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Mohammad Bayat - One of the best experts on this subject based on the ideXlab platform.
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effect of low level helium neon Laser therapy on histological and ultrastructural features of immobilized rabbit articular cartilage
Journal of Photochemistry and Photobiology B-biology, 2007Co-Authors: Mohammad Bayat, Enayatallah Ansari, Narges Gholami, Aghdas BayatAbstract:Abstract The present study investigates whether low-level helium–neon Laser therapy can increase histological parameters of immobilized articular cartilage in rabbits or not. Twenty five rabbits were divided into three groups: the experiment group, which received low-level helium–neon Laser therapy with 13 J/cm2 three times a week after immobilization of their right knees; the control group which did not receive Laser therapy after immobilization of their knees; and the normal group which received neither immobilization nor Laser therapy. Histological and electron microscopic examinations were performed at 4 and 7 weeks after immobilization. Depth of the chondrocyte filopodia in four-week immobilized experiment group, and depth of articular cartilage in seven-week immobilized experiment group were significantly higher than those of relevant control groups (exact Fisher test, p = 0.001; student’s t-test, p = 0.031, respectively). The surfaces of articular cartilages of the experiment group were relatively smooth, while those of the control group were unsmooth. It is therefore concluded that low-level helium–neon Laser therapy had significantly increased the depth of the chondrocyte filopodia in four-week immobilized femoral articular cartilage and the depth of articular cartilage in seven-week immobilized knee in comparison with control immobilized articular cartilage.
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effect of low level helium neon Laser therapy on the healing of third degree burns in rats
Journal of Photochemistry and Photobiology B-biology, 2006Co-Authors: Mohammad Bayat, Mohammad Mehdi Vasheghani, Naser RazaviAbstract:Abstract This paper presents the results of a study on the effects of low-level helium–neon Laser therapy (LL He–Ne LT) on the healing of burns. Seventy-eight adult male rats, having been subjected to third-degree burns, were randomly divided into four groups: two Laser treated groups ( n = 20, each), one control group ( n = 19) and one nitrofurazone treated group ( n = 19). In the two Laser treated groups, the burns were treated on a daily basis with LL He–Ne LT with an energy density of 1.2 and 2.4 J/cm 2 , respectively. The response to treatment was assessed histologically at 7, 16 and 30 days after burning, and microbiologically at day 15. Analysis of variance showed that the mean of blood vessel sections in the 1.2 J/cm 2 Laser group was significantly higher than those in the other groups and the mean of the depth of new epidermis in the 2.4 J/cm 2 Laser group on day 16 was significantly lower than in the nitrofurazone treated group ( P = 0.025, P = 0.047, respectively). When Staphylococcus aureus and Pseudomonas aeruginosa grew in more than 50% of samples obtained from control group, there were no S. aureus and P. aeruginosa in the samples of 2.4 J/cm 2 Laser group. It is concluded that LL He–Ne LT induced the destruction of S. aureus and P. aeruginosa in third-degree burns of rats, yet at the same time our histological findings showed that LL He–Ne LT caused a significant increase in the mean of blood vessel sections on day 7 after third degree burns and a decrease in the mean of the depth of new epidermis on day 16 after the same burns in rats.
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effect of low power helium neon Laser irradiation on 13 week immobilized articular cartilage of rabbits
Indian Journal of Experimental Biology, 2004Co-Authors: Mohammad Bayat, Anayatallah Ansari, Hossien HekmatAbstract:: Influence of low-power (632.8 nm, Helium-Neon, 13 J/cm2, three times a week) Laser on 13-week immobilized articular cartilage was examined with rabbits knee model. Number of chondrocytes and depth of articular cartilage of experimental group were significantly higher than those of sham irradiated group. Surface morphology of sham-irradiated group had rough prominences, fibrillation and lacunae but surface morphology of experimental group had more similarities to control group than to sham irradiated group. There were marked differences between ultrastructure features of control group and experimental group in comparison with sham irradiated group. Low-power Helium-Neon Laser irradiation on 13-week immobilized knee joints of rabbits neutrilized adverse effects of immobilization on articular cartilage.
Minhsi Chiou - One of the best experts on this subject based on the ideXlab platform.
