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1.
Int J Biol Macromol ; 276(Pt 2): 134067, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39038579

RESUMO

The effect of ultrasound/CaCl2 co-treatment on aggregation structure, thermal stability, rheological, and film properties of high amylose corn starch (HACS) was investigated. The scanning electron microscopy (SEM) images revealed the number of starch fragments and malformed starch granules increased after co-treatment. The differential scanning calorimetry (DSC) results showed the co-treated HACS got a lower gelatinization temperature (92.65 ± 0.495 °C) and enthalpy values (ΔH, 4.14 ± 0.192 J/g). The optical microscope images indicated that lesser Maltase crosses were observed in co-treated HACS. The results of X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) indicated ultrasound influenced the compactness of amorphous zone and CaCl2 damaged the crystalline region of HACS granules. Additionally, the rheology properties of HACS dispersion demonstrated the apparent viscosity of co-treated dispersion increased as the ultrasound time prolonged. The mechanical strength and structural compactness of HACS films were improved after ultrasound treatment. The mechanism of ultrasound/CaCl2 co-treatment improved the gelatinization and film-forming ability of HACS was that (i) ultrasound wave loosened the HACS granules shell, promoted the treatment of CaCl2 on HACS granules, and (ii) ultrasound wave improved the uniform distribution of HACS dispersion, increased the interaction between CaCl2 and starch chains during the process of film-forming.

2.
J Pain Res ; 17: 2063-2070, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38881759

RESUMO

Purpose: Emerging evidence suggests that although Horner's syndrome manifests observable facial changes, it may not comprehensively evaluate the hemodynamic alterations associated with stellate ganglion block (SGB). This study endeavors to systematically evaluate the influence of SGB on the elasticity and flow velocity of the common carotid artery (CCA) and brachial artery utilizing ultrasound wave intensity analysis (usWIA). Particularly, it focuses on patients necessitating monitoring for its effects on specific organs or regions. Methods: Totally, we selected 33 patients, where only 31 patients (comprising 15 males and 16 females) were included between September 2020 to January 2022 after screening patients who require SGB treatment for painful disorders. The side on which the SGB was administered depended on the patient's painful side, 13 cases underwent left stellate ganglion block (LSGB), and 18 cases underwent right stellate ganglion block (RSGB). Wave intensity (WI) data were collected by usWIA on the CCA and brachial artery before the administration of SGB and after the manifestation of Horner's syndrome. We then compared the changes in these data pre- and post-SGB using SPSS 26.0. Results: The results showed an increase in arterial compliance (AC) of the CCA and brachial artery on the blocked side after SGB (P < 0.05). In contrast, pressure-strain elastic modulus (EP) and arterial stiffness pulse wave velocity (PWVß) decreased (for all P < 0.05). Furthermore, the minimum velocity (Vmin) of the CCA exhibited a significant increase (P < 0.01), while wave intensity pulse wave velocity (PWVwi) was significantly reduced (P < 0.01). In contrast, on the contralateral side of the CCA, EP and PWVß increased after SGB (for all P < 0.05), while AC decreased (P < 0.05). Conclusion: SGB has been observed to enhance the elasticity and blood flow velocity of arteries within its innervated areas. In clinical practice, usWIA can serve as an objective measurement tool for assessing the impact of SGB on arterial elasticity and flow velocity in specific organs or regions. Furthermore, unilateral SGB has been noted to diminish the arterial elasticity of the CCA on the contralateral side.


QUESTION: How to accurately and objectively evaluate the hemodynamic changes of SGB on targeted organs or regions? FINDINGS: SGB increased the elasticity and blood flow velocity of the arteries on the blocked side by usWIA. Meaning: The usWIA could serve as an objective measurement tool for assessing the effects of SGB on arterial elasticity and blood flow velocity, especially for patients needing evaluation of its impact on the upper limbs.

