Effects of 3D Postural Correction and Abdominal Muscle Contraction on the Symmetry of the Transverse Abdominis and Spinal Alignment in Patients with Idiopathic Scoliosis.

This study aimed to investigate the effectiveness of 3D postural correction (3DPC) using corrective cushions (CCs) and abdominal muscle contraction (AMC) on the thickness symmetry of the transversus abdominis (TrA) and spinal alignment in patients with idiopathic scoliosis (IS). In the first experiment, ultrasound measurements were taken of the TrA thickness on both the convex and concave sides of the lumbar curve in the supine position during AMC and non-AMC without 3DPC, and during AMC and non-AMC with 3DPC using CCs, in 11 IS patients. In the second experiment, 37 IS patients participated in a four-week 3DPC exercise program that aimed to maintain TrA thickness symmetry based on the results of the first experiment. The study found that TrA thickness symmetry significantly increased after 3DPC using CCs and combined with AMC (p < 0.05). Additionally, the Cobb angles and trunk rotation angles showed significant decreases, and trunk expansion showed a significant increase (p < 0.05). These results indicate that the simultaneous application of 3DPC and AMC is the most effective way to achieve TrA thickness symmetry in IS patients. Therefore, 3DPC and AMC should be considered as crucial elements in exercise interventions for IS patients.

Evaluation of the resection efficiency and safety of an enhanced power plasma generator using cadaveric intervertebral discs.

Plasma energy has been used to provide minimally invasive interventional treatment for spinal problems. However, this procedure has been used for limited indications mainly because of its small resection range. To overcome this problem, we designed the enhanced power plasma device. This device seeks to maximize the resection area by modifying the electrode arrangement and enhancing the maximum electric power. The purpose of this study is to assess the efficiency and safety of this newly designed plasma generator, a device for percutaneous disc decompression. We performed an intradiscal procedure on 7 fresh human cadaver lumbar spine specimens using the enhanced power plasma under C-arm fluoroscopic guidance at various voltages. As a result, the volume of the removed area was proportional to the applied magnitude of the electric power level. In particular, under the high-power level condition after 500 s treatment, nearly the entire nucleus pulposus was eliminated. The generated plasma density also tends to grow along with the given electric power. The highest level of temperature rise did not exceed the level that would lead to degeneration in the collagen tissue of the intervertebral disc. Histopathologic examination also demonstrated that there was no thermal damage to the surrounding neural tissues. In conclusion, we speculate that the concepts of this newly designed enhanced plasma generator could be applied to remove huge disc materials without thermal or structural damage to the adjacent target tissues in future spine clinics.

Safety evaluation of atmospheric pressure plasma jets in in vitro and in vivo experiments.

PURPOSE: The atmospheric pressure plasma jet (APPJ) has been introduced as an effective disinfection method for titanium surfaces due to their massive radical generation at low temperatures. Helium (He) has been widely applied as a discharge gas in APPJ due to its bactericidal effects and was proven to be effective in our previous study. This study aimed to evaluate the safety and effects of He-APPJ application at both the cell and tissue levels. METHODS: Cellular-level responses were examined using human gingival fibroblasts and osteoblasts (MC3T3-E1 cells). He-APPJ was administered to the cells in the experimental group, while the control group received only He-gas treatment. Immediate cell responses and recovery after He-APPJ treatment were examined in both cell groups. The effect of He-APPJ on osteogenic differentiation was evaluated via an alkaline phosphatase activity assay. In vivo, He-APPJ treatment was administered to rat calvarial bone and the adjacent periosteum, and samples were harvested for histological examination. RESULTS: He-APPJ treatment for 5 minutes induced irreversible effects in both human gingival fibroblasts and osteoblasts in vitro. Immediate cell detachment of human gingival fibroblasts and osteoblasts was shown regardless of treatment time. However, the detached areas in the groups treated for 1 or 3 minutes were completely repopulated within 7 days. Alkaline phosphatase activity was not influenced by 1 or 3 minutes of plasma treatment, but was significantly lower in the 5 minute-treated group (P=0.002). In vivo, He-APPJ treatment was administered to rat calvaria and periosteum for 1 or 3 minutes. No pathogenic changes occurred at 7 days after He-APPJ treatment in the He-APPJ-treated group compared to the control group (He gas only). CONCLUSIONS: Direct He-APPJ treatment for up to 3 minutes showed no harmful effects at either the cell or tissue level.

