegradable diblock copolymers and doped with organic fluorophores, generating NIR-I and NIR-II emissive bands upon optical excitation. Simultaneous injection of multiple spectrally-unique nanoparticles into mice bearing tumor implants established via intraperitoneal dissemination of LUC+/RFP+ OVCAR-8 ovarian cancer cells enabled direct comparisons of imaging with extrinsic vs. intrinsic reporters, NIR-II vs. NIR-I signals, as well as targeted vs. untargeted exogenous contrast agents in the same animal and over time. We discovered that in vivo optical imaging at NIR-II wavelengths facilitates more accurate detection of smaller and earlier tumor deposits, offering enhanced sensitivity, improved spatial contrast, and increased depths of tissue penetration as compared to imaging with visible or NIR-I fluorescent agents. Our work further highlights the hitherto underappreciated enhancements in tumor accumulation that may be achieved with intraperitoneal as opposed to intravenous administration of nanoparticles. Lastly, we found discrepancies in the fidelity of tumor uptake that could be obtained by utilizing small molecules for in vivo as opposed to in vitro targeting of nanoparticles to disseminated tumors.


Asunto(s)
Neoplasias Ováricas/diagnóstico por imagen , Neoplasias Ováricas/diagnóstico , Espectroscopía Infrarroja Corta/métodos , Animales , Línea Celular Tumoral , Detección Precoz del Cáncer/métodos , Femenino , Humanos , Ratones , Ratones Desnudos , Nanopartículas/química , Ensayos Antitumor por Modelo de Xenoinjerto
11.
ACS Nano ; 7(8): 6563-74, 2013 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-23808626

RESUMEN

By genetically encoding affinity for inorganic materials into the capsid proteins of the M13 bacteriophage, the virus can act as a template for the synthesis of nanomaterial composites for use in various device applications. Herein, the M13 bacteriophage is employed to build a multifunctional and three-dimensional scaffold capable of improving both electron collection and light harvesting in dye-sensitized solar cells (DSSCs). This has been accomplished by binding gold nanoparticles (AuNPs) to the virus proteins and encapsulating the AuNP-virus complexes in TiO2 to produce a plasmon-enhanced and nanowire (NW)-based photoanode. The NW morphology exhibits an improved electron diffusion length compared to traditional nanoparticle-based DSSCs, and the AuNPs increase the light absorption of the dye-molecules through the phenomenon of localized surface plasmon resonance. Consequently, we report a virus-templated and plasmon-enhanced DSSC with an efficiency of 8.46%, which is achieved through optimizing both the NW morphology and the concentration of AuNPs loaded into the solar cells. In addition, we propose a theoretical model that predicts the experimentally observed trends of plasmon enhancement.


Asunto(s)
Bacteriófago M13/química , Energía Solar , Cápside/química , Colorantes/química , Electrodos , Transporte de Electrón , Electrones , Luz , Nanopartículas del Metal/química , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Nanocables/química , Luz Solar , Resonancia por Plasmón de Superficie , Titanio/química , Virus/química , Difracción de Rayos X
12.
Adv Mater ; 24(21): 2885-9, 2012 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-22517374

RESUMEN

A synthetic method of using genetically engineered M13 virus to mineralize perovskite nanomaterials, particularly strontium titanate (STO) and bismuth ferrite (BFO), is presented. Genetically engineered viruses provide effective templates for perovskite nanomaterials. The virus-templated nanocrystals are small in size, highly crystalline, and show photocatalytic and photovoltaic properties.


Asunto(s)
Compuestos de Calcio/química , Nanoestructuras/química , Óxidos/química , Energía Solar , Titanio/química , Bacteriófago M13/genética , Bacteriófago M13/metabolismo , Proteínas de la Cápside/química , Proteínas de la Cápside/metabolismo , Catálisis , Colorantes/química , Cristalización , Luz , Estroncio/química
13.
ACS Nano ; 5(9): 7108-16, 2011 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-21815674

RESUMEN

We have investigated the effects of localized surface plasmons (LSPs) on the performance of dye-sensitized solar cells (DSSCs). The LSPs from Ag nanoparticles (NPs) increase the absorption of the dye molecules, allowing us to decrease the thickness of photoanodes, which improves electron collection and device performance. The plasmon-enhanced DSSCs became feasible through incorporating core-shell Ag@TiO(2) NPs into conventional TiO(2) photoanodes. The thin shell keeps the photoelectrons from recombining on the surface of metal NPs with dye and electrolyte and improves the stability of metal NPs. With 0.6 wt % Ag@TiO(2) NPs, the power conversion efficiency of DSSCs with thin photoanodes (1.5 µm) increases from 3.1% to 4.4%. Moreover, a small amount of Ag@TiO(2) NPs (0.1 wt %) improves efficiency from 7.8% to 9.0% while decreasing photoanode thickness by 25% for improved electron collection. In addition, plasmon-enhanced DSSCs require 62% less material to maintain the same efficiency as conventional DSSCs.

14.
Nat Nanotechnol ; 6(6): 377-84, 2011 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-21516089

RESUMEN

The performance of photovoltaic devices could be improved by using rationally designed nanocomposites with high electron mobility to efficiently collect photo-generated electrons. Single-walled carbon nanotubes exhibit very high electron mobility, but the incorporation of such nanotubes into nanocomposites to create efficient photovoltaic devices is challenging. Here, we report the synthesis of single-walled carbon nanotube-TiO(2) nanocrystal core-shell nanocomposites using a genetically engineered M13 virus as a template. By using the nanocomposites as photoanodes in dye-sensitized solar cells, we demonstrate that even small fractions of nanotubes improve the power conversion efficiency by increasing the electron collection efficiency. We also show that both the electronic type and degree of bundling of the nanotubes in the nanotube/TiO(2) complex are critical factors in determining device performance. With our approach, we achieve a power conversion efficiency in the dye-sensitized solar cells of 10.6%.


Asunto(s)
Nanocompuestos/química , Nanopartículas/química , Nanotubos de Carbono/química , Fármacos Fotosensibilizantes/química , Titanio/química , Conductividad Eléctrica , Suministros de Energía Eléctrica , Transporte de Electrón , Electrones , Diseño de Equipo , Ensayo de Materiales , Nanotecnología/instrumentación , Tamaño de la Partícula , Energía Solar , Propiedades de Superficie
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