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low energy helium neon Laser induces melanocyte proliferation via interaction with type iv collagen visible light as a therapeutic option for vitiligo
British Journal of Dermatology, 2009Co-Authors: C S Wu, Minhsi Chiou, T Y Chiang, H S YuAbstract:Summary Background The treatment of vitiligo remains a challenge for clinical dermatologists. We have previously shown that the helium–neon Laser (He–Ne Laser, 632·8 nm) is a therapeutic option for treatment of this depigmentary disorder. Objectives Addressing the intricate interactions between melanocytes, the most important cellular component in the repigmentation scheme of vitiligo, and their innate extracellular matrix collagen type IV, the current study aimed to elucidate the effects of the He–Ne Laser on melanocytes. Methods Cultured melanocytes were irradiated with the He–Ne Laser. Relevant biological parameters including cell attachment, locomotion and growth were evaluated. In addition, the potentially involved molecular pathways were also determined. Results Our results show that in addition to suppressing mobility but increasing attachment to type IV collagen, the He–Ne Laser stimulates melanocyte proliferation through enhanced α2β1 integrin expression. The expression of phosphorylated cyclic-AMP response element binding protein (CREB), an important regulator of melanocyte growth, was also upregulated by He–Ne Laser treatment. Using a specific mitochondrial uncoupling agent [carbonyl cyanide m-chlorophenyl-hydrazone (CCCP)], the proliferative effect of the He–Ne Laser on melanocytes was abolished and suppression of melanocyte growth was noted. Conclusions In summary, we have demonstrated that the He–Ne Laser imparts a growth stimulatory effect on functional melanocytes via mitochondria-related pathways and proposed that other minor pathways including DNA damage may also be inflicted by Laser treatment on irradiated cells. More importantly, we have completed the repigmentation scheme of vitiligo brought about by He–Ne Laser light in vitro and provided a solid theoretical basis regarding how the He–Ne Laser induces recovery of vitiligo in vivo.
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low energy helium neon Laser induces locomotion of the immature melanoblasts and promotes melanogenesis of the more differentiated melanoblasts recapitulation of vitiligo repigmentation in vitro
Journal of Investigative Dermatology, 2006Co-Authors: Chingshuang Wu, Minhsi Chiou, Peichen Hsieh, H S YuAbstract:Helium-Neon Laser (He-Ne Laser, 632.8nm) is a low-energy Laser that has therapeutic efficacy on various clinical conditions. Our previous study has demonstrated efficacy of He-Ne Laser on vitiligo, a disease characterized by skin depigmentation. To regain skin tone on vitiligo lesions, the process began by the migration of the immature melanoblasts (MBs) to the epidermis, which was followed by their functional development to produce melanin. In this study, we investigated the physiologic effects of He-Ne Laser irradiation on two MB cell lines: the immature NCCmelb4 and the more differentiated NCCmelan5. The intricate interactions between MBs with their innate extracelluar matrix, fibronectin, were also addressed. Our results showed that He-Ne Laser irradiation enhanced NCCmelb4 mobility via enhanced phosphorylated focal adhesion kinase expression and promoted melanogenesis in NCCmelan5. In addition, He-Ne Laser decreased the affinity between NCCmelb4 and fibronectin, whereas the attachment of NCCmelan5 to fibronectin increased. The α 5 β 1 integrin expression on NCCmelb4 cells was enhanced by He-Ne Laser. In conclusion, we have demonstrated that He-Ne Laser induced different physiologic changes on MBs at different maturation stages and recapitulated the early events during vitiligo repigmentation process brought upon by He-Ne Laser in vitro .
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helium neon Laser irradiation stimulates migration and proliferation in melanocytes and induces repigmentation in segmental type vitiligo
Journal of Investigative Dermatology, 2003Co-Authors: Hsinsu Yu, Chiehshan Wu, Chiali Yu, Minhsi ChiouAbstract:Low-energy helium–neon Lasers (632.8 nm) have been employed in a variety of clinical treatments including vitiligo management. Light-mediated reaction to low-energy Laser irradiation is referred to as biostimulation rather than a thermal effect. This study sought to determine the theoretical basis and clinical evidence for the effectiveness of helium–neon Lasers in treating vitiligo. Cultured keratinocytes and fibroblasts were irradiated with 0.5–1.5 J per cm2 Helium-Neon Laser radiation. The effects of the helium–neon Laser on melanocyte growth and proliferation were investigated. The results of this in vitro study revealed a significant increase in basic fibroblast growth factor release from both keratinocytes and fibroblasts and a significant increase in nerve growth factor release from keratinocytes. Medium from helium–neon Laser irradiated keratinocytes stimulated [3H]thymidine uptake and proliferation of cultured melanocytes. Furthermore, melanocyte migration was enhanced either directly by helium–neon Laser irradiation or indirectly by the medium derived from helium–neon Laser treated keratinocytes. Thirty patients with segmental-type vitiligo on the head and/or neck were enrolled in this study. Helium-Neon Laser light was administered locally at 3.0 J per cm2 with point stimulation once or twice weekly. The percentage of repigmented area was used for clinical evaluation of effectiveness. After an average of 16 treatment sessions, initial repigmentation was noticed. Marked repigmentation (>50%) was observed in 60% of patients with successive treatments. Basic fibroblast growth factor is a putative melanocyte growth factor, whereas nerve growth factor is a paracrine factor for melanocyte survival in the skin. Both nerve growth factor and basic fibroblast growth factor stimulate melanocyte migration. It is reasonable to propose that Helium-Neon Laser irradiation clearly stimulates melanocyte migration and proliferation and mitogen release for melanocyte growth and may also rescue damaged melanocytes, therefore providing a microenvironment for inducing repigmentation in vitiligo.