Non-thermal dielectric-barrier discharge plasma induces reactive oxygen species by epigenetically modifying the expression of NADPH oxidase family genes in keratinocytes.

We have previously shown that non-thermal dielectric-barrier discharge (DBD) plasma induces the generation of reactive oxygen species (ROS) in cells; however, the underlying mechanism has not been elucidated. This study aimed to identify the mechanisms through which DBD plasma induces the expression of NADPH oxidase (NOX) family members by epigenetic modification in human keratinocytes (HaCaT). Cell exposure to DBD plasma in 10% oxygen and 90% argon resulted in the generation of ROS, triggering oxidative stress that manifested in various forms, including lipid membrane peroxidation, DNA base modification, and protein carbonylation. DBD plasma upregulated the expression of NOX1, NOX5, and DUOX2 at the mRNA and protein levels; and siRNAs targeting NOX1, NOX5, and DUOX2 attenuated the generation of DBD plasma-induced ROS. DBD plasma upregulated the transcriptional activators TET1, MLL1, and HAT1 and downregulated the transcriptional repressors DNMT1, EZH2, and HDAC1. Additionally, DBD plasma increased the binding of transcriptional activators and decreased the binding of transcriptional repressors to the DUOX2 promoter. Methyl-specific polymerase chain reaction and bisulfite sequencing indicated that DBD plasma decreased methylation at the DUOX2 promoter. These results suggest that DBD plasma induces ROS generation by enhancing the expression of the NOX system through epigenetic DNA and histone modifications.

The bactericidal effect of an atmospheric-pressure plasma jet on Porphyromonas gingivalis biofilms on sandblasted and acid-etched titanium discs.

PURPOSE: Direct application of atmospheric-pressure plasma jets (APPJs) has been established as an effective method of microbial decontamination. This study aimed to investigate the bactericidal effect of direct application of an APPJ using helium gas (He-APPJ) on Porphyromonas gingivalis biofilms on sandblasted and acid-etched (SLA) titanium discs. METHODS: On the SLA discs covered by P. gingivalis biofilms, an APPJ with helium (He) as a discharge gas was applied at 3 different time intervals (0, 3, and 5 minutes). To evaluate the effect of the plasma itself, the He gas-only group was used as the control group. The bactericidal effect of the He-APPJ was determined by the number of colony-forming units. Bacterial viability was observed by confocal laser scanning microscopy (CLSM), and bacterial morphology was examined by scanning electron microscopy (SEM). RESULTS: As the plasma treatment time increased, the amount of P. gingivalis decreased, and the difference was statistically significant. In the SEM images, compared to the control group, the bacterial biofilm structure on SLA discs treated by the He-APPJ for more than 3 minutes was destroyed. In addition, the CLSM images showed consistent results. Even in sites distant from the area of direct He-APPJ exposure, decontamination effects were observed in both SEM and CLSM images. CONCLUSIONS: He-APPJ application was effective in removing P. gingivalis biofilm on SLA titanium discs in an in vitro experiment.

Optimal Parameters for Intervertebral Disk Resection Using Aqua-Plasma Beams.

OBJECTIVE: A minimally invasive procedure for intervertebral disk resection using plasma beams has been developed. Conventional parameters for the plasma procedure such as voltage and tip speed mainly rely on the surgeon's personal experience, without adequate evidence from experiments. Our objective was to determine the optimal parameters for plasma disk resection. METHODS: Rate of ablation was measured at different procedural tip speeds and voltages using porcine nucleus pulposi. The amount of heat formation during experimental conditions was also measured to evaluate the thermal safety of the plasma procedure. RESULTS: The ablation rate increased at slower procedural speeds and higher voltages. However, for thermal safety, the optimal parameters for plasma procedures with minimal tissue damage were an electrical output of 280 volts root-mean-square (Vrms) and a procedural tip speed of 2.5 mm/s. CONCLUSION: Our findings provide useful information for an effective and safe plasma procedure for disk resection in a clinical setting.