3.
Front Bioeng Biotechnol ; 12: 1394373, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38720878

RESUMO

Introduction: There is clinical evidence that the fresh blood viscosity is an important indicator in the development of vascular disorder and coagulation. However, existing clinical viscosity measurement techniques lack the ability to measure blood viscosity and replicate the in-vivo hemodynamics simultaneously. Methods: Here, we fabricate a novel digital device, called Tesla valves and ultrasound waves-powered blood plasma viscometer (TUBPV) which shows capacities in both viscosity measurement and coagulation monitoring. Results: Based on the Hagen-Poiseuille equation, viscosity analysis can be faithfully performed by a video microscopy. Tesla-like channel ensured unidirectional liquid motion with stable pressure driven that was triggered by the interaction of Tesla valve structure and ultrasound waves. In few seconds the TUBPV can generate an accurate viscosity profile on clinic fresh blood samples from the flow time evaluation. Besides, Tesla-inspired microchannels can be used in the real-time coagulation monitoring. Discussion: These results indicate that the TUBVP can serve as a point-of-care device in the ICU to evaluate the blood's viscosity and the anticoagulation treatment.

4.
Int J Nanomedicine ; 19: 2529-2552, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38505170

RESUMO

The blood-brain barrier (BBB) and blood-tumor barrier (BTB) pose substantial challenges to efficacious drug delivery for glioblastoma multiforme (GBM), a primary brain tumor with poor prognosis. Nanoparticle-based combinational strategies have emerged as promising modalities to overcome these barriers and enhance drug penetration into the brain parenchyma. This review discusses various nanoparticle-based combinatorial approaches that combine nanoparticles with cell-based drug delivery, viral drug delivery, focused ultrasound, magnetic field, and intranasal drug delivery to enhance drug permeability across the BBB and BTB. Cell-based drug delivery involves using engineered cells as carriers for nanoparticles, taking advantage of their intrinsic migratory and homing capabilities to facilitate the transport of therapeutic payloads across BBB and BTB. Viral drug delivery uses engineered viral vectors to deliver therapeutic genes or payloads to specific cells within the GBM microenvironment. Focused ultrasound, coupled with microbubbles or nanoparticles, can temporarily disrupt the BBB to increase drug permeability. Magnetic field-guided drug delivery exploits magnetic nanoparticles to facilitate targeted drug delivery under an external magnetic field. Intranasal drug delivery offers a minimally invasive avenue to bypass the BBB and deliver therapeutic agents directly to the brain via olfactory and trigeminal pathways. By combining these strategies, synergistic effects can enhance drug delivery efficiency, improve therapeutic efficacy, and reduce off-target effects. Future research should focus on optimizing nanoparticle design, exploring new combination strategies, and advancing preclinical and clinical investigations to promote the translation of nanoparticle-based combination therapies for GBM.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Nanopartículas , Humanos , Barreira Hematoencefálica , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Sistemas de Liberação de Medicamentos , Encéfalo/metabolismo , Nanopartículas/metabolismo , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Microambiente Tumoral
5.
Ultrasonics ; 131: 106961, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36812819

RESUMO

Sonothrombolysis is a technique that utilises ultrasound waves to excite microbubbles surrounding a clot. Clot lysis is achieved through mechanical damage induced by acoustic cavitation and through local clot displacement induced by acoustic radiation force (ARF). Despite the potential of microbubble-mediated sonothrombolysis, the selection of the optimal ultrasound and microbubble parameters remains a challenge. Existing experimental studies are not able to provide a complete picture of how ultrasound and microbubble characteristics influence the outcome of sonothrombolysis. Likewise, computational studies have not been applied in detail in the context of sonothrombolysis. Hence, the effect of interaction between the bubble dynamics and acoustic propagation on the acoustic streaming and clot deformation remains unclear. In the present study, we report for the first time the computational framework that couples the bubble dynamic phenomena with the acoustic propagation in a bubbly medium to simulate microbubble-mediated sonothrombolysis using a forward-viewing transducer. The computational framework was used to investigate the effects of ultrasound properties (pressure and frequency) and microbubble characteristics (radius and concentration) on the outcome of sonothrombolysis. Four major findings were obtained from the simulation results: (i) ultrasound pressure plays the most dominant role over all the other parameters in affecting the bubble dynamics, acoustic attenuation, ARF, acoustic streaming, and clot displacement, (ii) smaller microbubbles could contribute to a more violent oscillation and improve the ARF simultaneously when they are stimulated at higher ultrasound pressure, (iii) higher microbubbles concentration increases the ARF, and (iv) the effect of ultrasound frequency on acoustic attenuation is dependent on the ultrasound pressure. These results may provide fundamental insight that is crucial in bringing sonothrombolysis closer to clinical implementation.


