Search Results (189)

The unique properties of phthalocyanines (Pcs), such as strong absorption, high photostability, effective singlet oxygen generation, low toxicity and biocompatibility, versatile chemical modifications, broad spectrum of antimicrobial activity, and synergistic effects with other treatment modalities, make them a preferred superior sensitizer in the field of antimicrobial photodynamic therapy. The photodynamic and sonodynamic activity of 3-(3-(diethylamino)phenoxy)propanoxy substituted silicon(IV) Pc were evaluated against bacteria and cancer cells. Stability and singlet oxygen generation upon light irradiation and ultrasound (1 MHz, 3 W) were assessed with 1,3-diphenylisobenzofuran. The phthalocyanine revealed high photostability in DMF and DMSO, although the singlet oxygen yields under light irradiation were low. On the other hand, the phthalocyanine revealed excellent sonostability and caused a high rate of DPBF degradation upon excitation by ultrasounds at 1 MHz. The silicon phthalocyanine presented significant bacterial reduction growth, up to 5 log against MRSA and S. epidermidis upon light excitation, whereas the sonodynamic effect was negligible. The phthalocyanine revealed high activity in both photodynamic and sonodynamic manner toward hypopharyngeal tumor (FaDu, 95% and 42% reduction, respectively) and squamous cell carcinoma (SCC-25, 96% and 62% reduction, respectively). The sensitizer showed ca. 30% aldehyde dehydrogenase inhibition in various concentrations and up to 85% platelet-activating factor acetylhydrolase for 0.25 μM, while protease-activated protein C was stimulated up to 66% for 0.75 μM. Full article

Objectives: The objectives are to evaluate the influence of different maternal characteristics on ultrasound image quality and operator satisfaction, and to assess, preliminarily, a rating scale to stratify the difficulty level of ultrasound examination in early gestation. Methods: A multicentric observational study of ultrasound scans was carried out on singleton pregnant women undergoing routine gestational ultrasound at 11–14 weeks and 19–21 weeks of gestation at two Prenatal Care Centers in the Apulia region (Southern Italy). Inclusion criteria included the presence of one or more limiting features, i.e., obesity, retroverted uterus, myomas, previous abdominal surgery, and limited echo-absorption. Each woman was given an overall pre-echographic limiting score from 0 to 9. The outcome measure was the operator’s satisfaction with the examination, scored on a Likert scale. Nested linear regression models (raw, semi- and fully adjusted) were built for each of the two trimesters on the pre-ecographic limiting score (0–9 points) as dependent variables, with the operator’s satisfaction as the regressor. Results: The whole sample included 445 pregnant women. The two-center samples did not show statistically different baseline features. The operator’s satisfaction with the sonographic examination was significantly (and inversely) related to the pre-echographic limiting score, regardless of the mother’s age, the operator performing the ultrasound, the Hospital Center where the ultrasound examination was performed, and the duration of the sonographic examination. Conclusions: A number of maternal conditions need to be monitored for good ultrasound performance; using a specific rating scale to stratify the level of difficulty of the ultrasound examination at early gestation could represent a potentially useful tool, although it requires further validation. Full article

Medical phantoms are essential to imaging calibration, clinician training, and the validation of therapeutic procedures. However, most ultrasound phantoms prioritize acoustic realism while neglecting the viscoelastic and anisotropic properties of fibrous soft tissues. This gap limits their effectiveness in modeling realistic biomechanical behavior, especially in wave-based diagnostics and therapeutic ultrasound. Current materials like gelatine and agarose fall short in reproducing the complex interplay between the solid and fluid components found in biological tissues. To address this, we developed a soft, anisotropic composite whose dynamic mechanical properties resemble fibrous biological tissues such as skin and skeletal muscle. This material enables wave propagation and vibration studies in controllably anisotropic media, which are rare and highly valuable. We demonstrate the tunability of damping and stiffness aligned with fiber orientation, providing a versatile platform for modeling soft-tissue dynamics and validating biomechanical simulations. The phantoms achieved Young’s moduli of 7.16–11.04 MPa for skin and 0.494–1.743 MPa for muscles, shear wave speeds of 1.51–5.93 m/s, longitudinal wave speeds of 1086–1127 m/s, and sound absorption coefficients of 0.13–0.76 dB/cm/MHz, with storage, loss, and complex moduli reaching 1.035–6.652 kPa, 0.1831–0.8546 kPa, and 2.138–10.82 kPa. These values reveal anisotropic response patterns analogous to native tissues. This novel natural fibrous composite system affords sustainable, low-cost ultrasound phantoms that support both mechanical fidelity and acoustic realism. Our approach offers a route to next-gen tissue-mimicking phantoms for elastography, wave propagation studies, and dynamic calibration across diverse clinical and research applications. Full article

