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1.
Biomaterials ; 313: 122775, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39241549

RESUMEN

Acute Myocardial Infarction (AMI) has seen rising cases, particularly in younger people, leading to public health concerns. Standard treatments, like coronary artery recanalization, often don't fully repair the heart's microvasculature, risking heart failure. Advances show that Mesenchymal Stromal Cells (MSCs) transplantation improves cardiac function after AMI, but the harsh microenvironment post-AMI impacts cell survival and therapeutic results. MSCs aid heart repair via their membrane proteins and paracrine extracellular vesicles that carry microRNA-125b, which regulates multiple targets, preventing cardiomyocyte death, limiting fibroblast growth, and combating myocardial remodeling after AMI. This study introduces ultrasound-responsive phase-change bionic nanoparticles, leveraging MSCs' natural properties. These particles contain MSC membrane and microRNA-125b, with added macrophage membrane for stability. Using Ultrasound Targeted Microbubble Destruction (UTMD), this method targets the delivery of MSC membrane proteins and microRNA-125b to AMI's inflamed areas. This aims to enhance cardiac function recovery and provide precise, targeted AMI therapy.


Asunto(s)
Células Madre Mesenquimatosas , MicroARNs , Infarto del Miocardio , Nanopartículas , Infarto del Miocardio/terapia , Animales , Nanopartículas/química , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/citología , MicroARNs/metabolismo , MicroARNs/genética , Masculino , Recuperación de la Función , Trasplante de Células Madre Mesenquimatosas/métodos , Humanos , Materiales Biomiméticos/química , Materiales Biomiméticos/farmacología , Ratones , Microburbujas , Ondas Ultrasónicas
2.
Sci Rep ; 14(1): 20455, 2024 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-39227382

RESUMEN

Intratumoral injections have the potential for enhanced cancer treatment efficacy while reducing costs and systemic exposure. However, intratumoral drug injections can result in substantial off-target leakage and are invisible under standard imaging modalities like ultrasound (US) and x-ray. A thermosensitive poloxamer-based gel for drug delivery was developed that is visible using x-ray imaging (computed tomography (CT), cone beam CT, fluoroscopy), as well as using US by means of integrating perfluorobutane-filled microbubbles (MBs). MBs content was optimized using tissue mimicking phantoms and ex vivo bovine livers. Gel formulations less than 1% MBs provided gel depositions that were clearly identifiable on US and distinguishable from tissue background and with minimal acoustic artifacts. The cross-sectional areas of gel depositions obtained with US and CT imaging were similar in studies using ex vivo bovine liver and postmortem in situ swine liver. The gel formulation enhanced multimodal image-guided navigation, enabling fusion of ultrasound and x-ray/CT imaging, which may enhance targeting, definition of spatial delivery, and overlap of tumor and gel. Although speculative, such a paradigm for intratumoral drug delivery might streamline clinical workflows, reduce radiation exposure by reliance on US, and boost the precision and accuracy of drug delivery targeting during procedures. Imageable gels may also provide enhanced temporal and spatial control of intratumoral conformal drug delivery.


Asunto(s)
Sistemas de Liberación de Medicamentos , Hidrogeles , Hígado , Poloxámero , Ultrasonografía , Poloxámero/química , Animales , Hidrogeles/química , Hígado/diagnóstico por imagen , Hígado/metabolismo , Bovinos , Ultrasonografía/métodos , Sistemas de Liberación de Medicamentos/métodos , Microburbujas , Porcinos , Fantasmas de Imagen , Tomografía Computarizada por Rayos X/métodos , Tomografía Computarizada de Haz Cónico/métodos
3.
J Nanobiotechnology ; 22(1): 531, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39218878

RESUMEN

Ferroptosis, triggered by iron overload and excessive lipid peroxidation, plays a pivotal role in the progression of DOX-induced cardiomyopathy (DIC), and thus limits the use of doxorubicin (DOX) in clinic. Here, we further showed that cardiac ferroptosis induced by DOX in mice was attributed to up-regulation of Hmox1, as knockdown of Hmox1 effectively inhibited cardiomyocyte ferroptosis. To targeted delivery of siRNA into cardiomyocytes, siRNA-encapsulated exosomes were injected followed by ultrasound microbubble targeted destruction (UTMD) in the heart region. UTMD greatly facilitated exosome delivery into heart. Consistently, UTMD assisted exosomal delivery of siHomox1 nearly blocked the ferroptosis and the subsequent cardiotoxicity induced by doxorubicin. In summary, our findings reveal that the upregulation of HMOX1 induces ferroptosis in cardiomyocytes and UTMD-assisted exosomal delivery of siHmox1 can be used as a potential therapeutic strategy for DIC.


