Low-intensity Ultrasound Research Articles

Structural and functional properties of self-assembled peanut protein nanoparticles prepared by ultrasonic treatment: Effects of ultrasound intensity and protein concentration

Peanut protein isolate (PPI) nanoparticles were prepared by self-assembly under the combined action of ultrasound (US) and protein concentration. The effects of ultrasound intensity (150–500 W) and protein concentration (1–12 %, w/v) on the structural and functional properties of PPI nanoparticles were investigated. Low-intensity US significantly increased the particle size of PPI, but high-intensity US decreased it. The largest PPI nanoparticles were obtained when 10 % PPI was subjected to low-intensity US treatment (200 W for 5 min). These nanoparticles possessed unique structural characteristics, such as the lowest absolute ζ-potential and the highest contents of exposed free sulfhydryl and disulfide bond, which may be responsible for their excellent heat-set gelling properties. The 12 % PPI treated with low- and high-intensity US had the highest emulsifying activity index and emulsifying stability index, respectively. The self-assembled PPI nanoparticles induced by US treatments at high protein concentrations have great potentials for application in the food industry.

Silent Death by Sound: C60 Fullerene Sonodynamic Treatment of Cancer Cells.

The acoustic pressure waves of ultrasound (US) not only penetrate biological tissues deeper than light, but they also generate light emission, termed sonoluminescence. This promoted the idea of its use as an alternative energy source for photosensitizer excitation. Pristine C60 fullerene (C60), an excellent photosensitizer, was explored in the frame of cancer sonodynamic therapy (SDT). For that purpose, we analyzed C60 effects on human cervix carcinoma HeLa cells in combination with a low-intensity US treatment. The time-dependent accumulation of C60 in HeLa cells reached its maximum at 24 h (800 ± 66 ng/106 cells). Half of extranuclear C60 is localized within mitochondria. The efficiency of the C60 nanostructure's sonoexcitation with 1 MHz US was tested with cell-based assays. A significant proapoptotic sonotoxic effect of C60 was found for HeLa cells. C60's ability to induce apoptosis of carcinoma cells after sonoexcitation with US provides a promising novel approach for cancer treatment.

Effects of Low-Intensity Ultrasound on Anammox Granular Sludge

Effects of Low-Intensity Ultrasound on Anammox Granular Sludge

Production enhancement of human adipose-derived mesenchymal stem cells by low-intensity ultrasound stimulation

Low-intensity ultrasound (LIUS) enhances the proliferation rate of various mammalian stem cells through mechanical stimulation. This study quantitively finds suitable LIUS stimulation parameters for increasing the proliferation rate of human adipose-derived mesenchymal stem cells (hAdMSCs) for mass production. Various stimulation conditions of LIUS were assessed based on the beam pattern of the ultrasonic transducer and the attenuation of the sound waves. Using optimal LIUS stimulation parameters for enhancing proliferation of hAdMSCs taken from bromodeoxyuridine (BrdU) incorporation assay, long-term culture of hAdMSCs was performed for 16 days. The resultant hAdMSCs were characterized for various biomarkers such as CD34−, CD45−, CD73+, CD95+, CD105+ and cytological staining and a cytokine array assay. LIUS stimulation parameters found for enhancing the hAdMSCs proliferation were the frequency of 5 MHz, an intensity of 300 mWcm−2, a duration of 10 min per day, and continuous waves with a 100% duty cycle. The LIUS stimulated hAdMSCs group showed a 3.25-fold increase in the cell number compared to the control group after 16 days of culture. By confirming the effects of quantitatively measured LIUS stimulation on the enhancement of hAdMSCs proliferation, this study may be a foundation for the applications of LIUS stimulation in the industrial-scale production of hAdMSCs.

Influence of Low-Intensity Ultrasound on ε-Polylysine Production: Intracellular ATP and Key Biosynthesis Enzymes during Streptomyces albulus Fermentation.