Mutual Interaction between Plasma Characteristics and Liquid Properties in AC-driven Pin-to-Liquid Discharge.

This study investigated the mutual interaction between the plasma and plasma treated water (PTW). Many works have shown that the plasma treatment decreases the pH of PTW due to nitric oxide electrolyte ion but the interactions between PTW and the plasma are still largely unknown. We investigated the effect of PTW on a plasma as well as the effect of a plasma on PTW using a pin-to-liquid discharge system. It is found that PTW affects not only the chemical properties but also the physical properties of the plasma such as breakdown voltage and concentration of plasma column. The decrease of the liquid surface tension of PTW due to nitric oxide electrolyte ion from the plasma results in the increase of plasma current onto the surface of PTW and vice versa. The feedback process will be continued until the transition from normal discharge to abnormal discharge. These results can be basic data for the development of plasma sources to treat liquids.

DUOX2-mediated production of reactive oxygen species induces epithelial mesenchymal transition in 5-fluorouracil resistant human colon cancer cells.

The therapeutic benefits offered by 5-fluorouracil (5-FU) are limited because of the acquisition of drug resistance, the main cause of treatment failure and metastasis. The ability of the cancer cells to undergo epithelial-mesenchymal transition (EMT) contributes significantly to cancer metastatic potential and chemo-resistance. However, the underlying molecular mechanisms of 5-FU-resistance have remained elusive. Here, we show that reactive oxygen species (ROS), produced by dual oxidase 2 (DUOX2), promote 5-FU-induced EMT. First, we showed that 5-FU-resistant SNUC5 colon cancer cells (SNUC5/FUR cells) undergo EMT by analyzing the expression of EMT markers such as N-cadherin, vimentin and E-cadherin. In addition, we found that the resistant cells expressed higher levels of Snail, Slug, Twist and Zeb1, which are all critical EMT regulators and had enhanced migratory and invasive capabilities. Furthermore, SNUC5/FUR cells had increased level of DUOX2, resulting in increased ROS level. This effect was due to the enhanced binding of the ten eleven translocation 1 (TET1) demethylase to the DUOX2 promoter in the SNUC5/FUR cells. Importantly, silencing of TET1 reversed the effects of 5-FU on the cells. Finally, the antioxidant N-acetylcysteine attenuated the effects of 5-FU on EMT and metastasis. Our study demonstrates the existence of a TET1/DUOX2/ROS/EMT axis that could play a role in colon cancer chemo-resistance and the aggressiveness of this cancer.

Feasibility of Navigable Percutaneous Disk Decompressor (L'DISQ-C) for Cervical Disk Herniation.

OBJECTIVE: To assess the procedural efficacy and safety of a Navigable Percutaneous Disk Decompressor (L'DISQ-C) for cervical disk herniation. METHODS: We performed intradiskal decompression on cervical spine specimens from five human cadavers using the L'DISQ-C under C-arm fluoroscopic guidance. We evaluated our success for positioning the navigable wand tip into the target region and recorded temperature variation at various distances from the wand tip in the cervical nucleus pulposus. The histologic effect of plasma decompression was examined microscopically using harvested tissues adjacent to the procedure site. RESULTS: We successfully navigated the tip of the L'DISQ-C into the target region of the posterior cervical disks on the first insertion attempt in all C3-C4 to C6-C7 disks and in 50% of the C2-C3 and C7-T1 disks. The average temperature elevations within the nucleus pulposus ranged from 4.14 ± 0.08°C to 12.17 ± 0.76°C at various distances from the wand tip with or without saline infusion. A histologic examination showed only minor denaturation at the marginal border of the procedure tract. CONCLUSION: We effectively navigated the L'DISQ-C wand tip into the posterior target region of six cadaveric cervical disks and performed percutaneous resection of the target disk tissues without significant thermal or structural damage to adjacent tissues.