Striae distensae (SD), or stretch marks, are a common aesthetic concern with limited effective treatment options. This prospective, single-center, open-label study aimed to evaluate the efficacy and safety of 1470 nm non-ablative laser therapy in improving skin texture and reducing SD dimensions. Twenty healthy female volunteers (aged 19–56) with SD of varying stages underwent three laser sessions at three-week intervals. Treatments were delivered using energy densities of 28–35 mJ per point with spot spacing of 0.8–1.2 mm, uniformly delivered over the affected SD lesions. Assessments were performed at baseline, Day 14, Day 35, Day 56–70, and Day 118–132. SD depth and width were measured using high-frequency ultrasound; aesthetic improvement was assessed using the Global Aesthetic Improvement Scale (GAIS), alongside clinical and photographic evaluations. A statistically significant, progressive reduction in SD size was observed: mean depth decreased from 0.34 mm (SD = 0.16) to 0.18 mm (SD = 0.15), and width decreased from 6.58 mm (SD = 2.65) to 4.40 mm (SD = 2.52) by Day 118–132 (p < 0.01 for both). Most participants reported improvement on GAIS at each follow-up. No severe adverse events occurred; only mild, transient erythema and edema were noted. In conclusion, 1470 nm non-ablative laser therapy showed significant efficacy and a favorable safety profile in SD treatment, offering a promising non-invasive option based on fractional thermal stimulation and selective dermal absorption. Full article

Photoacoustic imaging (PAI) merges the high spatial resolution of optical methods with the deep tissue penetration provided by ultrasound, making it a valuable tool in biomedical imaging. In recent years, a diverse array of photoacoustic contrast agents, spanning both organic and inorganic materials, has been developed. Among them, upconversion nanoparticles (UCNPs) stand out as promising candidates due to their unique optical features, tunable absorption in the near-infrared I (NIR-I, 750–1350 nm) region, and strong potential for both imaging and treatment-related uses. This review discusses the growing significance of UCNPs in the field of PAI, focusing on their structural characteristics, strengths, and existing challenges. Then, we talk about an up-to-date account of the current literature on the use of UCNPs as contrast agents for PAI. Lastly, we discuss the challenges and perspectives of UCNPs as a contrast agent for PAI in preclinical research and clinical diagnosis. Full article

Flavonoids, widely present in Artemisia argyi (AA), offer potential health benefits but are limited in food applications because of their bitter taste, inadequate absorption, and stability. Casein micelles encapsulation can enhance the flavonoid absorption, stability, and bioactivity. In this study, Artemisia argyi flavonoids (AAFs) were extracted using ultrasound-assisted extraction (UAE) to optimize the process. The glycosylation reaction between casein (CN) micelles and oat β-glucan (OBG) was employed to improve AAF’s emulsifying stability, sustained release during digestion, and cellular uptake. The maximum glycosylation degree of 32.33% was achieved at a CN-to-OBG ratio of 1:2, 120 min browning time, and 95 °C temperature. This glycosylated delivery system enhanced the emulsifying properties of the AAFs, digestive sustained release, and cellular uptake, showing potential as a cross-linking material for fat-soluble substances and medicines. Full article

The need to use environmentally friendly and cost-effective methods to remove heavy metals from wastewater is a permanent concern worldwide. Eggshells have been indicated as a worthy biosorbent for the adsorption of heavy metals due to their bioavailability and composition. In the present study, the absorption capacity of untreated chicken (CEs) and quail (QEs) eggshells for the removal of Pb and Zn ions from aqueous solutions was evaluated at room temperature and 40 °C, using four types of agitation systems: classical and orbital agitation and ultrasonic and microwave-assisted activation. The monitoring of aqueous solutions was performed by electrochemical and spectro-analytical (AAS) procedures before and after the adsorption process. FTIR and RAMAN spectroscopy, SEM-EDAX microanalysis, and X-ray diffraction were used to investigate the characteristics of eggshell samples post-exposure to Pb²⁺ or Zn²⁺. For any type of agitation and temperature, the CEs were able to induce more than 65% removal efficiency for lead and over 80% in the case of zinc. Concerning the Zn removal efficiency of QEs, notable results were recorded when microwaves were applied (>90%) and at 40 °C for orbital shaking and ultrasound (>80%). The results of the present study may offer new and valuable information for the optimal removal of Pb²⁺ and Zn²⁺ using eggshells, thus contributing to the sustainable management of waste through the recycling of this type of biomaterial. Full article