The effect of low-intensity sonication treatment on cell growth, ε-polylysine (ε-PL) yield and its biological mechanism were investigated, using a 3-L-jar fermenter coupled with an in situ ultrasonic slot with a Streptomyces albulus strain SAR 14-116. Under ultrasonic conditions (28 kHz, 0.37 W cm-2, 60 min), a high biomass of SAR 14-116 and concentration of ε-PL were realized (i.e., they increased by 14.92% and 28.45%, respectively) when compared with a control. Besides this, ultrasonication increased the mycelia viability and intracellular ATP as well as activities of key enzymes involved in the ε-PL biosynthesis pathway, resulting in an improvement in the production of ε-PL. Data on qRT-PCR revealed that ultrasonication also affected the gene expression of key enzymes in the ε-PL biosynthesis pathway, including ε-PL synthetase (PLS). These outcomes provided the basis for understanding the effects of ultrasound-assisted fermentation on the stimulation of metabolite production and fermentation procedure in a fermenter.

In vitro study about prevention of vascular reocclusion by low intensity ultrasonic irradiation.

For the treatment of acute ischemic stroke, the current standard of care is thrombolysis by the administration of intravenous (IV) recombinant tissue-type plasminogen activator (rt-PA). Although this approach is proven to be effective, reocclusion within 24 hours occurs in about 20% of patients who receive recanalization by rt-PA. In addition, the administration of anticoagulants within 24 hours after IV rt-PA increases the risk of intracranial hemorrhage; therefore, treatment with anticoagulants is contraindicated in this population. To address the need for an approach to sustain the effects of thrombolysis prevent blood vessel reocclusion without the use of anticoagulants, this study proposes a novel method using a low-intensity ultrasound (US) irradiation. An in vitro thrombus-growth model, in a latex rubber container was developed to study the effect of thrombus-growth suppression by US irradiation at 500 kHz in a 37°C water bath. The US acoustic intensity was set at or below 0.72 W/cm2, which is the maximum allowed for noninvasive acoustic irradiation. Low-intensity US irradiation of the thrombus-growth model resulted in a remarkable suppression of thrombus growth (100.22 ± 10.1 mg vs. 50.22 ± 5.3 mg, p < 0.0001), and the clot-growth inhibition depended logarithmically on acoustic intensity. Thrombus growth can be suppressed by low-intensity US irradiation, opening a new way to combat vascular reocclusion after rt-PA treatment of acute ischemic stroke.

Specific-Tuning Band Structure in Hetero-Semiconductor Nanorods to Match with Reduction of Oxygen Molecules for Low-Intensity Yet Highly Effective Sonodynamic/Hole Therapy of Tumors.

Sonosensitizers-assisted sonodynamic therapy (SDT) has been emerging as a promising treatment for cancers, and yet few specific regulations of band structure of sonosensitizers have been reported in relation to oxygen in tissues. Herein, by a gradient doping technique to modulate the band structure of hetero-semiconductor nanorods, it is found that the reduction potential of band-edge is very critical to reactive oxygen species (ROS) production under low-intensity ultrasound (US) irradiation and particularly, when aligned with the reduction of oxygen, ROS generation is found to be most significantly enhanced. Withal, US-generated oxidation holes are found to be effective in consuming overexpressed glutathione in tumor lesions, which amplifies cellular oxidative stress and finally induces tumor cell death. Moreover, the intrinsic fluorescence property of semiconductors provides imaging capability to illumine tumor area and guide the SDT process. This study demonstrates that the reduction potential state of sonosensitizers is of crucial importance in ROS generation and the proposed reduction potential-tailored hetero-semiconductor nanorods materialize low-intensity US irradiation yet highly effective SDT and synergetic hole therapy of tumors with imaging guidance and reduced radiation injury.

