Effects of transcranial photobiomodulation and methylene blue on biochemical and behavioral profiles in mice stress model

Open Access via Springer Compact Agreement. Acknowledgements This article was derived from the MSc dissertation of Mr. Reza Meynaghizadeh-Zargar. Funding The present study was supported by Neurosciences Research Center of Tabriz University of Medical Sciences (grant number, 58471).Peer reviewedPublisher PD

Low-Level Laser Irradiation Modulated Viability of Normal and Tumor Human Lymphocytes In Vitro

Introduction: Laser radiation is a promising strategy against various malignancies. Recent studies have shown that the application of low-power laser therapy (LPLT) at different doses and exposure times could modulate the growth dynamic of tumor cells. Based on the type of laser, LPLT could potentially trigger cell proliferation, differentiation, and apoptosis in different cell lines.Methods: In this study, MTT assay was used to monitor the effect of low and high laser intensities on the viability of normal and cancer lymphocytes. The protein levels of Ki-67 (a proliferation marker) and Caspase-3 (an apoptosis factor) were measured in human peripheral mononuclear cells (PBMCs) and the B-lymphoblastic cell line (Nalm-6) using flow cytometry after being-exposed to 630-nm LPLT at low (2, 4, 6, and 10 J/cm2) and high (15, 30, 60, and 120 J/cm2) energy densities in a continuous mode for 48 and 72 hours.Results: By using higher energy densities, 60 and 120 J/cm2, a significant decrease was shown in the viability of Nalm-6 cells, which reached 6.6 and 10.1% after 48 hours compared to the control cells (P < 0.05). Notably, Cell exposure to doses 30, 60, and 120 J/cm2 yielded 7.5, 12.9, and 21.6 cell viability reduction after 72 hours. The collected data showed that the high-intensity parameters of LPLT (15 to 120 J/cm2) promoted significant apoptotic changes in the exposed cells coincided with the activation of Caspase-3 compared to the none-treated control cells (P < 0.05). The data further showed the stimulation of the Ki-67 factor both in primary PBMCs and the lymphoblastic cell line treated with LPLT at energy densities of 4 and 6 J/cm2 (P < 0.05), indicating enhanced cell proliferation. Similar to Nalm-6 cells, primary PBMCs showed apoptosis after 48 hours of being exposed to doses 60, and 120 J/cm2, indicated by increased Caspase-3 levels (P < 0.05). As expected, the Nalm-6 cells were resistant to cytotoxic effects of laser irradiation in the first 48 hours (P > 0.05) compared to normal PBMCs. The exposure of Nalm-6 cells to low-intensity laser intensities increased a proliferation rate compared to the PBMCs treated with the same doses.Conclusion: We showed the potency of LPLT in the induction of apoptosis and proliferation in human primary PBMCs and Nalm-6 cells in a dose and time-dependent manner after 72 hours.

Detection of retinal capillary nonperfusion in fundus fluorescein angiogram of diabetic retinopathy

Introduction: Retinal capillary nonperfusion (CNP) is one of the retinal vascular diseases in diabetic retinopathy (DR) patients. As there is no comprehensive detection technique to recognize CNP areas, we proposed a different method for computing detection of ischemic retina, non-perfused (NP) regions, in fundus fluorescein angiogram (FFA) images. Methods: Whilst major vessels appear as ridges, non-perfused areas are usually observed as ponds that are surrounded by healthy capillaries in FFA images. A new technique using homomorphic filtering to correct light illumination and detect the ponds surrounded in healthy capillaries on FFA images was designed and applied on DR fundus images. These images were acquired from the diabetic patients who had referred to the Nikookari hospital and were diagnosed for diabetic retinopathy during one year. Our strategy was screening the whole image with a fixed window size, which is small enough to enclose areas with identified topographic characteristics. To discard false nominees, we also performed a thresholding operation on the screen and marked images. To validate its performance we applied our detection algorithm on 41 FFA diabetic retinopathy fundus images in which the CNP areas were manually delineated by three clinical experts. Results: Lesions were found as smooth regions with very high uniformity, low entropy, and small intensity variations in FFA images. The results of automated detection method were compared with manually marked CNP areas so achieved sensitivity of 81%, specificity of 78%, and accuracy of 91%.The result was present as a Receiver operating character (ROC) curve, which has an area under the curve (AUC) of 0.796 with 95% confidence intervals. Conclusion: This technique introduced a new automated detection algorithm to recognize non-perfusion lesions on FFA. This has potential to assist detecting and managing of ischemic retina and may be incorporated into automated grading diabetic retinopathy structures

