The structural effect of high intensity ultrasound on peritoneal tissue: a potential vehicle for targeting peritoneal metastases

Background. High‐intensity ultrasound (HIUS) has been studied for the past two decades as a new therapeutic option for solid tumor direct treatment and a method for better chemotherapy delivery and perfusion. This treatment approach has not been tested to our knowledge in peritoneal metastatic therapy, where limited tissue penetration of intraperitoneal chemotherapy has been a main problem. Both liquid instillations and pressurized aerosols are affected by this limitation. This study was performed to evaluate whether HIUS improves chemotherapy penetration rates. Methods. High-intensity ultrasound (HIUS) was applied for 0, 5, 30, 60, 120, and 300 seconds on the peritoneal tissue samples from fresh postmortem swine. Samples were then treated with doxorubicin via pressurized intraperitoneal aerosol chemotherapy (PIPAC) under 12 mmHg and 37°C temperature. Tissue penetration of doxorubicin was measured using fluorescence microscopy on frozen thin sections. Results. Macroscopic structural changes, identified by swelling of the superficial layer of the peritoneal surface, were observed after 120 seconds of HIUS. Maximum doxorubicin penetration was significantly higher in peritoneum treated with HIUS for 300 seconds, with a depth of 962.88 ± 161.4 μm (p < 0.05). Samples without HIUS had a penetration depth of 252.25 ± 60.41. Tissue penetration was significantly increased with longer HIUS duration, with up to 3.8-fold increased penetration after 300 sec of HIUS treatment. Conclusion. Our data indicate that HIUS may be used as a method to prepare the peritoneal tissue for intraperitoneal chemotherapy. Higher tissue penetration rates can be achieved without increasing chemotherapy concentrations and preventing structural damage to tissue using short time intervals. More studies need to be performed to analyze the effect of HIUS in combination with intraperitoneal chemotherapy.

Download Full-text

Enabling Microparticle Imprinting to Achieve Penetration and Local Endurance in the Peritoneum via High-Intensity Ultrasound (HIUS) for the Treatment of Peritoneal Metastasis

International Journal of Surgical Oncology ◽

10.1155/2020/9679385 ◽

2020 ◽

Vol 2020 ◽

pp. 1-7

Author(s):

Agata Mikolajczyk ◽

Tanja Khosrawipour ◽

Alice Martino ◽

Joanna Kulas ◽

Marek Pieczka ◽

...

Keyword(s):

High Intensity ◽

Selection Process ◽

Chemical Properties ◽

Strontium Aluminate ◽

High Intensity Ultrasound ◽

Time Intervals ◽

Tissue Samples ◽

Thin Sections ◽

Peritoneal Tissue ◽

Physical And Chemical

Introduction. Micro- and nanoparticles, with their submicron size, the versatility of physical and chemical properties, and easily modifiable surface, are uniquely positioned to bypass the body’s clearing systems. Nonetheless, two main problems with micro- and nanoparticles arise which limit the intraperitoneal application. The study was performed to evaluate whether HIUS enables the imprinting of microparticles and, therefore, enhances penetration and local endurance in the peritoneum. Methods. High-intensity ultrasound (HIUS) at 20 kilohertz with an output power of 70 W was applied on peritoneal tissue samples from fresh postmortem swine for different time intervals. Before the HIUS application, the surface of the samples was covered with strontium aluminate microparticles before analysis via electron microscopy. In-tissue strontium aluminate penetration and particle distribution size were measured using fluorescence microscopy on frozen thin sections. Results. With increasing HIUS durations (1 versus 5 minutes), increasing strontium aluminate particles were detected in the peritoneum. HIUS leads to a particle selection process with enhancing predominantly the penetration of smaller particles whereas larger particles had a harder time penetrating the peritoneum. Smaller particles were detected up to 277 µm ± 86 µm into the peritoneum. Conclusion. Our data indicate that HIUS might be used as a method to prepare the peritoneal tissue for micro- and nanoparticles. Higher tissue penetration rates without the increase and longer local endurance of the applied substance could be reached. More studies need to be performed to analyze the effect of HIUS in enhancing intraperitoneal drug applications.

Download Full-text

Non pharmacological high-intensity ultrasound treatment of human dermal fibroblasts to accelerate wound healing

Scientific Reports ◽

10.1038/s41598-021-81878-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jeong Yu Lee ◽

Dae-Jin Min ◽

Wanil Kim ◽

Bum-Ho Bin ◽

Kyuhan Kim ◽

...

Keyword(s):

Wound Healing ◽

High Intensity ◽

Mapk Pathway ◽

Dermal Fibroblasts ◽

Ultrasound Treatment ◽

Type I ◽

Human Dermal Fibroblasts ◽

Short Term ◽

High Intensity Ultrasound ◽

Extracellular Matrix Components

AbstractInspired by the effectiveness of low-intensity ultrasound on tissue regeneration, we investigated the potential effect of short-term high-intensity ultrasound treatment for acceleration of wound healing in an in vitro wound model and dermal equivalent, both comprising human dermal fibroblasts. Short-term ultrasound of various amplitudes significantly increased the proliferation and migration of fibroblasts and subsequently increased the production of the extracellular matrix components fibronectin and collagen type I, both of which are important for wound healing and are secreted by fibroblasts. In addition, ultrasound treatment increased the contraction of a fibroblast-embedded three-dimensional collagen matrix, and the effect was synergistically increased in the presence of TGF-β. RNA-sequencing and bioinformatics analyses revealed changes in gene expression and p38 and ERK1/2 MAPK pathway activation in the ultrasound-stimulated fibroblasts. Our findings suggest that ultrasound as a mechanical stimulus can activate human dermal fibroblasts. Therefore, the activation of fibroblasts using ultrasound may improve the healing of various types of wounds and increase skin regeneration.

Download Full-text