Insights into the enhanced effect of Low-Intensity Ultrasound on anammox granular sludge by relieving the embolism

Like the lethal cardiovascular embolism in humans, the serious blockage of the mass transfer channel can inactivate anammox granular sludge (AnGS). Also like the therapeutic thrombolysis in humans, the remediatory dredging of the mass transfer channel can sustain the function of AnGS. In this study, the ultrasound was thus explored to remediate the embolism of AnGS. It turned out that Low-Intensity Ultrasound (LIU) with an energy density of 5.6 kJ/(g-VSS·cm2) was optimal to achieve an obvious increase in specific anammox activity of AnGS by 34.8% to 420.3 mg-N/(g-VSS·d). The improved mass transfer of AnGS and cell membrane permeability of anammox bacteria (AnAOB) was revealed to mainly contribute to the enhanced activity. After treatment with LIU under optimal conditions, the mass transfer efficiency of AnGS was improved by 26.9% with enhanced permeability, and the proportions of pores larger than 50 μm in the surface layer of AnGS increased by 13.7% evidenced by the micro-CT observation. Correspondingly, the permeability of AnAOB was increased by inducing instantaneous pores on the cell membrane, thus stimulating the metabolism by 6.9%. Further analysis demonstrated that LIU was capable of breaking the hydrogen bonds of protein in the EPS and loosening its spatial structure, which would benefit the partially exfoliation and dissolution of EPS and resulted in enlarging and dredging pores, thus relieving the embolism of AnGS. Consequently, the results of this study could deepen the understanding of granules treated by ultrasound and also provide a promising technique for raising the ceiling of nitrogen removal performance by AnGS.

Low-intensity ultrasound promotes uterine involution after cesarean section: the first multicenter, randomized, controlled clinical trial

Objective To evaluate the clinical efficacy and safety of low-intensity ultrasound (LIUS) in promoting uterine involution and relieving postpartum pain. Methods The randomized controlled clinical trial in this study was conducted at five centers in three regions across China from June 2014 to December 2014. A total of 498 subjects were randomly divided into two groups. The LIUS group received ultrasound treatment, and the control group received sham ultrasound treatment. The fundal height and visual analogue scale (VAS) scores of the subjects following cesarean section were recorded separately before and after five treatments. The incidence of adverse events was recorded, while the records on lochia duration were obtained by telephone follow-up. The Full Analysis Set (FAS) comprised all subjects randomized who received at least one treatment. The Per-Protocol Set (PPS) comprised all patients who did not seriously violate the study protocol and had good compliance with complete report forms. Efficacy analyses were performed based on the FAS and PPS. All safety analyses were performed based on the safety set (SS), which included all patients who received at least one treatment. Results In the analysis of PPS and FAS, the LIUS group performed better than the control group in reducing the fundal height, shortening the duration of lochia, and relieving postpartum pain, with a significant difference between the two groups (p < 0.0001). In the SS analysis, there were no treatment-related adverse events observed in either group. Conclusions The LIUS therapy is safe and effective, which contributes to uterine involution and the alleviation of postpartum pain.

Biophysical and Biomechanical Effect of Low Intensity US Treatments on Pancreatic Adenocarcinoma 3D Cultures

Current developments in medical technology have focused on therapeutic treatments that selectively and effectively address specific pathological areas, minimizing side effects on healthy tissues. In this regard, many procedures have been developed to provide non-invasive therapy, for example therapeutic ultrasound (US). In the medical field, in particular in cancer research, it has been observed how ultrasounds can cause cell death and inhibit cell proliferation of cancer cells, while preserving healthy ones with almost negligible side effects. Various studies have shown that low intensity pulse ultrasound (LIPUS) and low intensity continuous ultrasound (LICUS) regulate the proliferation, cell differentiation and cavitation phenomena. Nowadays, there are poorly known aspects of low intensity US treatment, in terms of biophysical and biomechanical effects on target cells. The aim of this study is to set up an innovative apparatus for US treatment of pancreatic ductal adenocarcinoma (PDAC) cells, monitoring parameters such as acoustic intensity, acoustic pressure, stimulation frequency and treatment protocol. To this purpose, we have developed a custom-made set up for the US stimulation at 1.2 and 3 MHz of tridimensional (3D) cultures of PDAC cells (PANC-1, Mia Paca-2 and BxPc3 cells). Images of the 3D cultures were acquired, and the Calcein/PI assay was applied to detect US-induced cell death. Overall, the setup we have presented paves the way to an innovative protocol for tumor treatment. The system can be used either alone or in combination with small molecules or recombinant antibodies in order to propose a novel combined therapeutic approach.

