International Journal of Biophotonics and Biomedical Optics
Volume:3 Issue: 2, Summer and Autumn 2023

This study has investigated skin toxicity in breast cancer patients undergoing radiation therapy. The study was conducted in 1401 at a radiation therapy center in Yazd city and included 30 patients who have undergone radiation therapy using conventional and hypofractionation methods, and in which the whole or part of the breast has been exposed to radiation. Skin complications of grade skin toxicity during treatment and within 40 days after radiotherapy have been evaluated in both methods. Results have shown that four people (26.6%) have had grade three and six people (40.0%) have had grade two skin toxicity, with conventional treatment having caused more skin complications compared to hypofractionation, which has caused fewer skin toxicity without reducing efficacy. Additionally, the ratio of skin toxicity in the conventional technique has been higher than in the hypofractionation technique after 40 days of radiation therapy. The study has concluded that hypofractionation has resulted in less skin toxicity than conventional treatment.

In radiation therapy, investigating of the effects of the surface flux reaching on the tissue is important in planning the treatment and this requires a precise evaluation of the absorbed dose distribution throughout the irradiated tissue. Therefore, by Monte Carlo simulation with MCNP code, a point source with the size of E with a spectrum width of 0.6 µm with a single energy transfer of 6 MeV to the breast tumor tissue with a size of 2 x 4 x 4 cm and also a density (Kg/m^3) of 11.34 at a fixed depth of 3 cm. It is radiated from a standard phantom (VIP MAN) made of tissue. The results show the highest surface flux that received on the tumor is around 9.97 × 〖10〗^(-6) and is located almost in the center of the tumor in dimensions (-0.75 cm - 1.3 cm) and the less surface flux around the tumor is caused by the rate of the dose which is distributed. Also, the template phenomenon in the creation of electrons is based on the Compton effect, while in the creation of photons, the Compton effect did not occur.

Ceftriaxone is a pharmaceutical compound that causes the pollution of water. In this research, g-C3N4 photocatalyst was synthesized and its efficiency in removal of ceftriaxone was studied. The synthesized g-C3N4 was analyzed using XRD, FTIR, FESEM, EDS, and dot mapping. The effect of the initial concentration of ceftriaxone, dosage of photocatalyst, irradiation time, and pH was studied, and based on these results, the highest removal efficiency of ceftriaxone from the water was obtained at about 83.4% at the concentration of 20 mg/L, pH=2, 0.25 g/500 mL of g-C3N4 photocatalyst at 50 min of irradiation time. This study confirmed that the g-C3N4 photocatalyst can be efficiently removed ceftriaxone from water.

In this work, a biosensor based on a structurally chiral medium (SCM) under the effect of a low-frequency electric field has been designed to detect blood hemoglobin. The introduced structure is irradiated with a circularly polarized light under an electro-optical Pockels effect. A photonic band gap is observed in the transmission spectrum of the right-handed circularly polarized waves, which indicates the circular Bragg phenomenon. The sample layer is placed between two identical SCMs. The transfer matrix method (TMM) is utilized for the evaluation of the sensor performance. The results show that the defect mode is sensitive to any change in the refractive index of the defect layer where the defect layer is infiltrated with samples with different concentrations of blood hemoglobin. Also, it is shown that applying a low-frequency electric field increases the sensitivity of the mentioned sensor. It is observed that the sensitivity can be expanded up to 142.66 nm/RIU by changing the various parameters of the SCM.

The ability of Plasmonic nanoparticles (PNPs) to efficiently convert absorbed light energy into localized heat has made them a popular choice for photothermal medical applications. However, during the photothermal process, the diffusion of localized heat can lead to temperature management challenges. To address this issue, researchers have developed a new generation of PNPs incorporating optical phase transition materials, allowing for tunable photothermal responses without altering the geometry. This tunability is achieved through rapid changes in optical and thermal properties during phase transitions. In this study, we conducted a numerical analysis on the photothermal response of a VO2@Au smart nanoshell in both tumor and healthy liver tissue under irradiation with a nanosecond (5 ns) pulsed laser. To obtain the temperature profile, we solved a coupling problem between electromagnetism and thermodynamics.

Nowadays, scientists are looking to decrease dental faults by presenting new approaches. It is obvious that comprehensive information about the anatomic position of the inferior alveolar neural canal is essential to have the most ideal mandible surgery or systemic tooth implant. Accordingly, we present a new approach in this article that can be used to have 3D segmentation and recognition of the mentioned canal in mandible by CBCT image. This approach includes two main steps. In the first step, we train a full convolutional 3D net (FCN) to reach the ability of section recognition, which can recognize the relevant area of the mandible bone. In the next step, we define a 3D U-net, which is similar to FCN, to segment the inferior Alveolar neural (IAN) canal from the lower jaw. Evaluated on publicly available datasets, our method achieved an average Dice coefficient of 86.61%.

Pseudomonas aeruginosa (P. aeruginosa) is a nosocomial opportunistic pathogen. Considering the importance of biofilm in pathogenicity and resistance of these bacteria, efforts should be made to find new antibacterial compounds.

The Fe3O4 nanoparticles were synthesized by the co-precipitation method and were modified by the AgNO3 reductive solution to investigate influencing of Ag-Fe3O4 nanoparticles on biofilm formation of P. aeruginosa. The synthesized nanoparticles properties were determined by FESEM, DLS, FTIR, XRD and Zeta potential tests.

FESEM and DLS revealed the cubic and smooth structure with average size of 44.36 nm. XRD analyzes confirmed the presence of magnetite core. FTIR spectrum determined the existence of silver plating on the magnetic surface. The Zeta potential results indicated that the magnetic nanoparticle’s surface net charge was 24.4 and the surface net charge for silver modified nanoparticles was -28.3. Finally, after separating 40 isolates of P. aeruginosa among 82 clinical isolates as strong biofilm producers, then the inhibitory effect of synthesised Ag- Fe3O4 nanoparticles on the formation of biofilms was studied using the broth micro-dilution method.

Accordingly, it was proved that Ag-Fe3O4 nanoparticles can be used to treat biofilm infections and were introduced as the new antimicrobial agents