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Purpose: To investigate the short-term effects of low-level lasers (LLLs; also known as lowpower laser therapy) on the structure, genetic, and phenotype of cultured human retinal pigment epithelial (hRPE) cells from both adult and neonatal sources. Methods: Cultivated adult and neonatal hRPE cells were irradiated with two types of LLL (630 nm and 780 nm), 1 min daily for five consecutive days. Results: An increase in doubling time was observed in 630 nm-irradiated adult hRPE cells (P = 0.032). The gene expression profile revealed increased expression of retinoid isomerohydrolase RPE65 (RPE65) (P < 0.01 for 630 nm laser, P < 0.001 for 780 nm laser) and nestin (NES) (P < 0.01 for 630 nm laser) in neonatal hRPE cells, upregulation of RPE65 (P <0.001 for 780 nm laser) and paired box 6 (PAX6) (P < 0.001 for 780 nm laser) genes in adult hRPE cells, and reduced expression of actin alpha 2 (ACTA2) in 780 nm-irradiated adult hRPE cells (P <0.001). Except the significant increase of α-SMA in 780 nm-irradiated neonatal hRPE cells, no significant change was noted in the expressions of other investigated proteins. Conclusion: Short-term irradiation of neonatal and adult hRPE cells with LLLs may induce multipotency at the transcriptional level. Irradiation of neonatal hRPE cells with LLLs can be associated with increased risk of myofibroblastic transformation; however, adult hRPE cells irradiated with the 780 nm laser have minimal risk of myofibroblastic differentiation. It seems that the 780 nm laser may be a promising option for future photobiomodulation in retinal degenerations in adults. [ABSTRACT FROM AUTHOR]

Introduction: Diabetic peripheral neuropathy (DPN) is the most common complication of diabetes patients. Among different therapeutic approaches for treating DPN, low-level laser therapy (LLLT) or photobiomodulation (PBM) is a new promising non-invasive technique. This study aims to evaluate the effect of visible and infra-red LLLT on DPN. Methods: Sixty DPN patients enrolled in a randomized-controlled study. The patients were randomly divided into the same population of control and laser groups. The patients in the laser group received LLLT with two wavelengths of 630 and 819 nm and conventional therapy, and those in the control group received conventional therapy alone. Irradiation of the patients lasted 15 minutes per session, and it was performed over the surface of each foot three times a week for 12 sessions. The patients were evaluated at baseline and at the end of the study with the Michigan Neuropathy Screening Instrument (MNSI) and microfilament test. Results: Patients' sensation in the right foot in the monofilament test had increased from 22 (84.6%) to 26 (86.7%) (P = 0.000), and in the left foot it had increased from 20 (80%) to 25 (86.2%) (P = 0.001). The mean and standard deviation of the scores of section A of the Michigan questionnaire showed a statistically significant difference between the two groups (P < 0.05), but the B part scores of the Michigan test did not show a significant difference. Conclusion: This study showed that the visible and infra-red LLLT significantly improved the symptoms of diabetic neuropathy without any side effects. [ABSTRACT FROM AUTHOR]

Introduction: This study aimed to investigate the absorbed dose of scatter radiation in coronary angiography. Material and Methods: The scatter radiation dose was measured for 20 patients at four different heights (50,100, 150, and 165 cm) from the floor. The spatial dose was measured by RTI Piranha r100b solid-state dose probe at different points around the patient in an actual clinical situation and with a phantom. Also, the measurement was repeated using a designed phantom in fluoroscopy and cine mode in posterior anterior (PA), left lateral (LLAT), left posterior oblique (LPO45°), right posterior oblique (RPO45°), and right-lateral (RLAT)projections. Organ-absorbed doses were normalized to dose area product (DAP). Results: The dose rate at different heights between the projections on the patient and the phantom as well as organ dose DAP conversion coefficients were different (p10.05). It was found that the dose rate changes in fluoroscopic mode compared to cine mode are significantly different (p = 0.001). The dose rate in cine mode is approximately four times that in fluoroscopy mode. The dose rate around the cardiologist's waist could be reduced by 37 - 43 % with a displacement of 20cm away. In this study, the effective dose rate received by the cardiologist's eyes was higher than those reported by ICRP. Conclusion: Taking a suitable projection could reduce the dose rate delivered to the angiography team. Further studies should be conducted about the effect of different projections with the same clinical use on dose distribution in coronary angiography to provide the best working conditions for physicians and staff. [ABSTRACT FROM AUTHOR]