Accelerating anammox nitrogen removal in low intensity ultrasound-assisted ASBBR: Performance optimization, EPS characterization and microbial community analysis

Efficient enrichment of slow-growing anammox species is essential for rapid start-up and stable operation of high-rate anammox reactors. Herein, a low intensity ultrasound (LIU) was introduced into anaerobic sequencing batch biofilm reactors (ASBBRs) to enhance anammox nitrogen removal from nitrogen-rich wastewater. Operation results demonstrated that the maximum total nitrogen (TN) removal efficiency of 91.5% were achieved under the optimal ultrasonic parameters (32.7 °C water temperature, 0.18 W/cm2 ultrasonic intensity and 25.7 min ultrasonication time). Moreover, significant increases of extracellular polymeric substances (EPS) components and contents were observed via the ultrasonication stimulation. A close correlation between nitrogen removal and shifts in transformation and intensity of spectrum peaks was also verified by three-dimensional excitation-emission matrix spectroscopy (3D-EEM) analysis. High-throughput sequencing revealed that the relative abundance of Candidatus Kuenenia as the key anammox consortium significantly increased after applying optimal ultrasonication condition. Furthermore, enhancement mechanisms and future prospect of the LIU-assisted anammox process was elucidated and discussed. This research provides a viable and promising acceleration strategy for anammox-based process in practice.

Therapeutic Low-Intensity Ultrasound for Peripheral Nerve Regeneration - A Schwann Cell Perspective.

Peripheral nerve injuries are common conditions that can arise from trauma (e.g., compression, severance) and can lead to neuropathic pain as well as motor and sensory deficits. Although much knowledge exists on the mechanisms of injury and nerve regeneration, treatments that ensure functional recovery following peripheral nerve injury are limited. Schwann cells, the supporting glial cells in peripheral nerves, orchestrate the response to nerve injury, by converting to a “repair” phenotype. However, nerve regeneration is often suboptimal in humans as the repair Schwann cells do not sustain their repair phenotype long enough to support the prolonged regeneration times required for successful nerve regrowth. Thus, numerous strategies are currently focused on promoting and extending the Schwann cells repair phenotype. Low-intensity ultrasound (LIU) is a non-destructive therapeutic approach which has been shown to facilitate peripheral nerve regeneration following nerve injury in rodents. Still, clinical trials in humans are scarce and limited to small population sizes. The benefit of LIU on nerve regeneration could possibly be mediated through the repair Schwann cells. In this review, we discuss the known and possible molecular mechanisms activated in response to LIU in repair Schwann cells to draw support and attention to LIU as a compelling regenerative treatment for peripheral nerve injury.

Enhancing Enzyme Activity Via Low-Intensity Ultrasound for Protein Extraction from Excess Sludge

Enhancing Enzyme Activity Via Low-Intensity Ultrasound for Protein Extraction from Excess Sludge

Sonodynamic Effects of a Novel Ether-Group Modified Porphyrin Derivative Combined With Pulsed Low-Intensity Ultrasound on PC-9 Cells.

