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1.
Chronic Obstr Pulm Dis ; 11(1): 114-120, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-37828644

RESUMEN

The advancement of artificial intelligence (AI) capabilities has paved the way for a new frontier in medicine, which has the capability to reduce the burden of COPD globally. AI may reduce health care-associated expenses while potentially increasing diagnostic specificity, improving access to early COPD diagnosis, and monitoring COPD progression and subsequent disease management. We evaluated how AI can be integrated into COPD diagnosing globally and leveraged in resource-constrained settings.AI has been explored in diagnosing and phenotyping COPD through auscultation, pulmonary function testing, and imaging. Clinician collaboration with AI has increased the performance of COPD diagnosing and highlights the important role of clinical decision-making in AI integration. Likewise, AI analysis of computer tomography (CT) imaging in large population-based cohorts has increased diagnostic ability, severity classification, and prediction of outcomes related to COPD. Moreover, a multimodality approach with CT imaging, demographic data, and spirometry has been shown to improve machine learning predictions of the progression to COPD compared to each modality alone. Prior research has primarily been conducted in high-income country settings, which may lack generalization to a global population. AI is a World Health Organization priority with the potential to reduce health care barriers in low- and middle-income countries. We recommend a collaboration between clinicians and an AI-supported multimodal approach to COPD diagnosis as a step towards achieving this goal. We believe the interplay of CT imaging, spirometry, biomarkers, and sputum analysis may provide unique insights across settings that could provide a basis for clinical decision-making that includes early intervention for those diagnosed with COPD.

2.
Int J Hyperthermia ; 40(1): 2222941, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37344380

RESUMEN

BACKGROUND: Neuroblastoma (NB) is the most common extracranial solid tumor of childhood, and high-risk disease is resistant to intensive treatment. Histotripsy is a focused ultrasound therapy under development for tissue ablation via bubble activity. The goal of this study was to assess outcomes of histotripsy ablation in a xenograft model of high-risk NB. METHODS: Female NCr nude mice received NGP-luciferase cells intrarenally. Under ultrasound image guidance, histotripsy pulses were applied over a distance of 4-6 mm within the tumors. Bioluminescence indicative of tumor viability was quantified before, immediately after, and 24 h after histotripsy exposure. Tumors were immunostained to assess apoptosis (TUNEL), endothelium (endomucin), pericytes (αSMA), hypoxia (pimonidazole), vascular endothelial growth factor A (VEGFA), and platelet-derived growth factor-B (PDGF-B). The apoptotic cytokine TNFα and its downstream effector cleaved caspase-3 (c-casp-3) were assessed with SDS-PAGE. RESULTS: Histotripsy induced a 50% reduction in bioluminescence compared to untreated controls, with an absence of nuclei in the treatment core surrounded by a dense rim of TUNEL-positive cells. Tumor regions not targeted by histotripsy also showed an increase in TUNEL staining density. Increased apoptosis in histotripsy samples was consistent with increases in TNFα and c-casp-3 relative to controls. Treated tumors exhibited a decrease in hypoxia, VEGF, PDGF-B, and pericyte coverage of vasculature compared to control samples. Further, increases in vasodilation were found in histotripsy-treated specimens. CONCLUSIONS: In addition to ablative effects, histotripsy was found to drive tumor apoptosis through intrinsic pathways, altering blood vessel architecture, and reducing hypoxia.


Asunto(s)
Ultrasonido Enfocado de Alta Intensidad de Ablación , Neuroblastoma , Animales , Ratones , Humanos , Femenino , Factor A de Crecimiento Endotelial Vascular , Factor de Necrosis Tumoral alfa , Xenoinjertos , Ratones Desnudos , Neuroblastoma/terapia , Hipoxia , Apoptosis , Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos
3.
Ultrasound Med Biol ; 49(1): 90-105, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36241589