Assuntos
Simulação por Computador , Procedimentos Endovasculares , Trombólise Mecânica , Microbolhas , Trombólise Mecânica/métodos , Ultrassom , Acústica
6.
Adv Sci (Weinh) ; 10(11): e2205141, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36683241

RESUMO

The recent application of the internet of things demands the ubiquitous utilization of data and electrical power. Even with the development of a wide variety of energy-harvesting technologies, few studies have reported a device transporting electrical energy and data simultaneously. This paper reports an electrostatic induction nanogenerator (ESING) consisting of a one-dimensional metastructure that can modulate the output voltage based on the resonance of ultrasound waves to transmit energy and data simultaneously. The ESING device is fabricated using electronegative poly(vinylidene fluoride) (PVDF) membrane using a phase inversion process. The output voltage from the ESING device exhibits periodic resonant peaks as the gap between the PVDF membrane and the Al electrode changes, showing an up to 35-fold difference between the maximum and minimum output voltages depending on the resonance state. The energy and electrical signal can be transmitted simultaneously in free space because the ESING converts energy from high-frequency ultrasound waves. This paper provides proof of concept for a data and energy-transferable smart tag device based on ESING devices exhibiting resonant and non-resonant states. A device consisting of four ESINGs for a 4-bit signal is implemented to demonstrate 16 signals.

7.
Comput Methods Biomech Biomed Engin ; 26(10): 1134-1139, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35971823

RESUMO

We develop computational models of bone growth in ultrasonically stimulated porous tissue scaffolds with uniform square pores and a bioinspired structure. While bone growth in the bioinspired scaffolds is slower, it produces amounts of bone comparable to the square pore scaffold, making the bioinspired structure ideal for enhancing bone growth with better structural integrity. Controlling the initial mesenchymal stem cell distribution in the scaffolds also affects the growth rate and total bone formation, which could be further useful for controlling bone growth in the scaffold based on an individual's physiology.


Assuntos
Osteogênese , Alicerces Teciduais , Alicerces Teciduais/química , Osso e Ossos , Engenharia Tecidual , Porosidade
8.
BMC Cancer ; 21(1): 981, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34470602

RESUMO

BACKGROUND: Paclitaxel (Taxol) is a microtubule-stabilizing drug used to treat several solid tumors, including ovarian, breast, non-small cell lung, and pancreatic cancers. The current treatment of ovarian cancer is chemotherapy using paclitaxel in combination with carboplatin as a frontline agent, and paclitaxel is also used in salvage treatment as a second line drug with a dose intensive regimen following recurrence. More recently, a dose dense approach for paclitaxel has been used to treat metastatic breast cancer with success. Paclitaxel binds to beta tubulin with high affinity and stabilizes microtubule bundles. As a consequence of targeting microtubules, paclitaxel kills cancer cells through inhibition of mitosis, causing mitotic catastrophes, and by additional, not yet well defined non-mitotic mechanism(s). RESULTS: In exploring methods to modulate activity of paclitaxel in causing cancer cell death, we unexpectedly found that a brief exposure of paclitaxel-treated cells in culture to low intensity ultrasound waves prevented the paclitaxel-induced cytotoxicity and death of the cancer cells. The treatment with ultrasound shock waves was found to transiently disrupt the microtubule cytoskeleton and to eliminate paclitaxel-induced rigid microtubule bundles. When cellular microtubules were labelled with a fluorescent paclitaxel analog, exposure to ultrasound waves led to the disassembly of the labeled microtubules and localization of the signals to perinuclear compartments, which were determined to be lysosomes. CONCLUSIONS: We suggest that ultrasound disrupts the paclitaxel-induced rigid microtubule cytoskeleton, generating paclitaxel bound fragments that undergo degradation. A new microtubule network forms from tubulins that are not bound by paclitaxel. Hence, ultrasound shock waves are able to abolish paclitaxel impact on microtubules. Thus, our results demonstrate that a brief exposure to low intensity ultrasound can reduce and/or eliminate cytotoxicity associated with paclitaxel treatment of cancer cells in cultures.