Sonodynamic therapy (SDT) is a developing modality for cancer treatment based on the synergistic effect of ultrasound and chemical compounds which are known as sonosensitizers. The development of more efficient sonosensitizers has become an urgent issue in this field. In this study, a novel porphyrin derivative (BBTPP) mediated SDT was evaluated on PC-9 cells. Pulsed low-intensity ultrasound (PLIU) was used for its little thermal and mechanical damage. The accumulation of drugs in cells was evaluated through porphyrin fluorescence, and the cytotoxicity of BBTPP was evaluated using a cell counting kit-8 assay. The sonodynamic effect was investigated by Hoechst 33342/PI and Annexin V-FITC/PI double staining, which showed an apoptotic rate of 18.87% in the BBTPP-SDT group, as compared with 1.71%, 1.4%, 1.57%, 3.61%, 11.18% in the control, BBTPP, hematoporphyrin monomethyl ether (HMME), ultrasound, and HMME-SDT groups, respectively. The sono-toxic effect of BBTPP was significantly superior to HMME. Our results showed that BBTPP-SDT resulted in much higher intracellular reactive oxygen species (ROS) and lipid peroxidation levels which were evaluated by 2′,7′-dichlorodihydrofluorescein diacetate (H2DCFDA) and Liperfluo assay, respectively. The expressions of Bax, Bcl-2, caspase-9, caspase-8, and cleaved caspase-3 proteins were evaluated to investigate the apoptotic mechanism of BBTPP-SDT. The results of this study showed that the combination of BBTPP and PLIU induced the generation of ROS, resulting in lipid peroxidation, and activated both the extrinsic and intrinsic apoptotic pathways of PC-9 cells. Our results also suggested that the ether group introduced in the side chain of porphyrin could enhance the sono-toxicity of porphyrin-based sensitizers under the sonication of PLIU. These results supported the possibility of BBTPP as a promising sonosensitizer, and an appropriate side chain could enhance the sono-sensitivity of porphyrins.

Low-intensity ultrasound (LIUS) differentially modulates mitochondrial reactive oxygen species (mtROS) generation by three different chemicals in PC12 cells

We have previously shown that low-intensity ultrasound (LIUS) can modulate mitochondrial complex I activity and the generation of mitochondrial reactive oxygen species (mtROS) in PC12 cells. This study investigated the mechanism of LIUS by comparing its effect on mitochondrial dysfunction by three different pathways. LIUS was shown to reverse the effects of rotenone, a Q-site blocker, on the complex I inhibition, mtROS generation, and drop of mitochondrial membrane potential (Δψm). In contrast, common antioxidants, N-acetyl cysteine (NAC), and uric acid (UA) blocked rotenone-induced mtROS generation and Δψm drop without recovering the complex I activity, which suggested that Δψm drop is correlated with mtROS generation rather than complex I inhibition itself. Ionomycin, an ionophore for Ca2+, and L-buthionine-S,R-sulfoximine (BSO), an inhibitor of glutathione (GSH) biosynthesis, induced mtROS generation and Δψm drop without inhibiting complex I activity via different mechanisms. LIUS showed no effect on ionomycin-induced Δψm drop but showed partial inhibition on the other effects of ionomycin and BSO. These results suggest that LIUS might have redundant mechanisms but acted mainly on the complex I activity thereby modulating mtROS and Δψm levels. LIUS appeared to act on the Q-module of complex I because it showed no inhibitory effect on Zn2+, an inhibitor of the proton transporting P-module of complex I. Interestingly, pretreatment of LIUS for up to an hour in advance blocked the rotenone effect as efficiently as the co-treatment. Further studies are needed to reveal the exact mechanism of LIUS to inhibit complex I activity.

Intrinsic nucleus-targeted ultra-small metal\u2013organic framework for the type I sonodynamic treatment of orthotopic pancreatic carcinoma

BackgroundSonodynamic therapy (SDT) strategies exhibit a high tissue penetration depth and can achieve therapeutic efficacy by facilitating the intertumoral release of reactive oxygen species (ROS) with a short lifespan and limited diffusion capabilities. The majority of SDT systems developed to date are of the highly O2-dependent type II variety, limiting their therapeutic utility in pancreatic cancer and other hypoxic solid tumor types.ResultsHerein, a nucleus-targeted ultra-small Ti-tetrakis(4-carboxyphenyl)porphyrin (TCPP) metal–organic framework (MOF) platform was synthesized and shown to be an effective mediator of SDT. This MOF was capable of generating large quantities of ROS in an oxygen-independent manner in response to low-intensity ultrasound (US) irradiation (0.5 W cm−2), thereby facilitating both type I and type II SDT. This approach thus holds great promise for the treatment of highly hypoxic orthotopic pancreatic carcinoma solid tumors. This Ti-TCPP MOF was able to induce in vitro cellular apoptosis by directly destroying DNA and inducing S phase cell cycle arrest following US irradiation. The prolonged circulation, high intratumoral accumulation, and nucleus-targeting attributes of these MOF preparations significantly also served to significantly inhibit orthotopic pancreatic tumor growth and prolong the survival of tumor-bearing mice following Ti-TCPP + US treatment. Moreover, this Ti-TCPP MOF was almost completely cleared from mice within 7 days of treatment, and no apparent treatment-associated toxicity was observed.ConclusionThe nucleus-targeted ultra-small Ti-TCPP MOF developed herein represents an effective approach to the enhanced SDT treatment of tumors in response to low-intensity US irradiation.Graphic abstract