Asunto(s)
Doxorrubicina , Exosomas , Ferroptosis , Hemo-Oxigenasa 1 , Microburbujas , Miocitos Cardíacos , ARN Interferente Pequeño , Ferroptosis/efectos de los fármacos , Animales , Doxorrubicina/farmacología , Exosomas/metabolismo , Ratones , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Hemo-Oxigenasa 1/metabolismo , ARN Interferente Pequeño/farmacología , Ratones Endogámicos C57BL , Masculino , Sistemas de Liberación de Medicamentos , Cardiomiopatías/metabolismo , Proteínas de la Membrana
4.
J Nanobiotechnology ; 22(1): 528, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39218888

RESUMEN

Molecular ultrasound imaging with actively targeted microbubbles (MB) proved promising in preclinical studies but its clinical translation is limited. To achieve this, it is essential that the actively targeted MB can be produced with high batch-to-batch reproducibility with a controllable and defined number of binding ligands on the surface. In this regard, poly (n-butyl cyanoacrylate) (PBCA)-based polymeric MB have been used for US molecular imaging, however, ligand coupling was mostly done via hydrolysis and carbodiimide chemistry, which is a multi-step procedure with poor reproducibility and low MB yield. Herein, we developed a single-step coupling procedure resulting in high MB yields with minimal batch-to-batch variation. Actively targeted PBCA-MB were generated using an aminolysis protocol, wherein amine-containing cRGD was added to the MB using lithium methoxide as a catalyst. We confirmed the successful conjugation of cRGD on the MB surface, while preserving their structure and acoustic signal. Compared to the conventional hydrolysis protocol, aminolysis resulted in higher MB yields and better reproducibility of coupling efficiency. Optical imaging revealed that under flow conditions, cRGD- and rhodamine-labelled MB, generated by aminolysis, specifically bind to tumor necrosis factor-alpha (TNF-α) activated endothelial cells in vitro. Furthermore, US molecular imaging demonstrated a markedly higher binding of the cRGD-MB than of control MB in TNF-α activated mouse aortas and 4T1 tumors in mice. Thus, using the aminolysis based conjugation approach, important refinements on the production of cRGD-MB could be achieved that will facilitate the production of clinical-scale formulations with excellent binding and ultrasound imaging performance.


Asunto(s)
Enbucrilato , Microburbujas , Imagen Molecular , Ultrasonografía , Animales , Enbucrilato/química , Ratones , Imagen Molecular/métodos , Ultrasonografía/métodos , Humanos , Medios de Contraste/química , Femenino , Células Endoteliales de la Vena Umbilical Humana , Ratones Endogámicos BALB C , Línea Celular Tumoral , Factor de Necrosis Tumoral alfa/metabolismo
5.
Ultrasonics ; 144: 107449, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39217855

RESUMEN

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is marked by the deterioration of both cortical and spinal cord motor neurons. Despite the underlying causes of the disease remain elusive, there has been a growing attention on the well-being of cortical motor neurons in recent times. Focused ultrasound combined with microbubbles (FUS/MB) for opening the blood-brain barrier (BBB) provides a means for drug delivery to specific brain regions, holding significant promise for the treatment of neurological disorders. OBJECTIVES: We aim to explore the outcomes of FUS/MB-mediated delivery of arctiin (Arc), a natural compound with anti-inflammatory activities, to the cerebral motor cortex area by using a transgenic ALS mouse model. METHODS: The ALS mouse model with the SOD1G93A mutation was used and subjected to daily Arc administration with FUS/MB treatment twice a week. After six-week treatments, the motor performance was assessed by grip strength, wire hanging, and climbing-pole tests. Mouse brains, spinal cords and gastrocnemius muscle were harvested for histological staining. RESULTS: Compared with the mice given Arc administration only, the combined treatments of FUS/MB with Arc induced further mitigation of the motor function decline, accompanied by improved health of the gastrocnemius muscle. Furthermore, notable neuroprotective effect was evidenced by the amelioration of motor neuron failure in the cortex and lumbar spinal cord. CONCLUSION: These preliminary results indicated that the combined treatment of FUS/MB and arctiin exerted a potentially beneficial effect on neuromuscular function in the ALS disease.