The propagation of high-frequency ultrasound waves will generate both physical and chemical effects as they propagate through a liquid medium, such as acoustic streaming, an acoustic fountain, and atomization. These phenomena are believed to be the main factors that contribute to the enhancement of mass transfer in the gas–liquid carbon dioxide (CO₂) absorption system. Computational Fluid Dynamic (CFD) simulation is one of the powerful tools that can be used to model the complex hydrodynamic behavior induced by the propagation of ultrasound waves in the liquid medium. In this study, the ultrasonic irradiation forces were simulated via the momentum source term method using commercial CFD software (ANSYS Fluent V19.1). In addition, a parametric study was conducted to investigate the influences of absorber height and ultrasonic power on the hydrodynamic mixing performance. The simulation results indicated that enhanced mixing and a higher intensification factor were achieved with increased fountain flow velocity, particularly at the lowest absorber height and highest ultrasonic power. Conversely, the energy efficiency was improved with the increase of absorber height and decrease of ultrasonic power. To determine the optimal combination of absorber height and ultrasonic power, this trade-off between the energy efficiency and intensification in the ultrasonic-assisted absorption system (UAAS) is a crucial consideration during process scale-up. Full article

Photoacoustic imaging is an advanced biomedical imaging technique that has been widely developed and applied in diverse biomedical studies. By generating optical-absorption-based signals with ultrasound resolution, it enables in vivo visualization of molecular functional information in biological tissues. Extensive research has been conducted to develop the multispectral light sources required for functional photoacoustic imaging. Among the various approaches, multispectral light sources generated using stimulated Raman scattering have shown considerable promise, particularly in photoacoustic microscopy, where achieving multispectral illumination remains challenging. This review summarizes photoacoustic imaging systems that employ stimulated Raman scattering for multispectral light sources and delves into their configurations and applications in the functional analyses of biological tissues. In addition, the review discusses the future directions of multispectral light sources by comparing different technologies based on key factors such as wavelength tunability, repetition rate, and power, which critically affect the accuracy and quality of multispectral photoacoustic imaging. Full article

The banana inflorescence (BI) is a rich source of antioxidants and dietary fiber, making it a valuable by-product of banana harvesting. This study aimed to maximize the ultrasound-assisted extraction (UAE) of antioxidant compounds from BI and analyze the residue’s composition and functional properties. The Box–Behnken Design was applied to test different ultrasound powers, temperatures, and sample-to-solvent ratios on the total phenolic content (TPC) and total flavonoid content (TFC). The UAE conducted at 350 W, 55 °C, 1:30 (g/mL) ratio for 30 min resulted in the highest TPC (1637.12 mg/100 g) and TFC (22.97 mg/100 g). Isovanillin, caffeine, naringin, sinapaldehyde, nicotinic acid, quinic acid, malic acid, and fumaric acids were reported for the first time for BI. The extract obtained by UAE showed a higher content of these compounds and higher antioxidant activity than that obtained through conventional extraction (orbital shaking). The residue obtained after UAE presented dietary fiber as the main component (71.91 g/100 g) and a higher oil absorption index (5.78 g/g) than untreated BI. Therefore, BI is a source of bioactive compounds, and both the extract and residue can be used in the pharmaceutical, food, and cosmetic industries, enabling the productive sector to move closer to the circular economy. Full article

This study investigated the effects of ultrasound treatment on the physicochemical properties and thermal stability of durian starch. Durian starch samples were subjected to ultrasound at 20 kHz and 500 W for 2 min. The treatment significantly increased the starch extraction yield by 14.55% compared to untreated starch. Scanning electron microscopy analysis revealed that ultrasound treatment induced physical modifications in the starch granules, including the formation of cracks and pores, which likely contributed to the enhanced extraction efficiency and influenced the starch’s gelation behavior. Thermal analysis, including differential scanning calorimetry and thermogravimetric analysis, demonstrated that ultrasound-treated starch exhibited higher thermal stability compared to native starch. The thermogravimetric analysis results indicated a lower weight loss at high temperatures (70.39% for ultrasound-treated starch versus 79.55% for native starch at 596 °C). The heat flow during thermal decomposition was reduced in ultrasound-treated starch, suggesting that the treatment induced structural modifications that strengthened the gel matrix and improved resistance to thermal degradation. Additionally, ultrasound treatment enhanced the functional properties of durian starch, including swelling power, solubility, and water absorption capacity, which are critical for hydrogel formation and food-grade gel applications. These findings highlight the potential of ultrasound-treated durian starch for advanced applications in food hydrogels, biodegradable films, and gel-based delivery systems. Full article