Chemotherapy Augmentation Using Low-Intensity Ultrasound Combined with Microbubbles with Different Mechanical Indexes in a Pancreatic Cancer Model

The aim of the study was to explore the optimal mechanical indexes (MIs) for low-intensity ultrasound (LIUS) combined with microbubbles to enhance tumor blood perfusion and improve drug concentration in pancreatic cancer-bearing nude mice. Fifty-four nude mice bearing bilateral pancreatic tumors on the hind legs were randomly divided into three groups (the MI was set at 0.3, 0.7 and 1.1 in groups A, B and C, respectively). Five nude mice in each group were intravenously injected with the fluorescent dye DiR iodide (DiIC18(7),1,1′-dioctadecyl-3,3,3′,3′-tetramethylindotricarbocyanine iodide); for each mouse, one tumor was treated with LIUS combined with microbubbles, and the contralateral tumor was exposed to sham ultrasound. In vivo fluorescence imaging was performed to detect the enrichment of intratumoral DiR iodide. Twelve mice in each group were intravenously injected with doxorubicin (DOX) and underwent ultrasound therapy as described above. Tumor blood perfusion changes were quantitatively evaluated with pre- and post-treatment contrast-enhanced ultrasound (CEUS, MI = 0.08). One hour after the post-treatment CEUS, nude mice were sacrificed to determine the DOX concentration in tumor tissue; one mouse in each group was sacrificed after ultrasound treatment for tumor hematoxylin–eosin staining examination. CEUS quantitative analysis and in vivo fluorescence images confirmed that LIUS at MI = 0.3 combined with microbubbles was able to enhance tumor blood flow and increase regional fluorescence dye DiR iodide concentration. The DOX concentration on the therapeutic side was significantly higher than that on the control side after ultrasound-stimulated (MI = 0.3) microbubble cavitation (USMC) treatment (1.45 ± 0.53 μg/g vs. 1.07 ± 0.46 μg/g, t = –5.163, p = 0.001). However, in groups B and C, there were no significant differences in DOX concentration between the therapeutic and control sides (Z = –0.297, –0.357, p = 0.766, 0.721). No hemorrhage or other tissue damage was observed in hematoxylin–eosin-stained tumor specimens of both sides in all groups. LIUS at MI = 0.3 combined with microbubbles was able to enhance tumor blood perfusion and improve local drug concentration in nude mice bearing pancreatic cancer.

Sonodynamic therapy and common head and neck cancers: in vitro and in vivo studies.

Carcinogenesis is a complex multi-stage process associated with abnormal oncogenic signals in various signaling pathways. HNSCC (Head and neck squamous cell carcinoma) includes the majority of head and neck cancers (HNC). Also, HNSCC indicates a tumors heterogeneous group that derives from the squamous epithelium of the oropharynx, hypopharynx, oral cavity, and larynx. The main cancer management approach contains chemotherapy, radiation, and surgery separately or in combination. Each therapeutic approach has a limitation that influences cancer therapy procedures. Different treatment manners, stimuli-responsive therapeutic methods can improve on-target responses and reduce side effects. Sonodynamic therapy (ST) shows promising potential as an alternative treatment for cancer in the last few years. There is a hypothesis that shows ST using sonosenitizer in combination with low-intensity ultrasound (LIUS) could be useful in all kinds of cancer without focusing on specific target proteins, molecules, and/or genes. This review study discussed the application of ST for the treatment, ST mechanisms, and also, advances in the treatment of HNCs approaches in the recent decades.