Asunto(s)
Esclerosis Amiotrófica Lateral , Modelos Animales de Enfermedad , Ratones Transgénicos , Corteza Motora , Animales , Ratones , Corteza Motora/efectos de los fármacos , Corteza Motora/fisiopatología , Glucósidos/farmacología , Glucósidos/administración & dosificación , Microburbujas , Sistemas de Liberación de Medicamentos , Terapia por Ultrasonido/métodos , Superóxido Dismutasa-1/genética , Furanos/farmacología , Furanos/administración & dosificación , Masculino , Mutación
6.
Nat Commun ; 15(1): 8021, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39271721

RESUMEN

Microbubble-enhanced ultrasound provides a noninvasive physical method to locally overcome major obstacles to the accumulation of blood-borne therapeutics in the brain, posed by the blood-brain barrier (BBB). However, due to the highly nonlinear and coupled behavior of microbubble dynamics in brain vessels, the impact of microbubble resonant effects on BBB signaling and function remains undefined. Here, combined theoretical and prospective experimental investigations reveal that microbubble resonant effects in brain capillaries can control the enrichment of inflammatory pathways that are sensitive to wall shear stress and promote differential expression of a range of transcripts in the BBB, supporting the notion that microbubble dynamics exerted mechanical stress can be used to establish molecular, in addition to spatial, therapeutic windows to target brain diseases. Consistent with these findings, a robust increase in cytotoxic T-cell accumulation in brain tumors was observed, demonstrating the functional relevance and potential clinical significance of the observed immuno-mechano-biological responses.


Asunto(s)
Barrera Hematoencefálica , Encéfalo , Microburbujas , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/efectos de la radiación , Animales , Encéfalo/metabolismo , Encéfalo/irrigación sanguínea , Encéfalo/diagnóstico por imagen , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Inflamación/metabolismo , Ratones , Humanos , Estrés Mecánico , Ondas Ultrasónicas , Masculino , Capilares/metabolismo , Femenino
7.
Sci Rep ; 14(1): 20929, 2024 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-39251665

RESUMEN

Transarterial chemoembolization (TACE) is an image-guided minimally invasive treatment for liver cancer which involves delivery of chemotherapy and embolic material into tumor-supplying arteries to block blood flow to a liver tumor and to deliver chemotherapy directly to the tumor. However, the released drug diffuses only less than a millimeter away from the beads. To enhance the efficacy of TACE, the development of microbubbles electrostatically bound to the surface of drug-eluting beads loaded with different amounts of doxorubicin (0-37.5 mg of Dox/mL of beads) is reported. Up to 400 microbubbles were bound to Dox-loaded beads (70-150 microns). This facilitated ultrasound imaging of the beads and increased the release rate of Dox upon exposure to high intensity focused ultrasound (HIFU). Furthermore, ultrasound exposure (1 MPa peak negative pressure) increased the distance at which Dox could be detected from beads embedded in a tissue-mimicking phantom, compared with a no ultrasound control.


Asunto(s)
Quimioembolización Terapéutica , Doxorrubicina , Sistemas de Liberación de Medicamentos , Microburbujas , Ultrasonografía , Doxorrubicina/administración & dosificación , Doxorrubicina/química , Sistemas de Liberación de Medicamentos/métodos , Quimioembolización Terapéutica/métodos , Ultrasonografía/métodos , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/terapia , Fantasmas de Imagen , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/química , Microesferas
8.
Comput Biol Med ; 181: 109061, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39186904

RESUMEN

Sonothrombolysis is a technique that employs the ultrasound waves to break down the clot. Recent studies have demonstrated significant improvement in the treatment efficacy when combining two ultrasound waves of different frequencies. Nevertheless, the findings remain conflicted on the ideal frequency pairing that leads to an optimal treatment outcome. Existing experimental studies are constrained by the limited range of frequencies that can be investigated, while numerical studies are typically confined to spherical microbubble dynamics, thereby restricting the scope of the analysis. To overcome this, the present study investigated the microbubble dynamics caused by the different combinations of ultrasound frequencies. This was carried out using computational modelling as it enables the visualisation of the microbubble behaviour, which is difficult in experimental studies due to the opacity of blood. The results showed that the pairings of two ultrasound waves with low frequencies generally produced stronger cavitation and higher flow-induced shear stress on the clot surface. However, one should avoid the frequency pairings that are integer multipliers of each other, i.e., frequency ratio of 1/3, 1/2 and 2, as they led to resultant wave with low pressure amplitude that weakened the cavitation. At 0.5 + 0.85 MHz, the microbubble caused the highest shear stress of 60.5 kPa, due to its large translational distance towards the clot. Although the pressure threshold for inertial cavitation was reduced using dual-frequency ultrasound, the impact of the high-speed jet can only be realised when the microbubble travelled close to the clot. The results obtained from the present study provide groundwork for deeper understanding on the microbubble dynamics during dual-frequency sonothrombolysis, which is of paramount importance for its optimisations and the subsequent clinical translation.