Background: Oral mucositis is among the most important adverse effects of chemotherapy and bone marrow transplantation and prevention from this side effect is important to improve the situations in patients. Hence, in this study the main aim was to determine the effects of low-level laser therapy on mucositis in patients under chemotherapy and bone marrow transplantation. Materials and Methods: In this randomized controlled clinical trial, 60 consecutive patients under chemotherapy and bone marrow transplantation in a training hospital in 2018 were enrolled and randomly assigned to receive either low-level laser therapy (630 and 780 nm) or off-laser. Finally, the frequency rate and severity of mucositis (grades 0 to 4 according to WHO severity index) were determined and compared across the groups. Results: Mucositis was present in 30% and 56.7% in laser and control groups, respectively with statistically significant difference (p=0.037). The severity of mucositis was same across the laser and control groups (p=0.785). Conclusion: Low-level laser therapy is an effective modality for preventing from mucositis in patients treated by chemotherapy and bone marrow transplantation. Accordingly, utilization of this safe and effective therapeutic method is recommended. [ABSTRACT FROM AUTHOR]

This study represents an update of Tehran population exposure from the diagnostic nuclear medicine procedures and the annual collective effective dose during 2011-14. The diagnostic nuclear medicine procedures data were collected from 58 out of 60 nuclear medicine centers in Tehran and were composed of the type and frequency of diagnostic examinations, radiopharmaceuticals used, administered activities, and age distribution of the patients. The annual number of examinations per 1000 population increased from 13.73 in 2011 to 22.59 in 2014 with an increase of 64.53% during 4 years. Most frequent examinations were cardiac (71.05%), bone (9.80%) and thyroid (7.26%) averaged over the 5 years. The collective effective dose increased from 807.74 person-Sv in 2011 to 1413.81 person-Sv in 2014. The effective dose per capita increased from 44.06 µSv in 2011 to 120.91 µSv in 2014, could be because of 70% increase of examinations, but ~3.42% increase in the population of Tehran. [ABSTRACT FROM AUTHOR]

Introduction: Unhealthy lifestyle choices such as alcohol, chemicals, and heat stress can worsen male infertility. Heat stress can cause damage to the essential structure known as the blood-testis barrier (BTB). Photobiomodulation therapy (PBMT) has been employed in various studies to enhance sperm quality in individuals with genital inflammatory conditions in recent times. The current research sought to study how laser therapy affects spermatogenesis and the structure of the BTB in a mouse model of scrotal heat exposure. Methods: Thirty adult male NMRI mice, 8 weeks old, were divided into three groups: Control, Hyperthermia, and Hyperthermia+Laser 0.03 J/cm 2 . The animals in the hyperthermia group had their testicles exposed to water at 43 °C for 20 minutes five times every other day. Then, the testicles were exposed to laser radiation every other day for 35 days, lasting 3 minutes each time, with an energy density of 0.03 J/cm 2 . Animals were sacrificed, and sperm parameters, reactive oxygen species (ROS) and glutathione (GSH) levels, stereological parameters, and gene expression were assessed in the end. Results: The study showed that PBMT can significantly enhance sperm quality, quantity of spermatogenic cells, testicular volume, levels of ROS and GSH, and gene expression related to the blood-testis barrier. Conclusion: Currently, PBMT is a novel approach for addressing male infertility by preserving the integrity of the BTB in Sertoli cells, which in turn supports the growth and specialization of germ cells., Competing Interests: The authors declare that they have no competing interests., (Copyright © 2024 J Lasers Med Sci.)

Introduction: Diabetes is a highly prevalent disease worldwide. Despite routine treatments, there is no effective treatment approach for patients with diabetic foot ulcers (DFUs). A new approach to reduce complications and control DFU is low-level laser therapy (LLLT). In the present study, we evaluated the therapeutic effects of LLLT on the symptoms of DFU patients. Methods: Sixty diabetic patients with DFU were included in this randomized clinical trial and were randomly allocated into two groups of laser (n=30) and control (n=30) with signed written consent. The LLLT group underwent visible and infra-red laser therapy and conventional medical treatment, while the control group received only conventional medical treatment. The total laser irradiation sessions of the patients were 20 sessions, (three sessions a week) and each session lasted for 30 minutes over the entire surface of the wound. The power density per session for each laser was calculated to be 35.65 mW/cm 2 with an energy density of 64.17 J/cm 2 . Results: The mean area of ulcers in the LLLT group reduced significantly ( P <0.001) from 441.7±365.5 mm 2 before LLLT to 163.9±213.9 mm 2 from the baseline up to the last session of LLLT, indicating a 62.99% reduction in mean ulcer area. In the control group, the mean ulcer area did not change significantly. Wagner's classification of the patients in the LLLT group reduced to lower grades significantly ( P <0.01), while the classification moved towards higher grades in the control group ( P <0.08). Conclusion: In this study, we showed the effectiveness of LLLT in the reduction of the surface and depth of DFUs. The results documented that patients experienced significant improvements in the healing of their foot ulcers after laser therapy. It is recommended that the LLLT be considered as a non-invasive method for the treatment of DFU patients., Competing Interests: None., (Copyright © 2024 J Lasers Med Sci.)