Induction Therapy of Retinoic Acid with a Temozolomide-Loaded Gold Nanoparticle-Associated Ultrasound Effect on Glioblastoma Cancer Stem-Like Colonies.

Glioblastoma multiforme (GBM) is the most aggressive glioma. The treatment response is always low, and the condition is typically rapidly fatal. The undifferentiated and self-renewal characteristics of cancer stem cells (CSCs) have been reported, and their potential contribution may cause tumor initiation, recurrence, metastasis, and therapeutic resistance. In particular, glioblastoma stem-like cells exhibit highly invasive properties and drug resistance, serving as a model for the development of novel therapeutic strategies. Induction therapy provides an alternative therapeutic strategy to eliminate the stem cell properties of CSCs and enhance therapeutic sensitivity. The differentiated cells may lose their self-renewal ability, downregulate stem cell-related genes and drug resistance genes, and enhance anticancer drug sensitivity. Therefore, the purpose of this study is to establish a niche for glioblastoma stem-like cell selection as a platform and facilitate the assessment of differentiation therapy on GBM cancer stem-like colonies by retinoic acid (RA) with temozolomide (TMZ)-loaded gold nanoparticles (GNPs) associated with low-intensity ultrasound (LIUS). Herein, a hyaluronic acid-based material system was used to isolate GBM cancer stem-like colonies. Colony formation, size determination, stem cell-related marker expression, and GBM cancer stem-like cell marker expression with the culture period were identified. The effect of TMZ on GBM stem-like colonies on HA-based material systems was also determined, and the results revealed that drug resistance was highly enhanced in GBM colonies compared with that in the control cell population. In addition, GBM colonies also exhibited a significant increase in breast cancer resistance protein expression, which is consistent with the drug resistance effect. Furthermore, several factors, including LIUS, RA, and GNPs, were used to determine the possibility of induction therapy. RA with TMZ-loaded GNP-associated LIUS stimulation exhibited a significant and synergistic effect on the differentiation effect and drug sensitivity enhancement. The GBM cancer stem-like colony system presents an opportunity for the development of new therapeutic strategies, and this study provides an alternative differentiation therapy for malignant tumors.

Analysis of the simultaneous measurement of acoustic phase velocity and stress-strain relationship in beef: An approach to Young's modulus

Ultrasound is a tool that has two fields of study and application. On the one hand, the characterization of materials by means of low intensity ultrasound (LIU) and on the other, the modification of materials by applying high intensity ultrasound (HIU). In the last decades ultrasound has been applied in the food industry. The LIU is primarily applied as an evaluation system to determine the quality of food. In the meat industry, medical ultrasound has been used to check the status of meat postmortem. In some cases, also, acoustic properties such as acoustic phase velocity (APV) and attenuation are determined, which is a way of predicting the texture of the meat, where the nature and strain of the samples can modify the results of the velocity values acoustic phase. However, there is no precise information on how the strain of the sample could affect the measurements. The aim of this research was to determine the effect of sample strain (%), muscle (Longissimus thoracis, LT; Longissimus lumborum, LL and Psoas major, PM) and high intensity ultrasound (HIU, 0 or 90 W/cm2) application on LIU-APV [c, m/s] measures. The factors mentioned above significantly (P < 0.05) affected LIU-APV with no interaction effect. APV is related to meat texture, muscles considered as tender resulted in lower phase velocity. However, a better relation was observed with characteristic acoustic impedance (Z) and stress. Additionally, HIU pretreatment resulted in LIU-APV decrease of ≅ 41.6 m/s. Finally, sample strain affected LIU measures with an inverse trend, the lowest LIU-APV values were found at 40% sample deformation with a 10% of APV decrease ≅ 149 m/s. LIU contact conditions should be standardized to a level where the air in the sample and the ultrasonic sensor coupling can move without causing irreversible damage to the meat sample, ultrasonic gel is commonly used, in order to couple the tissue and sensor impedances.