Assuntos
Neoplasias da Mama/patologia , Microtúbulos/patologia , Mitose , Neoplasias Ovarianas/patologia , Paclitaxel/farmacologia , Ondas Ultrassônicas , Antineoplásicos Fitogênicos/farmacologia , Apoptose , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/radioterapia , Proliferação de Células , Citoesqueleto/metabolismo , Feminino , Humanos , Microtúbulos/efeitos dos fármacos , Microtúbulos/efeitos da radiação , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/radioterapia , Tubulina (Proteína)/metabolismo , Células Tumorais Cultivadas
9.
Photodiagnosis Photodyn Ther ; 33: 102139, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33310015

RESUMO

Photothermal and ultrasound therapies are novel non-invasive strategies for tumor treatment which are equipped with a photosensitizer and sonosensitizer subsequent activation by laser irradiation and ultrasound exposure. In this study, curcumin-gold-polyethylene glycol nanoparticles (Cur-Au NPs-PEG) were synthesized, and the dual role in photothermal (PTT) and sonodynamic (SDT) therapies of melanoma cancer was evaluated. The toxicity effect of Cur-Au NPs-PEG against a mouse malignant melanoma cell line C540 (B16/F10) was firstly inspected in vitro. Cur-Au NPs-PEG provided a hyperthermal microenvironment and generated reactive oxygen species upon PTT and STD, respectively, with representing synergism effects. Studies in vivo in a tumor-bearing animal also demonstrate the superiority of PTT and SDT in destroying melanoma tumor.


Assuntos
Curcumina , Nanopartículas , Fotoquimioterapia , Animais , Linhagem Celular Tumoral , Curcumina/farmacologia , Ouro , Camundongos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Fototerapia , Polietilenoglicóis
10.
Ultrason Sonochem ; 54: 274-280, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30712854

RESUMO

In this study, high-frequency ultrasound wave (1.8 MHz) at low intensity was applied to improve activated sludge settleability at high MLSS concentration. The effect of irradiation intensity, sonication mode, MLSS concentration and sample volume on the physical characteristics of sludge in a pilot scale settling column were investigated for optimizing the conditions. The obtained results showed that high-frequency ultrasound decreased the height of sludge (44%) and effluent turbidity (82.2%) and increased sludge settling velocity about 3 times at high biomass concentration. Irradiation intensity of 0.4 w/cm2 and sonication mode with interval times of 10 s showed the best results on the performance of the system at MLSS concentration of 8000 mg/L with a sample volume of 3 L.


Assuntos
Esgotos , Sonicação , Eliminação de Resíduos Líquidos/métodos , Biomassa
11.
J Colloid Interface Sci ; 513: 240-250, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29153718

RESUMO

Present report designed for monitoring and recovery of Azure-II (Az-II) using ultrasound assisted- dispersive-magnetic nanocomposites-solid-phase microextraction (UA-DMNSPME) based on Zn@Cu-Fe2O4-NCs-CNT sorbent. The full contribution of conventional factors like pH, sorbent amount, eluent volume and sonication time on response were studied and optimized using response surface methodology (RSM) combined with central composite design (CCD). According best figures of merits were achieved at following conditions: pH of 8.0; 5.0 mg sorbent and 5 min sonication which all accumulation Az-II was efficiently eluted by 180 µL of dimethylformamide which consequently permit achievement recovery of 99.8 ±â€¯1.1%. Under specified best conditions using 10.0 mL of sample at various conditions lead to detection limit (based on 3Sb/m), limit of quantification (10Sb/m) and the enrichment factor of 3.8, 12.6 ng mL-1 and 75.2, respectively. The while method has linear response over 30-4500 ng mL-1 of Az-II with acceptable correlation coefficient of R2 = 0.9996. Inter- and Intra-day precision expressed as relative standard deviation (n = 3) and the preconcentration factor were 1.1-4.0%, 1.4-5.0% and 55.6, respectively. Good recoveries (95.2-103.3%) with low relative standard deviations (1.1-5.0%) strongly support successful applicability of present method for Az-II preconcentration and determination.