Submerged fermentation offers a controlled environment for coffee processing, ensuring a consistent temperature and aerobic–anaerobic conditions, making it a superior alternative to solid-state fermentation. This study aimed to optimize submerged fermentation conditions for green coffee beans to maximize total phenolic content (TPC) and antioxidant activity, such as ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), DPPH (2,2-Diphenyl-1-picrylhydrazyl), and FRAP (the ferric reducing antioxidant power). Additionally, pH, yeast, and lactic acid bacteria counts were monitored. Fermentation was conducted with selective microbial starters, a varying temperature (25–35 °C), incubation time (3–9 days), and coffee weight (5–10 g) using a Box–Behnken design. To enhance bioactive compound infusion, fresh coffee cherries underwent ultrasonic treatment, increasing their porosity and water-holding capacity. Vacuum impregnation was then used to infuse fermented green coffee bean extract into the cherries. The lowest pH coincided with peak yeast growth, while the coffee weight significantly influenced all responses. The incubation time affected most parameters except DPPH activity, and the temperature impacted only ABTS and DPPH activities. Optimal conditions (35 °C; 7.21 days; 10 g) yielded a TPC of 480.25 µmol GAE/100 g with ABTS, DPPH, and FRAP activities of 725.71, 164.15 and 443.60 µmol TE/g, respectively. Ultrasound-treated coffee cherries exhibited increased porosity and absorption capacity, facilitating enhanced bioactive compound infusion during 3 h of vacuum impregnation. In conclusion, submerged fermentation effectively improves bioactive compound production, while ultrasound treatment and vacuum impregnation present promising methods for developing high-value dehydrated coffee cherry products. Full article

In this study, we have developed an optical fiber ultrasound emitter based on the thermal cavitation effect. A tube filled with a highly absorptive liquid is sealed at the end of an optical fiber pigtail. A continuous-wave laser is transmitted through the fiber, heating the highly absorptive copper salt solution near the fiber end face to its spinodal limit. Using a single-mode fiber, we achieved ultrasound pulses with an amplitude of 330 kPa and a repetition rate of 4 kHz in the frequency range of 5–17 MHz, and a bandwidth of 12 MHz was obtained by using a low laser heating power of 52 mW at a wavelength of 974 nm. This optical fiber ultrasound emitter features a simple fabrication process, low cost, and low optical power consumption. Its flexible design allows for easy integration into medical devices with small dimensions and makes it suitable for non-destructive testing in confined spaces. Full article

Background: Rutin is a natural flavonoid extracted primarily from plants with anti-inflammatory and antioxidant properties, and it is highly valuable in the cosmetics industry. However, the poor transdermal permeability of rutin limits its application via transdermal administration. Previous studies have predominantly focused on chemical methods for enhancing penetration. This study investigated the potential of ultrasound as a physical method by which to augment the transdermal absorption and anti-inflammatory effects of rutin. Method: Through in vitro diffusion experiments, we analyzed the effects of the ultrasonic frequency and intensity on percutaneous absorption. The optimal ultrasound parameters were determined based on the intradermal retention rate, which is defined as the proportion of intradermal retention to the total penetration. Parameters with higher retention rates were considered optimal. To validate the anti-inflammatory efficacy of rutin delivered using the ultrasound-assisted method, we employed a tape-stripping technique to induce inflammation in BALB/c nude mice. Eight mice were assigned to each treatment group: (A) self-repair (control group), (B) regular rutin treatment, and (C) ultrasound-assisted treatment. Results: The research findings indicate that ultrasound frequency and intensity of 1 MHz and 0.2 W/cm², as well as 3 MHz and 0.2 W/cm², result in the maximum proportion of rutin intradermal retention, exhibiting values 1.8 times (using porcine skin) and 2.63 times (using nude mouse skin) higher than those achieved without ultrasound, respectively. Group C showed the shortest recovery time and displayed complete skin barrier function restoration by the fourth day $(p<0.05)$, whereas group A exhibited the slowest recovery. Conclusions: This study offers an innovative approach for the transdermal delivery of rutin to facilitate skin barrier function repair. Full article

In order to investigate the bubble dynamics and thermal effects of stable cavitation under different acoustic fields, this study computes and analyzes a series of DNS (Direct Numerical Simulation) approaches with the VOF (Volume of Fluid) method. The analysis focuses on bubble clusters with a radius of 1.5 μm and a void ratio of ${10}^{-6}$, commonly encountered in ultrasound therapy. Firstly, the results show that the thermal effects of bubble cavitation are non-linearly positively correlated with the ultrasound amplitude and the volume changes of the bubbles. Meanwhile, acoustic scattering caused by ultrasound passing through the bubbles leads to acoustic pressure focusing, intensifying cavitation. Secondly, the thermal effect is most evident at an acoustic frequency of 250 kHz. When the ultrasound input frequency is higher than 250 kHz, acoustic attenuation occurs, while at frequencies lower than 250 kHz, the efficiency of bubbles’ energy absorption reduces. Finally, when the acoustic pressure amplitude on the bubble surface is above 210 kPa, the thermal effect of cavitation is significantly enhanced. However, the temperature rise in the flow domain gradually slows with time and eventually reaches a fixed rate. To sum up, to optimize and control the thermal effects of ultrasound therapy, the ultrasound frequency and amplitude must be carefully selected based on the targeted bubble cluster. Full article