Asunto(s)
Simulación por Computador , Microburbujas , Terapia por Ultrasonido , Humanos , Terapia por Ultrasonido/métodos , Modelos Cardiovasculares , Trombosis/diagnóstico por imagen
9.
Ultrason Sonochem ; 109: 107005, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39098097

RESUMEN

Experimental studies have shown that ultrasonic cavitation can reversibly open the blood-brain barrier (BBB) to assist drug delivery. Nevertheless, the majority of the present study focused on experimental aspects of BBB opening. In this study, we developed a three-bubble-liquid-solid model to investigate the dynamic behavior of multiple bubbles within the blood vessels, and elucidate the physical mechanism of drug molecules through endothelial cells under ultrasonic cavitation excitation. The results showed that the large bubbles have a significant inhibitory effect on the movement of small bubbles, and the vibration morphology of intravascular microbubbles was affected by the acoustic parameters, microbubble size, and the distance between the microbubbles. The ultrasonic cavitation can significantly enhance the unidirectional flux of drug molecules, and the unidirectional flux growth rate of the wall can reach more than 5 %. Microjets and shock waves emitted from microbubbles generate different stress distribution patterns on the vascular wall, which in turn affects the pore size of the vessel wall and the permeability of drug molecules. The vibration morphology of microbubbles is related to the concentration, arrangement and scale of microbubbles, and the drug permeation impact can be enhanced by optimizing bubble size and acoustic parameters. The results offer an extensive depiction of the factors influencing the blood-brain barrier opening through ultrasonic cavitation, and the model may provide a potential technique to actively regulate the penetration capacity of drugs through endothelial layer of the neurovascular system by regulating BBB opening.


Asunto(s)
Barrera Hematoencefálica , Microburbujas , Ondas Ultrasónicas , Barrera Hematoencefálica/metabolismo , Simulación por Computador , Modelos Biológicos
10.
Cardiovasc Ultrasound ; 22(1): 10, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39118073

RESUMEN

From its inception as a two-dimensional snapshot of the beating heart, echocardiography has become an indelible part of cardiovascular diagnostics. The integration of ultrasound enhancing agents (UEAs) marks a pivotal transition, enhancing its diagnostic acumen beyond myocardial perfusion. These agents have refined echocardiography's capacity to visualize complex cardiac anatomy and pathology with unprecedented clarity, especially in non-coronary artery disease contexts. UEAs aid in detailed assessments of myocardial viability, endocardial border delineation in left ventricular opacification, and identification of intracardiac masses. Recent innovations in UEAs, accompanied by advancements in echocardiographic technology, offer clinicians a more nuanced view of cardiac function and blood flow dynamics. This review explores recent developments in these applications and future contemplated studies.


Asunto(s)
Medios de Contraste , Ecocardiografía , Humanos , Ecocardiografía/métodos , Enfermedades Cardiovasculares/diagnóstico por imagen , Enfermedades Cardiovasculares/diagnóstico , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/fisiopatología , Aumento de la Imagen/métodos , Microburbujas
11.
Theranostics ; 14(11): 4519-4535, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39113808

RESUMEN

Background : Focused ultrasound (FUS) in combination with microbubbles has recently shown great promise in facilitating blood-brain barrier (BBB) opening for drug delivery and immunotherapy in Alzheimer's disease (AD). However, it is currently limited to systems integrated within the MRI suites or requiring post-surgical implants, thus restricting its widespread clinical adoption. In this pilot study, we investigate the clinical safety and feasibility of a portable, non-invasive neuronavigation-guided FUS (NgFUS) system with integrated real-time 2-D microbubble cavitation mapping. Methods : A phase 1 clinical study with mild to moderate AD patients (N = 6) underwent a single session of microbubble-mediated NgFUS to induce transient BBB opening (BBBO). Microbubble activity under FUS was monitored with real-time 2-D cavitation maps and dosing to ensure the efficacy and safety of the NgFUS treatment. Post-operative MRI was used for BBB opening and closure confirmation as well as safety assessment. Changes in AD biomarker levels in both blood serum and extracellular vesicles (EVs) were evaluated, while changes in amyloid-beta (Aß) load in the brain were assessed through 18F-florbetapir PET. Results : BBBO was achieved in 5 out of 6 subjects with an average volume of 983 ± 626 mm3 following FUS at the right frontal lobe both in white and gray matter regions. The outpatient treatment was completed within 34.8 ± 10.7 min. Cavitation dose significantly correlated with the BBBO volume (R 2 > 0.9, N = 4), demonstrating the portable NgFUS system's capability of predicting opening volumes. The cavitation maps co-localized closely with the BBBO location, representing the first report of real-time transcranial 2-D cavitation mapping in the human brain. Larger opening volumes correlated with increased levels of AD biomarkers, including Aß42 (R 2 = 0.74), Tau (R 2 = 0.95), and P-Tau181 (R 2 = 0.86), assayed in serum-derived EVs sampled 3 days after FUS (N = 5). From PET scans, subjects showed a lower Aß load increase in the treated frontal lobe region compared to the contralateral region. Reduction in asymmetry standardized uptake value ratios (SUVR) correlated with the cavitation dose (R 2 > 0.9, N = 3). Clinical changes in the mini-mental state examination over 6 months were within the expected range of cognitive decline with no additional changes observed as a result of FUS. Conclusion : We showed the safety and feasibility of this cost-effective and time-efficient portable NgFUS treatment for BBBO in AD patients with the first demonstration of real-time 2-D cavitation mapping. The cavitation dose correlated with BBBO volume, a slowed increase in pathology, and serum detection of AD proteins. Our study highlights the potential for accessible FUS treatment in AD, with or without drug delivery.


