Lasers in Medicine
Year:2023 | Volume:20 | Issue:2|Papers Count:5

Introduction: The skin is considered the first barrier against the penetration of laser light into the body, which causes limitations in imaging or treatment with laser light. The constituents of the skin, which are mainly proteins, lipids, interstitial water, and blood vessels, cause severe light scattering and limit the penetration of light into the deep tissues. This limitation causes the lack of access to structural information and tissue constituents by light and a decrease in the resolution of optical imaging. In this study, using semi-natural HPMC polymer, sorbitol, coconut oil and Tween 20 (called CSC1 and CSC2 for short), the optical parameters of the skin tissue sample were determined by the diffuse reflection spectrum (DRS) method. Research method: DRS was used to obtain the reflection and transmission spectra of the tissue. Then, by using the obtained values and placing them in the Kramers-Kronig relationship, the refractive index can be obtained before and after applying optical clearing agent. Also, other optical parameters such as absorption coefficient, total attenuation coefficient and diffusion coefficient have been calculated from reflection and transmission spectra. Findings: The effect of using optical clearing agent (CSC1, CSC2) on variation of optical properties of sample (refractive index, absorption coefficient, and diffusion coefficient) are measured. Conclusion: The results show that the semi-natural HPMC polymer, which played a role in maintaining the structure of the solution, was effective. Therefore, it can be concluded that the CSC2 could better clear the sample, and it improves the optical depth.

Due to the increasing importance of repairing and rejuvenating different tissues, it is necessary to pay attention to the development of treatment methods to improve treatment results. Low-level lasers are currently used to repair skin tissues. The carboxytherapy method has become particularly important due to its non-invasive treatment. In this method, some carbon dioxide is injected into the tissue. It is produced naturally by the cells of the body, but when the amount of CO2 becomes too much, it forces the body to respond. When carbon dioxide enters the body, the circulatory system in the treated area is stimulated. And then tries to control the condition using blood vessels. Due to the clinical effects of low-level laser and also the carboxytherapy method, it is necessary to study carboxy effects and simultaneously the low-level laser at the cellular level. In this study, the proliferation and viability of Adipose Mesenchymal Stem cells (MSC) have been studied under Laser and carboxy therapy treatments to help develop more effective protocols. Materials and Methods: Adipose Mesenchymal Stem cells were cultured in DMEM F12 + 10% fetal bovine serum (FBS), 100 U/ml penicillin and 100 mg/ml streptomycin. The cells were placed in an incubator with 5% CO2 humidified atmosphere at 37°C. MSC stem cells were irradiated by low-level laser with various doses of 2, 3, 5 and 7 J/cm2 and also cells were exposed to carboxy with different concentrations (with speeds and Different volumes) by Carboxy Therapy device. viability of cells were done by MTT test. Results: The results of this study illustrated the viability and proliferation of cells under the laser and carboxy therapy increased and at the simultaneous laser and carboxy treatment showed further increase than the control group. Discussion: Based on the findings of this study, the use of carboxytherapy as well as the simultaneous use of laser with an optimal dose can be used as an alternative method in skin repair.

