Yoshimi Harada

Ultrasound activation of TiO2 in melanoma tumors

Sonodynamic therapy (SDT) is a new modality using ultrasound (US) to activate certain chemical sensitizers for cancer therapy. In this study, the effect of US combined with a nanoparticle titanium dioxide (TiO(2)) on melanoma cell was investigated in vitro and in vivo. Melanoma cells (C32) were irradiated with US in the presence and/or absence of TiO(2). Cell viability was measured immediately after US irradiation (1MHz, 0.5 and 1.0W/cm(2) for 10s). The effect of the combination of TiO(2) and US exposure (1MHz, 1.0W/cm(2), 2 min duration) on subcutaneously implanted C32 solid tumors in mice were investigated by measuring tumor volume regression. The cell viability was significantly decreased only after US irradiation in the presence of TiO(2). In vivo results showed significant inhibition of tumor growth in groups treated with TiO(2) and US. To our knowledge, this is the first report to demonstrate the cell killing effect of TiO(2) nanoparticles under the irradiation US in vitro and in vivo.

Synergistic effect of ultrasound and antibiotics against Chlamydia trachomatis-infected human epithelial cells in vitro

To investigate whether or not the combined ultrasound and antibiotic treatment is effective against chlamydial infection, a new ultrasound exposure system was designed to treat chlamydia-infected cells. First, the minimum inhibitory concentrations of antibiotics against Chlamydia trachomatis were determined. Infected cultures were treated with antibiotics then sonicated at intensity of 0.15 or 0.44 W/cm(2) with or without Bubble liposomes. After 48 or 72 h after infection, chlamydial inclusions were stained and examined by fluorescence microscopy. The internalization of dextran-fluorescein conjugates by ultrasound irradiation with Bubble liposomes was observed by fluorescence microscopy. The results showed that application of nanobubble-enhanced ultrasound caused no significant effect on cell viability and chlamydial infectivity. However, Doxycycline (1/2 MIC) or CZX (1.0 μg/ml) in combination with nanobubble-enhanced ultrasound dramatically reduced the number of inclusions compared with that administered with antibiotics only. Bubble dose-dependent synergy was also observed. After ultrasound irradiation at intensity of 0.44 W/cm(2) on the presence of Bubble liposomes, 10% of HeLa cells were observed to have internalized the dextran molecules. This study suggests the possibility of using nanobubble-enhanced ultrasound to deliver antibiotic molecules into cells to eradiate intracellular bacteria, such as chlamydiae, without causing much damage to the cells itself.

Ultrasound-mediated interferon β gene transfection inhibits growth of malignant melanoma

We investigated the effects of ultrasound-mediated transfection (sonotransfection) of interferon β (IFN-β) gene on melanoma (C32) both in vitro and in vivo. C32 cells were sonotransfected with IFN-β in vitro. Subcutaneous C32 tumors in mice were sonicated weekly immediately after intra-tumor injection with IFN-β genes mixed with microbubbles. Successful sonotransfection with IFN-β gene in vitro was confirmed by ELISA, which resulted in C32 growth inhibition. In vivo, the growth ratio of tumors transfected with IFN-β gene was significantly lower than the other experimental groups. These results may lead to a new method of treatment against melanoma and other hard-to-treat cancers.

Therapeutic potential of low-intensity ultrasound (part 2): biomolecular effects, sonotransfection, and sonopermeabilization

Part one of this review focused on the thermal and mechanical effects of low-intensity ultrasound (US). In this second and final part of the review, we will focus on and discuss various aspects of low-intensity US, with emphasis on the biomolecular effects, US-mediated gene transfection (sonotransfection), and US-mediated permeabilization (sonopermeabilization). Sonotransfection of different cell lines in vitro and target tissues in vivo have been reported. Optimization experiments have been done and different mechanisms investigated. It has also been found that several genes can be up-regulated or down-regulated by sonication. As to the potential therapeutic applications, systemic or local sonotransfection might also be a safe and effective gene therapy method in effecting the cure of local and systemic disorders. Gene regulation of target cells may be utilized in modifying cellular response to a treatment, such as increasing the sensitivity of diseased cells while making normal cells resistant to the side effects of a treatment. Advances in sonodynamic therapy and drug sonopermeabilization also offer an ever-increasing array of therapeutic options for low-intensity US.

Aesthetic Total Reconstruction of Lower Eyelid Using Scapha Cartilage Graft on a Vascularized Propeller Flap.

Background: The aim of this study was to review the results of a cohort of patients based on our experience with a new technique for total lower eyelid reconstruction after a large defect caused by malignant tumor and trauma. A scapha cartilage graft with small skin on a vascularized propeller flap was used for 16 cases requiring lower eyelid reconstruction. Methods: Patients were identified from a database, and a retrospective case note review was conducted. The scapha cartilage graft was sutured to the margin of the defect of the palpebral conjunctiva and tarsus. The propeller flap, rotated by a perforator-based lateral orbital flap or a subcutaneous-based nasolabial flap, was vascularized on the scapha cartilage graft as anterior lining of the lower eyelid. The follow-up, including results of slit-lamp examination, lasted for varying periods, but often it was for 12 months. Results: The scapha cartilage graft with small skin on a vascularized propeller flap was viable in all cases. Slit-lamp examination detected no irritation or injury of the conjunctiva and cornea, and visual acuity was maintained in all cases. A deformity in the donor helix by this technique was also improved by getting a smaller skin harvested from the scapha. Conclusion: Use of the scapha cartilage graft with small skin on a vascularized propeller flap allows for a good fit to the orbit, short operative time under local anesthesia, good graft viability, and a good esthetic result with minimal donor site morbidity.