Asunto(s)
Enfermedad de Alzheimer , Barrera Hematoencefálica , Imagen por Resonancia Magnética , Microburbujas , Humanos , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/diagnóstico por imagen , Enfermedad de Alzheimer/terapia , Enfermedad de Alzheimer/diagnóstico por imagen , Masculino , Anciano , Femenino , Proyectos Piloto , Imagen por Resonancia Magnética/métodos , Péptidos beta-Amiloides/metabolismo , Persona de Mediana Edad , Biomarcadores/metabolismo , Sistemas de Liberación de Medicamentos/métodos , Anciano de 80 o más Años
12.
Bioresour Technol ; 411: 131253, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39128641

RESUMEN

Ultrasound-assisted extraction (UAE) shows great potential in exploiting microalgal compounds. However, upgrading the extraction system lacks concerns. This study proposes a novel sono-reactor featuring a microbubble distributor for increasing bubble abundance and correspondingly improving microalgal compound extraction. Results indicate that protein concentrations increase with ultrasound powers and extraction time while an optimized gas flow rate exists. The optimal parameters by Box-Behnken design are power 646.0 W, nitrogen flow rate 25.0 mL/min, and time 40.0 min, with an optimal protein concentration of 249.1 mg/L - a substantial improvement over gas-free extraction. The strategic increase in bubble abundance enhances microalgal compound extraction efficiency and extraction kinetics. The system innovation will contribute to the advancement of bioresource utilization and sustainability.


Asunto(s)
Microalgas , Microburbujas , Microalgas/metabolismo , Fraccionamiento Químico/métodos , Cinética , Sonicación/métodos
13.
Ultrasonics ; 144: 107446, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39213718

RESUMEN

Ultrasound Localization Microscopy (ULM) facilitates structural and hemodynamic imaging of microvessels with a resolution of tens of micrometers. In ULM, the extraction of effective microbubble signals is crucial for image quality. Singular Value Decomposition (SVD) is currently the most prevalent method for microbubble signal extraction in ULM. Most existing ULM studies employ a fixed SVD filter threshold using empirical values which will lead to imaging quality degradation due to the insufficient separation of blood signals. In this study, we propose an adaptive and non-threshold SVD filter based on canopy-density clustering, termed DCC-SVD. This filter automatically classifies the components of the SVD based on the density of their spatiotemporal features, eliminating the need for parameter selection. In in vitro tube phantom, DCC-SVD demonstrated its ability to adaptive separation of blood and bubble signal at varying microbubble concentrations and flow rates. We compared the proposed DCC-SVD method with the Block-match 3D (BM3D) filter and a classical adaptive method called spatial similarity matrix (SSM), using concentration-variable in vivo rat brain data, as well as open-source rat kidney and mouse tumor datasets. The proposed DCC-SVD improved the global spatial resolution by approximately 4 µm from 30.39 µm to 26.02 µm. It also captured vessel structure absent in images obtained by other methods and yielded a smoother vessel intensity profile, making it a promising spatiotemporal filter for ULM imaging.


Asunto(s)
Microburbujas , Fantasmas de Imagen , Animales , Ratas , Ratones , Procesamiento de Imagen Asistido por Computador/métodos , Microscopía Acústica/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/irrigación sanguínea , Algoritmos , Riñón/diagnóstico por imagen , Riñón/irrigación sanguínea , Medios de Contraste
14.
Artículo en Inglés | MEDLINE | ID: mdl-39088497

