The Experts below are selected from a list of 2010 Experts worldwide ranked by ideXlab platform
Minhsi Chiou - One of the best experts on this subject based on the ideXlab platform.
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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.
M Viliesid - One of the best experts on this subject based on the ideXlab platform.
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advice from the ccl on the use of unstabilized Lasers as standards of wavelength the helium neon laser at 633 nm
Metrologia, 2009Co-Authors: J A Stone, Jennifer E Decker, P Gill, P Juncar, Andrew Lewis, G D Rovera, M ViliesidAbstract:The Consultative Committee for Length (CCL) has recommended that red (633 nm) unstabilized helium–neon Lasers, operating on the 3s2 → 2p4 transition, should be included in the list of standard frequencies for realization of the metre. This paper discusses several topics relating to the recommendation: motivations for including an unstabilized laser in the list of standard frequencies, considerations in assigning a value and an uncertainty for the frequency and vacuum wavelength of the 633 nm transition, and problems associated with the possible presence of 640 nm radiation in the laser output. The fractional uncertainty assigned to the vacuum wavelength of the 633 nm transition is 1.5 × 10−6 (relative standard uncertainty). This uncertainty is sufficiently large to capture all sources of variability associated with construction or operating details of the laser and variations in isotopic mix that might be encountered in commercial laser tubes.
Hsinsu Yu - One of the best experts on this subject based on the ideXlab platform.
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low energy helium neon laser therapy induces repigmentation and improves the abnormalities of cutaneous microcirculation in segmental type vitiligo lesions
Kaohsiung Journal of Medical Sciences, 2008Co-Authors: Chiehshan Wu, Stephen Chusung Hu, Gwoshing Chen, Wenho Chuo, Hsinsu YuAbstract:Segmental vitiligo (SV) is a special form of vitiligo occurring in a dermatomal distribution, and an abnormality involving the sympathetic nerves supplying the affected dermatome is known to underlie this disorder. Previously, we have shown that SV is associated with an abnormal increase in cutaneous blood flow and adrenoceptor responses in the affected areas. Since SV is resistant to conventional forms of therapy, its management represents a challenge for dermatologists. Low energy Helium-Neon Lasers (He-Ne laser, wavelength 632.8nm) have been employed as a therapeutic instrument in many clinical situations, including vitiligo management and repair of nerve injury. The purpose of this study was to evaluate the effectiveness and safety of He-Ne Lasers in treating SV, and determine their effects on the repair of sympathetic nerve dysfunction. Forty patients with stable-stage SV on the head and/or neck were enrolled in this study. He-Ne laser irradiation was administered locally at 3.0J/cm 2 with point stimulation once or twice weekly. Cutaneous microcirculatory assessments in six SV patients were performed using a laser Doppler flowmeter. The sympathetic adrenoceptor response of cutaneous microcirculation was determined by measuring cutaneous blood flow before, during and after iontophoresis with sympathomimetic drugs (phenylephrine, clonidine and propranolol). All measurements of microcirculation obtained at SV lesions were simultaneously compared with contralateral normal skin, both before and after He-Ne laser treatment. After an average of 17 treatment sessions, initial repigmentation was noticed in the majority of patients. Marked repigmentation (> 50%) was observed in 60% of patients with successive treatments. Cutaneous blood flow was significantly higher at SV lesions compared with contralateral skin, but this was normalized after He-Ne laser treatment. In addition, the abnormal decrease in cutaneous blood flow in response to clonidine was improved by He-Ne laser therapy. Our study showed that He-Ne laser therapy is an effective treatment for SV by normalizing dysfunctions of cutaneous blood flow and adrenoceptor responses in SV patients. Thus, the beneficial effects of He-Ne laser therapy may be mediated in part by a reparative effect on sympathetic nerve dysfunction.
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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.
J A Stone - One of the best experts on this subject based on the ideXlab platform.
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advice from the ccl on the use of unstabilized Lasers as standards of wavelength the helium neon laser at 633 nm
Metrologia, 2009Co-Authors: J A Stone, Jennifer E Decker, P Gill, P Juncar, Andrew Lewis, G D Rovera, M ViliesidAbstract:The Consultative Committee for Length (CCL) has recommended that red (633 nm) unstabilized helium–neon Lasers, operating on the 3s2 → 2p4 transition, should be included in the list of standard frequencies for realization of the metre. This paper discusses several topics relating to the recommendation: motivations for including an unstabilized laser in the list of standard frequencies, considerations in assigning a value and an uncertainty for the frequency and vacuum wavelength of the 633 nm transition, and problems associated with the possible presence of 640 nm radiation in the laser output. The fractional uncertainty assigned to the vacuum wavelength of the 633 nm transition is 1.5 × 10−6 (relative standard uncertainty). This uncertainty is sufficiently large to capture all sources of variability associated with construction or operating details of the laser and variations in isotopic mix that might be encountered in commercial laser tubes.
Chiehshan Wu - One of the best experts on this subject based on the ideXlab platform.
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low energy helium neon laser therapy induces repigmentation and improves the abnormalities of cutaneous microcirculation in segmental type vitiligo lesions
Kaohsiung Journal of Medical Sciences, 2008Co-Authors: Chiehshan Wu, Stephen Chusung Hu, Gwoshing Chen, Wenho Chuo, Hsinsu YuAbstract:Segmental vitiligo (SV) is a special form of vitiligo occurring in a dermatomal distribution, and an abnormality involving the sympathetic nerves supplying the affected dermatome is known to underlie this disorder. Previously, we have shown that SV is associated with an abnormal increase in cutaneous blood flow and adrenoceptor responses in the affected areas. Since SV is resistant to conventional forms of therapy, its management represents a challenge for dermatologists. Low energy Helium-Neon Lasers (He-Ne laser, wavelength 632.8nm) have been employed as a therapeutic instrument in many clinical situations, including vitiligo management and repair of nerve injury. The purpose of this study was to evaluate the effectiveness and safety of He-Ne Lasers in treating SV, and determine their effects on the repair of sympathetic nerve dysfunction. Forty patients with stable-stage SV on the head and/or neck were enrolled in this study. He-Ne laser irradiation was administered locally at 3.0J/cm 2 with point stimulation once or twice weekly. Cutaneous microcirculatory assessments in six SV patients were performed using a laser Doppler flowmeter. The sympathetic adrenoceptor response of cutaneous microcirculation was determined by measuring cutaneous blood flow before, during and after iontophoresis with sympathomimetic drugs (phenylephrine, clonidine and propranolol). All measurements of microcirculation obtained at SV lesions were simultaneously compared with contralateral normal skin, both before and after He-Ne laser treatment. After an average of 17 treatment sessions, initial repigmentation was noticed in the majority of patients. Marked repigmentation (> 50%) was observed in 60% of patients with successive treatments. Cutaneous blood flow was significantly higher at SV lesions compared with contralateral skin, but this was normalized after He-Ne laser treatment. In addition, the abnormal decrease in cutaneous blood flow in response to clonidine was improved by He-Ne laser therapy. Our study showed that He-Ne laser therapy is an effective treatment for SV by normalizing dysfunctions of cutaneous blood flow and adrenoceptor responses in SV patients. Thus, the beneficial effects of He-Ne laser therapy may be mediated in part by a reparative effect on sympathetic nerve dysfunction.
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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.