Growth inhibition of neurofibroma by ultrasound-mediated interferon γ transfection

PurposeWe have previously shown that ultrasound-mediated transfection (sonotransfection) can be optimized using a concept based on the ultrasound-induced apoptosis produced in our in vitro experiments. At optimized conditions, we have shown, using five cancer cell lines, that sonotransfection is superior to other conventional nonviral methods. Interferon gamma (IFN-γ) transfection using lipofection has been found to markedly inhibit the proliferation of neurofibroma cell lines. In this study, we investigated whether sonotransfection of IFN-γ to neurofibroma cell lines can suppress cell proliferation.MethodsThe ultrasound device used was the SonoPore KTAC-4000, which is capable of various acoustic settings. Ultrasound transducers at an oscillation frequency of 1.011 MHz were used; the potential ideal conditions were an intensity of 0.17 W/cm2 at a burst frequency of 0.5 Hz, 25% duty factor, and 30-s sonication duration. Cells were assayed at 3 and 5 days after sonication.ResultsThe transfection efficiency was found to be 12%. The ultrasound-treated cells were successfully transfected with IFN-γ genes as detected by enzyme-linked immunosorbent assay, and the cell growth ratio in the IFN-γ sonotransfection group tended to be lower than that in the other experimental groups.ConclusionThese results suggested that IFN-γ sonotransfection could potentially become a nonsurgical method for treating skin lesions such as neurofibromas.

The effect of different positions on lower limbs skin perfusion pressure

We have encountered situations of patients with critical limb ischemia accompanied by pain at rest and necrosis, who hang their legs down from the bed during sleep. This lower limb position is known to be a natural position, which reduces pain in the lower extremity induced by ischemia. However, the effect of this position on blood flow of the lower extremity is poorly understood. We studied whether measurements of skin perfusion pressure (SPP) changes by leg position and the difference between healthy adults and patients with critical limb ischemia. The subjects of this study were 10 healthy adults and 11 patients with critical limb ischemia. Patients with critical limb ischemia, including both dorsum of foot and plantar of foot, having SPP of lower limbs of less than 40 mmHg (supine position) were the object of this study. SPP was measured on four positions (supine position, lower limbs elevation position, sitting position, and reclining bed elevation of 20° position). In sitting position, both the number of healthy adults and critical patients show significant increases in SPP compared with the other three positions. These results suggest that sitting position is effective to keep good blood stream of lower limbs not only in healthy adults but also in patients with critical limb ischemia. However, an appropriate leg position should not have lower limbs hang downwards for long periods time because edema is caused by the fall in venous return in lower limbs, and the wound healing is prolonged. Our clinical research could be more useful in the future, particularly in developing countries, for surgeons managing wounds in leg and foot and preserving ischemic limbs.

Transconjunctival Approach for Zygomatic Fracture: A Single Surgeon’s Experience of More Than 20 Years

Background: To let experts evaluate a single surgeon’s experience with a combined transconjunctival and intraoral upper vestibular approach in the repair of zygomatic fractures encountered in 46 East Asian patients whom he treated over the past 20 years. Methods: Patients were identified from a database, and a retrospective case note review was conducted. A total of 67 conjunctival and secondary incisions were made on 46 patients for repair of zygomatic fractures. All operative procedures were performed using a combination of transconjunctival and intraoral upper vestibular approaches to repair zygomatic fractures. Results: The infraorbital rim and/or lateral buttress and/or lateral orbit was stabilized with titanium miniplates in 28 patients and absorbable miniplates in 11 patients. Seven patients required only reduction technique with no need of plates. Four cases needed additional canthotomy besides a conjunctival approach. No ectropion or entropion developed in any of the patients. Complications included eyelid laceration during surgery (n = 1), herniation of the conjunctiva (n = 1), temporary pyogenic granuloma of the conjunctiva after surgery (n = 1), and temporary entropion in a secondary incision (n = 1). Conclusions: A combined transconjunctival and intraoral upper vestibular approach in repairing zygomatic fractures is simple, easy, and effective, leaving no conspicuous facial scars. It is vitally important, however, that the surgeon masters the technique of transconjunctival approach well before he has good results in East Asian patients.

In Situ Splitting of a Rib Bone Graft for Reconstruction of Orbital Floor and Medial Wall

In situ splitting of rib bone graft was conducted in 22 patients for the repair of orbital fracture with no other complicating fractures. A bone graft was harvested from the sixth or seventh rib in the right side. The repair of the orbital floor and medial wall was successful in all the cases. Ten patients had bone grafting to the orbital floor, eight had it done onto medial wall, and 4 onto both floor and wall after reduction. The mean length of in situ rib bone graft was 40.9 mm (range, 20–70 mm), the mean width of these was 14.9 mm (range, 8–20 mm). The bone grafting was done by one leaf for 15 cases and two leafs for 7 cases in size of defects. The technique of in situ splitting of a rib bone graft for the repair of the orbital floor and medial wall is a simple and safe procedure, easily taking out the in situ splitting of a rib, and less pain in donor site. It has proved to be an optimal choice in craniofacial reconstruction, especially the defects of orbital floor and medial wall.