RESUMEN

Tracking and controlling microbubble (MB) dynamics in the human brain through acoustic emission (AE) monitoring during transcranial focused ultrasound (tFUS) therapy are critical for attaining safe and effective treatments. The low-amplitude MB emissions have harmonic and ultra-harmonic components, necessitating a broad bandwidth and low-noise system for monitoring transcranial MB activity. Capacitive micromachined ultrasonic transducers (CMUTs) offer high sensitivity and low noise over a broad bandwidth, especially when they are tightly integrated with electronics, making them a good candidate technology for monitoring the MB activity through human skull. In this study, we designed a 16-channel analog front-end (AFE) electronics with a low-noise transimpedance amplifier (TIA), a band-gap reference circuit, and an output buffer stage. To assess AFE performance and ability to detect MB AE, we combined it with a commercial CMUT array. The integrated system has 12.3 - [Formula: see text] receive sensitivity with 0.085 - [Formula: see text] minimum detectable pressure (MDP) up to 3 MHz for a single element CMUT with 3.78 [Formula: see text] area. Experiments with free MBs in a microfluidic channel demonstrate that our system is able to capture key spectral components of MBs' harmonics when sonicated at clinically relevant frequencies (0.5 MHz) and pressures (250 kPa). Together our results demonstrate that the proposed CMUT system can support the development of novel passive cavitation detectors (PCD) to track MB activity for attaining safe and effective focused ultrasound (FUS) treatments.


Asunto(s)
Diseño de Equipo , Microburbujas , Transductores , Humanos , Ultrasonido Enfocado de Alta Intensidad de Ablación/instrumentación , Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Procesamiento de Señales Asistido por Computador/instrumentación , Fantasmas de Imagen
15.
J Acoust Soc Am ; 156(2): 1004-1016, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39136631

RESUMEN

Contrast ultrasound (CUS) has received much interest because of its sensitivity enhancement for blood flow imaging. However, there is still a lack of nonlinear simulation method for CUS, as conventional simulators cannot deal with the microbubble acoustic nonlinearity. In this paper, a nonlinear simulation method of CUS is developed based on a combination strategy of the k-space pseudospectral method and Rayleigh-Plesset Marmottant model. Different contrast pulse sequence strategies as well as the radial modulation imaging are simulated and compared using the proposed method. For blood flow imaging, simulations under different scenarios such as power Doppler and ultrasound localization microscopy are also carried out. Furthermore, a face-to-face comparison is performed between simulations and phantom experiments to validate the proposed method.


Asunto(s)
Simulación por Computador , Medios de Contraste , Dinámicas no Lineales , Fantasmas de Imagen , Ultrasonografía , Medios de Contraste/administración & dosificación , Ultrasonografía/métodos , Microburbujas , Humanos
16.
PLoS One ; 19(8): e0308075, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39088581

RESUMEN

Nitric oxide (NO) regulates vascular homeostasis and plays a key role in revascularization and angiogenesis. The endothelial nitric oxide synthase (eNOS) enzyme catalyzes NO production in endothelial cells. Overexpression of the eNOS gene has been implicated in pathologies with dysfunctional angiogenic processes, such as cancer. Therefore, modulating eNOS gene expression using small interfering RNAs (siRNAs) represents a viable strategy for antitumor therapy. siRNAs are highly specific to the target gene, thus reducing off-target effects. Given the widespread distribution of endothelium and the crucial physiological role of eNOS, localized delivery of nucleic acid to the affected area is essential. Therefore, the development of an efficient eNOS-siRNA delivery carrier capable of controlled release is imperative for targeting specific vascular regions, particularly those associated with tumor vascular growth. Thus, this study aims to utilize ultrasound-mediated microbubble destruction (UMMD) technology with cationic microbubbles loaded with eNOS-siRNA to enhance transfection efficiency and improve siRNA delivery, thereby preventing sprouting angiogenesis. The efficiency of eNOS-siRNA transfection facilitated by UMMD was assessed using bEnd.3 cells. Synthesis of nitric oxide and eNOS protein expression were also evaluated. The silencing of eNOS gene in a model of angiogenesis was assayed using the rat aortic ring assay. The results showed that from 6 to 24 h, the transfection of fluorescent siRNA with UMMD was twice as high as that of lipofection. Moreover, transfection of eNOS-siRNA with UMMD enhanced the knockdown level (65.40 ± 4.50%) compared to lipofectamine (40 ± 1.70%). Silencing of eNOS gene with UMMD required less amount of eNOS-siRNA (42 ng) to decrease the level of eNOS protein expression (52.30 ± 0.08%) to the same extent as 79 ng of eNOS-siRNA using lipofectamine (56.30 ± 0.10%). NO production assisted by UMMD was reduced by 81% compared to 67% reduction transfecting with lipofectamine. This diminished NO production led to higher attenuation of aortic ring outgrowth. Three-fold reduction compared to lipofectamine transfection. In conclusion, we propose the combination of eNOS-siRNA and UMMD as an efficient, safe, non-viral nucleic acid transfection strategy for inhibition of tumor progression.