12.
Ultrason Sonochem ; 41: 279-287, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29137753

RESUMO

This paper focuses on the finding best operational conditions using response surface methodology (RSM) for Rhodamine123 (R123) and Disulfine blue (DSB) dyes removal by ultrasound assisted adsorption onto Au-Fe3O4 nanoparticles loaded on activated carbon (Au-Fe3O4 NPs-AC). The influences of variables such as initial R123 (X1) and DSB concentration (X2), pH (X3), adsorbent mass (X4) and sonication time (X5) on their removal were investigated by small central composite design (CCD) under response surface methodology. The significant variables and the possible interactions among variables were investigated and estimated accordingly. The best conditions were set as: 4min, 4.0, 0.025g, 13.5 and 26.5mgL-1 for sonication time, pH, adsorbent weight, initial R123 and DSB concentration, respectively. At above conditions, the adsorption equilibrium and kinetic follow the Langmuir isotherm and pseudo-second-order kinetic model, respectively. The maximum monolayer capacity (Qmax) of 71.46 and 76.38mgg-1 for R123 and DSB show sufficiency of model for well presentation of experimental data.

13.
Photodiagnosis Photodyn Ther ; 19: 159-166, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28606724

RESUMO

Sonodynamic therapy (SDT) as a new non-invasive treatment developed from photodynamic (PDT), it can kill tumor cells specifically and selectively. Moreover, recently studies showed SDT has potential to treat solid tumor, leukemia and atherosclerosis, remove proliferative scars and kill pathogenic microorganism. As SDT has an extensive application prospect, SDT has attracted more and more research recently. This thesis aims to be an informative introduction on SDT. With the assistance of related literature from 2012 to 2016, we introduce the progress of SDT research in six aspects: the therapeutic mechanism of SDT, development of the sound sensitizer, exploration of the size and frequency of ultrasonic energy, application of SDT, comparison between SDT and PDT, and current situation and future of SDT.


Assuntos
Neoplasias/tratamento farmacológico , Terapia por Ultrassom/métodos , Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Aterosclerose/tratamento farmacológico , Células Dendríticas/efeitos dos fármacos , Humanos , Mediadores da Inflamação/metabolismo , Queloide/tratamento farmacológico , Leucemia/tratamento farmacológico , Macrófagos/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Nanopartículas , Porfirinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Xantonas/farmacologia
14.
J Environ Sci (China) ; 52: 276-283, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28254048

RESUMO

Batch mode experiments were conducted to study the removal of hexavalent chromium (Cr(VI)) from aqueous solutions using ultrasound-assisted aqueous solution ball milling. The results show that the reduction rate of Cr(VI) by ultrasound-assisted aqueous solution ball milling was significantly faster than that by ball milling or ultrasound treatment alone, and an initial Cr(VI) concentration of 166mg/L could be decreased to 0.35mg/L at 120min. The decisive factors, including initial concentration of Cr(VI), pH value, ultrasonic frequency and filling gas, were studied. It was found that the optimal ultrasonic frequency for ultrasound-assisted aqueous solution ball milling device was 20kHz, and the rate of Cr(VI) reduction as a function of filling gas followed the order: Ar>air>N2>O2. Samples were characterized by X-ray diffraction, fluorescence measurements, atomic absorption and the diphenylcarbazide colorimetric method. The Cr(VI) transformed into a precipitate that could be removed from the contaminated water, after which the water could be reused.


Assuntos
Cromo/química , Ultrassom/métodos , Poluentes Químicos da Água/química , Purificação da Água/métodos , Cromo/análise , Cinética , Poluentes Químicos da Água/análise
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