Hsinsu Yu - One of the best experts on this subject based on the ideXlab platform.
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helium neon Laser irradiation stimulates cell proliferation through photostimulatory effects in mitochondria
Journal of Investigative Dermatology, 2007Co-Authors: Wanping Hu, Chiali Yu, Jehjeng Wang, Gowshing Chen, Hsinsu YuAbstract:Previous reports have shown that cellular functions could be influenced by visual light (400–700nm). Recent evidence indicates that cellular proliferation could be triggered by the interaction of a helium–neon Laser (He-Ne Laser, 632.8nm) with the mitochondrial photoacceptor-cytochrome c oxidase. Our previous studies demonstrated that He-Ne irradiation induced an increase in cell proliferation, but not migration, in the melanoma cell line A2058 cell. The aim of this study was to investigate the underlying mechanisms involved in photostimulatory effects induced by an He-Ne Laser. Using the A2058 cell as a model for cell proliferation, the photobiologic effects induced by an He-Ne Laser were studied. He-Ne irradiation immediately induced an increase in mitochondrial membrane potential (ΔΨ mt ), ATP, and cAMP via enhanced cytochrome c oxidase activity and promoted phosphorylation of Jun N-terminal kinase (JNK)/activator protein-1 (AP-1) expressions. He-Ne irradiation-induced A2058 cell proliferation was significantly abrogated by the addition of ΔΨ mt and JNK inhibitors. Moreover, treatment with an He-Ne Laser resulted in delayed effects on IL-8 and transforming growth factor- β 1 release from A2058 cells. These results suggest that He-Ne irradiation elicits photostimulatory effects in mitochondria processes, which involve JNK/AP-1 activation and enhanced growth factor release, and ultimately lead to A2058 cell proliferation.
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helium neon Laser irradiation stimulates migration and proliferation in melanocytes and induces repigmentation in segmental type vitiligo
Journal of Investigative Dermatology, 2003Co-Authors: Hsinsu Yu, Chiehshan Wu, Chiali Yu, Minhsi ChiouAbstract:Low-energy helium–neon Lasers (632.8 nm) have been employed in a variety of clinical treatments including vitiligo management. Light-mediated reaction to low-energy Laser irradiation is referred to as biostimulation rather than a thermal effect. This study sought to determine the theoretical basis and clinical evidence for the effectiveness of helium–neon Lasers in treating vitiligo. Cultured keratinocytes and fibroblasts were irradiated with 0.5–1.5 J per cm2 Helium-Neon Laser radiation. The effects of the helium–neon Laser on melanocyte growth and proliferation were investigated. The results of this in vitro study revealed a significant increase in basic fibroblast growth factor release from both keratinocytes and fibroblasts and a significant increase in nerve growth factor release from keratinocytes. Medium from helium–neon Laser irradiated keratinocytes stimulated [3H]thymidine uptake and proliferation of cultured melanocytes. Furthermore, melanocyte migration was enhanced either directly by helium–neon Laser irradiation or indirectly by the medium derived from helium–neon Laser treated keratinocytes. Thirty patients with segmental-type vitiligo on the head and/or neck were enrolled in this study. Helium-Neon Laser light was administered locally at 3.0 J per cm2 with point stimulation once or twice weekly. The percentage of repigmented area was used for clinical evaluation of effectiveness. After an average of 16 treatment sessions, initial repigmentation was noticed. Marked repigmentation (>50%) was observed in 60% of patients with successive treatments. Basic fibroblast growth factor is a putative melanocyte growth factor, whereas nerve growth factor is a paracrine factor for melanocyte survival in the skin. Both nerve growth factor and basic fibroblast growth factor stimulate melanocyte migration. It is reasonable to propose that Helium-Neon Laser irradiation clearly stimulates melanocyte migration and proliferation and mitogen release for melanocyte growth and may also rescue damaged melanocytes, therefore providing a microenvironment for inducing repigmentation in vitiligo.
H S Yu - One of the best experts on this subject based on the ideXlab platform.