Asunto(s)
Aorta , Microburbujas , Óxido Nítrico Sintasa de Tipo III , Óxido Nítrico , ARN Interferente Pequeño , Transfección , Animales , Óxido Nítrico Sintasa de Tipo III/metabolismo , Óxido Nítrico Sintasa de Tipo III/genética , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Ratas , Transfección/métodos , Aorta/metabolismo , Óxido Nítrico/metabolismo , Ratones , Masculino , Línea Celular , Neovascularización Fisiológica/genética
17.
Fluids Barriers CNS ; 21(1): 65, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39138578

RESUMEN

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a rapidly progressing neurodegenerative disorder with minimally effective treatment options. An important hurdle in ALS drug development is the non-invasive therapeutic access to the motor cortex currently limited by the presence of the blood-brain barrier (BBB). Focused ultrasound and microbubble (FUS+ MB) treatment is an emerging technology that was successfully used in ALS patients to temporarily open the cortical BBB. However, FUS+ MB-mediated drug delivery across ALS patients' BBB has not yet been reported. Similarly, the effects of FUS+ MB on human ALS BBB cells remain unexplored. METHODS: Here we established the first FUS+ MB-compatible, fully-human ALS patient-cell-derived BBB model based on induced brain endothelial-like cells (iBECs) to study anti-TDP-43 antibody delivery and FUS+ MB bioeffects in vitro. RESULTS: Generated ALS iBECs recapitulated disease-specific hallmarks of BBB pathology, including reduced BBB integrity and permeability, and TDP-43 proteinopathy. The results also identified differences between sporadic ALS and familial (C9orf72 expansion carrying) ALS iBECs reflecting patient heterogeneity associated with disease subgroups. Studies in these models revealed successful ALS iBEC monolayer opening in vitro with no adverse cellular effects of FUS+ MB as reflected by lactate dehydrogenase (LDH) release viability assay and the lack of visible monolayer damage or morphology change in FUS+ MB treated cells. This was accompanied by the molecular bioeffects of FUS+ MB in ALS iBECs including changes in expression of tight and adherens junction markers, and drug transporter and inflammatory mediators, with sporadic and C9orf72 ALS iBECs generating transient specific responses. Additionally, we demonstrated an effective increase in the delivery of anti-TDP-43 antibody with FUS+ MB in C9orf72 (2.7-fold) and sporadic (1.9-fold) ALS iBECs providing the first proof-of-concept evidence that FUS+ MB can be used to enhance the permeability of large molecule therapeutics across the BBB in a human ALS in vitro model. CONCLUSIONS: Together, this study describes the first characterisation of cellular and molecular responses of ALS iBECs to FUS+ MB and provides a fully-human platform for FUS+ MB-mediated drug delivery screening on an ALS BBB in vitro model.


Asunto(s)
Esclerosis Amiotrófica Lateral , Barrera Hematoencefálica , Proteínas de Unión al ADN , Microburbujas , Esclerosis Amiotrófica Lateral/metabolismo , Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/efectos de los fármacos , Humanos , Proteínas de Unión al ADN/metabolismo , Sistemas de Liberación de Medicamentos/métodos , Células Endoteliales/metabolismo , Anticuerpos/administración & dosificación , Ondas Ultrasónicas , Células Cultivadas
18.
Int J Mol Sci ; 25(13)2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-39000202

RESUMEN

The nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 4 (NOX4) protein plays an essential role in the cisplatin (CDDP)-induced generation of reactive oxygen species (ROS). In this study, we evaluated the suitability of ultrasound-mediated lysozyme microbubble (USMB) cavitation to enhance NOX4 siRNA transfection in vitro and ex vivo. Lysozyme-shelled microbubbles (LyzMBs) were constructed and designed for siNOX4 loading as siNOX4/LyzMBs. We investigated different siNOX4-based cell transfection approaches, including naked siNOX4, LyzMB-mixed siNOX4, and siNOX4-loaded LyzMBs, and compared their silencing effects in CDDP-treated HEI-OC1 cells and mouse organ of Corti explants. Transfection efficiencies were evaluated by quantifying the cellular uptake of cyanine 3 (Cy3) fluorescein-labeled siRNA. In vitro experiments showed that the high transfection efficacy (48.18%) of siNOX4 to HEI-OC1 cells mediated by US and siNOX4-loaded LyzMBs significantly inhibited CDDP-induced ROS generation to almost the basal level. The ex vivo CDDP-treated organ of Corti explants of mice showed an even more robust silencing effect of the NOX4 gene in the siNOX4/LyzMB groups treated with US sonication than without US sonication, with a marked abolition of CDDP-induced ROS generation and cytotoxicity. Loading of siNOX4 on LyzMBs can stabilize siNOX4 and prevent its degradation, thereby enhancing the transfection and silencing effects when combined with US sonication. This USMB-derived therapy modality for alleviating CDDP-induced ototoxicity may be suitable for future clinical applications.