RESUMEN

Continuous-flow acoustofluidic technologies can potentially improve processing of T lymphocytes for cell therapies by addressing the limitations with viral and non-viral delivery methods. The objective of this study was to assess the intracellular delivery efficiency with acoustofluidic treatment compared with that of static ultrasound treatment. Optimization of parameters in acoustofluidic and static configurations was performed by assessing intracellular delivery of a fluorescent compound (calcein) in viable human Jurkat T lymphocytes. Ultrasound pressure and the concentration of cationic phospholipid-coated microbubbles influenced calcein delivery in both systems. In the static system, a treatment time of 45 s increased molecular delivery compared with 0-30 s (p < 0.01). Refined parameters were used to assess molecular delivery of small and large compounds (0.6-kDa calcein and 150-kDa fluorescein isothiocyanate-dextran, respectively) after ultrasound treatment with the acoustofluidic or static systems. Molecular delivery was similar with refined parameters for acoustofluidic treatment and static treatment (p > 0.05), even though acoustofluidic treatment had lower microbubble concentration (24 µg/mL vs. 94 µg/mL) and shorter treatment time (∼2-3 s vs. 45 s). This study indicates that the acoustofluidic system can significantly enhance intracellular molecular delivery, which could potentially enable acoustofluidic cell transfection during continuous flow processing for manufacture of cell therapies or other applications.


Asunto(s)
Microburbujas , Linfocitos T , Humanos , Transfección , Ultrasonografía , Sistemas de Liberación de Medicamentos/métodos
4.
J Vis Exp ; (167)2021 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-33554963

RESUMEN

Efficient intracellular delivery of biomolecules is required for a broad range of biomedical research and cell-based therapeutic applications. Ultrasound-mediated sonoporation is an emerging technique for rapid intracellular delivery of biomolecules. Sonoporation occurs when cavitation of gas-filled microbubbles forms transient pores in nearby cell membranes, which enables rapid uptake of biomolecules from the surrounding fluid. Current techniques for in vitro sonoporation of cells in suspension are limited by slow throughput, variability in the ultrasound exposure conditions for each cell, and high cost. To address these limitations, a low-cost acoustofluidic device has been developed which integrates an ultrasound transducer in a PDMS-based fluidic device to induce consistent sonoporation of cells as they flow through the channels in combination with ultrasound contrast agents. The device is fabricated using standard photolithography techniques to produce the PDMS-based fluidic chip. An ultrasound piezo disk transducer is attached to the device and driven by a microcontroller. The assembly can be integrated inside a 3D-printed case for added protection. Cells and microbubbles are pushed through the device using a syringe pump or a peristaltic pump connected to PVC tubing. Enhanced delivery of biomolecules to human T cells and lung cancer cells is demonstrated with this acoustofluidic system. Compared to bulk treatment approaches, this acoustofluidic system increases throughput and reduces variability, which can improve cell processing methods for biomedical research applications and manufacturing of cell-based therapeutics.


Asunto(s)
Acústica/instrumentación , Células/metabolismo , Fluoresceína/metabolismo , Trehalosa/metabolismo , Células A549 , Células Cultivadas , Medios de Contraste/química , Humanos , Microburbujas , Linfocitos T/citología , Ultrasonido
5.
J Acoust Soc Am ; 150(6): 4534, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34972278

RESUMEN

Cell-based therapies have garnered significant interest to treat cancer and other diseases. Acoustofluidic technologies are in development to improve cell therapy manufacturing by facilitating rapid molecular delivery across the plasma membrane via ultrasound and microbubbles (MBs). In this study, a three-dimensional (3D) printed acoustofluidic device was used to deliver a fluorescent molecule, calcein, to human T cells. Intracellular delivery of calcein was assessed after varying parameters such as MB face charge, MB concentration, flow channel geometry, ultrasound pressure, and delivery time point after ultrasound treatment. MBs with a cationic surface charge caused statistically significant increases in calcein delivery during acoustofluidic treatment compared to MBs with a neutral surface charge (p < 0.001). Calcein delivery was significantly higher with a concentric spiral channel geometry compared to a rectilinear channel geometry (p < 0.001). Additionally, calcein delivery was significantly enhanced at increased ultrasound pressures of 5.1 MPa compared to lower ultrasound pressures between 0-3.8 MPa (p < 0.001). These results demonstrate that a 3D-printed acoustofluidic device can significantly enhance intracellular delivery of biomolecules to T cells, which may be a viable approach to advance cell-based therapies.