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low energy helium neon Laser induces melanocyte proliferation via interaction with type iv collagen visible light as a therapeutic option for vitiligo
British Journal of Dermatology, 2009Co-Authors: C S Wu, Minhsi Chiou, T Y Chiang, H S YuAbstract:Summary Background The treatment of vitiligo remains a challenge for clinical dermatologists. We have previously shown that the helium–neon Laser (He–Ne Laser, 632·8 nm) is a therapeutic option for treatment of this depigmentary disorder. Objectives Addressing the intricate interactions between melanocytes, the most important cellular component in the repigmentation scheme of vitiligo, and their innate extracellular matrix collagen type IV, the current study aimed to elucidate the effects of the He–Ne Laser on melanocytes. Methods Cultured melanocytes were irradiated with the He–Ne Laser. Relevant biological parameters including cell attachment, locomotion and growth were evaluated. In addition, the potentially involved molecular pathways were also determined. Results Our results show that in addition to suppressing mobility but increasing attachment to type IV collagen, the He–Ne Laser stimulates melanocyte proliferation through enhanced α2β1 integrin expression. The expression of phosphorylated cyclic-AMP response element binding protein (CREB), an important regulator of melanocyte growth, was also upregulated by He–Ne Laser treatment. Using a specific mitochondrial uncoupling agent [carbonyl cyanide m-chlorophenyl-hydrazone (CCCP)], the proliferative effect of the He–Ne Laser on melanocytes was abolished and suppression of melanocyte growth was noted. Conclusions In summary, we have demonstrated that the He–Ne Laser imparts a growth stimulatory effect on functional melanocytes via mitochondria-related pathways and proposed that other minor pathways including DNA damage may also be inflicted by Laser treatment on irradiated cells. More importantly, we have completed the repigmentation scheme of vitiligo brought about by He–Ne Laser light in vitro and provided a solid theoretical basis regarding how the He–Ne Laser induces recovery of vitiligo in vivo.
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low energy helium neon Laser induces locomotion of the immature melanoblasts and promotes melanogenesis of the more differentiated melanoblasts recapitulation of vitiligo repigmentation in vitro
Journal of Investigative Dermatology, 2006Co-Authors: Chingshuang Wu, Minhsi Chiou, Peichen Hsieh, H S YuAbstract:Helium-Neon Laser (He-Ne Laser, 632.8nm) is a low-energy Laser that has therapeutic efficacy on various clinical conditions. Our previous study has demonstrated efficacy of He-Ne Laser on vitiligo, a disease characterized by skin depigmentation. To regain skin tone on vitiligo lesions, the process began by the migration of the immature melanoblasts (MBs) to the epidermis, which was followed by their functional development to produce melanin. In this study, we investigated the physiologic effects of He-Ne Laser irradiation on two MB cell lines: the immature NCCmelb4 and the more differentiated NCCmelan5. The intricate interactions between MBs with their innate extracelluar matrix, fibronectin, were also addressed. Our results showed that He-Ne Laser irradiation enhanced NCCmelb4 mobility via enhanced phosphorylated focal adhesion kinase expression and promoted melanogenesis in NCCmelan5. In addition, He-Ne Laser decreased the affinity between NCCmelb4 and fibronectin, whereas the attachment of NCCmelan5 to fibronectin increased. The α 5 β 1 integrin expression on NCCmelb4 cells was enhanced by He-Ne Laser. In conclusion, we have demonstrated that He-Ne Laser induced different physiologic changes on MBs at different maturation stages and recapitulated the early events during vitiligo repigmentation process brought upon by He-Ne Laser in vitro .
Aghdas Bayat - One of the best experts on this subject based on the ideXlab platform.
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effect of low level helium neon Laser therapy on histological and ultrastructural features of immobilized rabbit articular cartilage
Journal of Photochemistry and Photobiology B-biology, 2007Co-Authors: Mohammad Bayat, Enayatallah Ansari, Narges Gholami, Aghdas BayatAbstract:Abstract The present study investigates whether low-level helium–neon Laser therapy can increase histological parameters of immobilized articular cartilage in rabbits or not. Twenty five rabbits were divided into three groups: the experiment group, which received low-level helium–neon Laser therapy with 13 J/cm2 three times a week after immobilization of their right knees; the control group which did not receive Laser therapy after immobilization of their knees; and the normal group which received neither immobilization nor Laser therapy. Histological and electron microscopic examinations were performed at 4 and 7 weeks after immobilization. Depth of the chondrocyte filopodia in four-week immobilized experiment group, and depth of articular cartilage in seven-week immobilized experiment group were significantly higher than those of relevant control groups (exact Fisher test, p = 0.001; student’s t-test, p = 0.031, respectively). The surfaces of articular cartilages of the experiment group were relatively smooth, while those of the control group were unsmooth. It is therefore concluded that low-level helium–neon Laser therapy had significantly increased the depth of the chondrocyte filopodia in four-week immobilized femoral articular cartilage and the depth of articular cartilage in seven-week immobilized knee in comparison with control immobilized articular cartilage.