Background and purpose: Brain tumors are the consequence of abnormal growth of cells, which may be benign or malignant depending on the nature of the constituent cells. Glioblastoma multiforme (GBM) is one of the most prevalent types of central nervous system tumors. Due to the resistance of glioblastoma tumor to chemotherapy and radiotherapy and the impracticality of complete tumor removal because of its aggressive nature, finding a novel approach is always of great interest. Studies conducted under laboratory conditions indicate that cold plasma destroys cancer cells without harming normal cells. Owing to the complex nature of plasma, its biological effects rest on the characteristics of the source and the type of target being treated. Therefore, in this study, two basic issues including the optimization of plasma jet voltage, time and distance for the treatment of glioblastoma cancer cell line and the effect of a mixture of 5% molecular oxygen gas with helium and argon working gases on the viability of these cells were investigated. Materials and methods: Human glioblastoma cancer cell line U-87 MG was purchased from the cell bank of Pasteur Institute of Iran. For the optimization to occur, five working voltages, three plasma nozzle-to-cell distances and a treatment duration were considered, and the viability of the treated cells was measured by MTT test and based on the manufacturer's protocol. After configuring the experiment under optimal conditions, five treatment durations were investigated. In the experiment to investigate the effect of plasma jet working gas on the viability of cancer cells, 5% oxygen gas was added to helium or argon working gas and the results were compared. All statistical analyses were performed using SPSS and Statistica softwares. Results: The results of voltage and distance optimization demonstrated that the working voltage of 4. 5 kV and 4 cm distance proves to be more effective on the programmed death of U-87 MG cells for the selected plasma jet configuration. In addition, the results showed the inverse dependence of treatment time and survival of U-87 MG cells. The combination of 5% oxygen molecular gas with helium and argon led to an increase in survival rate and as a result, a decrease in plasma effectiveness. Conclusion: In general, the present study indicated that different parameters of plasma jet, including voltage, duration of treatment, distance and type of working gas have an effect on the viability of U-87 MG cells, and the optimal treatment conditions for each cell line are specific according to the type of the device.

Nowadays, the presence of antibiotics in the environment has increasingly caused concern. Antibiotic contamination in the environment leads to the formation of antibiotic-resistant genes and antibiotic-resistant bacteria. The discharge of hospital, industrial, agricultural and local wastewater is the main route of antibiotic entry into the environment. Studies show that the conventional water treatment processes are not efficient and specifically designed to remove these polar compounds, which are mostly water-soluble, non-volatile and non-biodegradable. To destroy these pollutions, many researchers have paid attention to various technologies based on abundant sources and clean energy, such as photocatalysis, Photo-Fenton, UV-H2O2, ozonation, sonolysis and sonocatalysis. Although the contaminated water is very turbid and obscure in many areas that light can hardly penetrate into the contaminated water and limits the photocatalytic ability. Semiconductor-based sonocatalysis has many advantages in antibiotic removal applications. Because the ultrasound waves can spread well in any aqueous environment and play a sonocatalytic effect. The effectiveness of photocatalytic and sonocatalytic processes is related to factors such as irradiation time, photocatalyst dose, pH, etc. Semiconductors such as TiO2, ZnO, SnO2, and ZrO2 participate in sonocatalytic processes due to their ability to promote the valence band electron to the conduction band, leaving the hole behind, and produce free radicals for the oxidation of organic compounds. In this article, we try to provide an overview of the sonocatalytic applications of nanoparticles in the degradation of antibiotics.

Introduction: For first time at 2003, researchers realized that plasmonic could be amplified using stimulated emission, which this concept has caused emerging "Plasmonic Lasers" or "Spasers" (Surface Plasmon Amplification by Stimulated Emission of Radiation). Spasers are nanoscale and subwavelength lasers investigated and used in various fields such as medical. Detect and therapy of cancer and drug delivery are some of their applications in medical. To detect tumors from healthy cells, cancer cells are realized using spaser Nano laser even in deep tissues. In one method, graphene and nanotubes can be pushed to cancer cells and destroy them with laser radiation, or aluminum nanoparticles due to their properties would be used in this way. Spasers have been used as optical probes, to attach CTCs and make them to small pieces. Spasers are introduced in drug delivery in skin field, too, in which method the drug delivery the disadvantages of usual methods are not seen. Research method: This article is presented based on investigations and studies which are done in mediclal field before, to show plasmonic lasers applications. Findings: Based on unique properties of plasmonic and materials such as carbon nanotubes, Nano-shells and so on in nanotechnology, integrating lasers and such materials we can reach to significant results and findings in medical field. Conclusion: Technology goes on and affect all sciences such as medicine. By integrating lasers and palsmonics, new useful and significant finding could be achieved without having usual and common disadvantages of conventional methods. This method can be used in diagnose and therapy of cancer and drug delivery, that are discussed briefly here.