Asunto(s)
Cisplatino , Células Ciliadas Auditivas , Microburbujas , Muramidasa , NADPH Oxidasa 4 , Ototoxicidad , Especies Reactivas de Oxígeno , Cisplatino/farmacología , Animales , NADPH Oxidasa 4/genética , NADPH Oxidasa 4/metabolismo , Ratones , Células Ciliadas Auditivas/efectos de los fármacos , Células Ciliadas Auditivas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Ototoxicidad/genética , Muramidasa/genética , ARN Interferente Pequeño/genética , Ondas Ultrasónicas , Técnicas de Silenciamiento del Gen , Línea Celular
19.
Nanotheranostics ; 8(4): 427-441, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38961889

RESUMEN

Background: The blood-brain barrier (BBB) is a major bottleneck in delivering therapeutics to the brain. Treatment strategies to transiently open this barrier include focused ultrasound combined with intravenously injected microbubbles (FUS+MB) and targeting of molecules that regulate BBB permeability. Methods: Here, we investigated BBB opening mediated by the claudin-5 binder cCPEm (a microorganismal toxin in a truncated form) and FUS+MB at a centre frequency of 1 MHz, assessing dextran uptake, broadband emission, and endogenous immunoglobulin G (IgG) extravasation. Results: FUS+MB-induced BBB opening was detectable at a pressure ≥0.35 MPa when assessed for leakage of 10 and 70 kDa dextran, and at ≥0.2 MPa for uptake of endogenous IgG. Treating mice with 20 mg/kg cCPEm failed to open the BBB, and pre-treatment with cCPEm followed by FUS+MB at 0.2 and 0.3 MPa did not overtly increase BBB opening compared to FUS+MB alone. Using passive cavitation detection (PCD), we found that broadband emission correlated with the peak negative pressure (PNP) and dextran leakage, indicating the possibility of using broadband emission for developing a feedback controller to monitor BBB opening. Conclusions: Together, our study highlights the challenges in developing combinatorial approaches to open the BBB and presents an additional IgG-based histological detection method for BBB opening.


Asunto(s)
Barrera Hematoencefálica , Claudina-5 , Microburbujas , Animales , Barrera Hematoencefálica/metabolismo , Ratones , Claudina-5/metabolismo , Inmunoglobulina G/metabolismo , Ondas Ultrasónicas , Ratones Endogámicos C57BL , Dextranos/química , Dextranos/farmacocinética
20.
Ultrasound Med Biol ; 50(10): 1494-1505, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39054243

RESUMEN

OBJECTIVE: The goal of this study was to evaluate the performance of different commercial ultrasound contrast microbubbles (MBs) when measuring bladder phantom pressure with sub-harmonic-aided pressure estimation (SHAPE) methodology. We hypothesized that SHAPE performance is dependent on MB formulation. This study aimed to advance the SHAPE application for bladder pressure measurements in humans. METHODS: Using a previously designed and built bladder phantom, we tested four different commercial agents: Definity, Lumason, Sonazoid and Optison. A standard clinical cystometrogram (CMG) system was used to infuse a MB-saline mixture into the bladder phantom to measure pressure. Ultrasound imaging was performed using the GE Healthcare LOGIQ E10 scanner. RESULTS: All agents showed a predicted inverse linear relationship between change in pressure and SHAPE signal. However, they differ from each other in terms of stability, linear correlation, sensitivity to pressure and error. Generally, Definity and Lumason showed the highest performance during the SHAPE-based bladder phantom pressure assessments. CONCLUSION: Our results show that the SHAPE signal decreases as bladder phantom pressures increases, regardless of the agent or CMG phase, suggesting the possibility of using SHAPE for measuring bladder pressure without a catheter. However, the efficacy of SHAPE in measuring pressure varies by MB formulation. These observations support using Lumason and Definity in a human subject feasibility study as we advance toward a catheter-free solution for measuring voiding bladder pressure via SHAPE.


Asunto(s)
Medios de Contraste , Fluorocarburos , Microburbujas , Fantasmas de Imagen , Presión , Ultrasonografía , Vejiga Urinaria , Vejiga Urinaria/diagnóstico por imagen , Ultrasonografía/métodos , Humanos , Hierro , Compuestos Férricos , Óxidos , Reproducibilidad de los Resultados , Albúminas
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