Asunto(s)
Microburbujas , Linfocitos T , Sistemas de Liberación de Medicamentos , Humanos , Ultrasonografía
6.
PLoS One ; 15(5): e0233466, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32437399

RESUMEN

Systemic delivery of conventional chemotherapies can cause negative systemic toxicity, including reduced immunity and damage to organs such as the heart and kidneys-limiting the maximum dose that can be administered. Targeted therapies appear to address this problem by having a specific target while mitigating off-target effects. Biocompatible perfluorocarbon-based nanodroplet emulsions encapsulated by a phospholipid shell are in development for delivery of molecular compounds and hold promise as vehicles for targeted delivery of chemotherapeutics to tumors. When ultrasound is applied, perfluorocarbon will undergo a phase change-ultimately inducing transient perforation of the cell membrane when in close proximity, which is more commonly known as "sonoporation." Sonoporation allows enhanced intracellular delivery of molecular compounds and will reseal to encapsulate the molecular compound intracellularly. In this study, we investigated delivery of thymoquinone (TQ), a natural hydrophobic phytochemical compound with bioactivity in cancer cells. In addition, we conjugated a G-quadruplex aptamer, 'AS1411', to TQ-loaded nanodroplets and explored their effects on multiple human cancer cell lines. AS1411 binds nucleolin, which is over-expressed on the surface of cancer cells, and in addition to its tumor-targeting properties AS1411 has also been shown to induce anti-cancer effects. Thymoquinone was loaded onto AS1411-conjugated nanodroplet emulsion to assess activity against cancer cells. Confocal microscopy indicated uptake of AS1411-conjugated nanodroplets by cancer cells. Furthermore, AS1411-conjugated nanoemulsions loaded with TQ significantly enhanced cytotoxicity in cancer cells compared to free compound. These results demonstrate that AS1411 can be conjugated onto nanodroplet emulsions for targeted delivery to human cancer cells. This novel formulation offers significant potential for targeted delivery of hydrophobic chemotherapeutics to tumors for cancer treatment.


Asunto(s)
Benzoquinonas/administración & dosificación , Sistemas de Liberación de Medicamentos , Nanopartículas/administración & dosificación , Oligodesoxirribonucleótidos/administración & dosificación , Aptámeros de Nucleótidos , Línea Celular Tumoral , Humanos
7.
Biomicrofluidics ; 14(2): 024114, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32341725

RESUMEN

Preservation of erythrocytes in a desiccated state for storage at ambient temperature could simplify blood transfusions in austere environments, such as rural clinics, far-forward military operations, and during space travel. Currently, storage of erythrocytes is limited by a short shelf-life of 42 days at 4 °C, and long-term preservation requires a complex process that involves the addition and removal of glycerol from erythrocytes before and after storage at -80 °C, respectively. Natural compounds, such as trehalose, can protect cells in a desiccated state if they are present at sufficient levels inside the cell, but mammalian cell membranes lack transporters for this compound. To facilitate compound loading across the plasma membrane via ultrasound and microbubbles (sonoporation), a polydimethylsiloxane-based microfluidic device was developed. Delivery of fluorescein into erythrocytes was tested at various conditions to assess the effects of parameters such as ultrasound pressure, ultrasound pulse interval, microbubble dose, and flow rate. Changes in ultrasound pressure and mean flow rate caused statistically significant increases in fluorescein delivery of up to 73 ± 37% (p < 0.05) and 44 ± 33% (p < 0.01), respectively, compared to control groups, but no statistically significant differences were detected with changes in ultrasound pulse intervals. Following freeze-drying and rehydration, recovery of viable erythrocytes increased by up to 128 ± 32% after ultrasound-mediated loading of trehalose compared to control groups (p < 0.05). These results suggest that ultrasound-mediated molecular delivery in microfluidic channels may be a viable approach to process erythrocytes for long-term storage in a desiccated state at ambient temperatures.

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