Discriminant analysis between myocardial infarction patients and healthy subjects using wavelet transformed signal averaged electrocardiogram and probabilistic neural network

There are a variety of electrocardiogram based methods to detect myocardial infarction (MI) patients. This study used the signal averaged electrocardiogram (SAECG) and its wavelet coefficient as an index to detect MI. Orthogonal leads signals from 50 acute myocardial infarction (AMI) and 50 healthy subjects were selected from the national metrology institute of Germany (PTB diagnostic database). They were filtered and discrete wavelet transformed was exerted on them. Four conventional features and two new features introduced in this study were extracted from SAECG and its wavelet decompositions. Finally for data classification, probabilistic neural network were used. This method was able to detect and discriminate AMI patients from healthy subjects using the probabilistic neural network, which shows 93.0% sensitivity at 86.0% specificity with 89.5% accuracy. This technique and the new extracted features showed good promise in the identification of MI patients. However, the sensitivity and specificity is comparable with other findings and has high accuracy although we extracted only 6 features

A comparative study on preprocessing techniques in diabetic retinopathy retinal images: Illumination correction and contrast enhancement

To investigate the effect of preprocessing techniques including contrast enhancement and illumination correction on retinal image quality, a comparative study was carried out. We studied and implemented a few illumination correction and contrast enhancement techniques on color retinal images to find out the best technique for optimum image enhancement. To compare and choose the best illumination correction technique we analyzed the corrected red and green components of color retinal images statistically and visually. The two contrast enhancement techniques were analyzed using a vessel segmentation algorithm by calculating the sensitivity and specificity. The statistical evaluation of the illumination correction techniques were carried out by calculating the coefficients of variation. The dividing method using the median filter to estimate background illumination showed the lowest coefficients of variation in the red component. The quotient and homomorphic filtering methods after the dividing method presented good results based on their low coefficients of variation . The contrast limited adaptive histogram equalization contrast limited adaptive histogram equalization increased the sensitivity of the vessel segmentation algorithm up to 5% in the same amount of accuracy. The contrast limited adaptive histogram equalization technique has a higher sensitivity than the polynomial transformation operator as a contrast enhancement technique for vessel segmentation. Three techniques including the dividing method using the median filter to estimate background, quotient based and homomorphic filtering were found as the effective illumination correction techniques based on a statistical evaluation. Applying the local contrast enhancement technique, such as contrast limited adaptive histogram equalization, for fundus images presented good potentials in enhancing the vasculature segmentation

Low-level laser irradiation at a high power intensity increased human endothelial cell exosome secretion via Wnt signaling (vol, pg, )

Talebi, Mehdi/0000-0002-3633-2280; Bagheri, Hesam Saghaei/0000-0002-1706-214X; Rezabakhsh, Aysa/0000-0003-3942-7848; Avci, Cigir Biray/0000-0001-8251-4520; Rahbarghazi, Reza/0000-0003-3864-9166; Rezaie, Jafar/0000-0001-8175-3730WOS: 000499601800002PubMed: 31782021[No abstract available

Low-level laser irradiation at a high power intensity increased human endothelial cell exosome secretion via Wnt signaling

WOS: 000435589100024PubMed ID: 29603107The distinct role of low-level laser irradiation (LLLI) on endothelial exosome biogenesis remains unclear. We hypothesize that laser irradiation of high dose in human endothelial cells (ECs) contributes to the modulation of exosome biogenesis via Wnt signaling pathway. When human ECs were treated with LLLI at a power density of 80 J/cm(2), the survival rate reduced. The potential of irradiated cells to release exosomes was increased significantly by expressing genes CD63, Alix, Rab27a, and b. This occurrence coincided with an enhanced acetylcholine esterase activity, pseudopodia formation, and reduced zeta potential value 24 h post-irradiation. Western blotting showed the induction of LC3 and reduced level of P62, confirming autophagy response. Flow cytometry and electron microscopy analyses revealed the health status of the mitochondrial function indicated by normal Delta I activity without any changes in the transcription level of PINK1 and Optineurin. When cells exposed to high power laser irradiation, p-Akt/Akt ratio and in vitro tubulogenesis capacity were blunted. PCR array and bioinformatics analyses showed the induction of transcription factors promoting Wnt signaling pathways and GTPase activity. Thus, LLLI at high power intensity increased exosome biogenesis by the induction of autophagy and Wnt signaling. LLLI at high power intensity increases exosome biogenesis by engaging the transcription factors related to Wnt signaling and autophagy stimulate.Tabriz University of Medical Sciences, Tabriz, IranThis study was supported by a grant from Tabriz University of Medical Sciences, Tabriz, Iran